WorldWideScience

Sample records for abdominal clutter reduction

  1. Mine detection using SF-GPR: A signal processing approach for resolution enhancement and clutter reduction

    DEFF Research Database (Denmark)

    Karlsen, Brian; Jakobsen, Kaj Bjarne; Larsen, Jan;

    2001-01-01

    Proper clutter reduction is essential for Ground Penetrating Radar data since low signal-to-clutter ratio prevent correct detection of mine objects. A signal processing approach for resolution enhancement and clutter reduction used on Stepped-Frequency Ground Penetrating Radar (SF-GPR) data is pr...

  2. Artificial Neural Network-Based Clutter Reduction Systems for Ship Size Estimation in Maritime Radars

    Directory of Open Access Journals (Sweden)

    Vicen-Bueno R

    2010-01-01

    Full Text Available The existence of clutter in maritime radars deteriorates the estimation of some physical parameters of the objects detected over the sea surface. For that reason, maritime radars should incorporate efficient clutter reduction techniques. Due to the intrinsic nonlinear dynamic of sea clutter, nonlinear signal processing is needed, what can be achieved by artificial neural networks (ANNs. In this paper, an estimation of the ship size using an ANN-based clutter reduction system followed by a fixed threshold is proposed. High clutter reduction rates are achieved using 1-dimensional (horizontal or vertical integration modes, although inaccurate ship width estimations are achieved. These estimations are improved using a 2-dimensional (rhombus integration mode. The proposed system is compared with a CA-CFAR system, denoting a great performance improvement and a great robustness against changes in sea clutter conditions and ship parameters, independently of the direction of movement of the ocean waves and ships.

  3. A bat inspired technique for clutter reduction in radar sounder systems

    Science.gov (United States)

    Carrer, L.; Bruzzone, L.

    2016-10-01

    Radar Sounders are valuable instruments for subsurface investigation. They are widely employed for the study of planetary bodies around the solar system. Due to their wide antenna beam pattern, off-nadir surface reflections (i.e. clutter) of the transmitted signal can compete with echoes coming from the subsurface thus masking them. Different strategies have been adopted for clutter mitigation. However, none of them proved to be the final solution for this specific problem. Bats are very well known for their ability in discriminating between a prey and unwanted clutter (e.g. foliage) by effectively employing their sonar. According to recent studies, big brown bats can discriminate clutter by transmitting two different carrier frequencies. Most interestingly, there are many striking analogies between the characteristics of the bat sonar and the one of a radar sounder. Among the most important ones, they share the same nadir acquisition geometry and transmitted signal type (i.e. linear frequency modulation). In this paper, we explore the feasibility of exploiting frequency diversity for the purpose of clutter discrimination in radar sounding by mimicking unique bats signal processing strategies. Accordingly, we propose a frequency diversity clutter reduction method based on specific mathematical conditions that, if verified, allow the disambiguation between the clutter and the subsurface signal to be performed. These analytic conditions depend on factors such as difference in central carrier frequencies, surface roughness and subsurface material properties. The method performance has been evaluated by different simulations of meaningful acquisition scenarios which confirm its clutter reduction effectiveness.

  4. New adaptive clutter rejection based on spectral analysis for ultrasound color Doppler imaging: phantom and in vivo abdominal study.

    Science.gov (United States)

    Geunyong Park; Sunmi Yeo; Jae Jin Lee; Changhan Yoon; Hyun-Woo Koh; Hyungjoon Lim; Youngtae Kim; Hwan Shim; Yangmo Yoo

    2014-01-01

    Effective rejection of time-varying clutter originating from slowly moving vessels and surrounding tissues is important for depicting hemodynamics in ultrasound color Doppler imaging (CDI). In this paper, a new adaptive clutter rejection method based on spectral analysis (ACR-SA) is presented for suppressing nonstationary clutter. In ACR-SA, tissue and flow characteristics are analyzed by singular value decomposition and tissue acceleration of backscattered Doppler signals to determine an appropriate clutter filter from a set of clutter filters. To evaluate the ACR-SA method, 20 frames of complex baseband data were acquired by a commercial ultrasound system equipped with a research package (Accuvix V10, Samsung Medison, Seoul, Korea) using a 3.5-MHz convex array probe by introducing tissue movements to the flow phantom (Gammex 1425 A LE, Gammex, Middleton, WI, USA). In addition, 20 frames of in vivo abdominal data from five volunteers were captured. From the phantom experiment, the ACR-SA method provided 2.43 dB (p SCR) compared to static (STA) and down-mixing (ACR-DM) methods. Similarly, it showed smaller values in fractional residual clutter area (FRCA) compared to the STA and ACR-DM methods (i.e., 2.3% versus 5.4% and 3.7%, respectively, ). The consistent improvements in SCR from the proposed ACR-SA method were obtained with the in vivo abdominal data (i.e., 4.97 dB and 3.39 dB over STA and ACR-DM, respectively). The ACR-SA method showed less than 1% FRCA values for all in vivo abdominal data. These results indicate that the proposed ACR-SA method can improve image quality in CDI by providing enhanced rejection of nonstationary clutter.

  5. Reduction of background clutter in structured lighting systems

    Science.gov (United States)

    Carlson, Jeffrey J.; Giles, Michael K.; Padilla, Denise D.; Davidson, Jr., Patrick A.; Novick, David K.; Wilson, Christopher W.

    2010-06-22

    Methods for segmenting the reflected light of an illumination source having a characteristic wavelength from background illumination (i.e. clutter) in structured lighting systems can comprise pulsing the light source used to illuminate a scene, pulsing the light source synchronously with the opening of a shutter in an imaging device, estimating the contribution of background clutter by interpolation of images of the scene collected at multiple spectral bands not including the characteristic wavelength and subtracting the estimated background contribution from an image of the scene comprising the wavelength of the light source and, placing a polarizing filter between the imaging device and the scene, where the illumination source can be polarized in the same orientation as the polarizing filter. Apparatus for segmenting the light of an illumination source from background illumination can comprise an illuminator, an image receiver for receiving images of multiple spectral bands, a processor for calculations and interpolations, and a polarizing filter.

  6. A model and regularization scheme for ultrasonic beamforming clutter reduction.

    Science.gov (United States)

    Byram, Brett; Dei, Kazuyuki; Tierney, Jaime; Dumont, Douglas

    2015-11-01

    Acoustic clutter produced by off-axis and multipath scattering is known to cause image degradation, and in some cases these sources may be the prime determinants of in vivo image quality. We have previously shown some success addressing these sources of image degradation by modeling the aperture domain signal from different sources of clutter, and then decomposing aperture domain data using the modeled sources. Our previous model had some shortcomings including model mismatch and failure to recover B-Mode speckle statistics. These shortcomings are addressed here by developing a better model and by using a general regularization approach appropriate for the model and data. We present results with L1 (lasso), L2 (ridge), and L1/L2 combined (elastic-net) regularization methods. We call our new method aperture domain model image reconstruction (ADMIRE). Our results demonstrate that ADMIRE with L1 regularization, or weighted toward L1 in the case of elastic-net regularization, have improved image quality. L1 by itself works well, but additional improvements are seen with elastic-net regularization over the pure L1 constraint. On in vivo example cases, L1 regularization showed mean contrast improvements of 4.6 and 6.8 dB on fundamental and harmonic images, respectively. Elastic net regularization (α = 0.9) showed mean contrast improvements of 17.8 dB on fundamental images and 11.8 dB on harmonic images. We also demonstrate that in uncluttered Field II simulations the decluttering algorithm produces the same contrast, contrast-tonoise ratio, and speckle SNR as normal B-mode imaging, demonstrating that ADMIRE preserves typical image features.

  7. Ground Clutter Reduction from GPR Data for Identification of Shallowly Buried Landmines

    Science.gov (United States)

    Nishimoto, Masahiko; Jandieri, Vakhtang

    A method for reducing ground clutter contribution from ground penetrating radar (GPR) data is proposed for discrimination of landmines located in shallow depth. The algorithm of this method is based on the Matching Pursuit (MP) that is a technique for non-orthogonal signal decomposition using dictionary of functions. As the dictionary of function, a wave-based dictionary constructed by taking account of scattering mechanisms of electromagnetic (EM) wave by rough surfaces is employed. Through numerical simulations, performance of ground clutter reduction is evaluated. The results show that the proposed method has good performance and is effective for GPR data preprocessing for discrimination of shallowly buried landmines.

  8. Algorithm for image registration and clutter and jitter noise reduction

    Energy Technology Data Exchange (ETDEWEB)

    Brower, K.L.

    1997-02-01

    This paper presents an analytical, computational method whereby two-dimensional images of an optical source represented in terms of a set of detector array signals can be registered with respect to a reference set of detector array signals. The detector image is recovered from the detector array signals and represented over a local region by a fourth order, two-dimensional taylor series. This local detector image can then be registered by a general linear transformation with respect to a reference detector image. The detector signal in the reference frame is reconstructed by integrating this detector image over the respective reference pixel. For cases in which the general linear transformation is uncertain by up to plus-or-minus two pixels, the general linear transformation can be determined by least squares fitting the detector image to the reference detector image. This registration process reduces clutter and jitter noise to a level comparable to the electronic noise level of the detector system. Test results with and without electronic noise using an analytical test function are presented.

  9. Comparison of PCA and ICA based clutter reduction in GPR systems for anti-personal landmine detection

    DEFF Research Database (Denmark)

    Karlsen, Brian; Larsen, Jan; Sørensen, Helge Bjarup Dissing;

    2001-01-01

    This paper presents statistical signal processing approaches for clutter reduction in stepped-frequency ground penetrating radar (SF-GPR) data. In particular, we suggest clutter/signal separation techniques based on principal and independent component analysis (PCA/ICA). The approaches are succes...

  10. Reduction of Surface Clutter by a Polarimetric FM-CW Radar in Underground Target Detection

    OpenAIRE

    Moriyama, Toshifumi; Yamaguchi, Yoshio; Sengoku, Masakazu; Yamada, Hiroyoshi

    1995-01-01

    This paper presents an experimental result of polarimetric detection of objects buried in a sandy ground by a synthetic aperture FM-CW radar. Emphasis is placed on the reduction of surface clutter by the polarimetric radar, which takes account of full polarimetric scattering characteristics. First, the principle of full polarimetric imaging methodology is out-lined based on the characteristic polarization states for a specific target together with a polarimetric enhancement factor which discr...

  11. Comparison of PCA and ICA based clutter reduction in GPR systems for anti-personal landmine detection

    OpenAIRE

    Karlsen, Brian; Larsen, Jan; Sørensen, Helge Bjarup Dissing; Jakobsen, Kaj Bjarne

    2001-01-01

    This paper presents statistical signal processing approaches for clutter reduction in stepped-frequency ground penetrating radar (SF-GPR) data. In particular, we suggest clutter/signal separation techniques based on principal and independent component analysis (PCA/ICA). The approaches are successfully evaluated and compared on a real SF-GPR time-series. Field-test data are acquired using a monostatic S-band rectangular waveguide antenna.

  12. Photoacoustic clutter reduction by inversion of a linear scatter model using plane wave ultrasound measurements.

    Science.gov (United States)

    Schwab, Hans-Martin; Beckmann, Martin F; Schmitz, Georg

    2016-04-01

    Photoacoustic imaging aims to visualize light absorption properties of biological tissue by receiving a sound wave that is generated inside the observed object as a result of the photoacoustic effect. In clinical applications, the strong light absorption in human skin is a major problem. When high amplitude photoacoustic waves that originate from skin absorption propagate into the tissue, they are reflected back by acoustical scatterers and the reflections contribute to the received signal. The artifacts associated with these reflected waves are referred to as clutter or skin echo and limit the applicability of photoacoustic imaging for medical applications severely. This study seeks to exploit the acoustic tissue information gained by plane wave ultrasound measurements with a linear array in order to correct for reflections in the photoacoustic image. By deriving a theory for clutter waves in k-space and a matching inversion approach, photoacoustic measurements compensated for clutter are shown to be recovered.

  13. An improved MTI filter for ground clutter reduction in UAV classification

    Science.gov (United States)

    Wan, Fangyuan; Liu, Qinglai; Wang, Chen; Guo, Xin; Lin, Zhiping

    2017-06-01

    In recent years, Unmanned Aerial Vehicles (UAVs) have increasingly been used in many civil applications. However, they also pose a significant threat in restricted zones. Radar can be used to detect and discriminate UAVs. Due to the low flying altitude of the UAVs, it is found that the radar signals also include some unwanted echoes, reflected by building, ground, trees and grasses etc. Consequently, it has not been possible to get the clean UAVs characteristics for further classification. In this paper, the MTI filter is applied to cancel the ground clutter and based this, an improved MTI filter is further proposed. Compared with the traditional MTI filter, the improved one significantly enhances ground clutter rejection capability while maintaining most of the target power. As the result, the cleaner UAVs classification characteristics can be obtained. The effectiveness of the proposed method has been verified by an experimental CW radar dataset, collected from a helicopter UAV.

  14. Negative pressure device for intra-abdominal pressure reduction

    Energy Technology Data Exchange (ETDEWEB)

    David, M; Geido, D; Pracca, F; Sanchez, G; Simini, F; Zoppolo, C [Nucleo de Ingenierfa Biomedica, Universidad de la Republica O. del Uruguay, Hospital de ClInicas, Av. Italia S/N, 11600, Montevideo (Uruguay)

    2007-11-15

    A device that generates negative extra-abdominal pressure (ABDOPRE) for treatment of patients with high intra-abdominal pressure was developed. It includes pressure sensors for transducing intra-abdominal pressure through an intra-vesical catheter and negative pressure in the vacuum bell which is placed over the abdomen. By means of a control system, a pattern for reducing IAP is set, according to a clinical protocol. The external negative pressure is generated using a vacuum pump connected to the bell. The system registers the values of interest for the medical history. The system is being tested over ICU patients, registering a satisfactory IAP reduction.

  15. Robust frequency diversity based algorithm for clutter noise reduction of ultrasonic signals using multiple sub-spectrum phase coherence

    Energy Technology Data Exchange (ETDEWEB)

    Gongzhang, R.; Xiao, B.; Lardner, T.; Gachagan, A. [Centre for Ultrasonic Engineering, University of Strathclyde, Glasgow, G1 1XW (United Kingdom); Li, M. [School of Engineering, University of Glasgow, Glasgow, G12 8QQ (United Kingdom)

    2014-02-18

    This paper presents a robust frequency diversity based algorithm for clutter reduction in ultrasonic A-scan waveforms. The performance of conventional spectral-temporal techniques like Split Spectrum Processing (SSP) is highly dependent on the parameter selection, especially when the signal to noise ratio (SNR) is low. Although spatial beamforming offers noise reduction with less sensitivity to parameter variation, phased array techniques are not always available. The proposed algorithm first selects an ascending series of frequency bands. A signal is reconstructed for each selected band in which a defect is present when all frequency components are in uniform sign. Combining all reconstructed signals through averaging gives a probability profile of potential defect position. To facilitate data collection and validate the proposed algorithm, Full Matrix Capture is applied on the austenitic steel and high nickel alloy (HNA) samples with 5MHz transducer arrays. When processing A-scan signals with unrefined parameters, the proposed algorithm enhances SNR by 20dB for both samples and consequently, defects are more visible in B-scan images created from the large amount of A-scan traces. Importantly, the proposed algorithm is considered robust, while SSP is shown to fail on the austenitic steel data and achieves less SNR enhancement on the HNA data.

  16. Clutter noise reduction for phased array imaging using frequency-spatial polarity coherence

    Science.gov (United States)

    Gongzhang, Rui; Gachagan, Anthony; Xiao, Bo

    2015-03-01

    A number of materials used in industry exhibit highly-scattering properties which can reduce the performance of conventional ultrasonic NDE approaches. Moving Bandwidth Polarity Thresholding (MBPT) is a robust frequency diversity based algorithm for scatter noise reduction in single A-scan waveforms, using sign coherence across a range of frequency bands to reduce grain noise and improve Signal to Noise Ratio. Importantly, for this approach to be extended to array applications, spatial variation of noise characteristics must also be considered. This paper presents a new spatial-frequency diversity based algorithm for array imaging, extended from MBPT. Each A-scan in the full matrix capture array dataset is partitioned into a serial of overlapped frequency bands and then undergoes polarity thresholding to generate sign-only coefficients indicating possible flaw locations within each selected band. These coefficients are synthesized to form a coefficient matrix using a delay and sum approach in each frequency band. Matrices produced across the frequency bands are then summed to generate a weighting matrix, which can be applied on any conventional image. A 5MHz linear array has been used to acquire data from both austenitic steel and high nickel alloy (HNA) samples to validate the proposed algorithm. Background noise is significantly suppressed for both samples after applying this approach. Importantly, three side drilled holes and the back wall of the HNA sample are clearly enhanced in the processed image, with a mean 133% Contrast to Noise Ratio improvement when compared to a conventional TFM image.

  17. The reverse abdominal reduction and the 'waistcoating' procedure for the correction of the fixated Pfannenstiel incision.

    Science.gov (United States)

    Harrison, Douglas H

    2016-05-01

    The principles of a standard abdominal reduction are well understood; this technique has been used for many years. However, a reverse abdominal reduction may be considered in some cases, for example, continued weight loss, and thus skin redundancy on the upper abdomen in patients who have already undergone abdominal reduction and upper abdomen improvement in patients requiring a mastopexy or breast reduction simultaneously. Reverse abdominal reduction is rarely mentioned in the medical literature, but it can prove successful; although the scar across the lower sternum has often been considered to be unsatisfactory, often it does not prove to be so. Thus, this procedure can be proven to be successful in suitable cases. Secondly, the Pfannenstiel incision, if not satisfactorily repaired in the first instance, can become fixated to the abdominal wall; this fixation along with the inevitable migration of skin and fat at its cephalic edge causes a rather displeasing contour defect when wearing tight-fitting swimwear. The principle of the waistcoating procedure is essentially to chamfer the fat cephalically; this procedure is employed for removing the Pfannenstiel scar from the abdominal wall. The principle is simple and effective and can be applied in cases with fixated scars. These two aforementioned principles are not commonly used, but they can prove particularly effective in suitable cases. We illustrate the principles.

  18. Doppler characteristics of sea clutter.

    Energy Technology Data Exchange (ETDEWEB)

    Raynal, Ann Marie; Doerry, Armin Walter

    2010-06-01

    Doppler radars can distinguish targets from clutter if the target's velocity along the radar line of sight is beyond that of the clutter. Some targets of interest may have a Doppler shift similar to that of clutter. The nature of sea clutter is different in the clutter and exo-clutter regions. This behavior requires special consideration regarding where a radar can expect to find sea-clutter returns in Doppler space and what detection algorithms are most appropriate to help mitigate false alarms and increase probability of detection of a target. This paper studies the existing state-of-the-art in the understanding of Doppler characteristics of sea clutter and scattering from the ocean to better understand the design and performance choices of a radar in differentiating targets from clutter under prevailing sea conditions.

  19. Treatment of abdominal cellulite and circumference reduction with radiofrequency and dynamic muscle activation.

    Science.gov (United States)

    Wanitphakdeedecha, Rungsima; Iamphonrat, Thanawan; Thanomkitti, Kanchalit; Lektrakul, Nittaya; Manuskiatti, Woraphong

    2015-01-01

    Cellulite is a frequent skin condition for which treatment remains a challenge. A wide variety of treatments are available but most procedures offer suboptimal clinical effect and/or delayed therapeutic outcome. Only few therapeutic options have proven efficacy in the treatment of cellulite. To determine the efficacy and the safety profiles of radiofrequency and dynamic muscle activation technology in treatment of abdominal cellulite and circumference reduction. Twenty-five females with abdominal cellulite received 6 weekly radiofrequency and dynamic muscle activation treatments. Treatment areas included the abdomen and both sides of flanks. Subjects were evaluated using standardized photographs, and measurements of body weight and abdominal circumference at baseline, before every treatment visit, and 1 week and four weeks after the final treatment. Subcutaneous tissue thickness was recorded by ultrasound at baseline and 4 weeks after completion of treatment protocol. Physicians' evaluation and patient's satisfaction of clinical improvement were also measured. All subjects completed the treatment protocol and attended every follow-up visits. There was significant abdominal circumference reduction of 2.96 and 2.52 cm at 1-, and 4-week follow-up visits (p cellulite appearance. The benefit of muscle activation is yet to be determined.

  20. Abdominal Respiration Induces Hemodilution and Related Reduction in ADH Concentration of Blood.

    Science.gov (United States)

    Kawai, Yoshiko; Ajima, Kumiko; Nagai, Takashi; Yokoyama, Yumiko; Kaidoh, Maki; Seto, Emi; Honda, Takayuki; Ohhashi, Toshio

    2015-09-01

    To establish effective lymph drainage methods and develop concise and accurate clinical techniques for evaluating lymph drainage in healthy individuals and patients with cancer treatment-related lymph edema, we investigated the numbers of red (RBC) and white (WBC) blood cells, and platelets (PLT) in blood, hematocrit (Ht), and the blood concentrations of total protein (TP), albumin (Alb), and anti-diuretic hormone (ADH) before and after 5 min manual lymph drainage, followed by 30 min rest with or without abdominal respiration in the supine or sitting position in 48 healthy volunteers. The 5 min facial, upper and lower extremities lymph drainage, followed by 30 min rest in the supine position induced significant reductions of the TP and Alb in all subjects, and their RBC and Ht levels in some subjects. The 30 min rest only in the supine position without lymph drainage produced also significant reductions of blood TP and Alb. In addition, abdominal respiration in the supine position without manual lymph drainage caused more significant hemodilution, being significant reductions of TP, Alb, RBC, Ht, and ADH in all volunteers. These findings may be related to effective lymph drainage from the chylocyst. Furthermore, it also resulted in a significantly increased micturition desire. In conclusion, abdominal respiration during 30 min rest in the supine position is effective at inducing lymph drainage, and the associated induction of hemodilution and lowering of the blood ADH concentration (and increased micturition desire in some cases) can be used to accurately assess the extent of lymph drainage.

  1. Dose reduction in pediatric abdominal CT: use of iterative reconstruction techniques across different CT platforms

    Energy Technology Data Exchange (ETDEWEB)

    Khawaja, Ranish Deedar Ali; Singh, Sarabjeet; Otrakji, Alexi; Padole, Atul; Lim, Ruth; Nimkin, Katherine; Westra, Sjirk; Kalra, Mannudeep K.; Gee, Michael S. [MGH Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States)

    2015-07-15

    Dose reduction in children undergoing CT scanning is an important priority for the radiology community and public at large. Drawbacks of radiation reduction are increased image noise and artifacts, which can affect image interpretation. Iterative reconstruction techniques have been developed to reduce noise and artifacts from reduced-dose CT examinations, although reconstruction algorithm, magnitude of dose reduction and effects on image quality vary. We review the reconstruction principles, radiation dose potential and effects on image quality of several iterative reconstruction techniques commonly used in clinical settings, including 3-D adaptive iterative dose reduction (AIDR-3D), adaptive statistical iterative reconstruction (ASIR), iDose, sinogram-affirmed iterative reconstruction (SAFIRE) and model-based iterative reconstruction (MBIR). We also discuss clinical applications of iterative reconstruction techniques in pediatric abdominal CT. (orig.)

  2. Radar clutter classification

    Science.gov (United States)

    Stehwien, Wolfgang

    1989-11-01

    The problem of classifying radar clutter as found on air traffic control radar systems is studied. An algorithm based on Bayes decision theory and the parametric maximum a posteriori probability classifier is developed to perform this classification automatically. This classifier employs a quadratic discriminant function and is optimum for feature vectors that are distributed according to the multivariate normal density. Separable clutter classes are most likely to arise from the analysis of the Doppler spectrum. Specifically, a feature set based on the complex reflection coefficients of the lattice prediction error filter is proposed. The classifier is tested using data recorded from L-band air traffic control radars. The Doppler spectra of these data are examined; the properties of the feature set computed using these data are studied in terms of both the marginal and multivariate statistics. Several strategies involving different numbers of features, class assignments, and data set pretesting according to Doppler frequency and signal to noise ratio were evaluated before settling on a workable algorithm. Final results are presented in terms of experimental misclassification rates and simulated and classified plane position indicator displays.

  3. Detection of Weather Radar Clutter

    DEFF Research Database (Denmark)

    Bøvith, Thomas

    2008-01-01

    Weather radars provide valuable information on precipitation in the atmosphere but due to the way radars work, not only precipitation is observed by the weather radar. Weather radar clutter, echoes from non-precipitating targets, occur frequently in the data, resulting in lowered data quality....... Especially in the application of weather radar data in quantitative precipitation estimation and forecasting a high data quality is important. Clutter detection is one of the key components in achieving this goal. This thesis presents three methods for detection of clutter. The methods use supervised...... and precipitating and non-precipitating clouds. Another method uses the difference in the motion field of clutter and precipitation measured between two radar images. Furthermore, the direction of the wind field extracted from a weather model is used. The third method uses information about the refractive index...

  4. Effects of a multidisciplinary body weight reduction program on static and dynamic thoraco-abdominal volumes in obese adolescents.

    Science.gov (United States)

    LoMauro, Antonella; Cesareo, Ambra; Agosti, Fiorenza; Tringali, Gabriella; Salvadego, Desy; Grassi, Bruno; Sartorio, Alessandro; Aliverti, Andrea

    2016-06-01

    The objective of this study was to characterize static and dynamic thoraco-abdominal volumes in obese adolescents and to test the effects of a 3-week multidisciplinary body weight reduction program (MBWRP), entailing an energy-restricted diet, psychological and nutritional counseling, aerobic physical activity, and respiratory muscle endurance training (RMET), on these parameters. Total chest wall (VCW), pulmonary rib cage (VRC,p), abdominal rib cage (VRC,a), and abdominal (VAB) volumes were measured on 11 male adolescents (Tanner stage: 3-5; BMI standard deviation score: >2; age: 15.9 ± 1.3 years; percent body fat: 38.4%) during rest, inspiratory capacity (IC) maneuver, and incremental exercise on a cycle ergometer at baseline and after 3 weeks of MBWRP. At baseline, the progressive increase in tidal volume was achieved by an increase in end-inspiratory VCW (p obese adolescents adopt a thoraco-abdominal operational pattern characterized by abdominal rib cage hyperinflation as a form of lung recruitment during incremental cycle exercise. Additionally, a short period of MBWRP including RMET is associated with improved exercise performance, lung and chest wall volume recruitment, unloading of respiratory muscles, and reduced dyspnea.

  5. Clutter Moves in Old Age Homecare

    DEFF Research Database (Denmark)

    Lutz, Peter

    2010-01-01

    This chapter introduces the notion of clutter moves as an experimental heuristic for tracing how movement threads together a range of cluttered entities in old age homecare ecologies. In particular it is concerned with older people and their cluttered technologies. It is based on empirical data...... cites general household clutter as a hazard in the domestic environment. In such reports moving around with cluttered things tends to threaten a dangerous outcome for older people. But what other feasible vistas emerge when the analytical attention is focused explicitly on relational movements between...

  6. Effects of adaptive statistical iterative reconstruction on radiation dose reduction and diagnostic accuracy of pediatric abdominal CT

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Sohi; Kim, Myung-Joon; Lee, Mi-Jung [Yonsei University College of Medicine, Department of Radiology and Research Institute of Radiological Science, Severance Children' s Hospital, Seoul (Korea, Republic of); Yoon, Choon-Sik [Yonsei University College of Medicine, Department of Radiology, Gangnam Severance Hospital, Seoul (Korea, Republic of); Kim, Dong Wook; Hong, Jung Hwa [Yonsei University College of Medicine, Biostatistics Collaboration Unit, Seoul (Korea, Republic of)

    2014-12-15

    Since children are more radio-sensitive than adults, there is a need to minimize radiation exposure during CT exams. To evaluate the effects of adaptive statistical iterative reconstruction (ASIR) on radiation dose reduction, image quality and diagnostic accuracy in pediatric abdominal CT. We retrospectively reviewed the abdominal CT examinations of 41 children (24 boys and 17 girls; mean age: 10 years) with a low-dose radiation protocol and reconstructed with ASIR (the ASIR group). We also reviewed routine-dose abdominal CT examinations of 41 age- and sex-matched controls reconstructed with filtered-back projection (control group). Image quality was assessed objectively as noise measured in the liver, spleen and aorta, as well as subjectively by three pediatric radiologists for diagnostic acceptability using a four-point scale. Radiation dose and objective image qualities of each group were compared with the paired t-test. Diagnostic accuracy was evaluated by reviewing follow-up imaging studies and medical records in 2012 and 2013. There was 46.3% dose reduction of size-specific dose estimates in ASIR group (from 13.4 to 7.2 mGy) compared with the control group. Objective noise was higher in the liver, spleen and aorta of the ASIR group (P < 0.001). However, the subjective image quality was average or superior in 84-100% of studies. Only one image was subjectively rated as unacceptable by one reviewer. There was only one case with interpretational error in the control group and none in the ASIR group. Use of the ASIR technique resulted in greater than a 45% reduction in radiation dose without impairing subjective image quality or diagnostic accuracy in pediatric abdominal CT, despite increased objective image noise. (orig.)

  7. Respiratory motion reduction in PET/CT using abdominal compression for lung cancer patients.

    Directory of Open Access Journals (Sweden)

    Tzung-Chi Huang

    Full Text Available PURPOSE: Respiratory motion causes substantial artifacts in reconstructed PET images when using helical CT as the attenuation map in PET/CT imaging. In this study, we aimed to reduce the respiratory artifacts in PET/CT images of patients with lung tumors using an abdominal compression device. METHODS: Twelve patients with lung cancer located in the middle or lower lobe of the lung were recruited. The patients were injected with 370 MBq of 18F-FDG. During PET, the patients assumed two bed positions for 1.5 min/bed. After conducting free-breathing imaging, we obtained images of the patients with abdominal compression by applying the same setup used in the free-breathing scan. The differences in the standardized uptake value (SUVmax, SUVmean, tumor volume, and the centroid of the tumors between PET and various CT schemes were measured. RESULTS: The SUVmax and SUVmean derived from PET/CT imaging using an abdominal compression device increased for all the lesions, compared with those obtained using the conventional approach. The percentage increases were 18.1% ±14% and 17% ±16.8% for SUVmax and SUVmean, respectively. PET/CT imaging combined with abdominal compression generally reduced the tumor mismatch between CT and the corresponding attenuation corrected PET images, with an average decrease of 1.9±1.7 mm over all the cases. CONCLUSIONS: PET/CT imaging combined with abdominal compression reduces respiratory artifacts and PET/CT misregistration, and enhances quantitative SUV in tumor. Abdominal compression is easy to set up and is an effective method used in PET/CT imaging for clinical oncology, especially in the thoracic region.

  8. New adaptive clutter rejection for ultrasound color Doppler imaging: in vivo study.

    Science.gov (United States)

    Yoo, Yang Mo; Kim, Yongmin

    2010-03-01

    Clutter rejection is essential for accurate flow estimation in ultrasound color Doppler imaging. In this article, we present a new adaptive clutter rejection (ACR) technique where an optimum filter is dynamically selected depending upon the underlying clutter characteristics (e.g., tissue acceleration and power). We compared the performance of the ACR method with other adaptive methods, i.e., down-mixing (DM) and adaptive clutter filtering (ACF), using in vivo data acquired from the kidney, liver and common carotid artery. With the kidney data, the ACR method provided an average improvement of 3.05 dB and 1.7 dB in flow signal-to-clutter ratio (SCR) compared with DM and ACF, respectively. With the liver data, SCR was improved by 2.75 dB and 1.8 dB over DM and ACF while no significant improvement with ACR was found in the common carotid artery data. Thus, the proposed adaptive method could provide more accurate flow estimation by improving clutter rejection in abdominal ultrasound color Doppler imaging pending validation.

  9. Magnetic Clutter Reduction Efficiency in Humanitarian Demining

    Science.gov (United States)

    2008-02-01

    opened, bottom casing exterior. Figure B.1 1.4 Type72b top casing with safety pin pulled. TNO report TNO-DV 2008 A064 Appendix B 1 3/10 Figure B. 11.5...Circuitry schematics for Type7lB anti personnel mine. From start-up, evoked by the removal of the safety pin , the mine gets into a (relatively) stable...possible that the mine can go off before that in the phase between 2 and 4 minutes after removing the safety pin . " ’+:3433 So V m.0+1mnn.m oT rOleob

  10. Clutter Moves in Old Age Homecare

    DEFF Research Database (Denmark)

    Lutz, Peter

    2010-01-01

    This chapter introduces the notion of clutter moves as an experimental heuristic for tracing how movement threads together a range of cluttered entities in old age homecare ecologies. In particular it is concerned with older people and their cluttered technologies. It is based on empirical data...... originating from an ethnographic study of old age homecare in the United States. Here the category of home clutter was revealed as more complex than it is commonly portrayed in popular or scholarly accounts, especially gerontology and geriatric–related literature on falling risks. This literature frequently...... cites general household clutter as a hazard in the domestic environment. In such reports moving around with cluttered things tends to threaten a dangerous outcome for older people. But what other feasible vistas emerge when the analytical attention is focused explicitly on relational movements between...

  11. An Ionospheric Es Layer Clutter Model and Suppression in HF Surfacewave Radar

    Directory of Open Access Journals (Sweden)

    Yajun Li

    2013-01-01

    Full Text Available This paper based on a fast implemented multiphase screen method using DFT puts forward an ionospheric Es layer clutter model and uses the newly developed dimensionality reduction space-time adaptive processing- (STAP- JDL algorithm to suppress Es layer clutter, which proves the validity of the proposed model. Firstly, the multiphase screen method was analyzed, and a fast algorithm using DFT was proposed. Then, based on the multiphase screen method and thorough simulation, we reached a conclusion of the high-frequency radio wave propagation’s fluctuation characteristics in the ionosphere. According to the results of the analysis, a new Es layer ionospheric clutter model was established and was compared with the measured data and verification was made. Finally, based on the built clutter model, JDL algorithm was applied to the high-frequency surface wave radar ionospheric clutter suppression, using the measured data to verify the validity of the model and algorithm. The simulation results showed that the built model can show the characteristics of the ionospheric Es layer clutter and that the JDL algorithm can suppress ionospheric Es layer clutter quite effectively.

  12. Dynamic Singularity Spectrum Distribution of Sea Clutter

    Science.gov (United States)

    Xiong, Gang; Yu, Wenxian; Zhang, Shuning

    2015-12-01

    The fractal and multifractal theory have provided new approaches for radar signal processing and target-detecting under the background of ocean. However, the related research mainly focuses on fractal dimension or multifractal spectrum (MFS) of sea clutter. In this paper, a new dynamic singularity analysis method of sea clutter using MFS distribution is developed, based on moving detrending analysis (DMA-MFSD). Theoretically, we introduce the time information by using cyclic auto-correlation of sea clutter. For transient correlation series, the instantaneous singularity spectrum based on multifractal detrending moving analysis (MF-DMA) algorithm is calculated, and the dynamic singularity spectrum distribution of sea clutter is acquired. In addition, we analyze the time-varying singularity exponent ranges and maximum position function in DMA-MFSD of sea clutter. For the real sea clutter data, we analyze the dynamic singularity spectrum distribution of real sea clutter in level III sea state, and conclude that the radar sea clutter has the non-stationary and time-varying scale characteristic and represents the time-varying singularity spectrum distribution based on the proposed DMA-MFSD method. The DMA-MFSD will also provide reference for nonlinear dynamics and multifractal signal processing.

  13. Comparing Image-Based Methods for Assessing Visual Clutter in Generalized Maps

    Science.gov (United States)

    Touya, G.; Decherf, B.; Lalanne, M.; Dumont, M.

    2015-08-01

    Map generalization abstracts and simplifies geographic information to derive maps at smaller scales. The automation of map generalization requires techniques to evaluate the global quality of a generalized map. The quality and legibility of a generalized map is related to the complexity of the map, or the amount of clutter in the map, i.e. the excessive amount of information and its disorganization. Computer vision research is highly interested in measuring clutter in images, and this paper proposes to compare some of the existing techniques from computer vision, applied to generalized maps evaluation. Four techniques from the literature are described and tested on a large set of maps, generalized at different scales: edge density, subband entropy, quad tree complexity, and segmentation clutter. The results are analyzed against several criteria related to generalized maps, the identification of cluttered areas, the preservation of the global amount of information, the handling of occlusions and overlaps, foreground vs background, and blank space reduction.

  14. COMPARING IMAGE-BASED METHODS FOR ASSESSING VISUAL CLUTTER IN GENERALIZED MAPS

    Directory of Open Access Journals (Sweden)

    G. Touya

    2015-08-01

    Full Text Available Map generalization abstracts and simplifies geographic information to derive maps at smaller scales. The automation of map generalization requires techniques to evaluate the global quality of a generalized map. The quality and legibility of a generalized map is related to the complexity of the map, or the amount of clutter in the map, i.e. the excessive amount of information and its disorganization. Computer vision research is highly interested in measuring clutter in images, and this paper proposes to compare some of the existing techniques from computer vision, applied to generalized maps evaluation. Four techniques from the literature are described and tested on a large set of maps, generalized at different scales: edge density, subband entropy, quad tree complexity, and segmentation clutter. The results are analyzed against several criteria related to generalized maps, the identification of cluttered areas, the preservation of the global amount of information, the handling of occlusions and overlaps, foreground vs background, and blank space reduction.

  15. Subaperture clutter filter with CFAR signal detection

    Energy Technology Data Exchange (ETDEWEB)

    Ormesher, Richard C.; Naething, Richard M.

    2016-08-30

    The various technologies presented herein relate to the determination of whether a received signal comprising radar clutter further comprises a communication signal. The communication signal can comprise of a preamble, a data symbol, communication data, etc. A first portion of the radar clutter is analyzed to determine a radar signature of the first portion of the radar clutter. A second portion of the radar clutter can be extracted based on the radar signature of the first portion. Following extraction, any residual signal can be analyzed to retrieve preamble data, etc. The received signal can be based upon a linear frequency modulation (e.g., a chirp modulation) whereby the chirp frequency can be determined and the frequency of transmission of the communication signal can be based accordingly thereon. The duration and/or bandwidth of the communication signal can be a portion of the duration and/or the bandwidth of the radar clutter.

  16. Reduction of chronic abdominal pain in patients with inflammatory bowel disease through transcranial direct current stimulation: a randomized controlled trial.

    Science.gov (United States)

    Volz, Magdalena S; Farmer, Annabelle; Siegmund, Britta

    2016-02-01

    Inflammatory bowel disease (IBD) is frequently associated with chronic abdominal pain (CAP). Transcranial direct current stimulation (tDCS) has been proven to reduce chronic pain. This study aimed to investigate the effects of tDCS in patients with CAP due to IBD. This randomized, sham-controlled, double blind, parallel-designed study included 20 patients with either Crohn disease or ulcerative colitis with CAP (≥3/10 on the visual analog scale (VAS) in 3/6 months). Anodal or sham tDCS was applied over the primary motor cortex for 5 consecutive days (2 mA, 20 minutes). Assessments included VAS, pressure pain threshold, inflammatory markers, and questionnaires on quality of life, functional and disease specific symptoms (Irritable Bowel Syndrome-Severity Scoring System [IBS-SSS]), disease activity, and pain catastrophizing. Follow-up data were collected 1 week after the end of the stimulation. Statistical analyses were performed using analysis of variance and t tests. There was a significant reduction of abdominal pain in the anodal tDCS group compared with sham tDCS. This effect was evident in changes in VAS and pressure pain threshold on the left and right sides of the abdomen. In addition, 1 week after stimulation, pain reduction remained significantly decreased in the right side of the abdomen. There was also a significant reduction in scores on pain catastrophizing and on IBS-SSS when comparing both groups. Inflammatory markers and disease activity did not differ significantly between groups throughout the experiment. Transcranial direct current stimulation proved to be an effective and clinically relevant therapeutic strategy for CAP in IBD. The analgesic effects observed are unrelated to inflammation and disease activity, which emphasizes central pain mechanisms in CAP.

  17. Cluttering

    Science.gov (United States)

    ... on December 4, 1955, in Levack, Ontario. Kenyon Martin Kenyon Martin, the basketball sensation who was named to the ... This Virginian congressman has served in the U.S. House of Representatives since 1981. The longtime supporter of ...

  18. Sensitivity study for clutter from reticle seekers

    Science.gov (United States)

    Conant, John A.

    1993-08-01

    The occurrence of background clutter is an on-going issue in the development of electro- optical sensors and seekers. Clutter varies with many parameters, which makes it costly to utilize measured data. Modeled backgrounds must be tested, however, to determine if the clutter they generate is realistic. The study reported here was performed with several goals: (1) to develop a methodology for studying clutter; (2) to compare the clutter levels from different scene elements; (3) study variations in spectral bandpass and in atmospheric visibility; and, (4) to study the effect of varying model sophistication on clutter. The last goal is one which has not previously been studied, to our knowledge. These results give model developers guidance on what model elements deserve the most resources. The present study focused on a generic reticle seeker, such as would be used in a tactical missile. The backgrounds studied were of tree-lines horizons, sun-heated rocks, and broken clouds, in four spectral bands within the 1 to 12 micron infrared region. Atmospheric haze levels were varied from 1 km to 23 km visibility. For these computations, the order of importance to clutter levels was, (1) scene type, (2) model sophistication level, and (3) haze. Strong variations with spectral band were also noted, although bands could not be compared fairly.

  19. Adjuvant Therapy for the Reduction of Postoperative Intra-abdominal Adhesion Formation

    Directory of Open Access Journals (Sweden)

    Jason PY Cheung

    2009-07-01

    Conclusions: Only a limited number of adjuvant treatment methods are currently available for the reduction of postoperative adhesions. Seprafilm has been proven to be the efficacious method to reduce adhesions. Investigations into the novel therapies are showing promising results in experimental studies and clinical studies before their wider application.

  20. Computational models for synthetic marine infrared clutter

    Science.gov (United States)

    Constantikes, Kim T.; Zysnarski, Adam H.

    1996-06-01

    The next generation of ship defense missiles will need to engage stealthy, passive, sea-skimming missiles. Detection and guidance will occur against a background of sea surface and horizon which can present significant clutter problems for infrared seekers, particularly when targets are comparatively dim. We need a variety of sea clutter models: statistical image models for signal processing algorithm design, clutter occurrence models for systems effectiveness assessment, and constructive image models for synthesizing very large field-of-view (FOV) images with high spatial and temporal resolution. We have implemented and tested such a constructive model. First principle models of water waves and light transport provide a computationally intensive clutter model implemented as a raytracer. Our models include sea, sky, and solar radiance; reflectance; attenuating atmospheres; constructive solid geometry targets; target and water wave dynamics; and simple sensor image formation.

  1. Efficacy of two different materials used in auricular acupressure on weight reduction and abdominal obesity.

    Science.gov (United States)

    Hsieh, Ching Hsiu; Su, Tsann-Juu; Fang, Yu-Wen; Chou, Pei-Hsuan

    2012-01-01

    The current study was designed to test the efficacy of different materials used in an auricular acupressure program on weight reduction, changes to waist circumference and waist-to-hip ratio. This study used a randomized design with two groups who were treated with auricular acupressure using Semen Vaccariae or the Japanese Magnetic Pearl. Both groups consisted of Asian young adults with a waist circumference ≥ 80 cm in the females and ≥ 90 cm in the males. At completion of the eight-week treatment period, the total sample size was 56 young adults who ranged in age from 18 to 20 years old. Each participant was met with weekly for ten-minute sessions during which ear acupressure treatment was performed. Sessions continued for eight weeks wherein both groups received acupressure with the Japanese Magnetic Pearl or Semen Vaccariae on the ear acupoints. While both groups showed significant reductions (p ≤ 0.05) to body weight and waist circumference after eight weeks of treatments, the group treated with Semen Vaccariae group showed a more effective weight loss over the short term. Given that auricular acupressure is a safe and cost-effective treatment for weight loss, our results suggest that auricular acupressure is a reasonable option for the treatment of overweight and obesity in young adults.

  2. Accelerated Singular Value-Based Ultrasound Blood Flow Clutter Filtering With Randomized Singular Value Decomposition and Randomized Spatial Downsampling.

    Science.gov (United States)

    Song, Pengfei; Trzasko, Joshua D; Manduca, Armando; Qiang, Bo; Kadirvel, Ramanathan; Kallmes, David F; Chen, Shigao

    2017-04-01

    Singular value decomposition (SVD)-based ultrasound blood flow clutter filters have recently demonstrated substantial improvement in clutter rejection for ultrafast plane wave microvessel imaging, and have become the commonly used clutter filtering method for many novel ultrafast imaging applications such as functional ultrasound and super-resolution imaging. At present, however, the computational burden of SVD remains as a major hurdle for practical implementation and clinical translation of this method. To address this challenge, in the study we present two blood flow clutter filtering methods based on randomized SVD (rSVD) and randomized spatial downsampling to accelerate SVD clutter filtering with minimal compromise to the clutter filter performance. rSVD accelerates SVD computation by approximating the k largest singular values, while random downsampling accelerates both full SVD and rSVD by decomposing the original large data matrix into small matrices that can be processed in parallel. An in vitro blood flow phantom study with the presence of heavy tissue clutter showed significantly improved computational performance using the proposed methods with minimal deterioration to the clutter filter performance (less than 3-dB reduction in blood to clutter ratio, less than 0.2-cm(2)/s(2) increase in flow mean squared error, less than 0.1-cm/s increase in the standard deviation of the vessel blood flow signal, and less than 0.3-cm/s increase in tissue clutter velocity for both full SVD and rSVD when the downsampling factor was less than 20× ). The maximum acceleration was about threefold from randomized spatial downsampling, and approximately another threefold from rSVD. An in vivo rabbit kidney perfusion study showed that rSVD provided comparable performance to full SVD in clutter rejection in vivo (maximum difference of blood to clutter ratio was less than 0.6 dB), and random downsampling provided artifact-free perfusion imaging results when combined with both

  3. Sea clutter scattering, the K distribution and radar performance

    CERN Document Server

    Ward, Keith; Watts, Simon

    2013-01-01

    Sea Clutter: Scattering, the K Distribution and Radar Performance, 2nd Edition gives an authoritative account of our current understanding of radar sea clutter. Topics covered include the characteristics of radar sea clutter, modelling radar scattering by the ocean surface, statistical models of sea clutter, the simulation of clutter and other random processes, detection of small targets in sea clutter, imaging ocean surface features, radar detection performance calculations, CFAR detection, and the specification and measurement of radar performance. The calculation of the performance of pract

  4. Bumblebee flight performance in cluttered environments: effects of obstacle orientation, body size and acceleration.

    Science.gov (United States)

    Crall, James D; Ravi, Sridhar; Mountcastle, Andrew M; Combes, Stacey A

    2015-09-01

    Locomotion through structurally complex environments is fundamental to the life history of most flying animals, and the costs associated with movement through clutter have important consequences for the ecology and evolution of volant taxa. However, few studies have directly investigated how flying animals navigate through cluttered environments, or examined which aspects of flight performance are most critical for this challenging task. Here, we examined how body size, acceleration and obstacle orientation affect the flight of bumblebees in an artificial, cluttered environment. Non-steady flight performance is often predicted to decrease with body size, as a result of a presumed reduction in acceleration capacity, but few empirical tests of this hypothesis have been performed in flying animals. We found that increased body size is associated with impaired flight performance (specifically transit time) in cluttered environments, but not with decreased peak accelerations. In addition, previous studies have shown that flying insects can produce higher accelerations along the lateral body axis, suggesting that if maneuvering is constrained by acceleration capacity, insects should perform better when maneuvering around objects laterally rather than vertically. Our data show that bumblebees do generate higher accelerations in the lateral direction, but we found no difference in their ability to pass through obstacle courses requiring lateral versus vertical maneuvering. In sum, our results suggest that acceleration capacity is not a primary determinant of flight performance in clutter, as is often assumed. Rather than being driven by the scaling of acceleration, we show that the reduced flight performance of larger bees in cluttered environments is driven by the allometry of both path sinuosity and mean flight speed. Specifically, differences in collision-avoidance behavior underlie much of the variation in flight performance across body size, with larger bees

  5. Radiation dose reduction sinogram affirmed iterative reconstruction and automatic tube voltage modulation(CARE kV) in abdominal CT

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Hyun Joo; Chung, Yong Eun; Lee, Young Han; Choi, Jin Young; Park, Mi Suk; Kim, Myeong Jin; Kim, Ki Whang [Dept. of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2013-12-15

    To evaluate the feasibility of sinogram-affirmed iterative reconstruction (SAFIRE) and automated kV modulation (CARE kV) in reducing radiation dose without increasing image noise for abdominal CT examination. This retrospective study included 77 patients who received CT imaging with an application of CARE kV with or without SAFIRE and who had comparable previous CT images obtained without CARE kV or SAFIRE, using the standard dose (i.e., reference mAs of 240) on an identical CT scanner and reconstructed with filtered back projection (FBP) within 1 year. Patients were divided into two groups: group A (33 patients, CT scanned with CARE kV); and group B (44 patients, scanned after reducing the reference mAs from 240 to 170 and applying both CARE kV and SAFIRE). CT number, image noise for four organs and radiation dose were compared among the two groups. Image noise increased after CARE kV application (p < 0.001) and significantly decreased as SAFIRE strength increased (p < 0.001). Image noise with reduced-mAs scan (170 mAs) in group B became similar to that of standard-dose FBP images after applying CARE kV and SAFIRE strengths of 3 or 4 when measured in the aorta, liver or muscle (p ≥ 0.108). Effective doses decreased by 19.4% and 41.3% for groups A and B, respectively (all, p < 0.001) after application of CARE kV with or without SAFIRE. Combining CARE kV, reduction of mAs from 240 to 170 mAs and noise reduction by applying SAFIRE strength 3 or 4 reduced the radiation dose by 41.3% without increasing image noise compared with the standard-dose FBP images.

  6. 2006 Fynmeet sea clutter measurement trial: Datasets

    CSIR Research Space (South Africa)

    Herselman, PLR

    2007-09-06

    Full Text Available 3000 3200 3400 3600 -30 -25 -20 -15 -10 -5 0 5 10 15 Experiment Summary Value Radar Setup Value Type Sea Clutter Tx Frequency 9.125 GHz Date 31-Jul-2006 PRF 5 kHz Start Time 15:45:38.468 Tracking Range 2300 m Duration 183090 PRI's (36.6178 s... 15 Experiment Summary Value Radar Setup Value Type Sea Clutter Tx Frequency 9.125 GHz Date 31-Jul-2006 PRF 5 kHz Start Time 15:46:15.103 Tracking Range 2300 m Duration 212925 PRI's (42.5848 s) Range Extend 1440 m (96 gates), 15 m res...

  7. Analysis of Sea Spikes in Radar Sea Clutter Data

    NARCIS (Netherlands)

    Melief, H.W.; Greidanus, H.; Genderen, P. van; Hoogeboom, P.

    2006-01-01

    Abstract—In this paper three sets of high-resolution, coherent, and polarimetric radar sea clutter data are analyzed and compared with radar sea clutter models. The nature of the data allows a thorough analysis of the power, polarization and velocity of the sea clutter. It is shown that these

  8. Analysis of Sea Spikes in Radar Sea Clutter Data

    NARCIS (Netherlands)

    Melief, H.W.; Greidanus, H.; Genderen, P. van; Hoogeboom, P.

    2006-01-01

    Abstract—In this paper three sets of high-resolution, coherent, and polarimetric radar sea clutter data are analyzed and compared with radar sea clutter models. The nature of the data allows a thorough analysis of the power, polarization and velocity of the sea clutter. It is shown that these quanti

  9. Non-contact radiofrequency-induced reduction of subcutaneous abdominal fat correlates with initial cardiovascular autonomic balance and fat tissue hormones: safety analysis.

    Science.gov (United States)

    Pumprla, Jiri; Howorka, Kinga; Kolackova, Zuzana; Sovova, Eliska

    2015-01-01

    The non-invasive reduction of subcutaneous abdominal fat became popular in the last decade. Radiofrequency (RF), non-contact, selective-field device Vanquish® has been developed to selectively induce deep fat tissue heating to reduce waist circumference. Our analysis evaluates immediate and sustained effects of this treatment on cardiovascular autonomic function and on selected metabolic parameters. Study design/ patients and methods: A retrospective proof-of-concept analysis of RF treatment effects was conducted in 20 individuals with metabolic syndrome, to reduce the subcutaneous abdominal fat. Four 30-minutes treatment sessions (manufacturer´s standard protocol) were performed in 1-week intervals. Vital signs, ECG, lab screening, body composition, subcutaneous fat thickness and spectral analysis of heart rate variability (HRV) have been examined before, after the 1 (st) and 4 (th) treatment, and at follow-up visits 1 month and 3 months after the treatment. The RF treatment led to a significant reduction of abdominal circumference after the 4 (th) session (p0.59, pfat. While the treatment increases the immediate sympathetic response of the body to deep tissue heating, no sustained change in autonomic function could be recorded at 1 month follow-up. The observed correlation between initial VLF spectral power and waist circumference reduction at follow-up, as well as the association of initial adiponectin values and immediate autonomic response to the treatment might be instrumental for decisions on body contouring strategies.

  10. Infrared clutter measurements of marine backgrounds

    NARCIS (Netherlands)

    Schwering, Piet B.

    1991-01-01

    Observations in the infrared wavelength band between 8 and 12 μm of sea backgrounds have been recorded with a CCIR compatible imager for a large number of sea states (0 - 6). Recordings took place in coastal areas as well as on open seas. The behavior of clutter in the infrared data was analyzed in

  11. Comparable Effects of High-Intensity Interval Training and Prolonged Continuous Exercise Training on Abdominal Visceral Fat Reduction in Obese Young Women

    Directory of Open Access Journals (Sweden)

    Haifeng Zhang

    2017-01-01

    Full Text Available This study compared the effect of prolonged moderate-intensity continuous training (MICT on reducing abdominal visceral fat in obese young women with that of work-equivalent (300 kJ/training session high-intensity interval training (HIIT. Forty-three participants received either HIIT (n=15, MICT (n=15, or no training (CON, n=13 for 12 weeks. The abdominal visceral fat area (AVFA and abdominal subcutaneous fat area (ASFA of the participants were measured through computed tomography scans preintervention and postintervention. Total fat mass and the fat mass of the android, gynoid, and trunk regions were assessed through dual-energy X-ray absorptiometry. Following HIIT and MICT, comparable reductions in AVFA (−9.1, −9.2 cm2, ASFA (−35, −28.3 cm2, and combined AVFA and ASFA (−44.7, −37.5 cm2, p>0.05 were observed. Similarly, reductions in fat percentage (−2.5%, −2.4%, total fat mass (−2.8, −2.8 kg, and fat mass of the android (−0.3, −0.3 kg, gynoid (−0.5, −0.7 kg, and trunk (−1.6, −1.2 kg, p>0.05 regions did not differ between HIIT and MICT. No variable changed in CON. In conclusion, MICT consisting of prolonged sessions has no quantitative advantage, compared with that resulting from HIIT, in abdominal visceral fat reduction. HIIT appears to be the predominant strategy for controlling obesity because of its time efficiency.

  12. Comparable Effects of High-Intensity Interval Training and Prolonged Continuous Exercise Training on Abdominal Visceral Fat Reduction in Obese Young Women

    Science.gov (United States)

    Zhang, Haifeng; Tong, Tom K.; Qiu, Weifeng; Zhang, Xu; Zhou, Shi

    2017-01-01

    This study compared the effect of prolonged moderate-intensity continuous training (MICT) on reducing abdominal visceral fat in obese young women with that of work-equivalent (300 kJ/training session) high-intensity interval training (HIIT). Forty-three participants received either HIIT (n = 15), MICT (n = 15), or no training (CON, n = 13) for 12 weeks. The abdominal visceral fat area (AVFA) and abdominal subcutaneous fat area (ASFA) of the participants were measured through computed tomography scans preintervention and postintervention. Total fat mass and the fat mass of the android, gynoid, and trunk regions were assessed through dual-energy X-ray absorptiometry. Following HIIT and MICT, comparable reductions in AVFA (−9.1, −9.2 cm2), ASFA (−35, −28.3 cm2), and combined AVFA and ASFA (−44.7, −37.5 cm2, p > 0.05) were observed. Similarly, reductions in fat percentage (−2.5%, −2.4%), total fat mass (−2.8, −2.8 kg), and fat mass of the android (−0.3, −0.3 kg), gynoid (−0.5, −0.7 kg), and trunk (−1.6, −1.2 kg, p > 0.05) regions did not differ between HIIT and MICT. No variable changed in CON. In conclusion, MICT consisting of prolonged sessions has no quantitative advantage, compared with that resulting from HIIT, in abdominal visceral fat reduction. HIIT appears to be the predominant strategy for controlling obesity because of its time efficiency. PMID:28116314

  13. Tuberculosis abdominal Abdominal tuberculosis

    OpenAIRE

    Rubio, T.; M. T. Gaztelu; Calvo, A.; M. Repiso; H. Sarasíbar; F. Jiménez Bermejo; A. Martínez Echeverría

    2005-01-01

    La tuberculosis abdominal cursa con un cuadro inespecífico, con difícil diagnóstico diferencial respecto a otras entidades de similar semiología. Presentamos el caso de un varón que ingresa por presentar dolor abdominal, pérdida progresiva y notoria de peso corporal y fiebre de dos meses de evolución. El cultivo de la biopsia de colon mostró presencia de bacilo de Koch.Abdominal tuberculosis develops according to a non-specific clinical picture, with a difficult differential diagnosis with re...

  14. Suppression of Clutter Near Port by S-Band Radar

    Science.gov (United States)

    Ishii, Seishiro; Sayama, Syuji

    It was reported that various radar clutters obey a Weibull distribution under certain conditions. To suppress such Weibull-distributed clutter, a new adaptive method was proposed by the present authors. In this method, the parameters of the Weibull distribution and the threshold level for an adaptive Constant False Alarm Rate (CFAR) detector are determined by calculating the variance after it passed through a logarithmic amplifier. To apply this new method to practical problems observed by an S-band radar, computer simulation were made for a finite number of samples in order to obtain the CFAR maintenance in Weibull radar clutter which was including sea clutter and ground clutter from a variety of terrain near the port. Finally an improvement value of target-to-clutter ratio 49.5dB was obtained for the detection of ships embedded in sea clutter near the port.

  15. Overview and Prospects of Research on Sea Clutter Property Cognition

    Directory of Open Access Journals (Sweden)

    Ding Hao

    2016-10-01

    Full Text Available Sea clutter is one of the main limiting factors influencing the target detection performance of nautical radars. The physical mechanism of sea clutter is complex with an abundance of influencing factors, and the non-Gaussian as well as non-stationarity behavior is significant. Thus, research into sea clutter property cognition is complicated and has to be systematic. Based on research that concentrates on experimental data, this paper reviews and summarizes the research developments in sea clutter property cognition. It concentrates on the properties that are of most interest for target detection algorithms: amplitude distribution, spectra, correlation, and non-stationarity and nonlinearity. The main research results are also concluded. Based on this, four aspects of problems that need further exploration are highlighted and include the following: further analysis of sea clutter influencing factors; the game problem between sea clutter precision modeling and the requirements of detection algorithms; and the property cognition between radar target and sea clutter.

  16. Patterns of Brain Activation and Meal Reduction Induced by Abdominal Surgery in Mice and Modulation by Rikkunshito.

    Science.gov (United States)

    Wang, Lixin; Mogami, Sachiko; Yakabi, Seiichi; Karasawa, Hiroshi; Yamada, Chihiro; Yakabi, Koji; Hattori, Tomohisa; Taché, Yvette

    2015-01-01

    Abdominal surgery inhibits food intake and induces c-Fos expression in the hypothalamic and medullary nuclei in rats. Rikkunshito (RKT), a Kampo medicine improves anorexia. We assessed the alterations in meal microstructure and c-Fos expression in brain nuclei induced by abdominal surgery and the modulation by RKT in mice. RKT or vehicle was gavaged daily for 1 week. On day 8 mice had no access to food for 6-7 h and were treated twice with RKT or vehicle. Abdominal surgery (laparotomy-cecum palpation) was performed 1-2 h before the dark phase. The food intake and meal structures were monitored using an automated monitoring system for mice. Brain sections were processed for c-Fos immunoreactivity (ir) 2-h after abdominal surgery. Abdominal surgery significantly reduced bouts, meal frequency, size and duration, and time spent on meals, and increased inter-meal interval and satiety ratio resulting in 92-86% suppression of food intake at 2-24 h post-surgery compared with control group (no surgery). RKT significantly increased bouts, meal duration and the cumulative 12-h food intake by 11%. Abdominal surgery increased c-Fos in the prelimbic, cingulate and insular cortexes, and autonomic nuclei, such as the bed nucleus of the stria terminalis, central amygdala, hypothalamic supraoptic (SON), paraventricular and arcuate nuclei, Edinger-Westphal nucleus (E-W), lateral periaqueduct gray (PAG), lateral parabrachial nucleus, locus coeruleus, ventrolateral medulla and nucleus tractus solitarius (NTS). RKT induced a small increase in c-Fos-ir neurons in the SON and E-W of control mice, and in mice with surgery there was an increase in the lateral PAG and a decrease in the NTS. These findings indicate that abdominal surgery inhibits food intake by increasing both satiation (meal duration) and satiety (meal interval) and activates brain circuits involved in pain, feeding behavior and stress that may underlie the alterations of meal pattern and food intake inhibition. RKT improves

  17. Patterns of Brain Activation and Meal Reduction Induced by Abdominal Surgery in Mice and Modulation by Rikkunshito.

    Directory of Open Access Journals (Sweden)

    Lixin Wang

    Full Text Available Abdominal surgery inhibits food intake and induces c-Fos expression in the hypothalamic and medullary nuclei in rats. Rikkunshito (RKT, a Kampo medicine improves anorexia. We assessed the alterations in meal microstructure and c-Fos expression in brain nuclei induced by abdominal surgery and the modulation by RKT in mice. RKT or vehicle was gavaged daily for 1 week. On day 8 mice had no access to food for 6-7 h and were treated twice with RKT or vehicle. Abdominal surgery (laparotomy-cecum palpation was performed 1-2 h before the dark phase. The food intake and meal structures were monitored using an automated monitoring system for mice. Brain sections were processed for c-Fos immunoreactivity (ir 2-h after abdominal surgery. Abdominal surgery significantly reduced bouts, meal frequency, size and duration, and time spent on meals, and increased inter-meal interval and satiety ratio resulting in 92-86% suppression of food intake at 2-24 h post-surgery compared with control group (no surgery. RKT significantly increased bouts, meal duration and the cumulative 12-h food intake by 11%. Abdominal surgery increased c-Fos in the prelimbic, cingulate and insular cortexes, and autonomic nuclei, such as the bed nucleus of the stria terminalis, central amygdala, hypothalamic supraoptic (SON, paraventricular and arcuate nuclei, Edinger-Westphal nucleus (E-W, lateral periaqueduct gray (PAG, lateral parabrachial nucleus, locus coeruleus, ventrolateral medulla and nucleus tractus solitarius (NTS. RKT induced a small increase in c-Fos-ir neurons in the SON and E-W of control mice, and in mice with surgery there was an increase in the lateral PAG and a decrease in the NTS. These findings indicate that abdominal surgery inhibits food intake by increasing both satiation (meal duration and satiety (meal interval and activates brain circuits involved in pain, feeding behavior and stress that may underlie the alterations of meal pattern and food intake inhibition

  18. Adaptive clutter rejection for ultrasound color Doppler imaging

    Science.gov (United States)

    Yoo, Yang Mo; Managuli, Ravi; Kim, Yongmin

    2005-04-01

    We have developed a new adaptive clutter rejection technique where an optimum clutter filter is dynamically selected according to the varying clutter characteristics in ultrasound color Doppler imaging. The selection criteria have been established based on the underlying clutter characteristics (i.e., the maximum instantaneous clutter velocity and the clutter power) and the properties of various candidate clutter filters (e.g., projection-initialized infinite impulse response and polynomial regression). We obtained an average improvement of 3.97 dB and 3.27 dB in flow signal-to-clutter-ratio (SCR) compared to the conventional and down-mixing methods, respectively. These preliminary results indicate that the proposed adaptive clutter rejection method could improve the sensitivity and accuracy in flow velocity estimation for ultrasound color Doppler imaging. For a 192 x 256 color Doppler image with an ensemble size of 10, the proposed method takes only 57.2 ms, which is less than the acquisition time. Thus, the proposed method could be implemented in modern ultrasound systems, while providing improved clutter rejection and more accurate velocity estimation in real time.

  19. Clutter discrimination algorithm simulation in pulse laser radar imaging

    Science.gov (United States)

    Zhang, Yan-mei; Li, Huan; Guo, Hai-chao; Su, Xuan; Zhu, Fule

    2015-10-01

    Pulse laser radar imaging performance is greatly influenced by different kinds of clutter. Various algorithms are developed to mitigate clutter. However, estimating performance of a new algorithm is difficult. Here, a simulation model for estimating clutter discrimination algorithms is presented. This model consists of laser pulse emission, clutter jamming, laser pulse reception and target image producing. Additionally, a hardware platform is set up gathering clutter data reflected by ground and trees. The data logging is as clutter jamming input in the simulation model. The hardware platform includes a laser diode, a laser detector and a high sample rate data logging circuit. The laser diode transmits short laser pulses (40ns FWHM) at 12.5 kilohertz pulse rate and at 905nm wavelength. An analog-to-digital converter chip integrated in the sample circuit works at 250 mega samples per second. The simulation model and the hardware platform contribute to a clutter discrimination algorithm simulation system. Using this system, after analyzing clutter data logging, a new compound pulse detection algorithm is developed. This new algorithm combines matched filter algorithm and constant fraction discrimination (CFD) algorithm. Firstly, laser echo pulse signal is processed by matched filter algorithm. After the first step, CFD algorithm comes next. Finally, clutter jamming from ground and trees is discriminated and target image is produced. Laser radar images are simulated using CFD algorithm, matched filter algorithm and the new algorithm respectively. Simulation result demonstrates that the new algorithm achieves the best target imaging effect of mitigating clutter reflected by ground and trees.

  20. Unified sensor management in unknown dynamic clutter

    Science.gov (United States)

    Mahler, Ronald; El-Fallah, Adel

    2010-04-01

    In recent years the first author has developed a unified, computationally tractable approach to multisensor-multitarget sensor management. This approach consists of closed-loop recursion of a PHD or CPHD filter with maximization of a "natural" sensor management objective function called PENT (posterior expected number of targets). In this paper we extend this approach so that it can be used in unknown, dynamic clutter backgrounds.

  1. Comparison of diagnostic performance between single- and multiphasic contrast-enhanced abdominopelvic computed tomography in patients admitted to the emergency department with abdominal pain: potential radiation dose reduction

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Shin Hye; You, Je Sung; Choi, Jin-Young; Kim, Myeong-Jin; Chung, Yong Eun [Yonsei University College of Medicine, Department of Radiology, Research Institute of Radiological Science, Seodaemun-gu, Seoul (Korea, Republic of); Song, Mi Kyong [Yonsei University, Biostatistics Collaboration Unit, College of Medicine, Seoul (Korea, Republic of)

    2015-04-01

    To evaluate feasibility of radiation dose reduction by optimal phase selection of computed tomography (CT) in patients who visited the emergency department (ED) for abdominal pain. We included 253 patients who visited the ED for abdominal pain. They underwent multiphasic CT including precontrast, late arterial phase (LAP), and hepatic venous phase (HVP). Three image sets (HVP, precontrast + HVP, and precontrast + LAP + HVP) were reviewed. Two reviewers determined the most appropriate diagnosis with five-point confidence scale. Diagnostic performances were compared among image sets by weighted-least-squares method or DeLong's method. Linear mixed model was used to assess changes of diagnostic confidence and radiation dose. There was no difference in diagnostic performance among three image sets, although diagnostic confidence level was significantly improved after review of triphasic images compared with both HVP images only or HVP with precontrast images (confidence scale, 4.64 ± 0.05, 4.66 ± 0.05, and 4.76 ± 0.04 in the order of the sets; overall P = 0.0008). Similar trends were observed in the subgroup analysis for diagnosis of pelvic inflammatory disease and cholecystitis. There is no difference between HVP-CT alone and multiphasic CT for the diagnosis of causes of abdominal pain in patients admitted to the ED without prior chronic disease or neoplasia. (orig.)

  2. Performance Analysis of Two CFAR Detectors in Clutter Edge Situation

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This paper studies the performance of the GOSGO and GOSSO CFAR detectors [1] in clutter edge situation. The authors derive the analytic expressions of the false alarm probabilities in that situation, analyze their performances against clutter edge, and compare them with the OS, CA, GO and SO detectors. The results show that GOSGO possesses better performance than GO for countering clutter, but the performance of GOSSO is very unideal.

  3. Application of phase coherent transform to cloud clutter suppression

    Energy Technology Data Exchange (ETDEWEB)

    Ng, L.C. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    This paper describes a tracking algorithm using frame-to-frame correlation with frequency domain clutter suppression. Clutter suppression was mechanized via a `Phase Coherent Transform` (PCT) approach. This approach was applied to explore the feasibility of tracking a post-boost rocket from a low earth orbit satellite with real cloud background data. Simulation results show that the PCT/correlation tracking algorithm can perform satisfactorily at signal-to-clutter ratio (SCR) as low as 5 or 7 dB.

  4. Reduction of contrast medium volume in abdominal aorta CTA: Multiphasic injection technique versus a test bolus volume

    Energy Technology Data Exchange (ETDEWEB)

    Nijhof, Wouter H., E-mail: w.h.nijhof@student.utwente.nl [University of Twente, MIRA-Institute for Biomedical Technology and Technical Medicine, P.O. Box 21, 7500 AE Enschede (Netherlands); Vos, Charlotte S. van der, E-mail: c.s.vandervos@student.utwente.nl [University of Twente, MIRA-Institute for Biomedical Technology and Technical Medicine, P.O. Box 21, 7500 AE Enschede (Netherlands); Anninga, Bauke, E-mail: b.anninga@student.utwente.nl [University of Twente, MIRA-Institute for Biomedical Technology and Technical Medicine, P.O. Box 21, 7500 AE Enschede (Netherlands); Jager, Gerrit J., E-mail: g.jager@JBZ.nl [Department of Radiology, Jeroen Bosch Hospital, Henri Dunantstraat 1, 5223 GZ ’s-Hertogenbosch (Netherlands); Rutten, Matthieu J.C.M., E-mail: mj.rutten@online.nl [Department of Radiology, Jeroen Bosch Hospital, Henri Dunantstraat 1, 5223 GZ ’s-Hertogenbosch (Netherlands)

    2013-09-15

    Objective: The purpose of this study is to reduce the administered contrast medium volume in abdominal CTA by using a test bolus injection, with the preservation of adequate quantitative and qualitative vessel enhancement. Study design: For this technical efficacy study 30 patients, who were referred for a CTA examination of the abdominal aorta, were included. Randomly 15 patients were assigned to undergo a multiphasic injection protocol and received 89 mL of contrast medium (Optiray 350) (protocol I). Fifteen patients were assigned to the test bolus injection protocol (protocol II), which implies injection of a 10 mL test bolus of Optiray 350 prior to performing CTA with a 40 mL of contrast medium. Quantitative assessment of vascular enhancement was performed by measuring the amount of Hounsfield Units in the aorta at 30 positions from the celiac trunk to the iliac arteries in both groups. Qualitative assessment was performed by three radiologists who scored the images at a 5-point scale. Results: Quantitative assessment showed that there was no significant difference in vascular enhancement for patients between the two protocols, with mean attenuation values of 280.9 ± 50.84 HU and 258.60 ± 39.28 HU, respectively. The image quality of protocol I was rated 4.31 (range: 3.67/5.00) and of protocol II 4.11 (range: 2.67/5.00). These differences were not statistically significant. Conclusion: This study showed that by using a test bolus injection and the administration of 50 mL of contrast medium overall, CTA of the abdominal aorta can reliably be performed, with regard to quantitative and qualitative adequate vessel enhancement.

  5. The neurological underpinnings of cluttering: Some initial findings.

    Science.gov (United States)

    Ward, David; Connally, Emily L; Pliatsikas, Christos; Bretherton-Furness, Jess; Watkins, Kate E

    2015-03-01

    Cluttering is a fluency disorder characterised by overly rapid or jerky speech patterns that compromise intelligibility. The neural correlates of cluttering are unknown but theoretical accounts implicate the basal ganglia and medial prefrontal cortex. Dysfunction in these brain areas would be consistent with difficulties in selection and control of speech motor programs that are characteristic of speech disfluencies in cluttering. There is a surprising lack of investigation into this disorder using modern imaging techniques. Here, we used functional MRI to investigate the neural correlates of cluttering. We scanned 17 adults who clutter and 17 normally fluent control speakers matched for age and sex. Brain activity was recorded using sparse-sampling functional MRI while participants viewed scenes and either (i) produced overt speech describing the scene or (ii) read out loud a sentence provided that described the scene. Speech was recorded and analysed off line. Differences in brain activity for each condition compared to a silent resting baseline and between conditions were analysed for each group separately (cluster-forming threshold Z>3.1, extent p30 voxels, uncorrected). In both conditions, the patterns of activation in adults who clutter and control speakers were strikingly similar, particularly at the cortical level. Direct group comparisons revealed greater activity in adults who clutter compared to control speakers in the lateral premotor cortex bilaterally and, as predicted, on the medial surface (pre-supplementary motor area). Subcortically, adults who clutter showed greater activity than control speakers in the basal ganglia. Specifically, the caudate nucleus and putamen were overactive in adults who clutter for the comparison of picture description with sentence reading. In addition, adults who clutter had reduced activity relative to control speakers in the lateral anterior cerebellum bilaterally. Eleven of the 17 adults who clutter also stuttered

  6. Effects of Video Exposure to Cluttering on Undergraduate Students' Perceptions of a Person Who Clutters

    Science.gov (United States)

    Farrell, Lindsey M.; Blanchet, Paul G.; Tillery, Kim L.

    2015-01-01

    Background: Previous research suggests a negative stereotype toward people with fluency disorders (i.e. stuttering and/or cluttering), although recent findings suggest that exposure to an actual person who stutters (e.g. a live or video presentation) leads to more positive perceptions of some personality traits. However, there is a paucity of…

  7. Polarimetric clutter modeling: Theory and application

    Science.gov (United States)

    Kong, J. A.; Lin, F. C.; Borgeaud, M.; Yueh, H. A.; Swartz, A. A.; Lim, H. H.; Shim, R. T.; Novak, L. M.

    1988-01-01

    The two-layer anisotropic random medium model is used to investigate fully polarimetric scattering properties of earth terrain media. The polarization covariance matrices for the untilted and tilted uniaxial random medium are evaluated using the strong fluctuation theory and distorted Born approximation. In order to account for the azimuthal randomness in the growth direction of leaves in tree and grass fields, an averaging scheme over the azimuthal direction is also applied. It is found that characteristics of terrain clutter can be identified through the analysis of each element of the covariance matrix. Theoretical results are illustrated by the comparison with experimental data provided by MIT Lincoln Laboratory for tree and grass fields.

  8. Increased clutter level in echocardiography due to specular reflection

    Science.gov (United States)

    Fatemi, Ali; Torp, Hans; Aakhus, Svend; Rodriguez-Molares, Alfonso

    2017-03-01

    State-of-the-art echocardiography allows to correctly diagnose most of cardiovascular diseases. An unknown source of clutter, however, hinders the visualization of the heart in some cases. We believe this clutter is caused by the ultrasound beam being partially reflected by the ribs into the elevation direction, so that structures outside the imaging plane are displayed on top of the heart image as clutter noise. We conducted in vitro experiments in a water tank using a synthetic ventricle and pig ribs. By partially blocking the probe with the ribs in the elevation direction, objects outside the imaging plane were rendered in the B-mode image, which confirms that the ribs can behave as specular reflectors. In addition, we succeeded in reproducing clutter noise using a piece of polystyrene to simulate the reflections from the lungs. This indicates that the origin of the clutter noise in echocardiograms can be reverberation coming from the lungs via specular reflection at the ribs.

  9. Distributed Fuzzy CFAR Detection for Weibull Clutter

    Science.gov (United States)

    Zaimbashi, Amir; Taban, Mohammad Reza; Nayebi, Mohammad Mehdi

    In Distributed detection systems, restricting the output of the local decision to one bit certainly implies a substantial information loss. In this paper, we consider the fuzzy detection, which uses a function called membership function for mapping the observation space of each local detector to a value between 0 and 1, indicating the degree of assurance about presence or absence of a signal. In this case, we examine the problem of distributed Maximum Likelihood (ML) and Order Statistic (OS) constant false alarm rate (CFAR) detections using fuzzy fusion rules such as “Algebraic Product” (AP), “Algebraic Sum” (AS), “Union” (Un) and “Intersection” (IS) in the fusion centre. For the Weibull clutter, the expression of the membership function based on the ML or OS CFAR processors in the local detectors is also obtained. For comparison, we consider a binary distributed detector, which uses the Maximum Likelihood and Algebraic Product (MLAP) or Order Statistic and Algebraic Product (OSAP) CFAR processors as the local detectors. In homogenous and non homogenous situations, multiple targets or clutter edge, the performances of the fuzzy and binary distributed detectors are analyzed and compared. The simulation results indicate the superior and robust performance of the distributed systems using fuzzy detection in the homogenous and non homogenous situations.

  10. The adaptive statistical iterative reconstruction-V technique for radiation dose reduction in abdominal CT: comparison with the adaptive statistical iterative reconstruction technique.

    Science.gov (United States)

    Kwon, Heejin; Cho, Jinhan; Oh, Jongyeong; Kim, Dongwon; Cho, Junghyun; Kim, Sanghyun; Lee, Sangyun; Lee, Jihyun

    2015-10-01

    To investigate whether reduced radiation dose abdominal CT images reconstructed with adaptive statistical iterative reconstruction V (ASIR-V) compromise the depiction of clinically competent features when compared with the currently used routine radiation dose CT images reconstructed with ASIR. 27 consecutive patients (mean body mass index: 23.55 kg m(-2) underwent CT of the abdomen at two time points. At the first time point, abdominal CT was scanned at 21.45 noise index levels of automatic current modulation at 120 kV. Images were reconstructed with 40% ASIR, the routine protocol of Dong-A University Hospital. At the second time point, follow-up scans were performed at 30 noise index levels. Images were reconstructed with filtered back projection (FBP), 40% ASIR, 30% ASIR-V, 50% ASIR-V and 70% ASIR-V for the reduced radiation dose. Both quantitative and qualitative analyses of image quality were conducted. The CT dose index was also recorded. At the follow-up study, the mean dose reduction relative to the currently used common radiation dose was 35.37% (range: 19-49%). The overall subjective image quality and diagnostic acceptability of the 50% ASIR-V scores at the reduced radiation dose were nearly identical to those recorded when using the initial routine-dose CT with 40% ASIR. Subjective ratings of the qualitative analysis revealed that of all reduced radiation dose CT series reconstructed, 30% ASIR-V and 50% ASIR-V were associated with higher image quality with lower noise and artefacts as well as good sharpness when compared with 40% ASIR and FBP. However, the sharpness score at 70% ASIR-V was considered to be worse than that at 40% ASIR. Objective image noise for 50% ASIR-V was 34.24% and 46.34% which was lower than 40% ASIR and FBP. Abdominal CT images reconstructed with ASIR-V facilitate radiation dose reductions of to 35% when compared with the ASIR. This study represents the first clinical research experiment to use ASIR-V, the newest version of

  11. Classification of radar clutter using neural networks.

    Science.gov (United States)

    Haykin, S; Deng, C

    1991-01-01

    A classifier that incorporates both preprocessing and postprocessing procedures as well as a multilayer feedforward network (based on the back-propagation algorithm) in its design to distinguish between several major classes of radar returns including weather, birds, and aircraft is described. The classifier achieves an average classification accuracy of 89% on generalization for data collected during a single scan of the radar antenna. The procedures of feature selection for neural network training, the classifier design considerations, the learning algorithm development, the implementation, and the experimental results of the neural clutter classifier, which is simulated on a Warp systolic computer, are discussed. A comparative evaluation of the multilayer neural network with a traditional Bayes classifier is presented.

  12. Clutter in the GMTI range-velocity map.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin Walter

    2009-04-01

    Ground Moving Target Indicator (GMTI) radar maps echo data to range and range-rate, which is a function of a moving target's velocity and its position within the antenna beam footprint. Even stationary clutter will exhibit an apparent motion spectrum and can interfere with moving vehicle detections. Consequently it is very important for a radar to understand how stationary clutter maps into radar measurements of range and velocity. This mapping depends on a wide variety of factors, including details of the radar motion, orientation, and the 3-D topography of the clutter.

  13. Maximum Likelihood Joint Tracking and Association in Strong Clutter

    Directory of Open Access Journals (Sweden)

    Leonid I. Perlovsky

    2013-01-01

    Full Text Available We have developed a maximum likelihood formulation for a joint detection, tracking and association problem. An efficient non-combinatorial algorithm for this problem is developed in case of strong clutter for radar data. By using an iterative procedure of the dynamic logic process “from vague-to-crisp” explained in the paper, the new tracker overcomes the combinatorial complexity of tracking in highly-cluttered scenarios and results in an orders-of-magnitude improvement in signal-to-clutter ratio.

  14. Maximum Likelihood Joint Tracking and Association in Strong Clutter

    Directory of Open Access Journals (Sweden)

    Leonid I. Perlovsky

    2013-01-01

    Full Text Available We have developed a maximum likelihood formulation for a joint detection, tracking and association problem. An efficient non‐combinatorial algorithm for this problem is developed in case of strong clutter for radar data. By using an iterative procedure of the dynamic logic process “from vague‐to‐crisp” explained in the paper, the new tracker overcomes the combinatorial complexity of tracking in highly‐cluttered scenarios and results in an orders‐of‐magnitude improvement in signal‐ to‐clutter ratio.

  15. Gaussian Mixture Reduction for Bayesian Target Tracking in Clutter

    Science.gov (United States)

    2005-12-22

    IEEE Transactions on Automatic Control, AC-17(4):439–448, August 1972. 3. Arfken , George B. and Hans J. Weber. Mathematical Methods for Physicists...developed this method in a more formal mathematical manner. As their work popu- larized the method of maximum likelihood, it became commonly known as...Brooks/Cole Publish- ing Company, Belmont, CA, 1990. 10. Cramér, Harald. Mathematical Methods of Statistics. Princeton University Press, Princeton

  16. Contrast agent and radiation dose reduction in abdominal CT by a combination of low tube voltage and advanced image reconstruction algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Buls, Nico; Gompel, Gert van; Nieboer, Koenraad; Willekens, Inneke; Mey, Johan de [Universitair Ziekenhuis Brussel (UZ Brussel), Department of Radiology, Brussels (Belgium); Vrije Universiteit Brussel (VUB), Research group LABO, Brussel (Belgium); Cauteren, Toon van [Vrije Universiteit Brussel (VUB), Research group LABO, Brussel (Belgium); Verfaillie, Guy [Universitair Ziekenhuis Brussel (UZ Brussel), Department of Radiology, Brussels (Belgium); Evans, Paul; Macholl, Sven; Newton, Ben [GE Healthcare, Department of Medical Diagnostics, Amersham, Buckinghamshire (United Kingdom)

    2015-04-01

    To assess image quality in abdominal CT at low tube voltage combined with two types of iterative reconstruction (IR) at four reduced contrast agent dose levels. Minipigs were scanned with standard 320 mg I/mL contrast concentration at 120 kVp, and with reduced formulations of 120, 170, 220 and 270 mg I/mL at 80 kVp with IR. Image quality was assessed by CT value, dose normalized contrast and signal to noise ratio (CNRD and SNRD) in the arterial and venous phases. Qualitative analysis was included by expert reading. Protocols with 170 mg I/mL or higher showed equal or superior CT values: aorta (278-468 HU versus 314 HU); portal vein (205-273 HU versus 208 HU); liver parenchyma (122-146 HU versus 115 HU). In the aorta, all 170 mg I/mL protocols or higher yielded equal or superior CNRD (15.0-28.0 versus 13.7). In liver parenchyma, all study protocols resulted in higher SNRDs. Radiation dose could be reduced from standard CTDI{sub vol} = 7.8 mGy (6.2 mSv) to 7.6 mGy (5.2 mSv) with 170 mg I/mL. Combining 80 kVp with IR allows at least a 47 % contrast agent dose reduction and 16 % radiation dose reduction for images of comparable quality. (orig.)

  17. Comparison of intragastric balloon therapy and intensive lifestyle modification therapy with respect to weight reduction and abdominal fat distribution in super-obese Japanese patients.

    Science.gov (United States)

    Takihata, Masahiro; Nakamura, Akinobu; Aoki, Kazutaka; Kimura, Mari; Sekino, Yusuke; Inamori, Masahiko; Maeda, Shin; Gotoh, Eiji; Nakajima, Atsushi; Terauchi, Yasuo

    2014-01-01

    This study compared the impacts of intragastric balloon (IGB) therapy and intensive lifestyle modification therapy on abdominal fat distribution. Sixteen extremely obese Japanese patients were assigned to an intensive lifestyle modification therapy group with educational hospitalisation (8 patients) or an IGB therapy group (8 patients) and were followed up for 6 months. The main outcome measures were the differences at 6 months, relative to the baseline values, in the visceral fat area (VFA), subcutaneous fat area (SFA), and liver volume as measured using computed tomography. At 0 month, the body weights (BWs) were 121.3±19.0 kg and 127.1±24.4 kg and the VFAs were 299±55 cm2 and 257±56 cm2 in the intensive lifestyle modification therapy group and the IGB therapy group, respectively. No statistically significant differences in the baseline characteristics were observed between these two groups. At 6 months, no difference in the changes in BW from the baseline value (-11.5 [-16.4, -6.6] kg vs. -11.2 [-18.9, -3.4] kg) was seen between the two groups. However, a statistically significant difference in the change in the VFA (-66 [-87, -44] cm2 vs. -22 [-70, 26]cm(2) [P=0.027]) was observed; no significant changes in the SFA or liver volume were seen. In conclusion, IGB therapy was as effective as intensive lifestyle modification therapy for weight reduction but was less effective with respect to the improvement in abdominal visceral fat accumulation and liver steatosis in super-obese Japanese patients.

  18. Dose reduction in abdominal computed tomography: intraindividual comparison of image quality of full-dose standard and half-dose iterative reconstructions with dual-source computed tomography.

    Science.gov (United States)

    May, Matthias S; Wüst, Wolfgang; Brand, Michael; Stahl, Christian; Allmendinger, Thomas; Schmidt, Bernhard; Uder, Michael; Lell, Michael M

    2011-07-01

    We sought to evaluate the image quality of iterative reconstruction in image space (IRIS) in half-dose (HD) datasets compared with full-dose (FD) and HD filtered back projection (FBP) reconstruction in abdominal computed tomography (CT). To acquire data with FD and HD simultaneously, contrast-enhanced abdominal CT was performed with a dual-source CT system, both tubes operating at 120 kV, 100 ref.mAs, and pitch 0.8. Three different image datasets were reconstructed from the raw data: Standard FD images applying FBP which served as reference, HD images applying FBP and HD images applying IRIS. For the HD data sets, only data from 1 tube detector-system was used. Quantitative image quality analysis was performed by measuring image noise in tissue and air. Qualitative image quality was evaluated according to the European Guidelines on Quality criteria for CT. Additional assessment of artifacts, lesion conspicuity, and edge sharpness was performed. : Image noise in soft tissue was substantially decreased in HD-IRIS (-3.4 HU, -22%) and increased in HD-FBP (+6.2 HU, +39%) images when compared with the reference (mean noise, 15.9 HU). No significant differences between the FD-FBP and HD-IRIS images were found for the visually sharp anatomic reproduction, overall diagnostic acceptability (P = 0.923), lesion conspicuity (P = 0.592), and edge sharpness (P = 0.589), while HD-FBP was rated inferior. Streak artifacts and beam hardening was significantly more prominent in HD-FBP while HD-IRIS images exhibited a slightly different noise pattern. Direct intrapatient comparison of standard FD body protocols and HD-IRIS reconstruction suggest that the latest iterative reconstruction algorithms allow for approximately 50% dose reduction without deterioration of the high image quality necessary for confident diagnosis.

  19. Performance of adaptive iterative dose reduction 3D integrated with automatic tube current modulation in radiation dose and image noise reduction compared with filtered-back projection for 80-kVp abdominal CT: Anthropomorphic phantom and patient study.

    Science.gov (United States)

    Chen, Chien-Ming; Lin, Yang-Yu; Hsu, Ming-Yi; Hung, Chien-Fu; Liao, Ying-Lan; Tsai, Hui-Yu

    2016-09-01

    Evaluate the performance of Adaptive Iterative Dose Reduction 3D (AIDR 3D) and compare with filtered-back projection (FBP) regarding radiation dosage and image quality for an 80-kVp abdominal CT. An abdominal phantom underwent four CT acquisitions and reconstruction algorithms (FBP; AIDR 3D mild, standard and strong). Sixty-three patients underwent unenhanced liver CT with FBP and standard level AIDR 3D. Further post-acquisition reconstruction with strong level AIDR 3D was made. Patients were divided into two groups (radiation dose by 72% in the phantom and 47.1% in the patient study compared with FBP. There was no difference in mean attenuations. Image noise was the lowest and signal-to-noise ratio the highest using strong level AIDR 3D in both patient groups. For Deffradiation dose and maintenance of image quality compared with FBP. Using AIDR 3D reconstruction, patients with larger abdomen circumference could be imaged at 80kVp. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  20. Desk Congest Desktop Congesting Software for Desktop Clutter Congestion

    Directory of Open Access Journals (Sweden)

    Solomon A. Adepoju

    2015-06-01

    Full Text Available Abstract The computer desktop environment is a working environment which can be likened unto a users desk in homes and offices. Often times the computer desktop get cluttered with files either as shortcuts used for quick links files stored temporarily to be accessed later or just being dumped there for no vivid reasons. However previous researches have shown that cluttered desktop affects users productivity and getting these files organized is a laborious task for most users. To be able to conveniently alleviate the effect clutters have on users performances and productivity there is need for third party software that will help get the desktop environment organized in a logical and efficient manner. It is to this end that desktop decongesting software is being designed and implemented to help curb clutter problems which existing tools have only partially addressed. The system is designed using Visual Basic .Net and it proves to be effective in tackling desktop congestion problem.

  1. Arta process model of maritime clutter and targets

    CSIR Research Space (South Africa)

    McDonald

    2012-10-01

    Full Text Available A coherent autoregressive–to–anything (ARTA) stationary stochastic process for modelling maritime clutter and targets is presented in this paper. The ARTA stochastic process model is an improvement over previous models in the sense...

  2. Limits to Clutter Cancellation in Multi-Aperture GMTI Data

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bickel, Douglas L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-03-01

    Multi-aperture or multi-subaperture antennas are fundamental to Ground Moving Target Indicator (GMTI) radar systems in order to detect slow-moving targets with Doppler characteristics similar to clutter. Herein we examine the performance of several subaperture architectures for their clutter cancelling performance. Significantly, more antenna phase centers isn’t always better, and in fact is sometimes worse, for detecting targets.

  3. Statistical model of clutter suppression in tissue harmonic imaging

    Science.gov (United States)

    Yan, Xiang; Hamilton, Mark F.

    2011-01-01

    A statistical model is developed for the suppression of clutter in tissue harmonic imaging (THI). Tissue heterogeneity is modeled as a random phase screen that is characterized by its correlation length and variance. With the autocorrelation function taken to be Gaussian and for small variance, statistical solutions are derived for the mean intensities at the fundamental and second-harmonic frequencies in the field of a focused sound beam that propagates through the phase screen. The statistical solutions are verified by comparison with ensemble averaging of direct numerical simulations. The model demonstrates that THI reduces the aberration clutter appearing in the focal region regardless of the depth of the aberrating layer, with suppression of the clutter most effective when the layer is close to the source. The model is also applied to the reverberation clutter that is transmitted forward along the axis of the beam. As with aberration clutter, suppression of such reverberation clutter by THI is most pronounced when the tissue heterogeneity is located close to the source. PMID:21428483

  4. Space-time clutter model for airborne bistatic radar with non-Gaussian statistics

    Institute of Scientific and Technical Information of China (English)

    Duan Rui; Wang Xuegang; Yiang Chaoshu; Chen Zhuming

    2009-01-01

    To validate the potential space-time adaptive processing (STAP) algorithms for airborne bistatic radar clutter suppression under nonstationary and non-Gaussian clutter environments, a statistically non-Gaussian, space-time clutter model in varying bistatic geometrical scenarios is presented. The inclusive effects of the model contain the range dependency of bistatic clutter spectrum and clutter power variation in range-angle cells. To capture them, a new approach to coordinate system conversion is initiated into formulating bistatic geometrical model, and the bistatic non-Gaussian amplitude clutter representation method based on a compound model is introduced. The veracity of the geometrical model is validated by using the bistatie configuration parameters of multi-channel airborne radar measurement (MCARM) experiment. And simulation results manifest that the proposed model can accurately shape the space-time clutter spectrum tied up with specific airborne bistatic radar scenario and can characterize the heterogeneity of clutter amplitude distribution in practical clutter environments.

  5. Study on Clutter Model and Characteristics of Airborne Radar with Parabolic Conformal Phased Array

    Institute of Scientific and Technical Information of China (English)

    Hao Jiang; Nini Rao; Xingbo Chen; Jiabin Zhou; Chaoyang Qiu; Wen Zhai; Zhimei Hao

    2016-01-01

    The studies on clutter modeling and suppression of airborne radar with a parabolic conformal array are uncommon due to the complexity of this type of antenna array configuration. The correct understanding of clutter characteristics for airborne radar with a parabolic conformal antenna array is the prerequisite and foundation of optimal suppression of this type of clutter. This paper establishes the model of clutter echo of airborne parabolic conformal phased array radar and analyzes the structure characteristics and the distribution features of this type of clutter. The simulation results show that this type of clutter has the following characteristics: 1) The main lobe on the azimuth is seriously broadened, 2) the power spectrum presents strong heterogeneity, and 3) the freedom degrees are high. Based on the existing related clutter suppression methods, we verified the correctness of the constructed clutter model. This work has an important guidance to further study on clutter suppression methods in airborne parabolic conformal array radar.

  6. LANE MARKING DETECTION IN CLUTTERED ENVIRONMENT

    Institute of Scientific and Technical Information of China (English)

    李青; 郑南宁; 程洪

    2003-01-01

    Objective To determine the positions of marking in the presence of distracting shadows, highlight, pavement cracks, etc. Methods RGB color space is transformed into I1I2I3 color space and I2 component was used to form a new image with less effect of the clutter. Using an improved edge detection operator, an edge strength map was produced, and binarilized by adaptive thresholds. The binary image was labeled and circularity of all connected components is calculated. The Self-Organizing Mapping is adopted to extract regions which imply potential marking. Finally the position of marking was obtained by curve fitting. Results Color information was utilized fully, all thresholds were set adaptively and lane marking could be detected in challenging images with shadows, highlight or other cars. Conclusion The method based on circularity of connected components shows its outstanding robustness to lane marking detection and has a wide variety of applications in the areas of vehicle autonomous navigation and driver assistance system.

  7. Dose reduction to the pediatric and adult as a result of spectral optimization for high-contrast abdominal CT: A phantom study

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Pih Hyun; Lee, Chang Lae; Kim, Dae Hong; Kim, Hee Joung [Dept. of Radiological Science and Research Institute of Health Science, Yonsei University (Korea, Republic of)

    2012-04-15

    Improvement in multi-detector row CT (MDCT) technology now allows numerous acquisitions to be easily and rapidly performed, leading to a possibly marked increase of the dose to patients. Managing patient dose is therefore a major concern in pediatric MDCT. Dose optimization consists of obtaining the lowest acceptable image quality compatible with diagnostic purposes. It is still the radiologist's responsibility to set the appropriate CT parameters (i.e., tube potential, beam collimation, tube current-time product or AEC-quality indices) to keep the dose 'as low as reasonably achievable' for diagnostic purposes. However, while radiation dose may be precisely defined by dedicated quantities such as the CT dose index (CTDI), image quality is still difficult to objectively assess. Up until now, the 'appropriate' quality ratio was mostly defined on the basis of empirical methods. The purpose of the present study was to assess and compare various physically measurable image quality indices obtained with dedicated pediatric phantoms and CT protocols in order to more clearly understand which index should preferably be used in children to manage the dose for routine abdominal MDCT protocols, and to provide guidance on dose reduction on the basis of patient dimensions.

  8. A new poly(1,3-trimethylene carbonate) film provides effective adhesion reduction after major abdominal surgery in a rat model

    NARCIS (Netherlands)

    Vogels, Ruben R.M.; Bosmans, Joanna W.A.M.; van Barneveld, Kevin W.Y.; Verdoold, Vincent; van Rijn, Selwyn; Gijbels, Marion J.J.; Penders, John; Breukink, Stephanie; Grijpma, Dirk W.; Bouvy, Nicole D.

    2015-01-01

    Background Postoperative adhesions remain a major clinical problem after abdominal surgery. We evaluated the efficacy of a new poly(trimethylene carbonate) (PTMC) film as an antiadhesive material. In many abdominal operations, there is an increased risk of fecal contamination; the risk of (increased

  9. A new poly(1,3-trimethylene carbonate) film provides effective adhesion reduction after major abdominal surgery in a rat model

    NARCIS (Netherlands)

    Vogels, Ruben R. M.; Bosmans, Joanna W. A. M.; van Barneveld, Kevin W. Y.; Verdoold, Vincent; van Rijn, Selwyn; Gijbels, Marion J. J.; Penders, John; Breukink, Stephanie O.; Grijpma, Dirk W.; Bouvy, Nicole D.

    2015-01-01

    Background. Postoperative adhesions remain a major clinical problem after abdominal surgery. We evaluated the efficacy of a new poly(trimethylene carbonate) (PTMC) film as an antiadhesive material. In many abdominal operations, there is an increased risk of fecal contamination; the risk of (increase

  10. Abdominal pain

    Science.gov (United States)

    Stomach pain; Pain - abdomen; Belly ache; Abdominal cramps; Bellyache; Stomachache ... Almost everyone has pain in the abdomen at some point. Most of the time, it is not serious. How bad your pain is does not always reflect the seriousness ...

  11. Abdominal actinomycosis.

    Science.gov (United States)

    Wagenlehner, F M E; Mohren, B; Naber, K G; Männl, H F K

    2003-08-01

    Intra-abdominal and extraperitoneal actinomycosis are rare infections, caused by different Actinomyces species. However, they have been diagnosed more frequently in the last ten years. We report three cases of abdominal actinomycosis and a literature review of the last eight years. All three patients were diagnosed by means of histopathologic examination only. In one case, an intrauterine device (IUD) was associated with the infection. Therapy consisted of surgical resection of the inflammatory, infected tissue, and long-term antibiotic therapy. All patients are free of recurrence. Abdominal actinomycosis should be included in the differential diagnosis of an abdominal pathology of insidious onset, especially when an IUD is in place. Even when infection had spread extensively, combined operative and antibiotic therapy cured most of the cases.

  12. Ultrawideband radar clutter measurements of forested terrain, 1991--1992

    Energy Technology Data Exchange (ETDEWEB)

    Sheen, D.M.; Severtsen, R.H.; Prince, J.M.; Davis, K.C.; Collins, H.D.

    1993-06-01

    The ultrawideband (UWB) radar clutter measurements project was conducted to provide radar clutter data for new ultrawideband radar systems which are currently under development. A particular goal of this project is to determine if conventional narrow band clutter data may be extrapolated to the UWB case. This report documents measurements conducted in 1991 and additional measurements conducted in 1992. The original project consisted of clutter measurements of forested terrain in the Olympic National Forest near Sequim, WA. The impulse radar system used a 30 kW peak impulse source with a 2 Gigasample/second digitizer to form a UHF (300--1000 MHz) ultrawideband impulse radar system. Additional measurements were conducted in parallel using a Systems Planning Corporation (SPC) step-chirp radar system. This system utilized pulse widths of 1330 nanoseconds over a bandwidth of 300--1000 MHz to obtain similar resolution to the impulse system. Due to the slow digitizer data throughput in the impulse radar system, data collection rates were significantly higher using the step-chirp system. Additional forest clutter measurements were undertaken in 1992 to increase the amount of data available, and especially to increase the amount of data from the impulse radar system.

  13. Global Infrasound Association Based on Probabilistic Clutter Categorization

    Science.gov (United States)

    Arora, Nimar; Mialle, Pierrick

    2016-04-01

    The IDC advances its methods and continuously improves its automatic system for the infrasound technology. The IDC focuses on enhancing the automatic system for the identification of valid signals and the optimization of the network detection threshold by identifying ways to refine signal characterization methodology and association criteria. An objective of this study is to reduce the number of associated infrasound arrivals that are rejected from the automatic bulletins when generating the reviewed event bulletins. Indeed, a considerable number of signal detections are due to local clutter sources such as microbaroms, waterfalls, dams, gas flares, surf (ocean breaking waves) etc. These sources are either too diffuse or too local to form events. Worse still, the repetitive nature of this clutter leads to a large number of false event hypotheses due to the random matching of clutter at multiple stations. Previous studies, for example [1], have worked on categorization of clutter using long term trends on detection azimuth, frequency, and amplitude at each station. In this work we continue the same line of reasoning to build a probabilistic model of clutter that is used as part of NETVISA [2], a Bayesian approach to network processing. The resulting model is a fusion of seismic, hydroacoustic and infrasound processing built on a unified probabilistic framework. References: [1] Infrasound categorization Towards a statistics based approach. J. Vergoz, P. Gaillard, A. Le Pichon, N. Brachet, and L. Ceranna. ITW 2011 [2] NETVISA: Network Processing Vertically Integrated Seismic Analysis. N. S. Arora, S. Russell, and E. Sudderth. BSSA 2013

  14. Reflectivity Model of Low Grazing Angle Radar Sea Clutter

    Institute of Scientific and Technical Information of China (English)

    FENG Sheng; CHEN Jie; CAI Tao; TU Xu-yan

    2005-01-01

    The commonly used reflectivity models of radar sea clutter are summarized. Among these models, the adjusted Barton model and the adjusted Morchin model are compared. From the analysis result, the γ-p reflectivity model is presented for low grazing angle radar sea clutter by the adjustment of the original Barton reflectivity model. The model takes into account radar frequency, grazing angle, sea condition, and polarization property. The influences of these factors on the proposed model are analyzed. The model absorbs the merits from commonly used reflectivity models for sea clutter. It introduces several researchers' opinions, and extends them. And it accounts for the reflectivity at arbitrary radar frequency from VHF to X-band, arbitrary low grazing angle, arbitrary sea condition and different polarization property. One of the main results is the proposed γ-p reflectivity model can reflect the influence of polarization on sea clutter reflectivity to some extent. The proposed γ-p reflectivity model of low-angle radar-sea clutter is validated by comparing the simulated and statistically experimental data.

  15. Ultrawideband radar clutter measurements of forested terrain, 1991--1992

    Energy Technology Data Exchange (ETDEWEB)

    Sheen, D.M.; Severtsen, R.H.; Prince, J.M.; Davis, K.C.; Collins, H.D.

    1993-06-01

    The ultrawideband (UWB) radar clutter measurements project was conducted to provide radar clutter data for new ultrawideband radar systems which are currently under development. A particular goal of this project is to determine if conventional narrow band clutter data may be extrapolated to the UWB case. This report documents measurements conducted in 1991 and additional measurements conducted in 1992. The original project consisted of clutter measurements of forested terrain in the Olympic National Forest near Sequim, WA. The impulse radar system used a 30 kW peak impulse source with a 2 Gigasample/second digitizer to form a UHF (300--1000 MHz) ultrawideband impulse radar system. Additional measurements were conducted in parallel using a Systems Planning Corporation (SPC) step-chirp radar system. This system utilized pulse widths of 1330 nanoseconds over a bandwidth of 300--1000 MHz to obtain similar resolution to the impulse system. Due to the slow digitizer data throughput in the impulse radar system, data collection rates were significantly higher using the step-chirp system. Additional forest clutter measurements were undertaken in 1992 to increase the amount of data available, and especially to increase the amount of data from the impulse radar system.

  16. Waveform design for cognitive radar: target detection in heavy clutter

    Science.gov (United States)

    Kirk, Benjamin H.; Narayanan, Ram M.; Martone, Anthony F.; Sherbondy, Kelly D.

    2016-05-01

    In many applications of radar systems, detection of targets in environments with heavy clutter and interference can be difficult. It is desired that a radar system should detect targets at a further range as well as be able to detect these targets with very few false positive or negative readings. In a cognitive radar system, there are ways that these negative effects can be mitigated and target detection can be significantly improved. An important metric to focus on for increasing target detectability is the signal-to-clutter ratio (SCR). Cognitive radar offers solutions to issues such as this with the use of a priori knowledge of targets and environments as well as real time adaptations. A feature of cognitive radar that is of interest is the ability to adapt and optimize transmitted waveforms to a given situation. A database is used to hold a priori and dynamic knowledge of the operational environment and targets to be detected, such as clutter characteristics and target radar cross-section (RCS) estimations. Assuming this knowledge is available or can be estimated in real-time, the transmitted waveform can be tailored using methods such as transmission of a spectrum corresponding to the target-to-clutter ratio (TCR). These methods provide significant improvement in distinguishing targets from clutter or interference.

  17. Public attitudes toward-and identification of-cluttering and stuttering in Norway and Puerto Rico.

    Science.gov (United States)

    St Louis, Kenneth O; Sønsterud, Hilda; Carlo, Edna J; Heitmann, Ragnhild R; Kvenseth, Helene

    2014-12-01

    The study sought to compare public attitudes toward cluttering versus stuttering in Norway and Puerto Rico and to compare respondents' identification of persons known with these fluency disorders. After reading lay definitions of cluttering and stuttering, three samples of adults from Norway and three from Puerto Rico rated their attitudes toward cluttering and/or stuttering on modified versions of the POSHA-Cl (for cluttering) and POSHA-S (for stuttering). They also identified children and adults whom they knew who either or both manifested cluttering or stuttering. Attitudes toward cluttering were essentially unaffected by rating either cluttering only or combined cluttering and stuttering on the same questionnaire in both countries. The same was also true of stuttering. Attitudes were very similar toward both disorders although slightly less positive for cluttering. Norwegian attitudes toward both disorders were generally more positive than Puerto Rican attitudes. The average respondent identified slightly more than one fluency disorder, a higher percentage for stuttering than cluttering and higher for adults than children. Cluttering-stuttering was rarely identified. Given a lay definition, this study confirmed that adults from diverse cultures hold attitudes toward cluttering that are similar to-but somewhat less positive than-their attitudes toward stuttering. It also confirmed that adults can identify cluttering among people they know, although less commonly than stuttering. Design controls in this study assured that consideration of stuttering did not affect either the attitudes or identification results for cluttering. The reader will be able to: (a) describe the effects-or lack thereof-of considerations of stuttering on attitudes toward cluttering; (b) describe differences in public identification of children and adults who either clutter or stutter; (c) describe differences between attitudes toward cluttering and stuttering in Norway and Puerto Rico

  18. Knowledge-based adaptive polarimetric detection in heterogeneous clutter

    Institute of Scientific and Technical Information of China (English)

    Yinan Zhao,Fengcong Li,; Xiaolin Qiao

    2014-01-01

    The detection performance and the constant false alarm rate behavior of the conventional adaptive detectors are severely degraded in heterogeneous clutter. This paper designs and analy-ses a knowledge-based (KB) adaptive polarimetric detector in het-erogeneous clutter. The proposed detection scheme is composed of a data selector using polarization knowledge and an adaptive polarization detector using training data. A polarization data se-lector based on the maximum likelihood estimation is proposed to remove outliers from the heterogeneous training data. This selector can remove outliers effectively, thus the training data is purified for estimating the clutter covariance matrix. Consequently, the performance of the adaptive detector is improved. We assess the performance of the KB adaptive polarimetric detector and the adaptive polarimetric detector without a data selector using sim-ulated data and IPIX radar data. The results show that the KB adaptive polarization detector outperforms its non-KB counter-parts.

  19. Analysis of high resolution land clutter using an X-band radar

    CSIR Research Space (South Africa)

    Melebari, A

    2015-10-01

    Full Text Available In modern radar systems with high range resolution, the statistical properties of clutter have a significant effect on the performance of the radar. Analyzing the radar returns from various clutter terrains is essential when aiming to optimize...

  20. Identification of cluttering and stuttering by the public in four countries.

    Science.gov (United States)

    St Louis, Kenneth O; Filatova, Yulia; Coşkun, Mehmet; Topbaş, Seyhun; Ozdemır, Sertan; Georgieva, Dobrinka; McCaffrey, Elise; George, Reshella D

    2010-12-01

    The investigators sought to explore and compare the identification of cluttering vs stuttering in four different country samples. After reading lay definitions of the two fluency disorders in their own language, convenience samples of 60-90 adult respondents from Turkey, Bulgaria, Russia, and the US identified 51-119 children or adults who either cluttered, stuttered, or both. They also indicated whether or not they, themselves, cluttered or stuttered. The majority of respondents in all four samples identified at least one person who cluttered, stuttered, or cluttered and stuttered. The average respondent identified one person with a fluency disorder, most likely a stutterer, less likely a clutterer, and least likely a clutterer-stutterer. Both similarities and differences characterized those identified in the three groups, e.g., the sex ratios were not the same. As with stuttering, the public apparently is aware of cluttering individuals and can identify such persons.

  1. AN APPROACH TO SUPPRESS SHORT-RANGE CLUTTER FOR NON-SIDE LOOKING AIRBORNE RADAR

    Institute of Scientific and Technical Information of China (English)

    Li Ming; Liao Guisheng; Zhang Liang

    2011-01-01

    When the Airborne Early Warning (AEW) radar transmits medial or high Pulse Repetitive Frequency (PRF) signal,the range ambiguity occurs.The clutter of short-range clutter has serious range dependence problem for non-Side Looking Airborne Radar (non-SLAR).As a result,the clutter plus noise covariance matrix can not be estimated correctly,and the performance of clutter suppression obtained by Space-Time Adaptive Processing (STAP) degrades greatly.The uniform linear array has not elevation degrees; therefore,the short-range clutter can not be suppressed directly.A short-range clutter suppression method is proposed.The method first estimate the elevation angles of the ambiguous short-range gate,then eliminates short-range clutter by space time interpolation and adds moving target protection in the procedure.This method can suppress the short-range clutter well.Simulation results show the validity of the method.

  2. Improved covariance matrix estimation in spectrally inhomogeneous sea clutter with application to adaptive small boat detection.

    CSIR Research Space (South Africa)

    Herselman, PL

    2008-09-01

    Full Text Available Asymptotically optimal coherent detection techniques yield sub-clutter visibility in heavy-tailed sea clutter. The adaptive linear quadratic detector inherently assumes spectral homogeneity for the reference window of the covariance matrix estimator...

  3. Non-contact radiofrequency-induced reduction of subcutaneous abdominal fat correlates with initial cardiovascular autonomic balance and fat tissue hormones: safety analysis [v1; ref status: indexed, http://f1000r.es/4pj

    Directory of Open Access Journals (Sweden)

    Jiri Pumprla

    2015-02-01

    Full Text Available Background and objective: The non-invasive reduction of subcutaneous abdominal fat became popular in the last decade. Radiofrequency (RF, non-contact, selective-field device Vanquish® has been developed to selectively induce deep fat tissue heating to reduce waist circumference. Our analysis evaluates immediate and sustained effects of this treatment on cardiovascular autonomic function and on selected metabolic parameters. Study design/patients and methods: A retrospective proof-of-concept analysis of RF treatment effects was conducted in 20 individuals with metabolic syndrome, to reduce the subcutaneous abdominal fat. Four 30-minutes treatment sessions (manufacturer´s standard protocol were performed in 1-week intervals. Vital signs, ECG, lab screening, body composition, subcutaneous fat thickness and spectral analysis of heart rate variability (HRV have been examined before, after the 1st and 4th treatment, and at follow-up visits 1 month and 3 months after the treatment. Results: The RF treatment led to a significant reduction of abdominal circumference after the 4th session (p0.59, p<0.04. Conclusions: Our analysis shows that the selective-field RF treatment is safe and efficient for reduction of subcutaneous abdominal fat. While the treatment increases the immediate sympathetic response of the body to deep tissue heating, no sustained change in autonomic function could be recorded at 1 month follow-up. The observed correlation between initial VLF spectral power and waist circumference reduction at follow-up, as well as the association of initial adiponectin values and immediate autonomic response to the treatment might be instrumental for decisions on body contouring strategies.

  4. Dose reduction at abdominal CT imaging: reduced tension (kV) or reduced intensity (mAs)?; Diminuer la dose en tomodensitometrie abdominale: baisser la tension (kV) ou la charge (mAs)?

    Energy Technology Data Exchange (ETDEWEB)

    Dion, A.M.; Helie, O.; Cordoliani, Y.S. [Hopital d' Instruction des Armees du Val-de-Grace, Service d' Imagerie, 75 - Paris (France); Berger, F.; Ott, D.; Spiegel, A. [Hopital d' Instruction des Armees Begin, Service de Medecine des Collectivites et d' Etudes Statistiques, 94 - Saint-Mande (France)

    2004-04-01

    Purpose. To compare low-dose protocols using either reduction of the tension (kV) or reduction of the intensity (mAs) at abdominal CT imaging, with reference to image quality. Materials and Methods. Fifty adult patients, weighing less than 55 kg, were prospectively included among patients referred for abdominal CT examination when the protocol required a non-contrast study. The images obtained with the standard protocol (120 kV, 200 mAs) were compared to 4 additional test images, two obtained with low intensity (120 kV, 100 mAs) and two obtained with low tension (100 kV, 200 mAs). Two senior radiologists blindly reviewed all images using both subjective (itemized list) and objective criteria (measure of standard deviation for density measurements obtained of the liver,parenchyma). Results. The image quality of the low kV protocol was better than the image quality of the low mAs protocol for both subjective and objective criteria. Conclusion. For abdominal CT imaging of standard to thin adult patients or children, dose reduction using a low kV-protocol may be an alternative to a protocol using a, low intensity. This can easily be implemented and can be used in conjunction with a dose reducing software. (author)

  5. Seascape: ray tracing synthetic marine clutter in the midwave infrared

    Science.gov (United States)

    Constantikes, Kim T.; Osmanagich, Srcan

    1996-05-01

    Seascape is a distributed application that renders synthetic images using raytracing paradigm. It incorporates a computational model of infrared marine clutter. First principle models of water waves and light transport provide a computationally intensive clutter model implemented as a raytracer. Seascape models include sea, sky, and solar radiance, reflectance, attenuating atmospheres, constructive solid geometry targets, sensor, target, and water wave dynamics, and simple sensor image formation. Our focus is on the 3 - 5 micrometers waveband but Seascape can easily be configured for operation in the visible and longwave infrared. We have implemented an efficient parallel computation of this model on a heterogeneous array of UNIX workstations.

  6. Inference-Based Surface Reconstruction of Cluttered Environments

    KAUST Repository

    Biggers, K.

    2012-08-01

    We present an inference-based surface reconstruction algorithm that is capable of identifying objects of interest among a cluttered scene, and reconstructing solid model representations even in the presence of occluded surfaces. Our proposed approach incorporates a predictive modeling framework that uses a set of user-provided models for prior knowledge, and applies this knowledge to the iterative identification and construction process. Our approach uses a local to global construction process guided by rules for fitting high-quality surface patches obtained from these prior models. We demonstrate the application of this algorithm on several example data sets containing heavy clutter and occlusion. © 2012 IEEE.

  7. Abdominal Sepsis.

    Science.gov (United States)

    De Waele, Jan J

    2016-08-01

    Abdominal infections are an important challenge for the intensive care physician. In an era of increasing antimicrobial resistance, selecting the appropriate regimen is important and, with new drugs coming to the market, correct use is important more than ever before and abdominal infections are an excellent target for antimicrobial stewardship programs. Biomarkers may be helpful, but their exact role in managing abdominal infections remains incompletely understood. Source control also remains an ongoing conundrum, and evidence is increasing that its importance supersedes the impact of antibiotic therapy. New strategies such as open abdomen management may offer added benefit in severely ill patients, but more data are needed to identify its exact role. The role of fungi and the need for antifungal coverage, on the other hand, have been investigated extensively in recent years, but at this point, it remains unclear who requires empirical as well as directed therapy.

  8. Statistical Analysis of SAR Sea Clutter for Classification Purposes

    Directory of Open Access Journals (Sweden)

    Jaime Martín-de-Nicolás

    2014-09-01

    Full Text Available Statistical analysis of radar clutter has always been one of the topics, where more effort has been put in the last few decades. These studies were usually focused on finding the statistical models that better fitted the clutter distribution; however, the goal of this work is not the modeling of the clutter, but the study of the suitability of the statistical parameters to carry out a sea state classification. In order to achieve this objective and provide some relevance to this study, an important set of maritime and coastal Synthetic Aperture Radar data is considered. Due to the nature of the acquisition of data by SAR sensors, speckle noise is inherent to these data, and a specific study of how this noise affects the clutter distribution is also performed in this work. In pursuit of a sense of wholeness, a thorough study of the most suitable statistical parameters, as well as the most adequate classifier is carried out, achieving excellent results in terms of classification success rates. These concluding results confirm that a sea state classification is not only viable, but also successful using statistical parameters different from those of the best modeling distribution and applying a speckle filter, which allows a better characterization of the parameters used to distinguish between different sea states.

  9. Clutter filter design for ultrasound color flow imaging.

    Science.gov (United States)

    Bjaerum, Steinar; Torp, Hans; Kristoffersen, Kjell

    2002-02-01

    For ultrasound color flow images with high quality, it is important to suppress the clutter signals originating from stationary and slowly moving tissue sufficiently. Without sufficient clutter rejection, low velocity blood flow cannot be measured, and estimates of higher velocities will have a large bias. The small number of samples available (8 to 16) makes clutter filtering in color flow imaging a challenging problem. In this paper, we review and analyze three classes of filters: finite impulse response (FIR), infinite impulse response (IIR), and regression filters. The quality of the filters was assessed based on the frequency response, as well as on the bias and variance of a mean blood velocity estimator using an autocorrelation technique. For FIR filters, the frequency response was improved by allowing a non-linear phase response. By estimating the mean blood flow velocity from two vectors filtered in the forward and backward direction, respectively, the standard deviation was significantly lower with a minimum phase filter than with a linear phase filter. For IIR filters applied to short signals, the transient part of the output signal is important. We analyzed zero, step, and projection initialization, and found that projection initialization gave the best filters. For regression filters, polynomial basis functions provide effective clutter suppression. The best filters from each of the three classes gave comparable bias and variance of the mean blood velocity estimates. However, polynomial regression filters and projection-initialized IIR filters had a slightly better frequency response than could be obtained with FIR filters.

  10. Clutter filtering influence on blood velocity estimation using speckle tracking.

    Science.gov (United States)

    Fadnes, Solveig; Bjærum, Steinar; Torp, Hans; Lovstakken, Lasse

    2015-12-01

    Blood speckle tracking has shown potential for solving the angle-dependency limitation in color flow imaging. However, as clutter filtering is still Doppler-based, flow velocities at near-perpendicular beam-to-flow angles can be severely attenuated. It is shown that the clutter filter also alters the speckle appearance through a decrease in the lateral imaging bandwidth, leading to poorer lateral resolution and thus tracking performance. Interestingly, at perpendicular beam-to-flow angles lateral band-pass characteristics are inferred, and the resulting lateral amplitude modulation could help improve tracking estimates. Simulations and flow phantom experiments showed that substantially improved results could be achieved by utilizing time-variant clutter filters (e.g., polynomial regression filters) despite the inherent decorrelation inferred by these filters, but only for higher ensemble sizes (N > 36). We found that, compared with color flow imaging, speckle tracking could yield consistent estimates well below the clutter filter cutoff, but with a higher variance attributed to the low signalto- noise ratio inferred by filter attenuation. Overall, provided that a low f-number and high ensemble lengths (N approx. > 36) can be used, speckle tracking can consistently provide angle- independent flow velocity estimates, limited only by a lower bound on the flow velocity itself.

  11. Reduction of abdominal fat accumulation in rats by 8-week ingestion of a newly developed sweetener made from high fructose corn syrup.

    Science.gov (United States)

    Iida, Tetsuo; Yamada, Takako; Hayashi, Noriko; Okuma, Kazuhiro; Izumori, Ken; Ishii, Reika; Matsuo, Tatsuhiro

    2013-06-01

    Many studies have shown that ingestion of high-fructose corn syrup (HFCS) may cause an increase in body weight and abdominal fat. We recently developed a new sweetener containing rare sugars (rare sugar syrup; RSS) by slight isomerization of HFCS. Here, the functional effects of RSS on body weight and abdominal fat, and biochemical parameters in Wistar rats were examined. Rats (n=30) were randomly divided into three groups and maintained for 8-weeks on starch, starch+HFCS (50:50), and starch+RSS (50:50) diets. Rats in the Starch and HFCS groups gained significantly more body weight and abdominal fat than the RSS group. Fasting serum insulin in the RSS group was significantly lower than in the Starch and HFCS groups, although serum glucose in the HFCS and RSS groups was significantly lower than that in the Starch group. Thus, the substitution of HFCS with RSS prevents obesity induced by the consumption of HFCS.

  12. Space-polarization Collaborative Suppression Method for Ionospheric Clutter in HFSWR

    Directory of Open Access Journals (Sweden)

    Yang Yunlong

    2016-12-01

    Full Text Available High Frequency Surface Wave Radar (HFSWR is able to receive surface target and low-flying aircraft echoes at a long-distance, but it suffers severely from ionospheric clutter. In this paper, a spacepolarization collaborative-based filter is introduced to mitigate ionospheric clutter. For parameter estimation on ionospheric clutter used for filters, a spatial parameter estimation algorithm based on compressive sensing is introduced to the DOA estimation of ionospheric clutter. In addition, a polarized parameter estimation algorithm based on statistical characteristics is proposed for ionospheric clutter in the range-Doppler spectrum. Higher estimation accuracy is achieved as a result of the range-Doppler spectrum; therefore, these two estimation algorithms enhance the performance of the space-polarization collaborative suppression method for ionospheric clutter. Experimental results of practical dual-polarized HFSWR data show the effectiveness of the two algorithms and the above mentioned filter for ionospheric clutter suppression.

  13. Abdominal Aortic Aneurysm (AAA)

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Abdominal Aortic Aneurysm (AAA) Abdominal aortic aneurysm (AAA) occurs when atherosclerosis ... an abdominal aortic aneurysm treated? What is an abdominal aortic aneurysm? The aorta, the largest artery in the body, ...

  14. Detecting weather radar clutter using satellite-based nowcasting products

    DEFF Research Database (Denmark)

    Jensen, Thomas B.S.; Gill, Rashpal S.; Overgaard, Søren

    2006-01-01

    for the detecting and removal of clutter. Naturally, the improved spatio-temporal resolution of the Meteosat Second Generation sensors, coupled with its increased number of spectral bands, is expected to yield even better detection accuracies. Weather radar data from three C-band Doppler weather radars...... Application Facility' of EUMETSAT and is based on multispectral images from the SEVIRI sensor of the Meteosat-8 platform. Of special interest is the 'Precipitating Clouds' product, which uses the spectral information coupled with surface temperatures from Numerical Weather Predictions to assign probabilities...... by the resolution of the radar data. Subsequently, a supervised classifier was developed based on training data selected by a weather radar expert. Results of classification of data from several different meteorological events are shown. Cases of widespread sea clutter caused by anomalous propagation are especially...

  15. Decorrelating Clutter Statistics for Long Integration Time SAR Imaging

    Science.gov (United States)

    Leanza, Antonio; Monti Guarnieri, Andrea; Recchia, Andrea; Broquetas Ibars, Antoni; Ruiz Rodon, Josep

    2015-05-01

    It is presented an experiment aimed to assess and eventually complement the Billingsley Internal Clutter Motion (ICM) model for long integration time SAR imaging. Exploiting a real-aperture rotating antenna Ground-Based RADAR, observations of rural areas in different periods of the year have been performed. The collected data, obtained from two different acquisition modes, have been processed to obtain short-term and long-term clutter de-correlation analysis. The results obtained revealed interesting aspects of the phenomenon. In particular, it can be observed that the process is non-stationary with time, say minutes to hours, and that DC/AC ratio follows a day/night characteristic. Moreover, the results showed values of the AC component decay rate β higher than the foreseen ones in the considered spectral interval, which is quite below the one analyzed in the Billingsley experiment.

  16. Bistatic MIMO Radar Clutter Suppression by Exploiting the Transmit Angle

    Directory of Open Access Journals (Sweden)

    Li Jun

    2014-04-01

    Full Text Available The transmit angle of bistatic radars can be obtained by introducing Multiple-Input Multiple-Output (MIMO radar techniques. The Three-Dimensional (3D clutter spectra, that is, the transmit angle, receive angle, and Doppler frequency, are introduced using the additional angle information to Space-Time Adaptive Processing (STAP. This study reviews the researches on bistatic MIMO-STAP. 3D space-time adaptive processing methods for airborne bistatic side-looking MIMO radars, such as 3D-LCMV, 3D-ACR, 3D-JDL, and 3D projection-based reduced dimensional STAP methods, are discussed. Simulation results show that the proposed methods can improve the small-sample support performance of range-dependent clutter suppression in bistatic side-looking MIMO radar. Finally, the results are summarized and the prospects of bistatic MIMO-STAP are discussed.

  17. Polarization Techniques for Mitigation of Low Grazing Angle Sea Clutter

    Science.gov (United States)

    2017-01-01

    introducing undue computational complexity or requiring restructuring of the chain. For CPIs comprising more than one pulse and at least 64 range...without introducing undue computational complexity or requiring restructuring of the chain. The computational complexity of PCL was derived, and proved...sea clutter. Tech- nical Report SAND2010-3828, Sandia National Laboratories. Reilly, J. and Dockery, G. (1990). Influence of evaporation ducts on

  18. Report on Scattering Physics of Multistatic Radar Sea Clutter

    Science.gov (United States)

    2014-05-30

    clutter & targets, and assessing detection schemes using the observations and the results of data analysis. The panel recognises the potential value ...similar (as they should be, since they are based on some of the same data), whilst the GIT model has much smaller values of reflectivity at low sea...When the power is summed over range, averaged over many surface realisations and recalculated at various grazing angles and rms sea surface wave

  19. A Framework for Symmetric Part Detection in Cluttered Scenes

    Directory of Open Access Journals (Sweden)

    Tom Lee

    2015-07-01

    Full Text Available The role of symmetry in computer vision has waxed and waned in importance during the evolution of the field from its earliest days. At first figuring prominently in support of bottom-up indexing, it fell out of favour as shape gave way to appearance and recognition gave way to detection. With a strong prior in the form of a target object, the role of the weaker priors offered by perceptual grouping was greatly diminished. However, as the field returns to the problem of recognition from a large database, the bottom-up recovery of the parts that make up the objects in a cluttered scene is critical for their recognition. The medial axis community has long exploited the ubiquitous regularity of symmetry as a basis for the decomposition of a closed contour into medial parts. However, today’s recognition systems are faced with cluttered scenes and the assumption that a closed contour exists, i.e., that figure-ground segmentation has been solved, rendering much of the medial axis community’s work inapplicable. In this article, we review a computational framework, previously reported in [1–3], that bridges the representation power of the medial axis and the need to recover and group an object’s parts in a cluttered scene. Our framework is rooted in the idea that a maximally-inscribed disc, the building block of a medial axis, can be modelled as a compact superpixel in the image. We evaluate the method on images of cluttered scenes.

  20. Adaptive Robust Waveform Selection for Unknown Target Detection in Clutter

    Institute of Scientific and Technical Information of China (English)

    Lu-Lu Wang; Hong-Qiang Wang; Yu-Liang Qin; Yong-Qiang Cheng

    2014-01-01

    @@@A basic assumption of most recently proposed waveform design algorithms is that the target impulse response is a known deterministic function or a stochastic process with a known power spectral density (PSD). However, it is well-known that a target impulse response is neither easily nor accurately obtained; besides it changes sharply with attitude angles. Both of the aforementioned cases complicate the waveform design process. In this paper, an adaptive robust waveform selection method for unknown target detection in clutter is proposed. The target impulse response is considered to be unknown but belongs to a known uncertainty set. An adaptive waveform library is devised by using a signal-to-clutter-plus-noise ratio (SCNR)- based optimal waveform design method. By applying the minimax robust waveform selection method, the optimal robust waveform is selected to ensure the lowest performance bound of the unknown target detection in clutter. Results show that the adaptive waveform library outperforms the predefined linear frequency modulation (LFM) waveform library on the SCNR bound.

  1. An adaptive clutter and interference suppression with a minimum residue noise power

    Science.gov (United States)

    Kwag, Young Kil

    The author presents an adaptive technique for the suppression of clutter and interference in environments where no a priori knowledge about the target or the clutter and interference statistics is available. The adaptive processor generates the average weight vector, in the sense of minimum-residue-noise power, on the basis of the injected noise-level vector in the weight control algorithm. The set of weight vectors generated in a particular range-azimuth space can be stored and switched to the same sector for the unwanted-noise rejection. The adaptation rate is significantly increased when the residue noise is removed from the combiner output. The system improvement factor in suppressing the clutter and interference is not sensitive to the strength of the input CSR (clutter suppression rate) and is largely dependent on the residue clutter and interference. Simulation results show the effectiveness of the proposed method in improving the clutter and interference rejection capability.

  2. Abdominal Compartment Syndrome due to OHSS

    Directory of Open Access Journals (Sweden)

    Firoozeh Veisi

    2012-03-01

    Full Text Available Abdominal compartment syndrome is a dangerous clinical situation, usually following abdominal injuries&operations. It is seldom observed in patients with gynecologic and obstetric problems. Abdominalcompartment syndrome may be consequence ovarian hyperstimulation syndrome. A 28-year-old womanpresented as a sever ovarian hyperstimulation.The increased IAP indicated that OHSS may beconsidered a compartment syndrome. Abdominal compartment syndrome needs laparotomy orparacentesis for reduction of pressure.

  3. ABDOPRE: dispositivo de aplicação externa para redução da pressão intra-abdominal: Experiencia clínica preliminar ABDOPRE: dispositivo de aplicación externa para reducción de presión intraabdominal: Preliminary clinical experience ABDOPRE: an external device for the reduction of intra-abdominal pressure

    Directory of Open Access Journals (Sweden)

    Francisco Pracca

    2011-06-01

    Full Text Available São descritos os objetivos de redução da pressão intra-abdominal e o projeto de um dispositivo que os atenda. O ABDO-PRE compreende, pela primeira vez, um mecanismo de servo-controle de aplicação externa que mede a pressão intravesical como variável de controle. São apresentados os resultados da aplicação em 4 pacientes com hipertensão intra-abdominal, produzindo uma redução de 16% a 35% em três casos e um aumento paradoxal da pressão em um dos casos, devido a um desajuste entre a geometria da câmara de vácuo e a alteração anatômica acarretada pela obesidade da paciente. Estes resultados são promissores em relação ao possível uso do ABDOPRE na prática clínica para redução da hipertensão intra-abdominal.Se describen los objetivos de reducción de la presión intraabdominal y el proyecto de un dispositivo que los cumpla. ABDOPRE comprende por primera vez un mecanismo servcocontrolado de aplicación externa que toma la presión intravesical como variable de control. Se presenta el resultado de la aplicación en 4 pacientes afectados por hipertensión intraabdominal, con el resultado de una reducción de entre 16% y 35% en tres casos y de un aumento paradojal de presión en un caso debido a desajuste de la geometría de la campana de vacío a la anatomía obesa del paciente. Estos resultados prometen el posible uso de ABDOPRE para la reducción de la hipertensión intraabdominal en la práctica clínica.This article describes a device for the reduction of intra-abdominal pressure. The device (ABDOPRE includes a unique external servo-control mechanism, based on urinary bladder pressure measurement. The results of ABDOPRE use in the first four intra-abdominal hypertension patients are reported; the device resulted in a reduction of intra-abdominal pressure between 16% and 35% in 3 cases and in a paradoxical increase of the intra-abdominal pressure in an obese woman, likely due to inappropriate chamber size for the patient

  4. Removing interfering clutter associated with radar pulses that an airborne radar receives from a radar transponder

    Science.gov (United States)

    Ormesher, Richard C.; Axline, Robert M.

    2008-12-02

    Interfering clutter in radar pulses received by an airborne radar system from a radar transponder can be suppressed by developing a representation of the incoming echo-voltage time-series that permits the clutter associated with predetermined parts of the time-series to be estimated. These estimates can be used to estimate and suppress the clutter associated with other parts of the time-series.

  5. An Airborne Radar Clutter Tracking Algorithm Based on Multifractal and Fuzzy C-Mean Cluster

    Institute of Scientific and Technical Information of China (English)

    Wei Zhang; Sheng-Lin Yu; Gong Zhang

    2007-01-01

    For an airborne lookdown radar, clutter power often changes dynamically about 80 dB with wide distributions as the platform moves. Therefore, clutter tracking techniques are required to guide the selection of const false alarm rate (CFAR) schemes. In this work, clutter tracking is done in image domain and an algorithm combining multifractal and fuzzy C-mean (FCM) cluster is proposed. The clutter with large dynamic distributions in power density is converted to steady distributions of multifractal exponents by the multifractal transformation with the optimum moment. Then, later, the main lobe and side lobe are tracked from the multifractal exponents by FCM clustering method.

  6. Clutter in electronic medical records: examining its performance and attentional costs using eye tracking.

    Science.gov (United States)

    Moacdieh, Nadine; Sarter, Nadine

    2015-06-01

    The objective was to use eye tracking to trace the underlying changes in attention allocation associated with the performance effects of clutter, stress, and task difficulty in visual search and noticing tasks. Clutter can degrade performance in complex domains, yet more needs to be known about the associated changes in attention allocation, particularly in the presence of stress and for different tasks. Frequently used and relatively simple eye tracking metrics do not effectively capture the various effects of clutter, which is critical for comprehensively analyzing clutter and developing targeted, real-time countermeasures. Electronic medical records (EMRs) were chosen as the application domain for this research. Clutter, stress, and task difficulty were manipulated, and physicians' performance on search and noticing tasks was recorded. Several eye tracking metrics were used to trace attention allocation throughout those tasks, and subjective data were gathered via a debriefing questionnaire. Clutter degraded performance in terms of response time and noticing accuracy. These decrements were largely accentuated by high stress and task difficulty. Eye tracking revealed the underlying attentional mechanisms, and several display-independent metrics were shown to be significant indicators of the effects of clutter. Eye tracking provides a promising means to understand in detail (offline) and prevent (in real time) major performance breakdowns due to clutter. Display designers need to be aware of the risks of clutter in EMRs and other complex displays and can use the identified eye tracking metrics to evaluate and/or adjust their display. © 2015, Human Factors and Ergonomics Society.

  7. Ultra-low dose abdominal MDCT: Using a knowledge-based Iterative Model Reconstruction technique for substantial dose reduction in a prospective clinical study

    Energy Technology Data Exchange (ETDEWEB)

    Khawaja, Ranish Deedar Ali, E-mail: rkhawaja@mgh.harvard.edu [MGH Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Singh, Sarabjeet; Blake, Michael; Harisinghani, Mukesh; Choy, Gary; Karosmangulu, Ali; Padole, Atul; Do, Synho [MGH Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Brown, Kevin; Thompson, Richard; Morton, Thomas; Raihani, Nilgoun [CT Research and Advanced Development, Philips Healthcare, Cleveland, OH (United States); Koehler, Thomas [Philips Technologie GmbH, Innovative Technologies, Hamburg (Germany); Kalra, Mannudeep K. [MGH Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States)

    2015-01-15

    Highlights: • Limited abdominal CT indications can be performed at a size specific dose estimate of (SSDE) 1.5 mGy (∼0.9 mSv) in smaller patients (BMI less than or equal to 25 kg/m{sup 2}) using a knowledge based Iterative Model Reconstruction (IMR) technique. • Evaluation of liver tumors and pathologies is unacceptable at this reduced dose with IMR technique especially in patients with a BMI greater than 25 kg/m{sup 2}. • IMR body soft tissue and routine settings perform substantially better than IMR sharp plus setting in reduced dose CT images. • At SSDE of 1.5 mGy, objective image noise in reduced dose IMR images is 8–56% less than compared to standard dose FBP images, with lowest image noise in IMR body-soft tissue images. - Abstract: Purpose: To assess lesion detection and image quality parameters of a knowledge-based Iterative Model Reconstruction (IMR) in reduced dose (RD) abdominal CT examinations. Materials and methods: This IRB-approved prospective study included 82 abdominal CT examinations performed for 41 consecutive patients (mean age, 62 ± 12 years; F:M 28:13) who underwent a RD CT (SSDE, 1.5 mGy ± 0.4 [∼0.9 mSv] at 120 kV with 17–20 mAs/slice) immediately after their standard dose (SD) CT exam (10 mGy ± 3 [∼6 mSv] at 120 kV with automatic exposure control) on 256 MDCT (iCT, Philips Healthcare). SD data were reconstructed using filtered back projection (FBP). RD data were reconstructed with FBP and IMR. Four radiologists used a five-point scale (1 = image quality better than SD CT to 5 = image quality unacceptable) to assess both subjective image quality and artifacts. Lesions were first detected on RD FBP images. RD IMR and RD FBP images were then compared side-by-side to SD-FBP images in an independent, randomized and blinded fashion. Friedman's test and intraclass correlation coefficient were used for data analysis. Objective measurements included image noise and attenuation as well as noise spectral density (NSD) curves

  8. Antibiotic prophylaxis for abdominal hysterectomy.

    Science.gov (United States)

    Mele, G; Loizzi, P; Greco, P; Gargano, G; Varcaccio Garofalo, G; Belsanti, A

    1988-01-01

    Three different regimens of antibiotic treatment have been employed in order to evaluate their efficacy as a profilaxis for abdominal hysterectomy. Two short term administrations (Cephtriaxone and Cephamandole plus Tobramycine) and a conventional full dose treatment (Cephazoline) have been compared over a group of homogeneous patients. No significant differences, except a reduction in postoperative time spent in hospital, have been found among the groups. A reduction in urinary tract infection has also been reported with a single-dose antibiotic prophylaxis.

  9. Study on Dim Target Detection and Discrimination from Sea Clutter

    Institute of Scientific and Technical Information of China (English)

    WANG Wen-guang; SUN Zuo-wei; LI Chen-ming; WANG Jun

    2013-01-01

    Dim target detection from sea clutter is one of the difficult topics in ocean remote sensing application.By aiming at the shortcoming of false alarms when using track before detect (TBD) based on dynamic programming,a new discrimination method called statistics of direction histogram (SDH) is proposed,which is based on different features of trajectories between the true target and false one.Moreover,a new series of discrimination schemes of SDH and Local Extreme Value method (LEV) are studied and applied to simulate the actually measured radar data.The results show that the given discrimination is effective to reduce false alarms during dim targets detection.

  10. Improved Multistage Wiener Filters in Nonhomogeneous Clutter Environments

    Institute of Scientific and Technical Information of China (English)

    Bin Tang; Xue-Gang Wang; Ke-Song Chen

    2008-01-01

    A new method combining space-time preprocessing with multistage Wiener filters (STPMWF) is proposed to improve the performance of space-time adaptive processing (STAP) in nonhomogeneous clutter scenario. The new scheme only requires the data from the primary range bin, thus it can suppress discrete interferers efficiently, without calculating the inverse of covariance matrix. Comparing to the original MWF approach, the proposed scheme can be regarded as practical solutions for robust and effective STAP of nonhomogeneous radar data. The theoretical analysis shows that our STPMWF is simple in implementation and fast in convergence. The numeric results by using simulated data exhibit a good agreement with the proposed theory.

  11. Research on Gaussian distribution preprocess method of infrared multispectral image background clutter

    Institute of Scientific and Technical Information of China (English)

    张伟; 武春风; 邓盼; 范宁

    2004-01-01

    This paper introduces a sliding-window mean removal high pass filter by which background clutter of infrared multispectral image is obtained. The method of selecting the optimum size of the sliding-window is based on the skewness-kurtosis test. In the end, a multivariate Gaussian distribution mathematical expression of background clutter image is given.

  12. Object Recognition in Clutter: Cortical Responses Depend on the Type of Learning

    Directory of Open Access Journals (Sweden)

    Jay eHegdé

    2012-06-01

    Full Text Available Theoretical studies suggest that the visual system uses prior knowledge of visual objects to recognize them in visual clutter, and posit that the strategies for recognizing objects in clutter may differ depending on whether or not the object was learned in clutter to begin with. We tested this hypothesis using functional magnetic resonance imaging (fMRI of human subjects. We trained subjects to recognize naturalistic, yet novel objects in strong or weak clutter. We then tested subjects’ recognition performance for both sets of objects in strong clutter. We found many brain regions that were differentially responsive to objects during object recognition depending on whether they were learned in strong or weak clutter. In particular, the responses of the left fusiform gyrus reliably reflected, on a trial-to-trial basis, subjects’ object recognition performance for objects learned in the presence of strong clutter. These results indicate that the visual system does not use a single, general-purpose mechanism to cope with clutter. Instead, there are two distinct spatial patterns of activation whose responses are attributable not to the visual context in which the objects were seen, but to the context in which the objects were learned.

  13. Coherent Surface Clutter Suppression Techniques with Topography Estimation for Multi-Phase-Center Radar Ice Sounding

    DEFF Research Database (Denmark)

    Nielsen, Ulrik; Dall, Jørgen; Kristensen, Steen Savstrup;

    2012-01-01

    Radar ice sounding enables measurement of the thickness and internal structures of the large ice sheets on Earth. Surface clutter masking the signal of interest is a major obstacle in ice sounding. Algorithms for surface clutter suppression based on multi-phase-center radars are presented...

  14. Optimal waveform-based clutter suppression algorithm for recursive synthetic aperture radar imaging systems

    Science.gov (United States)

    Zhu, Binqi; Gao, Yesheng; Wang, Kaizhi; Liu, Xingzhao

    2016-04-01

    A computational method for suppressing clutter and generating clear microwave images of targets is proposed in this paper, which combines synthetic aperture radar (SAR) principles with recursive method and waveform design theory, and it is suitable for SAR for special applications. The nonlinear recursive model is introduced into the SAR operation principle, and the cubature Kalman filter algorithm is used to estimate target and clutter responses in each azimuth position based on their previous states, which are both assumed to be Gaussian distributions. NP criteria-based optimal waveforms are designed repeatedly as the sensor flies along its azimuth path and are used as the transmitting signals. A clutter suppression filter is then designed and added to suppress the clutter response while maintaining most of the target response. Thus, with fewer disturbances from the clutter response, we can generate the SAR image with traditional azimuth matched filters. Our simulations show that the clutter suppression filter significantly reduces the clutter response, and our algorithm greatly improves the SINR of the SAR image based on different clutter suppression filter parameters. As such, this algorithm may be preferable for special target imaging when prior information on the target is available.

  15. Methods of small slow moving targets detection in heavy sea clutter

    Directory of Open Access Journals (Sweden)

    O. D. Mrachkovsky

    2013-07-01

    Full Text Available The search for methods of small targets detection by marine radars is carried out in this paper. As a result of the sources analysis three promising group of methods are selected – adaptive methods based on the clutter amplitude spherically invariant random process representation, methods based on non stohastic clutter representation and methods based on orthogonal transformations. Separately, neural networks and clutter polarization properties are noticed. Most of researches consider compound Gaussian distribution for high resolution sea clutter data modeling. Adaptive CFAR algoritm developed by Kelly for Gaussian clutter was extended for spherical invariant random process. This algorithm can detect target in compound Gaussian clutter and ensure CFAR detection if covariance matrix is precisely known. Many researches proposed different methods of covariance matrix estimating using information from cells adjacent with cell under test. Progress in this field is moving to finding less computation cost but more precise methods of covariance matrix estimation. Further progress for small slow moving targets in heavy sea clutter detection can develop in 3 ways – improving covariance matrix estimation, exploiting not stochastic methods and finding best orthogonal transform for sea clutter Doppler spectrum describing.

  16. Coherent Surface Clutter Suppression Techniques with Topography Estimation for Multi-Phase-Center Radar Ice Sounding

    DEFF Research Database (Denmark)

    Nielsen, Ulrik; Dall, Jørgen; Kristensen, Steen Savstrup

    2012-01-01

    Radar ice sounding enables measurement of the thickness and internal structures of the large ice sheets on Earth. Surface clutter masking the signal of interest is a major obstacle in ice sounding. Algorithms for surface clutter suppression based on multi-phase-center radars are presented. These ...

  17. A NEW METHOD TO COMPENSATE CLUTTER RANGE DEPENDENCE FOR FORWARD LOOKING AIRBORNE RADARS

    Institute of Scientific and Technical Information of China (English)

    Jiang Dongchu; He Fei

    2010-01-01

    The clutter direction-Doppler curves are not aligned on the near range bins for forward looking airborne radar. As a result,the performance of clutter suppression by Space-Time Adaptive Processing (STAP) degrades greatly because of the clutter range dependence. To deal with this problem,a new compensated method is proposed in this paper. The method rebuilds the clutter covariance matrix based on spatial high resolution Minimum Variance Distortionless Response (MVDR) spectrum,and then finds a matrix to transform the covariance matrix of short-range gate to the referred far-range gate. The method can compensate the clutter range dependence well. The simulation results show validity of the method.

  18. Inversion for atmosphere duct parameters using real radar sea clutter

    Science.gov (United States)

    Sheng, Zheng; Fang, Han-Xian

    2012-02-01

    This paper addresses the problem of estimating the lower atmospheric refractivity (M profile) under nonstandard propagation conditions frequently encountered in low altitude maritime radar applications. The vertical structure of the refractive environment is modeled using five parameters and the horizontal structure is modeled using five parameters. The refractivity model is implemented with and without a priori constraint on the duct strength as might be derived from soundings or numerical weather-prediction models. An electromagnetic propagation model maps the refractivity structure into a replica field. Replica fields are compared with the observed clutter using a squared-error objective function. A global search for the 10 environmental parameters is performed using genetic algorithms. The inversion algorithm is implemented on the basis of S-band radar sea-clutter data from Wallops Island, Virginia (SPANDAR). Reference data are from range-dependent refractivity profiles obtained with a helicopter. The inversion is assessed (i) by comparing the propagation predicted from the radar-inferred refractivity profiles with that from the helicopter profiles, (ii) by comparing the refractivity parameters from the helicopter soundings with those estimated. This technique could provide near-real-time estimation of ducting effects.

  19. Inversion for atmosphere duct parameters using real radar sea clutter

    Institute of Scientific and Technical Information of China (English)

    Sheng Zheng; Fang Han-Xian

    2012-01-01

    This paper addresses the problem of estimating the lower atmospheric refractivity (M profile) under nonstandard propagation conditions frequently encountered in low altitude maritime radar applications.The vertical structure of the refractive environment is modeled using five parameters and the horizontal structure is modeled using five parameters.The refractivity model is implemented with and without a priori constraint on the duct strength as might be derived from soundings or numerical weather-prediction models.An electromagnetic propagation model maps the refractivity structure into a replica field.Replica fields are compared with the observed clutter using a squared-error objective function.A global search for the 10 environmental parameters is performed using genetic algorithms.The inversion algorithm is implemented on the basis of S-band radar sea-clutter data from Wallops Island,Virginia (SPANDAR).Reference data are from range-dependent refractivity profiles obtained with a helicopter. The inversion is assessed (i) by comparing the propagation predicted from the radar-inferred refractivity profiles with that from the helicopter profiles,(ii) by comparing the refractivity parameters from the helicopter soundings with those estimated.This technique could provide near-real-time estimation of ducting effects.

  20. Workstation for multispectral multitemporal simulation of targets and clutter

    Science.gov (United States)

    Noah, Paul V.; Noah, Meg A.; Schroeder, John W.; Rudzinsky, Marilyn R.; Bailey, Edward W.

    1992-09-01

    DOD has a requirement to develop and evaluate systems to detect targets against clutter backgrounds. This requires a comprehensive understanding of both target and clutter properties, such as spectral signatures, radiance distributions, edge effects, etc. Acquiring a complete database for all possible physical conditions and instrument parameters is not feasible. To supplement the measured database, Ontar, under two Phase I Small Business Innovative Research (SBIR) contracts to the Naval Surface Warfare Center, and the Naval Weapons Center has developed a workstation for generating radiance maps of complicated objects and performing integrated, multispectral, multitemporal image simulation. The system includes the capability to model targets, atmosphere, clouds, sea surface, natural and man- made terrain features. Currently, the package uses an aircraft model and a first-principle's cloud model. The software, written in FORTRAN, has a user-friendly interface and graphics capabilities. The current software operates on high end PC (80386 and 80486 machines). Results of integrated scene simulation and model validation will be presented.

  1. Wind turbine clutter mitigation in coastal UHF radar.

    Science.gov (United States)

    Yang, Jing; Pan, Chao; Wang, Caijun; Jiang, Dapeng; Wen, Biyang

    2014-01-01

    Coastal UHF radar provides a unique capability to measure the sea surface dynamic parameters and detect small moving targets, by exploiting the low energy loss of electromagnetic waves propagating along the salty and good conducting ocean surface. It could compensate the blind zone of HF surface wave radar at close range and reach further distance than microwave radars. However, its performance is susceptible to wind turbines which are usually installed on the shore. The size of a wind turbine is much larger than the wavelength of radio waves at UHF band, which results in large radar cross section. Furthermore, the rotation of blades adds time-varying Doppler frequency to the clutter and makes the suppression difficult. This paper proposes a mitigation method which is based on the specific periodicity of wind turbine clutter and performed mainly in the time-frequency domain. Field experimental data of a newly developed UHF radar are used to verify this method, and the results prove its effectiveness.

  2. Looking for shapes in two-dimensional cluttered point clouds.

    Science.gov (United States)

    Srivastava, Anuj; Jermyn, Ian H

    2009-09-01

    We study the problem of identifying shape classes in point clouds. These clouds contain sampled points along contours and are corrupted by clutter and observation noise. Taking an analysis-by-synthesis approach, we simulate high-probability configurations of sampled contours using models learned from training data to evaluate the given test data. To facilitate simulations, we develop statistical models for sources of (nuisance) variability: 1) shape variations within classes, 2) variability in sampling continuous curves, 3) pose and scale variability, 4) observation noise, and 5) points introduced by clutter. The variability in sampling closed curves into finite points is represented by positive diffeomorphisms of a unit circle. We derive probability models on these functions using their square-root forms and the Fisher-Rao metric. Using a Monte Carlo approach, we simulate configurations from a joint prior on the shape-sample space and compare them to the data using a likelihood function. Average likelihoods of simulated configurations lead to estimates of posterior probabilities of different classes and, hence, Bayesian classification.

  3. Adaptive clutter rejection for 3D color Doppler imaging: preliminary clinical study.

    Science.gov (United States)

    Yoo, Yang Mo; Sikdar, Siddhartha; Karadayi, Kerem; Kolokythas, Orpheus; Kim, Yongmin

    2008-08-01

    In three-dimensional (3D) ultrasound color Doppler imaging (CDI), effective rejection of flash artifacts caused by tissue motion (clutter) is important for improving sensitivity in visualizing blood flow in vessels. Since clutter characteristics can vary significantly during volume acquisition, a clutter rejection technique that can adapt to the underlying clutter conditions is desirable for 3D CDI. We have previously developed an adaptive clutter rejection (ACR) method, in which an optimum filter is dynamically selected from a set of predesigned clutter filters based on the measured clutter characteristics. In this article, we evaluated the ACR method with 3D in vivo data acquired from 37 kidney transplant patients clinically indicated for a duplex ultrasound examination. We compared ACR against a conventional clutter rejection method, down-mixing (DM), using a commonly-used flow signal-to-clutter ratio (SCR) and a new metric called fractional residual clutter area (FRCA). The ACR method was more effective in removing the flash artifacts while providing higher sensitivity in detecting blood flow in the arcuate arteries and veins in the parenchyma of transplanted kidneys. ACR provided 3.4 dB improvement in SCR over the DM method (11.4 +/- 1.6 dB versus 8.0 +/- 2.0 dB, p < 0.001) and had lower average FRCA values compared with the DM method (0.006 +/- 0.003 versus 0.036 +/- 0.022, p < 0.001) for all study subjects. These results indicate that the new ACR method is useful for removing nonstationary tissue motion while improving the image quality for visualizing 3D vascular structure in 3D CDI.

  4. Ground clutter cancellation in incoherent radars: solutions for EISCAT Svalbard radar

    Directory of Open Access Journals (Sweden)

    T. Turunen

    Full Text Available Incoherent scatter radars measure ionosphere parameters using modified Thomson scatter from free electrons in the target (see e.g. Hagfors, 1997. The integrated cross section of the ionospheric scatterers is extremely small and the measurements can easily be disturbed by signals returned by unwanted targets. Ground clutter signals, entering via the antenna side lobes, can render measurements at the nearest target ranges totally impossible. The EISCAT Svalbard Radar (ESR, which started measurements in 1996, suffers from severe ground clutter and the ionosphere cannot be measured in any simple manner at ranges less than about 120–150 km, depending on the modulation employed. If the target and clutter signals have different, and clearly identifiable, properties then, in principle, there are always ways to eliminate the clutter. In incoherent scatter measurements, differences in the coherence times of the wanted and unwanted signals can be used for clutter cancellation. The clutter cancellation must be applied to all modulations, usually alternating codes in modern experiments, used for shorter ranges. Excellent results have been obtained at the ESR using a simple pulse-to-pulse clutter subtraction method, but there are also other possibilities.

    Key words: Radio science (ionospheric physics; signal processing; instruments and techniques

  5. Ground clutter cancellation in incoherent radars: solutions for EISCAT Svalbard radar

    Science.gov (United States)

    Turunen, T.; Markkanen, J.; van Eyken, A. P.

    2000-09-01

    Incoherent scatter radars measure ionosphere parameters using modified Thomson scatter from free electrons in the target (see e.g. Hagfors, 1997). The integrated cross section of the ionospheric scatterers is extremely small and the measurements can easily be disturbed by signals returned by unwanted targets. Ground clutter signals, entering via the antenna side lobes, can render measurements at the nearest target ranges totally impossible. The EISCAT Svalbard Radar (ESR), which started measurements in 1996, suffers from severe ground clutter and the ionosphere cannot be measured in any simple manner at ranges less than about 120-150 km, depending on the modulation employed. If the target and clutter signals have different, and clearly identifiable, properties then, in principle, there are always ways to eliminate the clutter. In incoherent scatter measurements, differences in the coherence times of the wanted and unwanted signals can be used for clutter cancellation. The clutter cancellation must be applied to all modulations, usually alternating codes in modern experiments, used for shorter ranges. Excellent results have been obtained at the ESR using a simple pulse-to-pulse clutter subtraction method, but there are also other possibilities.

  6. Observer detection and discrimination performance as a function of clutter: a signal detection approach

    Science.gov (United States)

    Bora, Archana; Aggarwal, Tarun; Lakshminarayanan, Vasudevan

    2011-11-01

    In this paper we investigate the use of signal detection theory (SDT) in predicting target detection and discrimination in disorganized clutter. Two normal observers performed monocular visual search experiments at 25 cm, in the dark. They detected Gabor gratings on an achromatic background cluttered with 2000 or 500 random dots. The targets were displayed at pseudorandom locations from 0-20° and 20-47°, by method of constant stimuli. A contrast-based detection and orientation-based discrimination task was completed in a yes/no or 2-alternative-forced-choice (2AFC) task. The hit rate, false alarm rate, detectability, criterion and bias were analysed. The psychometric function indicated low detection and discrimination thresholds in low clutter that increased in high clutter. Increased clutter showed high hit rates and a false alarm rate that increased with low detectability and liberal criterion. In the detection task, low clutter showed high hit rates and low false alarm rates in the central field. Therefore, SDT proves useful to predict observer performance in visual scenes with disorganized clutter.

  7. Bayesian Contrast Measures and Clutter Distribution Determinants of Human Target Detection.

    Science.gov (United States)

    Novak, Ana; Armstrong, Nicholas; Caelli, Terry; Blair, Iain

    2017-03-01

    Human target detection is known to be dependent on a number of components: one, basic electro-optics including image contrast, the target size, pixel resolution, and contrast sensitivity; two, target shape, image type and features, types of clutter; and three, context and task requirements. Here, we consider a Bayesian approach to investigating how these components contribute to target detection. To this end, we develop and compare three different formulations for contrast: mean contrast, perceptual contrast, and a Bayesian-based histogram contrast statistic. Results on past detection data show how the latter contrast measure correlates well with human performance factoring out all other dimensions. As for clutter, our findings show that with large targets, there are effectively no clutter effects. Furthermore, clutter does not have a major effect on detection when it is not contiguous with the target even when it is smaller. However, except for large targets, when the target is contiguous with the clutter, detection clearly decreases as a function of the similarity of target and clutter features-creating type of "clutter camouflage". This Bayesian formulation uses priors based on the contrast histogram statistics derived from all the images, the image context, and implies that human observers have adapted their criteria to fit with the image set, context, and task.

  8. Weak Target Detection within the Nonhomogeneous Ionospheric Clutter Background of HFSWR Based on STAP

    Directory of Open Access Journals (Sweden)

    Xin Zhang

    2013-01-01

    Full Text Available High Frequency Surface Wave Radar (HFSWR can perform the functions of ocean environment monitoring, target detection, and target tracking over the horizon. However, its system's performance is always limited by the severe ionospheric clutter environment, especially by the nonhomogeneous component. The nonhomogeneous ionospheric clutter generally can cover a few Doppler shift units and a few angle units. Consequently, weak targets masked by the nonhomogeneous ionospheric clutter are difficult to be detected. In this paper, a novel algorithm based on angle-Doppler joint eigenvector which considers the angle-Doppler map of radar echoes is adopted to analyze the characteristics of the nonhomogeneous ionospheric clutter. Given the measured data set, we first investigate the correlation between the signal of interest (SOI and the nonhomogeneous ionospheric clutter and then the correlation between the nonhomogeneous ionospheric clutters in different two ranges. Finally, a new strategy of training data selection is proposed to improve the joint domain localised (JDL algorithm. Simulation results show that the improved-JDL algorithm is effective and the performance of weak target detection within nonhomogeneous ionospheric clutter is improved.

  9. Ground-Vegetation Clutter Affects Phyllostomid Bat Assemblage Structure in Lowland Amazonian Forest.

    Science.gov (United States)

    Marciente, Rodrigo; Bobrowiec, Paulo Estefano D; Magnusson, William E

    2015-01-01

    Vegetation clutter is a limiting factor for bats that forage near ground level, and may determine the distribution of species and guilds. However, many studies that evaluated the effects of vegetation clutter on bats have used qualitative descriptions rather than direct measurements of vegetation density. Moreover, few studies have evaluated the effect of vegetation clutter on a regional scale. Here, we evaluate the influence of the physical obstruction of vegetation on phyllostomid-bat assemblages along a 520 km transect in continuous Amazonian forest. We sampled bats using mist nets in eight localities during 80 nights (3840 net-hours) and estimated the ground-vegetation density with digital photographs. The total number of species, number of animalivorous species, total number of frugivorous species, number of understory frugivorous species, and abundance of canopy frugivorous bats were negatively associated with vegetation clutter. The bat assemblages showed a nested structure in relation to degree of clutter, with animalivorous and understory frugivorous bats distributed throughout the vegetation-clutter gradient, while canopy frugivores were restricted to sites with more open vegetation. The species distribution along the gradient of vegetation clutter was not closely associated with wing morphology, but aspect ratio and wing load differed between frugivores and animalivores. Vegetation structure plays an important role in structuring assemblages of the bats at the regional scale by increasing beta diversity between sites. Differences in foraging strategy and diet of the guilds seem to have contributed more to the spatial distribution of bats than the wing characteristics of the species alone.

  10. Modern Approaches to the Computation of the Probability of Target Detection in Cluttered Environments

    Science.gov (United States)

    Meitzler, Thomas J.

    The field of computer vision interacts with fields such as psychology, vision research, machine vision, psychophysics, mathematics, physics, and computer science. The focus of this thesis is new algorithms and methods for the computation of the probability of detection (Pd) of a target in a cluttered scene. The scene can be either a natural visual scene such as one sees with the naked eye (visual), or, a scene displayed on a monitor with the help of infrared sensors. The relative clutter and the temperature difference between the target and background (DeltaT) are defined and then used to calculate a relative signal -to-clutter ratio (SCR) from which the Pd is calculated for a target in a cluttered scene. It is shown how this definition can include many previous definitions of clutter and (DeltaT). Next, fuzzy and neural -fuzzy techniques are used to calculate the Pd and it is shown how these methods can give results that have a good correlation with experiment. The experimental design for actually measuring the Pd of a target by observers is described. Finally, wavelets are applied to the calculation of clutter and it is shown how this new definition of clutter based on wavelets can be used to compute the Pd of a target.

  11. Study of clutter origin in in-vivo epi-optoacoustic imaging of human forearms

    Science.gov (United States)

    Preisser, Stefan; Held, Gerrit; Akarçay, Hidayet G.; Jaeger, Michael; Frenz, Martin

    2016-09-01

    Epi-optoacoustic (OA) imaging offers flexible clinical diagnostics of the human body when the irradiation optic is attached to or directly integrated into the acoustic probe. Epi-OA images, however, encounter clutter that deteriorates contrast and significantly limits imaging depth. This study elaborates clutter origin in clinical epi-optoacoustic imaging using a linear array probe for scanning the human forearm. We demonstrate that the clutter strength strongly varies with the imaging location but stays stable over time, indicating that clutter is caused by anatomical structures. OA transients which are generated by strong optical absorbers located at the irradiation spot were identified to be the main source of clutter. These transients obscure deep in-plane OA signals when detected by the transducer either directly or after being acoustically scattered in the imaging plane. In addition, OA transients generated in the skin below the probe result in acoustic reverberations, which cause problems in image interpretation and limit imaging depth. Understanding clutter origin allows a better interpretation of clinical OA imaging, helps to design clutter compensation techniques and raises the prospect of contrast optimization via the design of the irradiation geometry.

  12. Effect of the dose and route of administration of butylscopolamine on the reduction of the artifacts associated with intestinal peristalsis in abdominal magnetic resonance; Efecto de la dosis y la via de administracion de butilescopolamina en la disminucion de los artefactors asociados al peristaltismo intestinal en la RM abdominal

    Energy Technology Data Exchange (ETDEWEB)

    Dosda, R.; Marti-Bonmati, L. [Hospital Universitario Dr Peset. Valencia. Clinica Quiron. Valencia (Spain); Ronchera-Oms, C. [Hospital San Pablo-CEU. Moncada Valencia (Spain)

    1999-07-01

    To compare the effect of the route of administration (intravenous and oral) and the dose (40 mg and 80 mg) of butylscopolamine, determining its efficacy in reducing the noise associated with gastrointestinal movement in magnetic resonance (MR) images and the incidence and severity of associated adverse reactions. The present prospective, controlled, double-blind study included 80 patients who underwent abdominal MR. All the patients were given oral, high-density barium sulfate and were divided randomly into 4 groups of 20 patients each: a control group and 3 groups treated with 40 mg or 80 mg of oral butylscopolamine or 40 mg of intravenous butylscopolamine. Both the barium and the oral solutions were administered 25 to 30 minutes before the examination. the MR images were obtained with a STIR sequence (1487/100/44), and qualitative analysis of the noise was carried out using regions of interest situated in the background. The gastrointestinal noise was defined both by the mean and the standard deviation of the signal intensity of the air front of an behind the patient. The standard deviation of the air beside the patient was determined to confirm the absence of variations in noise inherent to MR. The adverse reactions to MR after 2 hours (immediate) and one day (late) were recorded. There were no significant differences among the groups with respect to sex, age or time interval between administration of the oral solution and the start of the sequence. The noise inherent to MR was not significantly different from one group to another (Student-Newman-Keuls test, p=0.71). Both the mean and the standard deviation of the intensity of the air situated in anteroposterior phase-encoding direction were significantly lower in the butylscopolamine groups than in the control group (Student-Newman-Keuls test, p=0.008). The most marked reduction was observed after the oral dose of 80 mg, followed by intravenous injection of 40 mg and the oral dose of 40 mg. Adverse reaction

  13. Abdominal binders may reduce pain and improve physical function after major abdominal surgery - a systematic review

    DEFF Research Database (Denmark)

    Rothman, Josephine Philip; Gunnarsson, Ulf; Bisgaard, Thue

    2014-01-01

    INTRODUCTION: Evidence for the effect of post-operative abdominal binders on post-operative pain, seroma formation, physical function, pulmonary function and increased intra-abdominal pressure among patients after surgery remains largely un-investigated. METHODS: A systematic review was conducted....... The PubMed, EMBASE and Cochrane databases were searched for studies on the use of abdominal binders after abdominal surgery or abdominoplasty. All types of clinical studies were included. Two independent assessors evaluated the scientific quality of the studies. The primary outcomes were pain, seroma...... to reduce seroma formation after laparoscopic ventral herniotomy and a non-significant reduction in pain. Physical function was improved, whereas evidence supports a beneficial effect on psychological distress after open abdominal surgery. Evidence also supports that intra-abdominal pressure increases...

  14. Abdominal radiation - discharge

    Science.gov (United States)

    Radiation - abdomen - discharge; Cancer - abdominal radiation; Lymphoma - abdominal radiation ... When you have radiation treatment for cancer, your body goes through changes. About 2 weeks after radiation treatment starts, you might notice changes ...

  15. Abdominal and Pelvic CT

    Medline Plus

    Full Text Available ... accurate. In emergency cases, it can reveal internal injuries and bleeding quickly enough to help save lives. ... kidney and bladder stones. abdominal aortic aneurysms (AAA), injuries to abdominal organs such as the spleen, liver, ...

  16. Abdominal and Pelvic CT

    Medline Plus

    Full Text Available ... accurate. In emergency cases, it can reveal internal injuries and bleeding quickly enough to help save lives. ... kidney and bladder stones. abdominal aortic aneurysms (AAA), injuries to abdominal organs such as the spleen, liver, ...

  17. Abdominal aortic aneurysm

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000162.htm Abdominal aortic aneurysm To use the sharing features on this page, ... blood to the abdomen, pelvis, and legs. An abdominal aortic aneurysm occurs when an area of the aorta becomes ...

  18. Post trauma abdominal cocoon.

    Science.gov (United States)

    Kaur, Supreet; Doley, Rudra Prasad; Chabbhra, Mohinish; Kapoor, Rajeev; Wig, Jaidev

    2015-01-01

    Abdominal cocoon or sclerosing peritonitis refers to a rare cause of intestinal obstruction due to formation of a membrane encasing the bowel. We report a case of abdominal cocoon post blunt trauma abdomen. The patient presented with a history of subacute intestinal obstruction and a mobile abdomen lump. Abdominal cocoon was diagnosed on computed tomography. He underwent adhesiolysis with excision of membrane.

  19. Abdominal wall fat pad biopsy

    Science.gov (United States)

    Amyloidosis - abdominal wall fat pad biopsy; Abdominal wall biopsy; Biopsy - abdominal wall fat pad ... method of taking an abdominal wall fat pad biopsy . The health care provider cleans the skin on ...

  20. Hardware in the loop simulation of arbitrary magnitude shaped correlated radar clutter

    CSIR Research Space (South Africa)

    Strydom, JJ

    2014-10-01

    Full Text Available This paper describes a simple process for the generation of arbitrary probability distributions of complex data with correlation from sample to sample, optimized for hardware in the loop radar environment simulation. Measured radar clutter is used...

  1. Intermittent Clutter Removal Approac for wind Profiler Data Based on Fractional Fourier Transform

    Institute of Scientific and Technical Information of China (English)

    YUAN Lei; AN Jian-ping; BU Xiang-yuan

    2009-01-01

    Through the analysis of the target characteristics and according to the intermittent clutter bursting and short duration characteristics, a new method for the clutter recognition based on the fractional Fourier transform (FRFT) is proposed. This method is predicated on the fact that the FRFT perfectly localizes a chirp signal as an impulse when the angle parameter of the transform matches the chirp rate of the chirp signal. The method involves detecting the presence of the intermittent clutter and correctly estimating its orientation in the time-frequency plane, removing the intermittent clutter in the fractional domain, and completing wind estimation by the power spectrum. By testing the artificial WPR-like signal and data measured from the field, we verify that the FRFT-based method is very effective.

  2. A Clutter Suppression Approach for SAR-GMTI Based on Dual-channel DPCA

    Directory of Open Access Journals (Sweden)

    Wang Xiao-yang

    2014-04-01

    Full Text Available The Displaced Phase Center Antenna (DPCA technology, a particular form of Space Time Adaptive Processing (STAP, has been widely used in Synthetic Aperture Radar Ground Moving Target Indication (SAR-GMTI. The GMTI performance depends on the capability of clutter rejection but the traditional DPCA technology operated in the complex image domain does not have the appropriate clutter rejection capability for urban areas with strong scattering stationary objects. Hence, interferometry phase is used to weight the DPCA magnitude nonlinearly, and a weighted DPCA clutter rejection approach is proposed, which reduces the interference from residual phase difference. The experimental results suggest that the new approach can improve the clutter rejection compared with the conventional DPCA.

  3. Clutter attenuation using the Doppler effect in standoff electromagnetic quantum sensing

    Science.gov (United States)

    Lanzagorta, Marco; Jitrik, Oliverio; Uhlmann, Jeffrey; Venegas, Salvador

    2016-05-01

    In the context of traditional radar systems, the Doppler effect is crucial to detect and track moving targets in the presence of clutter. In the quantum radar context, however, most theoretical performance analyses to date have assumed static targets. In this paper we consider the Doppler effect at the single photon level. In particular, we describe how the Doppler effect produced by clutter and moving targets modifies the quantum distinguishability and the quantum radar error detection probability equations. Furthermore, we show that Doppler-based delayline cancelers can reduce the effects of clutter in the context of quantum radar, but only in the low-brightness regime. Thus, quantum radar may prove to be an important technology if the electronic battlefield requires stealthy tracking and detection of moving targets in the presence of clutter.

  4. Abdominal-pelvic scanning parameters revisited: a case for Z-axis reduction in patients with clinical suspicion for acute appendicitis.

    Science.gov (United States)

    Patel, Darshan C; Huang, Yu-Hui; Meyer, Jonathan; Sepahdari, Amir

    2017-07-27

    The purpose of this study was to determine if CT for appendicitis can be abbreviated to begin at the top of the L2 vertebral body level and still maintain the detection rate of appendicitis and other symptomatic pathology without omitting significant incidental findings. Retrospective review of CT abdomen-pelvis exams for suspected appendicitis over a 5-month period was performed. The Z-axis scan length of the original full scans and theoretical limited scans from the top of L2 were recorded and calculated. Images were reviewed for incidental findings above the L2 vertebral body level and categorized by severity per American College of Radiology (ACR) white paper guidelines. Final diagnoses based on imaging findings were also recorded. One hundred nineteen patients (46 males, 73 females, mean age 29 ± 14) were included. Appendicitis was present in 26 cases (22%). Using a theoretical scan beginning at the top of the L2 vertebral body, none of the findings leading to diagnosis of appendicitis would have been missed. A total of 30 incidental findings were found above the L2 vertebral body. Per ACR white paper guidelines, 26 of these findings did not require additional imaging follow-up. Additional follow-up imaging was recommended for 3 of the findings above L2, and 1 right adrenal metastasis was found above L2 in a patient with previously undiagnosed NSCLC. This patient coincidentally also had appendicitis. No symptomatic pathology would have been missed had the scans begun at the top of the L2 vertebral body. Such an abbreviated scan would have resulted in a mean Z-axis reduction of 12.9 cm (30.3%). CT using abbreviated Z-axis scan length can reduce radiation dose and provide necessary imaging needed to diagnose appendicitis or other symptomatic pathology without omitting significant incidental findings.

  5. A Polarization Technique for Mitigating Low Grazing Angle Radar Sea Clutter

    Science.gov (United States)

    2017-03-03

    A Polarization Technique for Mitigating Low-Grazing-Angle Radar Sea Clutter Molly K. Crane MIT Lincoln Laboratory Lexington, MA 02420 Email...MA 02420 Email: mabel.ramirez@ll.mit.edu Abstract—Traditional detection schemes in conventional mar- itime surveillance radars may suffer serious...effective means of enhancing target detection in sea clutter, MIT Lincoln Laboratory (MIT LL) collected a fully polarimetric X-band radar dataset on

  6. Analysis and Modeling of Multistatic Clutter and Reverberation and Support for the FORA

    Science.gov (United States)

    2014-09-30

    ABSTRACT Same as Report ( SAR ) 18. NUMBER OF PAGES 8 19a. NAME OF RESPONSIBLE PERSON a. REPORT unclassified b. ABSTRACT unclassified c. THIS...effort, the PI completed work to statistically characterize the bistatic bottom clutter and shipwreck echoes seen in the Clutter07 data sets using...Reverberation Modeling Workshop proceedings, Apr. 2007. [14] Dale D. Ellis, John R. Preston, Paul C. Hines, and Victor W. Young, Bistatic signal excess

  7. Advanced methods and means to improve atmospheric lidar stability against sky background clutter

    Science.gov (United States)

    Agishev, Ravil R.

    2011-11-01

    An impact of intensive background clutter on lidar photodetectors leads to changes of their sensitivity and can even overload them. As a result, information on atmospheric optical parameters is distorted and sometimes can be completely lost. Since a problem of lidar system structure and parameters adaptation to background radiation remains actual one, some advanced methods and means to improve atmospheric lidar stability against sky background clutter are discussed.

  8. Language planning disturbances in children who clutter or have learning disabilities.

    Science.gov (United States)

    van Zaalen-Op't Hof, Yvonne; Wijnen, Frank; Dejonckere, Philip

    2009-01-01

    The primary objective of this paper is to determine to what extent disturbances in the fluency of language production of children who clutter might be related to, or differ from difficulties in the same underlying processes of language formulation seen in children with learning disabilities. It is hypothesized that an increase in normal dysfluencies and sentence revisions in children who clutter reflect different neurolinguistic process to those of children with learning disabilities. To test this idea, 150 Dutch speaking children, aged 10;6 to 12;11 years, were divided in three groups (cluttering, learning difficulties and controls), and a range of speech and language variables were analysed. Results indicate differences in the underlying processes of language disturbances between children with cluttered speech and those with learning disabilities. Specifically, language production of children with learning disabilities was disturbed by problems at the conceptualizator and formulator stages of Levelt's language processing model, whilst language planning disturbances in children who clutter were considered to arise due to insufficient time to complete the editing phase of sentence structuring. These findings indicate that children who clutter can be differentiated from children with learning disabilities by both the number of main and secondary story plot elements and by the percentage of correct sentence structures.

  9. Eigen-based clutter filter design for ultrasound color flow imaging: a review.

    Science.gov (United States)

    Yu, Alfred; Lovstakken, Lasse

    2010-05-01

    Proper suppression of tissue clutter is a prerequisite for visualizing flow accurately in ultrasound color flow imaging. Among various clutter suppression methods, the eigen-based filter has shown potential because it can theoretically adapt its stopband to the actual clutter characteristics even when tissue motion is present. This paper presents a formative review on how eigen-based filters should be designed to improve their practical efficacy in adaptively suppressing clutter without affecting the blood flow echoes. Our review is centered around a comparative assessment of two eigen-filter design considerations: 1) eigen-component estimation approach (single-ensemble vs. multi-ensemble formulations), and 2) filter order selection mechanism (eigenvalue-based vs. frequencybased algorithms). To evaluate the practical efficacy of existing eigen-filter designs, we analyzed their clutter suppression level in two in vivo scenarios with substantial tissue motion (intra-operative coronary imaging and thyroid imaging). Our analysis shows that, as compared with polynomial regression filters (with or without instantaneous clutter downmixing), eigen-filters that use a frequency-based algorithm for filter order selection generally give Doppler power images with better contrast between blood and tissue regions. Results also suggest that both multi-ensemble and single-ensemble eigen-estimation approaches have their own advantages and weaknesses in different imaging scenarios. It may be beneficial to develop an algorithmic way of defining the eigen-filter formulation so that its performance advantages can be better realized.

  10. Hérnia traumática da parede abdominal Traumatic abdominal hernia

    Directory of Open Access Journals (Sweden)

    Alexandre Cruz Henriques

    1999-10-01

    Full Text Available A rare case of blunt traumatic abdominal hernia is presented in which jejunal loops herniated through the abdominal wall. The patient had a serious motor vehicle accident seven years ago, while wearing the seat belt. He developed a traumatic hernia in the anterior lateral abdominal wall, which was operated, and relapsed after some months. The patient was reoperated and we observed the unattachment of the anterior lateral abdominal musculature from the ilium crest. After the hernial sac treatment, the defect was solved with the use of a polypropylene mesh. The postoperative evolution was good and four months later there were no signs of recurrence. Traumatic abdominal hernia remains a rare clinical entity, despite the increase in blunt abdominal trauma. Traumatic abdominal wall hernia falls into two general categories: small lower quadrant abdominal defects, typically the result of blunt trauma with bicycle handlebars, and larger abdominal wall defects related to motor vehicle accidents. The diagnosis may be often established by the physical examination alone. Conventional radiology and computerized tomography usefulness have been proved. In the vast majority of cases, early repair is recommended. The appropriate treatment is the reduction of the herniated bowel into the abdomen, the debridment of nonviable tissues, and a primary tension free closure of the detect.

  11. Abdominal epilepsy in chronic recurrent abdominal pain

    Directory of Open Access Journals (Sweden)

    V Y Kshirsagar

    2012-01-01

    Full Text Available Background: Abdominal epilepsy (AE is an uncommon cause for chronic recurrent abdominal pain in children and adults. It is characterized by paroxysmal episode of abdominal pain, diverse abdominal complaints, definite electroencephalogram (EEG abnormalities and favorable response to the introduction of anti-epileptic drugs (AED. We studied 150 children with chronic recurrent abdominal pain and after exclusion of more common etiologies for the presenting complaints; workup proceeded with an EEG. We found 111 (74% children with an abnormal EEG and 39 (26% children with normal EEG. All children were subjected to AED (Oxcarbazepine and 139 (92% children responded to AED out of which 111 (74% children had an abnormal EEG and 27 (18% had a normal EEG. On further follow-up the patients were symptom free, which helped us to confirm the clinical diagnosis. Context: Recurrent chronic abdominal pain is a common problem encountered by pediatricians. Variety of investigations are done to come to a diagnosis but a cause is rarely found. In such children diagnosis of AE should be considered and an EEG will confirm the diagnosis and treated with AED. Aims: To find the incidence of AE in children presenting with chronic recurrent abdominal pain and to correlate EEG findings and their clinical response to empirical AEDs in both cases and control. Settings and Design: Krishna Institute of Medical Sciences University, Karad, Maharashtra, India. Prospective analytical study. Materials and Methods: A total of 150 children with chronic recurrent abdominal pain were studied by investigations to rule out common causes of abdominal pain and an EEG. All children were then started with AED oxycarbamezepine and their response to the treatment was noted. Results: 111 (74% of the total 150 children showed a positive EEG change suggestive of epileptogenic activity and of which 75 (67.56% were females and 36 (32.43% were male, majority of children were in the age of group of 9

  12. Abdominal Decompression in Children

    Directory of Open Access Journals (Sweden)

    J. Chiaka Ejike

    2012-01-01

    Full Text Available Abdominal compartment syndrome (ACS increases the risk for mortality in critically ill children. It occurs in association with a wide variety of medical and surgical diagnoses. Management of ACS involves recognizing the development of intra-abdominal hypertension (IAH by intra-abdominal pressure (IAP monitoring, treating the underlying cause, and preventing progression to ACS by lowering IAP. When ACS is already present, supporting dysfunctional organs and decreasing IAP to prevent new organ involvement become an additional focus of therapy. Medical management strategies to achieve these goals should be employed but when medical management fails, timely abdominal decompression is essential to reduce the risk of mortality. A literature review was performed to understand the role and outcomes of abdominal decompression among children with ACS. Abdominal decompression appears to have a positive effect on patient survival. However, prospective randomized studies are needed to fully understand the indications and impact of these therapies on survival in children.

  13. Ground-Vegetation Clutter Affects Phyllostomid Bat Assemblage Structure in Lowland Amazonian Forest.

    Directory of Open Access Journals (Sweden)

    Rodrigo Marciente

    Full Text Available Vegetation clutter is a limiting factor for bats that forage near ground level, and may determine the distribution of species and guilds. However, many studies that evaluated the effects of vegetation clutter on bats have used qualitative descriptions rather than direct measurements of vegetation density. Moreover, few studies have evaluated the effect of vegetation clutter on a regional scale. Here, we evaluate the influence of the physical obstruction of vegetation on phyllostomid-bat assemblages along a 520 km transect in continuous Amazonian forest. We sampled bats using mist nets in eight localities during 80 nights (3840 net-hours and estimated the ground-vegetation density with digital photographs. The total number of species, number of animalivorous species, total number of frugivorous species, number of understory frugivorous species, and abundance of canopy frugivorous bats were negatively associated with vegetation clutter. The bat assemblages showed a nested structure in relation to degree of clutter, with animalivorous and understory frugivorous bats distributed throughout the vegetation-clutter gradient, while canopy frugivores were restricted to sites with more open vegetation. The species distribution along the gradient of vegetation clutter was not closely associated with wing morphology, but aspect ratio and wing load differed between frugivores and animalivores. Vegetation structure plays an important role in structuring assemblages of the bats at the regional scale by increasing beta diversity between sites. Differences in foraging strategy and diet of the guilds seem to have contributed more to the spatial distribution of bats than the wing characteristics of the species alone.

  14. Abdominal Compartment Syndrome

    OpenAIRE

    Ovchinnikov V.А.; Sokolov V.А.

    2013-01-01

    We considered one of the most complicated problems of surgery and intensive care — abdominal compartment syndrome. It is a severe, and in some cases lethal complication developing in major injuries and pathology of abdominal cavity and retroperitoneal space, as well as in extra-abdominal pathology. In addition, compartment syndrome can be the complication of a number of surgical procedures accompanied primarily by laparotomy wound closure with tissue tension. We demonstrated the classificatio...

  15. Post trauma abdominal cocoon

    Directory of Open Access Journals (Sweden)

    Supreet Kaur

    2015-01-01

    Full Text Available Abdominal cocoon or sclerosing peritonitis refers to a rare cause of intestinal obstruction due to formation of a membrane encasing the bowel. We report a case of abdominal cocoon post blunt trauma abdomen. The patient presented with a history of subacute intestinal obstruction and a mobile abdomen lump. Abdominal cocoon was diagnosed on computed tomography. He underwent adhesiolysis with excision of membrane.

  16. Abdominal Compartment Syndrome

    Directory of Open Access Journals (Sweden)

    Pınar Zeyneloğlu

    2015-04-01

    Full Text Available Intraabdominal hypertension and Abdominal compartment syndrome are causes of morbidity and mortality in critical care patients. Timely diagnosis and treatment may improve organ functions. Intra-abdominal pressure monitoring is vital during evaluation of the patients and in the management algorithms. The incidence, definition and risk factors, clinical presentation, diagnosis and management of intraabdominal hypertension and Abdominal compartment syndrome were reviewed here.

  17. Influence of the adaptive iterative dose reduction 3D algorithm on the detectability of low-contrast lesions and radiation dose repeatability in abdominal computed tomography: a phantom study.

    Science.gov (United States)

    Yoon, Jeong Hee; Lee, Jeong Min; Hur, Bo Yun; Baek, Jeehyun; Shim, Hackjoon; Han, Joon Koo; Choi, Byung Ihn

    2015-08-01

    The purpose of the study is to evaluate the influence of the adaptive iterative dose reduction (AIDR 3D) algorithm on the detectability of low-contrast focal liver lesions (FLLs) and the radiation dose repeatability of automatic tube current modulation (ATCM) in abdominal CT scans using anthropomorphic phantoms. Three different sizes of anthropomorphic phantoms, each with 4 low-contrast FLLs, were scanned on a 320-channel CT scanner using the ATCM technique and AIDR 3D, at different radiation doses: full-dose, half-dose, and quarter-dose. Scans were repeated three times and reconstructed with filtered back projection (FBP) and AIDR 3D. Radiation dose repeatability was assessed using the intraclass correlation coefficient (ICC). Image noise, quality, and lesion conspicuity were assessed by four reviewers and the number of invisible FLLs was compared among different radiation doses and reconstruction methods. ICCs of radiation dose among the three CT scans were excellent in all phantoms (0.99). Image noise, quality, and lesion conspicuity in the half-dose group were comparable with full-dose FBP after applying AIDR 3D in all phantoms. In small phantoms, the half-dose group reconstructed with AIDR 3D showed similar sensitivity in visualizing low-contrast FLLs compared to full-dose FBP (P = 0.77-0.84). In medium and large phantoms, AIDR 3D reduced the number of missing low-contrast FLLs [3.1% (9/288), 11.5% (33/288), respectively], compared to FBP [10.4% (30/288), 21.9% (63/288), respectively] in the full-dose group. By applying AIDR 3D, half-dose CT scans may be achievable in small-sized patients without hampering diagnostic performance, while it may improve diagnostic performance in medium- and large-sized patients without increasing the radiation dose.

  18. Radar cross sections of ground clutter at 95 GHz for summer and fall conditions

    Science.gov (United States)

    Wellman, R. J.; Hutchins, D. R.; Silvious, J. L.; Dropkin, H.; Goldman, G.; Nemarich, J.; Wikner, D. A.; Dahlstrom, R. K.

    1993-11-01

    Radar cross section (RCS) measurements were made on an extensively instrumented ground-clutter patch over a period of one month from late summer to early fall. The instrumentation allowed collection of a full set of data on meteorological conditions, solar flux, and soil moisture content. The RCS measurements were made using a 95-GHz, polarimetric, monopulse instrumentation radar. The radar is all solid-state, coherent, frequency steppable over a 640-MHz bandwidth, and completely polarimetric for linearly or circularly polarized radiation. The clutter area measured was located in Grayling, Michigan, and consisted of a rectangular patch of ground, 50 by 100 m in area, at a range of about 100 to 250 m from the radar. The clutter patch included areas of bare sandy ground, short grass, low shrubs, evergreen trees, and deciduous trees and was similar to a NATO European environment. A wide range of atmospheric conditions were observed over the measurement period, including a few days of measurable snowfall. The paper describes analysis of the effects of different clutter types and different atmospheric conditions on the measured RCS of the clutter patch.

  19. Main sea clutter characteristics impacting small slow moving targets detection by marine radars

    Directory of Open Access Journals (Sweden)

    O. D. Mrachkovskiy

    2013-04-01

    Full Text Available Searching of the sea clutter mathematical model is carried out in this paper. It is suitable to create based on it algorithm for small slow moving targets detection by marine radars. The compound Gaussian model for modeling sea clutter amplitude stochastic distribution is selected as a result of the sources analysis, because it was confirmed by most of researches. The discussed in the literature model based on chaos theory is choosen as perspective alternative for stochastic model; its advantage of using it for such problems solution must be definitively proved or denied. It was proposed many different distributions for high resolution sea clutter amplitude data modeling. The most frequently reported in the literature are K, Log-Normal and Weibull distributions. K distribution belonging to a compound-Gaussian model has the most significant theoretical and experimental background. This distribution choice is physically explained basing on the processes taking place when electromagnetic waves scattered from capillarity and gravity sea waves create a composed echo. Signal representing this echo is the product of two random components, called texture and speckle. Texture is the result of scattering from gravity waves, has a Gamma pdf (in case of K distribution and corresponds to slow-varying large-scale structure. Speckle is the result of scattering from isolated scatterers (capillarity waves, has a Rayleigh pdf and corresponds to rapid varying small-scale structure. So, K distribution envelope is a compound distribution consisting of a locally Rayleigh distribution speckle whose mean is modulated by a gamma distribution texture. All researches consider Rayleigh pdf for speckle. The lognormal, generalized Gaussian, inverse gamma and some other distributions were proposed for the texture. Due to literature analyses it is seen that texture distribution depends on radar range resolution, but strong dependence is not proved. Some scientists modified K

  20. Parametric Coding of the Size and Clutter of Natural Scenes in the Human Brain.

    Science.gov (United States)

    Park, Soojin; Konkle, Talia; Oliva, Aude

    2015-07-01

    Estimating the size of a space and its degree of clutter are effortless and ubiquitous tasks of moving agents in a natural environment. Here, we examine how regions along the occipital-temporal lobe respond to pictures of indoor real-world scenes that parametrically vary in their physical "size" (the spatial extent of a space bounded by walls) and functional "clutter" (the organization and quantity of objects that fill up the space). Using a linear regression model on multivoxel pattern activity across regions of interest, we find evidence that both properties of size and clutter are represented in the patterns of parahippocampal cortex, while the retrosplenial cortex activity patterns are predominantly sensitive to the size of a space, rather than the degree of clutter. Parametric whole-brain analyses confirmed these results. Importantly, this size and clutter information was represented in a way that generalized across different semantic categories. These data provide support for a property-based representation of spaces, distributed across multiple scene-selective regions of the cerebral cortex.

  1. Non-local and nonlinear background suppression method controlled by multi-scale clutter metric

    Science.gov (United States)

    Gong, Jinnan; Hou, Qingyu; Zhang, Wei; Zhi, Xiyang

    2015-07-01

    To improve the detection performance for non-morphological multi-scale target in IR image containing complex cloud clutter, on basis of cloud scenario self-similarity feature, a non-local and nonlinear background suppression algorithm controlled by multi-scale clutter metric is presented. According to the classical achievements on cloud structure, self-similarity and relativity of cloud clutter on image for target detection is deeply analyzed by classical indicators firstly. Then we establish multi-scale clutter metric method based on LoG operator to describe scenes feature for controlled suppression method. After that, non-local means based on optimal strength similarity metric as non-local processing, and multi-scale median filter and on minimum gradient direction as local processing are set up. Finally linear fusing principle adopting clutter metric for local and non-local processing is put forward. Experimental results by two kinds of infrared imageries show that compared with classical and similar methods, the proposed method solves the existing problems of targets energy attenuation and suppression degradation in strongly evolving regions in previous methods. By evaluating indicators, the proposed method has a superior background suppression performance by increasing the BSF and ISCR 2 times at least.

  2. Intra-Abdominal Hypertension and Abdominal Compartment Syndrome after Abdominal Wall Reconstruction: Quaternary Syndromes?

    Science.gov (United States)

    Kirkpatrick, A W; Nickerson, D; Roberts, D J; Rosen, M J; McBeth, P B; Petro, C C; Berrevoet, Frederik; Sugrue, M; Xiao, Jimmy; Ball, C G

    2017-06-01

    Reconstruction with reconstitution of the container function of the abdominal compartment is increasingly being performed in patients with massive ventral hernia previously deemed inoperable. This situation places patients at great risk of severe intra-abdominal hypertension and abdominal compartment syndrome if organ failure ensues. Intra-abdominal hypertension and especially abdominal compartment syndrome may be devastating systemic complications with systematic and progressive organ failure and death. We thus reviewed the pathophysiology and reported clinical experiences with abnormalities of intra-abdominal pressure in the context of abdominal wall reconstruction. Bibliographic databases (1950-2015), websites, textbooks, and the bibliographies of previously recovered articles for reports or data relating to intra-abdominal pressure, intra-abdominal hypertension, and the abdominal compartment syndrome in relation to ventral, incisional, or abdominal hernia repair or abdominal wall reconstruction. Surgeons should thus consider and carefully measure intra-abdominal pressure and its resultant effects on respiratory parameters and function during abdominal wall reconstruction. The intra-abdominal pressure post-operatively will be a result of the new intra-peritoneal volume and the abdominal wall compliance. Strategies surgeons may utilize to ameliorate intra-abdominal pressure rise after abdominal wall reconstruction including temporizing paralysis of the musculature either temporarily or semi-permanently, pre-operative progressive pneumoperitoneum, permanently removing visceral contents, or surgically releasing the musculature to increase the abdominal container volume. In patients without complicating shock and inflammation, and in whom the abdominal wall anatomy has been so functionally adapted to maximize compliance, intra-abdominal hypertension may be transient and tolerable. Intra-abdominal hypertension/abdominal compartment syndrome in the specific setting of

  3. Recurrent Abdominal Pain

    Science.gov (United States)

    Banez, Gerard A.; Gallagher, Heather M.

    2006-01-01

    The purpose of this article is to provide an empirically informed but clinically oriented overview of behavioral treatment of recurrent abdominal pain. The epidemiology and scope of recurrent abdominal pain are presented. Referral process and procedures are discussed, and standardized approaches to assessment are summarized. Treatment protocols…

  4. [Abdominal pregnancy, institutional experience].

    Science.gov (United States)

    Bonfante Ramírez, E; Bolaños Ancona, R; Simón Pereyra, L; Juárez García, L; García-Benitez, C Q

    1998-07-01

    Abdominal pregnancy is a rare entity, which has been classified as primary or secondary by Studiford criteria. A retrospective study, between January 1989 and December 1994, realized at Instituto Nacional de Perinatología, found 35,080 pregnancies, from which 149 happened to be ectopic, and 6 of them were abdominal. All patients belonged to a low income society class, age between 24 and 35 years, and average of gestations in 2.6. Gestational age varied from 15 weeks to 32.2 weeks having only one delivery at term with satisfactory postnatal evolution. One patient had a recurrent abdominal pregnancy, with genital Tb as a conditional factor. Time of hospitalization varied from 4 to 5 days, and no further patient complications were reported. Fetal loss was estimated in 83.4%. Abdominal pregnancy is often the sequence of a tubarian ectopic pregnancy an when present, it has a very high maternal mortality reported in world literature, not found in this study. The stated frequency of abdominal pregnancy is from 1 of each 3372, up to 1 in every 10,200 deliveries, reporting in the study 1 abdominal pregnancy in 5846 deliveries. The study had two characteristic entities one, the recurrence and two, the delivery at term of one newborn. Abdominal pregnancy accounts for 4% of all ectopic pregnancies. Clinical findings in abdominal pregnancies are pain, transvaginal bleeding and amenorrea, being the cardinal signs of ectopic pregnancy.

  5. Abdominal hernias: Radiological features

    Science.gov (United States)

    Lassandro, Francesco; Iasiello, Francesca; Pizza, Nunzia Luisa; Valente, Tullio; Stefano, Maria Luisa Mangoni di Santo; Grassi, Roberto; Muto, Roberto

    2011-01-01

    Abdominal wall hernias are common diseases of the abdomen with a global incidence approximately 4%-5%. They are distinguished in external, diaphragmatic and internal hernias on the basis of their localisation. Groin hernias are the most common with a prevalence of 75%, followed by femoral (15%) and umbilical (8%). There is a higher prevalence in males (M:F, 8:1). Diagnosis is usually made on physical examination. However, clinical diagnosis may be difficult, especially in patients with obesity, pain or abdominal wall scarring. In these cases, abdominal imaging may be the first clue to the correct diagnosis and to confirm suspected complications. Different imaging modalities are used: conventional radiographs or barium studies, ultrasonography and Computed Tomography. Imaging modalities can aid in the differential diagnosis of palpable abdominal wall masses and can help to define hernial contents such as fatty tissue, bowel, other organs or fluid. This work focuses on the main radiological findings of abdominal herniations. PMID:21860678

  6. Gastrointestinal causes of abdominal pain.

    Science.gov (United States)

    Marsicano, Elizabeth; Vuong, Giao Michael; Prather, Charlene M

    2014-09-01

    Gastrointestinal causes of abdominal pain are numerous. These causes are reviewed in brief here, divided into 2 categories: acute abdominal pain and chronic abdominal pain. They are further subcategorized by location of pain as it pertains to the abdomen.

  7. Using particle filter to track horizontal variations of atmospheric duct structure from radar sea clutter

    Directory of Open Access Journals (Sweden)

    X. F. Zhao

    2012-08-01

    Full Text Available This paper addresses the problem of estimating range-varying parameters of the height-dependent refractivity over the sea surface from radar sea clutter. In the forward simulation, the split-step Fourier parabolic equation (PE is used to compute the radar clutter power in the complex refractive environments. Making use of the inherent Markovian structure of the split-step Fourier PE solution, the refractivity from clutter (RFC problem is formulated within a nonlinear recursive Bayesian state estimation framework. Particle filter (PF that is a technique for implementing a recursive Bayesian filter by Monte Carlo simulations is used to track range-varying characteristics of the refractivity profiles. Basic ideas of employing PF to solve RFC problem are introduced. Both simulation and real data results are presented to check up the feasibility of PF-RFC performances.

  8. Comparative analysis of clutter suppression techniques for landmine detection using ground-penetrating radar

    Science.gov (United States)

    Yoldemir, Ahmet Burak; Gürcan, Rıdvan; Kaplan, Gülay Büyükaksoy; Sezgin, Mehmet

    2011-06-01

    In this study, we provide an extensive comparison of different clutter suppression techniques that are proposed to enhance ground penetrating radar (GPR) data. Unlike previous studies, we directly measure and present the effect of these preprocessing algorithms on the detection performance. Basic linear prediction algorithm is selected as the detection scheme and it is applied to real GPR data after applying each of the available clutter suppression techniques. All methods are tested on an extensive data set of different surrogate mines and other objects that are commonly encountered under the ground. Among several algorithms, singular value decomposition based clutter suppression stands out with its superior performance and low computational cost, which makes it practical to use in real-time applications.

  9. Statistical-physical model for foliage clutter in ultra-wideband synthetic aperture radar images.

    Science.gov (United States)

    Banerjee, Amit; Chellappa, Rama

    2003-01-01

    Analyzing foliage-penetrating (FOPEN) ultra-wideband synthetic aperture radar (SAR) images is a challenging problem owing to the noisy and impulsive nature of foliage clutter. Indeed, many target-detection algorithms for FOPEN SAR data are characterized by high false-alarm rates. In this work, a statistical-physical model for foliage clutter is proposed that explains the presence of outliers in the data and suggests the use of symmetric alpha-stable (SalphaS) distributions for accurate clutter modeling. Furthermore, with the use of general assumptions of the noise sources and propagation conditions, the proposed model relates the parameters of the SalphaS model to physical parameters such as the attenuation coefficient and foliage density.

  10. Impact of atmospheric clutter on Doppler-limited gas sensors in the submillimeter/terahertz.

    Science.gov (United States)

    Medvedev, Ivan R; Neese, Christopher F; Plummer, Grant M; De Lucia, Frank C

    2011-06-20

    It is well known that clutter (spectral interference) from atmospheric constituents can be a severe limit for spectroscopic point sensors, especially where high sensitivity and specificity are required. In this paper, we will show for submillimeter/terahertz (SMM/THz) sensors that use cw electronic techniques the clutter limit for the detection of common target gases with absolute specificity (probability of false alarm ≪ 10⁻¹⁰) is in the ppt (1 part in 10¹²) range or lower. This is because the most abundant atmospheric gases are either transparent to SMM/THz radiation (e.g., CO₂) or have spectra that are very sparse relative to the 10⁵ Doppler-limited resolution elements available (e.g., H₂O). Moreover, the low clutter limit demonstrated for cw electronic systems in the SMM/THz is independent of system size and complexity.

  11. Simulation and Prediction of Weather Radar Clutter Using a Wave Propagator on High Resolution NWP Data

    DEFF Research Database (Denmark)

    Benzon, Hans-Henrik; Bovith, Thomas

    2008-01-01

    for prediction of this type of weather radar clutter is presented. The method uses a wave propagator to identify areas of potential non-standard propagation. The wave propagator uses a three dimensional refractivity field derived from the geophysical parameters: temperature, humidity, and pressure obtained from...... a high-resolution Numerical Weather Prediction (NWP) model. The wave propagator is based on the parabolic equation approximation to the electromagnetic wave equation. The parabolic equation is solved using the well-known Fourier split-step method. Finally, the radar clutter prediction technique is used......Weather radars are essential sensors for observation of precipitation in the troposphere and play a major part in weather forecasting and hydrological modelling. Clutter caused by non-standard wave propagation is a common problem in weather radar applications, and in this paper a method...

  12. Pulmonary complications of upper abdominal surgery.

    Directory of Open Access Journals (Sweden)

    Deodhar S

    1991-04-01

    Full Text Available Pulmonary complications encountered in 67 patients undergoing upper abdominal surgery in our unit in one year period are analysed. Pulmonary function tests and their post-operative reduction, as also the risk factors are discussed. Pathophysiology responsible for pulmonary complications is outlined.

  13. Plaster body wrap: effects on abdominal fat.

    Science.gov (United States)

    Santos Moreira, Juliana; Melo, Ana Sofia Carneiro Pinto de; Noites, Andreia; Couto, Miriam Faria; Melo, Cristina Argel de; Adubeiro, Nuno Carvalho Freire de Almeida

    2013-12-01

    Abdominal fat is associated with metabolic disorders, leading to cardiovascular risk factors and numerous diseases. This study aimed to analyze the effect of plaster body wrap in combination with aerobic exercise on abdominal fat. Nineteen female volunteers were randomly divided into intervention group (IG; n = 10) performing aerobic exercise with plaster body wrap, and control group (CG; n = 9) performing only exercise. Subcutaneous and visceral fat were measured using ultrasound; subcutaneous fat was also estimated on analysis of skinfolds and abdominal perimeters. At the end of the 10-sessions protocol, the IG demonstrated a significant decrease (p ≤ 0.05) in subcutaneous fat at the left anterior superior iliac spine (ASIS) level and in iliac crest perimeter measurements. A large intervention effect size strength (0.80) was found in subcutaneous fat below the navel and a moderate effect size strength on the vertical abdominal skinfold (0.62) and the perimeter of the most prominent abdominal point (0.57). Comparing the initial and final data of each group, the IG showed a significant decrease in numerous variables including visceral and subcutaneous fat above and below the navel measured by ultrasound (p ≤ 0.05). Plaster body wrap in combination with aerobic exercise seems to be effective for abdominal fat reduction.

  14. Visual Multi-Object Tracking in the Presence of Cluttered Scenes

    Directory of Open Access Journals (Sweden)

    Xu-Sheng Gan

    2013-07-01

    Full Text Available The aim of this study was to investigate the visual multi-object tracking in the presence of cluttered scenes. A improved algorithm of fusing multi-source information including location and color evidences were introduced based on Dezert-Smarandache Theory (DSmT and Particle Filters (PF. Results showed that the conflict strategy and DSmT combination model were available and the proposed approach exhibited a significantly better performance for dealing with high conflict between evidences than a conventional PF. The suggested approach can easily be generalized to deal with larger number of visual multi-object and additional cues in the presence of cluttered scenes.

  15. Direction-of-Arrival Estimation for Radar Ice Sounding Surface Clutter Suppression

    DEFF Research Database (Denmark)

    Nielsen, Ulrik; Dall, Jørgen

    2015-01-01

    Ice sounding radars are able to measure ice sheets by profiling their glaciological features from the surface to the bedrock. The current airborne and, in particular, future space-based systems are suffering from off-nadir surface clutter, which can mask the depth signal of interest. The most...... estimation for surface clutter signals, which includes a formulation of the mathematical foundation of spatial aliasing. DOA estimation is applied to data acquired with the P-band POLarimetric Airborne Radar Ice Sounder at the Jutulstraumen Glacier, Antarctica. The effects of spatial aliasing related...

  16. Numerical simulation of radar surveillance for the ship target in oceanic clutters

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A fast iterative approach of generalized forward-backward method with the spectrum acceleration algorithm (GFBM/SAA) is developed for solving electromagnetic field integral equation and is applied to numerical simulation of radar surveillance of the ship target in oceanic clutters. Randomly rough surface is realized by the Monte Carlo method using the Pierson-Moskowitz spectrum. Numerical results of bistatic and back-scattering from the ship target and oceanic clutters demonstrate the functional dependencies upon the situation of radar surveillance such as the incidence and observation angles, radar altitude, ship RCS and other oceanic conditions.

  17. [Inflammatory abdominal aortic aneurysm].

    Science.gov (United States)

    Ziaja, K; Sedlak, L; Urbanek, T; Kostyra, J; Ludyga, T

    2000-01-01

    The reported incidence of inflammatory abdominal aortic aneurysm (IAAA) is from 2% to 14% of patients with abdominal aortic aneurysm and the etiology of this disease is still discussed--according to the literature several pathogenic theories have been proposed. From 1992 to 1997 32 patients with IAAA were operated on. The patients were mostly symptomatic--abdominal pain was present in 68.75% cases, back pain in 31.25%, fever in 12.5% and weight loss in 6.25% of the operated patients. In all the patients ultrasound examination was performed, in 4 patients CT and in 3 cases urography. All the patients were operated on and characteristic signs of inflammatory abdominal aortic aneurysm like: thickened aortic wall, perianeurysmal infiltration or retroperitoneal fibrosis with involvement of retroperitoneal structures were found. In all cases surgery was performed using transperitoneal approach; in three cases intraoperatively contiguous abdominal organs were injured, which was connected with their involvement into periaortic inflammation. In 4 cases clamping of the aorta was done at the level of the diaphragmatic hiatus. 3 patients (9.37%) died (one patient with ruptured abdominal aortic aneurysm). Authors present diagnostic procedures and the differences in the surgical tactic, emphasizing the necessity of the surgical therapy in patients with inflammatory abdominal aortic aneurysm.

  18. Detection of Aircraft Embedded in Ground Clutter by Means of Non-Doppler X-band Radar

    Science.gov (United States)

    Hwang, Seongin; Ishii, Seishiro; Sayama, Shuji; Sekine, Matsuo

    It is reported that various radar clutter obey a Weibull distribution under certain conditions. To suppress such Weibull-distributed clutter, a new adaptive method was proposed by the present author. In this method, the parameters of the Weibull distribution and the threshold level for an adaptive Constant False Alarm Rate (CFAR) detector are determined by calculating the variance before it passes through a logarithmic amplifier. To apply this new method to practical problems observed by an X-band radar, a computer simulation are made for a finite number of samples in order to obtain the CFAR maintenance in Weibull radar clutter. Finally an improvement value of target-to-clutter ratio 30.07 dB was obtained for the detection of an aircraft embedded in ground clutter.

  19. Analysis of Geosynchronous Satellite-air Bistatic SAR Clutter Characteristics from the Point of View of Ground Moving Target Indication

    Directory of Open Access Journals (Sweden)

    Zhang Dan-dan

    2013-09-01

    Full Text Available Under the geometry of geosynchronous satellite-air bistatic SAR where the geosynchronous satellite is the transmitter and aerostat is the receiver, in order to suppress clutter and detect slowly moving target using Space Time Adaptive Processing (STAP, it is necessary to analyze the clutter characteristics. From the point of view of ground moving target indication, the theory model of the clutter characteristics under the geometry of geosynchronous satellite-space bistatic SAR is analyzed and established in this paper; especially, the range-dependence characteristics of the angle-Doppler curve of the clutter is analyzed. Finally, the simulation verifies correctness of the analysis. The theory model and the conclusion in this paper indicates the clutter characteristics of the new geosynchronous satellite-air bistatic SAR mode, and provide theory basis for the selection and research of ground moving target indication method under this mode.

  20. Wall Clutter Mitigation in Through-the-Wall Imaging Radar with Sparse Array Antenna Based on Independent Component Analysis

    Directory of Open Access Journals (Sweden)

    Zhang Chi

    2014-10-01

    Full Text Available For Through-the-Wall Imaging Radar (TWIR, wall clutter is critical for detecting target signals behind a wall. For a system with a sparse antenna array, the lack of observation channels makes it more difficult to separate the target signals and wall clutter. On the basis of fluctuation of the range profile in real transmit/receive channels, this paper proposes to use Independent Component Analysis (ICA on multiple down-range observations of each transmit/receive channel to remove the wall clutter. The simulation and experimental results show that the proposed method effectively separate target and clutter components, even though the signal-to-clutter ratio is only -30 dB.

  1. Congenital Abdominal Wall Defects

    DEFF Research Database (Denmark)

    Risby, Kirsten; Jakobsen, Marianne Skytte; Qvist, Niels

    2016-01-01

    complications were seen in five (15%) children: four had detachment of the mesh and one patient developed abdominal compartment syndrome. Mesh related clinical infection was observed in five children. In hospital mortality occurred in four cases (2 gastroschisis and 2 omphalocele) and was not procedure......OBJECTIVE: To evaluate the clinical utility of GORE® DUALMESH (GDM) in the staged closure of large congenital abdominal wall defects. MATERIALS AND METHODS: Data of patients with congenital abdominal wall defects managed with GDM was analyzed for outcome regarding complete fascial closure; mesh...

  2. Abdominal wall endometriosis.

    Science.gov (United States)

    Upadhyaya, P; Karak, A K; Sinha, A K; Kumar, B; Karki, S; Agarwal, C S

    2010-01-01

    Endometriosis of abdominal wall scar following operation on uterus and tubes is extremely rare. The late onset of symptoms after surgery is the usual cause of misdiagnosis. Scar endometriosis is a rare disease which is difficult to diagnose and should always be considered as a differential diagnosis of painful abdominal masses in women. The diagnosis is made only after excision and histopathology of the lesion. Preoperative differentials include hernia, lipoma, suture granuloma or abscess. Hence an awareness of the entity avoids delay in diagnosis, helps clinicians to a more tailored treatment and also avoids unnecessary referrals. We report a case of abdominal endometriosis. The definitive diagnosis of which was established by histopathological studies.

  3. Advancement of High Resolution Radar Polarimetry in Target Verses Clutter Detection, Discrimination, Classification: A. Basic Theory and Modeling of Polarimetric Clutter Phenomenology.

    Science.gov (United States)

    1988-07-15

    Humboldt award, and another 15,000 km by train (during the tough winter months 1987 Jan.-March) and airplane (from Noordkap to Lisbon, from Weston -Super...polarLmetry to target/clutter analysis was recognized Kannen (11 with deletions and addition to meet his- long ago. w. also note here that Copeland (1960...8217. 1960 Copeland classifies (syimnetrical) radar 1975 Poelman reports on using orthoonally targets by polarization properties. polarized returns to detect

  4. Abdominal tuberculosis: Imaging features

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Jose M. [Department of Radiology, Hospital de S. Joao, Porto (Portugal)]. E-mail: jmpjesus@yahoo.com; Madureira, Antonio J. [Department of Radiology, Hospital de S. Joao, Porto (Portugal); Vieira, Alberto [Department of Radiology, Hospital de S. Joao, Porto (Portugal); Ramos, Isabel [Department of Radiology, Hospital de S. Joao, Porto (Portugal)

    2005-08-01

    Radiological findings of abdominal tuberculosis can mimic those of many different diseases. A high level of suspicion is required, especially in high-risk population. In this article, we will describe barium studies, ultrasound (US) and computed tomography (CT) findings of abdominal tuberculosis (TB), with emphasis in the latest. We will illustrate CT findings that can help in the diagnosis of abdominal tuberculosis and describe imaging features that differentiate it from other inflammatory and neoplastic diseases, particularly lymphoma and Crohn's disease. As tuberculosis can affect any organ in the abdomen, emphasis is placed to ileocecal involvement, lymphadenopathy, peritonitis and solid organ disease (liver, spleen and pancreas). A positive culture or hystologic analysis of biopsy is still required in many patients for definitive diagnosis. Learning objectives:1.To review the relevant pathophysiology of abdominal tuberculosis. 2.Illustrate CT findings that can help in the diagnosis.

  5. [The abdominal catastrophe].

    Science.gov (United States)

    Seiler, Christian A

    2011-08-01

    Patients with an abdominal catastrophe are in urgent need of early, interdisciplinary medical help. The treatment plan should be based on medical priorities and clear leadership. First priority should be given to achieve optimal oxygenation of blood and stabilization of circulation during all treatment-phases. The sicker the patient, the less invasive the (surgical) treatment should to be, which means "damage control only". This short article describes 7 important, pragmatic rules that will help to increase the survival of a patient with an abdominal catastrophe. Preexisting morbidity and risk factors must be included in the overall risk-evaluation for every therapeutic intervention. The challenge in patients with an abdominal catastrophe is to carefully balance the therapeutic stress and the existing resistance of the individual patient. The best way to avoid abdominal disaster, however, is its prevention.

  6. Abdominal and Pelvic CT

    Medline Plus

    Full Text Available ... contrast materials and a metallic taste in your mouth that lasts for at most a minute or ... can diagnose many causes of abdominal pain or injury from trauma with very high accuracy, enabling faster ...

  7. Abdominal x-ray

    Science.gov (United States)

    ... are, or may be, pregnant. Alternative Names Abdominal film; X-ray - abdomen; Flat plate; KUB x-ray ... Assistant Studies, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also ...

  8. Abdominal and Pelvic CT

    Medline Plus

    Full Text Available ... often used to determine the cause of unexplained pain. CT scanning is fast, painless, noninvasive and accurate. ... help diagnose the cause of abdominal or pelvic pain and diseases of the internal organs, small bowel ...

  9. Abdominal and Pelvic CT

    Medline Plus

    Full Text Available ... is done because a potential abnormality needs further evaluation with additional views or a special imaging technique. ... GI) contrast exams and ultrasound are preferred for evaluation of acute abdominal conditions in babies, such as ...

  10. Abdominal ultrasound (image)

    Science.gov (United States)

    Abdominal ultrasound is a scanning technique used to image the interior of the abdomen. Like the X-ray, MRI, ... it has its place as a diagnostic tool. Ultrasound scans use high frequency sound waves to produce ...

  11. Abdominal exploration - slideshow

    Science.gov (United States)

    ... ency/presentations/100049.htm Abdominal exploration - series—Normal anatomy To use the ... Overview The abdomen contains many vital organs: the stomach, the small intestine (jejunum and ileum), the large ...

  12. Abdominal and Pelvic CT

    Medline Plus

    Full Text Available ... is done because a potential abnormality needs further evaluation with additional views or a special imaging technique. ... GI) contrast exams and ultrasound are preferred for evaluation of acute abdominal conditions in babies, such as ...

  13. Linear abdominal trauma.

    Science.gov (United States)

    Danto, L A; Wolfman, E F

    1976-03-01

    Three cases of blunt abdominal trauma are presented to exemplify the mechanism of trauma and the problems of diagnosis associated with any linear blow to the abdomen. The mechanisms of visceral injury are reviewed, and special attention is directed to the abdominal wall injury that can be present in these patients. This injury has special implications in directing the operative approach and repair. An unusual aortic occlusion is described which is peculiar to this type of injury.

  14. Evaluation of plain abdominal radiographs in the diagnosis of abdominal pain.

    Science.gov (United States)

    Eisenberg, R L; Heineken, P; Hedgcock, M W; Federle, M; Goldberg, H I

    1983-04-01

    In an effort to develop referral criteria for the ordering of abdominal radiographs for patients presenting with abdominal symptoms, we prospectively studied the relation between clinical data and radiographic abnormalities. Of 1780 examinations, 179 (10.0%) showed some radiographic abnormality. If abdominal radiographs would have been limited to those patients who had moderate or severe abdominal tenderness, or to patients with a high clinical suspicion of bowel obstruction, renal or ureteral calculi, trauma, ischemia, or gallbladder disease, regardless of the degree of tenderness, 956 (53.7%) examinations would not have been done. All radiographic abnormalities reflecting a serious pathologic process would have been identified. Only 33 (3.5%) abnormalities of limited significance, almost all localized or generalized ileus, would have been undetected. The adoption of these referral criteria would result in minimal loss of clinically useful information, large financial savings, and a reduction in radiation exposure.

  15. Ventral Abdominal Hernia

    Directory of Open Access Journals (Sweden)

    Georgi Tchernev

    2017-08-01

    Full Text Available A 63-year-old Caucasian female patient presented with redness of the both foot and lower legs, as well as edema of the left lower leg, accompanied by subjective complaints of burning. Fever was not reported. Well-circumscribed oval shaped tumor formation was revealed also on the abdominal wall, with hyperpigmented and depigmented areas on its ulcerated surface, measuring approximately 10/10cm in diameter, with soft-elastic texture on palpation.  The lesion occurred in 2011, according to the patient’s history. No subjective complaints were reported in association. The performed ultrasonography revealed intestinal loops in the hernial sac, without incarceration. The diagnosis of ventral abdominal hernia without mechanical ileus was made. The patient was referred for planned surgical procedure, because of her refusal on this stage.The clinical manifestation of the tumor formation on the abdominal wall, required wide spectrum of differential diagnosis, including aneurysm of the abdominal aorta, abdominal tumor, subcutaneous tumor or metastasis or hernia. In the presented cases, the abdominal wall mass was a sporadic clinical finding in the framework of the total-body skin examination in patient with erysipelas. The lack of subjective symptoms, as well as the reported history for hysterectomy and previously abscessus were not enough indicative symptoms for the correct diagnosis. The diagnosis of non-complicated hernia was made via ultrasonography, while the clinical differentiation between hernia and other life-threatening conditions as aneurysms or tumor was not possible.

  16. Realtime generation of K-Distributed sea clutter for hardware in the loop radar evaluation

    CSIR Research Space (South Africa)

    Van der Merwe, Johannes R

    2016-10-01

    Full Text Available This paper proposes a practical implementation for the generation of real-time K-Distributed correlated sea-clutter in firmware. The method uses a dual cumulative distribution function (CDF) based look-up method to transpose a complex uniformly...

  17. Breaking through the clutter : Benefits of advertisement originality and familiarity for brand attention and memory

    NARCIS (Netherlands)

    Pieters, R; Warlop, L; Wedel, M

    2002-01-01

    Rising levels of advertising competition have made it increasingly difficult to attract and hold consumers' attention and to establish strong memory traces for the advertised brand. A common communication strategy to break through this competitive clutter is to increase ad originality However, ad or

  18. Breaking through the Advertising Clutter: A Qualitative Analysis of Broken Stereotypes in Print and Television Advertisements.

    Science.gov (United States)

    Larson, Charles U.

    As a result of the overwhelming amount of print and electronic advertisements which compete for consumer attention, advertisers must find effective methods to get through the ad clutter and capture their audience's interest. Several tactics can accomplish this strategy, including the tactic of breaking or reversing audience expectations or…

  19. Moment-Based Physical Models of Broadband Clutter due to Aggregations of Fish

    Science.gov (United States)

    2013-09-30

    their false alarm rate and latency. Accordingly, a quantitative assesment has begun of the temporal persistence of the observed fish-clutter echoes...Assessment of the Pacific Sardine Resource in 2012 for U.S. Management in 2013,” Pacific Fishery Management Council November 2012 Briefing Book

  20. An Improved Clutter Suppression Method for Weather Radars Using Multiple Pulse Repetition Time Technique

    Directory of Open Access Journals (Sweden)

    Yingjie Yu

    2017-01-01

    Full Text Available This paper describes the implementation of an improved clutter suppression method for the multiple pulse repetition time (PRT technique based on simulated radar data. The suppression method is constructed using maximum likelihood methodology in time domain and is called parametric time domain method (PTDM. The procedure relies on the assumption that precipitation and clutter signal spectra follow a Gaussian functional form. The multiple interleaved pulse repetition frequencies (PRFs that are used in this work are set to four PRFs (952, 833, 667, and 513 Hz. Based on radar simulation, it is shown that the new method can provide accurate retrieval of Doppler velocity even in the case of strong clutter contamination. The obtained velocity is nearly unbiased for all the range of Nyquist velocity interval. Also, the performance of the method is illustrated on simulated radar data for plan position indicator (PPI scan. Compared with staggered 2-PRT transmission schemes with PTDM, the proposed method presents better estimation accuracy under certain clutter situations.

  1. Surface return direction-of-arrival analysis for radar ice sounding surface clutter suppression

    DEFF Research Database (Denmark)

    Nielsen, Ulrik; Dall, Jørgen

    2015-01-01

    with coherent signal processing techniques can improve the suppression, in particular if the direction of arrival (DOA) of the clutter signal is estimated accurately. This paper deals with data-driven DOA estimation. By using P-band data from the ice shelf in Antarctica it is demonstrated that a varying...... penetration depth influences the DOA....

  2. A single-ensemble-based hybrid approach to clutter rejection combining bilinear Hankel with regression.

    Science.gov (United States)

    Shen, Zhiyuan; Feng, Naizhang; Lee, Chin-Hui

    2013-04-01

    Clutter regarded as ultrasound Doppler echoes of soft tissue interferes with the primary objective of color flow imaging (CFI): measurement and display of blood flow. Multi-ensemble samples based clutter filters degrade resolution or frame rate of CFI. The prevalent single-ensemble clutter rejection filter is based on a single rejection criterion and fails to achieve a high accuracy for estimating both the low- and high-velocity blood flow components. The Bilinear Hankel-SVD achieved more exact signal decomposition than the conventional Hankel-SVD. Furthermore, the correlation between two arbitrary eigen-components obtained by the B-Hankel-SVD was demonstrated. In the hybrid approach, the input ultrasound Doppler signal first passes through a low-order regression filter, and then the output is properly decomposed into a collection of eigen-components under the framework of B-Hankel-SVD. The blood flow components are finally extracted based on a frequency threshold. In a series of simulations, the proposed B-Hankel-SVD filter reduced the estimation bias of the blood flow over the conventional Hankel-SVD filter. The hybrid algorithm was shown to be more effective than regression or Hankel-SVD filters alone in rejecting the undesirable clutter components with single-ensemble (S-E) samples. It achieved a significant improvement in blood flow frequency estimation and estimation variance over the other competing filters.

  3. Breaking through the clutter : Benefits of advertisement originality and familiarity for brand attention and memory

    NARCIS (Netherlands)

    Pieters, R; Warlop, L; Wedel, M

    2002-01-01

    Rising levels of advertising competition have made it increasingly difficult to attract and hold consumers' attention and to establish strong memory traces for the advertised brand. A common communication strategy to break through this competitive clutter is to increase ad originality However, ad or

  4. Exponential Decay in Windblown Radar Ground Clutter Doppler Spectra: Multifrequency Measurements and Model.

    Science.gov (United States)

    2007-11-02

    Reese Straw, William Dustin, Carol Bernhard, Joanne Bradley and Bob Graham-Munn. The manuscript was skillfully prepared by Pat DeCuir and kindly and...spreading of Ot° rees in Doppler, i.e., j^Krees’ Pto^dv = °trees- so Krees’ Ptot^ represents the normalized density of windblown tree clutter power

  5. Detection of dim point targets in cluttered maritime backgrounds through multisensor image fusion

    NARCIS (Netherlands)

    Toet, A.

    2002-01-01

    Multispectral IR imaging techniques are frequently deployed in maritime operations, for instance to detect floating mines or to find small dinghies and swimmers during search and rescue operations. However, maritime backgrounds usually contain a large amount of clutter that severely hampers the

  6. Detection of dim point targets in cluttered maritime backgrounds through multisensor image fusion

    NARCIS (Netherlands)

    Toet, A.

    2002-01-01

    Multispectral IR imaging techniques are frequently deployed in maritime operations, for instance to detect floating mines or to find small dinghies and swimmers during search and rescue operations. However, maritime backgrounds usually contain a large amount of clutter that severely hampers the dete

  7. Breaking through the clutter : Benefits of advertisement originality and familiarity for brand attention and memory

    NARCIS (Netherlands)

    Pieters, R; Warlop, L; Wedel, M

    Rising levels of advertising competition have made it increasingly difficult to attract and hold consumers' attention and to establish strong memory traces for the advertised brand. A common communication strategy to break through this competitive clutter is to increase ad originality However, ad

  8. EMI obscuration of buried UXO by geophysical magnetic permeability, anthropogenic clutter, and by magnitude disparities

    Science.gov (United States)

    O'Neill, K.; Shubitidze, F.; Sun, K.; Shamatava, I.; Paulsen, K.

    2005-05-01

    For UWB (30 Hz - 100 kHz) electromagnetic induction (EMI) sensor discrimination of unexploded ordnance (UXO), we evaluate first the effects of significant magnetic permeability in the surrounding soil. Measured data and theoretical arguments suggest that ground effects can often be accounted for by using a simple halfspace analytical solution. Thus, when target responses are strong enough, free-space target signature shapes can still be used for discrimination if properly compensated. At the same time, even in artificially well-mixed, physically smoothed settings, local variations in soil permeability can be a significant source of signal clutter. Cases with multiple UXO"s beneath dispersed small metallic clutter are also considered as instances in which clutter may dominate. In simulations of two comparably sized UXO"s at comparable depths with a signal to clutter ratio (SCR) of ~ 20, UWB data distinguishes the two objects reliably over a ground surface measurement grid. For similar cases but with the objects at significantly different depths relative to one another, one cannot distinguish the deeper target, even with the same noise level and with UWB data. Measurements illustrate the level of EMI SCR to be expected from dispersed small metallic items collected from a firing range. For cases with a single piece of clutter and a much more massive UXO immediately below, simulations show almost complete obscuration of the UXO, in both frequency and time domains. This is not caused by signal blockage but results from different degrees of proximity to the sensor, i.e. from the consequent signal magnitude disparity.

  9. Abdominal emergencies in pediatrics.

    Science.gov (United States)

    Coca Robinot, D; Liébana de Rojas, C; Aguirre Pascual, E

    2016-05-01

    Abdominal symptoms are among the most common reasons for pediatric emergency department visits, and abdominal pain is the most frequently reported symptom. Thorough history taking and physical examination can often reach the correct diagnosis. Knowing the abdominal conditions that are most common in each age group can help radiologists narrow the differential diagnosis. When imaging tests are indicated, ultrasonography is usually the first-line technique, enabling the diagnosis or adding relevant information with the well-known advantages of this technique. Nowadays, plain-film X-ray studies are reserved for cases in which perforation, bowel obstruction, or foreign body ingestion is suspected. It is also important to remember that abdominal pain can also occur secondary to basal pneumonia. CT is reserved for specific indications and in individual cases, for example, in patients with high clinical suspicion of abdominal disease and inconclusive findings at ultrasonography. We review some of the most common conditions in pediatric emergencies, the different imaging tests indicated in each case, and the imaging signs in each condition.

  10. Abdominal paracentesis and thoracocentesis.

    Science.gov (United States)

    Lee, Ser Yee; Pormento, James G; Koong, Heng Nung

    2009-04-01

    Abdominal paracentesis and thoracocentesis are common bedside procedures with diagnostic, therapeutic and palliative roles. We describe a useful and familiar a useful and familiar technique with the use of a multiple lumen catheter commonly used for central venous line insertion for drainage of ascites or moderate to large pleural effusions. The use of a multiple lumen catheter allows easier and more rapid aspiration of fluid with a smaller probability of the side holes being blocked as compared to the standard needle or single catheter methods. This is particularly useful in situations where the dedicated commercial kits for thoracocentesis and abdominal paracentesis are not readily available.

  11. Childhood abdominal cystic lymphangioma

    Energy Technology Data Exchange (ETDEWEB)

    Konen, Osnat; Rathaus, Valeria; Shapiro, Myra [Department of Diagnostic Imaging, Meir General Hospital, Sapir Medical Centre, Kfar Saba (Israel); Dlugy, Elena [Department of Paediatric Surgery, Schneider Medical Centre, Sackler School of Medicine, Tel-Aviv University (Israel); Freud, Enrique [Department of Paediatric Surgery, Sapir Medical Centre, Sackler School of Medicine, Tel-Aviv University (Israel); Kessler, Ada [Department of Diagnostic Imaging, Sourasky Medical Centre, Tel-Aviv (Israel); Horev, Gadi [Department of Diagnostic Imaging, Schneider Medical Centre, Tel-Aviv (Israel)

    2002-02-01

    Background: Abdominal lymphangioma is a rare benign congenital malformation of the mesenteric and/or retroperitoneal lymphatics. Clinical presentation is variable and may be misleading; therefore, complex imaging studies are necessary in the evaluation of this condition. US and CT have a major role in the correct preoperative diagnosis and provide important information regarding location, size, adjacent organ involvement, and expected complications. Objective: To evaluate the clinical and imaging findings of seven children with proven abdominal cystic lymphangioma. Materials and methods: Clinical and imaging files of seven children with pathologically proven abdominal lymphangioma, from three university hospitals, were retrospectively evaluated. Patient's ages ranged from 1 day to 6 years (mean, 2.2 years). Symptoms and signs included evidence of inflammation, abnormal prenatal US findings, chronic abdominal pain, haemorrhage following trauma, clinical signs of intestinal obstruction, and abdominal distension with lower extremities lymphoedema. Plain films of five patients, US of six patients and CT of five patients were reviewed. Sequential imaging examinations were available in two cases. Results: Abdominal plain films showed displacement of bowel loops by a soft tissue mass in five of six patients, two of them with dilatation of small bowel loops. US revealed an abdominal multiloculated septated cystic mass in five of six cases and a single pelvic cyst in one which changed in appearance over 2 months. Ascites was present in three cases. CT demonstrated a septated cystic mass of variable sizes in all available five cases. Sequential US and CT examinations in two patients showed progressive enlargement of the masses, increase of fluid echogenicity, and thickening of walls or septa in both cases, with multiplication of septa in one case. At surgery, mesenteric lymphangioma was found in five patients and retroperitoneal lymphangioma in the other two

  12. [Abdominal actinomycosis with IUD].

    Science.gov (United States)

    Kamprath, S; Merker, A; Kühne-Heid, R; Schneider, A

    1997-01-01

    We report a case of abdominal actinomycosis in a 54 year old woman using an intrauterine device for a period of 8 years. The most important finding was a tuboovarialabscess at the left pelvic side with involvement of the serosa of the jejunum, ileum, sigma, and omentum majus. Intraoperative exploration showed a solid retroperitoneal infiltration between the pelvic side wall and sigma. Another infiltration was found on the left side of the abdominal wall. The diagnosis was confirmed by histopathological examination and the patient was treated by a combination of Aminopenicillin and Metronidazol. After a period of three months we observed a complete regression of the clinical and the MRI findings.

  13. Heritability and Genetic Relationship of Adult Self-Reported Stuttering, Cluttering and Childhood Speech-Language Disorders

    DEFF Research Database (Denmark)

    Fagnani, Corrado; Fibiger, Steen; Skytthe, Axel;

    2011-01-01

    Genetic influence and mutual genetic relationship for adult self-reported childhood speech-language disorders, stuttering, and cluttering were studied. Using nationwide questionnaire answers from 34,944 adult Danish twins, a multivariate biometric analysis based on the liability-threshold model......, 0.78/0.80 for stuttering, and 0.53/0.65 for cluttering. For each trait, the same genes were suggested to affect liability in males and females. Furthermore, high genetic correlations between the traits were obtained; the estimates for childhood speech-language disorders and stuttering were 0.......71/0.79 for males/females, for childhood speech-language disorders and cluttering 0.73/0.56, and for stuttering and cluttering 0.53/0.57. Substantial unique environmental correlations between the traits were also found in both genders. Conclusion: With the limitations related to self-reporting from adult age...

  14. Detection of Ground Clutter from Weather Radar Using a Dual-Polarization and Dual-Scan Method

    Directory of Open Access Journals (Sweden)

    Mohammad-Hossein Golbon-Haghighi

    2016-06-01

    Full Text Available A novel dual-polarization and dual-scan (DPDS classification algorithm is developed for clutter detection in weather radar observations. Two consecutive scans of dual-polarization radar echoes are jointly processed to estimate auto- and cross-correlation functions. Discriminants are then defined and estimated in order to separate clutter from weather based on their physical and statistical properties. An optimal Bayesian classifier is used to make a decision on clutter presence from the estimated discriminant functions. The DPDS algorithm is applied to the data collected with the KOUN polarimetric radar and compared with the existing detection methods. It is shown that the DPDS algorithm yields a higher probability of detection and lower false alarm rate in clutter detection.

  15. Adult abdominal hernias.

    LENUS (Irish Health Repository)

    Murphy, Kevin P

    2014-06-01

    Educational Objectives and Key Points. 1. Given that abdominal hernias are a frequent imaging finding, radiologists not only are required to interpret the appearances of abdominal hernias but also should be comfortable with identifying associated complications and postrepair findings. 2. CT is the imaging modality of choice for the assessment of a known adult abdominal hernia in both elective and acute circumstances because of rapid acquisition, capability of multiplanar reconstruction, good spatial resolution, and anatomic depiction with excellent sensitivity for most complications. 3. Ultrasound is useful for adult groin assessment and is the imaging modality of choice for pediatric abdominal wall hernia assessment, whereas MRI is beneficial when there is reasonable concern that a patient\\'s symptoms could be attributable to a hernia or a musculoskeletal source. 4. Fluoroscopic herniography is a sensitive radiologic investigation for patients with groin pain in whom a hernia is suspected but in whom a hernia cannot be identified at physical examination. 5. The diagnosis of an internal hernia not only is a challenging clinical diagnosis but also can be difficult to diagnose with imaging: Closed-loop small-bowel obstruction and abnormally located bowel loops relative to normally located small bowel or colon should prompt assessment for an internal hernia.

  16. Abdominal and Pelvic CT

    Medline Plus

    Full Text Available ... as ulcerative colitis or Crohn's disease , pancreatitis or liver cirrhosis. cancers of the liver, kidneys, pancreas, ovaries and bladder as well as ... injuries to abdominal organs such as the spleen, liver, kidneys or other internal organs in cases of ...

  17. Abdominal and Pelvic CT

    Medline Plus

    Full Text Available ... to help diagnose the cause of abdominal or pelvic pain and diseases of the internal organs, small bowel and colon, such as: infections such as appendicitis , pyelonephritis or infected fluid collections, also known as abscesses. inflammatory bowel disease such as ulcerative colitis or Crohn's ...

  18. Penetrating abdominal trauma

    African Journals Online (AJOL)

    Enrique

    inal trauma (PAT) in our area, and to try to identify a pattern of organ-specific injury ... laparotomy due to persistent abdominal pain, after a period of observation of about .... in the ini- tial assessment who turned out to be free of visceral injuries.

  19. Modeling and Analysis of Target Echo and Clutter in Range-Dependent Bistatic Environments: FY14 Annual Report for ONR

    Science.gov (United States)

    2014-09-30

    Clutter Model: Range-dependent predictions compared with towed array reverberation and clutter data from the Malta Plateau. In Papadakis and Bjørnø...dependent shallow water area. In John S. Papadakis and Leif Bjørnø, editors, 1st Underwater Acoustic Conference and Exhibition: Proceedings, pages 465–472... Papadakis and Leif Bjørnø, editors, 2nd Underwater Acoustic Conference and Exhibition: Proceedings, pages 715–722, 2014. Conference held at Island of

  20. Modeling and Analysis of Target Echo and Clutter in Range-Dependent Bistatic Environments: FY13 Annual Report for ONR

    Science.gov (United States)

    2013-09-30

    to reverberation ratio for isovelocity waveguides related to Weston Memorial Workshop Scenarios A2.I and A2.IV. In John S. Papadakis and Leif...Ell11] Dale D. Ellis. Solutions to range-dependent reverberation and sonar workshop problems using an adiabatic normal mode model. In Papadakis and...DRDC Clutter Model: Range-dependent predictions compared with towed array reverberation and clutter data from the Malta Plateau. In Papadakis and

  1. Children's (Pediatric) Abdominal Ultrasound Imaging

    Medline Plus

    Full Text Available ... are the limitations of Abdominal Ultrasound Imaging? What is Abdominal Ultrasound Imaging? Ultrasound is safe and painless, ... through the blood vessels. top of page How is the procedure performed? For most ultrasound exams, you ...

  2. Children's (Pediatric) Abdominal Ultrasound Imaging

    Medline Plus

    Full Text Available ... particularly valuable for evaluating abdominal, pelvic or scrotal pain in children. Preparation will depend on the type ... help a physician determine the source of abdominal pain, such as gallstones, kidney stones, abscesses or an ...

  3. Children's (Pediatric) Abdominal Ultrasound Imaging

    Medline Plus

    Full Text Available ... or kidneys. top of page What are some common uses of the procedure? Abdominal ultrasound imaging is ... Except for traumatic injury, appendicitis is the most common reason for emergency abdominal surgery. Ultrasound imaging can ...

  4. Screening for Abdominal Aortic Aneurysm

    Science.gov (United States)

    Understanding Task Force Recommendations Screening for Abdominal Aortic Aneurysm The U.S. Preventive Services Task Force (Task Force) has issued a final recommendation statement on Screening for Abdominal Aortic Aneurysm. This final ...

  5. Abdominal aortic aneurysm repair - open

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/007392.htm Abdominal aortic aneurysm repair - open To use the sharing features on this page, please enable JavaScript. Open abdominal aortic aneurysm repair is surgery to fix a widened part ...

  6. An Improved Sequential Initiation Method for Multitarget Track in Clutter with Large Noise Measurement

    Directory of Open Access Journals (Sweden)

    Daxiong Ji

    2014-01-01

    Full Text Available This paper proposes an improved sequential method for underwater multiple objects tracks initiation in clutter, estimating the initial position for the trajectory. The underwater environment is complex and changeable, and the sonar data are not very ideal. When the detection distance is far, the error of measured data is also great. Besides that, the clutter has a grave effect on the tracks initiation. So it is hard to initialize a track and estimate the initial position. The new tracks initiation is that when at least six of ten points meet the requirements, then we determine that there is a new track and the initial states of the parameters are estimated by the linear least square method. Compared to the conventional tracks initiation methods, our method not only considers the kinematics information of targets, but also regards the error of the sonar sensors as an important element. Computer simulations confirm that the performance of our method is very nice.

  7. Clutter and rainfall discrimination by means of doppler-polarimetric measurements and vertical reflectivity profile analysis

    Directory of Open Access Journals (Sweden)

    F. Silvestro

    2005-01-01

    Full Text Available The estimation of rainfall rate and other parameters from radar scattering volume is heavily affected by the presence of intense sea and ground clutter and echoes which appears in anomalous propagation condition. To deal with these non meteorological echoes we present a new clutter removal algorithm which combines the results of previous works. The algorithm fully exploits both the Doppler and polarimetric capabilities of the radar used and the analysis of vertical reflectivity profile in order to achieve the better identification of the meteorological and non-meteorological targets. The algorithm has been applied to the C-band radar of Monte Settepani (Savona, Italy, which runs in a high-topography environment. Preliminary results are presented.

  8. Adaptive clutter filter in 2-D color flow imaging based on in vivo I/Q signal.

    Science.gov (United States)

    Zhou, Xiaoming; Zhang, Congyao; Liu, Dong C

    2014-01-01

    Color flow imaging has been well applied in clinical diagnosis. For the high quality color flow images, clutter filter is important to separate the Doppler signals from blood and tissue. Traditional clutter filters, such as finite impulse response, infinite impulse response and regression filters, were applied, which are based on the hypothesis that the clutter signal is stationary or tissue moves slowly. However, in realistic clinic color flow imaging, the signals are non-stationary signals because of accelerated moving tissue. For most related papers, simulated RF signals are widely used without in vivo I/Q signal. Hence, in this paper, adaptive polynomial regression filter, which is down mixing with instantaneous clutter frequency, was proposed based on in vivo carotid I/Q signal in realistic color flow imaging. To get the best performance, the optimal polynomial order of polynomial regression filter and the optimal polynomial order for estimation of instantaneous clutter frequency respectively were confirmed. Finally, compared with the mean blood velocity and quality of 2-D color flow image, the experiment results show that adaptive polynomial regression filter, which is down mixing with instantaneous clutter frequency, can significantly enhance the mean blood velocity and get high quality 2-D color flow image.

  9. Cognitive software defined radar: waveform design for clutter and interference suppression

    Science.gov (United States)

    Kirk, Benjamin H.; Owen, Jonathan W.; Narayanan, Ram M.; Blunt, Shannon D.; Martone, Anthony F.; Sherbondy, Kelly D.

    2017-05-01

    Clutter and radio frequency interference (RFI) are prevalent issues in the field of radar and are specifically of interest to of cognitive radar. Here, methods for applying and testing the utility of cognitive radar for clutter and RFI mitigation are explored. Using the adaptable transmit capability, environmental database, and general "awareness" of a cognitive radar system (i.e. spectrum sensing, geographical location, etc.), a matched waveform is synthesized that improves the signal-to-clutter ratio (SCR), assuming at least an estimate of the target response and the environmental clutter response are known a prior i. RFI may also be mitigated by sensing the RF spectrum and adapting the transmit center frequency and bandwidth using methods that optimize bandwidth and signal-to-interference plus noise ratio (SINR) (i.e. the spectrum sensing, multi-objective (SS-MO) algorithm). The improvement is shown by a decrease in the noise floor. The above methods' effectiveness are examined via a test-bed developed around a software defined radio (SDR). Testing and the general use of commercial off the shelf (COTS) devices are desirable for their cost effectiveness, general ease of use, as well as technical and community support, but these devices provide design challenges in order to be effective. The universal software radio peripheral (USRP) X310 SDR is a relatively cheap and portable device that has all the system components of a basic cognitive radar. Design challenges of the SDR include phase coherency between channels, bandwidth limitations, dynamic range, and speed of computation and data communication / recording.

  10. Calculation of Radar Probability of Detection in K-Distributed Sea Clutter and Noise

    Science.gov (United States)

    2011-04-01

    Expanded Swerling Target Models, IEEE Trans. AES 39 (2003) 1059-1069. 18. G. Arfken , Mathematical Methods for Physicists, Second Edition, Academic...form solution for the probability of detection in K-distributed clutter, so numerical methods are required. The K distribution is a compound model...the integration, with the nodes and weights calculated using matrix methods , so that a general purpose numerical integration routine is not required

  11. A GPU-Parallelized Eigen-Based Clutter Filter Framework for Ultrasound Color Flow Imaging.

    Science.gov (United States)

    Chee, Adrian J Y; Yiu, Billy Y S; Yu, Alfred C H

    2017-01-01

    Eigen-filters with attenuation response adapted to clutter statistics in color flow imaging (CFI) have shown improved flow detection sensitivity in the presence of tissue motion. Nevertheless, its practical adoption in clinical use is not straightforward due to the high computational cost for solving eigendecompositions. Here, we provide a pedagogical description of how a real-time computing framework for eigen-based clutter filtering can be developed through a single-instruction, multiple data (SIMD) computing approach that can be implemented on a graphical processing unit (GPU). Emphasis is placed on the single-ensemble-based eigen-filtering approach (Hankel singular value decomposition), since it is algorithmically compatible with GPU-based SIMD computing. The key algebraic principles and the corresponding SIMD algorithm are explained, and annotations on how such algorithm can be rationally implemented on the GPU are presented. Real-time efficacy of our framework was experimentally investigated on a single GPU device (GTX Titan X), and the computing throughput for varying scan depths and slow-time ensemble lengths was studied. Using our eigen-processing framework, real-time video-range throughput (24 frames/s) can be attained for CFI frames with full view in azimuth direction (128 scanlines), up to a scan depth of 5 cm ( λ pixel axial spacing) for slow-time ensemble length of 16 samples. The corresponding CFI image frames, with respect to the ones derived from non-adaptive polynomial regression clutter filtering, yielded enhanced flow detection sensitivity in vivo, as demonstrated in a carotid imaging case example. These findings indicate that the GPU-enabled eigen-based clutter filtering can improve CFI flow detection performance in real time.

  12. Measurements and Analysis of Reverberation, Target Echo, and Clutter: FY10 Annual Report for ONR

    Science.gov (United States)

    2010-09-30

    NATO Undersea Research Centre ( NURC ). The primary effort is analysis and interpretation of data, together with development and validation of improved...Research Projects (JRPs) between NURC , Canada, and several US research laboratories (ARL in particular). The present JRP “Characterizing and Reducing...Canada/ NURC Joint Research Project “Characterizing and Reducing Clutter in Broadband Active Sonar” which received substantial funding from ONR. A

  13. Quasi-Analytic Model of OTHR Clutter from Equatorial Bubbles in the Ionosphere

    Science.gov (United States)

    2006-02-27

    raytrace code developed to study OTH radar clutter is based on the theory provided by Hazelgrove [1954], Yeh and Liu [1972], Jones and Stephenson [1975... radar (OTHR) sky wave becomes Doppler shifted because the ionosphere through which the radio rays are propagating changes. One source of these changes...trace computations to yield predictions for Doppler shifts in the unstable ionosphere. 15. SUBJECT TERMS Over-the-horizon radar Computer model of the

  14. The Application of JDL to Suppress Sea Clutter for Shipborne HFSWR

    Directory of Open Access Journals (Sweden)

    Zhenyuan Ji

    2015-01-01

    Full Text Available This paper deals with the problem of sea clutter suppression for shipborne high frequency surface wave radar (HFSWR based on the joint domain localized (JDL adaptive processing algorithm. The performance of the novel method is compared with 2D FFT plus digital beamforming (FFT-DBF and orthogonal weight in different azimuths. The results based on simulated and real data show that the novel method provides higher detection performance than others.

  15. The Application of JDL to Suppress Sea Clutter for Shipborne HFSWR

    OpenAIRE

    2015-01-01

    This paper deals with the problem of sea clutter suppression for shipborne high frequency surface wave radar (HFSWR) based on the joint domain localized (JDL) adaptive processing algorithm. The performance of the novel method is compared with 2D FFT plus digital beamforming (FFT-DBF) and orthogonal weight in different azimuths. The results based on simulated and real data show that the novel method provides higher detection performance than others.

  16. Duct heights inferred from radar sea clutter using proper orthogonal bases

    Science.gov (United States)

    Fountoulakis, Vasileios; Earls, Christopher

    2016-10-01

    Maritime electromagnetic (EM)-based communication and detection systems are strongly influenced by meteorological conditions, as they can cause anomalous electromagnetic propagation within the surface layer. To predict the performance of such systems, detailed knowledge of the refractivity profile is required. In recent years, refractivity from clutter (RFC) methods has been developed to estimate this refractivity profile by measuring radar clutter return from the rough ocean surface. The current work proposes an RFC framework that utilizes a novel surrogate model for EM propagation. The surrogate model is based on an offline created library of sparsely sampled field data of clutter returns, compressed into proper orthogonal bases, and indexed on specific surface layer refractive parameters. By exploiting the Riemannian manifold structure of the space that proper orthogonal bases occur in, we are able to interpolate among them. This, then, enables us to use the surrogate model in an inverse problem setting, whose goal is to uncover in situ maritime EM propagation conditions efficiently. We demonstrate the feasibility of our proposed surrogate model-based RFC approach for evaporation duct by testing it with field data obtained from an experimental campaign.

  17. Age differences in search of web pages: the effects of link size, link number, and clutter.

    Science.gov (United States)

    Grahame, Michael; Laberge, Jason; Scialfa, Charles T

    2004-01-01

    Reaction time, eye movements, and errors were measured during visual search of Web pages to determine age-related differences in performance as a function of link size, link number, link location, and clutter. Participants (15 young adults, M = 23 years; 14 older adults, M = 57 years) searched Web pages for target links that varied from trial to trial. During one half of the trials, links were enlarged from 10-point to 12-point font. Target location was distributed among the left, center, and bottom portions of the screen. Clutter was manipulated according to the percentage of used space, including graphics and text, and the number of potentially distracting nontarget links was varied. Increased link size improved performance, whereas increased clutter and links hampered search, especially for older adults. Results also showed that links located in the left region of the page were found most easily. Actual or potential applications of this research include Web site design to increase usability, particularly for older adults.

  18. Improved Shape Parameter Estimation in K Clutter with Neural Networks and Deep Learning

    Directory of Open Access Journals (Sweden)

    José Raúl Fernández Machado

    2016-06-01

    Full Text Available The discrimination of the clutter interfering signal is a current problem in modern radars’ design, especially in coastal or offshore environments where the histogram of the background signal often displays heavy tails. The statistical characterization of this signal is very important for the cancellation of sea clutter, whose behavior obeys a K distribution according to the commonly accepted criterion. By using neural networks, the authors propose a new method for estimating the K shape parameter, demonstrating its superiority over the classic alternative based on the Method of Moments. Whereas both solutions have a similar performance when the entire range of possible values of the shape parameter is evaluated, the neuronal alternative achieves a much more accurate estimation for the lower Fig.s of the parameter. This is exactly the desired behavior because the best estimate occurs for the most aggressive states of sea clutter. The final design, reached by processing three different sets of computer generated K samples, used a total of nine neural networks whose contribution is synthesized in the final estimate, thus the solution can be interpreted as a deep learning approximation. The results are to be applied in the improvement of radar detectors, particularly for maintaining the operational false alarm probability close to the one conceived in the design.

  19. Physicians' Abdominal Auscultation

    DEFF Research Database (Denmark)

    John, Gade; Peter, Kruse; Andersen, Ole Trier

    1998-01-01

    Background: Abdominal auscultation has an important position in the physical examination of the abdomen. Little is known about rater agreement. The aim of this study was to describe rater agreement and thus, indirectly, the value of the examination. Methods: In a semi-virtual setup 12 recordings...... of the intestinal sounds from 8 patients with acute abdominal pain and 4 healthy volunteers were presented to 100 physicians. The physicians were asked to characterize the intestinal sounds as normal or pathologic. Fisher's exact test was used for comparison between groups of physicians. Results: Overall, 72......% of the answers with regard to healthy volunteers concluded that the sounds were normal (equalling agreement), whereas 64% of answers with regard to intestinal obstruction concluded that the sounds were pathologic (but agreement was higher due to agreement on wrong diagnosis in one case). Bowel sounds from...

  20. Endometrioma de parede abdominal

    Directory of Open Access Journals (Sweden)

    Italo Accetta

    Full Text Available OBJETIVO: Relatar a experiência dos autores com as manifestações clínicas e o tratamento cirúrgico em pacientes com endometrioma de parede abdominal. MÉTODOS: Análise retrospectiva das pacientes operadas por endometrioma de parede abdominal, dando ênfase aos dados relativos à idade, sintomas, cesariana prévia, relação dos sintomas com o ciclo menstrual, exames físicos e complementares, tratamento cirúrgico, evolução pós-operatória e resultado histopatológico dos espécimes. RESULTADOS: Foram operadas 14 pacientes no período estudado, com idade entre 28 e 40 anos. A presença de massa e dor local que piorava durante a menstruação foram as queixas principais. Ultrassonografia e tomografia computadorizada foram exames importantes em localizar precisamente a doença. O tratamento cirúrgico foi exérese ampla da tumoração e dos tecidos comprometidos. As pacientes evoluíram satisfatoriamente e o histopatológico confirmou a suspeita de endometrioma de parede abdominal em todos os casos. CONCLUSÃO: Foi nítida a relação entre cesariana prévia e endometrioma de parede abdominal e estudos ultrassonográficos e tomográficos auxiliaram a planejar a abordagem cirúrgica permitindo a exérese da tumoração e de todos os tecidos adjacentes comprometidos.

  1. Ruptured abdominal aortic aneurysm.

    Science.gov (United States)

    Sachs, T; Schermerhorn, M

    2010-06-01

    Ruptured abdominal aortic aneurysm (AAA) continues to be one of the most lethal vascular pathologies we encounter. Its management demands prompt and efficient evaluation and repair. Open repair has traditionally been the mainstay of treatment. However, the introduction of endovascular techniques has altered the treatment algorithm for ruptured AAA in most major medical centers. We present recent literature and techniques for ruptured AAA and its surgical management.

  2. Abdominal aspergillosis: CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Yeom, Suk Keu, E-mail: pagoda20@hanmail.net [Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Poongnap2-dong, Songpa-gu, Seoul, 138-736 (Korea, Republic of); Kim, Hye Jin, E-mail: kimhyejin@amc.seoul.kr [Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Poongnap2-dong, Songpa-gu, Seoul, 138-736 (Korea, Republic of); Byun, Jae Ho, E-mail: jhbyun@amc.seoul.kr [Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Poongnap2-dong, Songpa-gu, Seoul, 138-736 (Korea, Republic of); Kim, Ah Young, E-mail: aykim@amc.seoul.kr [Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Poongnap2-dong, Songpa-gu, Seoul, 138-736 (Korea, Republic of); Lee, Moon-Gyu, E-mail: mglee@amc.seoul.kr [Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Poongnap2-dong, Songpa-gu, Seoul, 138-736 (Korea, Republic of); Ha, Hyun Kwon, E-mail: hkha@amc.seoul.kr [Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Poongnap2-dong, Songpa-gu, Seoul, 138-736 (Korea, Republic of)

    2011-03-15

    Objective: In order to retrospectively evaluate the CT findings of abdominal aspergillosis in immunocompromised patients. Materials and methods: CT scans were reviewed with regard to the sites, number, morphologic appearance, attenuation, and the contrast enhancement patterns of the lesions in six patients (5 women, 1 man; mean age, 43.4 years; range, 23-59 years) with pathologically proved abdominal aspergillosis by two gastrointestinal radiologists in consensus. Medical records were also reviewed to determine each patient's clinical status and outcome. Results: All patients were immunocompromised state: 4 patients received immunosuppressive therapy for solid organ transplantation and 2 patients received chemotherapy for acute myeloid leukemia. Aspergillosis involved blood vessels (n = 3), liver (n = 2), spleen (n = 2), gastrointestinal tract (n = 2), native kidney (n = 1), transplanted kidney (n = 1), peritoneum (n = 1), and retroperitoneum (n = 1). CT demonstrated solid organ or bowel infarction or perforation secondary to vascular thrombosis or pseudoaneurysm, multiple low-attenuating lesions of solid organs presenting as abscesses, concentric bowel wall thickening mimicking typhlitis, or diffuse or nodular infiltration of the peritoneum and retroperitoneum. Conclusion: Familiarity with findings commonly presenting as angioinvasive features or abscesses on CT, may facilitate the diagnosis of rare and fatal abdominal aspergillosis.

  3. Logarithmic r-θ mapping for hybrid optical neural network filter for multiple objects recognition within cluttered scenes

    Science.gov (United States)

    Kypraios, Ioannis; Young, Rupert C. D.; Chatwin, Chris R.; Birch, Phil M.

    2009-04-01

    θThe window unit in the design of the complex logarithmic r-θ mapping for hybrid optical neural network filter can allow multiple objects of the same class to be detected within the input image. Additionally, the architecture of the neural network unit of the complex logarithmic r-θ mapping for hybrid optical neural network filter becomes attractive for accommodating the recognition of multiple objects of different classes within the input image by modifying the output layer of the unit. We test the overall filter for multiple objects of the same and of different classes' recognition within cluttered input images and video sequences of cluttered scenes. Logarithmic r-θ mapping for hybrid optical neural network filter is shown to exhibit with a single pass over the input data simultaneously in-plane rotation, out-of-plane rotation, scale, log r-θ map translation and shift invariance, and good clutter tolerance by recognizing correctly the different objects within the cluttered scenes. We record in our results additional extracted information from the cluttered scenes about the objects' relative position, scale and in-plane rotation.

  4. Abdominal aortic aneurysm surgery

    DEFF Research Database (Denmark)

    Gefke, K; Schroeder, T V; Thisted, B

    1994-01-01

    The goal of this study was to identify patients who need longer care in the ICU (more than 48 hours) following abdominal aortic aneurysm (AAA) surgery and to evaluate the influence of perioperative complications on short- and long-term survival and quality of life. AAA surgery was performed in 553......, 78% stated that their quality of life had improved or was unchanged after surgery and had resumed working. These data justify a therapeutically aggressive approach, including ICU therapy following AAA surgery, despite failure of one or more organ systems....

  5. Abdominal perfusion computed tomography.

    Science.gov (United States)

    Ogul, Hayri; Bayraktutan, Ummugulsum; Kizrak, Yesim; Pirimoglu, Berhan; Yuceler, Zeynep; Sagsoz, M Erdem; Yilmaz, Omer; Aydinli, Bulent; Ozturk, Gurkan; Kantarci, Mecit

    2013-02-01

    The purpose of this article is to provide an up to date review on the spectrum of applications of perfusion computed tomography (CT) in the abdomen. New imaging techniques have been developed with the objective of obtaining a structural and functional analysis of different organs. Recently, perfusion CT has aroused the interest of many researchers who are studying the applicability of imaging modalities in the evaluation of abdominal organs and diseases. Per-fusion CT enables fast, non-invasive imaging of the tumor vascular physiology. Moreover, it can act as an in vivo biomarker of tumor-related angiogenesis.

  6. Lower Abdominal Pain.

    Science.gov (United States)

    Carlberg, David J; Lee, Stephen D; Dubin, Jeffrey S

    2016-05-01

    Although most frequently presenting with lower abdominal pain, appendicitis, colitis, and diverticulitis can cause pain throughout the abdomen and can cause peritoneal and retroperitoneal symptoms. Evaluation and management of lower intestinal disease requires a nuanced approach by the emergency physician, sometimes requiring computed tomography, ultrasonography, MRI, layered imaging, shared decision making, serial examination, and/or close follow-up. Once a presumed or confirmed diagnosis is made, appropriate treatment is initiated, and may include surgery, antibiotics, and/or steroids. Appendicitis patients should be admitted. Diverticulitis and inflammatory bowel disease can frequently be managed on an outpatient basis, but may require admission and surgical consultation.

  7. Dolor abdominal recurrente .

    Directory of Open Access Journals (Sweden)

    Rodrigo De Vivero

    2009-11-01

    Full Text Available El dolor abdominal recurrente (DAR es un problema frecuente en la consulta médica y en la subespecialidad médica y quirúrgica. El DAR es frecuentemente funcional, es decir, sin una causa orgánica aparente. El diagnóstico diferencial debe incluir pérdida de peso, sangrado gastrointestinal, fiebre persistente, diarrea crónica y vómito importante. En este artículo se revisa el diagnóstico y tratamiento, pruebas diagnósticas y manejo farmacológico y ambiental.

  8. [Differential diagnosis of abdominal pain].

    Science.gov (United States)

    Frei, Pascal

    2015-09-02

    Despite the frequency of functional abdominal pain, potentially dangerous causes of abdominal pain need to be excluded. Medical history and clinical examination must focus on red flags and signs for imflammatory or malignant diseases. See the patient twice in the case of severe and acute abdominal pain if lab parameters or radiological examinations are normal. Avoid repeated and useless X-ray exposure whenever possible. In the case of subacute or chronic abdominal pain, lab tests such as fecal calprotectin, helicobacter stool antigen and serological tests for celiac disease are very useful. Elderly patients may show atypical or missing clinical signs. Take care of red herrings and be skeptical whether your initial diagnosis is really correct. Abdominal pain can frequently be an abdominal wall pain.

  9. Abdominal wall blocks in adults

    DEFF Research Database (Denmark)

    Børglum, Jens; Gögenür, Ismail; Bendtsen, Thomas F

    2016-01-01

    Purpose of review Abdominal wall blocks in adults have evolved much during the last decade; that is, particularly with the introduction of ultrasound-guided (USG) blocks. This review highlights recent advances of block techniques within this field and proposes directions for future research.......  Recent findings Ultrasound guidance is now considered the golden standard for abdominal wall blocks in adults, even though some landmark-based blocks are still being investigated. The efficiency of USG transversus abdominis plane blocks in relation to many surgical procedures involving the abdominal wall...... been introduced with success. Future research should also investigate the effect of specific abdominal wall blocks on neuroendocrine and inflammatory stress response after surgery.  Summary USG abdominal wall blocks in adults are commonplace techniques today. Most abdominal wall blocks are assigned...

  10. Joint statistical correction of clutters, spokes and beam height for a radar climatology in Southern Germany

    Directory of Open Access Journals (Sweden)

    A. Wagner

    2012-04-01

    Full Text Available Extensive corrections of radar data are a crucial prerequisite for radar derived climatology. This kind of climatology demands a high level of data quality. Little deviations or minor systematic underestimations or overestimations in single radar images become a major cause of error in statistical analysis. First results of radar derived climatology have emerged over the last years, as data sets of appropriate extent are becoming available. Usually, these statistics are based on time series lasting up to ten years as storage of radar data was not achieved before.

    We present a new statistical post-correction scheme, which is based on seven years of radar data of the Munich weather radar (2000–2006 that is operated by DWD (German Weather Service. The typical correction algorithms for single radar images, such as clutter corrections, are used. Then an additional statistical post-correction based on the results of a climatological analysis from radar images follows. The aim of this statistical correction is to correct systematic errors caused by clutter effects or measuring effects but to conserve small-scale natural variations in space.

    The statistical correction is based on a thorough analysis of the different causes of possible errors for the Munich weather radar. This robust analysis revealed the following basic effects: the decrease of rain rate in relation to height and distance from the radar, clutter effects such as remaining clutter, eliminated clutter or shading effects from obstacles near the radar, visible as spokes, as well as the influence of the Bright Band. The correction algorithm is correspondingly based on these results. It consists of three modules. The first one is an altitude correction, which minimizes measuring effects. The second module corrects clutter effects and the third one realizes a mean adjustment to selected rain gauges. Two different radar products are used. The statistical analysis as well as

  11. Abdominal cystic lymphangioma mimicking appendicitis.

    Science.gov (United States)

    Wake, Sarah; Abhyankar, Aruna; Hutton, Kim

    2013-06-01

    A cystic lymphangioma arising within the abdomen is a rare entity in children. It may present with an abdominal mass and symptoms of abdominal pain, vomiting, and anorexia. These nonspecific clinical symptoms are often attributed to more common acute pediatric conditions. In this report, we describe two pediatric cases of intra-abdominal cystic lymphangioma that were initially diagnosed and treated as appendicitis. True diagnosis was only achieved on surgical excision and pathological investigation of cystic material.

  12. Abdominal Cystic Lymphangioma Mimicking Appendicitis

    OpenAIRE

    Wake, Sarah; Abhyankar, Aruna; Hutton, Kim

    2013-01-01

    A cystic lymphangioma arising within the abdomen is a rare entity in children. It may present with an abdominal mass and symptoms of abdominal pain, vomiting, and anorexia. These nonspecific clinical symptoms are often attributed to more common acute pediatric conditions. In this report, we describe two pediatric cases of intra-abdominal cystic lymphangioma that were initially diagnosed and treated as appendicitis. True diagnosis was only achieved on surgical excision and pathological investi...

  13. Abdominal pregnancy- a case report.

    Science.gov (United States)

    Okafor, Ii; Ude, Ac; Aderibigbe, Aso; Amu, Oc; Udeh, Pe; Obianyo, Nen; Ani, Coc

    2011-01-01

    A case of abdominal pregnancy in a 39 year old female gravida 4, para 0(+3) is presented. Ultrasonography revealed a viable abdominal pregnancy at 15 weeks gestational age. She was initially managed conservatively. Surgical intervention became necessary at 20 weeks gestational age following Ultrasound detection of foetal demise. The maternal outcome was favourable. This case is presented to highlight the dilemma associated with diagnosis and management of abdominal pregnancy with a review of literature.

  14. Children's (Pediatric) Abdominal Ultrasound Imaging

    Medline Plus

    Full Text Available ... through blood vessels. Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions. Children's (pediatric) abdominal ultrasound imaging produces pictures ...

  15. Abdominal parametric perfusion imaging with respiratory motion-compensation based on contrast-enhanced ultrasound: In-vivo validation.

    Science.gov (United States)

    Wang, Diya; Xiao, Mengnan; Zhang, Yu; Wan, Mingxi

    2017-06-22

    Parametric perfusion imaging (PPI) based on dynamic contrast-enhanced ultrasound (DCEUS) is a multi-parametric functional method that is increasingly used to characterize the hemodynamic features of abdominal tumors. Periodic respiratory kinetics adversely affects the signal-to-clutter ratio (SCR) and accuracy of abdominal PPI. This study proposed respiratory motion-compensation (rMoCo) employing non-negative matrix factorization combined with fast block matching algorithm to effectively remove these disturbances on abdominal PPI, which was validated through in-vivo perfusion experiments. The mean calculation efficiency of rMoCo was improved by 83.6% when the algorithm was accelerated in a unique matching sequence, which was formed from dozens of DCEUS subsequences at the same respiratory phase. The horizontal and vertical displacements induced by respiratory kinetics were estimated to correct the extraction of time-intensity curves and the peak SNR remained at 22.58±2.90dB. Finally, the abdominal PPIs of four perfusion parameters were formed with non-negative rMoCo, and their SCR was improved by 3.99±0.49dB (pbenefits clinicians in providing accurate diagnoses and in developing appropriate therapeutic strategies for abdominal diseases. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Simplified formulae for the estimation of offshore wind turbines clutter on marine radars.

    Science.gov (United States)

    Grande, Olatz; Cañizo, Josune; Angulo, Itziar; Jenn, David; Danoon, Laith R; Guerra, David; de la Vega, David

    2014-01-01

    The potential impact that offshore wind farms may cause on nearby marine radars should be considered before the wind farm is installed. Strong radar echoes from the turbines may degrade radars' detection capability in the area around the wind farm. Although conventional computational methods provide accurate results of scattering by wind turbines, they are not directly implementable in software tools that can be used to conduct the impact studies. This paper proposes a simple model to assess the clutter that wind turbines may generate on marine radars. This method can be easily implemented in the system modeling software tools for the impact analysis of a wind farm in a real scenario.

  17. Detecting Weather Radar Clutter by Information Fusion With Satellite Images and Numerical Weather Prediction Model Output

    DEFF Research Database (Denmark)

    Bøvith, Thomas; Nielsen, Allan Aasbjerg; Hansen, Lars Kai

    2006-01-01

    A method for detecting clutter in weather radar images by information fusion is presented. Radar data, satellite images, and output from a numerical weather prediction model are combined and the radar echoes are classified using supervised classification. The presented method uses indirect...... information on precipitation in the atmosphere from Meteosat-8 multispectral images and near-surface temperature estimates from the DMI-HIRLAM-S05 numerical weather prediction model. Alternatively, an operational nowcasting product called 'Precipitating Clouds' based on Meteosat-8 input is used. A scale...

  18. Measurements and Analysis of Reverberation, Target Echo, and Clutter: FY11 Annual Report for ONR

    Science.gov (United States)

    2011-09-01

    and sonar workshop problems using an adiabatic normal mode model. In Papadakis and Bjørnø [PB11], pages 485–490. Contributed paper in Structured...and clutter data from the Malta Plateau. In Papadakis and Bjørnø [PB11], pages 657–664. Invited paper in Structured Session “Temporal and Spatial...Marigola, Lerici, Italy, 9–12 September 2008. [PB11] John S. Papadakis and Leif Bjørnø, editors. 4th International Conference on Underwater

  19. Nontraumatic abdominal emergencies: acute abdominal pain: diagnostic strategies

    Energy Technology Data Exchange (ETDEWEB)

    Marincek, B. [Institute of Diagnostic Radiology, University Hospital Zurich, Raemistrasse 100, 8091 Zurich (Switzerland)

    2002-09-01

    Common causes of acute abdominal pain include appendicitis, cholecystitis, bowel obstruction, urinary colic, perforated peptic ulcer, pancreatitis, diverticulitis, and nonspecific, nonsurgical abdominal pain. The topographic classification of acute abdominal pain (pain in one of the four abdominal quadrants, diffuse abdominal pain, flank or epigastric pain) facilitates the choice of the imaging technique. The initial radiological evaluation often consists of plain abdominal radiography, despite significant diagnostic limitations. The traditional indications for plain films - bowel obstruction, pneumoperitoneum, and the search of ureteral calculi - are questioned by helical computed tomography (CT). Although ultrasonography (US) is in many centers the modality of choice for imaging the gallbladder and the pelvis in children and women of reproductive age, CT is considered to be one of the most valued tools for triaging patients with acute abdominal pain. CT is particularly beneficial in patients with marked obesity, unclear US findings, bowel obstruction, and multiple lesions. The introduction of multidetector row CT (MDCT) has further enhanced the utility of CT in imaging patients with acute abdominal pain. (orig.)

  20. Measurement of nadir and near-nadir 94-GHz brightness temperatures of several tactical-scene clutter types

    Science.gov (United States)

    Wikner, David A.; Pizzillo, Thomas J.

    1999-07-01

    The authors present 94-GHz radiometric brightness temperatures of various clutter materials at nadir. The clutter materials measured include field vegetation, asphalt pavement, and an asphalt shingle roof and data is presented for each clutter type. We also report measurements that quantify the effect of water on the brightness temperature of metal. These measurements were made by adding calibrated quantities of water to a metal plate while recording the plate's millimeter-wave brightness temperature. Off-nadir data out to 45 deg is also presented for the field vegetation and asphalt pavement. Using a simple rough scattering model for the materials, we made estimates of the emissivity of the field vegetation and asphalt. The emissivity of the roof was determined by measuring its brightness temperature as it was heated.

  1. Modeling and Analysis of Target Echo and Clutter in Range-Dependent Bistatic Environments: FY12 Annual Report for ONR

    Science.gov (United States)

    2012-09-30

    and sonar workshop problems using an adiabatic normal mode model. In Papadakis and Bjørnø [PB11], pages 485–490. Contributed paper in Structured...Clutter Model: Range-dependent predictions compared with towed array reverberation and clutter data from the Malta Plateau. In Papadakis and Bjørnø...35(3):502–515, 2010. 10 [PB11] John S. Papadakis and Leif Bjørnø, editors. 4th International Conference on Underwater Acoustic Measurements

  2. Abdominal Complications after Severe Burns

    Science.gov (United States)

    2009-05-01

    abdominal compartment syndrome, schemic bowel, biliary disease , peptic ulcer disease and astritis requiring laparotomy, small bowel obstruction, rimary fungal...complications in- luded trauma exploratory laparotomy, abdominal com- artment syndrome, ischemic bowel, biliary disease , peptic lcer disease and gastritis, large...because it was almost uniformly ssociated with serious lethal burns. This was in the period efore effective gastric acid control, explaining the high

  3. Videolaparoscopia no trauma abdominal

    Directory of Open Access Journals (Sweden)

    Átila Varela Velho

    Full Text Available A videolaparoscopia (VL vem contribuindo de forma crescente, para diagnóstico e terapêutica de várias afecções cirúrgicas abdominais, introduzindo profundas mudanças na cirurgia contemporânea. Esse avanço incorporou-se também às urgências traumáticas, fazendo parte da avaliação diagnóstica e, às vezes, da terapêutica do trauma abdominal. Os autores apresentam uma revisão concisa da literatura sobre a VL no trauma, atualizando o tema e discutindo os aspectos mais relevantes das indicações, limitações e complicações do método.

  4. Abdominal aortic aneurysms

    DEFF Research Database (Denmark)

    Lindholt, Jes Sanddal

    2010-01-01

    Although the number of elective operations for abdominal aortic aneurysms (AAA) is increasing, the sex- and age-standardised mortality rate of AAAs continues to rise, especially among men aged 65 years or more. The lethality of ruptured AAA continues to be 80-95%, compared with 5-7% by elective...... inhibit further AAA progression. All 4 existing RCTs point in the same direction, viz. in favour of screening of men aged 65 and above. We found that screening significantly reduced AAA-related mortality by 67% within the first five years (NNT = 352). Restriction of screening to men with previous...... year gained was 157 euro [1,170 DKK] and the cost per QALY at 178 euro [1,326 DKK]. In all, the ethical dilemma of the prophylactic operation, and the limited psychological side effects seem not to outweigh the benefits of screening. Conclusively, we found that offering men aged 65-73 years screening...

  5. Big brown bats (Eptesicus fuscus) reveal diverse strategies for sonar target tracking in clutter.

    Science.gov (United States)

    Mao, Beatrice; Aytekin, Murat; Wilkinson, Gerald S; Moss, Cynthia F

    2016-09-01

    Bats actively adjust the acoustic features of their sonar calls to control echo information specific to a given task and environment. A previous study investigated how bats adapted their echolocation behavior when tracking a moving target in the presence of a stationary distracter at different distances and angular offsets. The use of only one distracter, however, left open the possibility that a bat could reduce the interference of the distracter by turning its head. Here, bats tracked a moving target in the presence of one or two symmetrically placed distracters to investigate adaptive echolocation behavior in a situation where vocalizing off-axis would result in increased interference from distracter echoes. Both bats reduced bandwidth and duration but increased sweep rate in more challenging distracter conditions, and surprisingly, made more head turns in the two-distracter condition compared to one, but only when distracters were placed at large angular offsets. However, for most variables examined, subjects showed distinct strategies to reduce clutter interference, either by (1) changing spectral or temporal features of their calls, or (2) producing large numbers of sonar sound groups and consistent head-turning behavior. The results suggest that individual bats can use different strategies for target tracking in cluttered environments.

  6. Radar signatures of indoor clutter for through-the-wall radar applications

    Science.gov (United States)

    Bufler, Travis D.; Narayanan, Ram M.; Dogaru, Traian

    2014-05-01

    In through-the-wall radar (TTWR) applications, scattering by indoor clutter elements can greatly confound the detection of humans. This paper analyzes the spectral and azimuthal scattering characteristics of various types of individual furniture targets and compares these to humans. Radar cross section (RCS) values of furniture and humans are obtained using the finite difference time domain (FDTD) technique over the 1-5 GHz frequency range and the 0-360 azimuth angle range for both co- and cross-polarized scattering. In the case of furniture, RCS responses show to the highest returns when viewing the planar surfaces of the clutter objects. Objects consisting primarily of smaller planar surfaces with more complex geometrical features showed a more uniform response with no preferred orientation showing a larger response. Human RCS produced from the biological models showed a more constant RCS when viewing the co-polarized response, where the back produced the highest response due to the more planar surface. The cross-polarized response was more varied providing for a wider range of RCS values.

  7. The estimation of lower refractivity uncertainty from radar sea clutter using the Bayesian-MCMC method

    Institute of Scientific and Technical Information of China (English)

    Sheng Zheng

    2013-01-01

    The estimation of lower atmospheric refractivity from radar sea clutter (RFC) is a complicated nonlinear optimization problem.This paper deals with the RFC problem in a Bayesian framework.It uses the unbiased Markov Chain Monte Carlo (MCMC) sampling technique,which can provide accurate posterior probability distributions of the estimated refractivity parameters by using an electromagnetic split-step fast Fourier transform terrain parabolic equation propagation model within a Bayesian inversion framework.In contrast to the global optimization algorithm,the Bayesian-MCMC can obtain not only the approximate solutions,but also the probability distributions of the solutions,that is,uncertainty analyses of solutions.The Bayesian-MCMC algorithm is implemented on the simulation radar sea-clutter data and the real radar seaclutter data.Reference data are assumed to be simulation data and refractivity profiles are obtained using a helicopter.The inversion algorithm is assessed (i) by comparing the estimated refractivity profiles from the assumed simulation and the helicopter sounding data; (ii) the one-dimensional (1D) and two-dimensional (2D) posterior probability distribution of solutions.

  8. Spatial memory and stereotypy of flight paths by big brown bats in cluttered surroundings.

    Science.gov (United States)

    Barchi, Jonathan R; Knowles, Jeffrey M; Simmons, James A

    2013-03-15

    The big brown bat, Eptesicus fuscus, uses echolocation for foraging and orientation. The limited operating range of biosonar implies that bats must rely upon spatial memory in familiar spaces with dimensions larger than a few meters. Prior experiments with bats flying in obstacle arrays have revealed differences in flight and acoustic emission patterns depending on the density and spatial extent of the obstacles. Using the same method, combined with acoustic microphone array tracking, we flew big brown bats in an obstacle array that varied in density and distribution in different locations in the flight room. In the initial experiment, six bats learned individually stereotyped flight patterns as they became familiar with the space. After the first day, the repetition rate of sonar broadcasts dropped to a stable level, consistent with low-density clutter. In a second experiment, after acquiring their stable paths, each bat was released from each of two unfamiliar locations in the room. Each bat still followed the same flight path it learned originally. In a third experiment, performed 1 month after the first two experiments, three of the bats were re-flown in the same configuration of obstacles; these three resumed flying in their accustomed path. The other three bats were flown in a mirror-image reconfiguration of the obstacles; these bats quickly found stable flight paths that differed from their originally learned paths. Overall, the flight patterns indicate that the bats perceive the cluttered space as a single scene through which they develop globally organized flight paths.

  9. Coordinate-Based Clustering Method for Indoor Fingerprinting Localization in Dense Cluttered Environments

    Directory of Open Access Journals (Sweden)

    Wen Liu

    2016-12-01

    Full Text Available Indoor positioning technologies has boomed recently because of the growing commercial interest in indoor location-based service (ILBS. Due to the absence of satellite signal in Global Navigation Satellite System (GNSS, various technologies have been proposed for indoor applications. Among them, Wi-Fi fingerprinting has been attracting much interest from researchers because of its pervasive deployment, flexibility and robustness to dense cluttered indoor environments. One challenge, however, is the deployment of Access Points (AP, which would bring a significant influence on the system positioning accuracy. This paper concentrates on WLAN based fingerprinting indoor location by analyzing the AP deployment influence, and studying the advantages of coordinate-based clustering compared to traditional RSS-based clustering. A coordinate-based clustering method for indoor fingerprinting location, named Smallest-Enclosing-Circle-based (SEC, is then proposed aiming at reducing the positioning error lying in the AP deployment and improving robustness to dense cluttered environments. All measurements are conducted in indoor public areas, such as the National Center For the Performing Arts (as Test-bed 1 and the XiDan Joy City (Floors 1 and 2, as Test-bed 2, and results show that SEC clustering algorithm can improve system positioning accuracy by about 32.7% for Test-bed 1, 71.7% for Test-bed 2 Floor 1 and 73.7% for Test-bed 2 Floor 2 compared with traditional RSS-based clustering algorithms such as K-means.

  10. Tracking a maneuvering target in clutter with out-of-sequence measurements for airborne radar

    Institute of Scientific and Technical Information of China (English)

    Weihua Wu; Jing Jiang; Yang Wan

    2015-01-01

    There are many proposed optimal or suboptimal al-gorithms to update out-of-sequence measurement(s) (OoSM(s)) for linear-Gaussian systems, but few algorithms are dedicated to track a maneuvering target in clutter by using OoSMs. In order to address the nonlinear OoSMs obtained by the airborne radar located on a moving platform from a maneuvering target in clut-ter, an interacting multiple model probabilistic data association (IMMPDA) algorithm with the OoSM is developed. To be practical, the algorithm is based on the Earth-centered Earth-fixed (ECEF) coordinate system where it considers the effect of the platform’s attitude and the curvature of the Earth. The proposed method is validated through the Monte Carlo test compared with the perfor-mance of the standard IMMPDA algorithm ignoring the OoSM, and the conclusions show that using the OoSM can improve the track-ing performance, and the shorter the lag step is, the greater degree the performance is improved, but when the lag step is large, the performance is not improved any more by using the OoSM, which can provide some references for engineering application.

  11. Robot navigation in cluttered 3-D environments using preference-based fuzzy behaviors.

    Science.gov (United States)

    Shi, Dongqing; Collins, Emmanuel G; Dunlap, Damion

    2007-12-01

    Autonomous navigation systems for mobile robots have been successfully deployed for a wide range of planar ground-based tasks. However, very few counterparts of previous planar navigation systems were developed for 3-D motion, which is needed for both unmanned aerial and underwater vehicles. A novel fuzzy behavioral scheme for navigating an unmanned helicopter in cluttered 3-D spaces is developed. The 3-D navigation problem is decomposed into several identical 2-D navigation subproblems, each of which is solved by using preference-based fuzzy behaviors. Due to the shortcomings of vector summation during the fusion of the 2-D subproblems, instead of directly outputting steering subdirections by their own defuzzification processes, the intermediate preferences of the subproblems are fused to create a 3-D solution region, representing degrees of preference for the robot movement. A new defuzzification algorithm that steers the robot by finding the centroid of a 3-D convex region of maximum volume in the 3-D solution region is developed. A fuzzy speed-control system is also developed to ensure efficient and safe navigation. Substantial simulations have been carried out to demonstrate that the proposed algorithm can smoothly and effectively guide an unmanned helicopter through unknown and cluttered urban and forest environments.

  12. 3-D Laser-Based Multiclass and Multiview Object Detection in Cluttered Indoor Scenes.

    Science.gov (United States)

    Zhang, Xuesong; Zhuang, Yan; Hu, Huosheng; Wang, Wei

    2017-01-01

    This paper investigates the problem of multiclass and multiview 3-D object detection for service robots operating in a cluttered indoor environment. A novel 3-D object detection system using laser point clouds is proposed to deal with cluttered indoor scenes with a fewer and imbalanced training data. Raw 3-D point clouds are first transformed to 2-D bearing angle images to reduce the computational cost, and then jointly trained multiple object detectors are deployed to perform the multiclass and multiview 3-D object detection. The reclassification technique is utilized on each detected low confidence bounding box in the system to reduce false alarms in the detection. The RUS-SMOTEboost algorithm is used to train a group of independent binary classifiers with imbalanced training data. Dense histograms of oriented gradients and local binary pattern features are combined as a feature set for the reclassification task. Based on the dalian university of technology (DUT)-3-D data set taken from various office and household environments, experimental results show the validity and good performance of the proposed method.

  13. Phase-modulated waveform design for extended target detection in the presence of clutter.

    Science.gov (United States)

    Gong, Xuhua; Meng, Huadong; Wei, Yimin; Wang, Xiqin

    2011-01-01

    The problem to be addressed in this paper is a phase-modulated waveform design for the detection of extended targets contaminated by signal-dependent noise (clutter) and additive noise in practical radar systems. An optimal waveform design method that leads to the energy spectral density (ESD) of signal under the maximum signal-to-clutter-and-noise ratio (SCNR) criterion is introduced first. In order to make full use of the transmission power, a novel phase-iterative algorithm is then proposed for designing the phase-modulated waveform with a constant envelope, whose ESD matches the optimal one. This method is proven to be able to achieve a small SCNR loss by minimizing the mean-square spectral distance between the optimal waveform and the designed waveform. The results of extensive simulations demonstrate that our approach provides less than 1 dB SCNR loss when the signal duration is greater than 1 μs, and outperforms the stationary phase method and other phase-modulated waveform design methods.

  14. Coordinate-Based Clustering Method for Indoor Fingerprinting Localization in Dense Cluttered Environments.

    Science.gov (United States)

    Liu, Wen; Fu, Xiao; Deng, Zhongliang

    2016-12-02

    Indoor positioning technologies has boomed recently because of the growing commercial interest in indoor location-based service (ILBS). Due to the absence of satellite signal in Global Navigation Satellite System (GNSS), various technologies have been proposed for indoor applications. Among them, Wi-Fi fingerprinting has been attracting much interest from researchers because of its pervasive deployment, flexibility and robustness to dense cluttered indoor environments. One challenge, however, is the deployment of Access Points (AP), which would bring a significant influence on the system positioning accuracy. This paper concentrates on WLAN based fingerprinting indoor location by analyzing the AP deployment influence, and studying the advantages of coordinate-based clustering compared to traditional RSS-based clustering. A coordinate-based clustering method for indoor fingerprinting location, named Smallest-Enclosing-Circle-based (SEC), is then proposed aiming at reducing the positioning error lying in the AP deployment and improving robustness to dense cluttered environments. All measurements are conducted in indoor public areas, such as the National Center For the Performing Arts (as Test-bed 1) and the XiDan Joy City (Floors 1 and 2, as Test-bed 2), and results show that SEC clustering algorithm can improve system positioning accuracy by about 32.7% for Test-bed 1, 71.7% for Test-bed 2 Floor 1 and 73.7% for Test-bed 2 Floor 2 compared with traditional RSS-based clustering algorithms such as K-means.

  15. Phase-Modulated Waveform Design for Extended Target Detection in the Presence of Clutter

    Directory of Open Access Journals (Sweden)

    Xiqin Wang

    2011-07-01

    Full Text Available The problem to be addressed in this paper is a phase-modulated waveform design for the detection of extended targets contaminated by signal-dependent noise (clutter and additive noise in practical radar systems. An optimal waveform design method that leads to the energy spectral density (ESD of signal under the maximum signal-to-clutter-and-noise ratio (SCNR criterion is introduced first. In order to make full use of the transmission power, a novel phase-iterative algorithm is then proposed for designing the phase-modulated waveform with a constant envelope, whose ESD matches the optimal one. This method is proven to be able to achieve a small SCNR loss by minimizing the mean-square spectral distance between the optimal waveform and the designed waveform. The results of extensive simulations demonstrate that our approach provides less than 1 dB SCNR loss when the signal duration is greater than 1 μs, and outperforms the stationary phase method and other phase-modulated waveform design methods.

  16. Haemodynamic and respiratory effects of an abdominal compression binder

    DEFF Research Database (Denmark)

    Toft, M.H.; Bulow, J.; Simonsen, L.

    2008-01-01

    In order to elucidate the circulatory and respiratory effects of a newly developed abdominal compression binder 25 healthy, normal weight subjects were studied. In supine position the central haemodynamics were measured and estimated with a Finapress device. Lower extremity venous haemodynamics...... with or without the abdominal compression binder. The results show that the compression binder significantly increases the venous volume in the lower extremities as showed by a reduction in the venous capacitance in the lower extremities and a reduction in the stroke volume and cardiac output, while it does...... not influence the pulmonary volumes. It is concluded that the applied abdominal binder significantly affects peripheral and central haemodynamics. It should therefore be used with caution when in the supine position for longer periods, as the pooling of blood it induces in the lower extremities may have...

  17. Abdominal migraine in the differential diagnosis of acute abdominal pain.

    Science.gov (United States)

    Cervellin, Gianfranco; Lippi, Giuseppe

    2015-06-01

    Although traditionally regarded as a specific pediatric disease, abdominal migraine may also be observed in adults. Unfortunately, however, this condition is frequently overlooked in the differential diagnosis of abdominal pain in the emergency department (ED). A 30-year-old woman presented to our ED complaining of abdominal pain and vomiting, lasting for 12 hours. The pain was periumbilical, continuous, and not associated with fever or diarrhea. The physical examination and the results of conventional blood tests were normal. The patient was treated with intravenous ketoprofen, metoclopramide, and ranitidine, obtaining a prompt relief of symptoms. She had a history of similar episodes in the last 15 years, with several ED visits, blood test examinations, ultrasonography of the abdomen, and upper gastrointestinal endoscopies. Celiac disease, porphyry, sickle cell disease, and inflammatory bowel disease were all excluded. In July 2012, she became pregnant, and she delivered a healthy baby on April 2013. Until November 2014, she has remained asymptomatic. Based on the clinical characteristics of the abdominal pain episodes, the exclusion of any alternative diagnosis, and the relief of symptoms during and after pregnancy, a final diagnosis of abdominal migraine could be established. A skilled emergency physician should always consider abdominal migraine in the differential diagnosis of patients admitted to the ED with abdominal pain, especially when the attacks are recurrent and no alternative diagnosis can be clearly established.

  18. VACUUM THERAPY VERSUS ABDOMINAL EXERCISES ON ABDOMINAL OBESITY

    Directory of Open Access Journals (Sweden)

    Nevein Mohammed Mohammed Gharib

    2016-06-01

    Full Text Available Background: Obesity is a medical condition that may adversely affect wellbeing and leading to increased incidence of many health problems. Abdominal obesity tends to be associated with weight gain and obesity and it is significantly connected with different disorders like coronary heart disease and type II diabetes mellitus.This study was conducted to investigate the efficacy of vacuum therapy as compared to abdominal exercises on abdominal obesity in overweight and obese women. Methods: Thirtyoverweight and obese women participated in this study with body mass index > 25 kg/m2andwaist circumference ≥ 85 cm. Their ages ranged from 28 - 40 years old.The subjects were excluded if they have diabetes, abdominal infection diseases or any physical limitation restricting exercise ability. They were randomly allocated into two equal groups; group I and group II. Group I received vacuum therapy sessions (by the use of LPG device in addition to aerobic exercise training. Group II received abdominal exercises in addition to the same aerobic exercisesgiven to group I. This study was extended for successive 8 weeks (3 sessions/ week. All subjects were assessed for thickness ofnthe abdominal skin fold, waist circumference and body mass index. Results: The results of this study showeda significant difference between group I and group II post-interventionas regarding to the mean values of waist circumference and abdominal skin fold thickness (p<0.05. Conclusion: It can be concluded that aerobic exercises combined with vacuum therapy (for three sessions/week for successive 8 weeks have a positive effect on women with abdominal obesity in terms of reducing waist circumference and abdominal skin fold thickness.

  19. Síndrome compartimental abdominal

    Directory of Open Access Journals (Sweden)

    Misael Guzmán Nápoles

    Full Text Available Desde el siglo XIX se conocen los efectos negativos del aumento de la presión intraabdominal, pero no se le prestó la debida atención a este trastorno hasta la última década del pasado siglo y la primera del actual. En este artículo exponemos las definiciones de los términos presión intrabdominal, hipertensión intrabdominal y síndrome compartimental abdominal, que fueron tomadas por consenso y aprobadas por la World Society of the Abdominal Compartment Syndrome. En nuestro medio, para el diagnóstico de la hipertensión intrabdominal y del síndrome compartimental abdominal se requiere medir la presión intrabdominal, secundariamente la presión de perfusión abdominal y se deben correlacionar estos datos con signos de deterioro clínico en el paciente. Las medidas terapéuticas médicas en relación con el síndrome compartimental abdominal son limitadas; cuando este es sintomático la descompresión abdominal es el tratamiento ya establecido. Enfatizamos en que el diagnóstico temprano de la hipertensión intrabdominal y del síndrome compartimental abdominal contribuyen a disminuir el desarrollo de un síndrome de disfunción múltiple de órganos y por tanto a reducir la mortalidad en estos pacientes. Con el objetivo de actualizar los conocimientos sobre hipertensión intrabdominal y síndrome compartimental abdominal, su diagnóstico y tratamiento, realizamos una minuciosa revisión actualizada de diversos artículos referentes al síndrome compartimental abdominal, tanto en el ámbito nacional como internacional.

  20. An abdominal tuberculosis case mimicking an abdominal mass

    African Journals Online (AJOL)

    year-old child with an unusual clinical presentation ... Keywords: abdominal tuberculosis, child, diagnosis. Departments of .... vomiting, gas distension, diarrhea, or constipation), whereas ... senteric echo in the acute stage with peritoneal involve-.

  1. A single-ensemble clutter rejection method based on the analytic geometry for ultrasound color flow imaging.

    Science.gov (United States)

    You, Wei; Wang, Yuanyuan

    2011-11-01

    In ultrasound color flow imaging (CFI), the single-ensemble eigen-based filters can reject clutter components using each slow-time ensemble individually. They have shown excellent spatial adaptability. This article proposes a novel clutter rejection method called the single-ensemble geometry filter (SGF), which is derived from an analytic geometry perspective. If the transmitted pulse number M equals two, the clutter component distribution on a two-dimensional (2-D) plane will be similar to a tilted ellipse. Therefore, the direction of the major axis of the ellipse can be used as the first principal component of the autocorrelation matrix estimated from multiple ensembles. Then the algorithm is generalized from 2-D to a higher dimensional space by using linear algebra representations of the ellipse. Comparisons have been made with the high-pass filter (HPF), the Hankel-singular value decomposition (SVD) filter and the recursive eigen-decomposition (RED) method using both simulated and human carotid data. Results show that compared with HPF and Hankel-SVD, the proposed filter causes less bias on the velocity estimation when the clutter velocity is close to that of the blood flow. On the other hand, the proposed filter does not need to update the autocorrelation matrix and can achieve better spatial adaptability than the RED.

  2. Analysis of measured L-band airborne land clutter from the Western Cape region of South Africa

    CSIR Research Space (South Africa)

    De Witt, JJ

    2014-10-01

    Full Text Available This paper presents backscatter analysis of L-band land clutter data, measured from an airborne platform, over various terrain types encountered in the Western Cape region of South Africa. The data processing steps are described and the backscatter...

  3. Economics of abdominal wall reconstruction.

    Science.gov (United States)

    Bower, Curtis; Roth, J Scott

    2013-10-01

    The economic aspects of abdominal wall reconstruction are frequently overlooked, although understandings of the financial implications are essential in providing cost-efficient health care. Ventral hernia repairs are frequently performed surgical procedures with significant economic ramifications for employers, insurers, providers, and patients because of the volume of procedures, complication rates, the significant rate of recurrence, and escalating costs. Because biological mesh materials add significant expense to the costs of treating complex abdominal wall hernias, the role of such costly materials needs to be better defined to ensure the most cost-efficient and effective treatments for ventral abdominal wall hernias.

  4. A positioning system with no line-of-sight restrictions for cluttered environments

    Science.gov (United States)

    Prigge, Eric A.

    Accurate sensing of vehicle location and attitude is a fundamental requirement in many mobile-robot applications, but is a very challenging problem in the cluttered and unstructured environment of the real world. Many existing indoor positioning systems are limited in workspace and robustness because they require clear lines of sight or do not provide absolute, drift-free measurements. Examples include overhead vision systems, where an unobstructed view must be maintained between robot and camera, and inertial systems, where the measurements drift over time. The research presented in this dissertation provides a new location- and attitude-sensing system designed specifically to meet the challenges of operation in a realistic, cluttered indoor environment, such as that of an office building or warehouse. The system is not limited by line-of-sight restrictions and produces drift-free measurements throughout a three-dimensional operating volume that can span a large building. Accuracy of several centimeters and a few degrees is delivered at 10 Hz, and any number of the small sensor units can be in operation, all providing estimates in a common reference frame. This positioning system is based on extremely-low-frequency magnetic fields, which have excellent characteristics for penetrating line-of-sight obstructions. Beacons located throughout the workspace create the low-level fields. A sensor unit on the mobile robot samples the local magnetic field and processes the measurements to determine its location and attitude. This research overcomes limitations in existing magnetic-based systems. The design of the signal structure, based on pseudorandom codes, enables the use of multiple, distributed L-beacons and greatly expands coverage volume. The development of real-time identification and correction methods mitigates the impact of distortions caused by materials in the environment. A novel solution algorithm combats both challenges, providing increased coverage volume

  5. OPTIMAL SELECTION OF THE CA-CFAR ADJUSTMENT FACTOR FOR K POWER SEA CLUTTER WITH STATISTICAL VARIATIONS

    Directory of Open Access Journals (Sweden)

    José Raúl Machado Fernández

    2017-01-01

    Full Text Available La presencia de la señal interferente de clutter marino establece limitaciones en la calidad de la detección de radar en ambientes costeros y de alta mar. El procesador CA-CFAR es la solución clásica para detectar blancos de radar. Usualmente mantiene su factor de ajuste constante todo el período de operación. Como consecuencia, el esquema no toma en consideración las variaciones estadísticas de la señal de fondo cuando realiza la discriminación del clutter . Para resolver este problema, los autores realizaron un procesamiento intensivo de 40 millones de muestras de clutter de intensidad, generadas en computadora a través de MATLAB. Como resultado, encontraron los valores óptimos del factor de ajuste a ser aplicados para 40 posibles estados estadísticos del clutter , sugiriendo el uso de la arquitectura CA-CFAR con un factor de ajuste variable. Adicionalmente, fue llevado a cabo un ajuste de curvas, obteniéndose expresiones matemáticas que generalizan los resultados en todo el intervalo de considerado de estados estadísticos del clutter . Los experimentos se ejecutaron con un CA-CFAR de 64 celdas y apuntaron a encontrar los valores del factor de ajuste para tres probabilidades de falsa alarma comunes. La distribución K fue elegida como el modelo usado para el clutter , gracias a su amplia popularidad. Este artículo facilita el manejo de la distribución K de intensidad, evitando el uso de funciones Gamma y Bessel, comúnmente encontradas en desarrollos relacionados con el modelo K. Además, fueron cumplidos los requerimientos necesarios para construir un detector adaptativo en clutter de potencia K con conocimiento previo del parámetro de forma. Al mismo tiempo, fueron dadas varias recomendaciones para continuar el desarrollo de una solución más general que también incluirá la estimación del parámetro de forma.

  6. Abdominal aortic feminism.

    Science.gov (United States)

    Mortimer, Alice Emily

    2014-11-14

    A 79-year-old woman presented to a private medical practice 2 years previously for an elective ultrasound screening scan. This imaging provided the evidence for a diagnosis of an abdominal aortic aneurysm (AAA) to be made. Despite having a number of recognised risk factors for an AAA, her general practitioner at the time did not follow the guidance set out by the private medical professional, that is, to refer the patient to a vascular specialist to be entered into a surveillance programme and surgically evaluated. The patient became symptomatic with her AAA, was admitted to hospital and found to have a tender, symptomatic, 6 cm leaking AAA. She consented for an emergency open AAA repair within a few hours of being admitted to hospital, despite the 50% perioperative mortality risk. The patient spent 4 days in intensive care where she recovered well. She was discharged after a 12 day hospital stay but unfortunately passed away shortly after her discharge from a previously undiagnosed gastric cancer. 2014 BMJ Publishing Group Ltd.

  7. Micromanaging Abdominal Aortic Aneurysms

    Directory of Open Access Journals (Sweden)

    Lars Maegdefessel

    2013-07-01

    Full Text Available The contribution of abdominal aortic aneurysm (AAA disease to human morbidity and mortality has increased in the aging, industrialized world. In response, extraordinary efforts have been launched to determine the molecular and pathophysiological characteristics of the diseased aorta. This work aims to develop novel diagnostic and therapeutic strategies to limit AAA expansion and, ultimately, rupture. Contributions from multiple research groups have uncovered a complex transcriptional and post-transcriptional regulatory milieu, which is believed to be essential for maintaining aortic vascular homeostasis. Recently, novel small noncoding RNAs, called microRNAs, have been identified as important transcriptional and post-transcriptional inhibitors of gene expression. MicroRNAs are thought to “fine tune” the translational output of their target messenger RNAs (mRNAs by promoting mRNA degradation or inhibiting translation. With the discovery that microRNAs act as powerful regulators in the context of a wide variety of diseases, it is only logical that microRNAs be thoroughly explored as potential therapeutic entities. This current review summarizes interesting findings regarding the intriguing roles and benefits of microRNA expression modulation during AAA initiation and propagation. These studies utilize disease-relevant murine models, as well as human tissue from patients undergoing surgical aortic aneurysm repair. Furthermore, we critically examine future therapeutic strategies with regard to their clinical and translational feasibility.

  8. FIBRINOLYTIC-ACTIVITY IN THE ABDOMINAL-CAVITY OF RATS WITH FECAL PERITONITIS

    NARCIS (Netherlands)

    van Goor, Harry; de Graaf, JS; Sluiter, WJ; van der Meer, J; Bom, VJJ; Bleichrodt, RP

    1994-01-01

    Generalized peritonitis causes a reduction in abdominal fibrinolytic activity, resulting in persistence of intraabdominal fibrin with subsequent adhesion and abscess formation. The activities of tissue plasminogen activator (tPA) and plasminogen activator inhibitor (PAI) were measured in the periton

  9. FIBRINOLYTIC-ACTIVITY IN THE ABDOMINAL-CAVITY OF RATS WITH FECAL PERITONITIS

    NARCIS (Netherlands)

    van Goor, Harry; de Graaf, JS; Sluiter, WJ; van der Meer, J; Bom, VJJ; Bleichrodt, RP

    1994-01-01

    Generalized peritonitis causes a reduction in abdominal fibrinolytic activity, resulting in persistence of intraabdominal fibrin with subsequent adhesion and abscess formation. The activities of tissue plasminogen activator (tPA) and plasminogen activator inhibitor (PAI) were measured in the periton

  10. Effects of Cryolipolysis on Abdominal Adiposity

    Directory of Open Access Journals (Sweden)

    Patricia Froes Meyer

    2016-01-01

    Full Text Available Cryolipolysis is a noninvasive technique of localized fat reduction. Controlled cold exposure is performed in the selective destruction of fat cells. The aim of this study was to investigate the effects of cryolipolysis on adipocytes elimination through histological and sonographic analyses. This study reports the case of a 46-year-old female patient, with complaint of localized abdominal fat and in the preoperative period of abdominoplasty. The patient was submitted to a single 60-minute application of cryolipolysis, temperature of −5°C, on the hypogastrium area, 5 cm below the umbilicus. To study the effects of this treatment, ultrasound images taken before the session and 7, 15, 30, and 45 days after the therapy were analysed. After the abdominoplasty, parts of the treated and the untreated withdrawn abdominal tissues were evaluated macro- and microscopically. In ultrasound images, as well as in macroscopic and histological analyses, significant adipocytes destruction was detected, with consequent fat layer reduction and integrity of areas that were adjacent to the treated tissue. The presence of fibrosis observed during therapy and acknowledged through performed analyses encourages further studies to clarify such finding.

  11. [Monitoring of intra-abdominal pressure and abdominal perfusion pressure in urgent abdominal surgery].

    Science.gov (United States)

    Raĭbuzhis, E N; Fot, E V; Gaĭdukov, K M; Kirov, M Iu

    2014-01-01

    To evaluate the changes in intra-abdominal pressure (IAP) and abdominal perfusion pressure (APP) during perioperative period in urgent abdominal surgery and to assess the relationship of these parameters with gas exchange and tissue perfusion. Twenty-four patients undergoing emergency abdominal surgery were enrolled into a prospective observational study. We recorded IAP APP, mean arterial pressure, arterial and venous blood gases after induction of anesthesia, at the end of surgery, and 6, 12, 48 and 72 h postoperatively. LAP was measured by nasogastric tube using CiMON monitor (Pulsion Medical Systems, Germany). In addition, we studied the relationship of IAP and APP with blood gases parameters. We observed perioperative increase of IAP (> 12 mm Hg) in 75% of enrolled patients, tendency to postoperative rise of IAP and transient increase of arterial lactate at 6 h after surgery. APP remained within normal values. We found positive correlation of APP with PaO2/FiO2 and ScvO2 at 72 hours after surgery. Transient perioperative increase of IAP was observed in 75% patients undergoing urgent abdominal surgery; however in parallel with intensive care the abdominal perfusion pressure remained within normal values. Abdominal perfusion is related with arterial oxygenation and central venous saturation.

  12. An X-ray scatter system for material identification in cluttered objects: A Monte Carlo simulation study

    Energy Technology Data Exchange (ETDEWEB)

    Lakshmanan, Manu N. [Ravin Advanced Imaging Laboratories, Dept. of Radiology, Duke University Medical Center, Durham, NC (United States); Kapadia, Anuj J., E-mail: anuj.kapadia@duke.edu [Ravin Advanced Imaging Laboratories, Dept. of Radiology, Duke University Medical Center, Durham, NC (United States); Sahbaee, Pooyan [Ravin Advanced Imaging Laboratories, Dept. of Radiology, Duke University Medical Center, Durham, NC (United States); Dept. of Physics, NC State University, Raleigh, NC (United States); Wolter, Scott D. [Dept. of Physics, Elon University, Elon, NC (United States); Harrawood, Brian P. [Ravin Advanced Imaging Laboratories, Dept. of Radiology, Duke University Medical Center, Durham, NC (United States); Brady, David [Dept. of Electrical and Computer Engineering, Duke University, Durham, NC (United States); Samei, Ehsan [Ravin Advanced Imaging Laboratories, Dept. of Radiology, Duke University Medical Center, Durham, NC (United States); Dept. of Electrical and Computer Engineering, Duke University, Durham, NC (United States)

    2014-09-15

    The analysis of X-ray scatter patterns has been demonstrated as an effective method of identifying specific materials in mixed object environments, for both biological and non-biological applications. Here we describe an X-ray scatter imaging system for material identification in cluttered objects and investigate its performance using a large-scale Monte Carlo simulation study of one-thousand objects containing a broad array of materials. The GEANT4 Monte Carlo source code for Rayleigh scatter physics was modified to model coherent scatter diffraction in bulk materials based on experimentally measured form factors for 33 materials. The simulation was then used to model coherent scatter signals from a variety of targets and clutter (background) materials in one thousand randomized objects. The resulting scatter images were used to characterize four parameters of the imaging system that affected its ability to identify target materials: (a) the arrangement of materials in the object, (b) clutter attenuation, (c) type of target material, and (d) the X-ray tube current. We found that the positioning of target materials within the object did not significantly affect their detectability; however, a strong negative correlation was observed between the target detectability and the clutter attenuation of the object. The imaging signal was also found to be relatively invariant to increases in X-ray tube current above 1 mAs for most materials considered in the study. This work is the first Monte Carlo study to our knowledge of a large population of cluttered object of an X-ray scatter imaging system for material identification and lays the foundation for large-scale studies of the effectiveness of X-ray scatter imaging systems for material identification in complex samples.

  13. An X-ray scatter system for material identification in cluttered objects: A Monte Carlo simulation study

    Science.gov (United States)

    Lakshmanan, Manu N.; Kapadia, Anuj J.; Sahbaee, Pooyan; Wolter, Scott D.; Harrawood, Brian P.; Brady, David; Samei, Ehsan

    2014-09-01

    The analysis of X-ray scatter patterns has been demonstrated as an effective method of identifying specific materials in mixed object environments, for both biological and non-biological applications. Here we describe an X-ray scatter imaging system for material identification in cluttered objects and investigate its performance using a large-scale Monte Carlo simulation study of one-thousand objects containing a broad array of materials. The GEANT4 Monte Carlo source code for Rayleigh scatter physics was modified to model coherent scatter diffraction in bulk materials based on experimentally measured form factors for 33 materials. The simulation was then used to model coherent scatter signals from a variety of targets and clutter (background) materials in one thousand randomized objects. The resulting scatter images were used to characterize four parameters of the imaging system that affected its ability to identify target materials: (a) the arrangement of materials in the object, (b) clutter attenuation, (c) type of target material, and (d) the X-ray tube current. We found that the positioning of target materials within the object did not significantly affect their detectability; however, a strong negative correlation was observed between the target detectability and the clutter attenuation of the object. The imaging signal was also found to be relatively invariant to increases in X-ray tube current above 1 mAs for most materials considered in the study. This work is the first Monte Carlo study to our knowledge of a large population of cluttered object of an X-ray scatter imaging system for material identification and lays the foundation for large-scale studies of the effectiveness of X-ray scatter imaging systems for material identification in complex samples.

  14. Children's (Pediatric) Abdominal Ultrasound Imaging

    Medline Plus

    Full Text Available ... imaging can also: help a physician determine the source of abdominal pain, such as gallstones, kidney stones, ... Send us your feedback Did you find the information you were looking for? Yes No Please type ...

  15. Children's (Pediatric) Abdominal Ultrasound Imaging

    Medline Plus

    Full Text Available ... children. Except for traumatic injury, appendicitis is the most common reason for emergency abdominal surgery. Ultrasound imaging ... of page How is the procedure performed? For most ultrasound exams, you will be positioned lying face- ...

  16. Intra-abdominal tuberculous peritonitis

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, G.; Ahlhelm, F.; Altmeyer, K.; Kramann, B. [Dept. of Diagnostic Radiology, University Hospital, Homburg (Germany); Hennes, P. [Dept. of Pediatrics, University Hospital, Homburg (Germany); Pueschel, W. [Dept. of Pathology, University Hospital, Homburg (Germany); Karadiakos, N. [Dept. of Pediatric Surgery, University Hospital, Homburg (Germany)

    2001-07-01

    We report the case of a 15-year-old boy suffering from progressive dyspnea on exertion and painful abdominal protrusion. Final diagnosis of intra-abdominal tuberculosis (TB), including lymphadenopathy and abdominal abscess formation, was made following elective laparotomy. This type of disease is a rare manifestation of extrapulmonary tuberculosis. The imaging findings in unenhanced and contrast-enhanced MRI and laparoscopic images are presented. Differential diagnosis of abdominal abscess formation and other fungal or bacteriological infections, as well as the imaging findings of this type of lesion, are discussed. This case demonstrates that atypical manifestation of TB may remain unrecognized; thus, awareness of this kind of manifestation of tuberculosis may prevent patients from being subjected to inappropriate therapies. (orig.)

  17. Children's (Pediatric) Abdominal Ultrasound Imaging

    Medline Plus

    Full Text Available ... located within a child's abdomen. A Doppler ultrasound study may be part of a child's abdominal ultrasound ... pain from the procedure. If a Doppler ultrasound study is performed, your child may actually hear pulse- ...

  18. Children's (Pediatric) Abdominal Ultrasound Imaging

    Medline Plus

    Full Text Available ... of page What are some common uses of the procedure? Abdominal ultrasound imaging is performed to evaluate ... for ultrasound examinations. top of page What does the equipment look like? Ultrasound scanners consist of a ...

  19. Disseminated Intra-Abdominal Hydatidosis

    Science.gov (United States)

    Concha, Fátima; Maguiña, Ciro; Seas, Carlos

    2013-01-01

    We present the case of a 26-year-old male Peruvian patient who presented with disseminated intra-abdominal hydatidosis. The patient was treated with surgical removal of the cysts and prolonged medical treatment with albendazole. PMID:24006293

  20. Abdominal Actinomycetoma With Lymphnode Involvement

    Directory of Open Access Journals (Sweden)

    Damisetty Rajetha

    2004-01-01

    Full Text Available Actinomycotic mycetoma of the anterior abdominal wall with inguinal lymphnode involvement, an exceedingly rare entity is described here with mycological histological features. Remarkable therapeutic response was noted with Welsh regimen.

  1. Children's (Pediatric) Abdominal Ultrasound Imaging

    Medline Plus

    Full Text Available ... your doctor if there are specific instructions for eating and drinking prior to the exam. Your child ... for laboratory testing help detect the presence and cause of an apparent enlarged abdominal organ identify the ...

  2. Children's (Pediatric) Abdominal Ultrasound Imaging

    Medline Plus

    Full Text Available ... valuable for evaluating abdominal, pelvic or scrotal pain in children. Preparation will depend on the type of ... examinations do not use ionizing radiation (as used in x-rays ), thus there is no radiation exposure ...

  3. Children's (Pediatric) Abdominal Ultrasound Imaging

    Medline Plus

    Full Text Available ... of an apparent enlarged abdominal organ identify the location of abnormal fluid in the abdomen help determine ... places the transducer on the skin in various locations, sweeping over the area of interest or angling ...

  4. Children's (Pediatric) Abdominal Ultrasound Imaging

    Medline Plus

    Full Text Available ... collects the sounds that bounce back and a computer then uses those sound waves to create an ... located within a child's abdomen. A Doppler ultrasound study may be part of a child's abdominal ultrasound ...

  5. Children's (Pediatric) Abdominal Ultrasound Imaging

    Medline Plus

    Full Text Available ... ultrasound images are captured in real-time, they can show the structure and movement of the body's ... kidneys bladder testicles ovaries uterus Abdominal ultrasound images can be used to help diagnose appendicitis in children. ...

  6. Children's (Pediatric) Abdominal Ultrasound Imaging

    Medline Plus

    Full Text Available ... child's abdominal ultrasound examination. Doppler ultrasound , also called color Doppler ultrasonography, is a special ultrasound technique that ... and processes the sounds and creates graphs or color pictures that represent the flow of blood through ...

  7. Children's (Pediatric) Abdominal Ultrasound Imaging

    Medline Plus

    Full Text Available ... of page What are some common uses of the procedure? Abdominal ultrasound imaging is performed to evaluate ... for ultrasound examinations. top of page What does the ultrasound equipment look like? Ultrasound scanners consist of ...

  8. Towards automatic indoor reconstruction of cluttered building rooms from point clouds

    Science.gov (United States)

    Previtali, M.; Barazzetti, L.; Brumana, R.; Scaioni, M.

    2014-05-01

    Terrestrial laser scanning is increasingly used in architecture and building engineering for as-built modelling of large and medium size civil structures. However, raw point clouds derived from laser scanning survey are generally not directly ready for generation of such models. A manual modelling phase has to be undertaken to edit and complete 3D models, which may cover indoor or outdoor environments. This paper presents an automated procedure to turn raw point clouds into semantically-enriched models of building interiors. The developed method mainly copes with a geometric complexity typical of indoor scenes with prevalence of planar surfaces, such as walls, floors and ceilings. A characteristic aspect of indoor modelling is the large amount of clutter and occlusion that may characterize any point clouds. For this reason the developed reconstruction pipeline was designed to recover and complete missing parts in a plausible way. The accuracy of the presented method was evaluated against traditional manual modelling and showed comparable results.

  9. Resolved target detection in clutter using correlated, dual-band imagery

    Science.gov (United States)

    Stotts, Larry B.

    2015-10-01

    This paper develops a log-likelihood ratio test statistic for resolved target detection in dual-band imagery because the previous work indicates that most of the processing gains come from processing just two bands. Simple, closed-form equations for the closed-form probabilities of false alarm and detection are given. A computer simulation validates the theory. A constant false alarm rate version of the theory is applied to real available multiband data with quasi-resolved target sets and fixed clutter noise. The results show very reasonable performance in target detectability using three sets of correlated dual-band images. Finally, this paper shows that the resolved target detection problem depends on the weighted difference between the dual-band target contrasts. The theoretical development reaffirms that the signal-to-noise ratio or contrast-to-noise ratio is approximately the weighted difference squared, divided by the normalized total image noise variance.

  10. Radar Constant-Modulus Waveform Design with Prior Information of the Extended Target and Clutter.

    Science.gov (United States)

    Yue, Wenzhen; Zhang, Yan; Liu, Yimin; Xie, Jingwen

    2016-06-17

    Radar waveform design is of great importance for radar system performances and has drawn considerable attention recently. Constant modulus is an important waveform design consideration, both from the point of view of hardware realization and to allow for full utilization of the transmitter's power. In this paper, we consider the problem of constant-modulus waveform design for extended target detection with prior information about the extended target and clutter. At first, we propose an arbitrary-phase unimodular waveform design method via joint transmitter-receiver optimization. We exploit a semi-definite relaxation technique to transform an intractable non-convex problem into a convex problem, which can then be efficiently solved. Furthermore, quadrature phase shift keying waveform is designed, which is easier to implement than arbitrary-phase waveforms. Numerical results demonstrate the effectiveness of the proposed methods.

  11. Door recognition in cluttered building interiors using imagery and lidar data

    Science.gov (United States)

    Díaz-Vilariño, L.; Martínez-Sánchez, J.; Lagüela, S.; Armesto, J.; Khoshelham, K.

    2014-06-01

    Building indoors reconstruction is an active research topic due to the importance of the wide range of applications to which they can be subjected, from architecture and furniture design, to movies and video games editing, or even crime scene investigation. Among the constructive elements defining the inside of a building, doors are important entities in applications like routing and navigation, and their automated recognition is advantageous e.g. in case of large multi-storey buildings with many office rooms. The inherent complexity of the automation of the recognition process is increased by the presence of clutter and occlusions, difficult to avoid in indoor scenes. In this work, we present a pipeline of techniques used for the reconstruction and interpretation of building interiors using information acquired in the form of point clouds and images. The methodology goes in depth with door detection and labelling as either opened, closed or furniture (false positive)

  12. Updates on abdominal desmoid tumors

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Desmoid tumor is a monoclonal, fibroblastic proliferation arising in musculoaponeurotic structures. This connective tissue hyperplasia infiltrates locally, recurs frequentiy after resection but does not metastasize. Abdominal desmoid occurs sporadically, in association with some familial syndromes and often represents a clinical dilemma for surgeons. The enigmatic biology and anatomical location of abdominal desmoids make treatment recommendations difficult. This distinct pathological entity is reviewed with a specific focus on aetiology and management.

  13. The Complexity of Background Clutter Affects Nectar Bat Use of Flower Odor and Shape Cues.

    Directory of Open Access Journals (Sweden)

    Nathan Muchhala

    Full Text Available Given their small size and high metabolism, nectar bats need to be able to quickly locate flowers during foraging bouts. Chiropterophilous plants depend on these bats for their reproduction, thus they also benefit if their flowers can be easily located, and we would expect that floral traits such as odor and shape have evolved to maximize detection by bats. However, relatively little is known about the importance of different floral cues during foraging bouts. In the present study, we undertook a set of flight cage experiments with two species of nectar bats (Anoura caudifer and A. geoffroyi and artificial flowers to compare the importance of shape and scent cues in locating flowers. In a training phase, a bat was presented an artificial flower with a given shape and scent, whose position was constantly shifted to prevent reliance on spatial memory. In the experimental phase, two flowers were presented, one with the training-flower scent and one with the training-flower shape. For each experimental repetition, we recorded which flower was located first, and then shifted flower positions. Additionally, experiments were repeated in a simple environment, without background clutter, or a complex environment, with a background of leaves and branches. Results demonstrate that bats visit either flower indiscriminately with simple backgrounds, with no significant difference in terms of whether they visit the training-flower odor or training-flower shape first. However, in a complex background olfaction was the most important cue; scented flowers were consistently located first. This suggests that for well-exposed flowers, without obstruction from clutter, vision and/or echolocation are sufficient in locating them. In more complex backgrounds, nectar bats depend more heavily on olfaction during foraging bouts.

  14. Path Planning for Non-Circular, Non-Holonomic Robots in Highly Cluttered Environments.

    Science.gov (United States)

    Samaniego, Ricardo; Lopez, Joaquin; Vazquez, Fernando

    2017-08-15

    This paper presents an algorithm for finding a solution to the problem of planning a feasible path for a slender autonomous mobile robot in a large and cluttered environment. The presented approach is based on performing a graph search on a kinodynamic-feasible lattice state space of high resolution; however, the technique is applicable to many search algorithms. With the purpose of allowing the algorithm to consider paths that take the robot through narrow passes and close to obstacles, high resolutions are used for the lattice space and the control set. This introduces new challenges because one of the most computationally expensive parts of path search based planning algorithms is calculating the cost of each one of the actions or steps that could potentially be part of the trajectory. The reason for this is that the evaluation of each one of these actions involves convolving the robot's footprint with a portion of a local map to evaluate the possibility of a collision, an operation that grows exponentially as the resolution is increased. The novel approach presented here reduces the need for these convolutions by using a set of offline precomputed maps that are updated, by means of a partial convolution, as new information arrives from sensors or other sources. Not only does this improve run-time performance, but it also provides support for dynamic search in changing environments. A set of alternative fast convolution methods are also proposed, depending on whether the environment is cluttered with obstacles or not. Finally, we provide both theoretical and experimental results from different experiments and applications.

  15. Common abdominal emergencies in children.

    Science.gov (United States)

    D'Agostino, James

    2002-02-01

    Because young children often present to EDs with abdominal complaints, emergency physicians must have a high index of suspicion for the common abdominal emergencies that have serious sequelae. At the same time, they must realize that less serious causes of abdominal symptoms (e.g., constipation or gastroenteritis) are also seen. A gentle yet thorough and complete history and physical examination are the most important diagnostic tools for the emergency physician. Repeated examinations and observation are useful tools. Physicians should listen carefully to parents and their children, respect their concerns, and honor their complaints. Ancillary tests are inconsistent in their value in assessing these complaints. Abdominal radiographs can be normal in children with intussusception and even malrotation and early volvulus. Unlike the classic symptoms seen in adults, young children can display only lethargy or poor feeding in cases of appendicitis or can appear happy and playful between paroxysmal bouts of intussusception. The emergency physician therefore, must maintain a high index of suspicion for serious pathology in pediatric patients with abdominal complaints. Eventually, all significant abdominal emergencies reveal their true nature, and if one can be patient with the child and repeat the examinations when the child is quiet, one will be rewarded with the correct diagnosis.

  16. A Real-Time Nowcast/Forecast System for Radar Electrojet Clutter Driven by Global Assimilative Models of the Ionosphere

    Science.gov (United States)

    Carrano, C. S.; Alcala, C. M.; Liang, P.; Groves, K. M.; Donatelli, D. E.; Daniell, R. E.

    2006-12-01

    The Space-Based Radar Ionospheric Effects Simulation (SBR-IES) tool was developed to predict the degrading effects of the ionosphere on the performance of space-based radar systems. This presentation focuses on the technique used by the SBR-IES to predict radar electrojet clutter. The term electrojet clutter refers to backscatter from electron density irregularities that develop in response to unstable (two-stream) current systems in the auroral and equatorial electrojets. The two-stream instability is a dominant mechanism for the generation of electrojet clutter for radars operating in and above the VHF frequency band. The effects of these irregularities on the performance of ground- and space-based radars are discussed. The ionospheric clutter predictions are made using the approach developed for the Comprehensive E-Region Auroral Clutter (CERAC) model by SRI International and Rome Laboratory. The threshold velocity required for the generation of ionospheric irregularities by the two-stream instability is computed using nonlinear plasma wave theory. The streaming velocity, or the relative velocity between the electrons and ions, is calculated based on the ExB drift. When the streaming velocity exceeds the threshold, the clutter strength is estimated using an empirical relationship involving the radar frequency, electron density, magnetic aspect angle, and flow angle. A uniformly distributed layer of scattering irregularities is assumed. The ionospheric clutter predictions provided by the initial version of the SBR-IES tool were based on a climatological, or average, description of ionospheric conditions at the time of observation, driven by Kp, Ap, and the 10.7 cm solar flux. This approach, while having the advantage of requiring only a few geophysical input parameters to run, is limited by the use of overly simplified (smoothed) climatological models for the electric field, as well as electron, ion, and neutral densities and temperatures within the E

  17. Abdominal neurenteric cyst

    Institute of Scientific and Technical Information of China (English)

    Radoje (C)olovi(c); MarJan Micev; Miodrag Jovanovi(c); Slavko Mati(c); Nikica Grubor; Henry Dushan E Atkinson

    2008-01-01

    immunoexpression, and the respiratory epithelium revealed a CK8 and CK18 immunoprofile without CK 10/13 positive elements, though neither CEA or AFP positive cells were found. To our knowledge, this is the first reported case of an abdominally located neurenteric cyst with no associated spinal anomalies.

  18. A clinical dilemma: abdominal tuberculosis

    Institute of Scientific and Technical Information of China (English)

    Oya Uygur-Bayramicli; G(u)l Dabak; Resat Dabak

    2003-01-01

    AIM: To evaluate the clinical, radiological and microbiological properties of abdominal tuberculosis (TB) and to discuss methods needed to get the diagnosis.METHODS: Thirty-one patients diagnosed as abdominal TB between March 1998 and December 2001 at the Gastroenterology Department of Kartal State Hospital,Istanbul, Turkey were evaluated prospectively. Complete physical examination, medical and family history, blood count erythrocyte sedimentation rate, routine biochemical tests,Mantoux skin test, chest X-ray and abdominal ultrasonography (USG) were performed in all cases, whereas microbiological examination of ascites, upper gastrointestinal endoscopy, colonoscopy or barium enema, abdominal tomography, mediastinoscopy, laparoscopy or laparotomy were done when needed.RESULTS: The median age of patients (14 females, 17males) was 34.2 years (range 15-65 years). The most frequent symptoms were abdominal pain and weight loss.Eleven patients had active pulmonary TB. The most common abdominal USG findings were ascites and hepatomegaly. Ascitic fluid analysis performed in 13 patients was found to be exudative and acid resistant bacilli were present in smear and cultured only in one patient with BacTec (3.2 %). Upper gastrointestinal endoscopy yielded nonspecific findings in 16 patients. Colonoscopy performed in 20 patients showed ulcers in 9 (45 %), nodules in 2 (10 %)and, stricture, polypoid lesions, granulomatous findings in terminal ileum and rectal fistula each in one patient (5 %).Laparoscopy on 4 patients showed dilated bowel loops,thickening in the mesentery, multiple ulcers and tubercles on the peritoneum. Patients with abdominal TB were divided into three groups according to the type of involvement.Fifteen patients (48 %) had intestinal TB, L1 patients (35.2 %) had tuberculous peritonitis and 5 (16.8 %)tuberculous lymphadenitis. The diagnosis of abdominal TB was confirmed microbiologically in 5 (16 %) and histopathologically in 19 patients (60.8 %). The

  19. [Abdominal pregnancy care. Case report].

    Science.gov (United States)

    Morales Hernández, Sara; Díaz Velázquez, Mary Flor; Puello Tamara, Edgardo; Morales Hernández, Jorge; Basavilvazo Rodríguez, Maria Antonia; Cruz Cruz, Polita del Rocío; Hernández Valencia, Marcelino

    2008-10-01

    Abdominal pregnancies are the implantation of gestation in some of the abdominal structures. This kind of pregnancies represents sevenfold maternal death risk than tubarian ectopic pregnancies, and 90-fold death risk than normal ones. Previous cases have erroneously reported as abscess in Douglas punch, and frequently result in obitus or postnatal deaths. We report a case of a patient with 27 years old, and diagnosis of 25.2 weeks of pregnancy, prior placenta and anhidramnios, referred due to difficult in uterine contour delimitation, easy palpation of fetal parts, cephalic pole in left hypochondrious and presence of mass in hypogastria, no delimitations, pain with mobilization, no transvaginal bleed and fetal movements. Interruption of pregnancy is decided by virtue of severe oligohidramnios, retardation in fetal intrabdominal growth, and recurrent maternal abdominal pain. Surgical intervention was carried out for resolution of the obstetrical event, in which was found ectopic abdominal pregnancy with bed placental in right uterine horn that corresponded to a pregnancy of 30 weeks of gestation. Abdominal pregnancy is still a challenge for obstetrics due to its diagnosis and treatment. Early diagnosis is oriented to prevent an intrabdominal hemorrhage that is the main maternal cause of mortality.

  20. Abdominal obesity, cardiometabolic risk and endocannabinoid system

    Directory of Open Access Journals (Sweden)

    G. Bittolo Bon

    2013-05-01

    Full Text Available Abdominal obesity is the most prevalent manifestation of metabolic syndrome and is of central importance in the definition of global cardiometabolic risk. Visceral adipose tissue releases a large number of bioactive mediators, which influence body weight homeostasis, insulin resistance, alterations in lipids, blood pressure, coagulation, fibrinolysis and inflammation, leading to increased risk of cardiovascular events and of type 2 diabetes. Lifestyle modification is the first-line approach to the management of abdominal obesity and metabolic syndrome. However for patients at higher risk, who cannot achieve an appreciable reduction in weight and in global cardiometabolic risk with lifestyle modification alone, an adjunctive long term pharmacotherapy should be considered. The endocannabinoid system activity regulates food intake and metabolic factors through cannabinoid-1 (CB1 receptor located in multiple sites, including hypothalamus and limbic forebrain, adipose tissue, skeletal muscle, liver and the gastrointestinal tract. Evidence suggests that CB1 receptor blockade offers a novel therapeutic strategy. Data from four phase III trials suggest that rimonabant, the first cannabinoid receptor inhibitor, modulates cardiometabolic risk factors, both through its impact on body weight and metabolic parameters such as HDL-cholesterol, tryglicerides, Hb1Ac, through direct pathways that are not related to weight loss.

  1. Abdominal wall hernia and pregnancy

    DEFF Research Database (Denmark)

    Jensen, K K; Henriksen, N A; Jorgensen, L N

    2015-01-01

    PURPOSE: There is no consensus as to the treatment strategy for abdominal wall hernias in fertile women. This study was undertaken to review the current literature on treatment of abdominal wall hernias in fertile women before or during pregnancy. METHODS: A literature search was undertaken in Pub......Med and Embase in combination with a cross-reference search of eligible papers. RESULTS: We included 31 papers of which 23 were case reports. In fertile women undergoing sutured or mesh repair, pain was described in a few patients during the last trimester of a subsequent pregnancy. Emergency surgery...... of incarcerated hernias in pregnant women, as well as combined hernia repair and cesarean section appears as safe procedures. No major complications were reported following hernia repair before or during pregnancy. The combined procedure of elective cesarean section and abdominal wall hernia repair was reported...

  2. Abdominal actinomycosis mimicking acute appendicitis.

    Science.gov (United States)

    Conrad, Robert Joseph; Riela, Steven; Patel, Ravi; Misra, Subhasis

    2015-01-01

    A 52-year-old Hispanic woman presented to the emergency department, reporting worsening sharp lower right quadrant abdominal pain for 3 days. CT of the abdomen and pelvis showed evidence of inflammation in the peritoneal soft tissues adjacent to an enlarged and thick-walled appendix, an appendicolith, no abscess formation and a slightly thickened caecum consistent with acute appendicitis. During laparoscopic appendectomy, the caecum was noted to be firm, raising suspicion of malignancy. Surgical oncology team was consulted and open laparotomy with right hemicolectomy was performed. Pathology reported that the ileocaecal mass was not a malignancy but was, rather, actinomycosis. The patient was discharged after 10 days of intravenous antibiotics in the hospital, with the diagnosis of abdominal actinomycosis. Although the original clinical and radiological findings in this case were highly suggestive of acute appendicitis, abdominal actinomycosis should be in the differential for right lower quadrant pain as it may be treated non-operatively.

  3. Heritability and Genetic Relationship of Adult Self-Reported Stuttering, Cluttering and Childhood Speech-Language Disorders

    DEFF Research Database (Denmark)

    Fagnani, Corrado; Fibiger, Steen; Skytthe, Axel

    2011-01-01

    Genetic influence and mutual genetic relationship for adult self-reported childhood speech-language disorders, stuttering, and cluttering were studied. Using nationwide questionnaire answers from 34,944 adult Danish twins, a multivariate biometric analysis based on the liability-threshold model...... for monozygotic compared to dizygotic pairs, suggesting genetic influence. Multivariate biometric analyses showed that additive genetic and unique environmental factors best explained the observed concordance patterns. Heritability estimates for males/females were 0.71/0.87 for childhood speech-language disorders......, 0.78/0.80 for stuttering, and 0.53/0.65 for cluttering. For each trait, the same genes were suggested to affect liability in males and females. Furthermore, high genetic correlations between the traits were obtained; the estimates for childhood speech-language disorders and stuttering were 0...

  4. Design of a Demonstrator of an Adaptive steerable Antenna system for removal of Interference, clutter, Jammer based on AWG &VSA

    Directory of Open Access Journals (Sweden)

    M Chakraborty

    2012-10-01

    Full Text Available Interfering, clutter and jamming systems are becoming an increasing concern to the military and security industries worldwide. To overcome these problems phase array antennas and adaptive beam forming systems offers a potential solution. STAP is an application of optimum and adaptive array processing algorithms to the radar problem of target detection in ground clutter and interference with pulse-Doppler waveforms.In this paper we have presented our work of designing a MVDR beam former receiver using AWG and VSA. The minimumvariance distortion less response (MVDR approach is very popular technic in array processing that generates some mean square error or values. When these values fed to the phase array antenna system results in electronic steering of antenna beam according to the weight vector generated.

  5. CT appearances of abdominal tuberculosis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, W.-K., E-mail: leewk33@hotmail.com [Department of Medical Imaging, St Vincent' s Hospital, University of Melbourne, Fitzroy, Victoria (Australia); Van Tonder, F.; Tartaglia, C.J.; Dagia, C. [Department of Medical Imaging, St Vincent' s Hospital, University of Melbourne, Fitzroy, Victoria (Australia); Cazzato, R.L. [Department of Radiology, Universita Campus Bio-Medico di Roma, Rome (Italy); Duddalwar, V.A. [Department of Radiology, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, California (United States); Chang, S.D. [Department of Medical Imaging, Vancouver General Hospital, University of British Columbia, British Columbia (Canada)

    2012-06-15

    The purpose of this article is to review and illustrate the spectrum of computed tomography (CT) appearances of abdominal tuberculosis. Tuberculosis can affect any organ or tissue in the abdomen, and can be mistaken for other inflammatory or neoplastic conditions. The most common sites of tuberculosis in the abdomen include lymph nodes, genitourinary tract, peritoneal cavity and gastrointestinal tract. The liver, spleen, biliary tract, pancreas and adrenals are rarely affected, but are more likely in HIV-seropositive patients and in miliary tuberculosis. This article should alert the radiologist to consider abdominal tuberculosis in the correct clinical setting to ensure timely diagnosis and enable appropriate treatment.

  6. Blunt abdominal trauma in sports.

    Science.gov (United States)

    Rifat, Sami F; Gilvydis, Rimas P

    2003-04-01

    Abdominal injuries are rare in sports, but when they do occur it is important that the physician recognize the warning signs of potentially life-threatening injury to the liver, spleen, or hollow abdominal viscera. Though the sports medicine physician may not always provide definitive treatment of many of these conditions, he or she should be familiar with the preferred diagnostic modalities and latest treatment options. This information is not only essential to appropriately participate in treatment decisions, but is also important in order to make return-to-play determinations.

  7. [Gallstone ileus. Abdominal CT usefulness].

    Science.gov (United States)

    Sukkarieh, F; Brasseur, P; Bissen, L

    2004-06-01

    The authors report the case of a 93-year old woman referred to the emergency department and presenting with an intestinal obstruction. Abdominal CT reveals a biliary ileus caused by the migration and the impaction of a 3 cm gallstone in the small bowel. Surgical treatment by enterolithotomy was successful. In over 90% of cases, gallstone ileus is a complication of cholelithiasis and accounts for 25% of intestinal obstruction in patients over 65 years. To reduce morbidity and mortality, early diagnosis and prompt treatment are essential. Abdominal CT-scan is the gold standard technique.

  8. Diagnosis in acute abdominal pain and ongoing abdominal sepsis

    NARCIS (Netherlands)

    Kiewiet, J.J.S.

    2016-01-01

    Acute abdominal pain is a common reason for presentation at the emergency department. To establish a timely and adequate diagnosis, doctors use the pattern of complaints and physical examination as the basis for the evaluation of a patient. In this thesis we conducted a study that showed that surgeo

  9. Expertise Effects in Face-Selective Areas are Robust to Clutter and Diverted Attention, but not to Competition.

    Science.gov (United States)

    McGugin, Rankin Williams; Van Gulick, Ana E; Tamber-Rosenau, Benjamin J; Ross, David A; Gauthier, Isabel

    2015-09-01

    Expertise effects for nonface objects in face-selective brain areas may reflect stable aspects of neuronal selectivity that determine how observers perceive objects. However, bottom-up (e.g., clutter from irrelevant objects) and top-down manipulations (e.g., attentional selection) can influence activity, affecting the link between category selectivity and individual performance. We test the prediction that individual differences expressed as neural expertise effects for cars in face-selective areas are sufficiently stable to survive clutter and manipulations of attention. Additionally, behavioral work and work using event related potentials suggest that expertise effects may not survive competition; we investigate this using functional magnetic resonance imaging. Subjects varying in expertise with cars made 1-back decisions about cars, faces, and objects in displays containing one or 2 objects, with only one category attended. Univariate analyses suggest car expertise effects are robust to clutter, dampened by reducing attention to cars, but nonetheless more robust to manipulations of attention than competition. While univariate expertise effects are severely abolished by competition between cars and faces, multivariate analyses reveal new information related to car expertise. These results demonstrate that signals in face-selective areas predict expertise effects for nonface objects in a variety of conditions, although individual differences may be expressed in different dependent measures depending on task and instructions.

  10. Techniques for Clutter Suppression in the Presence of Body Movements during the Detection of Respiratory Activity through UWB Radars

    Directory of Open Access Journals (Sweden)

    Antonio Lazaro

    2014-02-01

    Full Text Available This paper focuses on the feasibility of tracking the chest wall movement of a human subject during respiration from the waveforms recorded using an impulse-radio (IR ultra-wideband radar. The paper describes the signal processing to estimate sleep apnea detection and breathing rate. Some techniques to solve several problems in these types of measurements, such as the clutter suppression, body movement and body orientation detection are described. Clutter suppression is achieved using a moving averaging filter to dynamically estimate it. The artifacts caused by body movements are removed using a threshold method before analyzing the breathing signal. The motion is detected using the time delay that maximizes the received signal after a clutter removing algorithm is applied. The periods in which the standard deviations of the time delay exceed a threshold are considered macro-movements and they are neglected. The sleep apnea intervals are detected when the breathing signal is below a threshold. The breathing rate is determined from the robust spectrum estimation based on Lomb periodogram algorithm. On the other hand the breathing signal amplitude depends on the body orientation respect to the antennas, and this could be a problem. In this case, in order to maximize the signal-to-noise ratio, multiple sensors are proposed to ensure that the backscattered signal can be detected by at least one sensor, regardless of the direction the human subject is facing. The feasibility of the system is compared with signals recorded by a microphone.

  11. Dynamic EMI sensor platform for digital geophysical mapping and automated clutter rejection for CONUS and OCONUS applications

    Science.gov (United States)

    Laudato, Stephen J.; Schultz, Gregory; Keranen, Joe; Miller, Jonathan S.

    2016-05-01

    The implementation of new advanced electromagnetic induction (EMI) sensor surveys at sites containing unexploded ordnance (UXO) and explosive remnants of war (ERW) is an effective method for accurate mapping and for discriminating clutter from targets of interest. We present development and integration of a next generation advanced EMI sensor onto a cart-based sensing platform to combine the mapping capability of previous digital geophysical survey instruments with the high-resolution discrimination capability of advanced characterization arrays. The EMI sensor employs a multi-axis receiver configuration to produce data sufficient for anomaly discrimination. We discuss platform design and development, data acquisition and post-processing software development, and results from field tests demonstrating the detection and discrimination capability of the cart-based system. Platform development and design focused on navigation and EMI sensor integration onto a custom, low-noise, metal-free platform. Data acquisition is via an Android application with emphasis on ease-of-use and real-time quality control (QC) of collected data. Post-processing methods emphasize QC, inversion-based anomaly location estimation, and automated or supervised polarizability-based discrimination methods to produce a prioritized dig list. Integration of the detection, clutter rejection and QC methods into the post-processing software module reduces the time required between sensor data collection and generation of a prioritized dig list. System concept of operations (CONOPs), data collection, QC, data processing procedures, and performance against various clutter objects and targets of interest will also be discussed.

  12. The application of the multifractal cross-correlation analysis methods in radar target detection within sea clutter

    Science.gov (United States)

    Xi, Caiping; Zhang, Shuning; Xiong, Gang; Zhao, Huichang; Yang, Yonghong

    2017-02-01

    Many complex systems generate multifractal time series which are long-range cross-correlated. This paper introduces three multifractal cross-correlation analysis methods, such as multifractal cross-correlation analysis based on the partition function approach (MFXPF), multifractal detrended cross-correlation analysis (MFDCCA) methods based on detrended fluctuation analysis (MFXDFA) and detrended moving average analysis (MFXDMA), which only consider one moment order. We do comparative analysis of the artificial time series (binomial multiplicative cascades and Cantor sets with different probabilities) by these methods. Then we do a feasibility test of the fixed threshold target detection within sea clutter by applying the multifractal cross-correlation analysis methods to the IPIX radar sea clutter data. The results show that it is feasible to use the method of the fixed threshold based on the multifractal feature parameter Δf(α) by the MFXPF and MFXDFA-1 methods. At last, we give the main conclusions and provide a valuable reference on how to choose the multifractal algorithms, the detection parameters and the target detection methods within sea clutter in practice.

  13. Significance of bacterial flora in abdominal irradiation-induced inhibition of lung metastases

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, T.; Ando, K.; Koike, S.

    1988-06-01

    We have previously reported that abdominal irradiation prior to i.v. injection of syngeneic tumor cells reduced metastases in lung. Our report described an investigation of the significance of intestinal organisms in the radiation effect. We found that eliminating intestinal organisms with antibiotics totally abolished the radiation effect. Monoassociation of germ-free mice revealed that the radiation effect was observable only for Enterobacter cloacae, never for Streptococcus faecium, Bifidobacterium adlesentis, or Escherichia coli. After abdominal irradiation of regular mice, E. cloacae multiplied in cecal contents, adhered to mucous membranes, invaded the cecal wall, and translocated to mesenteric lymph nodes. Intravenous administration of E. cloacae in place of abdominal irradiation inhibited metastases. E. cloacae-monoassociated mice developed fewer metastases than germ-free mice, and the reduction was further enhanced by abdominal irradiation. We concluded that abdominal irradiation caused the invasion of E. cloacae from the mucous membrane of the intestine and inhibited formation of lung metastases.

  14. Abdominal Complications of Typhoid Fever

    OpenAIRE

    Ketan Vagholkar; Jimmy Mirani; Urvashi Jain; Madhavan Iyengar; Rahul Kumar Chavan

    2015-01-01

    The natural history of typhoid fever poses both a diagnostic and a therapeutic challenge. Awareness of the clinical features of the primary presentation and of the complications are pivotal to early diagnosis. Typically, aggressive supportive care is all that is needed. However abdominal complications do occur and proper surgical care is required to lower morbidity and mortality.

  15. Chronic Abdominal Pain in Children

    NARCIS (Netherlands)

    C.F.M. Gijsbers (Carolien)

    2012-01-01

    textabstractRecurrent abdominal pain (RAP) was first defined in 1958 by Apley as “at least 3 bouts of pain, severe enough to affect activities, over a period of at least 3 months” (1). This was a landmark publication with great impact, showing, that emotional disturbances played a role in many patie

  16. Clinical management of abdominal trauma

    Institute of Scientific and Technical Information of China (English)

    FANG Guo-en; LUO Tian-hang; DU Cheng-hui; BI Jian-wei; XUE Xu-chao; WEI Guo; WENG Zhao-zhang; MA Li-ye; HUA Ji-de

    2008-01-01

    Objective: To improve the prognosis of patients with abdominal trauma. Methods: Between January 1993 and December 2005, 415 patients were enrolled in this research. The patients consisted of 347 males and 68 females with mean age of 36 years ranging from 3-82 years. All abdominal traumas consisted of closed traumas 360 cases, 86.7% and open traumas 55 cases, 13.3%. Results: Atotal of 407 cases 98.1% were fully recovered from trauma and the other 8 cases 1.9% died of multiple injuries. The mean injury severity score ISS of all patients was 22 while the mean ISS of the patients who died in hospital was 42. Postoperative complications were seen in 9 patients such as infection of incisional wounds 6 cases, pancreatic fistula 2 cases and intestinal fistula 1 case. All these postoperative complications were cured by the conservative treatment. Conclusion: Careful case history inquisition and physical examination are the basic methods to diagnose abdomi- nal trauma. Focused abdominal ultrasonography is always the initial imaging examination because it is non-invasive and can be performed repeatedly with high accuracy. The doctors should consider the severity of local injuries and the general status of patients during the assessment of abdominal trauma. The principle of treatment is to save lives at first, then to cure the injuries. Unnecessary laparotomy should be avoided to reduce additional surgical trauma.

  17. Mixture-Tuned, Clutter Matched Filter for Remote Detection of Subpixel Spectral Signals

    Science.gov (United States)

    Thompson, David R.; Mandrake, Lukas; Green, Robert O.

    2013-01-01

    Mapping localized spectral features in large images demands sensitive and robust detection algorithms. Two aspects of large images that can harm matched-filter detection performance are addressed simultaneously. First, multimodal backgrounds may thwart the typical Gaussian model. Second, outlier features can trigger false detections from large projections onto the target vector. Two state-of-the-art approaches are combined that independently address outlier false positives and multimodal backgrounds. The background clustering models multimodal backgrounds, and the mixture tuned matched filter (MT-MF) addresses outliers. Combining the two methods captures significant additional performance benefits. The resulting mixture tuned clutter matched filter (MT-CMF) shows effective performance on simulated and airborne datasets. The classical MNF transform was applied, followed by k-means clustering. Then, each cluster s mean, covariance, and the corresponding eigenvalues were estimated. This yields a cluster-specific matched filter estimate as well as a cluster- specific feasibility score to flag outlier false positives. The technology described is a proof of concept that may be employed in future target detection and mapping applications for remote imaging spectrometers. It is of most direct relevance to JPL proposals for airborne and orbital hyperspectral instruments. Applications include subpixel target detection in hyperspectral scenes for military surveillance. Earth science applications include mineralogical mapping, species discrimination for ecosystem health monitoring, and land use classification.

  18. A Low-Complexity Algorithm for Static Background Estimation from Cluttered Image Sequences in Surveillance Contexts

    Directory of Open Access Journals (Sweden)

    Reddy Vikas

    2011-01-01

    Full Text Available Abstract For the purposes of foreground estimation, the true background model is unavailable in many practical circumstances and needs to be estimated from cluttered image sequences. We propose a sequential technique for static background estimation in such conditions, with low computational and memory requirements. Image sequences are analysed on a block-by-block basis. For each block location a representative set is maintained which contains distinct blocks obtained along its temporal line. The background estimation is carried out in a Markov Random Field framework, where the optimal labelling solution is computed using iterated conditional modes. The clique potentials are computed based on the combined frequency response of the candidate block and its neighbourhood. It is assumed that the most appropriate block results in the smoothest response, indirectly enforcing the spatial continuity of structures within a scene. Experiments on real-life surveillance videos demonstrate that the proposed method obtains considerably better background estimates (both qualitatively and quantitatively than median filtering and the recently proposed "intervals of stable intensity" method. Further experiments on the Wallflower dataset suggest that the combination of the proposed method with a foreground segmentation algorithm results in improved foreground segmentation.

  19. Audio-visual speech timing sensitivity is enhanced in cluttered conditions.

    Directory of Open Access Journals (Sweden)

    Warrick Roseboom

    Full Text Available Events encoded in separate sensory modalities, such as audition and vision, can seem to be synchronous across a relatively broad range of physical timing differences. This may suggest that the precision of audio-visual timing judgments is inherently poor. Here we show that this is not necessarily true. We contrast timing sensitivity for isolated streams of audio and visual speech, and for streams of audio and visual speech accompanied by additional, temporally offset, visual speech streams. We find that the precision with which synchronous streams of audio and visual speech are identified is enhanced by the presence of additional streams of asynchronous visual speech. Our data suggest that timing perception is shaped by selective grouping processes, which can result in enhanced precision in temporally cluttered environments. The imprecision suggested by previous studies might therefore be a consequence of examining isolated pairs of audio and visual events. We argue that when an isolated pair of cross-modal events is presented, they tend to group perceptually and to seem synchronous as a consequence. We have revealed greater precision by providing multiple visual signals, possibly allowing a single auditory speech stream to group selectively with the most synchronous visual candidate. The grouping processes we have identified might be important in daily life, such as when we attempt to follow a conversation in a crowded room.

  20. A patterned and un-patterned minefield detection in cluttered environments using Markov marked point process

    Science.gov (United States)

    Trang, Anh; Agarwal, Sanjeev; Regalia, Phillip; Broach, Thomas; Smith, Thomas

    2007-04-01

    A typical minefield detection approach is based on a sequential processing employing mine detection and false alarm rejection followed by minefield detection. The current approach does not work robustly under different backgrounds and environment conditions because target signature changes with time and its performance degrades in the presence of high density of false alarms. The aim of this research will be to advance the state of the art in detection of both patterned and unpatterned minefield in high clutter environments. The proposed method seeks to combine false alarm rejection module and the minefield detection module of the current architecture by spatial-spectral clustering and inference module using a Markov Marked Point Process formulation. The approach simultaneously exploits the feature characteristics of the target signature and spatial distribution of the targets in the interrogation region. The method is based on the premise that most minefields can be characterized by some type of distinctive spatial distribution of "similar" looking mine targets. The minefield detection problem is formulated as a Markov Marked Point Process (MMPP) where the set of possible mine targets is divided into a possibly overlapping mixture of targets. The likelihood of the minefield depends simultaneously on feature characteristics of the target and their spatial distribution. A framework using "Belief Propagation" is developed to solve the minefield inference problem based on MMPP. Preliminary investigation using simulated data shows the efficacy of the approach.

  1. Rule-Driven Object Tracking in Clutter and Partial Occlusion with Model-Based Snakes

    Directory of Open Access Journals (Sweden)

    Rapantzikos Konstantinos

    2004-01-01

    Full Text Available In the last few years it has been made clear to the research community that further improvements in classic approaches for solving low-level computer vision and image/video understanding tasks are difficult to obtain. New approaches started evolving, employing knowledge-based processing, though transforming a priori knowledge to low-level models and rules are far from being straightforward. In this paper, we examine one of the most popular active contour models, snakes, and propose a snake model, modifying terms and introducing a model-based one that eliminates basic problems through the usage of prior shape knowledge in the model. A probabilistic rule-driven utilization of the proposed model follows, being able to handle (or cope with objects of different shapes, contour complexities and motions; different environments, indoor and outdoor; cluttered sequences; and cases where background is complex (not smooth and when moving objects get partially occluded. The proposed method has been tested in a variety of sequences and the experimental results verify its efficiency.

  2. Great expectations: top-down attention modulates the costs of clutter and eccentricity.

    Science.gov (United States)

    Steelman, Kelly S; McCarley, Jason S; Wickens, Christopher D

    2013-12-01

    An experiment and modeling effort examined interactions between bottom-up and top-down attentional control in visual alert detection. Participants performed a manual tracking task while monitoring peripheral display channels for alerts of varying salience, eccentricity, and spatial expectancy. Spatial expectancy modulated the influence of salience and eccentricity; alerts in low-probability locations engendered higher miss rates, longer detection times, and larger costs of visual clutter and eccentricity, indicating that top-down attentional control offset the costs of poor bottom-up stimulus quality. Data were compared to the predictions of a computational model of scanning and noticing that incorporates bottom-up and top-down sources of attentional control. The model accounted well for the overall pattern of miss rates and response times, predicting each of the observed main effects and interactions. Empirical results suggest that designers should expect the costs of poor bottom-up visibility to be greater for low expectancy signals, and that the placement of alerts within a display should be determined based on the combination of alert expectancy and response priority. Model fits suggest that the current model can serve as a useful tool for exploring a design space as a precursor to empirical data collection and for generating hypotheses for future experiments.

  3. Object Extraction in Cluttered Environments via a P300-Based IFCE

    Directory of Open Access Journals (Sweden)

    Xiaoqian Mao

    2017-01-01

    Full Text Available One of the fundamental issues for robot navigation is to extract an object of interest from an image. The biggest challenges for extracting objects of interest are how to use a machine to model the objects in which a human is interested and extract them quickly and reliably under varying illumination conditions. This article develops a novel method for segmenting an object of interest in a cluttered environment by combining a P300-based brain computer interface (BCI and an improved fuzzy color extractor (IFCE. The induced P300 potential identifies the corresponding region of interest and obtains the target of interest for the IFCE. The classification results not only represent the human mind but also deliver the associated seed pixel and fuzzy parameters to extract the specific objects in which the human is interested. Then, the IFCE is used to extract the corresponding objects. The results show that the IFCE delivers better performance than the BP network or the traditional FCE. The use of a P300-based IFCE provides a reliable solution for assisting a computer in identifying an object of interest within images taken under varying illumination intensities.

  4. Stochastic transfer of polarized radiation in finite cluttered atmospheric media with dual statistical analysis

    Science.gov (United States)

    Sallah, M.

    2015-09-01

    The stochastic transfer of polarized radiation in a finite cluttered atmospheric medium (e.g. clouds) is investigated, the solution being presented for arbitrary absorption and scattering cross sections. The extinction function of the medium is assumed to be a continuous random function of position, with fluctuations about the mean taken as Gaussian distributed. The deterministic analytical solution is obtained by using Pomraning-Eddington technique with weight function method. Two correlated random variables appear in the solution, namely the optical space variable and the medium optical thickness. The dual Gaussian probability density function of these two random variables is derived, from which the ensemble-averaged solution is calculated for an arbitrary correlation function. The first and the second statistical moments of some quantities of interest, such as radiant energy, net flux, reflectivity and transmissivity, are obtained. Numerical calculations are performed for specular-reflecting boundaries and an incident flux of radiation upon the medium from one side (x = 0) and with no flux from other side (x = L) .

  5. Validating determinants for an alternate foot placement selection algorithm during human locomotion in cluttered terrain.

    Science.gov (United States)

    Moraes, Renato; Allard, Fran; Patla, Aftab E

    2007-10-01

    The goal of this study was to validate dynamic stability and forward progression determinants for the alternate foot placement selection algorithm. Participants were asked to walk on level ground and avoid stepping, when present, on a virtual white planar obstacle. They had a one-step duration to select an alternate foot placement, with the task performed under two conditions: free (participants chose the alternate foot placement that was appropriate) and forced (a green arrow projected over the white planar obstacle cued the alternate foot placement). To validate the dynamic stability determinant, the distance between the extrapolated center of mass (COM) position, which incorporates the dynamics of the body, and the limits of the base of support was calculated in both anteroposterior (AP) and mediolateral (ML) directions in the double support phase. To address the second determinant, COM deviation from straight ahead was measured between adaptive and subsequent steps. The results of this study showed that long and lateral choices were dominant in the free condition, and these adjustments did not compromise stability in both adaptive and subsequent steps compared with the short and medial adjustments, which were infrequent and adversely affected stability. Therefore stability is critical when selecting an alternate foot placement in a cluttered terrain. In addition, changes in the plane of progression resulted in small deviations of COM from the endpoint goal. Forward progression of COM was maintained even for foot placement changes in the frontal plane, validating this determinant as part of the selection algorithm.

  6. Reinforcement Learning with Autonomous Small Unmanned Aerial Vehicles in Cluttered Environments

    Science.gov (United States)

    Tran, Loc; Cross, Charles; Montague, Gilbert; Motter, Mark; Neilan, James; Qualls, Garry; Rothhaar, Paul; Trujillo, Anna; Allen, B. Danette

    2015-01-01

    We present ongoing work in the Autonomy Incubator at NASA Langley Research Center (LaRC) exploring the efficacy of a data set aggregation approach to reinforcement learning for small unmanned aerial vehicle (sUAV) flight in dense and cluttered environments with reactive obstacle avoidance. The goal is to learn an autonomous flight model using training experiences from a human piloting a sUAV around static obstacles. The training approach uses video data from a forward-facing camera that records the human pilot's flight. Various computer vision based features are extracted from the video relating to edge and gradient information. The recorded human-controlled inputs are used to train an autonomous control model that correlates the extracted feature vector to a yaw command. As part of the reinforcement learning approach, the autonomous control model is iteratively updated with feedback from a human agent who corrects undesired model output. This data driven approach to autonomous obstacle avoidance is explored for simulated forest environments furthering autonomous flight under the tree canopy research. This enables flight in previously inaccessible environments which are of interest to NASA researchers in Earth and Atmospheric sciences.

  7. Bistatic, above-critical angle scattering measurements of fully buried unexploded ordnance (UXO) and clutter.

    Science.gov (United States)

    Waters, Z J; Simpson, H J; Sarkissian, A; Dey, S; Houston, B H; Bucaro, J A; Yoder, T J

    2012-11-01

    Laboratory grade bistatic scattering measurements are conducted in order to examine the acoustic response of realistic fully buried unexploded ordnance (UXO) from above-critical angle insonification, between 2 and 40 kHz. A 127 mm diameter rocket UXO, a 155 mm diameter artillery shell, a natural rock of approximately the same size, and a cinder block are fully buried in water-saturated medium grained sand (mean grain diameter, 240 μm) at depths of 10 cm below the water-sediment interface. A two-dimensional array of bistatic scattering measurements is generated synthetically by scanning a single hydrophone in steps of 3 cm over a 1 m × 1 m patch directly above the targets at a height of 20 cm above the water-sediment interface. Three-dimensional volumetric acoustic images generated from the return waveforms reveal scattering components attributed to geometric and elastic scattering, as well as multiple-scattering interactions of returns between the sediment-water interface and the buried objects. The far-field target strength of the objects is estimated through extrapolation of the angular spectrum. Agreement is found between experimental data and simulated data generated from a finite-element-based, three-dimensional time-harmonic model (2-25 kHz). Separation of the measured UXO from the clutter objects is demonstrated through exploitation of structural-acoustics-based features.

  8. Preoperative steroid in abdominal wall reconstruction

    DEFF Research Database (Denmark)

    Jensen, Kristian Kiim; Brøndum, Tina Lee; Belhage, Bo

    2016-01-01

    INTRODUCTION: Preoperative administration of high-dose glucocorticoid leads to improved recovery and decreased length of stay after abdominal surgery. Even so, studies on administration of glucocorticoids for patients undergoing abdominal wall reconstruction (AWR) for giant ventral hernia repair ...

  9. Emergency abdominal surgery in Zaria, Nigeria

    African Journals Online (AJOL)

    Abdominal surgical emergencies constitute a significant portion of a surgeon's ... causes of abdominal emergencies vary from region to region, and even within the ..... Previous studies from our sub-region have consistently shown strangulated ...

  10. Preoperative steroid in abdominal wall reconstruction

    DEFF Research Database (Denmark)

    Jensen, Kristian Kiim; Brøndum, Tina Lee; Belhage, Bo;

    2016-01-01

    INTRODUCTION: Preoperative administration of high-dose glucocorticoid leads to improved recovery and decreased length of stay after abdominal surgery. Even so, studies on administration of glucocorticoids for patients undergoing abdominal wall reconstruction (AWR) for giant ventral hernia repair ...

  11. Abdominal aortic aneurysm repair - open - discharge

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000240.htm Abdominal aortic aneurysm repair - open - discharge To use the sharing features ... References Orandi BJ, Black JH. Open repair of abdominal aortic aneurysms. In: Cameron JL, Cameron AM, eds. Current Surgical ...

  12. Abdominal Compartment Syndrome: pathophysiology and definitions

    OpenAIRE

    Cheatham Michael L

    2009-01-01

    Abstract "Intra-abdominal hypertension", the presence of elevated intra-abdominal pressure, and "abdominal compartment syndrome", the development of pressure-induced organ-dysfunction and failure, have been increasingly recognized over the past decade as causes of significant morbidity and mortality among critically ill surgical and medical patients. Elevated intra-abdominal pressure can cause significant impairment of cardiac, pulmonary, renal, gastrointestinal, hepatic, and central nervous ...

  13. Superman play and pediatric blunt abdominal trauma.

    Science.gov (United States)

    Machi, J M; Gyuro, J; Losek, J D

    1996-01-01

    Two pediatric patients with life-threatening intra-abdominal injuries associated with Superman play are presented. The cases illustrate the importance of knowing the mechanism of injury in the assessment of children with blunt abdominal trauma. The diagnostic value of liver enzymes and the controversies surrounding the radiographic assessment of pediatric blunt abdominal trauma are presented.

  14. Abdominal migraine in childhood: a review

    OpenAIRE

    Scicchitano B; Humphreys G; Mitton SG; Jaiganesh T

    2014-01-01

    Beatrice Scicchitano,1 Gareth Humphreys,1 Sally G Mitton,2 Thiagarajan Jaiganesh1 1Children's Emergency Department, 2Department of Paediatric Gastroenterology, St Georges Hospital, St Georges Healthcare NHS Trust, Tooting, London, United Kingdom Abstract: The childhood condition of abdominal migraine has been described under many different synonyms, including "abdominal epilepsy", "recurrent abdominal pain", "cyclical vomiting syndrome&...

  15. Intra-Abdominal Actinomycosis Mimicking Malignant Abdominal Disease

    Directory of Open Access Journals (Sweden)

    Ali Ridha

    2017-01-01

    Full Text Available Abdominal actinomycosis is a rare infectious disease, caused by gram positive anaerobic bacteria, that may appear as an abdominal mass and/or abscess (Wagenlehner et al. 2003. This paper presents an unusual case of a hemodynamically stable 80-year-old man who presented to the emergency department with 4 weeks of worsening abdominal pain and swelling. He also complains of a 20-bound weight loss in 2 months. A large tender palpable mass in the right upper quadrant was noted on physical exam. Laboratory studies showed a normal white blood cell count, slightly decreased hemoglobin and hematocrit, and mildly elevated total bilirubin and alkaline phosphatase. A CT with contrast was done and showed a liver mass. Radiology and general surgery suspected malignancy and recommended CT guided biopsy. The sample revealed abundant neutrophils and gram positive rods. Cytology was negative for malignancy and cultures eventually grew actinomyces. High dose IV penicillin therapy was given for 4 weeks and with appropriate response transitioned to oral antibiotic for 9 months with complete resolution of symptoms.

  16. Intra-Abdominal Actinomycosis Mimicking Malignant Abdominal Disease

    Science.gov (United States)

    Oguejiofor, Njideka; Al-Abayechi, Sarah; Njoku, Emmanuel

    2017-01-01

    Abdominal actinomycosis is a rare infectious disease, caused by gram positive anaerobic bacteria, that may appear as an abdominal mass and/or abscess (Wagenlehner et al. 2003). This paper presents an unusual case of a hemodynamically stable 80-year-old man who presented to the emergency department with 4 weeks of worsening abdominal pain and swelling. He also complains of a 20-bound weight loss in 2 months. A large tender palpable mass in the right upper quadrant was noted on physical exam. Laboratory studies showed a normal white blood cell count, slightly decreased hemoglobin and hematocrit, and mildly elevated total bilirubin and alkaline phosphatase. A CT with contrast was done and showed a liver mass. Radiology and general surgery suspected malignancy and recommended CT guided biopsy. The sample revealed abundant neutrophils and gram positive rods. Cytology was negative for malignancy and cultures eventually grew actinomyces. High dose IV penicillin therapy was given for 4 weeks and with appropriate response transitioned to oral antibiotic for 9 months with complete resolution of symptoms. PMID:28299215

  17. The Diagnostic Value of Intra-abdominal Pressure in Patients with Blunt Acute Abdominal Trauma

    Directory of Open Access Journals (Sweden)

    Huseyin Narci

    2012-06-01

    Full Text Available Purpose:The objective of this study was to determine the diagnostic value of intra-abdominal pressure measurement in blunt abdominal trauma patients. Method: A prospective study was performed in 49 patients with blunt trauma in our university hospital for 1 years. Patients were randomly into two groups as intra-abdominal trauma (n=28 and extraabdominal trauma (n=21 groups. Intra-abdominal pressures was measured an classified as normal (10 cm H2O or less, elevated (more than 10 cm H2O determined indirectly. Results: No significant differences were found between abdominal trauma and extra-abdominal trauma groups from the point of intra-abdominal pressure (IAP. One the other hand, in abdominal trauma group; significant differences were observed between operated patients. Intra-abdominal bleeding was found in 10 patients and all of them elevated IAP values (exceeding 16 cm H2O. For determining the intra-abdominal injury, IAP had a sensitivity of 93%, specificity 38% in patients. Conclusion: IAP exceeding 16 cm H2O with blunt abdominal trauma patients abdominal trauma can be detected. It is thought that IAP, indirect monitoring of abdominal trauma patients is a reproducible, scientific guide and simple method.To determine the efficacy of the measurement of intra-abdominal pressure in blunt abdominal trauma patients, further studies should be done. [Cukurova Med J 2012; 37(3.000: 157-161

  18. Acupuncture Treatment of Abdominal Pain

    Institute of Scientific and Technical Information of China (English)

    胡金生

    2002-01-01

    @@ Case History Mr. Li, a university student aged 23 years, paid his first visit on July 16, 2001, with the chief complaint of abdominal pain for one day. The patient stated that one day before when it happened to be the weekend, he got abdominal pain after supper, which went worse gradually and caused him to roll all over in bed. The pain was slightly alleviated half an hour later after he had taken some pain killers. Upon inquiry, the patient said that because of their newly graduation from the university, he and his classmates were so excited that they went to have a sumptuous lunch with alcoholic drinks. And in the evening he ate again a delicious supper cooked for him by his mother, after which he continued to have some fruit and dessert.

  19. Enabling UAV Navigation with Sensor and Environmental Uncertainty in Cluttered and GPS-Denied Environments.

    Science.gov (United States)

    Vanegas, Fernando; Gonzalez, Felipe

    2016-05-10

    Unmanned Aerial Vehicles (UAV) can navigate with low risk in obstacle-free environments using ground control stations that plan a series of GPS waypoints as a path to follow. This GPS waypoint navigation does however become dangerous in environments where the GPS signal is faulty or is only present in some places and when the airspace is filled with obstacles. UAV navigation then becomes challenging because the UAV uses other sensors, which in turn generate uncertainty about its localisation and motion systems, especially if the UAV is a low cost platform. Additional uncertainty affects the mission when the UAV goal location is only partially known and can only be discovered by exploring and detecting a target. This navigation problem is established in this research as a Partially-Observable Markov Decision Process (POMDP), so as to produce a policy that maps a set of motion commands to belief states and observations. The policy is calculated and updated on-line while flying with a newly-developed system for UAV Uncertainty-Based Navigation (UBNAV), to navigate in cluttered and GPS-denied environments using observations and executing motion commands instead of waypoints. Experimental results in both simulation and real flight tests show that the UAV finds a path on-line to a region where it can explore and detect a target without colliding with obstacles. UBNAV provides a new method and an enabling technology for scientists to implement and test UAV navigation missions with uncertainty where targets must be detected using on-line POMDP in real flight scenarios.

  20. Enabling UAV Navigation with Sensor and Environmental Uncertainty in Cluttered and GPS-Denied Environments

    Directory of Open Access Journals (Sweden)

    Fernando Vanegas

    2016-05-01

    Full Text Available Unmanned Aerial Vehicles (UAV can navigate with low risk in obstacle-free environments using ground control stations that plan a series of GPS waypoints as a path to follow. This GPS waypoint navigation does however become dangerous in environments where the GPS signal is faulty or is only present in some places and when the airspace is filled with obstacles. UAV navigation then becomes challenging because the UAV uses other sensors, which in turn generate uncertainty about its localisation and motion systems, especially if the UAV is a low cost platform. Additional uncertainty affects the mission when the UAV goal location is only partially known and can only be discovered by exploring and detecting a target. This navigation problem is established in this research as a Partially-Observable Markov Decision Process (POMDP, so as to produce a policy that maps a set of motion commands to belief states and observations. The policy is calculated and updated on-line while flying with a newly-developed system for UAV Uncertainty-Based Navigation (UBNAV, to navigate in cluttered and GPS-denied environments using observations and executing motion commands instead of waypoints. Experimental results in both simulation and real flight tests show that the UAV finds a path on-line to a region where it can explore and detect a target without colliding with obstacles. UBNAV provides a new method and an enabling technology for scientists to implement and test UAV navigation missions with uncertainty where targets must be detected using on-line POMDP in real flight scenarios.

  1. Channel probe measurements for the American sector clutter experiment, January, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Fitzgerald, T.J.

    1994-05-20

    The ionospheric phenomenon called Equatorial Spread F encompasses a variety of effects associated with plasma irregularities occurring in the post-sunset and nighttime ionosphere near the magnetic equator. These irregularities can seriously degrade the performance of systems which involve either of necessity or inadvertently radio propagation through the equatorial ionosphere. One such system is Over-the-Horizon (OTH) radars which operate in the high-frequency (hf) band and use ionospheric reflection for forward and backscatter propagation to ranges of thousands of kilometers. When such radars are directed towards the equator, Spread F irregularities can cause scintillation effects which may be aliased into the ranges of interest and have the effect of causing, excess clutter in which targets may be hidden. In January, 1994 Los Alamos participated in a campaign to measure Spread F effects on OTH propagation from the United States looking towards South America in conjunction with local diagnostics in Peru. During the campaign Los Alamos fielded a 1600 km bistatic path between Piura, Peru, and Arequipa, Peru-, the one-hop reflection region for this path was near the magnetic equator, We obtained four types of measurements: an oblique ionogram between Piura and Arequipa every three minutes; Doppler spread and spatial correlation for a single frequency cw path between Piura and Arequipa; Doppler spread, time-delay spread, and spatial coherence for a 10 kHz bandwidth path between Piura and Arequipa-, and Doppler spread and time-delay spread for the one-way path between the AVA radar in New York and Arequipa, Peru. This report describes the diagnostic experiments that we carried out and gives a brief description of some of the data we obtained.

  2. Abdominal wound closure: current perspectives

    Directory of Open Access Journals (Sweden)

    Williams ZF

    2015-12-01

    Full Text Available Zachary F Williams, William W Hope Department of Surgery, South East Area Health Education Center, New Hanover Regional Medical Center, Wilmington, NC, USA Abstract: This review examines both early and late wound complications following laparotomy closure, with particular emphasis on technical aspects that reduce hernia formation. Abdominal fascial closure is an area of considerable variation within the field of general surgery. The formation of hernias following abdominal wall incisions continues to be a challenging problem. Ventral hernia repairs are among the most common surgeries performed by general surgeons, and despite many technical advances in the field, incisional hernia rates remain high. Much attention and research has been directed to the surgical management of hernias. Less focus has been placed on prevention of hernia formation despite its obvious importance. This review examines the effects of factors such as the type of incision, suture type and size, closure method, patient risk factors, and the use of prophylactic mesh. Keywords: incisional, abdominal, hernia, prevention, wound closure techniques 

  3. Appendicitis following blunt abdominal trauma.

    Science.gov (United States)

    Cobb, Travis

    2017-09-01

    Appendicitis is a frequently encountered surgical problem in the Emergency Department (ED). Appendicitis typically results from obstruction of the appendiceal lumen, although trauma has been reported as an infrequent cause of acute appendicitis. Intestinal injury and hollow viscus injury following blunt abdominal trauma are well reported in the literature but traumatic appendicitis is much less common. The pathophysiology is uncertain but likely results from several mechanisms, either in isolation or combination. These include direct compression/crush injury, shearing injury, or from indirect obstruction of the appendiceal lumen by an ileocecal hematoma or traumatic impaction of stool into the appendix. Presentation typically mirrors that of non-traumatic appendicitis with nausea, anorexia, fever, and right lower quadrant abdominal tenderness and/or peritonitis. Evaluation for traumatic appendicitis requires a careful history and physical exam. Imaging with ultrasound or computed tomography is recommended if the history and physical do not reveal an acute surgical indication. Treatment includes intravenous antibiotics and surgical consultation for appendectomy. This case highlights a patient who developed acute appendicitis following blunt trauma to the abdomen sustained during a motor vehicle accident. Appendicitis must be considered as part of the differential diagnosis in any patient who presents to the ED with abdominal pain, including those whose pain begins after sustaining blunt trauma to the abdomen. Because appendicitis following trauma is uncommon, timely diagnosis requires a high index of suspicion. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. The Effect of Abdominal Support on Functional Outcomes in Patients Following Major Abdominal Surgery: A Randomized Controlled Trial

    Science.gov (United States)

    Cheifetz, Oren; Overend, Tom J.; Crowe, Jean

    2010-01-01

    ABSTRACT Purpose: Immobility and pain are modifiable risk factors for development of venous thromboembolism and pulmonary morbidity after major abdominal surgery (MAS). The purpose of this study was to investigate the effect of abdominal incision support with an elasticized abdominal binder on postoperative walk performance (mobility), perceived distress, pain, and pulmonary function in patients following MAS. Methods: Seventy-five patients scheduled to undergo MAS via laparotomy were randomized to experimental (binder) or control (no binder) groups. Sixty (33 male, 27 female; mean age 58±14.9 years) completed the study. Preoperative measurements of 6-minute walk test (6MWT) distance, perceived distress, pain, and pulmonary function were repeated 1, 3, and 5 days after surgery. Results: Surgery was associated with marked postoperative reductions (p<0.001) in walk distance (∼75–78%, day 3) and forced vital capacity (35%, all days) for both groups. Improved 6MWT distance by day 5 was greater (p<0.05) for patients wearing a binder (80%) than for the control group (48%). Pain and symptom-associated distress remained unchanged following surgery with binder usage, increasing significantly (p<0.05) only in the no binder group. Conclusion: Elasticized abdominal binders provide a non-invasive intervention for enhancing recovery of walk performance, controlling pain and distress, and improving patients' experience following MAS. PMID:21629603

  5. Urgent Abdominal Re-Explorations

    Directory of Open Access Journals (Sweden)

    Peskersoy Mustafa

    2006-04-01

    Full Text Available Abstract Background Treatment of a number of complications that occur after abdominal surgeries may require that Urgent Abdominal Re-explorations (UARs, the life-saving and obligatory operations, are performed. The objectives of this study were to evaluate the reasons for performing UARs, outcomes of relaparotomies (RLs and factors that affect mortality. Methods Demographic characteristics; initial diagnoses; information from and complications of the first surgery received; durations and outcomes of UAR(s performed in patients who received early RLs because of complicated abdominal surgeries in our clinic between 01.01.2000 and 31.12.2004 were investigated retrospectively. Statistical analyses were done using the chi-square and Fisher exact tests. Results Early UAR was performed in 81 out of 4410 cases (1.8%. Average patient age was 50.46 (13–81 years with a male-to-female ratio of 60/21. Fifty one (62.96% patients had infection, 41 (50.61% of them had an accompanying serious disease, 24 (29.62% of them had various tumors and 57 (70.37% patients were operated under emergency conditions during first operation. Causes of urgent abdominal re-explorations were as follows: leakage from intestinal repair site or from anostomosis (n:34; 41.97%; hemorrhage (n:15; 18.51%; intestinal perforation (n:8; 9.87%; intraabdominal infection or abscess (n:8; 9.87%; progressive intestinal necrosis (n:7; 8.64%; stomal complications (n:5; 6.17%; and postoperative ileus (n:4; 4.93%. Two or more UARs were performed in 18 (22.22% cases, and overall mortality was 34.97% (n:30. Interval between the first laparotomy and UAR averaged as 6.95 (1–20 days, and average hospitalization period was 27.1 (3–78 days. Mortality rate was found to be higher among the patients who received multiple UARs. The most common (55.5% cause of mortality was sepsis/multiple organ failure (MOF. The rates for common mortality and sepsis/MOF-dependent mortality that occured following UAR were

  6. Abdominal lift for laparoscopic cholecystectomy.

    Science.gov (United States)

    Gurusamy, Kurinchi Selvan; Koti, Rahul; Davidson, Brian R

    2013-08-31

    Laparoscopic cholecystectomy (key-hole removal of the gallbladder) is now the most often used method for treatment of symptomatic gallstones. Several cardiopulmonary changes (decreased cardiac output, pulmonary compliance, and increased peak airway pressure) occur during pneumoperitoneum, which is now introduced to allow laparoscopic cholecystectomy. These cardiopulmonary changes may not be tolerated in individuals with poor cardiopulmonary reserve. To assess the benefits and harms of abdominal wall lift compared to pneumoperitoneum in patients undergoing laparoscopic cholecystectomy. We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and Science Citation Index Expanded until February 2013. We included all randomised clinical trials comparing abdominal wall lift (with or without pneumoperitoneum) versus pneumoperitoneum. We calculated the risk ratio (RR), rate ratio (RaR), or mean difference (MD) with 95% confidence intervals (CI) based on intention-to-treat analysis with both the fixed-effect and the random-effects models using the Review Manager (RevMan) software. For abdominal wall lift with pneumoperitoneum versus pneumoperitoneum, a total of 130 participants (all with low anaesthetic risk) scheduled for elective laparoscopic cholecystectomy were randomised in five trials to abdominal wall lift with pneumoperitoneum (n = 53) versus pneumoperitoneum only (n = 52). One trial which included 25 people did not state the number of participants in each group. All five trials had a high risk of bias. There was no mortality or conversion to open cholecystectomy in any of the participants in the trials that reported these outcomes. There was no significant difference in the rate of serious adverse events between the two groups (two trials; 2/29 events (0.069 events per person) versus 2/29 events (0.069 events per person); rate ratio 1.00; 95% CI 0

  7. Postoperative intussusception in pediatric abdominal malignancies: early diagnosis and management

    Institute of Scientific and Technical Information of China (English)

    Maged M. Elshafiey; Gehad T. Meselhy; Amal Refaat; Alaa A. Younes

    2012-01-01

    Objective: The aim of this study was to review the incidence of postoperative intussusception (POI) in our patients with pediatric abdominal malignancies and the end result of management of these cases. Methods: From November2007 till the end of December 2011, a total of 538 patients with different abdominal malignancies were operated upon by laparotomies in our hospital. Reoperations were required in 12 patients for post operative intestinal obstruction developed in the 1st postoperative month. Review of the identified cases focused on patient's characteristics, the primary tumor type, the primary surgical procedure, clinical and imaging features of the intussusceptions, timing and findings at the 2nd laparotomy and the end result of subsequent interventions. Results: Early post operative intestinal obstruction (within 1 month) developed in 12 patients of whom 8 patients had POI. Five patients had adhesive intestinal obstruction (one patient developed POI then adhesive obstruction). The median duration between the primary surgery and the onset of intestinal obstruction symptoms was 5 days (range 4-12 days) in the POI group and 24 days (range 10-30 days) in the adhesion group. Abdominal CT was done in all cases and it could properly diagnose POI and detect its site in the POI group while in the adhesion group it showed evidence of complete obstruction. Plain radiograph failed to detect signs of intestinal obstruction in 3 cases (two in the POI group and one in the adhesion group). In POI group simple reduction was done in 7 cases while resection anastmosis was done in 1 case due to gangrene of the ileocecal region. Adhesiolysis was done in the 5 cases of intestinal adhesion group.Conclusion: Early POI in pediatric abdominal cancer is a rare complication; however it should be kept in mind with high index of suspicion. Early diagnosis and intervention is essential for successful management. Abdominal CT is very helpful as it can detect the level and possible cause of

  8. Non-traumatic abdominal emergencies: imaging and intervention in sepsis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, M.J. [Department of Radiology, Beaumont Hospital and the Royal College of Surgeons Medical, Beaumont Road, Dublin 9 (Ireland)

    2002-09-01

    Cross-sectional imaging, in particular CT, has become the main method of detecting abdominal collections. Indium-labelled white-cell scintigraphy and gallium scintigraphy are reserved for patients in whom there is a high clinical suspicion of abdominal sepsis but CT has not revealed a source of sepsis. Scintigraphy is also used in patients with suspected vascular graft infections or suspected infected hip prostheses. Percutaneous abscess drainage (PAD) has revolutionised the treatment of abdominal abscesses over the past 20 years, with repeat laparotomy for postoperative abscesses becoming a rare event. Ultrasound or CT can be used to guide PAD. Choosing an access route that does not cross intervening organs is of crucial importance to the safe performance of PAD. The Trocar or Seldinger techniques can be used with equal success. The cavity should be aspirated until dry and irrigated with saline. Repeat imaging after drainage is helpful to detect any undrained locules. PAD endpoints include patient defervescence, reduction in white blood cell count and catheter drainage of less than 10 ml per day. Details regarding PAD in specific abdominal regions are discussed. Success rates for PAD are high (close to 90%) in most abdominal organs. Slightly lower success rates are seen with PAD of pancreatic abscesses and abscesses associated with fistulas (60-85% success rates). Complication rates lie between 0% and 10%. Complications can be minimised by ensuring that the patient has broad spectrum antibiotic coverage before drainage, by carefully planning the access route and by ensuring diligent post-procedure care by radiology staff. (orig.)

  9. Pathogenesis of Intra-abdominal and pelvic adhesion development.

    Science.gov (United States)

    Imudia, Anthony N; Kumar, Sanjeev; Saed, Ghassan M; Diamond, Michael P

    2008-07-01

    Abdominal and pelvic adhesions are a frequent occurrence and are responsible for significant morbidity resulting in abdominal and pelvic pain, infertility, and small bowel obstruction. The process of adhesion development begins when damage to peritoneal surfaces from any source (operative trauma, infection, foreign bodies, desiccation, irradiation, allergic reaction, or chemical injury) induces a series of biochemical/molecular biologic cascades involving different elements. These elements include peritoneal fluid, neutrophils, leukocytes, macrophages, cytokines, mesothelial cells, and tissue and coagulation factors, which teleologically have the intention of peritoneal repair; however, these processes also result in adhesion development. Major pathways that play significant roles in the healing process of peritoneal damage leading to adhesion development are the fibrinolytic system, extracellular matrix deposition, growth factor and cytokines, cell adhesion molecules, angiogenesis, apoptosis and proliferation, and remesothelialization. Greater understanding of the regulation and interaction of these processes provides the potential for reduction of postoperative adhesion development.

  10. Abdominal acupuncture reduces laser-evoked potentials in healthy subjects

    DEFF Research Database (Denmark)

    Pazzaglia, C.; Liguori, S.; Minciotti, I.

    2015-01-01

    Objective: Acupuncture is known to reduce clinical pain, although the exact mechanism is unknown. The aim of the current study was to investigate the effect of acupuncture on laser-evoked potential amplitudes and laser pain perception. Methods: In order to evaluate whether abdominal acupuncture...... is able to modify pain perception, 10 healthy subjects underwent a protocol in which laser-evoked potentials (LEPs) and laser pain perception were collected before the test (baseline), during abdominal acupuncture, and 15. min after needle removal. The same subjects also underwent a similar protocol...... in which, however, sham acupuncture without any needle penetration was used. Results: During real acupuncture, both N1 and N2/P2 amplitudes were reduced, as compared to baseline (p . < 0.01). The reduction lasted up to 15. min after needle removal. Furthermore, laser pain perception was reduced during...

  11. Abdominal compartment syndrome. Interesting aspects.

    Directory of Open Access Journals (Sweden)

    Nicolás Rubio Silveira

    2004-04-01

    Full Text Available The management of the abdominal compartiment syndrome is still a controversial point nowadays. Its early diagnosis and treatment constitute a challenge for surgeons and physicians at the intensive care unit who have to face these cases . The physiopathologic changes that can occur can lead to the patients death, constituting pulmonary thromboembolism and multiorgan failure the principal causes of death. This paper presents the principal clinical parameters and technical procedures for its diagnosis and treatment with the aim of diminishing its morbi-mortality raits in our hospitals

  12. Peritoneoscopy of the liver after abdominal surgery.

    Directory of Open Access Journals (Sweden)

    Kawaguchi,Kenji

    1983-02-01

    Full Text Available The incidence of intraperitoneal adhesion after abdominal surgery was studied. Peritoneoscopy was performed in 933 patients with liver diseases over the 6 year 5 month period from March 1974 to July 1980. Of the patients, 352 (37.7% had undergone an abdominal operation, and intraperitoneal adhesion was detected in 205 (58.2% of these patients. The liver was not observable in 5 out of 61 patients with adhesions after upper abdominal operations. Whereas, the liver was clearly observable in patients with lower abdominal operations in spite of adhesions. Out of the 581 patients without any abdominal operations, 30 patients (5.2% had adhesions in the abdominal cavity, and 6 of them had extensive adhesions that partially obscured the observation of liver surface. In all patients, peritoneoscopy was performed without complications by avoiding the surgical scar for puncture sites and ensuring a free air lumen before trocar puncture.

  13. Clinical profile of abdominal tuberculosis in children

    OpenAIRE

    Ira Shah; Ramya Uppuluri

    2010-01-01

    Aim: A retrospective study was conducted in children, suffering from abdominal TB, attending Pediatric TB clinic from 2007 to 2009. Materials And Methods: Age-wise distribution and type of abdominal TB were analyzed with clinical features. Results : Out of 285 children with TB, 32 (11.2%) had abdominal tuberculosis. Male: Female ratio was 2.1:1. 7 (21.9%) children were 10 years of age. The most comm...

  14. [Internationalization and innovation of abdominal acupuncture].

    Science.gov (United States)

    Wang, Yong-Zhou

    2013-09-01

    Characteristics of abdominal acupuncture are analyzed through three aspects of inheriting and innovation, collaborated research as well as international visual field. It is pointed that abdominal acupuncture is based on clinical practice, focuses on enhancing the therapeutic effect and expending the clinical application. It also promots the thinking on how to recall the tradition and how to inherit tradition availably. The modern medical problems should be studied and innovation resolutions should be searched, which can help the internationalization and modernization of abdominal acupuncture.

  15. Different Anti-Contractile Function and Nitric Oxide Production of Thoracic and Abdominal Perivascular Adipose Tissues.

    Science.gov (United States)

    Victorio, Jamaira A; Fontes, Milene T; Rossoni, Luciana V; Davel, Ana P

    2016-01-01

    Divergent phenotypes between the perivascular adipose tissue (PVAT) surrounding the abdominal and the thoracic aorta might be implicated in regional aortic differences, such as susceptibility to atherosclerosis. Although PVAT of the thoracic aorta exhibits anti-contractile function, the role of PVAT in the regulation of the vascular tone of the abdominal aorta is not well defined. In the present study, we compared the anti-contractile function, nitric oxide (NO) availability, and reactive oxygen species (ROS) formation in PVAT and vessel walls of abdominal and thoracic aorta. Abdominal and thoracic aortic tissue from male Wistar rats were used to perform functional and molecular experiments. PVAT reduced the contraction evoked by phenylephrine in the absence and presence of endothelium in the thoracic aorta, whereas this anti-contractile effect was not observed in the abdominal aorta. Abdominal PVAT exhibited a reduction in endothelial NO synthase (eNOS) expression compared with thoracic PVAT, without differences in eNOS expression in the vessel walls. In agreement with this result, NO production evaluated in situ using 4,5-diaminofluorescein was less pronounced in abdominal compared with thoracic aortic PVAT, whereas no significant difference was observed for endothelial NO production. Moreover, NOS inhibition with L-NAME enhanced the phenylephrine-induced contraction in endothelial-denuded rings with PVAT from thoracic but not abdominal aorta. ROS formation and lipid peroxidation products evaluated through the quantification of hydroethidine fluorescence and 4-hydroxynonenal adducts, respectively, were similar between PVAT and vessel walls from the abdominal and thoracic aorta. Extracellular superoxide dismutase (SOD) expression was similar between the vessel walls and PVAT of the abdominal and thoracic aorta. However, Mn-SOD levels were reduced, while CuZn-SOD levels were increased in abdominal PVAT compared with thoracic aortic PVAT. In conclusion, our results

  16. Analisa Penggunaan Sinyal Radar Bentuk Pulsa dan Gelombang Kontinyu untuk Target Bergerak dengan Model Clutter Terdistribusi Rayleigh

    Directory of Open Access Journals (Sweden)

    Fery Gustomo

    2013-09-01

    Full Text Available Radar (Radio, Detection, and Ranging mampu mendeteksi target untuk mendapatkan informasi berupa jarak, azimuth, dan kecepatan. Sinyal Radar ada dua jenis, yaitu pulsa (Pulsed Radar dan gelombang kontinyu (Continuous Wave Radar. Pulsed Radar mempunyai prinsip kerja memancarkan sinyal pulsa dengan PRI (Pulse Repetition Interval dan PRF (Pulse Repetition Frequency tertentu dipancarkan dengan modulasi ke dalam sinyal sinusoidal dengan frekuensi yang lebih tinggi serta memanfaatkan delay dari setiap pulsanya untuk mendapatkan informasi dari target. Sedangkan Continuous Wave Radar mempunyai prinsip kerja memancarkan sinyal sinusoidal secara terus menerus dan memanfaatkan sinyal echo yang terdiri dari beberapa variasi frekuensi akibat adanya efek Doppler untuk mendeteksi target. Terdapat pengaruh jenis gelombang sinyal radar terhadap kemampuan deteksi radar. Model distribusi Rayleigh dipilih untuk dapat mewakili suatu kondisi lingkungan (clutter yang bergerak dan mempunyai parameter kecepatan angin. Hasil simulasi dari kedua jenis sinyal menunjukkan bahwa pada model clutter terdistribusi Rayleigh, radar CW mempunyai kemampuan deteksi yang lebih baik pada kecepatan target yang lebih tinggi, karena mampu mendeteksi target dengan kecepatan 20-60 knots. Sedangkan radar pulsa mempunyai kemampuan deteksi yang lebih baik pada kecepatan target rendah yaitu pada kecepatan 15-55 knots. Untuk Probabilitas deteksi minimum 90%, Radar CW mempunyai ketahanan yang lebih baik terhadap noise daripada radar pulsa karena kemampuan radar pulsa terbatas pada nilai SNR 20 dB. Sedangkan radar CW mampu mendeteksi target dengan baik sampai SNR bernilai 15 dB. Sedangkan untuk deteksi terhadap kecepatan target, radar CW mempunyai hasil yang lebih akurat daripada radar pulsa.

  17. Using an improved SIFT algorithm and fuzzy closed-loop control strategy for object recognition in cluttered scenes.

    Science.gov (United States)

    Nie, Haitao; Long, Kehui; Ma, Jun; Yue, Dan; Liu, Jinguo

    2015-01-01

    Partial occlusions, large pose variations, and extreme ambient illumination conditions generally cause the performance degradation of object recognition systems. Therefore, this paper presents a novel approach for fast and robust object recognition in cluttered scenes based on an improved scale invariant feature transform (SIFT) algorithm and a fuzzy closed-loop control method. First, a fast SIFT algorithm is proposed by classifying SIFT features into several clusters based on several attributes computed from the sub-orientation histogram (SOH), in the feature matching phase only features that share nearly the same corresponding attributes are compared. Second, a feature matching step is performed following a prioritized order based on the scale factor, which is calculated between the object image and the target object image, guaranteeing robust feature matching. Finally, a fuzzy closed-loop control strategy is applied to increase the accuracy of the object recognition and is essential for autonomous object manipulation process. Compared to the original SIFT algorithm for object recognition, the result of the proposed method shows that the number of SIFT features extracted from an object has a significant increase, and the computing speed of the object recognition processes increases by more than 40%. The experimental results confirmed that the proposed method performs effectively and accurately in cluttered scenes.

  18. Abdominal Pain in the Geriatric Patient.

    Science.gov (United States)

    Magidson, Phillip D; Martinez, Joseph P

    2016-08-01

    With an aging population, emergency department clinicians can expect an increase in geriatric patients presenting with abdominal pain. Compared with younger patients, this patient population is less likely to present with classic symptoms, physical examination findings, and laboratory values of abdominal disease. However, the morbidity and mortality associated with elderly patients presenting with abdominal pathologic conditions are significant. For this reason, the clinician must be familiar with some subtle and not so subtle differences when caring for the geriatric patient with abdominal pain to ensure timely diagnosis and appropriate treatment.

  19. Abdominal migraine in childhood: a review

    Directory of Open Access Journals (Sweden)

    Scicchitano B

    2014-08-01

    Full Text Available Beatrice Scicchitano,1 Gareth Humphreys,1 Sally G Mitton,2 Thiagarajan Jaiganesh1 1Children's Emergency Department, 2Department of Paediatric Gastroenterology, St Georges Hospital, St Georges Healthcare NHS Trust, Tooting, London, United Kingdom Abstract: The childhood condition of abdominal migraine has been described under many different synonyms, including "abdominal epilepsy", "recurrent abdominal pain", "cyclical vomiting syndrome", and "functional gastrointestinal disorder". In the early literature, abdominal migraine is included in the "childhood periodic syndrome", first described by Wyllie and Schlesinger in 1933. Abdominal migraine has emerged over the last century as a diagnostic entity in its own right thanks to the development of well defined diagnostic criteria and its recent inclusion in the International Headache Society's Classification of Headache disorders. Despite this progress, little is known about the pathophysiology of the condition, and the treatment options are poorly defined. Here we summarize the recent literature, with particular focus on establishing the diagnosis of abdominal migraine and its pathophysiology, and suggest an approach to management. Keywords: abdominal migraine, recurrent abdominal pain, abdominal epilepsy, cyclical vomiting

  20. Percutaneous drainage of abdominal abcess

    Energy Technology Data Exchange (ETDEWEB)

    Men, Sueleyman E-mail: suleyman.men@deu.edu.tr; Akhan, Okan; Koeroglu, Mert

    2002-09-01

    The mortality in undrained abdominal abscesses is high with a mortality rate ranging between 45 and 100%. The outcome in abdominal abscesses, however, has improved due to advances in image guided percutaneous interventional techniques. The main indications for the catheter drainage include treatment or palliation of sepsis associated with an infected fluid collection, and alleviation of the symptoms that may be caused by fluid collections by virtue of their size, like pancreatic pseudocele or lymphocele. The single liver abscesses may be drained with ultrasound guidance only, whereas the multiple abscesses usually require computed tomography (CT) guidance and placement of multiple catheters. The pancreatic abscesses are generally drained routinely and urgently. Non-infected pancreatic pseudocysts may be simply observed unless they are symptomatic or cause problems such as pain or obstruction of the biliary or the gastrointestinal tract. Percutaneous routes that have been described to drain pelvic abscesses include transrectal or transvaginal approach with sonographic guidance, a transgluteal, paracoccygeal-infragluteal, or perineal approach through the greater sciatic foramen with CT guidance. Both the renal and the perirenal abscesses are amenable to percutaneous drainage. Percutaneous drainage provides an effective and safe alternative to more invasive surgical drainage in most patients with psoas abscesses as well.

  1. MR angiography in abdominal neoplasms

    Energy Technology Data Exchange (ETDEWEB)

    Squillaci, E. [Dept. of Radiology, Rome-2 Univ., Hospital S. Eugenio, Rome (Italy); Crecco, M. [Dept. of Radiology, Cancer Research Inst. (Regina Elena), Rome (Italy); Grandinetti, M.L. [Dept. of Radiology, Cancer Research Inst. (Regina Elena), Rome (Italy); Maspes, F. [Dept. of Radiology, Rome-2 Univ., Hospital S. Eugenio, Rome (Italy); Lo Presti, G. [Dept. of Radiology, Rome-2 Univ., Hospital S. Eugenio, Rome (Italy); Squillaci, S. [Dept. of Radiology, Cancer Research Inst. (Regina Elena), Rome (Italy); Simonetti, G. [Dept. of Radiology, Rome-2 Univ., Hospital S. Eugenio, Rome (Italy)

    1994-10-01

    The role of magnetic resonance angiography (MRA) in the evaluation of vascular involvement was studied in 55 patients with abdominal neoplasms. A 2-D time-of-flight (TOF) technique was used in all patients. All patients underwent CT and MR examinations before MRA. Also, MR angiograms were compared with digital subtraction angiography in 22 cases, with Doppler US in 13 cases, and with surgical findings in 20 cases. In all patients with liver neoplasms (n=29) MRA demonstrated the absence of flow in the infiltrated segments. Pericapsular neovascularization was observed in 12 patients. Portal vein involvement was correctly detected in 27 patients. In all cases MRA demonstrated in relationship between the tumor and venous structures. Portosystemic shunts were visualized in 20 of 21 patients with portal hypertension. Vena cava thrombosis (3 cases), compression (5 cases), and displacement (2 cases) were correctly demonstrated. In renal (n=6) and adrenal gland (n=3) tumors renal vein compression was correctly detected in 2 cases, displacement in 1 case, and thrombosis in 3 cases, with only 1 false-positive finding. In 7 patients with pancreatic tumors MRA demonstrated splenic vein thrombosis in 2 cases and compression in 2 cases, with one false-positive finding. Our results indicate that MRA provides precise information regarding venous vascular involvement in abdominal neoplasms, but preoperative arterial mapping is still problematic. (orig.)

  2. Joint statistical correction of clutters, spokes and beam height for a radar derived precipitation climatology in southern Germany

    Directory of Open Access Journals (Sweden)

    A. Wagner

    2012-11-01

    Full Text Available First results of radar derived climatology have emerged over the last years, as datasets of appropriate extent are becoming available. Usually, these statistics are based on time series lasting up to ten years as continuous storage of radar data was often not achieved before. This kind of climatology demands a high level of data quality. Small deviations or minor systematic under- or overestimations in single radar images become a major cause of error in statistical analysis. Extensive corrections of radar data are a crucial prerequisite for radar derived climatology. We present a new statistical post-correction scheme based on a climatological analysis of seven years of radar data of the Munich weather radar (2000–2006 operated by DWD (German Weather Service. Original radar products are used subject only to corrections within the signal processor without any further corrections on single radar images. The aim of this statistical correction is to make up for the average systematic errors caused by clutter, propagation, or measuring effects but to conserve small-scale natural variations in space.

    The statistical correction is based on a thorough analysis of the different causes of possible errors for the Munich weather radar. This analysis revealed the following basic effects: the decrease of rain amount as a function of height and distance from the radar, clutter effects such as clutter remnants after filtering, holes by eliminated clutter or shading effects from obstacles near the radar, visible as spokes, as well as the influence of the bright band. The correction algorithm is correspondingly based on these results. It consists of three modules. The first one is an altitude correction which minimises measuring effects. The second module corrects clutter effects and disturbances and the third one realises a mean adjustment to selected rain gauges. Two different sets of radar products are used. The statistical analysis as well as

  3. Uso da peritoneostomia na sepse abdominal Laparostomy in abdominal sepsis

    Directory of Open Access Journals (Sweden)

    Juvenal da Rocha Torres Neto

    2007-09-01

    Full Text Available Dentre as modalidades terapêuticas da sepse abdominal, a peritoneostomia tem papel decisivo permitindo explorações e lavagens da cavidade de forma facilitada. Observamos pacientes com diagnóstico clínico de sepse abdominal internados no Serviço de Coloproctologia do Hospital Universitário da Universidade Federal de Sergipe, e que foram submetidos a peritoneostomia de janeiro de 2004 a janeiro de 2006. Foram avaliados quanto ao diagnóstico primário e secundário, tipo de peritonite secundária, antibioticoterapia, esquema de lavagens, tempo de peritoneostomia, complicações e desfecho. Estudamos 12 pacientes, com idade de 15 a 57, média de 39,3 anos. Diagnóstico primário: abdome agudo inflamatório em 6(50%, abdome agudo obstrutivo em 2(16,7%, abdome agudo perfurativo em 2(16,7%, fístula enterocutânea em 1(8,3% e abscesso intra-cavitário em 1(8,3%. Diagnóstico secundário: perfuração de cólon em 4(33,3%, abscessos intra-cavitários em 3(25%, deiscências de anastomoses em 3(25%, 1(8,3% com tumor perfurado de sigmóide e 1(8,3% com necrose de cólon abaixado. Peritonite fecal em 10(83,3% e purulenta em 2(16,7%. A antibioticoterapia teve duração média de 19 dias. Lavagens de demanda em 6(50%, programadas em 4(33,3% e regime misto em 2(16,7%. O tempo médio de peritoneostomia foi de 10,9 dias (1-36. Como complicações: evisceração em 2(16,7% e fistulização em 1(8,3%. Quatro pacientes evoluíram com óbito.Among the therapeutics approach form of abdominal sepsis, the laparostomy has a decisive role allowing cavity explorations and lavages in an easier way. We study patients with abdominal sepsis diagnoses admitted to our surgical service of Coloproctology form Sergipe´s Federal University Hospital who underwent a Bogotá Bag laparostomy associated or not with polypropylene mesh from January 2004 to January 2006. These patients were assessed as: first and second diagnosis; secondary peritonitis type; antibiotic

  4. Mesh repair of hernias of the abdominal wall

    NARCIS (Netherlands)

    W.W. Vrijland (Wietske)

    2003-01-01

    textabstractA hernia of the abdominal wall is a permanent or intermittent protrusion of abdominal contents outside the abdominal cavity through a defect in the abdominal wall. Approximately 75% of all hernias occur in the inguinal region. Other types of hernias of the ventral abdominal wall are inci

  5. Mesh repair of hernias of the abdominal wall

    NARCIS (Netherlands)

    W.W. Vrijland (Wietske)

    2003-01-01

    textabstractA hernia of the abdominal wall is a permanent or intermittent protrusion of abdominal contents outside the abdominal cavity through a defect in the abdominal wall. Approximately 75% of all hernias occur in the inguinal region. Other types of hernias of the ventral abdominal wall are inci

  6. Effect of abdominal irradiation on growth in boys treated for a Wilms' tumor

    Energy Technology Data Exchange (ETDEWEB)

    Wallace, W.H.; Shalet, S.M.; Morris-Jones, P.H.; Swindell, R.; Gattamaneni, H.R. (Christie Hospital, Manchester (England))

    1990-01-01

    To study the effect of abdominal irradiation on spinal growth in childhood we have measured final height, sitting height, and leg length in 30 male survivors of a Wilms' tumor. Twenty-one patients received whole abdominal irradiation by either megavoltage therapy (MV: n = 11) or orthovoltage therapy (OV: n = 10); the remainder received flank irradiation. To examine the effect of the adolescent growth spurt on the irradiated spine we have followed prospectively seven patients who received whole abdominal irradiation and nine patients who received flank irradiation through puberty. Compared to a normal population there is a modest reduction in median final standing height SDS (H.SDS: -1.15) accompanied by a marked reduction in median final sitting height SDS (S.HT SDS: -2.41) with no apparent effect on median subischial leg length SDS (SILL.SDS: 0.04). This reduction in spinal growth is reflected by a strongly positive disproportion score (DPS; (SILL SDS-S.HT SDS) + 2.81). The incidence of scoliosis after abdominal irradiation has been low (10%). During puberty there is a significant fall in median sitting height SDS after both whole abdominal (median fall: -0.9, P = 0.02) and flank irradiation (median fall: -1.85, P = 0.01), and this is reflected in a significant increase in disproportion (DPS: whole abdominal; median rise +1.4, P = 0.02: flank, median rise +1.34, P = 0.01). After MV irradiation there is a significant correlation between the degree of disproportion and the age at treatment (P less than 0.0005). The younger the patient is at treatment the more severe is the restriction on spinal growth and the shorter and more disproportionate they become as an adult. The estimated eventual loss in potential height from abdominal irradiation at the age of one is 10 cm and at five years is 7 cm.

  7. Thoraco-abdominal aortic aneurysm branched repair

    NARCIS (Netherlands)

    Verhoeven, E. L. G.; Tielliu, I. F. J.; Ferreira, M.; Zipfel, B.; Adam, D. J.

    2010-01-01

    Open thoraco-abdominal aortic aneurysm repair is a demanding procedure with high impact on the patient and the operating team. Results from expert centres show mortality rates between 3-21%, with extensive morbidity including renal failure and paraplegia. Endovascular repair of abdominal aortic aneu

  8. Actinomycosis mimicking abdominal neoplasm. Case report

    DEFF Research Database (Denmark)

    Waaddegaard, P; Dziegiel, Morten Hanefeld

    1988-01-01

    In a patient with a 6-month history of nonspecific abdominal complaints, preoperative examination indicated malignant disease involving the right ovary, rectum and sigmoid, but laparotomy revealed abdominal actinomycosis. Removal of the ovary and low anterior colonic resection followed by penicil...

  9. Well Leg Compartment Syndrome After Abdominal Surgery

    DEFF Research Database (Denmark)

    Christoffersen, Jens Krogh; Hove, Lars Dahlgaard; Mikkelsen, Kim Lyngby;

    2016-01-01

    BACKGROUND: Well leg compartment syndrome (WLCS) is a complication to abdominal surgery. We aimed to identify risk factors for and outcome of WLCS in Denmark and literature. METHODS: Prospectively collected claims to the Danish Patient Compensation Association (DPCA) concerning WLCS after abdominal...

  10. Abdominal Pain (Stomach Pain), Short-Term

    Science.gov (United States)

    ... in Children and TeensRead MoreBMI Calculator Abdominal Pain (Stomach Pain), Short-termJust about everyone has had a " ... time or another. But sudden severe abdominal pain (stomach pain), also called acute pain, shouldn't be ...

  11. ABDOMINAL WALL DESMOID TUMOUR OVER APPENDICECTOMY SCAR

    OpenAIRE

    Vijaya; Sarbeshwar; Gogoi

    2015-01-01

    BACKGROUND: Desmoid tumors are slow growing deep fibromatoses with aggressive infiltration of adjacent tissue but without any metastatic potential . (1,2,3) CASE PRESENTATION: We report a female patient with desmoid tumor of the abdominal wall over appendicectomy scar w ho underwent primary resection. Preoperative evaluation incl uded abdominal ultrasound, and computed tomography. The histology of this cases revealed a desmoid tumor. CONCLUSION: ...

  12. Recovery after abdominal wall reconstruction

    DEFF Research Database (Denmark)

    Jensen, Kristian Kiim

    2017-01-01

    was lacking. Study II was a case-control study of the effects of an enhanced recovery after surgery pathway for patients undergoing abdominal wall reconstruction for a giant hernia. Sixteen consecutive patients were included prospectively after the implementation of a new enhanced recovery after surgery...... pathway at the Digestive Disease Center, Bispebjerg Hospital, and compared to a control group of 16 patients included retrospectively in the period immediately prior to the implementation of the pathway. The enhanced recovery after surgery pathway included preoperative high-dose steroid, daily assessment...... of revised discharge criteria and an aggressive approach to restore bowel function (chewing gum and enema on postoperative day two). Patients who followed the enhanced recovery after surgery pathway reported low scores of pain, nausea and fatigue, and were discharged significantly faster than patients...

  13. Intra-abdominal pressure during swimming.

    Science.gov (United States)

    Moriyama, S; Ogita, F; Huang, Z; Kurobe, K; Nagira, A; Tanaka, T; Takahashi, H; Hirano, Y

    2014-02-01

    The present study aimed to determine the intra-abdominal pressure during front crawl swimming at different velocities in competitive swimmers and to clarify the relationships between stroke indices and changes in intra-abdominal pressure. The subjects were 7 highly trained competitive collegiate male swimmers. Intra-abdominal pressure was measured during front crawl swimming at 1.0, 1.2 and 1.4 m · s(-1) and during the Valsalva maneuver. Intra-abdominal pressure was taken as the difference between minimum and maximum values, and the mean of 6 stable front crawl stroke cycles was used. Stroke rate and stroke length were also measured as stroke indices. There were significant differences in stroke rate among all velocities (P swimming velocity. These findings do not appear to support the effectiveness of trunk training performed by competitive swimmers aimed at increasing intra-abdominal pressure. © Georg Thieme Verlag KG Stuttgart · New York.

  14. Pulmonary complications of abdominal wall defects.

    Science.gov (United States)

    Panitch, Howard B

    2015-01-01

    The abdominal wall is an integral component of the chest wall. Defects in the ventral abdominal wall alter respiratory mechanics and can impair diaphragm function. Congenital abdominal wall defects also are associated with abnormalities in lung growth and development that lead to pulmonary hypoplasia, pulmonary hypertension, and alterations in thoracic cage formation. Although infants with ventral abdominal wall defects can experience life-threatening pulmonary complications, older children typically experience a more benign respiratory course. Studies of lung and chest wall function in older children and adolescents with congenital abdominal wall defects are few; such investigations could provide strategies for improved respiratory performance, avoidance of respiratory morbidity, and enhanced exercise ability for these children.

  15. Acute spontaneous isolated dissection of abdominal aorta

    Directory of Open Access Journals (Sweden)

    Ali Akbar beigi

    2009-09-01

    Full Text Available

    • Aortic dissection occurs when the layers of the aorta separate as a result of extra luminal cavity of blood through an intimal tear. Dissection limited to the abdominal aorta is rare. Unfortunately, the appropriate management of dissecting aneurysm of abdominal aorta is not documented yet. A 43 years old man was admitted to Al-zahra hospital in Isfahan with sudden onset of periumbilical abdominal pain. CT scan confirmed infrarenal dissection of abdominal aorta. Performing laparotomy, aorta was repaired using bifurcate collagen-coated Dacron graft. Surgical intervention with synthetic graft is recommended in patients with dissecting aortic aneurysm of infrarenal segments where the extent of dissection is limited and accessible.
    • Keywords: Aneurysm, Aortic dissection, Aortic aneurysm abdominal surgery.

  16. Modeling and Simulation of High Resolution Radar Clutter on SIRV%基于SIRV高分辨率雷达杂波建模与仿真

    Institute of Scientific and Technical Information of China (English)

    谢洪森; 周鹏; 栾宝宽; 邹鲲

    2012-01-01

    Modeling and simulation of the high resolution radar clutter is the most important method to evaluate the radar performance. The generalized compound (GO probability density function(PDF) is used to describe the high resolution radar clutter statistics. The GC PDF is formed using the generalized gamma PDF to describe the speckle and modulation components of the radar clutter. The advantageous of radar clutter modeling by use of spherically invariant random vector (SIRV) is that the correlation matrix and marginal PDF of random vectors can be control respectively and independently. In this paper, the GC PDF radar clutter and SIRV modeling methods are discussed, and the SIRV model of the GC PDF radar clutter is proposed. The computer simulation is used to validate the model, and the statistics of the simulated GC-PDF clutter is compared with the theoretical results. The simulation results are identical with the theoretical results, which proves that the SIRV model is of availability and universality.%高分辨率雷达杂波建模与仿真是评估雷达性能的重要手段.广义复合概率密度通常用来描述高分辨率雷达杂波.在广义复合分布中,将散斑分量和调制分量均采用广义伽马(GΓ)分布来表示.采用球不变随机矢量(SIRV)进行杂波建模的优点在于能够独立控制其相关性和一维边缘概率密度.对广义复合分布和SIRV建模方法进行了讨论,在此基础上,给出了相干相关的广义复合分布的SIRV模型,利用计算机进行了广义复合分布的杂波仿真,并对杂波仿真的统计特性与理论值进行了比较.仿真结果与理论分析相吻合,说明了该模型的有效性和普适性.

  17. Abdominal ultrasonography in the diagnostic work-up in children with recurrent abdominal pain

    DEFF Research Database (Denmark)

    Wewer, Anne Vibeke; Strandberg, C; Pærregaard, Anders;

    1997-01-01

    We report on our experience with routine abdominal ultrasonography in 120 children (aged 3-15 years) with recurrent abdominal pain, in order to determine the diagnostic value of this investigation. Eight children (7%) revealed sonographic abnormalities: gallbladder stone (n = 2), splenomegaly (n...... = 1) and urogenital abnormalities (n = 5). The recurrent abdominal pain could be explained by these findings in only two (may be three) cases. CONCLUSION: The diagnostic value of abdominal ultrasonography in unselected children with recurrent abdominal pain is low. However, the direct visualization...... of the abdominal structures as being normal may be helpful to the parents and the child in their understanding and acceptance of the benign nature of recurrent abdominal pain....

  18. Effects of aerobic versus resistance exercise without caloric restriction on abdominal fat, intrahepatic lipid, and insulin sensitivity in obese adolescent boys: a randomized, controlled trial

    Science.gov (United States)

    The optimal exercise modality for reductions of abdominal obesity and risk factors for type 2 diabetes in youth is unknown. We examined the effects of aerobic exercise (AE) versus resistance exercise (RE) without caloric restriction on abdominal adiposity, ectopic fat, and insulin sensitivity and se...

  19. Dynamic changes in thrombin generation in abdominal sepsis in mice.

    Science.gov (United States)

    Wang, Yongzhi; Braun, Oscar O; Zhang, Su; Luo, Lingtao; Norström, Eva; Thorlacius, Henrik

    2014-10-01

    Systemic inflammatory response syndrome and severe infections are associated with major derangements in the coagulation system. The purpose of this study was to examine the dynamic alterations in thrombin generation in abdominal sepsis. Abdominal sepsis was induced by cecal ligation and puncture (CLP) in C57/Bl6 mice. Cecal ligation and puncture caused a systemic inflammatory response, with neutrophil recruitment and tissue damage in the lung as well as thrombocytopenia and leukocytopenia. Thrombin generation, coagulation factors, lung histology, and myeloperoxidase activity was determined 1, 3, 6, and 24 h after induction of CLP. It was found that thrombin generation was increased 1 h after CLP and that thrombin generation started to decrease at 3 h and was markedly reduced 6 and 24 h after CLP induction. Platelet-poor plasma from healthy mice could completely reverse the inhibitory effect of CLP on thrombin generation, suggesting that sepsis caused a decrease in the levels of plasma factors regulating thrombin generation in septic animals. Indeed, it was found that CLP markedly decreased plasma levels of prothrombin, factor V, and factor X at 6 and 24 h. Moreover, we observed that CLP increased plasma levels of activated protein C at 6 h, which returned to baseline levels 24 h after CLP induction. Finally, pretreatment with imipenem/cilastatin attenuated the CLP-evoked decrease in thrombin generation and consumption of prothrombin 24 h after CLP induction. Our novel findings suggest that thrombin generation is initially increased and later decreased in abdominal sepsis. Sepsis-induced reduction in thrombin generation is correlated to changes in the plasma levels of coagulation factors and activated protein C. These findings help explain the dynamic changes in global hemostasis in abdominal sepsis.

  20. Mesh repair of hernias of the abdominal wall

    OpenAIRE

    2003-01-01

    textabstractA hernia of the abdominal wall is a permanent or intermittent protrusion of abdominal contents outside the abdominal cavity through a defect in the abdominal wall. Approximately 75% of all hernias occur in the inguinal region. Other types of hernias of the ventral abdominal wall are incisional, umbilical, epigastric and Spigelian hernia. In chapter 1 an overview of hernias of the abdominal wall is described. The incidence, clinical implications and treatment options and their comp...

  1. [The influence of modern plasma substitutes on the course of abdominal compartment syndrome in patients with abdominal sepsis].

    Science.gov (United States)

    Kursov, S V

    2013-01-01

    The changes of intra-abdominal pressure (IAP) were followed up in 244 patients with abdominal sepsis after operation. The influence of liquid "resuscitation" with different types of plasma substitutes on the rates of IAP was studied and the dependence of changes IAP from filling of vascular bed was investigated. The impedance technique was used to determine the circulating blood volume and its percentage from proper index was estimated according to the sex, age and constitution. The percentage of interstitial liquid in organism was calculated by analogy. The severity of manifestations of abdominal compartment syndrome (ACS) increases with the assessment of severity of the general condition to APACHE-II scale. The most severe ACS course was while using the crystalloid solutions in the complex of infusion therapy. The inclusion of colloids in the infusion therapy facilitated more full volume filling of vascular bed with the liquid, reduced the capillary leakage, accelerated the process of reduction of ACS. The advantage was shown by using the derivatives of hydroxyethylstarch, which promoted the elimination of deficiency of intravascular liquid in the best way.

  2. Core muscle size assessed by perioperative abdominal CT scan is related to mortality, postoperative complications, and hospitalization after major abdominal surgery

    DEFF Research Database (Denmark)

    Hasselager, Rune; Gögenur, Ismail

    2014-01-01

    to systematically review the literature where core muscle size measurements have been used for risk assessment of patients undergoing major abdominal surgery. METHODS: PubMed and EMBASE databases were searched for studies that investigated core muscle size measured with abdominal CT scans and outcomes after major...... abdominal surgery. RESULTS: Eight studies were found. Four studies investigated postoperative complications related to core muscle area. Three of these studies found significantly increased risk of complications related to low core muscle area. Three studies investigated length of hospitalization, and two......PURPOSE: Risk stratification of patients prior to surgery is important for reduction of postoperative morbidity and mortality. The frailty concept has been put forward as a good predictor of surgical outcomes. Sarcopenia (depletion of muscle mass) can be used to measure frailty. We aimed...

  3. Effect of hemodialysis on intra-abdominal pressure Efeito da hemodiálise sobre a pressão intra-abdominal

    Directory of Open Access Journals (Sweden)

    Roberta Fernandes Bonfim

    2007-01-01

    Full Text Available OBJECTIVE: To study the effect of hemodialysis on intra-abdominal pressure. METHODS: Five patients admitted between July and November of 2003 were evaluated in the intensive care unit. Intra-abdominal pressure was measured before and after hemodialysis, maintaining the ventilatory parameters except for PEEP (positive-end expiratory pressure. RESULTS: Intra-abdominal pressure was significantly reduced by hemodialysis in all the 5 patients. CONCLUSION: Hemodialysis significantly reduced intra-abdominal pressure in the 5 patients, an effect which could have influence over other organic systems. This reduction is related to the weight variation before and after hemodialysis, as well as to the loss of volume caused by this procedure.OBJETIVO: Pesquisar o efeito da hemodiálise sobre a pressão intra-abdominal. MÉTODOS: Foram avaliados cinco pacientes internados entre julho e novembro de 2003, na Unidade de Terapia Intensiva do Serviço de Nefrologia do Hospital das Clínicas de São Paulo. Mensurou-se a pressão intra-abdominal antes e após a hemodiálise, mantendo os parâmetros ventilatórios exceto a PEEP (positive end expiratory pressure. RESULTADOS: Constatou-se que a hemodiálise foi capaz de reduzir significativamente a PIA em cinco pacientes na Unidade de Terapia Intensiva CONCLUSÃO: A hemodiálise reduziu a pressão intra-abdominal numa amostra de cinco pacientes, de maneira significativa, o que poderia influenciar os demais sistemas orgânicos. Essa redução está relacionada com a variação de peso pré e pós-hemodiálise, e com a perda de volume promovida pelo procedimento.

  4. Radiologic findings of abdominal wall endometriosis

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Jung Wook [Inje Univ. Ilsan Paik Hospital, Goyang (Korea, Republic of)

    2003-12-01

    To evaluate the imaging findings of abdominal wall endometriosis. In seven of 17 patients with surgically proven endometriosis of the abdominal wall, we retrospectively reviewed the findings of radiologic studies such as abdominal US (n=3), CT (n=4), and MRI (n=1). One patient under went more than one type of imaging, apparently. The surgical history of the seven, and their symptoms and preoperative diagnosis were reviewed, and the size, location, margin and nature of the mass, and the contrast enhancement patterns observed at radiologic studies, were assessed. The chief symptoms were palpable abdominal wall mass (n=5) and lower abdominal pain (n=2) around a surgical scar. Previous surgery included cesarean section (n=5), cesarean section with oophorectomy (n=1) and appendectomy (n=1). Masses were located in the subcutaneous fat layer (n=5) or rectus abdominis muscle (n=2), and their maximum diameter was 2.6 cm. Imaging findings, which correlated closely with the pathologic findings, included a well (n=5) or poorly marginated (n=2) solid mass, with a focal cystic area apparent in two cases. Although imaging findings of abdominal wall endometriosis may not be specific for diagnosis, the presence of a solid abdominal mass in female patients of reproductive age with a history of surgery is a diagnostic pointer.

  5. Traumatic abdominal hernia complicated by necrotizing fasciitis.

    Science.gov (United States)

    Martínez-Pérez, Aleix; Garrigós-Ortega, Gonzalo; Gómez-Abril, Segundo Ángel; Martí-Martínez, Eva; Torres-Sánchez, Teresa

    2014-11-01

    Necrotizing fasciitis is a critical illness involving skin and soft tissues, which may develop after blunt abdominal trauma causing abdominal wall hernia and representing a great challenge for physicians. A 52-year-old man was brought to the emergency department after a road accident, presenting blunt abdominal trauma with a large non-reducible mass in the lower-right abdomen. A first, CT showed abdominal hernia without signs of complication. Three hours after ICU admission, he developed hemodynamic instability. Therefore, a new CT scan was requested, showing signs of hernia complication. He was moved to the operating room where a complete transversal section of an ileal loop was identified. Five hours after surgery, he presented a new episode of hemodynamic instability with signs of skin and soft tissue infection. Due to the high clinical suspicion of necrotizing fasciitis development, wide debridement was performed. Following traumatic abdominal wall hernia (TAWH), patients can present unsuspected injuries in abdominal organs. Helical CT can be falsely negative in the early moments, leading to misdiagnosis. Necrotizing fasciitis is a potentially fatal infection and, consequently, resuscitation measures, wide-spectrum antibiotics, and early surgical debridement are required. This type of fasciitis can develop after blunt abdominal trauma following wall hernia without skin disruption.

  6. Management of intra-abdominal hypertension and abdominal compartment syndrome: a review

    Science.gov (United States)

    2014-01-01

    Patients in the intensive care unit (ICU) are at risk of developing of intra abdominal hypertension (IAH) and abdominal compartment syndrome (ACS). Aim: This review seeks to define IAH and ACS, identify the aetiology and presentation of IAH and ACS, identify IAP measurement techniques, identify current management and discuss the implications of IAH and ACS for nursing practice. A search of the electronic databases was supervised by a health librarian. The electronic data bases Cumulative Index of Nursing and Allied Health Literature (CINAHL); Medline, EMBASE, and the World Wide Web was undertaken from 1996- January 2011 using MeSH and key words which included but not limited to: abdominal compartment syndrome, intra -abdominal hypertension, intra-abdominal pressure in adult populations met the search criteria and were reviewed by three authors using a critical appraisal tool. Data derived from the retrieved material are discussed under the following themes: (1) etiology of intra-abdominal hypertension; (2) strategies for measuring intra-abdominal pressure (3) the manifestation of abdominal compartment syndrome; and (4) the importance of nursing assessment, observation and interventions. Intra-abdominal pressure (IAP) and abdominal compartment syndrome (ACS) have the potential to alter organ perfusion and compromise organ function. PMID:24499574

  7. Visual diagnosis: an 11-month-old with nausea, vomiting, and an abdominal mass.

    Science.gov (United States)

    Whittington, Laura A; Stevens, David C; Jones, Sarah A; Mayo, Julie M

    2013-12-01

    Children with intussusception can present with a wide variety of symptoms, including vomiting, fever,lethargy, and abdominal pain. The classic triad of abdominal pain, hematochezia, and palpable abdominal mass is seen in a few patients.• Early diagnosis of intussusception depends on a high level of clinical suspicion in any child with non specific abdominal findings followed by appropriate radiographic or ultrasonographic evaluation and confirmation with a contrast enema.• Abdominal radiography, although an appropriate component of the initial workup for gastrointestinal symptoms, lacks the sensitivity to reliably exclude the presence of intussusception.• Because ultrasonography is a safe, sensitive, and specific test for the diagnosis of intussusceptions, it should be performed early whenever there is clinical suspicion of intussusception.• Contrast enema is the gold standard for diagnosis and first-line treatment of intussusception. There is an increasing trend for pneumatic reduction of intussusception compared with hydrostatic reduction.Intravenous placement, fluid resuscitation, and notification of the pediatric surgeon should be completed before contrast enema.

  8. [Abdominal tuberculosis in childhood: the clinical manifestations].

    Science.gov (United States)

    Rivera Medina, J; Almendras, M; Devoto, G; Martinez, E; Gonzales, J; Alarcón, P; Muñoz, S

    1993-01-01

    The authors reviewed the histories of 133 patients with abdominal tuberculosis in Instituto Nacional de Salud del Niño (Children's Hospital), Lima, Perú, between 1989 and 1991. We found morbidity higher in scholars (67.4%). Weight lost were present in all cases and malaise in 95.3%, abdominal distension in 83.72% and abdominal pain in 79.06%. Anaemia in 76.06%, ratio albumin/globulin were altered in 74.41% leukocytosis in 67.44%. Evidence of tuberculosis on chest X-ray were detected only in 62.5%.

  9. [Churg-Strauss abdominal manifestation].

    Science.gov (United States)

    Suarez-Moreno, Roberto; Ponce-Pérez, Luis Virgilio; Margain-Paredes, Miguel Angel; Garza-de la Llave, Heriberto; Madrazo-Navarro, Mario; Espinosa-Álvarez, Arturo

    2014-01-01

    Antecedentes: la enfermedad de Churg-Strauss es poco común, idiopática, caracterizada por hipereosinofilia en sangre y tejidos, aunada a vasculitis sistémica en pacientes con antecedentes de asma o rinitis alérgica. Las manifestaciones gastrointestinales del síndrome de Churg Strauss se caracterizan por dolor abdominal, seguido de diarrea y hemorragia en 31-45% de los casos. Caso clínico: paciente masculino con antecedente de asma que acudió a consulta por abdomen agudo con probable apendicitis aguda; durante el protocolo de estudio se diagnosticó síndrome de Churg Strauss, con manifestaciones intestinales. Conclusión: el síndrome de Churg Strauss es una vasculitis poco frecuente que puede manifestarse con síntomas intestinales, como en este caso; es importante tenerlo en mente a la hora de los diagnósticos diferenciales. Existen pocos reportes con este síndrome asociado con abdomen agudo, todos ellos con mal pronóstico.

  10. Outcome of intraoperative goal-directed therapy using Vigileo/FloTrac in high-risk patients scheduled for major abdominal surgeries: A prospective randomized trial

    Directory of Open Access Journals (Sweden)

    Mohammed A. Elgendy

    2017-07-01

    Conclusion: The applied protocol for intraoperative GDT provided significant reduction of PO morbidities, ICU and hospital LOS but couldn‘t significantly reduce mortality rates in high risk patients scheduled for major abdominal surgeries.

  11. SU-E-J-190: Development of Abdominal Compression & Respiratory Guiding System Using Gas Pressure Sensor

    Energy Technology Data Exchange (ETDEWEB)

    Kim, T; Kim, D; Kang, S; Cho, M; Kim, K; Shin, D; Suh, T [The Catholic University of Korea College of Medicine, Seoul (Korea, Republic of); Kim, S [Virginia Commonwealth University, Richmond, VA (United States)

    2015-06-15

    Purpose: Abdominal compression is known to be effective but, often makes external-marker-based monitoring of breathing motion not feasible. In this study, we developed and evaluated a system that enables both abdominal compression and monitoring of residual abdominal motion simultaneously. The system can also provide visual-biofeedback capability. Methods: The system developed consists of a compression belt, an abdominal motion monitoring sensor (gas pressure sensor) and a visual biofeedback device. The compression belt was designed to be able to compress the frontal side of the abdomen. The pressure level of the belt is controlled by air volume and monitored in real time using the gas pressure sensor. The system displays not only the real-time monitoring curve but also a guiding respiration model (e.g., a breath hold or shallow breathing curve) simultaneously on the head mounted display to help patients keep their breathing pattern as consistent as possible. Three healthy volunteers were enrolled in this pilot study and respiratory signals (pressure variations) were obtained both with and without effective abdominal compression to investigate the feasibility of the developed system. Two guidance patterns, breath hold and shallow breathing, were tested. Results: All volunteers showed smaller abdominal motion with compression (about 40% amplitude reduction compared to without compression). However, the system was able to monitor residual abdominal motion for all volunteers. Even under abdominal compression, in addition, it was possible to make the subjects successfully follow the guide patterns using the visual biofeedback system. Conclusion: The developed abdominal compression & respiratory guiding system was feasible for residual abdominal motion management. It is considered that the system can be used for a respiratory motion involved radiation therapy while maintaining the merit of abdominal compression. This work was supported by the Radiation Technology R

  12. Pancreatic insufficiency secondary to abdominal radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Dookeran, K.A.; Thompson, M.M.; Allum, W.H. (Leicester Royal Infirmary (United Kingdom). Dept. of Surgery)

    1993-02-01

    Delayed post-irradiation steatorrhoea secondary to acute pancreatic insufficiency is rare. The authors describe a case occurring in a patient 23 years following radical abdominal radiotherapy for testicular seminoma. (Author).

  13. Abdominal pain - children under age 12

    Science.gov (United States)

    Stomach pain in children; Pain - abdomen - children; Abdominal cramps in children; Belly ache in children ... belly Has had a recent injury to the abdomen Is having trouble breathing Call your provider if ...

  14. [Inflammatory aneurysms of the abdominal aorta].

    Science.gov (United States)

    Tovar Martín, E; Acea Nebril, B

    1993-01-01

    Approximately 10 per cent of abdominal aneurysms have an excessively thick wall that sometimes involve duodenum, cava or colon by an inflammatory process. Between February 1986 and December 1992, 147 patients with abdominal aortic aneurysm (AAA) were treated surgically and in 13 (8.8%) the aneurysms were found to be inflammatory. Their mean age was 67.3 years (70.1 years in non inflammatory group) and all were symptomatics initially (abdominal pain in 53%, rupture in 23%, mass in 15%). The operative mortality for elective resection was 37% in patients with inflammatory abdominal aortic aneurysms (IAAA) decreasing to 9% in the AAA group without inflammatory involvement. We conclude that surgery is indicated in these patients to prevent rupture and to hasten the subsidense of inflammatory process ever with postoperative morbi-mortality increased.

  15. Isolated gallbladder rupture following blunt abdominal trauma

    African Journals Online (AJOL)

    2011-11-03

    Nov 3, 2011 ... partially embedded in the liver substance, cushioned by ... abdominal pains and abrasions on his left hypochondrial region for which he was ... and usually associated with other visceral injuries. Isolated ... teased out Figure 2.

  16. Abdominal separation in an adult male patient with acute abdominal pain

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    We report a male patient with prolonged post-prandial abdominal distension and a sudden onset of epigastric pain initially diagnosed as acute abdomen. The patient had no history of surgery. Physical examination revealed peritonitis and abdominal computed tomography scan showed upper abdominal mesentery intorsion. The patient then underwent surgical intervention. It was found that the descending mesocolon dorsal root was connected to the ascending colon and formed a membrane encapsulating the small intestine...

  17. Abdominal Wall Hernias: Various Imaging Features Correlated with the Anatomy of Abdominal Wall at MDCT

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Shin Young; Shin, Hyeong Cheol; Kim, Sang Won; Kim, Il Young; Kim, Young Tong [Soonchunhyang University Cheonan Hospital, Cheonan (Korea, Republic of)

    2009-07-15

    Abdominal wall hernias are a common condition. However, they may develop acute complications and require surgical correction in most cases. Hence, the correct radiological examination is requisite for an accurate diagnosis. A multi-detector row CT (MDCT) provides an accurate identification of the anatomy of the abdominal wall, precise hernia type, and helps in the detection of early signs of complication. We report various imaging features of abdominal wall hernias via a MDCT.

  18. [Intestinal occlusion and abdominal compartment syndrome (ACS)].

    Science.gov (United States)

    Stagnitti, Franco

    2009-01-01

    Intestinal occlusion is defined as an independent predictive factor of intra-abdominal hypertension (IAH) which represents an independent predictor of mortality. Baggot in 1951 classified patients operated with intestinal occlusion as being at risk for IAH ("abdominal blow-out"), recommending them for open abdomen surgery proposed by Ogilvie. Abdominal surgery provokes IAH in 44.7% of cases with mortality which, in emergency, triples with respect to elective surgery (21.9% vs 6.8%). In particular, IAH is present in 61.2% of ileus and bowel distension and is responsible for 52% of mortality (54.8% in cases with intra-abdominal infection). These patients present with an increasing intra-abdominal pressure (IAP) which, over 20-25 mmHg, triggers an Abdominal Compartment Syndrome (ACS) with altered functions in some organs arriving at Multiple Organ Dysfunction Syndrome (MODS). The intestine normally covers 58% of abdominal volume but when there is ileus distension, intestinal pneumatosis develops (third space) which can occupy up to 90% of the entire cavity. At this moment, Gastro Intestinal Failure (GIF) can appear, which is a specific independent risk factor of mortality, motor of "Organ Failure". The pathophysiological evolution has many factors in 45% of cases: intestinal pneumatosis is associated with mucosal and serous edema, capillary leakage with an increase in extra-cellular volume and peritoneal fluid collections (fourth space). The successive loss of the mucous barrier permits a bacterial translocation which includes bacteria, toxins, pro-inflammatory factors and oxygen free radicals facilitating the passage from an intra-abdominal to inter-systemic vicious cyrcle. IAH provokes the raising of the diaphragm, and vascular and visceral compressions which induce hypertension in the various spaces with compartmental characteristics. These trigger hypertension in the renal, hepatic, pelvic, thoracic, cardiac, intracranial, orbital and lower extremity areas, giving

  19. 机载MIMO 雷达3-CAP杂波抑制方法%3-CAP Clutter Suppression Method Research for Airborne Radar

    Institute of Scientific and Technical Information of China (English)

    郝琳; 张永顺; 李哲

    2014-01-01

    To solve the problem of clutter suppression faced by airborned MIMO radar,after considering the element error,channel uncertainty as well as clutter fluctuation,,the clutter model for airborne MIMO ra-dar under different error conditions is established,a new space-time adaptive processing method based on MIMO systems---M3-CAP method is proposed.Firstly,temporal filtering is performed on the space-time received data,and then the output data of three Doppler channels which are the detected Doppler channel and two of its adj acent channels,is adaptively filtered .By combining MIMO systems and 3-CAP method ef-fectively,the advantage of waveform diversity is extended into 3-CAP method,this new method improves the degree of freedom and clutter estimation accuracy.By analyzing and comparing the clutter suppression performance under different radar systems and different error conditions,the result turns out:the clutter suppression performance of M3-CAP method is superior to JDL-GMB、Modified JDL、3-CAP methods.%针对机载雷达面临的杂波抑制问题,在考虑阵元误差、通道误差和杂波起伏等误差因素对杂波特性影响的基础上,建立了机载 MIMO 雷达杂波数学模型,提出了一种基于 MIMO 雷达体制下的空时自适应新方法---M3-CAP方法。对接收信号进行时域滤波,选取被检测通道与其2个相邻通道为一组,进行自适应处理。该方法通过MIMO 技术与3-CAP 方法的有效结合,将波形分集的优势扩展到3-CAP方法中,显著提高了雷达系统自由度和杂波协方差矩阵估计精度。通过对不同雷达体制以及不同误差条件下杂波抑制性能的分析比较,结果表明:提出的M3-CAP方法的杂波抑制性能明显优于JDL-GMB、改进的JDL、3-CAP等方法。

  20. MR imaging of abdominal mass in children

    Energy Technology Data Exchange (ETDEWEB)

    Araki, Tsutomu [Yamanashi Medical Univ., Tamaho (Japan)

    1995-12-01

    In order to evaluate the usefulness of MR imaging in the diagnosis of abdominal mass in children, we compared MR imaging with CT in 33 children who had undergone both examinations. Although MR imaging was less specific to calcification, gas and fat, it was more specific to hematoma and clarified the extension of tumors more precisely than CT. MRI seems to be a promising diagnostic modality for pediatric abdominal masses. (author).

  1. A focus on intra-abdominal infections

    Directory of Open Access Journals (Sweden)

    Sartelli Massimo

    2010-03-01

    Full Text Available Abstract Complicated intra-abdominal infections are an important cause of morbidity and are frequently associated with poor prognosis, particularly in higher risk patients. Well defined evidence-based recommendations for intra-abdominal infections treatment are partially lacking because of the limited number of randomized-controlled trials. Factors consistently associated with poor outcomes in patients with intra-abdominal infections include increased illness severity, failed source control, inadequate empiric antimicrobial therapy and healthcare-acquired infection. Early prognostic evaluation of complicated intra-abdominal infections is important to select high-risk patients for more aggressive therapeutic procedures. The cornerstones in the management of complicated intra-abdominal infections are both source control and antibiotic therapy. The timing and the adequacy of source control are the most important issues in the management of intra-abdominal infections, because inadequate and late control of septic source may have a negative effect on the outcomes. Recent advances in interventional and more aggressive techniques could significantly decrease the morbidity and mortality of physiologically severe complicated intra-abdominal infections, even if these are still being debated and are yet not validated by limited prospective trials. Empiric antimicrobial therapy is nevertheless important in the overall management of intra-abdominal infections. Inappropriate antibiotic therapy may result in poor patient outcomes and in the appearance of bacterial resistance. Antimicrobial management is generally standardised and many regimens, either with monotherapy or combination therapy, have proven their efficacy. Routine coverage especially against Enterococci and candida spp is not always recommended, but can be useful in particular clinical conditions. A de escalation approach may be recommended in patients with specific risk factors for multidrug

  2. [Late primary abdominal pregnancy. Case report].

    Science.gov (United States)

    Farías, Emigdio Torres; Gómez, Luis Guillermo Torres; Allegre, René Márquez; Higareda, Salvador Hernández

    2008-09-01

    Abdominal advanced pregnancy is an obstetric complication that put at risk maternal and fetal life. We report a case of advanced abdominal pregnancy with intact ovaries and fallopian tubes, without ureteroperitoneal fistulae and, late prenatal diagnosis, in a multiparous patient without risk factors, with alive newborn, and whose pregnancy was attended at Unidad Medica de Alta Especialidad, Hospital de Gineco-Obstetricia, Centro Medico Nacional de Occidente del IMSS, Guadalajara, Jalisco, México.

  3. Surveillance intervals for small abdominal aortic aneurysms

    DEFF Research Database (Denmark)

    Bown, Matthew J; Sweeting, Michael J; Brown, Louise C

    2013-01-01

    Small abdominal aortic aneurysms (AAAs [3.0 cm-5.4 cm in diameter]) are monitored by ultrasound surveillance. The intervals between surveillance scans should be chosen to detect an expanding aneurysm prior to rupture.......Small abdominal aortic aneurysms (AAAs [3.0 cm-5.4 cm in diameter]) are monitored by ultrasound surveillance. The intervals between surveillance scans should be chosen to detect an expanding aneurysm prior to rupture....

  4. Abdominal epilepsy and foreign body in the abdomen--dilemma in diagnosis of abdominal pain.

    Science.gov (United States)

    Topno, Noor; Gopasetty, Mahesh S; Kudva, Annappa; B, Lokesh

    2005-12-31

    There are many medical causes of abdominal pain; abdominal epilepsy is one of the rarer causes. It is a form of temporal lobe epilepsy presenting with abdominal aura. Temporal lobe epilepsy is often idiopathic, however it may be associated with mesial temporal lobe sclerosis, dysembryoplastic neuroepithelial tumors and other benign tumors, arterio-venous malformations, gliomas, neuronal migration defects or gliotic damage as a result of encephalitis. When associated with anatomical abnormality, abdominal epilepsy is difficult to control with medication alone. In such cases, appropriate neurosurgery can provide a cure or, at least, make this condition easier to treat with medication. Once all known intra-abdominal causes have been ruled out, many cases of abdominal pain are dubbed as functional. If clinicians are not aware of abdominal epilepsy, this diagnosis is easily missed, resulting in inappropriate treatment. We present a case report of a middle aged woman presenting with abdominal pain and episodes of unconsciousness. On evaluation she was found to have an intra-abdominal foreign body (needle). Nevertheless, the presence of this entity was insufficient to explain her episodes of unconsciousness. On detailed analysis of her medical history and after appropriate investigations, she was diagnosed with temporal lobe epilepsy which was treated with appropriate medications, and which resulted in her pain being relieved.

  5. Readjustment of abdominal computed tomography protocols in a university hospital: impact on radiation dose

    Energy Technology Data Exchange (ETDEWEB)

    Romano, Ricardo Francisco Tavares; Salvadori, Priscila Silveira; Torres, Lucas Rios; Bretas, Elisa Almeida Sathler; Bekhor, Daniel; Medeiros, Regina Bitelli; D' Ippolito, Giuseppe, E-mail: ricardo.romano@unifesp.br [Universidade Federal de Sao Paulo (EPM/UNIFESP), Sao Paulo, SP (Brazil). Escola Paulista de Medicina; Caldana, Rogerio Pedreschi [Fleury Medicina e Saude, Sao Paulo, SP (Brazil)

    2015-09-15

    Objective: To assess the reduction of estimated radiation dose in abdominal computed tomography following the implementation of new scan protocols on the basis of clinical suspicion and of adjusted images acquisition parameters. Materials and Methods: Retrospective and prospective review of reports on radiation dose from abdominal CT scans performed three months before (group A - 551 studies) and three months after (group B - 788 studies) implementation of new scan protocols proposed as a function of clinical indications. Also, the images acquisition parameters were adjusted to reduce the radiation dose at each scan phase. The groups were compared for mean number of acquisition phases, mean CTDI{sub vol} per phase, mean DLP per phase, and mean DLP per scan. Results: A significant reduction was observed for group B as regards all the analyzed aspects, as follows: 33.9%, 25.0%, 27.0% and 52.5%, respectively for number of acquisition phases, CTDI{sub vol} per phase, DLP per phase and DLP per scan (p < 0.001). Conclusion: The rational use of abdominal computed tomography scan phases based on the clinical suspicion in conjunction with the adjusted images acquisition parameters allows for a 50% reduction in the radiation dose from abdominal computed tomography scans. (author)

  6. MCMC Particle Filter Using New Data Association Technique with Viterbi Filtered Gate Method for Multi-Target Tracking in Heavy Clutter

    Directory of Open Access Journals (Sweden)

    E. M.Saad

    2011-08-01

    Full Text Available Improving data association technique in dense clutter environment for multi-target tracking used in Markov chain Monte Carlo based particle filter (MCMC-PF are discussed in this paper. A new method named Viterbi filtered gate Markov chain Monte Carlo VFG-MCMC is introduced to avoid track swap and to overcome the issue of loosing track to highly maneuvering targets in the presence of more background clutter and false signals. An adaptive search based on Viterbi algorithm is then used to detect the valid filtered data point in each target gate. The detected valid point for each target is applied to the estimation algorithm of MCMC-PF during calculating the sampling weights. This proposed method makes the MCMC interacts only with the valid target that is candidate from the filtered gate and no more calculations are considered for invalid targets. Simulation results demonstrate the effectiveness and better performance when compared to conventional algorithm MCMC-PF.

  7. Poverty Reduction

    OpenAIRE

    Ortiz, Isabel

    2007-01-01

    The paper reviews poverty trends and measurements, poverty reduction in historical perspective, the poverty-inequality-growth debate, national poverty reduction strategies, criticisms of the agenda and the need for redistribution, international policies for poverty reduction, and ultimately understanding poverty at a global scale. It belongs to a series of backgrounders developed at Joseph Stiglitz's Initiative for Policy Dialogue.

  8. A Ground Clutter Cancellation Algorithm for Noise Radar%一种噪声雷达地杂波消除算法

    Institute of Scientific and Technical Information of China (English)

    靳晓艳; 李伟

    2016-01-01

    Due to its excellent anti⁃interference performance and low intercept rate,noise radar has great apply potential in both military and civilian fields.In solve the problem of ground clutter wave cancellation in noise radar,an algorithm based on clutter base orthogonalization is proposed.In this algorithm,receive signal is put into a lattice filter,in order to fit the unknown or time⁃varying statis⁃tics characteristic of the ground clutter.And the parameters of filter are adjusted adaptively.Simulation results indicate that the proposed algorithm not only provides good cancellation effect to the ground clutter,but also can effectively suppress the direct signal.%噪声雷达因其优异的抗干扰性能和低截获概率,在军事和民用领域均具有着巨大的应用潜力。针对噪声雷达地杂波消除困难的问题,提出了一种基于杂波基向量正交化的算法,该算法通过将接收信号输入格形滤波器,并自适应地调整滤波器的参数,以适应地面杂波未知的或随时间变换的统计特性,从而实现最优滤波。仿真结果表明,所提算法不仅对地杂波具有很好的消除效果,与此同时也能够有效抑制直达波。

  9. Childhood abdominal pain in primary care : design and patient selection of the HONEUR abdominal pain cohort

    NARCIS (Netherlands)

    Spee, Leo A A; van den Hurk, Arjan P J M; van Leeuwen, Yvonne; Benninga, Marc A; Bierma-Zeinstra, Sita M A; Passchier, Jan; Berger, Marjolein Y

    2010-01-01

    BACKGROUND: Abdominal pain in children is a common complaint presented to the GP. However, the prognosis and prognostic factors of childhood abdominal pain are almost exclusively studied in referred children. This cohort study aims at describing prognosis and prognostic factors of childhood abdomina

  10. General Considerations of Ruptured Abdominal Aortic Aneurysm: Ruptured Abdominal Aortic Aneurysm

    OpenAIRE

    Lee, Chung Won; Bae, Miju; Chung, Sung Woon

    2015-01-01

    Although development of surgical technique and critical care, ruptured abdominal aortic aneurysm still carries a high mortality. In order to obtain good results, various efforts have been attempted. This paper reviews initial management of ruptured abdominal aortic aneurysm and discuss the key point open surgical repair and endovascular aneurysm repair.

  11. Abdominal Compartment Syndrome and Intra-abdominal Ischemia in Patients with Severe Acute Pancreatitis

    NARCIS (Netherlands)

    Smit, M.; Buddingh, K. T.; Bosma, B.; Nieuwenhuijs, V. B.; Hofker, H. S.; Zijlstra, J. G.

    Severe acute pancreatitis may be complicated by intra-abdominal hypertension (IAH), abdominal compartment syndrome (ACS), and intestinal ischemia. The aim of this retrospective study is to describe the incidence, treatment, and outcome of patients with severe acute pancreatitis and ACS, in

  12. Abdominal Compartment Syndrome and Intra-abdominal Ischemia in Patients with Severe Acute Pancreatitis

    NARCIS (Netherlands)

    Smit, M.; Buddingh, K. T.; Bosma, B; Nieuwenhuijs, V B; Hofker, H.S.; Zijlstra, J.G.

    2016-01-01

    INTRODUCTION: Severe acute pancreatitis may be complicated by intra-abdominal hypertension (IAH), abdominal compartment syndrome (ACS), and intestinal ischemia. The aim of this retrospective study is to describe the incidence, treatment, and outcome of patients with severe acute pancreatitis and ACS

  13. Abdominal Compartment Syndrome and Intra-abdominal Ischemia in Patients with Severe Acute Pancreatitis

    NARCIS (Netherlands)

    Smit, M.; Buddingh, K. T.; Bosma, B.; Nieuwenhuijs, V. B.; Hofker, H. S.; Zijlstra, J. G.

    2016-01-01

    Severe acute pancreatitis may be complicated by intra-abdominal hypertension (IAH), abdominal compartment syndrome (ACS), and intestinal ischemia. The aim of this retrospective study is to describe the incidence, treatment, and outcome of patients with severe acute pancreatitis and ACS, in particula

  14. Abdominal binders may reduce pain and improve physical function after major abdominal surgery - a systematic review

    DEFF Research Database (Denmark)

    Rothman, Josephine Philip; Gunnarsson, Ulf; Bisgaard, Thue

    2014-01-01

    . The PubMed, EMBASE and Cochrane databases were searched for studies on the use of abdominal binders after abdominal surgery or abdominoplasty. All types of clinical studies were included. Two independent assessors evaluated the scientific quality of the studies. The primary outcomes were pain, seroma...

  15. Abdominal obesity can induce both systemic and follicular fluid oxidative stress independent from polycystic ovary syndrome.

    Science.gov (United States)

    Nasiri, Nahid; Moini, Ashraf; Eftekhari-Yazdi, Poopak; Karimian, Leila; Salman-Yazdi, Reza; Zolfaghari, Zahra; Arabipoor, Arezoo

    2015-01-01

    The abdominal form of obesity is prevalent in women with polycystic ovary syndrome (PCOS). Visceral fat accumulation seems to play an important role in etiology of PCOS. In this cross-sectional study we evaluated the association of oxidative stress (OS) induced with PCOS and abdominal obesity in serum and follicular fluid (FF) of infertile women. A total of 80 women younger than 37 years old undergoing an IVF program were studied in the same period of time from September 2012 to October 2013. Blood serum and FF obtained from 40 women with PCOS (diagnosed by the Rotterdam 2004 criteria) and 40 women without PCOS undergoing IVF were evaluated for two OS markers: lipid peroxide (LPO) and total antioxidant capacity (TAC), after puncture. The patients were divided into 4 groups on the basis of presence of PCOS and waist-to-hip ratio (WHR) or abdominal obesity (OA). Healthy and PCOS women with abdominal obesity had significantly higher amounts of LPO in the serum and FF as compared with women without abdominal obesity. LPO concentration in FF was significantly lower than in serum and corroborates the hypothesis that the germinal cells have a potent antioxidant mechanism. We also found that LPO concentration in the PCOS group associated with AO had an increasing trend vs. those AO patients without PCOS but this difference was not significant, so the increase in LPO level was approximately independent of PCOS. Based on our results, the association and interaction between PCOS and AO can lead to TAC concentration reduction in patients. Abdominal obesity can induce local and systemic oxidative stress in PCOS and non-PCOS patients. We suggest that PCOS-induced disorders are likely to be exacerbated in the presence of abdominal obesity. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  16. Focused Assessment with Sonography in Trauma and Abdominal Computed Tomography Utilization in Adult Trauma Patients: Trends over the Last Decade

    Directory of Open Access Journals (Sweden)

    Alexander Y. Sheng

    2013-01-01

    Full Text Available Objective. We sought to describe the trend in abdominal CT use in adult trauma patients after a point-of-care emergency ultrasound program was introduced. We hypothesized that abdominal CT use would decrease as FAST use increased. Methods. We performed a retrospective study of 19940 consecutive trauma patients over the age of 18 admitted to our level one trauma center from 2002 through 2011. Data was collected retrospectively and recorded in a trauma registry. We plotted the rate of FAST and abdominal CT utilization over time. Head CT was used as a surrogate for overall CT utilization rates during the study period. Results. Use of FAST increased by an average of 2.3% (95% CI 2.1 to 2.5, P<0.01 while abdominal CT use decreased by the same rate annually. The percentage of patients who received FAST as the sole imaging modality for the abdomen rose from 2.0% to 21.9% while those who only received an abdominal CT dropped from 21.7% to 2.3%. Conclusions. Abdominal CT use in our cohort declined while FAST utilization grew in the last decade. The rising use of FAST may have played a role in the reduction of abdominal CT performed as decline in CT utilization appears contrary to overall trends.

  17. Effects of ovariohysterectomy on intra-abdominal pressure and abdominal perfusion pressure in cats.

    Science.gov (United States)

    Bosch, L; Rivera del Álamo, M M; Andaluz, A; Monreal, L; Torrente, C; García-Arnas, F; Fresno, L

    2012-12-15

    Intra-abdominal pressure (IAP) and abdominal perfusion pressure (APP) have shown clinical relevance in monitoring critically ill human beings submitted to abdominal surgery. Only a few studies have been performed in veterinary medicine. The aim of this study was to assess how pregnancy and abdominal surgery may affect IAP and APP in healthy cats. For this purpose, pregnant (n=10) and non-pregnant (n=11) queens undergoing elective spaying, and tomcats (n=20, used as controls) presented for neutering by scrotal orchidectomy were included in the study. IAP, mean arterial blood pressure (MAP), APP, heart rate and rectal temperature (RT) were determined before, immediately after, and four hours after surgery. IAP increased significantly immediately after abdominal surgery in both female groups when compared with baseline (PPregnancy did not seem to affect IAP in this population of cats, possibly due to subjects being in early stages of pregnancy.

  18. Intra-abdominal pressure: an integrative review.

    Science.gov (United States)

    Milanesi, Rafaela; Caregnato, Rita Catalina Aquino

    2016-01-01

    There is a growing request for measuring intra-abdominal pressure in critically ill patients with acute abdominal pain to be clarified. Summarizing the research results on measurement of vesical intra-abdominal pressure and analyzing the level of evidence were the purposes of this integrative literature review, carried out based on the databases LILACS, MEDLINE and PubMed, from 2005 to July 2012. Twenty articles were identified, in that, 12 literature reviews, 4 descriptive and exploratory studies, 2 expert opinions, one prospective cohort study and one was an experience report. The vesical intra-abdominal pressure measurement was considered gold standard. There are variations in the technique however, but some common points were identified: complete supine position, in absence of abdominal contracture, in the end of expiration and expressed in mmHg. Most research results indicate keeping the transducer zeroed at the level of the mid-axillary line at the iliac crest level, and instill 25mL of sterile saline. Strong evidence must be developed. RESUMO Em pacientes críticos com quadros abdominais agudos a esclarecer é crescente a solicitação da aferição da pressão intra-abdominal. Sintetizar resultados de pesquisas sobre a mensuração da pressão intra-abdominal pela via vesical e analisar o nível de evidência foram os objetivos desta revisão integrativa da literatura, realizada nas bases LILACS, MEDLINE e PubMed, no período de 2005 a julho de 2012. Identificaram-se 20 artigos, sendo 12 revisões de literatura, 4 estudos exploratório-descritivos, 2 opiniões de especialistas, 1 estudo de coorte prospectivo e 1 relato de experiência. O método vesical para mensuração da pressão intra-abdominal foi considerado padrão-ouro. Existem variações na técnica, entretanto pontos em comum foram identificados: posição supina completa, na ausência de contratura abdominal, ao final da expiração e expressa em mmHg. A maioria indica posicionar o ponto zero do

  19. Exogenous pulmonary surfactant prevents the development of intra-abdominal adhesions in rats.

    Science.gov (United States)

    Schanaider, Alberto; Cotta-Pereira, Ricardo; Silva, Paulo C; Macedo-Ramos, Hugo; Silva, Johnatas D; Teixeira, Pedro A C; Pannain, Vera L N; Rocco, Patricia R M; Baetas-da-Cruz, Wagner

    2016-04-01

    Intra-abdominal adhesions are major post-operative complications for which no effective means of prevention is available. We aimed to evaluate the efficacy of exogenous pulmonary surfactant administration in the prevention of post-operative abdominal adhesions. Rats were randomly assigned to undergo laparotomy (L) or gastroenterostomy (GE) and then treated with surfactant (groups L-S and GE-S, respectively). Intra-abdominal adhesions, collagen fibre content, metalloproteinase (MMP)-9, expression of growth factors (TGF-β, KGF and VEGF), type III procollagen (PCIII) and pro-caspase 3, as well as isolectin B4 and ED1-positive cells expressing MMP-9, were evaluated. Groups treated with surfactant (GE-S and L-S) exhibited fewer adhesions. A significant reduction in collagen fibre content was observed in GE-S compared to GE animals (P abdominal adhesions triggered by laparotomy and gastrointestinal anastomosis, thus preventing fibrosis formation at the peritoneal surfaces. This preclinical study suggests an innovative treatment strategy for intra-abdominal adhesions with surfactant and to endorse its putative mechanism of action.

  20. The effect of food consumption on the thickness of abdominal muscles, employing ultrasound measurements.

    Science.gov (United States)

    Kordi, Ramin; Rostami, Mohsen; Noormohammadpour, Pardis; Mansournia, Mohammad Ali

    2011-08-01

    Recently, the roles of transabdominal muscles particularly TrA (transverse abdominis) muscle in spinal stability leading to treatment of low back pain have been suggested. Both in clinical setting and follow up studies, abdominal muscle thickness measurements need to be repeated at a later point in time to demonstrate efficacy of a therapeutic intervention. Different issues have been suggested as source of error in the repeated measurements of abdominal muscle thickness in different days such as patient position and stability of probe location. The level of stomach fullness has not been investigated as a source of error in ultrasonic measurements of transabdominal muscles thickness. This study was performed to evaluate the effect of food consumption on thickness of lateral abdominal muscles. Lateral abdominal muscles thicknesses of 63 healthy volunteer men were measured before and after food consumption. All the measurements were performed in two transducer positions and both sides. Waist circumference and body weight of participants were also measured before and post-food consumption. The thickness measures of all three muscles layers of lateral abdominal muscles (external oblique, internal oblique and transversus abdominis) in both sides and measured positions were significantly reduced after food consumption. We found no correlation between the increase of waist circumference and reduction of muscle layer thicknesses after food consumption. In case of comparison between the values of transabdominal muscle thicknesses over the time, the effect of food consumption on muscle thickness might be assumed as a potential source of error.

  1. Abdominal aorta transplantation after programmed cryopreservation

    Institute of Scientific and Technical Information of China (English)

    Song Gu; Chang-Jian Liu; Tong Qiao; Xue-Mei Sun; Jun-Hao Chen

    2004-01-01

    AIM: To study the morphologic and cellular immunologic changes after homologous transplantation of the abdominal aorta in rats after programmed cryopreservation (-196°C).METHODS: Abdominal aorta was harvested from anesthetized Spraque Dawley (SD) rats for cryopreservation (group B) or immediate implantation (group A). The survival rates and apoptotic rates of aortic endothelial cells (ECs)were examined. The patency rates, histology and cellular immunologic changes of the abdominal aorta were examined on days 1, 3, 7, 14, 30, 60 after transplantation respectively.RESULTS: The survival rate of ECs after programmed cryopreservation was 90.1±1.79%, about 3.4% lower than that of uncryopreservation (93.5±1.96%). The apoptotic rates of ECs was increased after cryopreservation (7.15%vs 4.86%, P<0.05). The patency rate of group B was significantly higher than that of group A (91.6±12.9% vs 62.5±26.2%, P<0.01). CD4/CD8 ratio, TCR αβ and CD11b/CD18 ratio of group B were significantly lower than those of group A (P<0.05). Revivification of the cryopreserved abdominal aorta showed normal adventitia and intact smooth muscle cells.CONCLUSION: Cryopreservation can reduce homologous abdominal aortic antigenecity. Even if without administration of immunosuppressive agents, it is still feasible to implement homologous artery grafting in rats.

  2. Methods of patient warming during abdominal surgery.

    Directory of Open Access Journals (Sweden)

    Li Shao

    Full Text Available BACKGROUND: Keeping abdominal surgery patients warm is common and warming methods are needed in power outages during natural disasters. We aimed to evaluate the efficacy of low-cost, low-power warming methods for maintaining normothermia in abdominal surgery patients. METHODS: Patients (n = 160 scheduled for elective abdominal surgery were included in this prospective clinical study. Five warming methods were applied: heated blood transfusion/fluid infusion vs. unheated; wrapping patients vs. not wrapping; applying moist dressings, heated or not; surgical field rinse heated or not; and applying heating blankets or not. Patients' nasopharyngeal and rectal temperatures were recorded to evaluate warming efficacy. Significant differences were found in mean temperatures of warmed patients compared to those not warmed. RESULTS: When we compared temperatures of abdominal surgery patient groups receiving three specific warming methods with temperatures of control groups not receiving these methods, significant differences were revealed in temperatures maintained during the surgeries between the warmed groups and controls. DISCUSSION: The value of maintaining normothermia in patients undergoing abdominal surgery under general anesthesia is accepted. Three effective economical and practically applicable warming methods are combined body wrapping and heating blanket; combined body wrapping, heated moist dressings, and heating blanket; combined body wrapping, heated moist dressings, and warmed surgical rinse fluid, with or without heating blanket. These methods are practically applicable when low-cost method is indeed needed.

  3. Imaging the Abdominal Manifestations of Cystic Fibrosis

    Directory of Open Access Journals (Sweden)

    C. D. Gillespie

    2017-01-01

    Full Text Available Cystic fibrosis (CF is a multisystem disease with a range of abdominal manifestations including those involving the liver, pancreas, and kidneys. Recent advances in management of the respiratory complications of the disease has led to a greater life expectancy in patients with CF. Subsequently, there is increasing focus on the impact of abdominal disease on quality of life and survival. Liver cirrhosis is the most important extrapulmonary cause of death in CF, yet significant challenges remain in the diagnosis of CF related liver disease. The capacity to predict those patients at risk of developing cirrhosis remains a significant challenge. We review representative abdominal imaging findings in patients with CF selected from the records of two academic health centres, with a view to increasing familiarity with the abdominal manifestations of the disease. We review their presentation and expected imaging findings, with a focus on the challenges facing diagnosis of the hepatic manifestations of the disease. An increased familiarity with these abdominal manifestations will facilitate timely diagnosis and management, which is paramount to further improving outcomes for patients with cystic fibrosis.

  4. Postoperative abdominal complications after cardiopulmonary bypass

    Directory of Open Access Journals (Sweden)

    Dong Guohua

    2012-10-01

    Full Text Available Abstract Background To summarize the diagnostic and therapeutic experiences on the patients who suffered abdominal complications after cardiovascular surgery with cardiopulmonary bypass(CPB. Methods A total of 2349 consecutive patients submitted to cardiovascular surgery with CPB in our hospital from Jan 2004 to Dec 2010 were involved. The clinical data of any abdominal complication, including its incidence, characters, relative risks, diagnostic measures, medical or surgical management and mortality, was retrospectively analyzed. Results Of all the patients, 33(1.4% developed abdominal complications postoperatively, including 11(33.3% cases of paralytic ileus, 9(27.3% of gastrointestinal haemorrhage, 2(6.1% of gastroduodenal ulcer perforation, 2(6.1% of acute calculus cholecystitis, 3(9.1% of acute acalculus cholecystitis, 4(12.1% of hepatic dysfunction and 2(6.1% of ischemia bowel diseases. Of the 33 patients, 26 (78.8% accepted medical treatment and 7 (21.2% underwent subsequent surgical intervention. There were 5(15.2% deaths in this series, which was significantly higher than the overall mortality (2.7%. Positive history of peptic ulcer, advanced ages, bad heart function, preoperative IABP support, prolonged CPB time, low cardiac output and prolonged mechanical ventilation are the risk factors of abdominal complications. Conclusions Abdominal complications after cardiovascular surgery with CPB have a low incidence but a higher mortality. Early detection and prompt appropriate intervention are essential for the outcome of the patients.

  5. Transverse abdominal plane neurostimulation for chronic abdominal pain: a novel technique.

    Science.gov (United States)

    Gupta, Mayank; Goodson, Robert

    2014-01-01

    Management of chronic abdominal pain can be challenging. Sometimes patients fail to get adequate response from multiple medications and nerve blocks. We present a patient case report of chronic abdominal pain with a history of multiple surgeries managed successfully by neuromodulation of the transverse abdominis plane (TAP). The TAP block is a procedure in which local anesthetic is injected into the abdominal fascial plane that carries sensory nerves to the abdominal wall in order to block pain sensation. It has been shown to reduce postoperative pain and analgesic dependence after abdominal and gynecological surgeries. A 60-year-old woman presented to us for chronic abdominal pain for which medications provided little relief. She had an extensive history of abdominal surgeries and was also treated for lower back pain with surgery and less invasive procedures in the past. Under our care, she underwent 2 TAP blocks with almost complete resolution of her abdominal pain. Her pain, however, came back within a few of weeks of the procedures. Since our patient found pain relief from the TAP blocks, we proceeded with neurostimulation of the TAP for long-term pain relief. We placed a dorsal column stimulator 16 contact lead for lower back and leg pain and 8 contact leads placed in the TAP under ultrasound guidance. She has had multiple follow-ups since her TAP lead placement procedure with continued and near complete resolution of her abdominal pain. The TAP lead stimulation was helping her abdominal pain and the dorsal column lead stimulation was helping her back and leg pain.

  6. Effects of acupuncture therapy on abdominal fat and hepatic fat content in obese children: a magnetic resonance imaging and proton magnetic resonance spectroscopy study.

    Science.gov (United States)

    Zhang, Hong; Peng, Yun; Liu, ZuXiang; Li, Shilian; Lv, Zhongli; Tian, LiFang; Zhu, Jie; Zhao, XuNa; Chen, Min

    2011-05-01

    The aim of this study was to use magnetic resonance imaging (MRI) together with proton magnetic resonance spectroscopy ((1)H-MRS) to study the influence of acupuncture therapy on abdominal fat and hepatic fat content in obese children. The design was a longitudinal, clinical intervention study of acupuncture therapy. SUBJECTS were 10 healthy, obese children (age: 11.4 ± 1.65 years, body-mass index [BMI]: 29.03 ± 4.81 kg/m(2)). Measurements included various anthropometric parameters, abdominal fat (assessed by MRI) and hepatic fat content (assessed by (1)H-MRS) at baseline and after 1 month of acupuncture therapy. One (1) month of acupuncture therapy significantly reduced the subjects' BMI by 3.5% (p = 0.005), abdominal visceral adipose tissue (VAT) volume by 16.04% (p  0.05). There was a significant correlation between the level of abdominal fat (SAT, VAT) and anthropometric parameters (weight, BMI, waist circumferences, hip circumferences). There was no statistically significant correlation between IHTG and anthropometric parameters or abdominal fat content. The first direct experimental evidence is provided demonstrating that acupuncture therapy significantly reduces BMI and abdominal adipose tissue by reducing abdominal VAT content without significant changes in body weight, waist circumference, hip circumference, WHR, abdominal SAT, or IHTG content. Thus, the use of acupuncture therapy to selectively target a reduction in abdominal VAT content should become more important and more popular in the future.

  7. Intra-Abdominal Hypertension and Abdominal Compartment Syndrome in Association with Ruptured Abdominal Aortic Aneurysm in the Endovascular Era: Vigilance Remains Critical

    Directory of Open Access Journals (Sweden)

    Matthew C. Bozeman

    2012-01-01

    In this review, we describe published experience with IAH and ACS complicating abdominal vascular catastrophes, experience with ACS complicating endovascular repair of rAAAs, and techniques for management of the abdominal wound. Vigilance and appropriate management of IAH and ACS remains critically important in decreasing morbidity and optimizing survival following catastrophic intra-abdominal vascular events.

  8. Robust design of multiple-input multiple-output radar waveform covariance matrix in the presence of clutter

    Science.gov (United States)

    Guo, Rongyan; Wang, Hongyan

    2016-07-01

    In this work, the issue of robust waveform optimization is addressed in the presence of clutter to improve the worst-case estimation accuracy for collocated multiple-input multiple-output (MIMO) radar. Robust design is necessary due to the fact that waveform design may be sensitive to uncertainties in the initial parameter estimates. Following the min-max approach, the robust waveform covariance matrix design is formulated here on the basis of Cramér-Rao Bound to ease this sensitivity systematically for improving the worst-case accuracy. To tackle the resultant complicated and nonlinear problem, a new diagonal loading (DL)-based iterative approach is developed, in which the inner optimization problem can first be decomposed to some independent subproblems by using the Hadamard's inequality, and then these subproblems can be reformulated into convex issues by using DL method, as well as the outer optimization problem can also be relaxed to a convex issue by translating the nonlinear function into a linear one, and, hence, both of them can be solved very effectively. An optimal solution to the original problem can be obtained via the least-squares fitting of the solution acquired by the iterative approach. Numerical simulations show the efficiency of the proposed method.

  9. The Microcirculation System in Critical Conditions Caused by Abdominal Sepsis

    Directory of Open Access Journals (Sweden)

    S. L. Kan

    2011-01-01

    Full Text Available Objective: to evaluate the microcirculation system in critical conditions caused by abdominal sepsis for a further differentiated approach to intensive care. Subjects and methods. Twenty-four patients with abdominal sepsis (mean age 42.9±0.9 years were examined; a control group consisted of 35 apparently healthy individuals (mean age 40.1±2.1 years. Over 11 days, the microcirculatory bed was evaluated by cutaneous laser Doppler flowmetry by means of a ЛАКК-02 laser capillary blood flow analyzer made in the Russian Federation (LAZMA Research-and-Production Association, by using a basic light guide for percutaneous microcirculation studies. Results. Throughout the study, tissue blood perfusion remained in the patients with sepsis due to the higher effect of mainly active components of vascular tone regulation on the microvascular bed. In a poor outcome, there was a reduction in both active and passive regulatory effects on tissue perfusion chiefly due to local (myogenic factors. Conclusion. The findings suggest that the patients with sepsis have microcirculatory regulation changes aimed at maintaining tissue perfusion. A follow-up of the microcirculation may be useful in choosing intensive care tactics and predicting disease outcome. Key words: sepsis, microcirculation, microvascular bed, micro blood flow, tissue perfusion.

  10. Abdominal Wall Desmoid during Pregnancy: Diagnostic Challenges

    Directory of Open Access Journals (Sweden)

    Johnny Awwad

    2013-01-01

    Full Text Available Background. Desmoids are benign tumors, with local invasive features and no metastatic potential, which have rarely been described to be pregnancy associated. Case. We described the rapid growth of an anterior abdominal wall mass in a 40-year-old pregnant woman. Due to its close proximity to the enlarged uterus, it was misdiagnosed to be a uterine leiomyoma by ultrasound examination. Final tissue diagnosis and radical resection were done at the time of abdominal delivery. Conclusion. Due to the diagnostic limitations of imaging techniques, desmoids should always be considered when the following manifestations are observed in combination: progressive growth of a solitary abdominal wall mass during pregnancy and well-delineated smooth tumor margins demonstrated by imaging techniques. This case emphasizes the importance of entertaining uncommon medical conditions in the differential diagnosis of seemingly common clinical manifestations.

  11. Electromyographic analysis of four popular abdominal exercises.

    Science.gov (United States)

    Piering, A W; Janowski, A P; Wehrenberg, W B; Moore, M T; Snyder, A C

    1993-01-01

    This study was designed to evaluate the effects of four specific sit-up exercises on muscular activity of the rectus abdominis. Pairs of surface electrodes were placed unilaterally on four quadrants of the rectus abdominis, delimited by tendinous inscriptions, in four male subjects. Electromyographic (EMG) recordings were taken while the subjects performed four different abdominal exercises. Each abdominal exercise was hypothesized to have a specific effect on one of the four quadrants of the rectus abdominis. The four exercises analyzed were: 1) long lying crunch, 2) bent knee crunch, 3) leg raise, and 4) vertical leg crunch. Analysis of the standardized EMG recordings demonstrated no significant differences in the mean muscle activity between the four different quadrants, in the mean muscle activity between the four different exercises, and in interactions between the exercises and the quadrants of the rectus abdominis. We conclude that none of the four abdominal exercises studied are specific for strengthening individual muscle quadrants of the rectus abdominis.

  12. Abdominal wall hernias: imaging with spiral CT

    Energy Technology Data Exchange (ETDEWEB)

    Stabile Ianora, A.A.; Midiri, M.; Vinci, R.; Rotondo, A.; Angelelli, G. [Department of Radiology, Bari University Hospital (Italy)

    2000-06-01

    Computed tomography is an accurate method of identifying the various types of abdominal wall hernias, especially if they are clinically occult, and of distinguishing them from other diseases such as hematomas, abscesses and neoplasia. In this study we examined the CT images of 94 patients affected by abdominal wall hernias observed over a period of 6 years. Computed tomography clearly demonstrates the anatomical site of the hernial sac, the content and any occlusive bowel complications due to incarceration or strangulation. Clinical diagnosis of external hernias is particularly difficult in obese patients or in those with laparotic scars. In these cases abdominal imaging is essential for a correct preoperative diagnosis and to determine the most effective treatment. (orig.)

  13. Abdominal Wall Endometrioma. Report of Two Cases

    Directory of Open Access Journals (Sweden)

    Tahiluma Santana Pedraza

    2014-08-01

    Full Text Available Abdominal wall endometrioma is a condition rarely seen by surgeons. It represents a diagnostic challenge due to its similarity with other tumors. This entity occurs in fertile women and often appears two to five years after gynecological and obstetric surgical procedures. It must be considered when dealing with a cyclically painful nodule located in a laparotomy scar. The diagnosis is established by histological examination; most imaging tests determine the characteristics of the lesion, concomitant lesions and the intra-abdominal origin or location in the abdominal wall. The cases of two patients treated at the General Surgery Department of the María Eugenia González Comprehensive Diagnostic Center in the Capital District, Venezuela, are presented. Wide excision of the tissue and histological examination were performed, confirming the diagnosis. The postoperative course was uneventful. This case is presented given the rarity of this condition.

  14. Thoraco-abdominal coordination and performance during uphill running at altitude

    Science.gov (United States)

    Bernardi, Eva; Pratali, Lorenza; Mandolesi, Gaia; Spiridonova, Maria; Roi, Giulio Sergio; Cogo, Annalisa

    2017-01-01

    Introduction Running races on mountain trails at moderate-high altitude with large elevation changes throughout has become increasingly popular. During exercise at altitude, ventilatory demands increase due to the combined effects of exercise and hypoxia. Aim To investigate the relationships between thoraco-abdominal coordination, ventilatory pattern, oxygen saturation (SpO2), and endurance performance in runners during high-intensity uphill exercise. Methods Fifteen participants (13 males, mean age 42±9 yrs) ran a “Vertical Kilometer,” i.e., an uphill run involving a climb of approximately 1000 m with a slope greater than 30%. The athletes were equipped with a portable respiratory inductive plethysmography system, a finger pulse oximeter and a global positioning unit (GPS). The ventilatory pattern (ventilation (VE), tidal volume (VT), respiratory rate (RR), and VE/VT ratio), thoraco-abdominal coordination, which is represented by the phase angle (PhA), and SpO2 were evaluated at rest and during the run. Before and after the run, we assessed respiratory function, respiratory muscle strength and the occurrence of interstitial pulmonary edema by thoracic ultrasound. Results Two subjects were excluded from the respiratory inductive plethysmography analysis due to motion artifacts. A quadratic relationship between the slope and the PhA was observed (r = 0.995, p = 0.036). When the slope increased above 30%, the PhA increased, indicating a reduction in thoraco-abdominal coordination. The reduced thoraco-abdominal coordination was significantly related to reduced breathing efficiency (i.e., an increased VE/VT ratio; r = 0.961, p = 0.038) and SpO2 (r = -0.697, pabdominal coordination and consequent reduction in SpO2 were associated with interstitial pulmonary edema. Conclusion Reductions in thoraco-abdominal coordination are associated with a less efficient ventilatory pattern and lower SpO2 during uphill running. This fact could have a negative effect on performance

  15. Abdominal fat reducing outcome of exercise training: fat burning or hydrocarbon source redistribution?

    Science.gov (United States)

    Kuo, Chia-Hua; Harris, M Brennan

    2016-07-01

    Fat burning, defined by fatty acid oxidation into carbon dioxide, is the most described hypothesis to explain the actual abdominal fat reducing outcome of exercise training. This hypothesis is strengthened by evidence of increased whole-body lipolysis during exercise. As a result, aerobic training is widely recommended for obesity management. This intuition raises several paradoxes: first, both aerobic and resistance exercise training do not actually elevate 24 h fat oxidation, according to data from chamber-based indirect calorimetry. Second, anaerobic high-intensity intermittent training produces greater abdominal fat reduction than continuous aerobic training at similar amounts of energy expenditure. Third, significant body fat reduction in athletes occurs when oxygen supply decreases to inhibit fat burning during altitude-induced hypoxia exposure at the same training volume. Lack of oxygen increases post-meal blood distribution to human skeletal muscle, suggesting that shifting the postprandial hydrocarbons towards skeletal muscle away from adipose tissue might be more important than fat burning in decreasing abdominal fat. Creating a negative energy balance in fat cells due to competition of skeletal muscle for circulating hydrocarbon sources may be a better model to explain the abdominal fat reducing outcome of exercise than the fat-burning model.

  16. Decompressive laparotomy for abdominal compartment syndrome

    Science.gov (United States)

    Kimball, E.; Malbrain, M.; Nesbitt, I.; Cohen, J.; Kaloiani, V.; Ivatury, R.; Mone, M.; Debergh, D.; Björck, M.

    2016-01-01

    Background The effect of decompressive laparotomy on outcomes in patients with abdominal compartment syndrome has been poorly investigated. The aim of this prospective cohort study was to describe the effect of decompressive laparotomy for abdominal compartment syndrome on organ function and outcomes. Methods This was a prospective cohort study in adult patients who underwent decompressive laparotomy for abdominal compartment syndrome. The primary endpoints were 28‐day and 1‐year all‐cause mortality. Changes in intra‐abdominal pressure (IAP) and organ function, and laparotomy‐related morbidity were secondary endpoints. Results Thirty‐three patients were included in the study (20 men). Twenty‐seven patients were surgical admissions treated for abdominal conditions. The median (i.q.r.) Acute Physiology And Chronic Health Evaluation (APACHE) II score was 26 (20–32). Median IAP was 23 (21–27) mmHg before decompressive laparotomy, decreasing to 12 (9–15), 13 (8–17), 12 (9–15) and 12 (9–14) mmHg after 2, 6, 24 and 72 h. Decompressive laparotomy significantly improved oxygenation and urinary output. Survivors showed improvement in organ function scores, but non‐survivors did not. Fourteen complications related to the procedure developed in eight of the 33 patients. The abdomen could be closed primarily in 18 patients. The overall 28‐day mortality rate was 36 per cent (12 of 33), which increased to 55 per cent (18 patients) at 1 year. Non‐survivors were no different from survivors, except that they tended to be older and on mechanical ventilation. Conclusion Decompressive laparotomy reduced IAP and had an immediate effect on organ function. It should be considered in patients with abdominal compartment syndrome. PMID:26891380

  17. ABDOMINAL SCAR ENDOMETRIOSIS: REPORT OF 28 CASES

    Institute of Scientific and Technical Information of China (English)

    向阳; 郎景和; 王友芳; 黄荣丽; 连丽娟

    1995-01-01

    Twenty-eight cases of abdominal scar endometriosis from Janurary,1989 to December,1993 are reported.Of these patients,twenty-four underwent term cesarean section,and four underwent a midtrimester abortion by abdominal hysterotomy.The majority of patients manifested symptoms 1 year after the operation.The most common was a painful mass of scar tissue that became swollen and tender during menstruation.The pathogenesis,diagnosis and treatment are discussed.In correlation with the pathological findings,the effects of drug therapy are evaluated.It was found that surgical excision is the best method of treatment.

  18. Giant cystic abdominal masses in children

    Energy Technology Data Exchange (ETDEWEB)

    Wootton-Gorges, Sandra L.; Thomas, Kristen B.; Harned, Roger K.; Wu, Sarah R.; Stein-Wexler, Rebecca; Strain, John D. [University of California, Davis Health Center, Sacramento, CA (United States); Davis Children' s Hospital, Department of Radiology, Sacramento, CA (United States)

    2005-12-01

    In this pictorial essay the common and uncommon causes of large cystic and cyst-like abdominal masses in children are reviewed. We discuss and illustrate the following: mesenchymal hamartoma, choledochal cyst, hydrops of the gallbladder, congenital splenic cyst, pancreatic pseudocyst, pancreatic cystadenoma, hydronephrosis, multicystic dysplastic kidney, multilocular cystic nephroma, adrenal hemorrhage, mesenteric and omental cysts, gastrointestinal duplication cyst, meconium pseudocyst, ovarian cysts and cystic neoplasms, hematocolpos, urachal cysts, appendiceal abscess, abdominal and sacrococcygeal teratoma, and CSF pseudocyst. We also describe imaging features and clues to the diagnosis. (orig.)

  19. Penetrating abdominal injuries in children in Nigeria.

    Science.gov (United States)

    Ameh, E A; Nmadu, P T

    1999-09-01

    This is a report of a retrospective study of 24 children managed for penetrating abdominal injury over 10 years, and it represents 34% of all abdominal injuries in children in that period. Falls onto sharp objects within and around the home were responsible for ten of the injuries, seven were injured by animal horns and four were sporting injuries. Violence and road traffic accidents were uncommon. Most patients (67%) had evisceration of omentum or intestine, and one of these was found at laparotomy to have a jejuno-jejunal intussusception. Seven children had injury to hollow viscera. There were three deaths, one each from overwhelming sepsis, tetanus and haemorrhage.

  20. Systemic lupus erythematosus : abdominal radiologic findings

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Jae Cheon; Cho, On Koo; Lee, Yong Joo; Bae, Jae Ik; Kim, Yong Soo; Rhim, Hyun Chul; Ko, Byung Hee [Hanyang Univ. College of Medicine, Seoul (Korea, Republic of)

    1999-06-01

    Systemic lupus erythematosus(SLE) is a systemic disease of unknown etiology. Its main pathology is vasculitis and serositis, due to deposition of the immune complex or antibodies. Most findings are nonspecific ; abdominal manifestations include enteritis, hepatomegaly, pancreatic enlargement, serositis, lymphadenopathy, splenomegaly, nephritis, interstitial cystitis, and thrombophlebitis. We described radiologic findings of various organ involvement of SLE; digestive system, serosa, reticuloendothelial system, urinary system, and venous system. Diagnosis of SLE was done according to the criteria of American Rheumatism Association. Understanding of the variable imaging findings in SLE may be helpful for the early detection of abdominal involvement and complications.

  1. Laparoscopic surgery in children: abdominal wall complications

    Directory of Open Access Journals (Sweden)

    Vaccaro S.

    2017-06-01

    Full Text Available Minimal invasive surgery has become the standard of care for operations involving the thoracic and abdominal cavities for all ages. Laparoscopic complications can occur as well as more invasive surgical procedures and we can classify them into non-specific and specific. Our goal is to analyze the most influential available scientific literature and to expose important and recognized advices in order to reduce these complications. We examined the mechanism, risk factors, treatment and tried to outline how to prevent two major abdominal wall complications related to laparoscopy: bleeding and port site herniation .

  2. Bats coordinate sonar and flight behavior as they forage in open and cluttered environments

    DEFF Research Database (Denmark)

    Falk, Benjamin; Jakobsen, Lasse; Surlykke, Annemarie;

    2014-01-01

    . In this study, we examined the relationship between active sonar sampling and flight motor output as bats changed environments from open space to an artificial forest in a laboratory flight room. Using high-speed video and audio recordings, we reconstructed and analyzed 3D flight trajectories, sonar beam aim...... and acoustic sonar emission patterns as the bats captured prey. We found that big brown bats adjusted their sonar call structure, temporal patterning and flight speed in response to environmental change. The sonar beam aim of the bats predicted the flight turn rate in both the open room and the forest. However......, the relationship between sonar beam aim and turn rate changed in the forest during the final stage of prey pursuit, during which the bat made shallower turns. We found flight stereotypy developed over multiple days in the forest, but did not find evidence for a reduction in active sonar sampling with experience...

  3. Whether superficial abdominal reflex is affected by subcostal transverse abdominal incisions? A prospective, observational early experience

    Directory of Open Access Journals (Sweden)

    Jitin Bajaj

    2017-01-01

    Full Text Available Introduction: Superficial abdominal reflex (SAR is an important part of the neurologic assessment. It is normally present and may be present or absent in various physiological as well as pathological conditions. The presence of an abdominal incision creates a dilemma in the mind of the clinician for it affecting this reflex. As there is no literature on this, we decided to study the effect of abdominal incisions on SAR. Materials and Methods: It was a prospective, observational study. We evaluated the patients requiring transverse subcostal incision (range 3–12 cm both preoperatively and postoperatively, for their abdominal reflexes. Patients with preoperative normal and symmetrical abdominal reflexes were included in the study. Postoperatively, we compared the change of SAR with the preoperative status and analyzed the data. Results: A total of 94 patients underwent surgeries, out of which 54 patients came under inclusion criteria, comprising 36 males and 18 females. Subcostal transverse abdominal incisions were made for surgeries including both gastrointestinal and ventriculoperitoneal shunts. SAR was found unaffected by the incisions in all patients. Conclusions: Although the study was small, subcostal transverse abdominal incisions were not found to affect SAR.

  4. "EFFECTIVENESS OF ABDOMINAL WALL ELEVATOR IN REDUCING INTRA-ABDOMINAL PRESSURE AND CO2 VOLUME DURING LAPAROSCOPIC CHOLECYSTECTOMY"

    Directory of Open Access Journals (Sweden)

    A. Yaghoobi Notash

    2004-06-01

    Full Text Available Since CO2 pneumoperitoneum is the dominant method of laparoscopic exposure due to facility and good view, its physiologic effects are most relevant to the surgeons. CO2 pneumoperitoneum may affects hemodynamics by increased intra-abdominal pressure (IAP and the physiologic effects of absorbed CO2. The adverse effects of both mechanisms relate directly to the duration of the pneumoperitoneum and the elevation of IAP. Gasless laparoscopy involves obtaining exposure for laparoscopy by placing an internal retracting device through a small incision and lifting the anterior abdominal wall. We designed and made a mechanical wall elevator and used it in 24 patients, compared with a control group (52 cases using a conventional laparoscopic cholecystectomy. A prospective trial was undertaken in Sina Hospital, Tehran University of Medical Sciences from 1998 to 2000. The patients were assigned randomly to two groups. There was a significant decrease in IAP and CO2 consumption in the group using mechanical wall elevator as compared to conventional laparoscopic cholecystectomy, (mean IAP of 3.5 mmHg compared to 11.4 mmHg in the control group, mean CO2 volume 17 liters compared to 73 liters in the control group. We recommend this semigasless method in laparoscopy due to safety in performance and significant reduction in IAP through the surgery. This method provides a satisfactory view and easy performance without any increase in time or complications. The hospital stay and costs did not increase.

  5. [Pathogenetic aspects of intra-abdominal hypertension in patients with abdominal sepsis].

    Science.gov (United States)

    Veliev, N A; Gasanova, D N

    2011-09-01

    The authors had offered the original estimated system with the points calculation, basing on analysis of the examination and treatment results in 150 patients, suffering abdominal sepsis. The system, alike others, includes not only determination of the inflammation factors and indices of endotoxicosis, but as well as those, concerning intraabdominal pressure, the anterior abdominal wall rigidity and the tissues elasticity. Among the important indices, needed to determine, were considered those, which categorize the syndrome of intraabdominal, intrathoracic and microregional hypertension as well as the mechanisms of endotoxicosis pathogenesis. The authors recommend to use the indices of pathological consequences of this two factors while doing assessment of the abdominal sepsis severity.

  6. Fever and abdominal tumoral masses

    Directory of Open Access Journals (Sweden)

    Augustin C. Dima

    2016-04-01

    Full Text Available 49 year-old man presented to our clinic for pain in the right hypochondrium, diarrhea, and fever. The clinical examination highlights a tumoral formation in the right side of the abdomen, with firm consistency, poorly defined margins, and present mobility in the deep structures. On biological exams, leukocytosis with neutrophilia, inflammatory syndrome, and hypoalbuminaemia were identified. The first computed tomography exam described parietal thickening of the ascending colon, with infiltrative aspect, and multiple local adenopathies, lomboaortic and interaortocave. Moreover, four nodular liver tumors, with hypodense image in native examination, were identified. The lab tests for infectious diseases were all inconclusives: three hemocultures, three stool samples, and three coproparasitological exams were all negatives. Interdisciplinary examinations, internal medicine and infectious diseases, sustained the diagnosis of colonic neoplasm with peritumoral abscess and liver pseudo-tumoral masses. The colonoscopy did not revealed any bowel lesions relevant for neoplasia. This result as well as the bio-clinical context imposed abstention from surgical intervention. Wide spectrum antibiotics and symptomatic treatment were initiated. But, ten days after hospitalization, the second computed tomography exam showed reduction of the ascending colon wall thickness associated with significant increases of the liver tumors is so revealed. The investigations for other possible etiologies were so continued.

  7. Bats coordinate sonar and flight behavior as they forage in open and cluttered environments.

    Science.gov (United States)

    Falk, Benjamin; Jakobsen, Lasse; Surlykke, Annemarie; Moss, Cynthia F

    2014-12-15

    Echolocating bats use active sensing as they emit sounds and listen to the returning echoes to probe their environment for navigation, obstacle avoidance and pursuit of prey. The sensing behavior of bats includes the planning of 3D spatial trajectory paths, which are guided by echo information. In this study, we examined the relationship between active sonar sampling and flight motor output as bats changed environments from open space to an artificial forest in a laboratory flight room. Using high-speed video and audio recordings, we reconstructed and analyzed 3D flight trajectories, sonar beam aim and acoustic sonar emission patterns as the bats captured prey. We found that big brown bats adjusted their sonar call structure, temporal patterning and flight speed in response to environmental change. The sonar beam aim of the bats predicted the flight turn rate in both the open room and the forest. However, the relationship between sonar beam aim and turn rate changed in the forest during the final stage of prey pursuit, during which the bat made shallower turns. We found flight stereotypy developed over multiple days in the forest, but did not find evidence for a reduction in active sonar sampling with experience. The temporal patterning of sonar sound groups was related to path planning around obstacles in the forest. Together, these results contribute to our understanding of how bats coordinate echolocation and flight behavior to represent and navigate their environment.

  8. Connective tissue alteration in abdominal wall hernia

    DEFF Research Database (Denmark)

    Henriksen, N A; Yadete, D H; Sørensen, Lars Tue

    2011-01-01

    The aetiology and pathogenesis of abdominal wall hernia formation is complex. Optimal treatment of hernias depends on a full understanding of the pathophysiological mechanisms involved in their formation. The aim of this study was to review the literature on specific collagen alterations in abdom...

  9. A diagnostic approach to abdominal tuberculosis

    Institute of Scientific and Technical Information of China (English)

    Eser Vardareli; Baybora Kircali

    2005-01-01

    @@ TO THE EDITOR We read with interest the article by Uzunkoy et al[1]. about diagnosis of abdominal tuberculosis. In this article authors concluded that PCR for mycobacterium tuberculosis complex is a noninvasive method which can provide the diagnosis in most cases. If this tests negative or not feasible, laparotomy should be performed.

  10. Unusual Differential Diagnosis of Upper Abdominal Pain

    Directory of Open Access Journals (Sweden)

    Lanthaler Monika

    2009-01-01

    The peculiarity of this case is the rarity of toothpick ingestion and gastric perforation in a young and healthy white Caucasian followed by development of a liver abscess after primary uneventful endoscopic removal. In light of this case, gastric perforation due to ingested foreign bodies such as toothpicks can be considered a rare cause of upper abdominal pain.

  11. The neonate with an abdominal mass.

    Science.gov (United States)

    Chandler, John C; Gauderer, Michael W L

    2004-08-01

    Abdominal masses in neonates reflect a wide spectrum of diseases,from lesions that can cause significant morbidity and mortality,to conditions readily corrected surgically, to entities which maybe safely observed. It is incumbent upon the infant's physician to determine the nature of the mass in a timely, safe, and cost-effective manner.

  12. [Intraabdominal hypertension and abdominal compartment syndrome

    DEFF Research Database (Denmark)

    Sonne, M.; Hilligsø, Jens Georg

    2008-01-01

    Intraabdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are rare conditions with high mortality. IAH is an intraabdominal pressure (IAP) above 12 mmHg and ACS an IAP above 20 mmHg with evidence of organ dysfunction. IAP is measured indirectly via the bladder or stomach. Various...

  13. [Albert Einstein and his abdominal aortic aneurysm].

    Science.gov (United States)

    Cervantes Castro, Jorge

    2011-01-01

    The interesting case of Albert Einstein's abdominal aortic aneurysm is presented. He was operated on at age 69 and, finding that the large aneurysm could not be removed, the surgeon elected to wrap it with cellophane to prevent its growth. However, seven years later the aneurysm ruptured and caused the death of the famous scientist.

  14. Postoperative pleural effusion following upper abdominal surgery

    DEFF Research Database (Denmark)

    Nielsen, P H; Jepsen, S B; Olsen, A D

    1989-01-01

    Of 128 patients who underwent upper abdominal surgery, examined by standard preoperative and postoperative chest roentgenograms for the formation of postoperative pleural effusions, 89 had postoperative pleural effusions. Their presence was not related to the type of operation, infection, serum a...

  15. [A young woman with acute abdominal pain

    NARCIS (Netherlands)

    Mooij, R.; Dillen, J. van

    2013-01-01

    A 17-year-old woman was operated in a Tanzanian hospital because of a suspected ruptured ectopic pregnancy. During laparatomy an interstitial ectopic pregnancy with an intact gestational sac was found. The ectopic pregnancy had ruptured into the abdominal cavity.

  16. Postoperative pleural effusion following upper abdominal surgery

    DEFF Research Database (Denmark)

    Nielsen, P H; Jepsen, S B; Olsen, A D

    1989-01-01

    Of 128 patients who underwent upper abdominal surgery, examined by standard preoperative and postoperative chest roentgenograms for the formation of postoperative pleural effusions, 89 had postoperative pleural effusions. Their presence was not related to the type of operation, infection, serum a...

  17. ADVANCED ABDOMINAL PREGNANCY: THREE CASES WITH A ...

    African Journals Online (AJOL)

    least 6 cm above the plane of the brim. The foetal .... history of abdominal pains, i.e. 'spurious labour' probably due to the ... a combination of several features; from a study of these, a high index of ... Foetal parts overlie the maternal spine in a lateral view. 4. ... provided the X-ray examination excludes foetal abnor- malities' ...

  18. Reconstruction of complex abdominal wall defects

    NARCIS (Netherlands)

    Slater, N.J.

    2014-01-01

    Incisional hernia is by far the most common complication after laparotomies, occurring in 10 – 20%. Its occurrence is secondary to insufficient healing of the postoperative scar, resulting in wound dehiscence and protrusion of abdominal contents through an opening in the musculo-fascial layer of the

  19. Genetics Home Reference: abdominal wall defect

    Science.gov (United States)

    ... Aug;6(4):232-6. Citation on PubMed Islam S. Clinical care outcomes in abdominal wall defects. Curr ... Site Map Customer Support Selection Criteria for Links USA.gov Copyright Privacy Accessibility FOIA Viewers & Players U.S. ...

  20. Abdominal muscle function and incisional hernia

    DEFF Research Database (Denmark)

    Jensen, K K; Kjaer, M; Jorgensen, L N

    2014-01-01

    of life depends largely on abdominal muscle function (AMF), and the present review thus evaluates to what extent AMF is influenced by VIH and surgical repair. METHODS: The PubMed and EMBASE databases were searched for articles following a systematic strategy for inclusion. RESULTS: A total of seven...