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Sample records for scintigraphically estimated extent

  1. Dynamic renal scintigraphic estimation of deceased donor kidneys in a rat model

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    Huseyin Aydin Mitil

    2017-01-01

    Full Text Available At present a large number of the renal transplantations are being performed from the deceased donors. The success of these transplantations depends on the viability of the deceased donor kidneys. The aim of this study was to investigate the reliability of scintigraphic estimation of function of deceased donor kidneys by comparing the histopathologic and scintigraphic findings. Ten rats were included in the study (2–3 months old, 250–300 g, all male. Control scintigraphy was performed to all the rats by injection of 37 MBq Tc-99m DTPA from the tail vein in a dynamic manner. Brain death of the rats was achieved by inflation of a Fogartys catheter in the cranial cavity. Immediately, after brain death confirmation, dynamic renal scintigraphy was performed with the same parameters of control scintigraphy. In the comparison of scintigraphies obtained in the before and just after brain death period, there was impairment of tubular functions, concentration and excretion functions in the postbrain death period. In the immediate postbrain death period, there was a significant elevation in the glomerular filtration rate and time to maximum concentration values. In the histopathological evaluation of the kidney samples in the postbrain death period, there were definitive findings of tubular impairment. Dynamic renal scintigraphy also demonstrated definite impairment of tubular system and tubular functions in the deceased donor kidneys. This could explain the reason of the increased frequency of acute tubular necrosis seen among deceased donor kidneys.

  2. Scintigraphic supervision of osteitis

    International Nuclear Information System (INIS)

    Manigault, L.; Sureau, B.; Wioland, M.; Perez, R.

    1975-01-01

    On the assumption that isotopic examinations of the bone metabolism and especially the scintigraphic method could give valuable results in the observation of osteitis patients treated with antibiotics, four cases of this disease were selected and followed regularly every three or four months for at least a year. Several bone scintigraphs were carried out with a scintillation camera after intraveinous injection of technetium-labelled pyrophosphate and the hyperfixation variations of the osteitis centre are given as a function of time. It is shown that bone scintigraphy gives an exact picture of the dimensions and morphology of lesions caused by an osteitis centre and above all, if repeated, enables the development of the infected region to be estimated. It seems that the healing of osteitis can be judged from scintigraphic evidence. Scintigraphy may be considered as a means to check the efficiency of an antibiotic treatment [fr

  3. Rapid Estimates of Rupture Extent for Large Earthquakes Using Aftershocks

    Science.gov (United States)

    Polet, J.; Thio, H. K.; Kremer, M.

    2009-12-01

    The spatial distribution of aftershocks is closely linked to the rupture extent of the mainshock that preceded them and a rapid analysis of aftershock patterns therefore has potential for use in near real-time estimates of earthquake impact. The correlation between aftershocks and slip distribution has frequently been used to estimate the fault dimensions of large historic earthquakes for which no, or insufficient, waveform data is available. With the advent of earthquake inversions that use seismic waveforms and geodetic data to constrain the slip distribution, the study of aftershocks has recently been largely focused on enhancing our understanding of the underlying mechanisms in a broader earthquake mechanics/dynamics framework. However, in a near real-time earthquake monitoring environment, in which aftershocks of large earthquakes are routinely detected and located, these data may also be effective in determining a fast estimate of the mainshock rupture area, which would aid in the rapid assessment of the impact of the earthquake. We have analyzed a considerable number of large recent earthquakes and their aftershock sequences and have developed an effective algorithm that determines the rupture extent of a mainshock from its aftershock distribution, in a fully automatic manner. The algorithm automatically removes outliers by spatial binning, and subsequently determines the best fitting “strike” of the rupture and its length by projecting the aftershock epicenters onto a set of lines that cross the mainshock epicenter with incremental azimuths. For strike-slip or large dip-slip events, for which the surface projection of the rupture is recti-linear, the calculated strike correlates well with the strike of the fault and the corresponding length, determined from the distribution of aftershocks projected onto the line, agrees well with the rupture length. In the case of a smaller dip-slip rupture with an aspect ratio closer to 1, the procedure gives a measure

  4. Estimation of steam-chamber extent using 4D seismic

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, M. [Waseda Univ., Waseda (Japan); Endo, K. [Japan Canada Oil Sands Ltd., Calgary, AB (Canada); Onozuka, S. [Japan Oil, Gas and Metals National Corp., Tokyo (Japan)

    2009-07-01

    The steam-assisted gravity drainage (SAGD) technique is among the most effective steam injection methods and is widely applied in Canadian oil-sand reservoirs. The SAGD technology uses hot steam to decrease bitumen viscosity and allow it to flow. Japan Canada Oil Sands Limited (JACOS) has been developing an oil-sand reservoir in the Alberta's Hangingstone area since 1997. This paper focused on the western area of the reservoir and reported on a study that estimated the steam-chamber extent generated by horizontal well pairs. It listed steam injection start time for each well of the western area. Steam-chamber distribution was determined by distinguishing high temperature and high pore-pressure zones from low temperature and high pore-pressure zones. The bitumen recovery volume in the steam-chamber zone was estimated and compared with the actual cumulative production. This paper provided details of the methodology and interpretation procedures for the quantitative method to interpret 4D-seismic data for a SAGD process. A procedure to apply a petrophysical model was demonstrated first by scaling laboratory measurements to field-scale applications, and then by decoupling pressure and temperature effects. The first 3D seismic data in this study were already affected by higher pressures and temperatures. 11 refs., 3 tabs., 12 figs.

  5. Scintigraphic estimation of the duodeno-gastric reflux in the unclerous disease

    International Nuclear Information System (INIS)

    Kopanski, Z.; Cienciala, A.; Micherdzinski, J.; Brandys, J.; Zastepa, P.; Witkowska, B.

    1993-01-01

    The analysis includes 58 patients with an ulcer in the duodenum, 40 patients with an ulcer in the stomach, and 13 persons making up the control group. In all patients submitted to the ratio-isotopic estimation of the duodeno-gastric reflux as well as to the chromatographic determination of the concentration of bile acids and lysolecithin in the gastric juice, an almost identically frequent occurrence of the reflux of the duodeno gastric contents into the ulcer of the stomach and of the duodenum was confirmed. It was shown that half of the ulcers of the stomach originate without the participation of the duodeno gastric reflux. It was also established that the average total concentrations of bile acids and lysolecithin are very high in the gastric juice, and in some even statistically significant cases, in the ulcer of the stomach in comparison with the remaining analysed groups of patients. (author). 17 refs, 4 figs

  6. Possible role of the scintigraphic estimation of the relative liver perfusion in the choice of treatment of liver carcinomas

    International Nuclear Information System (INIS)

    Artiko, V.; Obradovic, V.; Davidovic, B.; Petrovic, N.; Vlajkoviae, M.; Kostic, K.

    2005-01-01

    Full text: In the pre-evaluation and diagnosis of the patients with liver tumors, significant nuclear medicine methods used are: radiocolloid, blood pool, hepatobiliary scintigraphy, angioscintigraphy with radiolabeled microspheres as well as 'first pass' radionuclide angiography, which can precede all of the above mentioned methods, during single injection application. The aim of the study is evaluation of the possible role of the scintigraphic estimation of the relative liver perfusion in the choice of treatment of liver carcinomas. The study was performed in 120 patients: 24 controls (C), 35 with benign liver tumors (BT), 35 with hepatocellular carcinomas (HCC), 19 with metastases of colorectal carcinomas (MCC) as well as 7 with metastases of other tumors (MOT-bronchus, lung carcinoma and lymphoma). 7/35 HCC had cavernous portal vein developed after tumor thrombosis, 2 had complete thrombosis and 5 had incomplete thrombosis (thrombosis of the either of portal venous branches (3) and incomplete portal venous thrombosis -2). 2/19 patients with MCC had cavernous portal vein developed after tumor thrombosis, 3 had complete portal venous occlusion and 4 incomplete thrombosis (thrombosis of the either of branches). The study was performed with ROTA scintillation camera and Micro Delta computer, during 60 sec (1f/sec) from i.v.application of 740 MBq 99mTc-pertecnetate. TA curves were generated using liver ROI, spleen ROI and left kidney ROI, and curves were generated. Hepatic perfusion index was calculated using slope analysis (Portal slope Ps and arterial slope As) method according to following formula HPI=Ps/(Ps+As). Complementary methods used were Doppler ultrasonography, CT, MRI, tumor marker assays (CEA, Ca19-9, AFP) laboratory analyses, pathohistological finding and clinical diagnosis. In C, HPI was 0.68±0.06 which did not differ from the value in BT (0.64 ±0.08) (p>0.05). However, in HCC ( X=0.26±0.20), and LM (X=0.40±0.28), HPI values were significantly

  7. Estimating Global Cropland Extent with Multi-year MODIS Data

    Directory of Open Access Journals (Sweden)

    Christopher O. Justice

    2010-07-01

    Full Text Available This study examines the suitability of 250 m MODIS (MODerate Resolution Imaging Spectroradiometer data for mapping global cropland extent. A set of 39 multi-year MODIS metrics incorporating four MODIS land bands, NDVI (Normalized Difference Vegetation Index and thermal data was employed to depict cropland phenology over the study period. Sub-pixel training datasets were used to generate a set of global classification tree models using a bagging methodology, resulting in a global per-pixel cropland probability layer. This product was subsequently thresholded to create a discrete cropland/non-cropland indicator map using data from the USDA-FAS (Foreign Agricultural Service Production, Supply and Distribution (PSD database describing per-country acreage of production field crops. Five global land cover products, four of which attempted to map croplands in the context of multiclass land cover classifications, were subsequently used to perform regional evaluations of the global MODIS cropland extent map. The global probability layer was further examined with reference to four principle global food crops: corn, soybeans, wheat and rice. Overall results indicate that the MODIS layer best depicts regions of intensive broadleaf crop production (corn and soybean, both in correspondence with existing maps and in associated high probability matching thresholds. Probability thresholds for wheat-growing regions were lower, while areas of rice production had the lowest associated confidence. Regions absent of agricultural intensification, such as Africa, are poorly characterized regardless of crop type. The results reflect the value of MODIS as a generic global cropland indicator for intensive agriculture production regions, but with little sensitivity in areas of low agricultural intensification. Variability in mapping accuracies between areas dominated by different crop types also points to the desirability of a crop-specific approach rather than attempting

  8. Estimated impact of global population growth on future wilderness extent

    Science.gov (United States)

    Dumont, E.

    2012-06-01

    Wilderness areas in the world are threatened by the environmental impacts of the growing global human population. This study estimates the impact of birth rate on the future surface area of biodiverse wilderness and on the proportion of this area without major extinctions. The following four drivers are considered: human population growth (1), agricultural efficiency (2), groundwater drawdown by irrigation (3), and non-agricultural space used by humans (buildings, gardens, roads, etc.) (4). This study indicates that the surface area of biodiverse unmanaged land will reduce with about 5.4% between 2012 and 2050. Further, it indicates that the biodiverse land without major extinctions will reduce with about 10.5%. These percentages are based on a commonly used population trajectory which assumes that birth rates across the globe will reduce in a similar way as has occurred in the past in many developed countries. Future birth rate is however very uncertain. Plausible future birth rates lower than the expected rates lead to much smaller reductions in surface area of biodiverse unmanaged land (0.7% as opposed to 5.4%), and a reduction in the biodiverse land without major extinctions of about 5.6% (as opposed to 10.5%). This indicates that birth rate is an important factor influencing the quality and quantity of wilderness remaining in the future.

  9. Scintigraphic demonstration of splenosis

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, C.A.; Sakimura, I.T.; Siegel, M.E.

    1986-03-01

    A case of splenosis, or the autotransplantation of splenic tissue following trauma, was encountered unexpectedly on a routine liver scan performed in the workup of alcoholic liver disease. Confirmatory scintigraphic images using Tc-99m labeled, heat-damaged, autologous erythrocytes are presented with CT scans of the abdomen.

  10. Capturing heterogeneity: The role of a study area's extent for estimating mean throughfall

    Science.gov (United States)

    Zimmermann, Alexander; Voss, Sebastian; Metzger, Johanna Clara; Hildebrandt, Anke; Zimmermann, Beate

    2016-11-01

    The selection of an appropriate spatial extent of a sampling plot is one among several important decisions involved in planning a throughfall sampling scheme. In fact, the choice of the extent may determine whether or not a study can adequately characterize the hydrological fluxes of the studied ecosystem. Previous attempts to optimize throughfall sampling schemes focused on the selection of an appropriate sample size, support, and sampling design, while comparatively little attention has been given to the role of the extent. In this contribution, we investigated the influence of the extent on the representativeness of mean throughfall estimates for three forest ecosystems of varying stand structure. Our study is based on virtual sampling of simulated throughfall fields. We derived these fields from throughfall data sampled in a simply structured forest (young tropical forest) and two heterogeneous forests (old tropical forest, unmanaged mixed European beech forest). We then sampled the simulated throughfall fields with three common extents and various sample sizes for a range of events and for accumulated data. Our findings suggest that the size of the study area should be carefully adapted to the complexity of the system under study and to the required temporal resolution of the throughfall data (i.e. event-based versus accumulated). Generally, event-based sampling in complex structured forests (conditions that favor comparatively long autocorrelations in throughfall) requires the largest extents. For event-based sampling, the choice of an appropriate extent can be as important as using an adequate sample size.

  11. Flood extent and water level estimation from SAR using data-model integration

    Science.gov (United States)

    Ajadi, O. A.; Meyer, F. J.

    2017-12-01

    Synthetic Aperture Radar (SAR) images have long been recognized as a valuable data source for flood mapping. Compared to other sources, SAR's weather and illumination independence and large area coverage at high spatial resolution supports reliable, frequent, and detailed observations of developing flood events. Accordingly, SAR has the potential to greatly aid in the near real-time monitoring of natural hazards, such as flood detection, if combined with automated image processing. This research works towards increasing the reliability and temporal sampling of SAR-derived flood hazard information by integrating information from multiple SAR sensors and SAR modalities (images and Interferometric SAR (InSAR) coherence) and by combining SAR-derived change detection information with hydrologic and hydraulic flood forecast models. First, the combination of multi-temporal SAR intensity images and coherence information for generating flood extent maps is introduced. The application of least-squares estimation integrates flood information from multiple SAR sensors, thus increasing the temporal sampling. SAR-based flood extent information will be combined with a Digital Elevation Model (DEM) to reduce false alarms and to estimate water depth and flood volume. The SAR-based flood extent map is assimilated into the Hydrologic Engineering Center River Analysis System (Hec-RAS) model to aid in hydraulic model calibration. The developed technology is improving the accuracy of flood information by exploiting information from data and models. It also provides enhanced flood information to decision-makers supporting the response to flood extent and improving emergency relief efforts.

  12. Estimating the location and spatial extent of a covert anthrax release.

    Directory of Open Access Journals (Sweden)

    Judith Legrand

    2009-01-01

    Full Text Available Rapidly identifying the features of a covert release of an agent such as anthrax could help to inform the planning of public health mitigation strategies. Previous studies have sought to estimate the time and size of a bioterror attack based on the symptomatic onset dates of early cases. We extend the scope of these methods by proposing a method for characterizing the time, strength, and also the location of an aerosolized pathogen release. A back-calculation method is developed allowing the characterization of the release based on the data on the first few observed cases of the subsequent outbreak, meteorological data, population densities, and data on population travel patterns. We evaluate this method on small simulated anthrax outbreaks (about 25-35 cases and show that it could date and localize a release after a few cases have been observed, although misspecifications of the spore dispersion model, or the within-host dynamics model, on which the method relies can bias the estimates. Our method could also provide an estimate of the outbreak's geographical extent and, as a consequence, could help to identify populations at risk and, therefore, requiring prophylactic treatment. Our analysis demonstrates that while estimates based on the first ten or 15 observed cases were more accurate and less sensitive to model misspecifications than those based on five cases, overall mortality is minimized by targeting prophylactic treatment early on the basis of estimates made using data on the first five cases. The method we propose could provide early estimates of the time, strength, and location of an aerosolized anthrax release and the geographical extent of the subsequent outbreak. In addition, estimates of release features could be used to parameterize more detailed models allowing the simulation of control strategies and intervention logistics.

  13. A Streaming Algorithm for Online Estimation of Temporal and Spatial Extent of Delays

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    Kittipong Hiriotappa

    2017-01-01

    Full Text Available Knowing traffic congestion and its impact on travel time in advance is vital for proactive travel planning as well as advanced traffic management. This paper proposes a streaming algorithm to estimate temporal and spatial extent of delays online which can be deployed with roadside sensors. First, the proposed algorithm uses streaming input from individual sensors to detect a deviation from normal traffic patterns, referred to as anomalies, which is used as an early indication of delay occurrence. Then, a group of consecutive sensors that detect anomalies are used to temporally and spatially estimate extent of delay associated with the detected anomalies. Performance evaluations are conducted using a real-world data set collected by roadside sensors in Bangkok, Thailand, and the NGSIM data set collected in California, USA. Using NGSIM data, it is shown qualitatively that the proposed algorithm can detect consecutive occurrences of shockwaves and estimate their associated delays. Then, using a data set from Thailand, it is shown quantitatively that the proposed algorithm can detect and estimate delays associated with both recurring congestion and incident-induced nonrecurring congestion. The proposed algorithm also outperforms the previously proposed streaming algorithm.

  14. Combining measurements to estimate properties and characterization extent of complex biochemical mixtures; applications to Heparan Sulfate

    Science.gov (United States)

    Pradines, Joël R.; Beccati, Daniela; Lech, Miroslaw; Ozug, Jennifer; Farutin, Victor; Huang, Yongqing; Gunay, Nur Sibel; Capila, Ishan

    2016-04-01

    Complex mixtures of molecular species, such as glycoproteins and glycosaminoglycans, have important biological and therapeutic functions. Characterization of these mixtures with analytical chemistry measurements is an important step when developing generic drugs such as biosimilars. Recent developments have focused on analytical methods and statistical approaches to test similarity between mixtures. The question of how much uncertainty on mixture composition is reduced by combining several measurements still remains mostly unexplored. Mathematical frameworks to combine measurements, estimate mixture properties, and quantify remaining uncertainty, i.e. a characterization extent, are introduced here. Constrained optimization and mathematical modeling are applied to a set of twenty-three experimental measurements on heparan sulfate, a mixture of linear chains of disaccharides having different levels of sulfation. While this mixture has potentially over two million molecular species, mathematical modeling and the small set of measurements establish the existence of nonhomogeneity of sulfate level along chains and the presence of abundant sulfate repeats. Constrained optimization yields not only estimations of sulfate repeats and sulfate level at each position in the chains but also bounds on these levels, thereby estimating the extent of characterization of the sulfation pattern which is achieved by the set of measurements.

  15. Methods to estimate distribution and range extent of grizzly bears in the Greater Yellowstone Ecosystem

    Science.gov (United States)

    Haroldson, Mark A.; Schwartz, Charles C.; Thompson, Daniel J.; Bjornlie, Daniel D.; Gunther, Kerry A.; Cain, Steven L.; Tyers, Daniel B.; Frey, Kevin L.; Aber, Bryan C.

    2014-01-01

    The distribution of the Greater Yellowstone Ecosystem grizzly bear (Ursus arctos) population has expanded into areas unoccupied since the early 20th century. Up-to-date information on the area and extent of this distribution is crucial for federal, state, and tribal wildlife and land managers to make informed decisions regarding grizzly bear management. The most recent estimate of grizzly bear distribution (2004) utilized fixed-kernel density estimators to describe distribution. This method was complex and computationally time consuming and excluded observations of unmarked bears. Our objective was to develop a technique to estimate grizzly bear distribution that would allow for the use of all verified grizzly bear location data, as well as provide the simplicity to be updated more frequently. We placed all verified grizzly bear locations from all sources from 1990 to 2004 and 1990 to 2010 onto a 3-km × 3-km grid and used zonal analysis and ordinary kriging to develop a predicted surface of grizzly bear distribution. We compared the area and extent of the 2004 kriging surface with the previous 2004 effort and evaluated changes in grizzly bear distribution from 2004 to 2010. The 2004 kriging surface was 2.4% smaller than the previous fixed-kernel estimate, but more closely represented the data. Grizzly bear distribution increased 38.3% from 2004 to 2010, with most expansion in the northern and southern regions of the range. This technique can be used to provide a current estimate of grizzly bear distribution for management and conservation applications.

  16. Estimating the Spatial Extent of Unsaturated Zones in Heterogeneous River-Aquifer Systems

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    Schilling, Oliver S.; Irvine, Dylan J.; Hendricks Franssen, Harrie-Jan; Brunner, Philip

    2017-12-01

    The presence of unsaturated zones at the river-aquifer interface has large implications on numerous hydraulic and chemical processes. However, the hydrological and geological controls that influence the development of unsaturated zones have so far only been analyzed with simplified conceptualizations of flow processes, or homogeneous conceptualizations of the hydraulic conductivity in either the aquifer or the riverbed. We systematically investigated the influence of heterogeneous structures in both the riverbed and the aquifer on the development of unsaturated zones. A stochastic 1-D criterion that takes both riverbed and aquifer heterogeneity into account was developed using a Monte Carlo sampling technique. The approach allows the reliable estimation of the upper bound of the spatial extent of unsaturated areas underneath a riverbed. Through systematic numerical modeling experiments, we furthermore show that horizontal capillary forces can reduce the spatial extent of unsaturated zones under clogged areas. This analysis shows how the spatial structure of clogging layers and aquifers influence the propensity for unsaturated zones to develop: In riverbeds where clogged areas are made up of many small, spatially disconnected patches with a diameter in the order of 1 m, unsaturated areas are less likely to develop compared to riverbeds where large clogged areas exist adjacent to unclogged areas. A combination of the stochastic 1-D criterion with an analysis of the spatial structure of the clogging layers and the potential for resaturation can help develop an appropriate conceptual model and inform the choice of a suitable numerical simulator for river-aquifer systems.

  17. Scintigraphic assessment of colostomy irrigation.

    Science.gov (United States)

    Christensen, P.; Olsen, N.; Krogh, K.; Laurberg, S.

    2002-09-01

    OBJECTIVE: This study aims to evaluate colonic transport following colostomy irrigation with a new scintigraphic technique. MATERIALS AND METHODS: To label the bowel contents 19 patients (11 uncomplicated colostomy irrigation, 8 complicated colostomy irrigation) took 111In-labelled polystyrene pellets one and two days before investigation. 99mTc-DTPA was mixed with the irrigation fluid to assess its extent within the bowel. Scintigraphy was performed before and after a standardized washout procedure. The colon was divided into three segments 1: the caecum andascending colon; 2: the transverse colon; 3: the descending and sigmoid colon. Assuming ordered evacuation of the colon, the contribution of each colonic segment to the total evacuation was expressed as a percentage of the original segmental counts. These were added to reach a total defaecation score (range: 0-300). RESULTS: In uncomplicated colostomy irrigation, the median defaecation score was 235 (range: 145-289) corresponding to complete evacuation of the descending and transverse colon and 35% evacuation of the caecum/ascending colon. In complicated colostomy irrigation it was possible to distinguish specific emptying patterns. The retained irrigation fluid reached the caecum in all but one patient. CONCLUSION: Scintigraphy can be used to evaluate colonic emptying following colostomy irrigation.

  18. Impact of alternative metrics on estimates of extent of occurrence for extinction risk assessment.

    Science.gov (United States)

    Joppa, Lucas N; Butchart, Stuart H M; Hoffmann, Michael; Bachman, Steve P; Akçakaya, H Resit; Moat, Justin F; Böhm, Monika; Holland, Robert A; Newton, Adrian; Polidoro, Beth; Hughes, Adrian

    2016-04-01

    In International Union for Conservation of Nature (IUCN) Red List assessments, extent of occurrence (EOO) is a key measure of extinction risk. However, the way assessors estimate EOO from maps of species' distributions is inconsistent among assessments of different species and among major taxonomic groups. Assessors often estimate EOO from the area of mapped distribution, but these maps often exclude areas that are not habitat in idiosyncratic ways and are not created at the same spatial resolutions. We assessed the impact on extinction risk categories of applying different methods (minimum convex polygon, alpha hull) for estimating EOO for 21,763 species of mammals, birds, and amphibians. Overall, the percentage of threatened species requiring down listing to a lower category of threat (taking into account other Red List criteria under which they qualified) spanned 11-13% for all species combined (14-15% for mammals, 7-8% for birds, and 12-15% for amphibians). These down listings resulted from larger estimates of EOO and depended on the EOO calculation method. Using birds as an example, we found that 14% of threatened and near threatened species could require down listing based on the minimum convex polygon (MCP) approach, an approach that is now recommended by IUCN. Other metrics (such as alpha hull) had marginally smaller impacts. Our results suggest that uniformly applying the MCP approach may lead to a one-time down listing of hundreds of species but ultimately ensure consistency across assessments and realign the calculation of EOO with the theoretical basis on which the metric was founded. © 2015 Society for Conservation Biology.

  19. A curve fitting approach to estimate the extent of fermentation of indigestible carbohydrates

    NARCIS (Netherlands)

    Wang, H.; Weening, D.; Jonkers, E.; Boer, T.; Stellaard, F.; Small, A. C.; Preston, T.; Vonk, R. J.; Priebe, M. G.

    Background Information about the extent of carbohydrate digestion and fermentation is critical to our ability to explore the metabolic effects of carbohydrate fermentation in vivo. We used cooked (13)C-labelled barley kernels, which are rich in indigestible carbohydrates, to develop a method which

  20. Estimating the seaward extent of sea breeze from QuickSCAT scatterometry

    Digital Repository Service at National Institute of Oceanography (India)

    Aparna, M.; Shetye, S.R.; Shankar, D.; Shenoi, S.S.C.; Mehra, P.; Desai, R.G.P.

    An objective method for quantifying the seaward extent of the sea breeze is presented. The underlying assumption is that the offshore decay in the strength of the sea breeze results in an offshore decay of the vector correlation between the wind...

  1. A curve fitting approach to estimate the extent of fermentation of indigestible carbohydrates

    NARCIS (Netherlands)

    Wang, H.; Weening, D.; Jonkers, E.; Boer, T.; Stellaard, F.; Small, A. C.; Preston, T.; Vonk, R. J.; Priebe, M. G.

    2008-01-01

    Background Information about the extent of carbohydrate digestion and fermentation is critical to our ability to explore the metabolic effects of carbohydrate fermentation in vivo. We used cooked (13)C-labelled barley kernels, which are rich in indigestible carbohydrates, to develop a method which

  2. In vitro estimation of the rate and extent of ruminal digestion of cereal feed fraction

    DEFF Research Database (Denmark)

    Tahir, M.N.; Lund, Peter; Hetta, M.

    2011-01-01

    by their physical and chemical properties and might be ranked as highly and poorly degrading starch after their extent and rate of degradation in rumen (Nocek and Tamminga, 1991). It is hypothesized that rumen fermentation rate of cereal starch varies considerably and that this might affect fibre digestibility...

  3. GIS-based maps and area estimates of Northern Hemisphere permafrost extent during the Last Glacial Maximum

    NARCIS (Netherlands)

    Lindgren, A.; Hugelius, G.; Kuhry, P.; Christensen, T.R.; Vandenberghe, J.F.

    2016-01-01

    This study presents GIS-based estimates of permafrost extent in the northern circumpolar region during the Last Glacial Maximum (LGM), based on a review of previously published maps and compilations of field evidence in the form of ice-wedge pseudomorphs and relict sand wedges. We focus on field

  4. Detecting spatial structures in throughfall data: The effect of extent, sample size, sampling design, and variogram estimation method

    Science.gov (United States)

    Voss, Sebastian; Zimmermann, Beate; Zimmermann, Alexander

    2016-09-01

    In the last decades, an increasing number of studies analyzed spatial patterns in throughfall by means of variograms. The estimation of the variogram from sample data requires an appropriate sampling scheme: most importantly, a large sample and a layout of sampling locations that often has to serve both variogram estimation and geostatistical prediction. While some recommendations on these aspects exist, they focus on Gaussian data and high ratios of the variogram range to the extent of the study area. However, many hydrological data, and throughfall data in particular, do not follow a Gaussian distribution. In this study, we examined the effect of extent, sample size, sampling design, and calculation method on variogram estimation of throughfall data. For our investigation, we first generated non-Gaussian random fields based on throughfall data with large outliers. Subsequently, we sampled the fields with three extents (plots with edge lengths of 25 m, 50 m, and 100 m), four common sampling designs (two grid-based layouts, transect and random sampling) and five sample sizes (50, 100, 150, 200, 400). We then estimated the variogram parameters by method-of-moments (non-robust and robust estimators) and residual maximum likelihood. Our key findings are threefold. First, the choice of the extent has a substantial influence on the estimation of the variogram. A comparatively small ratio of the extent to the correlation length is beneficial for variogram estimation. Second, a combination of a minimum sample size of 150, a design that ensures the sampling of small distances and variogram estimation by residual maximum likelihood offers a good compromise between accuracy and efficiency. Third, studies relying on method-of-moments based variogram estimation may have to employ at least 200 sampling points for reliable variogram estimates. These suggested sample sizes exceed the number recommended by studies dealing with Gaussian data by up to 100 %. Given that most previous

  5. The deforestation debate; estimates vary widely over the extent of forest loss

    International Nuclear Information System (INIS)

    Monastersky, R.

    1993-01-01

    While tropical forests are vanishing at a disturbing rate, the wide-spread disagreement over deforestation estimates makes it difficult for government officials and scientists to assess the problem. In turn this hampers efforts to gauge the threat of related issues such as habitat destruction and global warming. Creating more confusion is the realization that partly deforested, but not stripped, lands have not been completely taken into account. In addition lands in tropical regions but outside the tropical rain forest are poorly represented. This article uses Brazil as an example of the conflicting estimates. The efforts of the United Nations Food and Agriculture Organization (FAO) to improve its estimates are described. An on-going NASA project to help is also described

  6. Can a sample of Landsat sensor scenes reliably estimate the global extent of tropical deforestation?

    Science.gov (United States)

    R. L. Czaplewski

    2003-01-01

    Tucker and Townshend (2000) conclude that wall-to-wall coverage is needed to avoid gross errors in estimations of deforestation rates' because tropical deforestation is concentrated along roads and rivers. They specifically question the reliability of the 10% sample of Landsat sensor scenes used in the global remote sensing survey conducted by the Food and...

  7. Estimating the environmental impact of home energy visits and extent of behaviour change

    International Nuclear Information System (INIS)

    Revell, Kristy

    2014-01-01

    The objective of this study was to estimate the environmental impact of a home energy visit programme, known as RE:NEW, that was delivered in London, in the United Kingdom. These home energy visits intended to encourage reductions in household carbon emissions and water consumption through the installation of small energy saving measures (such as radiator panels, in-home energy displays and low-flow shower heads), further significant energy saving measures (loft and cavity wall insulation) and behaviour change advice. The environmental impact of the programme was estimated in terms of carbon emissions abated and on average, for each household in the study, a visit led to an average carbon abatement of 146 kgCO 2 . The majority of this was achieved through the installation of small energy saving measures. The impact of the visits on the installation of significant measures was negligible, as was the impact on behaviour change. Therefore, these visits did not overcome the barriers required to generate behaviour change or the barriers to the installation of more significant energy saving measures. Given this, a number of recommendations are proposed in this paper, which could increase the efficacy of these home energy visits. - Highlights: • The environmental impact of the RE:NEW home energy visit programme is estimated. • Visits do not generate significant pro-environmental behaviour change. • Visits do not overcome the barriers to the installation loft and wall insulation. • Small energy saving measures yield carbon savings of 145 kgCO 2 /year. • The average carbon abatement per household was estimated to be 146 kgCO 2 /year

  8. Extent of emphysema estimated by the three dimensional CT (3D-CT) predicts pulmonary dysfunction in patients with COPD

    International Nuclear Information System (INIS)

    Fujita, Etsuo; Inoue, Yoshikazu; Tanaka Isao

    2003-01-01

    We assessed the extent of emphysematous area by the 3D-CT in 35 chronic stable patients (age 66.5±8.9 yrs). And we evaluated the data from the total lung volume estimated by the 3D-CT, % low attenuation area below -950 HU (%LAA) and pulmonary function tests (PFT). Total lung volume estimated by 3D-CT was correlated with total lung capacity (TLC) by PFT (r=0.736, p<0.0005). The % LAA correlated with forced expiratory volume (FEV) 1% (r=-0.716, p<0.001). We concluded that the 3D-CT is the excellent method of evaluating the extent of emphysema without effort. (author)

  9. The Effect of Finite Thickness Extent on Estimating Depth to Basement from Aeromagnetic Data

    Science.gov (United States)

    Blakely, R. J.; Salem, A.; Green, C. M.; Fairhead, D.; Ravat, D.

    2014-12-01

    Depth to basement estimation methods using various components of the spectral content of magnetic anomalies are in common use by geophysicists. Examples of these are the Tilt-Depth and SPI methods. These methods use simple models having the base of the magnetic body at infinity. Recent publications have shown that this 'infinite depth' assumption causes underestimation of the depth to the top of sources, especially in areas where the bottom of the magnetic layer is shallow, as would occur in high heat-flow regions. This error has been demonstrated in both model studies and using real data with seismic or well control. To overcome the limitation of infinite depth this contribution presents the mathematics for a finite depth contact body in the Tilt depth and SPI methods and applies it to the central Red Sea where the Curie isotherm and Moho are shallow. The difference in the depth estimation between the infinite and finite contacts is such a case is significant and can exceed 200%.

  10. Detecting Trends in Wetland Extent from MODIS Derived Soil Moisture Estimates

    Directory of Open Access Journals (Sweden)

    Thomas Gumbricht

    2018-04-01

    Full Text Available A soil wetness index for optical satellite images, the Transformed Wetness Index (TWI is defined and evaluated against ground sampled soil moisture. Conceptually, TWI is formulated as a non-linear normalized difference index from orthogonalized vectors representing soil and water conditions, with the vegetation signal removed. Compared to 745 ground sites with in situ measured soil moisture, TWI has a globally estimated Random Mean Square Error of 14.0 (v/v expressed as percentage, which reduces to 8.5 for unbiased data. The temporal variation in soil moisture is significantly captured at 4 out of 10 stations, but also fails for 2 to 3 out of 10 stations. TWI is biased by different soil mineral compositions, dense vegetation and shadows, with the latter two most likely also causing the failure of TWI to capture soil moisture dynamics. Compared to soil moisture products from microwave brightness temperature data, TWI performs slightly worse, but has the advantages of not requiring ancillary data, higher spatial resolution and a relatively simple application. TWI has been used for wetland and peatland mapping in previously published studies but is presented in detail in this article, and then applied for detecting changes in soil moisture for selected tropical regions between 2001 and 2016. Sites with significant changes are compared to a published map of global tropical wetlands and peatlands.

  11. Comparison of Scintigraphic and Radiological Results in the Diagnosis of Pancreatic Diseases

    Energy Technology Data Exchange (ETDEWEB)

    Deininger, H. K.; Sielaff, H. J. [Strahlenklinik der Staedt. Krankenanstalten Heilbronn, Heilbronn, Federal Republic of Germany (Germany)

    1969-05-15

    The results obtained by pancreas scanning and standard radiological diagnostic methods are compared. The roentgenographic examinations of the stomach, intestine, colon, biliary tract and kidneys were performed by standard X-ray methods and by abdominal tomography with pneumoretroperitoneum. Special methods of a radiological pancreatic diagnosis, e.g. selective angiography and intra-operative pancreatography, are intentionally not considered. So far 192 pancreas scans have been carried out after administration of {sup 75}Se-1 -selenomethionine. The patients were prepared either with a special diet or a fasting period. The quality of the pancreas scans depended on the functional state of the pancreatic tissue and a comparison with phantom studies allowed an approximate estimation of the extent of the parenchymatous lesions. Of the 87 cases with proven pancreatic diseases the results were compared with the scintigraphical and radiological findings. This comparative research illustrates the superiority of pancreas scanning over the conventional rontgenographic methods in the exclusion or detection of pancreatic diseases. (author)

  12. Scintigraphic appearances of Gaucher's disease

    International Nuclear Information System (INIS)

    Okada, Junichi; Uchiyama, Guio; Hayakawa, Kazushige; Araki, Tsutomu; Hayashi, Sanshin; Yamada, Kayoko; Seto, Kazuhiko

    1985-01-01

    Gaucher's disease is an inborn error of metabolism in which glucocerebroside accumlates within reticuloendotherial cells of spleen, liver and bone marrow. The scintigraphic appearances are described in a 19-year-old man with Gaucher's disease. The colloid scan showed increased uptake in the lung and bone marrow of legs where the reticuloendotherial system was activated. The bone scan demonstrated increased activity in the metaphyseal and diaphyseal region infiltrated by Gaucher's cell. Ga-67 was thought to be accumlated in the progressive focus of the disease. (author)

  13. Scintigraphic ventriculography and stress testing

    International Nuclear Information System (INIS)

    Goris, M.L.; Hung, J.; Debusk, R.F.

    1982-01-01

    Scintigraphic stress ventriculography yields information which is complex and defies description by the difference in ejection fraction between rest and maximum exercise only. The complexity results in part from the ''derived'' nature of the ejection fraction measurement, which is physiologically secondary to stroke volume and end-diastolic volume. Furthermore, the nature of the stress test in which the pulse (stress) is not independent from the response forces an analysis which considers ''when'' as much as ''what'' happens. Automation in data processing, however, has made oversimplification unnecessary and allows a more exhaustive but correct analysis

  14. Scintigraphic findings in ankylosing spondylitis

    International Nuclear Information System (INIS)

    Lentle, B.C.; Russell, A.S.; Percy, J.S.; Jackson, F.I.

    1977-01-01

    A prospective study of bone scintigraphic findings has been carried out in 63 patients, firmly diagnosed as having ankylosing spondylitis. In addition to abnormal uptake of the radiotracer at the sacroiliac joints, a peripheral arthropathy has been a common finding, particularly in the proximal joints, occurring in up to 50 percent of patients. Increased uptake of radiotracer in the spine has also been found both diffusely and focally. Focal increases have been noted at the apophyseal joints in 40 percent of patients and in three patients with a sterile intervertebral diskitis, an unusual complication of this disease only diagnosed in two patients after bone scintigraphy

  15. Scintigraphic findings in ankylosing spondylitis.

    Science.gov (United States)

    Lentle, B C; Russell, A S; Percy, J S; Jackson, F I

    1977-06-01

    A prospective study of bone scintigraphic findings has been carried out in 63 patients, firmly diagnosed as having ankylosing spondylitis. In addition to abnormal uptake of the radiotracer at the sacroiliac joints, a peripheral arthropathy has been a common finding, particularly in the proximal joints, occurring in up to 50% of patients. Increased uptake of radiotracer in the spine has also been found both diffusely and focally. Focal increases have been noted at the apophyseal joints in 40% of patients and in three patients with a sterile intervertebral diskitis, an unusual complication of this disease only diagnosed in two patients after bone scintigraphy.

  16. Scintigraphic evaluation of brain death

    International Nuclear Information System (INIS)

    Park, C. H.; Bai, M. S.; Cho, K. K.; Kim, S. J.; Yoon, S. N.; Cho, C. W.

    1997-01-01

    A law recognizing brain death is a life saving legal measure in patients suffering from badly diseased organs such as kidney, liver, heart, and lung. Such law is being discussed for legalization at the Korean National Assembly. There are various criteria used for brain death in western world and brain scintiscan is one of them. However, the scintiscan is not considered in establishing brain death in the draft of the law. The purpose of this report is to spread this technique in nuclear medicine society as well as in other medical societies. We evaluated 7 patients with clinical suspicion of brain death by various causes. The patient's age ranged from 5 to 39 years. We used 5-20mCi 99m Tc-HMPAO (d.1-hexamethyl propylene amine oxime) or ECD (Ethyl Cysteinate Dimer), lipophilic agents that cross BBB (blood brain barrier). A dynamic study followed by static or SPECT (single photon emission tomography) was performed. Interpretive criteria used for brain death were 1) no intracranial circulation 2) no brain uptake. The second criteria is heavily used. Five of 7 patients were scintigraphically brain dead and the remaining 2 had some brain uptake excluding the diagnosis of scintigraphic brain death. In conclusion, cerebral perfusion study using a lipophilic brain tracer offers a noninvasive, rapid, easy, accurate and reliable mean in the diagnosis of brain death. We believe that this modality should be included in the criteria of brain death in the draft of the proposed Korean law

  17. Scintigraphic estimation of the duodeno-gastric reflux in the unclerous disease; Scyntygraficzna ocena refluksu dwunastniczo-zoladkowego w chorobie wrzodowej

    Energy Technology Data Exchange (ETDEWEB)

    Kopanski, Z.; Cienciala, A.; Micherdzinski, J. [Szpital Wojskowy, Cracow (Poland); Brandys, J. [Uniwersytet Jagiellonski, Cracow (Poland); Zastepa, P.; Witkowska, B.

    1993-12-31

    The analysis includes 58 patients with an ulcer in the duodenum, 40 patients with an ulcer in the stomach, and 13 persons making up the control group. In all patients submitted to the ratio-isotopic estimation of the duodeno-gastric reflux as well as to the chromatographic determination of the concentration of bile acids and lysolecithin in the gastric juice, an almost identically frequent occurrence of the reflux of the duodeno gastric contents into the ulcer of the stomach and of the duodenum was confirmed. It was shown that half of the ulcers of the stomach originate without the participation of the duodeno gastric reflux. It was also established that the average total concentrations of bile acids and lysolecithin are very high in the gastric juice, and in some even statistically significant cases, in the ulcer of the stomach in comparison with the remaining analysed groups of patients. (author). 17 refs, 4 figs.

  18. Scintigraphic evaluation of gastroesophageal reflux

    International Nuclear Information System (INIS)

    Malmud, L.S.; Fisher, R.S.

    1983-01-01

    When patients have symptomatic gastroesophageal reflux disease, their symptoms usually respond to conventional therapeutic measures. In some patients, however, the symptoms may persist despite the application of standard treatment regimens. It is in these instances that the clinician may employ extensive diagnostic tests to determine the cause of the patient's complaints. Because the introduction of gastroesophageal scintigraphy, a number of other techniques were employed to evaluate gastroesophageal reflux. These include barium esophagography, barium cineesophagography; endoscopy; esophageal mucosal biopsy; esophageal manometry; the acid-clearance test; and acid-reflux testing. Each of the nonscintigraphic techniques has a limitation either in its sensitivity or in the requirement for endogastric intubation. In addition, with the exception of the scintigraphic method, none of the tests permits quantitation of reflux

  19. Scintigraphic imaging of endocrine organs

    International Nuclear Information System (INIS)

    Gross, M.D.; Shapiro, B.; Thrall, J.H.; Freitas, J.E.; Beierwaltes, W.H.

    1984-01-01

    The nuclear medicine approach to the portrayal of endocrine organs is unique; the scintigraphic images provide not only anatomic and localization information, but in many instances allow a quantitative assessment of organ function. The ability to image endocrine glands is based upon the design of radionuclides and radiopharmaceuticals with characteristics to take advantage of many unique and specific biochemical and advantage of many unique and specific biochemical and metabolic functions of these tissues. The recent introduction of new radiopharmaceutical and tracers has provided the consulting endocrinologist with imaging procedures that allow localization and functional characterization not available by other single, noninvasive diagnostic modalities. This review will serve as an update of the available techniques to image and quantitate the function of the endocrine glands using the nuclear medicine approach

  20. Scintigraphic investigation of sacroiliac disease

    International Nuclear Information System (INIS)

    Lentle, B.C.; Russell, A.S.; Percy, J.S.; Jackson, F.I.

    1977-01-01

    Bone scintigraphs obtained with both technetium-99m polyphosphate and technetium-99m pyrophosphate have been abnormal at the sacroiliac joints of 44 patients with definite ankylosing spondylitis (AS). Because of the normal registration of the sacroiliac joints on bone scintigraphy, it has been necessary to develop a profile-scan technique to quantify the abnormality that proves to be significantly different from the normal finding. In 17 patients with a strong clinical suspicion of AS but normal radiographs, the sacroiliac joints have frequently been abnormal. This finding is meaningful because there is a common occurrence in this group of the histocompatibility antigen HL A-B27, known to be a marker of AS. We also note the frequency of abnormal sacroiliac scintigrams in 26 patients with rheumatoid arthritis and in a group of other diseases--Crohn's disease, uveitis, psoriasis, ulcerative colitis, and Reiters' disease--all of which share some of the manifestations of AS

  1. Histiocytosis X: Scintigraphic and roentgenological findings

    International Nuclear Information System (INIS)

    Fezoulidis, I.; Wickenhauser, J.; Schurawitzki, H.; Gritzmann, N.

    1987-01-01

    The aim of this study was to compare the roentgenological and scintigraphic osseous changes in 25 resp. 18 patients with histiocytosis X and to analyse them. In particular, it was also interesting to discuss the divergent reports in the literature in respect of scintigraphic storage behaviour. In all patients examined before initiation of therapy (39 osseous foci) high activities were found scintigraphically. The extension of the scintigraphically active zone was much greater than the corresponding translucencies on the X-ray film. On the other hand, patients after therapy still showed foci on the X-ray film whereas the scan had already become inactive. This striking discrepancy between scan findings before and after therapy could be one of the reasons for divergent literature reports on this problem. (orig.) [de

  2. Scintigraphic And Ultrasonic Determinations of Thyroid Volume

    International Nuclear Information System (INIS)

    Sarsono; Ismanto; Kunto, W; Hayati, N; Irma, S H

    1996-01-01

    A study has been done on the determination of thyroid volume by scintigraphic method in comparison to ultrasonographic technique, which involved a healthy woman volunteer, 5 women patients and a man patient with thyroid diseases. Scintigraphic examination upon the patient's thyroid was performed using a gamma camera 20 minutes following the injection of 55.5 Mbq (1.5 mCi) Tc-99m pertechnetate. A computer, with a dedicated program, coupled to the gamma camera was employed in the calculation of thyroid volume based on the scintigraphic data. Subsequent to the scintigraphic study, ultrasonographic determination of thyroid volume was then carried out. Correlation test that was applied to the outcome of the two methods of thyroid volume determination resulted in an excellent coefficient of correlation, R, which was 0.99. This showed a very good correlation between these two different techniques of thyroid volume determination

  3. Scintigraphic features of cirrhosis of the liver

    Energy Technology Data Exchange (ETDEWEB)

    Bell, E; Biersack, H J; Altland, H; Albrecht, M; Winkler, C

    1980-09-01

    A retrospective study of 101 patients with histologically confirmed cirrhosis of the liver and portal hypertension was carried out in order to evaluate the accepted scintigraphic criteria. In only 20% were all the essential criteria present. The absence of generally accepted important scintigraphic signs does not exclude the diagnosis of cirrhosis of the liver. Specificity of liver scintigraphy in cirrhosis of the liver is fairly low, but sensitivity of the method is almost 100%.

  4. Scintigraphic appearance of the piriformis muscle syndrome

    International Nuclear Information System (INIS)

    Karl, R.D. Jr.; Yedinak, M.A.; Hartshorne, M.F.; Cawthon, M.A.; Bauman, J.M.; Howard, W.H.; Bunker, S.R.

    1985-01-01

    This is the first report in the nuclear medicine literature of the scintigraphic appearance of the piriformis muscle syndrome. This syndrome previously has been thought to be a purely clinical diagnosis and imaging modalities have been ignored. However, its confusing clinical presentation can lead to unnecessary surgical exploration. This case is presented to illustrate the characteristic scintigraphic pattern and suggest the role of nuclear medicine scanning in establishing the diagnosis

  5. Modeling and analysis of dynamic scintigraphic data for measurement of cardiac perfusion and performance

    International Nuclear Information System (INIS)

    Twieg, D.B.

    1977-01-01

    Clinical scintigraphy is the technique of imaging the distributions of gamma-ray-emitting tracers within a patient's body. The increasingly popular small nuclear medicine computer has greatly facilitated the use of mathematical models for interpretation of scintigraphic data, and has made it possible for the clinician and the researcher to extract from the scintigraphic data information not otherwise available. The purpose of this work was to investigate several models used in dynamic scintigraphic studies of the heart. The Xenon washout method of measuring myocardial perfusion is discussed. The use of single-compartment, multi-compartment, and noncompartmental models are critically examined, and the influence of multiexponential components on monoexponential fits for perfusion measurement from Xenon washouts is investigated. A model of cardiac pump function is developed which allows for incompetent valves at the input and output of the ventricular chamber. An iterative method is used in conjunction with the model to estimate forward and regurgitant flows from simulated noisy scintigraphic data and from patient data. Unlike previously available methods, the method presented here was developed to allow noninvasive determination of both mitral and aortic regurgitation. Simulation results were successful, and preliminary studies in a few patients were encouraging. An investigation is presented into the relationship between the count-volume and geometric scintigraphic methods of estimating left ventricular ejection fraction, an important index of the contractile state of the myocardial muscle. A bias due to failure to account for the effects of Poisson noise was found in one popular method for ejection measurement

  6. The use of remote sensing to estimate changes of seagrass extent and biomass in Cockburn Sound, Western Australia

    Science.gov (United States)

    Vidyan, S.

    2018-05-01

    The extent of seagrasses in Cockburn Sound was examined using Nearmap images of year 2010, 2012, 2014, and 2016 to be compared to the last assessment in 1999. It was identified that the seagrass coverage has increased by 231 Ha since 1999, with most of the growth occurred in the southern part. While the water quality in Cockburn Sound has improved, it is believed that there are other pressures affecting the slow growth rate of the seagrasses. Seagrass biomass was also evaluated using Landsat images of year 1994, 1999, 2010, 2012, 2014, and 2016 in addition to a field survey data of leaf biomass in 2016. Despite its increasing extent, seagrass in Cockburn Sound indicated a declining biomass since 1994, which is believed due to the changing nutrient content.

  7. Estimating the Extent and Thickness of DNAPL within the A/M Area of the Savannah River Site

    International Nuclear Information System (INIS)

    Jackson, D.G.; Payne, T.H.; Looney, B.B.; Rossabi, J.

    1996-01-01

    The objective of this study is to refine the current conceptual model for the extent, character, and thickness of DNAPL contamination in the A/M Area. The evaluation is based upon historical records of operations and waste management and on detailed screening of historical groundwater concentrations against solubility limits. The topology of the Green Clay confining zone is used as the primary factor determining DNAPL pool thickness and resulting migration paths

  8. Scintigraphic detection of remote transmural myocardial infarction with thallium-201

    International Nuclear Information System (INIS)

    Silber, S.; Fleck, E.; Bierner, M.; Klein, U.; Rudolph, W.

    1979-01-01

    This study was undertaken to assess the value of the thallium-201-scintigram in the detection of remote myocardial infarction with respect to localization and extent as well as the degree of impairment of left ventricular wall motion. 114 patients with typical history of infarction, unequivocal ECG changes and angiographically-documented irreversible asynergy were investigated and 25 healthy subjects served as controls. Electrocardiographic classification of infarction as extensive or non-extensive was based on number of leads involved. The thallium-201-scintigrams were visually analyzed for evaluation of each of 3 segments in all 6 recorded projections. The angiograms were evaluated with respect to regional wall motion derived for the semi-axis shortening of the 3 corresponding scintigraphic segments in the right and left anterior oblique projections. Standard classification of localization and degree of asynergy were employed. (orig.) 891 AJ/orig. 892 MB [de

  9. Quantifying the Extent of Emphysema : Factors Associated with Radiologists' Estimations and Quantitative Indices of Emphysema Severity Using the ECLIPSE Cohort

    NARCIS (Netherlands)

    Gietema, Hester A.; Mueller, Nestor L.; Fauerbach, Paola V. Nasute; Sharma, Sanjay; Edwards, Lisa D.; Camp, Pat G.; Coxson, Harvey O.

    Rationale and Objectives: This study investigated what factors radiologists take into account when estimating emphysema severity and assessed quantitative computed tomography (CT) measurements of low attenuation areas. Materials and Methods: CT scans and spirometry were obtained on 1519 chronic

  10. Quantitative estimation of the extent of alkylation of DNA following treatment of mammalian cells with non-radioactive alkylating agents

    Energy Technology Data Exchange (ETDEWEB)

    Snyder, R.D. (Univ. of Tennessee, Oak Ridge); Regan, J.D.

    1981-01-01

    Alkaline sucrose sedimentation has been used to quantitate phosphotriester formation following treatment of human cells with the monofunctional alkylating agents methyl and ethyl methanesulfonate. These persistent alkaline-labile lesions are not repaired during short-term culture conditions and thus serve as a useful and precise index of the total alkylation of the DNA.Estimates of alkylation by this procedure compare favorably with direct estimates by use of labeled alkylating agents.

  11. Landsat-Derived Estimates of Mangrove Extents in the Sierra Leone Coastal Landscape Complex during 1990-2016.

    Science.gov (United States)

    Mondal, Pinki; Trzaska, Sylwia; de Sherbinin, Alex

    2017-12-21

    This study provides the first assessment of decadal changes in mangrove extents in Sierra Leone. While significant advances have been made in mangrove mapping using remote sensing, no study has documented long-term changes in mangrove extents in Sierra Leone-one of the most vulnerable countries in West Africa. Such understanding is critical for devising regional management strategies that can support local livelihoods. We utilize multi-date Landsat data and cloud computational techniques to quantify spatiotemporal changes in land cover, with focus on mangrove ecosystems, for 1990-2016 along the coast of Sierra Leone. We specifically focus on four estuaries-Scarcies, Sierra Leone, Yawri Bay, and Sherbro. We relied on the k-means approach for an unsupervised classification, and validated the classified map from 2016 using ground truth data collected from Sentinel-2 and high-resolution images and during field research (accuracy: 95%). Our findings indicate that the Scarcies river estuary witnessed the greatest mangrove loss since 1990 (45%), while the Sierra Leone river estuary experienced mangrove gain over the last 26 years (22%). Overall, the Sierra Leone coast lost 25% of its mangroves between 1990 and 2016, with the lowest coverage in 2000, during the period of civil war (1991-2002). However, natural mangrove dynamics, as supported by field observations, indicate the potential for regeneration and sustainability under carefully constructed management strategies.

  12. Conflict minerals in the compute sector: estimating extent of tin, tantalum, tungsten, and gold use in ICT products.

    Science.gov (United States)

    Fitzpatrick, Colin; Olivetti, Elsa; Miller, Reed; Roth, Richard; Kirchain, Randolph

    2015-01-20

    Recent legislation has focused attention on the supply chains of tin, tungsten, tantalum, and gold (3TG), specifically those originating from the eastern part of the Democratic Republic of Congo. The unique properties of these so-called “conflict minerals” lead to their use in many products, ranging from medical devices to industrial cutting tools. This paper calculates per product use of 3TG in several information, communication, and technology (ICT) products such as desktops, servers, laptops, smart phones, and tablets. By scaling up individual product estimates to global shipment figures, this work estimates the influence of the ICT sector on 3TG mining in covered countries. The model estimates the upper bound of tin, tungsten, tantalum, and gold use within ICT products to be 2%, 0.1%, 15%, and 3% of the 2013 market share, respectively. This result is projected into the future (2018) based on the anticipated increase in ICT device production.

  13. Scintigraphic Evaluation in Primary Hyperparathyroidism

    International Nuclear Information System (INIS)

    Ghita, S.; Mazilu, C.; Marinescu, G.; Mititelu, R.; Rambu, A.; Murgoci, P.; Codorean, I.

    2006-01-01

    corresponding to those found at bone scan (left femur, right humerus, patellae); another focal uptake in the right shoulder region, visible on the posterior image. Further investigations: US, IRM, CT confirm the presence of tumour and provide precise data regarding the morphology and localization: a tumour of 50/34/25 mm with solid and cystic components and benign features developed in the left anterior cervical space, between trachea, cervical vessels and SCM, in contact with the inferior pole of the left thyroid lobe. CT of right shoulder region confirms the presence of a tumour the right scapula with features consistent with the diagnosis of brown tumour. There is also a tumour developed on the posterior aspect of the right humerus. PTH 1248.0 pg/ml (N 15-65). Minimal surgical intervention tumour ablation, followed by normalization of calcium levels. Histopathology: parathyroid adenoma. Favourable evolution of clinical and laboratory parameters. Discussion. Clinical presentation was unspecific and misleading. Based on the 'metabolic' information, bone scan was able suggest the correct diagnosis and to reorient the entire management of this patient. However, we took into account all data available: benign aspect of bone lesions on Rx, the high number of giant cells of osteoclastic type in the previously assessed tumor were concordant with the diagnostic. The scintigraphic examination with 'metabolic' radiotracer was able to identify the presence of a parathyroid adenoma. Early whole body acquisitions revealed sites of osteitis fibrosa cystica/brown tumours with better accuracy than bone scan. Further investigations were necessary to confirm the presence of tumour and to provide useful data regarding the morphology and localization. Conclusions. Bone scan has to be mandatory in the evaluation of all bone tumours, being a simple diagnostic tool which provides data about the number and localization of bone lesions, but also regarding the metabolic status of the skeleton. The

  14. Scintigraphic evaluation of gastrointestinal motility disorders

    Energy Technology Data Exchange (ETDEWEB)

    Choe, Jae Gol [College of Medicine, Korea Univ., Seoul (Korea, Republic of)

    2001-02-01

    Current scintigraphic tests of gastrointestinal motor function provides relevant pathophysiologic information, but their clinical utility is controversial. Many scintigraphic methods are developed to investigate gastrointestinal motility from oral cavity to colon. These are esophageal transit scintigraphy, oropharyngeal transit study, gastric emptying test, small bowel transit time measurement, colon transit study and gastroesopahgeal reflux scintigraphy. Scintigraphy of gastrointestinal tract is the most physiologic and noninvasive method to evaluate gastrointestinal motility disorders. Stomach emptying test is regarded as a gold standard in motility study. Gastrointestinal transit scintigraphy also has a certain role in assessment of drug effect to GI motility and changes after theraphy of motility disorders. Scintigraphy provides noninvasive and quantitative assessment of physiological transit throughout the gastrointestinal tract, and it is extremely useful for diagnosing gastrointestinal motor dysfunction. This article reviews the current procedures, indications, significance and guidelines for gastrointestinal motility measurements by scintigraphy.

  15. Scintigraphic evaluation of gastrointestinal motility disorders

    International Nuclear Information System (INIS)

    Choe, Jae Gol

    2001-01-01

    Current scintigraphic tests of gastrointestinal motor function provides relevant pathophysiologic information, but their clinical utility is controversial. Many scintigraphic methods are developed to investigate gastrointestinal motility from oral cavity to colon. These are esophageal transit scintigraphy, oropharyngeal transit study, gastric emptying test, small bowel transit time measurement, colon transit study and gastroesopahgeal reflux scintigraphy. Scintigraphy of gastrointestinal tract is the most physiologic and noninvasive method to evaluate gastrointestinal motility disorders. Stomach emptying test is regarded as a gold standard in motility study. Gastrointestinal transit scintigraphy also has a certain role in assessment of drug effect to GI motility and changes after theraphy of motility disorders. Scintigraphy provides noninvasive and quantitative assessment of physiological transit throughout the gastrointestinal tract, and it is extremely useful for diagnosing gastrointestinal motor dysfunction. This article reviews the current procedures, indications, significance and guidelines for gastrointestinal motility measurements by scintigraphy

  16. Gallium 67 scintigraphic examination of dilated myocardiopathies

    International Nuclear Information System (INIS)

    Lanfranchi, J.; Sachs, R.N.; Beaudet, B.; Deblock, C.; Tellier, P.

    1989-01-01

    Twenty-seven patients were diagnosed as having dilated cardiomyopathies, based on increases in the cardiothoracic index > 0.50, in the diastolic and systolic diameters of the left ventricle, and in the telediastolic volume of the left ventricle, which was indexed by body surface determined by contrast ventriculography. They underwent gallium 67 scintigraphic examination of the myocardium, in order to non-invasively detect the presence of an inflammatory infiltrate. Fifteen of them also had endomyocardial biopsies and all had virology check-up. The results were disappointing. Only in one case was the scintigraphic image undeniably positive; in 20 other patients the findings were dubious or negative. This technique did not demonstrate the presence of an inflammatory infiltrate and thus an association between myocarditis and dilated cardiomyopathy, could not be established [fr

  17. Scintigraphic presentation of hip joint synovial chondromatosis

    Energy Technology Data Exchange (ETDEWEB)

    Zwas, S T; Friedman, B; Nerubay, J

    1988-09-01

    A case of hip joint synovial chondromatosis with an unusual scintigraphic pattern is described. This pattern was suggestive of a hip joint destructive reactive articular process or late manifestations of avascular necrosis of the femoral head. Concurrent radiographs were normal, as were laboratory investigations. Follow-up radiographs six months later showed radiolucencies and erosive bone changes in the diseased joint. Surgical and histopathological findings revealed well developed hip synovial chondromatosis (HSC) with thickened synovium and large, loose, cartilaginous bodies occupying and widening the tightened joint space, with destructive secondary juxta articular pressure and bone erosions. This and other scintigraphic patterns in HSC, and the differential diagnosis of the findings in patients with painful hip presentations are discussed.

  18. The Use of CT Scans in Estimating Age at Death by Examining the Extent of Ectocranial Suture Closure

    DEFF Research Database (Denmark)

    Boyd, Kristen Leigh; Villa, Chiara; Lynnerup, Niels

    2015-01-01

    -aged individuals. ANOVA test revealed no difference between two groups of scans and between left and right sides (p > 0.05). Interobserver agreement was good, especially considering the score by sides. The results of this study create the base for developing a robust and simple method to estimate the age at death...

  19. Scintigraphic demonstration of tracheo-esophageal fistula

    International Nuclear Information System (INIS)

    Dunn, E.K.; Man, A.C.; Lin, K.J.; Kaufman, H.D.; Solomon, N.A.

    1983-01-01

    A tracheo-esophageal fistula, developed following radiotherapy for an esophageal carcinoma, was vividly demonstrated by radionuclide imaging. The abnormality was later confirmed by a barium esophagram and endoscopic examinations. The scintigraphic procedure, making use of a Tc-99m sulfur colloid swallow, appears to be a simple alternative method use of a Tc-99m sulfur colloid swallow, appears to be a simple alternative method that may be clinically useful for the diagnosis of such a condition

  20. The scintigraphic reaction pattern of traumatic bone lesions

    International Nuclear Information System (INIS)

    Spitz, J.

    1994-01-01

    The indications for bone scintigraphy in traumatology result: 1. Definite exclusion of bone lesions by normal scintigraphic findings (except for the scull). 2. Unclear result of X-ray or a mismatch between clinical investigation and X-ray result. 3. Screening after multiple injury which leads to the detection of an unknown bone lesion in every second patient. 4. Suspicion of a complicated healting course in cases of doubtful X-ray results. 5. The estimation of relative fracture age. This question always rises, if a pre-existing trauma or morphologic changes in X-ray make a clear diagnosis impossible. The additional information gained by bone scintigraphy is in part exclusive and not to be drawn from any other imaging modality. This renders bone scintigraphy to an important tool in the work up of medico-legal questions in traumatology. (orig.) [de

  1. A review of surface energy balance models for estimating actual evapotranspiration with remote sensing at high spatiotemporal resolution over large extents

    Science.gov (United States)

    McShane, Ryan R.; Driscoll, Katelyn P.; Sando, Roy

    2017-09-27

    Many approaches have been developed for measuring or estimating actual evapotranspiration (ETa), and research over many years has led to the development of remote sensing methods that are reliably reproducible and effective in estimating ETa. Several remote sensing methods can be used to estimate ETa at the high spatial resolution of agricultural fields and the large extent of river basins. More complex remote sensing methods apply an analytical approach to ETa estimation using physically based models of varied complexity that require a combination of ground-based and remote sensing data, and are grounded in the theory behind the surface energy balance model. This report, funded through cooperation with the International Joint Commission, provides an overview of selected remote sensing methods used for estimating water consumed through ETa and focuses on Mapping Evapotranspiration at High Resolution with Internalized Calibration (METRIC) and Operational Simplified Surface Energy Balance (SSEBop), two energy balance models for estimating ETa that are currently applied successfully in the United States. The METRIC model can produce maps of ETa at high spatial resolution (30 meters using Landsat data) for specific areas smaller than several hundred square kilometers in extent, an improvement in practice over methods used more generally at larger scales. Many studies validating METRIC estimates of ETa against measurements from lysimeters have shown model accuracies on daily to seasonal time scales ranging from 85 to 95 percent. The METRIC model is accurate, but the greater complexity of METRIC results in greater data requirements, and the internalized calibration of METRIC leads to greater skill required for implementation. In contrast, SSEBop is a simpler model, having reduced data requirements and greater ease of implementation without a substantial loss of accuracy in estimating ETa. The SSEBop model has been used to produce maps of ETa over very large extents (the

  2. Method for estimating potential wetland extent by utilizing streamflow statistics and flood-inundation mapping techniques: Pilot study for land along the Wabash River near Terre Haute, Indiana

    Science.gov (United States)

    Kim, Moon H.; Ritz, Christian T.; Arvin, Donald V.

    2012-01-01

    Potential wetland extents were estimated for a 14-mile reach of the Wabash River near Terre Haute, Indiana. This pilot study was completed by the U.S. Geological Survey in cooperation with the U.S. Department of Agriculture, Natural Resources Conservation Service (NRCS). The study showed that potential wetland extents can be estimated by analyzing streamflow statistics with the available streamgage data, calculating the approximate water-surface elevation along the river, and generating maps by use of flood-inundation mapping techniques. Planning successful restorations for Wetland Reserve Program (WRP) easements requires a determination of areas that show evidence of being in a zone prone to sustained or frequent flooding. Zone determinations of this type are used by WRP planners to define the actively inundated area and make decisions on restoration-practice installation. According to WRP planning guidelines, a site needs to show evidence of being in an "inundation zone" that is prone to sustained or frequent flooding for a period of 7 consecutive days at least once every 2 years on average in order to meet the planning criteria for determining a wetland for a restoration in agricultural land. By calculating the annual highest 7-consecutive-day mean discharge with a 2-year recurrence interval (7MQ2) at a streamgage on the basis of available streamflow data, one can determine the water-surface elevation corresponding to the calculated flow that defines the estimated inundation zone along the river. By using the estimated water-surface elevation ("inundation elevation") along the river, an approximate extent of potential wetland for a restoration in agricultural land can be mapped. As part of the pilot study, a set of maps representing the estimated potential wetland extents was generated in a geographic information system (GIS) application by combining (1) a digital water-surface plane representing the surface of inundation elevation that sloped in the downstream

  3. Pharyngeal transit time measured by scintigraphic and biomagnetic method

    International Nuclear Information System (INIS)

    Miquelin, C.A.; Braga, F.J.H.N.; Baffa, O.

    1996-01-01

    A comparative evaluation between scintigraphic and biomagnetic method to measure the pharyngeal transit is presented. Three volunteers have been studied. The aliment (yogurt) was labeled with 9 9 m Technetium for the scintigraphic test and with ferrite for the biomagnetic one. The preliminary results indicate a difference between the values obtained, probably due to the biomagnetic detector resolution

  4. Congenital vascular malformations in scintigraphic evaluation

    International Nuclear Information System (INIS)

    Pilecki, Stanisław; Gierach, Marcin; Gierach, Joanna; Świętaszczyk, Cyprian; Junik, Roman; Lasek, Władysław

    2014-01-01

    Congenital vascular malformations are tumour-like, non-neoplastic lesions caused by disorders of vascular tissue morphogenesis. They are characterised by a normal cell replacement cycle throughout all growth phases and do not undergo spontaneous involution. Here we present a scintigraphic image of familial congenital vascular malformations in two sisters. A 17-years-old young woman with a history of multiple hospitalisations for foci of vascular anomalies appearing progressively in the upper and lower right limbs, chest wall and spleen. A Parkes Weber syndrome was diagnosed based on the clinical picture. Due to the occurrence of new foci of malformations, a whole-body scintigraphic examination was performed. A 12-years-old girl reported a lump in the right lower limb present for approximately 2 years, which was clinically identified as a vascular lesion in the area of calcaneus and talus. Phleboscintigraphy visualized normal radiomarker outflow from the feet via the deep venous system, also observed in the superficial venous system once the tourniquets were released. In static and whole-body examinations vascular malformations were visualised in the area of the medial cuneiform, navicular and talus bones of the left foot, as well as in the projection of right calcaneus and above the right talocrural joint. People with undiagnosed disorders related to the presence of vascular malformations should undergo periodic follow-up to identify lesions that may be the cause of potentially serious complications and to assess the results of treatment. Presented scintigraphic methods may be used for both diagnosing and monitoring of disease progression

  5. Dynamic scintigraphic studies after oesophageal reconstruction

    International Nuclear Information System (INIS)

    Maliska, C.M.; Maliska, C.; Pinto, E.; Castro, L.; Fonseca, L.B.E; Miranda, M.

    1997-01-01

    Full text: We have studied the oesophageal transit and gastric emptying in the monitoring of the effect of oesophageal reconstruction surgery. Oncologic patients were evaluated after oesophageal reconstruction surgery with gastric (14 patients) or colonic (5 patients) tube and they were compared with 15 healthy volunteers, using scintigraphic method with liquid food (S-colloid-Tc99m). In the oesophageal transit studies there were no significant statistical differences among the three groups, when we have just considered to two superior (of the three) segments, as oesophagus, showing that the distal neo-tube works just like the stomach of normal volunteers

  6. Serendipity in scintigraphic gastrointestinal bleeding studies

    International Nuclear Information System (INIS)

    Goergen, T.G.

    1983-01-01

    A retrospective review of 80 scintigraphic bleeding studies performed with Tc-99m sulfur colloid or Tc-99m labeled red blood cells showed five cases where there were abnormal findings not related to bleeding. In some cases, the abnormalities were initially confused with bleeding or could obscure an area of bleeding, while in other cases, the abnormalities represented additional clinical information. These included bone marrow replacement related to tumor and radiation therapy, hyperemia related to a uterine leiomyoma and a diverticular abscess, and a dilated abdominal aorta (aneurysm). Recognition of such abnormalities should prevent an erroneous diagnosis and the additional information may be of clinical value

  7. Estimation and quantification of mangrove forest extent by using different spatial resolution satellite data for the sandspit area of Karachi coast

    International Nuclear Information System (INIS)

    Saeed, U.; Daud, A.; Ashraf, S.; Mahmood, A.

    2006-01-01

    Mangrove forest is an integral part of inter-tidal zone of the coastal environment extending throughout the tropics and subtropics of the world. In Pakistan, for the last thirty years, remote-sensing data has significantly been used for area estimation of mangrove forests. In the previous studies medium resolution satellite data have been used for the area estimation of mangrove forests that revealed some of the discrepancies in terms of recognition of the subtle variations of landcover features in the satellite imagery. Current study aims at the classification techniques employed for the area estimation using high and medium resolution satellite imageries. To study the effects of spatial resolution on classification results, three different satellite data were used, including Quickbird, TERRA and Landsat satellites. Thematic map derived from Quickbird data was comprised of maximum number of land cover classes with a definite zone of mangroves that extends from regeneration to mature canopies. Total estimated mangroves extent was 370 ha with 57.45, 125.9, 180.89, and 5.35 ha of tall, medium, small, and new recruitment mangrove plants respectively. While mangrove area estimations from thematic maps derived using TERRA and Landsat satellite data, showed a gradual increase in the mangrove extent from 390.95 ha to 417.92 ha. This increase in area is an indicative of the fact that some of the landcover classes may have been miss-classified and hence added to the area under mangrove forests. This study also showed that high-resolution satellite data could be used for identifying different height zones of mangrove forests, along with an accurate delineation of classes like salt bushes and algae, which could not be classified otherwise. (author)

  8. Scintigraphic defecography in various anorectal disorders

    Energy Technology Data Exchange (ETDEWEB)

    Ishii, Yuji; Oya, Masatoshi; Ishikawa, Hiroshi [Dokkyo Univ., School of Medicine, Saitama (Japan). Koshigaya Hospital

    1998-04-01

    Scintigraphic defecography was performed using {sup 99m}Tc-DATA to quantitatively evaluate defecation in 26 patients after low anterior resection of rectal cancer (LAP-group), 19 patients with chronic constipation (C-group), 11 patients with miscellaneous anal symptoms (AN-group), and 12 normal volunteers. After introducing semi-solid artificial stool containing {sup 99m}Tc-DTPA into the rectum, right lateral images of the anorectum were serially obtained during voluntary evacuation. From the time activity curve of the whole rectum, the half emptying time (T1/2) and the percentage of rectal evacuation (evacuation ratio) were calculated. Three abnormal patterns were identified: the flat type in which a temporary elevation of the RI activity, usually recorded in normal volunteers at the beginning of evacuation, was not recorded; the slow type in which T1/2 was over 20 seconds; and the poor evacuation type in which evacuation ratio was less than 80%. In the LAR-group, all the patients having very low anastomosis showed abnormal patterns irrespective of the type of reconstruction (straight or colonic J-pouch). In the C-group, 10 patients who had either slow pattern or poor evacuation pattern were suggested to have outlet obstruction. In the AN-group, the evacuation pattern differed from patient to patient. Scintigraphic defecography is useful in identifying abnormal evacuation in various anorectal disorders. (author)

  9. Scintigraphic defecography in various anorectal disorders

    International Nuclear Information System (INIS)

    Ishii, Yuji; Oya, Masatoshi; Ishikawa, Hiroshi

    1998-01-01

    Scintigraphic defecography was performed using 99m Tc-DATA to quantitatively evaluate defecation in 26 patients after low anterior resection of rectal cancer (LAP-group), 19 patients with chronic constipation (C-group), 11 patients with miscellaneous anal symptoms (AN-group), and 12 normal volunteers. After introducing semi-solid artificial stool containing 99m Tc-DTPA into the rectum, right lateral images of the anorectum were serially obtained during voluntary evacuation. From the time activity curve of the whole rectum, the half emptying time (T1/2) and the percentage of rectal evacuation (evacuation ratio) were calculated. Three abnormal patterns were identified: the flat type in which a temporary elevation of the RI activity, usually recorded in normal volunteers at the beginning of evacuation, was not recorded; the slow type in which T1/2 was over 20 seconds; and the poor evacuation type in which evacuation ratio was less than 80%. In the LAR-group, all the patients having very low anastomosis showed abnormal patterns irrespective of the type of reconstruction (straight or colonic J-pouch). In the C-group, 10 patients who had either slow pattern or poor evacuation pattern were suggested to have outlet obstruction. In the AN-group, the evacuation pattern differed from patient to patient. Scintigraphic defecography is useful in identifying abnormal evacuation in various anorectal disorders. (author)

  10. An Attempt To Estimate The Contribution Of Variability Of Wetland Extent On The Variability Of The Atmospheric Methane Growth Rate In The Years 1993-2000.

    Science.gov (United States)

    Ringeval, B.; de Noblet-Ducoudre, N.; Prigent, C.; Bousquet, P.

    2006-12-01

    The atmospheric methane growth rate presents lots of seasonal and year-to-year variations. Large uncertainties still exist in the relative part of differents sources and sinks on these variations. We have considered, in this study, the main natural sources of methane and the supposed main variable source, i.e. wetlands, and tried to simulate the variations of their emissions considering the variability of the wetland extent and of the climate. For this study, we use the methane emission model of Walter et al. (2001) and the quantification of the flooded areas for the years 1993-2000 obtained with a suite of satellite observations by Prigent et al. (2001). The data necessary to the Walter's model are obtained with simulation of a dynamic global vegetation model ORCHIDEE (Krinner et al. (2005)) constrained by the NCC climate data (Ngo-Duc et al. (2005)) and after imposing a water-saturated soil to approach productivity of wetlands. We calculate global annual methane emissions from wetlands to be 400 Tg per year, that is higher than previous results obtained with fixed wetland extent. Simulations are realised to estimate the part of variability in the emissions explained by the variability of the wetland extent. It seems that the year-to-year emission variability is mainly explained by the interannual variability of wetland extent. The seasonnal variability is explained for 75% in the tropics and only for 40% in the north of 30°N by variability of wetlands extend. Finally, we compare results with a top-down approach of Bousquet et al.(2006).

  11. A novel case-control design to estimate the extent of over-diagnosis of breast cancer due to organised population-based mammography screening.

    Science.gov (United States)

    Beckmann, Kerri R; Lynch, John W; Hiller, Janet E; Farshid, Gelareh; Houssami, Nehmat; Duffy, Stephen W; Roder, David M

    2015-03-15

    Debate about the extent of breast cancer over-diagnosis due to mammography screening has continued for over a decade, without consensus. Estimates range from 0 to 54%, but many studies have been criticized for having flawed methodology. In this study we used a novel study design to estimate over-diagnosis due to organised mammography screening in South Australia (SA). To estimate breast cancer incidence at and following screening we used a population-based, age-matched case-control design involving 4,931 breast cancer cases and 22,914 controls to obtain OR for yearly time intervals since women's last screening mammogram. The level of over-diagnosis was estimated by comparing the cumulative breast cancer incidence with and without screening. The former was derived by applying ORs for each time window to incidence rates in the absence of screening, and the latter, by projecting pre-screening incidence rates. Sensitivity analyses were undertaken to assess potential biases. Over-diagnosis was estimated to be 8% (95%CI 2-14%) and 14% (95%CI 8-19%) among SA women aged 45 to 85 years from 2006-2010, for invasive breast cancer and all breast cancer respectively. These estimates were robust when applying various sensitivity analyses, except for adjustment for potential confounding assuming higher risk among screened than non-screened women, which reduced levels of over-diagnosis to 1% (95%CI 5-7%) and 8% (95%CI 2-14%) respectively when incidence rates for screening participants were adjusted by 10%. Our results indicate that the level of over-diagnosis due to mammography screening is modest and considerably lower than many previous estimates, including others for Australia. © 2014 UICC.

  12. Comparative functional scintigraphic and angiographic examination in pancreas diseases

    International Nuclear Information System (INIS)

    Mendizov, A.; Brilski, V.; Bozhiyanov, A.; Romanova, A.; Mardzhanov, I.; Glavincheva, I.; Meditsinska Akademiya, Sofia

    1979-01-01

    Pancreas scintigraphy with 75 seleno-methionine, pancreocimine-secretine test and selective abdominal angiography was carried out in patients with chronic pancreatitis, pancreas carcinoma and subjects without any pancreas diseases. Scintigraphic changes in pancreas was found in 95,6 per cent of the patients with chronic pancreatitis (136 patients), in 92 per cent of them with pancreas carcinoma (25 patients) and in 53,4 per cent from the subjects without pancreas diseases (30 examined). Pathological changes in pancreatic secretion was found in 93,4 per cent of the patients with chronic pancreatitis (105 patients), in 93,8 per cent of the subjects with pancreas carcinoma (32 patients) and only in 3,9 per cent from the examined without pancreatic diseases. The angiographic examination is informative mainly in case of tumours and cysts of the pancreas. The diagnostic potentialities of the separate methods for pancreas examination were critically assessed. The basic diagnostic problems in pancreas diseases are solved to a great extent with the combined examination with scintigraphy pancreocimine test and angiography (76 patients). (author)

  13. Liver scintigraphic features associated with alcoholism

    International Nuclear Information System (INIS)

    Drum, D.E.; Beard, J.O.

    1978-01-01

    The relationships between scintigraphic features and clinical alcoholism were studied by review of 2406 liver scintiphotos. Two distinct patterns were significantly associated with alcoholism: heterogeneous distribution of radiocolloid in the liver, and jointly increased uptake of tracer by the spleen and vertebral bone marrow. A total of 13 overall patterns were found to distinguish, with considerable reliability, alcoholics from all other patients. This finding reflects the frequency with which alcohol abuse is associated with hepatic dysfunction in hospital patients. These observations indicate an important role for the nuclear medicine physician in detection of alcoholism among patients referred for liver-spleen imaging, and they form a basis for comparison with the diagnostic efficacy of other methods of evaluating diffuse liver diseases

  14. Computer processing of dynamic scintigraphic studies

    International Nuclear Information System (INIS)

    Ullmann, V.

    1985-01-01

    The methods are discussed of the computer processing of dynamic scintigraphic studies which were developed, studied or implemented by the authors within research task no. 30-02-03 in nuclear medicine within the five year plan 1981 to 85. This was mainly the method of computer processing radionuclide angiography, phase radioventriculography, regional lung ventilation, dynamic sequential scintigraphy of kidneys and radionuclide uroflowmetry. The problems are discussed of the automatic definition of fields of interest, the methodology of absolute volumes of the heart chamber in radionuclide cardiology, the design and uses are described of the multipurpose dynamic phantom of heart activity for radionuclide angiocardiography and ventriculography developed within the said research task. All methods are documented with many figures showing typical clinical (normal and pathological) and phantom measurements. (V.U.)

  15. The scintigraphic investigation of sacroiliac disease.

    Science.gov (United States)

    Lentle, B C; Russell, A S; Percy, J S; Jackson, F I

    1977-06-01

    Bone scintigraphs obtained with both Technetium-99m polyphosphate and Technetium-99m pyrophosphate have been abnormal at the sacroiliac joints of 44 patients with definite ankylosing spondylitis (AS). Because of the normal registration of the sacroiliac joints on bone scintigraphy, it has been necessary to develop a profile-scan technique to quantify the abnormality that proves to be significantly different from the normal finding. In 17 patients with a strong clinical suspicion of AS but normal radiographs, the sacroiliac joints have frequently been abnormal. This finding is meaningful because there is a common occurence in this group of the histocompatibility antigen HL A-B27, known to be a marker of AS. We also note the frequency of abnormal sacroiliac scinitigrams in 26 patients with rheumatoid arthritis and in a group of other diseases-Crohn's disease, uveitis, psoriasis, ulcerative colitis, and Reiter's disease-all of which share some of the manifestations of AS.

  16. Computer processing of the scintigraphic image using digital filtering techniques

    International Nuclear Information System (INIS)

    Matsuo, Michimasa

    1976-01-01

    The theory of digital filtering was studied as a method for the computer processing of scintigraphic images. The characteristics and design techniques of finite impulse response (FIR) digital filters with linear phases were examined using the z-transform. The conventional data processing method, smoothing, could be recognized as one kind of linear phase FIR low-pass digital filtering. Ten representatives of FIR low-pass digital filters with various cut-off frequencies were scrutinized from the frequency domain in one-dimension and two-dimensions. These filters were applied to phantom studies with cold targets, using a Scinticamera-Minicomputer on-line System. These studies revealed that the resultant images had a direct connection with the magnitude response of the filter, that is, they could be estimated fairly well from the frequency response of the digital filter used. The filter, which was estimated from phantom studies as optimal for liver scintigrams using 198 Au-colloid, was successfully applied in clinical use for detecting true cold lesions and, at the same time, for eliminating spurious images. (J.P.N.)

  17. Fine-scale spatio-temporal variation in tiger Panthera tigris diet: Effect of study duration and extent on estimates of tiger diet in Chitwan National Park, Nepal

    Science.gov (United States)

    Kapfer, Paul M.; Streby, Henry M.; Gurung, B.; Simcharoen, A.; McDougal, C.C.; Smith, J.L.D.

    2011-01-01

    Attempts to conserve declining tiger Panthera tigris populations and distributions have experienced limited success. The poaching of tiger prey is a key threat to tiger persistence; a clear understanding of tiger diet is a prerequisite to conserve dwindling populations. We used unpublished data on tiger diet in combination with two previously published studies to examine fine-scale spatio-temporal changes in tiger diet relative to prey abundance in Chitwan National Park, Nepal, and aggregated data from the three studies to examine the effect that study duration and the size of the study area have on estimates of tiger diet. Our results correspond with those of previous studies: in all three studies, tiger diet was dominated by members of Cervidae; small to medium-sized prey was important in one study. Tiger diet was unrelated to prey abundance, and the aggregation of studies indicates that increasing study duration and study area size both result in increased dietary diversity in terms of prey categories consumed, and increasing study duration changed which prey species contributed most to tiger diet. Based on our results, we suggest that managers focus their efforts on minimizing the poaching of all tiger prey, and that future studies of tiger diet be of long duration and large spatial extent to improve our understanding of spatio-temporal variation in estimates of tiger diet. ?? 2011 Wildlife Biology, NKV.

  18. Estimating the extent of subclinical arteriosclerosis of persons with prediabetes and diabetes mellitus among Japanese urban workers and their families: a cross-sectional study.

    Science.gov (United States)

    Namekata, Tsukasa; Shirai, Kohji; Tanabe, Naohito; Miyanishi, Kunio; Nakata, Mitsuko; Suzuki, Kenji; Arai, Chikao; Ishizuka, Norio

    2016-02-24

    Diabetes mellitus (hereafter called diabetes) is considered to accelerate arteriosclerosis leading to coronary heart disease and stroke. Thus, it is important to quantitatively estimate the extent of subclinical arteriosclerosis. A new method called cardio-ankle vascular index (CAVI) is developed to reflect arterial stiffness independently from blood pressure at the time of measurement. Then, we examined if CAVI scores could discriminate the extent of arteriosclerosis between persons with prediabetes (or borderline diabetes) and with diabetes among Japanese urban workers and their families. Subjects were 9881 men and 12033 women of company employees and their families who participated in cardiovascular disease screening in Japan. Persons having diabetes and prediabetes were defined based on the criteria set by American Diabetes Association. CAVI scores were measured by VaSera VS-1000. We applied the established age-sex specific cutoff points of CAVI scores above which were determined to be abnormally high or advanced level of arteriosclerosis. To examine the association of prediabetes and diabetes with CAVI scores, CAVI scores of screening participants were converted to a binary variable: 1 for less than cutoff points and 2 for equal or greater than cutoff points or abnormally high CAVI scores. Logistic regression method was used to examine the association of prediabetes and diabetes with CAVI scores after adjusting for major cardiovascular disease (CVD) risk factors. Prevalence of abnormally high CAVI scores was significantly higher after 40 years of age among persons with diabetes than either among persons with prediabetes or among normal persons in both genders. Significantly elevated odds ratios (ORs) of abnormally high CAVI scores appeared among persons with prediabetes: 1.29 (95 % confidence interval (CI), 1.11-1.48) for men and 1.14 (CI, 1.01-1.28) for women, and among persons with diabetes: 2.41 (CI, 1.97-2.95) for men and 2.52 (CI, 1.94-3.28) for women

  19. A probabilistic approach for estimating the spatial extent of pesticide agricultural use sites and potential co-occurrence with listed species for use in ecological risk assessments.

    Science.gov (United States)

    Budreski, Katherine; Winchell, Michael; Padilla, Lauren; Bang, JiSu; Brain, Richard A

    2016-04-01

    A crop footprint refers to the estimated spatial extent of growing areas for a specific crop, and is commonly used to represent the potential "use site" footprint for a pesticide labeled for use on that crop. A methodology for developing probabilistic crop footprints to estimate the likelihood of pesticide use and the potential co-occurrence of pesticide use and listed species locations was tested at the national scale and compared to alternative methods. The probabilistic aspect of the approach accounts for annual crop rotations and the uncertainty in remotely sensed crop and land cover data sets. The crop footprints used historically are derived exclusively from the National Land Cover Database (NLCD) Cultivated Crops and/or Pasture/Hay classes. This approach broadly aggregates agriculture into 2 classes, which grossly overestimates the spatial extent of individual crops that are labeled for pesticide use. The approach also does not use all the available crop data, represents a single point in time, and does not account for the uncertainty in land cover data set classifications. The probabilistic crop footprint approach described herein incorporates best available information at the time of analysis from the National Agricultural Statistics Service (NASS) Cropland Data Layer (CDL) for 5 y (2008-2012 at the time of analysis), the 2006 NLCD, the 2007 NASS Census of Agriculture, and 5 y of NASS Quick Stats (2008-2012). The approach accounts for misclassification of crop classes in the CDL by incorporating accuracy assessment information by state, year, and crop. The NLCD provides additional information to improve the CDL crop probability through an adjustment based on the NLCD accuracy assessment data using the principles of Bayes' Theorem. Finally, crop probabilities are scaled at the state level by comparing against NASS surveys (Census of Agriculture and Quick Stats) of reported planted acres by crop. In an example application of the new method, the probabilistic

  20. Scintigraphic measurement of regional gut transit in idiopathic constipation

    International Nuclear Information System (INIS)

    Stivland, T.; Camilleri, M.; Vassallo, M.; Proano, M.; Rath, D.; Brown, M.; Thomforde, G.; Pemberton, J.; Phillips, S.

    1991-01-01

    In this study, total gut transit and regional colonic transit in patients with idiopathic constipation were measured scintigraphically. Eight patients with severe constipation were studied, none of whom had evidence of abnormal function of the pelvic floor. 99mTc-radiolabeled Amberlite resin particles with a mixed meal were used to assess gastric emptying and small bowel transit; similar particles labeled with 111In were ingested in a coated capsule that dispersed in the ileocecal region. These were used to quantify colonic transit. Five healthy volunteers were also studied. Two patients showed delayed gastric emptying and two had slow small bowel transit. Seven of the eight patients had slow colonic transit. In five, delay affected the whole colon (pancolonic inertia); in two, transit in the ascending and transverse colon was normal, but solids moved through the left colon slowly. Mean colonic transit was also measured using radiopaque markers; this technique identified the patients with slow transit, as shown by measurements of overall colonic transit by simultaneous scintigraphy. However, estimated transit through the ascending and transverse colons was considerably shorter by the radiopaque marker technique. In conclusion, idiopathic constipation is characterized by either exaggerated reservoir functions of the ascending and transverse colons and/or impairment of propulsive function in the descending colon. Particle size may influence the result of regional colonic transit tests. Transit delays in other parts of the gut suggest that, in some patients, the condition may be a more generalized motor dysfunction

  1. Scintigraphic measurement of regional gut transit in idiopathic constipation

    Energy Technology Data Exchange (ETDEWEB)

    Stivland, T.; Camilleri, M.; Vassallo, M.; Proano, M.; Rath, D.; Brown, M.; Thomforde, G.; Pemberton, J.; Phillips, S. (Gastroenterology Research Unit, Mayo Clinic, Rochester, Minnesota (USA))

    1991-07-01

    In this study, total gut transit and regional colonic transit in patients with idiopathic constipation were measured scintigraphically. Eight patients with severe constipation were studied, none of whom had evidence of abnormal function of the pelvic floor. 99mTc-radiolabeled Amberlite resin particles with a mixed meal were used to assess gastric emptying and small bowel transit; similar particles labeled with 111In were ingested in a coated capsule that dispersed in the ileocecal region. These were used to quantify colonic transit. Five healthy volunteers were also studied. Two patients showed delayed gastric emptying and two had slow small bowel transit. Seven of the eight patients had slow colonic transit. In five, delay affected the whole colon (pancolonic inertia); in two, transit in the ascending and transverse colon was normal, but solids moved through the left colon slowly. Mean colonic transit was also measured using radiopaque markers; this technique identified the patients with slow transit, as shown by measurements of overall colonic transit by simultaneous scintigraphy. However, estimated transit through the ascending and transverse colons was considerably shorter by the radiopaque marker technique. In conclusion, idiopathic constipation is characterized by either exaggerated reservoir functions of the ascending and transverse colons and/or impairment of propulsive function in the descending colon. Particle size may influence the result of regional colonic transit tests. Transit delays in other parts of the gut suggest that, in some patients, the condition may be a more generalized motor dysfunction.

  2. Scintigraphical analyses of pulmonary function in dogs

    International Nuclear Information System (INIS)

    Clercx, C.

    1988-01-01

    The main goal of this study was to develop a quantitative analysis from 99mTc aerosol inhalation/perfusion (I/P) lung scintigrams. In particular attention was focused on both the regional I/P distribution, concerning the ratio of the mean I and P values in several lung regions, as well as on the local (intraregional) distribution of I/P, under a wide range of circumstances. In Ch. 2, the method and reference material are described. The distribution of the inhalation-to-perfusion ratios (I/P) is studied in anesthetized healthy dogs, with emphasis on inter-regional distribution and intra-regional dispersion of the I/P ratio. Moreover, it provides an insight into canine pulmonary physiology, frequently transposed from human lung physiology, what is not always correct. Ch. 3 deals with the possible methodological and physiological influences on the interpretation of scintigraphical measurements, such as age, posture and breed. Investigation of the effects of age and breed was pursued using qualitative studies of canine lung surfactant. The actual knowledge in this field lets prospect veterinary clinical meaning in the future. Finally in Ch. 4, the diagnostic value of the measurements was examined in experimental models of important lung disorders with different pathophysiological features, such as lobar and sublobar airway obstruction, and lung embolism. It also permits the investigation of the relative contribution of different compensating mechanisms upon the ventilation-to-perfusion ratio, such as collateral ventilation and hypoxic vasoconstriction. 218 refs.; 31 figs.; 14 tabs

  3. Scintigraphic instruments and techniques in nuclear medicine

    International Nuclear Information System (INIS)

    Bornand, B.; Soussaline, F.

    1977-03-01

    The development of new radiopharmaceuticals, cyclotron-produced radionuclides and improvement of detector, scanner and gamma camera characteristics have enable a remarkable recent progress in scintigraphic techniques for organ visualization and functional studies. Using a variety of techniques, positron cameras, section scanners, gamma holography, tomographic imaging appear to be playing an increasing important role. Data processing techniques, for example image processing and three dimensional reconstruction have significantly increased their impact. The principal research work and advances in technique achieved up to 1972 are summarized and the subjects which have been further exploited are outlined. The main section comprises references and abstracts of articles from scientific journals and conference proceedings (191 articles and 221 papers mentioned) for the period 1972-1975 to illustrate advances in this domain: Excerpta Medica (Nuclear Medicine) Abstract Journals and Nuclear Science Abstracts (1972-1975) were used as abstracting publications. This survey is completed with an index of authors and subject-matters. Eleven thesis are mentionned in an appendix [fr

  4. The new techniques of scintigraphic imaging

    International Nuclear Information System (INIS)

    Chatal, J.F.

    1990-01-01

    The purpose of scintigraphic imaging is not to explore the morphology of an organ (or its abnormalities) but rather its functional and metabolic characteristics. It is thus important that a molecular structure (e.g., a hormonal receptor or an antigen) closely linked to the functional activity of an organ or tissue be targeted on its cell surface. Such diagnostic targeting requires the synthesis and labeling of a radiopharmaceutical substance specific for the receptor or antigen in question. It also requires a detection system adapted to count rates and signal-to-background ratios (generally moderate). The synthesis of new radiopharmaceutical agents, a critical stage for the future of nuclear medicine, is a long and often risky process in which success is difficult to foresee. Radiolabeling must be stable in vitro and in vivo, and the radiopharmaceutical must subsequently retain its capability of recognizing the targeted molecule. In endocrinology, the exemplary achievement in this direction has been the synthesis of 131 I-6-iodomethylnorcholesterol and 131 I-metaiodobenzylguanidine for functional scintigraphy of the adrenal cortex and medulla. Progress in detection equipment has been marked by the development of monophotonic tomoscintigraphy, using gamma cameras with a revolving head to obtain slices in different spatial planes showing the distribution in the organism of the injected radiopharmaceutical agent [fr

  5. Scintigraphic characteristics of experimental myocardial infarct extension

    International Nuclear Information System (INIS)

    Kronenberg, M.W.; Wooten, N.E.; Friesinger, G.C.; Page, D.L.; Higgins, S.B.; Collins, J.C.; O'Connor, J.L.; Price, R.R.; Brill, A.B.

    1979-01-01

    Technetium-99m-stannous pyrophosphate scintiphotos were evaluated for diagnosing and quantitating myocardial infarct (MI) extension in sedated dogs. Infarction and extension were produced by serial left anterior descending coronary artery ligations at 0 and 48 hours. We compared serial scintiphoto data with regional myocardial blood flow (MBF) (microsphere technique) and infarct histopathology. In eight control dogs, the scintigraphic MI area was stable at 24, 48, and 72 hours. In each of 11 dogs undergoing extension, the MI area increased after the 48-hour occlusion, averaging a 48.9% increase (p < 0.001). Grossly, most extensions were mixtures of confluent necrosis and moderate (patchy) necrosis. MBF to confluent infarct tissue decreased significantly, allowing the documentation of extension by totaling the grams of newly flow-deprived tissue, but patchy infarct tissue had little flow deprivation, making it difficult to quantitate this type of extension accurately by flow criteria alone. Rarely, extension could be diagnosed using conventional histologic criteria. We concluded that the scintiphoto MI area was related quantitatively to infarct weight in both control and extension. However, it was not possible to determine that an increase in the MI scintiphoto area was an accurate predictor of the degree of extension using independent flow or pathologic criteria

  6. Scintigraphic diagnosis of the gastro-esophageal reflux

    Energy Technology Data Exchange (ETDEWEB)

    Pfluecke, F.; Krueger, M.; Reinke, R.; Groth, P. (Rostock Univ. (German Democratic Republic). Radiologische Klinik)

    1982-09-01

    Patients with peptic esophagitis or typical complaints with respect to reflux without esophagitis and control persons (n = 68) were comparatively examined for gastroesophageal reflux by means of scintigraphy (after administration of test solutions labelled with /sup 99m/Tc-DTPA or after intravenous application of /sup 99m/Tc-pertechnetate) and by means of continuous intraesophageal p/sub H/ measurement. The scintigraphic test of the reflux was successful for very few patients only with reflux disease and a reflux detectable by measuring the p/sub H/. The application of pentagastrin failed in improving the scintigraphic detection of the reflux. The cause of the unsuccessful scintigraphic evidence for the majority of the reflux patients seems to be the relatively small reflux volume.

  7. Scintigraphic diagnosis of the gastro-esophageal reflux

    International Nuclear Information System (INIS)

    Pfluecke, F.; Krueger, M.; Reinke, R.; Groth, P.

    1982-01-01

    Patients with peptic esophagitis or typical complaints with respect to reflux without esophagitis and control persons (n = 68) were comparatively examined for gastroesophageal reflux by means of scintigraphy (after administration of test solutions labelled with /sup 99m/Tc-DTPA or after intravenous application of /sup 99m/Tc-pertechnetate) and by means of continuous intraesophageal p/sub H/ measurement. The scintigraphic test of the reflux was successful for very few patients only with reflux disease and a reflux detectable by measuring the p/sub H/. The application of pentagastrin failed in improving the scintigraphic detection of the reflux. The cause of the unsuccessful scintigraphic evidence for the majority of the reflux patients seems to be the relatively small reflux volume

  8. Estimation of clinical efficacy for scintigraphic images of liver, 1

    International Nuclear Information System (INIS)

    Matsumoto, Toru; Iinuma, Takeshi; Tateno, Yukio; Machida, Kikuo.

    1982-01-01

    In this study, the clinical efficacy No. 1 (diagnostic accuracy) of liver images on various liver diseases is investigated. From 8 different medical institutions the liver images of 406 cases most of which were imaged with 99mTc-phytate and confirmed for its final diagnosis by the autopsy, surgery and other techniques excluding the liver scintigraphy were collected. In order to evaluate the results of image reading, an input sheet for computer was designed to describe the confirmed diagnosis of each case. The liver images were read by 11 physicians from the 8 institutions that presented the cases and the results of reading were recorded on the work sheet for computer input. The work sheet includes abnormality in shape, size and position of the liver, position and number of SOL, and diagnosis of liver diseases, etc. By comparing the record of confirmed diagnosis and the results of image reading for individual case, various programs of analysis are being undertaken. The accuracy in detecting the SOL by means of receiver operating characteristic (ROC) analysis is presented here. The results of analysis are as follows. (1) ROC curves are rather similar in all physicians and average ROC points are TPR = 71, 80, 91%, FPR = 5, 15, 27%, respectively. (2) The SOL of size larger than 3 cm are detected more easily than those of size less than 3 cm, although number of SOL less than 3 cm is only nine cases and so variation of TPR between physicians is large. It is found that the ROC curve for many SOL of small size is almost identical to that of SOL larger than 3 cm. As to the detection of SOL larger than 3 cm, Anger camera and scanner are found to have an identical capability. (author)

  9. Quantitative and regional evaluation methods for lung scintigraphs

    International Nuclear Information System (INIS)

    Fichter, J.

    1982-01-01

    For the evaluation of perfusion lung scintigraphs with regard to the quantitative valuation and also with regard to the choice of the regions new criteria were presented. In addition to the usual methods of sectioning each lung lobe into upper, middle and lower level and the determination of the per cent activity share of the total activity the following values were established: the median of the activity distribution and the differences of the per cent counting rate as well as of the median of the corresponding regions of the right and left lung. The individual regions should describe the functional structures (lobe and segment structure). A corresponding computer program takes over the projection of lobe and segment regions in a simplified form onto the scintigraph with consideration of individual lung stretching. With the help of a clinical study on 60 patients and 18 control persons with 99mTc-MAA and 133 Xe-gas lung scintigraphs the following results could be determined: depending on the combination of the 32 parameters available for evaluation and the choice of regions between 4 and 20 of the 60 patients were falsely negatively classified and 1 to 2 of the 18 controls were falsely positive. The accuracy of the Tc-scintigraph proved to be better. All together using the best possible parameter combinations comparative results were attained. (TRV) [de

  10. Scintigraphic evaluation of the sacroiliac joints in anklylosing spondylitis

    International Nuclear Information System (INIS)

    Schoerner, W.

    1980-01-01

    The sedimentation of sup(99m)Tc-phosphate complexes into the sacroiliac joints was investigated in 94 patients with loin pains and suspected of ankylosing spondylitis (SpA) and a control group of 96 healthy patients. The investigation yields the following results: 1. the visual evaluation of the scintigrams does not allow a reliable diagnosis and should be replaced by a semi-quantitative technique, 2. the index ISC/sacrum does remarkably depend on age, 3rd even in young patients the scintigraphic examination appears to be useful to alidate the clinical suspicion of sacroilictis which is in contradiction to literature, 4th with increasing SpA the scintigraphic detectability of changes in the ISG decreases. 5th the floriditily of the ISG process determines the scintigraphic detectability of the process of the disease, 6th the scintigraphic finding is unspecific. Inflammatory states of the disease of different genesis and degenerative processes in the ISG equally yield pathological index values. (orig./MG) [de

  11. Scintigraphic evidence of transplanted hepatocytes in spleen and liver

    International Nuclear Information System (INIS)

    Henne-Bruns, D.; Kremer, B.; Gramminger, K.; Broelsch, C.

    1986-01-01

    In rats suffering from hepatic enzymatic deficiency transplanted hepatocytes could be evidenced scintigraphically in liver, spleen and granulomas. In pigs, however, it is very difficult to demonstrate transplanted hepatocytes by scintiscanning because of the thickness of the tissues and the high background radiation in large animals

  12. Scintigraphic analysis of thyroid diseases at the Lagos University ...

    African Journals Online (AJOL)

    This paper presents a retrospective analysis of randomly selected clinical scintigraphic records at the College of Medicine/Lagos University Teaching Hospital, Nigeria. Out of the 436 patients scanned for various thyroid abnormalities, 266 (61.0%) were used for the analysis due to insufficient data and parameters required ...

  13. Scintigraphic evaluation of the esophageal-gastric function

    International Nuclear Information System (INIS)

    Taillefer, R.; Lefebvre, B.; Beauchamp, G.

    1986-01-01

    The authors present a brief review of the use of radionuclides in the pathophysiological evaluation of both esophageal and gastric function. Technical indications of these three following scintigraphic procedures are discussed: radionuclide esophagogram; gastro-esophogeal reflux study; and gastric emptying study

  14. Scintigraphic pattern of small bowel bleeding

    International Nuclear Information System (INIS)

    Anshu Rajnish Sharma; Charan, S.; Silva, I.

    2004-01-01

    camera fitted with LEAP collimator. Delayed imaging up to 6 hours was optional and was undertaken only when first 90 minutes images did not reveal any site of bleeding. Two nuclear physicians reviewed the sequential static images for 1) First appearance of focus of activity in a particular quadrant/region of abdomen and 2) looking for its migration pattern. Scintigraphic results were prospectively compared with surgical outcome in 10 patients. Results: Tc-99m RBC Scan localized site of bleeding in 10 of 13 patient evaluated (77%). Ten scan positive patients underwent exploratory laprotomy. On surgical exploration, five culprit lesions were identified in jejunum and as many number of lesions were detected in ileum. Etiological lesions were mainly inflammatory or ulcerative (n=5) followed by neoplastic and vascular ectasias in 2 patients each. One patient showed diverticular disease of jejunum as the source of haemorrhage.Tc-99m RBC Scan was able to distinguish between proximal (jejunal) and distal (ileal) small bowel bleeding in 8 of 10 scan positive cases (80%). Scintigraphy correctly localized bleeding in jejunum and ileum in 3 and 5 patients respectively. In majority of patients (7/10, 70%), scan became positive within 3 hours. Six types of scan patterns were noticed in thirteen patients evaluated with Tc-99m RBCs scan. Five scintigraphic patterns were representative of small bowel bleeding. A serpentine appearance of bowel loops in mid abdomen, focal tracer appearance in right iliac region with subsequent outlining of ascending colon on delayed images, and a focus of activity showing distal extension in circular fashion on sequential static images were characteristic of ileal bleeding. Visualization of fixed loop in left flank region corroborated with jejunal lesion (Leiomyoma) in our series. An abnormal blush and early localization of diffuse activity in left upper quadrant followed by its centripetal extension/movement, was seen in patient with jejunitis

  15. Acute rhabdomyolysis of the soleus muscle induced by a lightning strike: magnetic resonance and scintigraphic findings

    International Nuclear Information System (INIS)

    Watanabe, Naofumi; Inaoka, Tsutomu; Shuke, Noriyuki; Takahashi, Koji; Aburano, Tamio; Chisato, Naoyuki; Go, Kazutomo; Nochi, Hitoshi

    2007-01-01

    Among natural disasters, a lightning strike is a rare but potentially life-threatening phenomenon. If victims survive a cardiac arrest due to instantaneous passage of an exceptionally high voltage electric charge through the whole body, they may be afflicted with various complications such as muscle necrosis resulting in acute renal failure. In this article, we report a case of a 54-year-old man with acute rhabdomyolysis of the left soleus muscle associated with a lightning strike. T2-weighted and short-tau inversion recovery MR images showed a high signal intensity in the left soleus muscle. A whole-body bone scintigram showed abnormal uptakes in the left soleus muscle and the dorsal aspect of the left foot. MR and scintigraphic evaluations were very useful in depicting the site and extent of muscle damage. Since the patient showed a surprisingly high level of serum creatine kinase, the added information was very valuable for determining the patient's management. (orig.)

  16. Scintigraphic assessment of ectopic splenic tissue localization and function following splenectomy for trauma

    Energy Technology Data Exchange (ETDEWEB)

    Zwas, S.T.; Samra, D.; Samra, Y.; Sibber, G.R.

    1986-07-01

    Twenty-three subjects who had a splenectomy as a result of trauma underwent scintigraphic evaluation with a sensitive heat-denatured sup(99m)Tc-labeled red blood cells (DRBC). This method enabled detection of ectopic splenic tissue foci (ESTF) as small as 1x1 cm in diameter. ESTF splenosis or accessory spleen was detected in 15 cases (65%), a higher incidence than previously reported. The size of the ESTF ranged from 1x1 to 5x10 cm (0.8-40 cm/sup 2/), and 53% were less than 2x2 cma (3 cm/sup 2/). A new multiparametric scintigraphic evaluating technique is described, which estimates the quantity of ESTF and its grade of activity, relative to that of the liver. The technique is a highly efficient assessor of ESTF function. Good correlation was found between the size and activity of the ESTF and the presence of Howell-Jolly bodies (HJB), but with a low sensitivity for detecting small ESTF. Correlation was low between residual splenic tissue and concentrations of IgM, IgA and IgG immunoglobulins. The sup(99m)Tc-DRBC method described is recommended for verification of ESTF existence, localization, and function.

  17. Scintigraphic assessment of ectopic splenic tissue localization and function following splenectomy for trauma

    International Nuclear Information System (INIS)

    Zwas, S.T.

    1986-01-01

    Twenty-three subjects who had a splenectomy as a result of trauma underwent scintigraphic evaluation with a sensitive heat-denatured sup(99m)Tc-labeled red blood cells (DRBC). This method enabled detection of ectopic splenic tissue foci (ESTF) as small as 1x1 cm in diameter. ESTF splenosis or accessory spleen was detected in 15 cases (65%), a higher incidence than previously reported. The size of the ESTF ranged from 1x1 to 5x10 cm (0.8-40 cm 2 ), and 53% were less than 2x2 cma (3 cm 2 ). A new multiparametric scintigraphic evaluating technique is described, which estimates the quantity of ESTF and its grade of activity, relative to that of the liver. The technique is a highly efficient assessor of ESTF function. Good correlation was found between the size and activity of the ESTF and the presence of Howell-Jolly bodies (HJB), but with a low sensitivity for detecting small ESTF. Correlation was low between residual splenic tissue and concentrations of IgM, IgA and IgG immunoglobulins. The sup(99m)Tc-DRBC method described is recommended for verification of ESTF existence, localization, and function. (orig.)

  18. Assessment of skeleton scintigraphic study in breast cancer patients (relative to 322 observations)

    International Nuclear Information System (INIS)

    Liechtmaneger, Nicole.

    1976-01-01

    The results of scintigraphic whole-skeleton examinations have recently been improved by the use of sup(99m)Tc labelled phosphorus compounds. An assessment was made of 368 explorations, most of which were carried out with pyrophosphates and a few, the most recent, with ethane hydroxy diphosphonate, both labelled with sup(99m)Tc. For pyrophosphates a 10 mCi intraveinous injection is followed by a latency time of about 3 hours before the scintigraphic examination. In the case of diphosphonates, which have only been used lately and on relatively few cases, the same 10 mCi intravenous injection is administered but the latency time before the examination is only half as long, i.e. about 1h30 min, which is a definite advantage. However the number of examinations carried out with the latter is too small to afford a significant comparison between the two products. The main object of this work is to count the hyperfixation centres and to estimate their specificity and their coexistence or otherwise with clinical or radiological signs [fr

  19. Scintigraphic follow-up of fracture healing in animals

    International Nuclear Information System (INIS)

    Klug, W.; Franke, W.G.; Schulze, M.

    1983-01-01

    Secondary bone fracture heating was analysed by scintigraphic follow-up studies in rabbits using sup(99m)Tc-HEDP. 24 hours after fracture the activity ratio between the fractured and the non-fractured lower limb was 2,2. The maximal count density in the fracture region is found during the 14th and 28th day after fracture. Concomitantly there is a significant increase of bone marrow vessels and content of copper, magnesium, sodium and water in the callus. Although roentgenographic controls and static investigations with respect to consolidation reveal a complete heating already 126 days after fracture, the complete scintigraphic normalisation of the lower limb fracture of the rabbit is found not earlier than at the 203rd day after fracture. (orig.) [de

  20. Scintigraphic follow-up of fracture healing in animals

    Energy Technology Data Exchange (ETDEWEB)

    Klug, W.; Franke, W.G.; Schulze, M.

    1983-08-01

    Secondary bone fracture healing was analysed by scintigraphic follow-up studies in rabbits using sup(99m)Tc-HEDP. 24 hours after fracture the activity ratio between the fractured and the non-fractured lower limb was 2,2. The maximal count density in the fracture region is found during the 14th and 28th day after fracture. Concomitantly there is a significant increase of bone marrow vessels and content of copper, magnesium, sodium and water in the callus. Although roentgenographic controls and static investigations with respect to consolidation reveal a complete healing already 126 days after fracture, the complete scintigraphic normalisation of the lower limb fracture of the rabbit is found not earlier than at the 203rd day after fracture.

  1. Radiographic and scintigraphic evaluation of total knee arthroplasty

    International Nuclear Information System (INIS)

    Schneider, R.; Soudry, M.

    1986-01-01

    Various radiographic and scintigraphic methods are used to supplement clinical findings in the evaluation of total knee arthroplasty and its complications. Serial roentgenograms offer reliable information for diagnosing mechanical loosening. Wide and extensive radiolucency at the cement-bone interface and shift in position and alignment of prosthetic components can be seen in almost all cases by the time revision is necessary. Radiographic abnormalities are usually not present in acute infection, but are often present in chronic infection. Bone scanning has a high sensitivity for diagnosis of infection or loosening, but is nonspecific because increased uptake is often present around asymptomatic total knee arthroplasties with normal radiographs. Differential bone and Gallium scanning and scanning with Indium 111-labeled leukocytes have a greater specificity for diagnosis of infection than does bone or Gallium scanning alone. Routine radiographic and scintigraphic studies have shown a high incidence of deep vein thrombosis in the calf after total knee arthroplasty. Clinically significant pulmonary embolization is infrequent

  2. Survey of 26 suprarenal scintigraphs on Cushing's syndrome patients

    International Nuclear Information System (INIS)

    Venot, A.; Luton, J.P.; Roucayrol, J.C.; Bricaire, H.

    On the basis of the results of 26 Cushing's syndrome examinations some new scintigraphic aspects are described, suprarenal scintigraphy is compared with retroperitoneal insufflation, its value in the observation of a medical treatment of Cushing's disease is demonstrated and finally some preliminary results are given on the application in the same pathological context, of 75 Se-6-selenocholesterol which was compared with 131 I-19-iodocholesterol [fr

  3. Gastroesophageal reflux disease. Scintigraphic, endoscopic and histologic considerations

    Energy Technology Data Exchange (ETDEWEB)

    Kault, B.; Halvorsen, T.; Petersen, H.; Grette, K.; Myrvold, H.E.

    1986-01-01

    Radionucleotide scintigraphy and esophagoscopy with biopsy were carried out in 101 patients with symptoms strongly suggestive of gastroesophageal reflux (GER) disease. GER was visualized by scintigraphy in 86.1% of the patients. Endoscopic and histologic esophagitis were found in 68.1% and 58.4% of the patients, respectively, whereas both examinations taken together showed evidence of esophagitis in 82%. Histologic evidence of esophagitis was found in nearly all patients with severe endoscopic changes, and in 43.7% of the patients with no endoscopic abnormality. Scintigraphic reflux was demonstrated more frequently in the patients with severe endoscopic esophagitis (97.5%) than in those with no or only mild endoscopic changes (78.6%). Scintigraphic reflux was found in 91.5% and 78.5% of the patients with and without histologic evidence of esophagitis. 15 of the 18 patients (83.3%) without endoscopic and histologic abnormalities in the esophagus had scintigraphic evidence of reflux. The present study strongly supports the clinical significance of scintigraphy in GER disease and confirms that esophageal biopsy specimens increase the sensitivity of endoscopic evaluation. 31 refs.

  4. Scintigraphic demonstration of acute myocardial infarcts

    International Nuclear Information System (INIS)

    Holman, B.L.; Lesch, M.

    1976-01-01

    The feasibility of acute infarct scintigraphy for the clinical evaluation of patients with known or suspected acute myocardial infarction is established. Further development of this methodologic approach may result in even better agents for the visualization of infarcts. Radiotracers with high affinity for the infarct, rapid blood clearance, and low concentrations in surrounding organs, such as liver and bone, would be more suitable than available radiopharmaceuticals for acute myocardial infarct scintigraphy. Ultimately, labeling these tracers and ultra-short-lived radionuclides will enable rapid sequential imaging to assess changes in the extent of infarction and to determine the efficacy of therapies aimed at limiting infarct size

  5. Exploring the Usefulness of MISR-HR Products to Estimate Maize Crop Extent and Using Field Evidence to Evaluate the Results in South Africa's Free State Province

    Science.gov (United States)

    Verstraete, M. M.; Knox, N. M.; Hunt, L. A.; Kleyn, L.

    2014-12-01

    The MISR instrument on NASA's Terra platform has been operating for almost 15 years. Standard products are generated at a spatial resolution of 1.1 km or coarser, but a recently developed method to re-analyze the Level-1B2 data allows the retrieval of biogeophysical products at the native spatial resolution of the instrument (275 m). This development opens new opportunities to better address issues such as the management of agricultural production and food security. South African maize production is of great economic and social importance, not only nationally, but on the global market too, being one of the top ten maize producing countries. Seasonal maize production statistics are currently based on a combination of field measurements and estimates derived from manually digitizing high resolution imagery from the SPOT satellite. The field measurements are collected using the Producer Independent Crop Estimate System (PICES) developed by Crop Estimates Committee of the Department of Agriculture, Forestry and Fisheries. There is a strong desire to improve the quality of these statistics, to generate those earlier, and to automate the process to encompass larger areas. This paper will explore the feasibility of using the MISR-HR spectral and directional products, combined with the finer spatial resolution and the relatively frequent coverage afforded by that instrument, to address these needs. The study area is based in the Free State, South Africa, one of the primary maize growing areas in the country, and took place during the 2012-2013 summer growing season. The significance of the outcomes will be evaluated in the context of the 14+ years of available MISR data.

  6. /sup 99m/Tc-aminohexylidendiphosphonate and /sup 99/mTc-Pyrophosphate in the scintigraphic diagnosis of experimental cardiomyopathy in dogs

    Energy Technology Data Exchange (ETDEWEB)

    Duska, F; Kafka, P; Mazurova, Y; Hadas, L; Vizda, J; Palicka, V; Grossman, V

    1987-10-01

    Experimental cardiomyopathy was provoked in 24 dogs with high intravenous doses of adrenaline and theophylline. These lesions were studied by means of the new agent /sup 99m/Tc-AHDP and /sup 99m/Tc-PYP in comparison. Cardiomyopathy could be imaged as early as 4 h after the onset of involvement but not later than 7 days. A maximum accumulation occurred in lesions 24 h old, /sup 99m/Tc uptake in the myocardium was graded scintigraphically, /sup 99m/Tc-AHDP was accumulated in the altered myocardium to a greater extent than /sup 99m/Tc-PYP. Scintigraphic findings were in good agreement with plasma levels of creatine-kinase. A comparison with histology demonstrated that the maximum accumulation of radiopharmaceuticals occurred at the time when the development of myocardium involvement reached the stage of myocytolysis.

  7. Scintigraphic appearance of stress-induced trauma of the dorsal cortex of the third metacarpal bone in racing Thoroughbred horses: 121 cases (1978-1986)

    International Nuclear Information System (INIS)

    Koblik, P.D.; Hornof, W.J.; Seeherman, H.J.

    1988-01-01

    Review of 121 bone scintigrams obtained on racing Thoroughbred horses with clinical histories indicative of forelimb lameness revealed 3 scintigraphic patterns of stress-induced trauma to the dorsal cortex of the third metacarpal bone: (1) focal, intense uptake associated with recent stress fracture; (2) regional uptake of varying intensity or a mixed pattern of uptake associated with chronic stress fracture; and (3) diffuse, mild to moderate uptake associated with periostitis (bucked shins). The latter scintigraphic pattern appeared to be an exaggerated manifestation of the normal remodeling process evident in immature horses (2 to 3 years old). Scintigraphy was most helpful in identifying radiographically occult stress fractures, determining the extent of cortical involvement before surgical intervention in cases of chronic stress fractures, and monitoring the fracture healing process

  8. Extent and Area of Swidden in Montane Mainland Southeast Asia: Estimation by Multi-Step Thresholds with Landsat-8 OLI Data

    Directory of Open Access Journals (Sweden)

    Peng Li

    2016-01-01

    Full Text Available Information on the distribution, area and extent of swidden agriculture landscape is necessary for implementing the program of Reducing Emissions from Deforestation and Forest Degradation (REDD, biodiversity conservation and local livelihood improvement. To our knowledge, explicit spatial maps and accurate area data on swidden agriculture remain surprisingly lacking. However, this traditional farming practice has been transforming into other profit-driven land use, like tree plantations and permanent cash agriculture. Swidden agriculture is characterized by a rotational and dynamic nature of agroforestry, with land cover changing from natural forests, newly-cleared swiddens to different-aged fallows. The Operational Land Imager (OLI onboard the Landsat-8 satellite has visible, near-infrared and shortwave infrared bands, which are sensitive to the changes in vegetation cover, land surface moisture content and soil exposure, and therefore, four vegetation indices (VIs were calculated, including the Normalized Difference Vegetation Index (NDVI, the Normalized Difference Moisture Index (NDMI, the Normalized Burn Ratio (NBR and the Soil Adjusted Vegetation Index (SAVI. In this study, we developed a multi-step threshold approach that uses a combination of thresholds of four VIs and local elevation range (LER and applied it to detect and map newly-opened swiddens and different-aged fallows using OLI imagery acquired between 2013 and 2015. The resultant Landsat-derived swidden agriculture maps have high accuracy with an overall accuracy of 86.9% and a Kappa coefficient of 0.864. The results of this study indicated that the Landsat-based multi-step threshold algorithms could potentially be applied to monitor the long-term change pattern of swidden agriculture in montane mainland Southeast Asia since the late 1980s and also in other tropical regions, like insular Southeast Asia, South Asia, Latin America and Central Africa, where swidden agriculture is

  9. The effect of extent of site investigation on the estimation of radiological performance and its relevance to the proposed Rock Characterisation Facility at Sellafield

    International Nuclear Information System (INIS)

    Mackay, R.

    1996-01-01

    Proof of Evidence is given by an expert witness on behalf of Greenpeace Ltd as part of their submission to a Planning Inquiry in 1995 hearing the application of UK Nirex Ltd for permission to construct an underground Rock Characterisation Facility (RCF) at a site near Sellafield. The RCF is part of an investigation by Nirex into a suitable site for the disposal of radioactive waste. The evidence concerns the necessity of establishing an adequate hydrogeological model of the site in advance of the construction of the RCF in order to estimate its radiological performance. This detailed examination of Nirex's approach concludes that it is not apparent that a method for demonstrating the adequacy of the conceptual hydrogeological model has been clearly and openly stated so that it may be agreed in advance of construction with an appropriate authority. (1 figure; 1 table, 12 references). (UK)

  10. Using GIS mapping of the extent of nearshore rocky reefs to estimate the abundance and reproductive output of important fishery species.

    Directory of Open Access Journals (Sweden)

    Jeremy T Claisse

    Full Text Available Kelp Bass (Paralabrax clathratus and California Sheephead (Semicossyphus pulcher are economically and ecologically valuable rocky reef fishes in southern California, making them likely indicator species for evaluating resource management actions. Multiple spatial datasets, aerial and satellite photography, underwater observations and expert judgment were used to produce a comprehensive map of nearshore natural rocky reef habitat for the Santa Monica Bay region (California, USA. It was then used to examine the relative contribution of individual reefs to a regional estimate of abundance and reproductive potential of the focal species. For the reefs surveyed for fishes (i.e. 18 out of the 22 in the region, comprising 82% the natural rocky reef habitat 30% was produced from a relatively small proportion of the regional reef area (c. 10%. Natural nearshore rocky reefs make up only 11% of the area in the newly designated MPAs in this region, but results provide some optimism that regional fisheries could benefit through an increase in overall reproductive output, if adequate increases in size structure of targeted species are realized.

  11. Scintigraphic examinations after stent implantation in central airways

    International Nuclear Information System (INIS)

    Richter, W.S.; Kettner, B.I.; Munz, D.L.

    1998-01-01

    Endotracheal and endobronchial stent implantation has been developed as an effective treatment of benign and malignant airway stenosis and of tracheo- or bronchoesophageal fistulas. The selection of the stent type depends on the kind and site of disease. Chest X-ray and bronchoscopy are the procedures of choice for monitoring of stent position, structure, and function. However, with scintigraphic methods the effects of stent implantation on pulmonary ventilation and perfusion can be assessed non-invasively. The validation of the effect of a stent implantation on mucociliary and tussive clearance remains to be elucidated. (orig.) [de

  12. Hyper-functioning Thyroid Nodule with Scintigraphic Owl's Eye Appearance

    International Nuclear Information System (INIS)

    Al-Kordi, R.S.; Elgazzar, A.H.

    2006-01-01

    Hyper-functioning thyroid nodules may produce various scintigraphic appearances on thyroid scans. Autonomously hyper functioning thyroid nodules invariably demonstrate degenerative changes. These changes may give rise to central or less commonly peripheral photopenic areas on a thyroid scan within otherwise a hot nodule. In this report we present a case of hyper functioning autonomous nodule with peripheral degeneration and residual central functioning tissue giving the appearance of an owl's eye. Although rare, this pattern can be seen in a variety of benign and malignant thyroid conditions. (author)

  13. Differential diagnosis of scintigraphic brain centres by 75Se selenite

    International Nuclear Information System (INIS)

    Bestagno, M.; Garraffa, V.; Rembado, R.; Guerra, U.

    1975-01-01

    Since standard brain scintigraphy with sup(99m)Tc is not always adequate for a satisfactory differential diagnosis of the radioactive foci detected, the possibilities of 75 Se sodium selenite were investigated. It was observed that in centres due to a vascular lesion the selenite concentration is always low, rising steeply in neoplasmic foci. The 75 Se-selenite scintigraphic method is considered highly valid, complementing that of sup(99m)Tc when this latter is unsuitable for diagnosis of the nature of cerebral foci [fr

  14. Scintigraphic colonic transit study in children with chronic constipation

    International Nuclear Information System (INIS)

    Yano, Tsunehiro; Uemura, Sadashige; Nakaoka, Tatsuo; Nakagawa, Yoshikiyo; Tanimoto, Terutaka; Sone, Teruki

    2008-01-01

    Chronic constipation can be caused either by slow colonic transit or by functional fecal retention. The treatment strategy for chronic constipation should be based on its etiology. Scintigraphic colonic transit study (SCTS) is useful for dividing the cause of the constipation into slow colonic transit and functional fecal retention. SCTS is also useful for judging the therapeutic effect and postoperative intestinal motility of Hirschsprung's disease, anorectal molformation, and others. As SCTS is a safe, simple, and painless examination, it is one of the most important examinations in evaluating chronic constipation. (author)

  15. Scintigraphic test of gastric emptying and motility: preliminary results in patients with chronic gastritis

    Energy Technology Data Exchange (ETDEWEB)

    Hausmann, T. [Abt. Nuklearmedizin und Spezielle Biophysik, Medizinische Hochschule Hannover (Germany); Mueller-Schauenburg, W. [Abt. Nuklearmedizin, Univ. Tuebingen (Germany); Goeke, M. [Abt. Gastroenterologie und Hepatologie, Medizinische Hochschule Hannover (Germany); Luebeck, M. [Abt. Nuklearmedizin, Univ.-Krankenhaus Eppendorf, Hamburg (Germany); Gratz, K.F. [Abt. Nuklearmedizin und Spezielle Biophysik, Medizinische Hochschule Hannover (Germany); Meier, P. [Abt. Gastroenterologie und Hepatologie, Medizinische Hochschule Hannover (Germany); Manns, M. [Abt. Gastroenterologie und Hepatologie, Medizinische Hochschule Hannover (Germany); Hundeshagen, H. [Abt. Nuklearmedizin und Spezielle Biophysik, Medizinische Hochschule Hannover (Germany)

    1995-11-01

    To record gastric peristalsis using a conventional scintigraphic gastric emptying test the frame rate was increased to 1 frame per 3 s at 10, 30, and 50 min postprandially. The gastric contraction frequency was obtained from the first harmonic of a Fourier transform of a gastric region of interest (ROI) curve. The propagation of gastric contractions was better revealed from computed functional images of the phase and amplitude distribution as compared with the multiple scintigraphic images. The maximal count-rate changes per pixel were calculated as an estimate of the most prominent regional contractile activity of the gastric wall. Among 12 patients with chronic gastritis the group with more severe dyspeptic complaints (n = 6) had significantly higher count-rate changes per pixel when compared with the group with minor complaints (20.0, 21.1 and 14.2 vs 12.9, 12.0, and 10.4 counts/pixel X s at 10, 30, and 50 min. respectively; p < 0.05). The mean half-times of gastric emptying (61, SD 11 vs 54, SD 13 min) and the mean gastric contraction frequencies (2.99, SD 0.19; 3.09, SD 0.33; 3.07, SD 0.10 vs 3.15, SD 0.15; 3.17, SD 0.13; 3.23, SD 0.20 cycles/min at 10, 30, and 50 min, respectively) did not show significant differences between both groups. Our preliminary results agree with the hypothesis of the occurrence of more powerful, nonexpulsive gastric-wall contractions in patients with more severe dyspeptic complaints. Hence, additional quantification of gastric motility allowed a more detailed evaluation of gastric-motor-activity disorders that were for so long not accessible to conventional gastric-emptying tests. (orig.)

  16. Scintigraphic test of gastric emptying and motility: preliminary results in patients with chronic gastritis

    International Nuclear Information System (INIS)

    Hausmann, T.; Mueller-Schauenburg, W.; Goeke, M.; Luebeck, M.; Gratz, K.F.; Meier, P.; Manns, M.; Hundeshagen, H.

    1995-01-01

    To record gastric peristalsis using a conventional scintigraphic gastric emptying test the frame rate was increased to 1 frame per 3 s at 10, 30, and 50 min postprandially. The gastric contraction frequency was obtained from the first harmonic of a Fourier transform of a gastric region of interest (ROI) curve. The propagation of gastric contractions was better revealed from computed functional images of the phase and amplitude distribution as compared with the multiple scintigraphic images. The maximal count-rate changes per pixel were calculated as an estimate of the most prominent regional contractile activity of the gastric wall. Among 12 patients with chronic gastritis the group with more severe dyspeptic complaints (n = 6) had significantly higher count-rate changes per pixel when compared with the group with minor complaints (20.0, 21.1 and 14.2 vs 12.9, 12.0, and 10.4 counts/pixel X s at 10, 30, and 50 min. respectively; p < 0.05). The mean half-times of gastric emptying (61, SD 11 vs 54, SD 13 min) and the mean gastric contraction frequencies (2.99, SD 0.19; 3.09, SD 0.33; 3.07, SD 0.10 vs 3.15, SD 0.15; 3.17, SD 0.13; 3.23, SD 0.20 cycles/min at 10, 30, and 50 min, respectively) did not show significant differences between both groups. Our preliminary results agree with the hypothesis of the occurrence of more powerful, nonexpulsive gastric-wall contractions in patients with more severe dyspeptic complaints. Hence, additional quantification of gastric motility allowed a more detailed evaluation of gastric-motor-activity disorders that were for so long not accessible to conventional gastric-emptying tests. (orig.)

  17. Scintigraphic study of gastric emptying with colloidal tin

    International Nuclear Information System (INIS)

    Rodríguez Paleo, Lester; Nuez Vilar, Maricela; Machado Lois, Marisel; López González, María Karla; Torres Leyva, Oscar; Izquierdo Izquierdo, Yimel; García González, Idelsy; Conesa Gonzalez, Ana Ibis

    2016-01-01

    Gastroparesis is defined as a delay in gastric emptying in the absence of mechanical obstruction, associated with symptoms such as nausea and / or vomiting, feeling of postprandial gastric fullness, early satiety or epigastric pain for more than 3 months. The gold standard in the diagnosis of delayed gastric emptying scintigraphy is gastric emptying and radiopharmaceutical has been used more 99m Tc-sulfur colloid not available in the country. In order to evaluate the usefulness of colloidal tin in the scintigraphic gastric emptying study, a descriptive study was conducted in 64 patients over 18 years using as radiopharmaceutical 99m Tc-Sn colloid. 31% of patients had symptoms. The emptying time was normal in 50 cases and the association of gastroparesis symptoms was observed in 20 (15 diabetic and 5 non-diabetic), 9 patients had a delayed emptying, but reported no symptoms. Gastroparesis was more frequent in women than in men (35% versus 21%). 21% of patients had a moderate delayed gastric emptying. Conclusions: The results obtained with 99m Tc-Sn colloid are comparable to those reported by other authors using 99m Tc-SC in the scintigraphic assessment of gastric emptying. (author)

  18. Scintigraphic portrayal of β receptors in the heart

    International Nuclear Information System (INIS)

    Sisson, J.C.; Wieland, D.M.; Koeppe, R.A.; Normolle, D.; Frey, K.A.; Bolgos, G.; Johnson, J.; Van Dort, M.E.; Gildersleeve, D.L.

    1991-01-01

    Myocardial β adrenergic receptors play important roles in physiology and disease, but the receptors have not before been portrayed. The β antagonist, iodocyanopindolol (ICYP), was used to develop a scintigraphic method for depicting the receptors in the living heart. Labeled with 125I, ICYP bound firmly to β receptors in the rat heart; the data conformed to a mathematical model. In vivo saturation kinetics indicated binding sites with two affinities. Inhibition of ICYP binding by beta antagonists of different potency and different selectivity for β-1 and β-2 receptors produced the expected pharmacologic effects. Inhibition by lipophilic and hydrophilic antagonists gave no evidence that ICYP was appreciably bound to internalized receptors. Fractional binding by tracer quantities of (-) ICYP and ± ICYP demonstrated stereospecificity. Labeled with 123I, ICYP bound to the hearts of intact dogs so that scintigraphic tomographs depicted ventricular myocardium. Small doses of beta antagonists selectively reduced the binding of ICYP to lung enabling better visualization of the heart. Thus, 123I-ICYP appears to portray the beta receptors in the living heart, and the characteristics of binding permit the development of mathematical models and lay the basis for quantifying this receptor binding

  19. Acute rhabdomyolysis of the soleus muscle induced by a lightning strike: magnetic resonance and scintigraphic findings

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Naofumi; Inaoka, Tsutomu; Shuke, Noriyuki; Takahashi, Koji; Aburano, Tamio [Asahikawa Medical College, Department of Radiology, Asahikawa (Japan); Chisato, Naoyuki; Go, Kazutomo [Asahikawa Medical College, Department of Emergency Medicine, Asahikawa (Japan); Nochi, Hitoshi [Asahikawa Medical College, Department of Orthopaedic Surgery, Asahikawa (Japan)

    2007-07-15

    Among natural disasters, a lightning strike is a rare but potentially life-threatening phenomenon. If victims survive a cardiac arrest due to instantaneous passage of an exceptionally high voltage electric charge through the whole body, they may be afflicted with various complications such as muscle necrosis resulting in acute renal failure. In this article, we report a case of a 54-year-old man with acute rhabdomyolysis of the left soleus muscle associated with a lightning strike. T2-weighted and short-tau inversion recovery MR images showed a high signal intensity in the left soleus muscle. A whole-body bone scintigram showed abnormal uptakes in the left soleus muscle and the dorsal aspect of the left foot. MR and scintigraphic evaluations were very useful in depicting the site and extent of muscle damage. Since the patient showed a surprisingly high level of serum creatine kinase, the added information was very valuable for determining the patient's management. (orig.)

  20. Preliminary results on scintigraphic evaluation of malignant external otitis

    International Nuclear Information System (INIS)

    Malamitsi, J.; Maragoudakis, P.; Papafragou, K.; Koukouliou, V.; Kalatzis, Y.; Adamopoulos, G.; Proukakis, C.

    1993-01-01

    Malignant external otitis (MEO) is a potentially fatal otitis occurring in diabetic and immunosuppressed patients, which may cause cranial nerve palsies and massive thrombophlebitis of the brain. We studied five diabetic patients with the clinical diagnosis of external otitis who were suspected of having MEO and one diabetic patient presumed cured from MEO. All of them underwent methylene diphosphonate, nanocolloid and gallium single-photon emission tomography studies with quantitative analysis on the basis of regions of interest and count profile curves. This combined assessment helped us to diagnose and follow-up soft tissue and temporal bone infection, especially in the case of transsphenoidal extension of the disease, since conventional radiology and computed tomography were of no particular help. On the basis of these results, we consider scintigraphic demonstration of skull base infection as a fourth criterion of MEO given that the classical Chandler's triad (diabetes, granuloma, and Pseudomonas aeruginosa) is not always present. (orig.)

  1. Scintigraphic findings in amoebic abscess of the liver

    International Nuclear Information System (INIS)

    Buenemann, H.; Petersen, F.; Mohr, W.

    1976-01-01

    The accuracy, size, localization and course of liver scans of solitary or multiple amoebic liver abscesses was evaluated in 52 patients. The scintigraphic data were correlated with the clinical symptoms. In 47 of the 52 patients it was possible to demonstrate the liver abscess on the scintigram; the right lobe of the liver was involved more frequently than would have been expected simply on the basis of its volume. In most of the patients investigated the abscesses were solitary and in only 28% it was possible to recognise two or three abscesses occurring simultaneously. Follow-up examinations showed rapid diminution in the size of the abscess during medical treatment, but complete return to normal during the first six months occured in only 17% of cases. The results are discussed. (orig.) [de

  2. Contribution to scintigraphic study of pulmonary ventilation using 133Xe

    International Nuclear Information System (INIS)

    Chareyron, R.P.

    1975-01-01

    A technique of regional lung function study, using 133 Xe, is described (instrumentation, procedure, results). A gamma-camera is used for this investigation, its main advantages are as follows. The picture is smaller than the one produced by a scanner, but is obtained more quickly. The gamma-camera equipped with a data processing unit is able to visualize areas of interest and to provide quantitative informations. Two parameters are studied. The first one is Xenon washout speed expressed in (ml/mn/cm 3 ) which gives an exact value of pulmonary ventilation. The latter is retention. This parameter is of interest because retention is more easy to evaluate than washout speed, and is able to quantify what is suggested by scintigraphic pictures. The technique has proven to be valuable in differentiating chronic bronchitis from post-bronchitic emphysema [fr

  3. A simple scintigraphic method for continuous monitoring of gastric emptying

    Energy Technology Data Exchange (ETDEWEB)

    Lipp, R.W.; Hammer, H.F.; Schnedl, W.; Dobnig, H.; Passath, A.; Leb, G.; Krejs, G.J. (Graz Univ. (Austria). Div. of Nuclear Medicine and Endocrinology)

    1993-03-01

    A new and simple scintigraphic method for the measurement of gastric emptying was developed and validated. The test meal consists of 200 g potato mash mixed with 0.5 g Dowex 2X8 particles (mesh 20-50) labelled with 37 MBq (1 mCi) technetium-99m. After ingestion of the meal, sequential dynamic 15-s anteroposterior exposures in the supine position are obtained for 90 min. A second recording sequence of 20 min is added after a 30-min interval. The results can be displayed as immediate cine-replay, as time-activity diagrams and/or as acitivty retention values. Complicated mathematical fittings are not necessary. The method lends itself equally to the testing of in- and outpatients. (orig.).

  4. Sjoegren's syndrome. A functional scintigraphic study of salivary glands

    International Nuclear Information System (INIS)

    Arrago, J.P.; Rain, J.D.; Rocher, F.; Vigneron, N.; Pecking, A.; Najean, Y.

    1984-01-01

    One-hundred and twenty patients with sicca syndrome, connective tissue disease or chronic graft-versus-host disease were investigated in the Saint-Louis Hospital Department of Nuclear Medicine. Technetium scanning of the salivary glands was performed in all patients. The results of the scintigraphic study were closely correlated with clinical and histological data in patients with Sjoegren's syndrome. This method, which accurately quantifies the salivary function without danger nor discomfort to the patients, has a number of advantages: (a) it is sensitive enough to detect minimal salivary gland dysfunction; (b) it differentiates between parotid gland and submandibular gland involvement demonstrates assymetry in pathological processes; (c) it helps in following up patients with Sjoegren's disease and in assessing the results of immunosuppressive or anti-inflammatory treatment [fr

  5. Clinical, radiographic and scintigraphic aspects of the trapeziometacarpal osteoarthritis

    International Nuclear Information System (INIS)

    Kaziyama, Helena Hideko Seguchi

    1996-01-01

    Trapeziometacarpal osteoarthritis occurs mainly in women during the menopausal period. It is related to manual activities and is usually bilateral. The onset is insidious and the evolution is slow and progressive. It is characterized by of strength and pain in the basis of the thumb resulting in limitation of the use and function of the hand. The diagnosis of this condition is based on the physical examination. The manouver of compression axial-rotation of the trapezimetacarpal joint is a common positive finding. Typical findings of osteoarthritis are present in the radiological studies. Scintigraphic images have a predictive value. The early diagnosis is important to avoid the risk factors and to prevent disabilities of the hand. (author)

  6. Scintigraphic measurement of colonic transit in patients with idiopathic constipation

    International Nuclear Information System (INIS)

    Yoon, K. H.; Kim, C. K.

    1999-01-01

    To evaluate usefulness of scintigraphic measurement of total and regional colonic transit in patients with idiopathic constipation. 25 patients who were complained chronic constipation underwent scintigraphic measurement of the total and regional colon transit. Of them 10 patients were diagnosed as idiopathic constipation, none of whom had evidence of abnormal function of the pelvic floor. Ten healthy volunteers were also studied. 67 Gallium-labelled Amberlite resin particles were ingested in a coated capsule with methacrylate that dispersed in the ileocecal region. Images were obtained using a gamma camera at regular intervals for the 2, 4, 8, 24, and 48 hours after the initial counting of the radioactivity in the cecum. We determined the geometric center in four regions of interest in the colon (ascending, transverse, descending, and rectosigmoid). Ten patients with colonic inertia showed significant retention of solid residue in the ascending and transverse colon over a 48-hour period. The median values for the healthy subjects at 2, 4, 8, and 24, and 48 hours were 1.44±0.2 (midway through ascending), 1.71±0.45 (midway through transverse), 2.64±0.95 (midway through descending), 3.94±0.89 (midway through rectosigmoid), and 4.52±0.76 (midway through the stool compartment). On the contrary, the values of ten patients with colonic inertia were 1.0±0.0 (midway through ascending), 1.0±0.0 (midway through ascending). 1.02 ±0.06 (midway through ascending), 1.70±0.36 (midway through transverse), and 2.33±0.31(midway through descending) at the same time (p<0.001). In patients with idiopathic constipation is characterized by exaggerated reservoir factions of the ascending and transverse colons. Scintigraphy using 67 Gallium-labelled pellets seems to be a useful tool to demonstrate the delayed colonic transit in patients with colonic inertia

  7. Scintigraphic visualization of bacterial translocation in experimental strangulated intestinal obstruction

    International Nuclear Information System (INIS)

    Galeev, Yu.M.; Popov, M.V.; Salato, O.V.; Lishmanov, Yu.B.; Grigorev, E.G.; Aparcin, K.A.

    2009-01-01

    The purpose of this study was to obtain scintigraphic images depicting translocation of 99m Tc-labelled Escherichia coli bacteria through the intestinal barrier and to quantify this process using methods of nuclear medicine. Thirty male Wistar rats (including 20 rats with modelled strangulated intestinal obstruction and 10 healthy rats) were used for bacterial scintigraphy. 99m Tc-labelled E. coli bacteria ( 99m Ts-E. coli) with an activity of 7.4-11.1 MBq were administered into a section of the small intestine. Scintigraphic visualization of bacterial translocation into organs and tissues of laboratory animals was recorded in dynamic (240 min) and static (15 min) modes. The number of labelled bacteria, which migrated through the intestinal barrier, was quantified by calculating the translocation index (TI). Control indicated no translocation of 99m Ts-E. coli administered into the intestine through the parietes of the small intestine's distal part in healthy animals. Animals with strangulated obstruction demonstrated different migration strength and routes of labelled bacteria from strangulated and superior to strangulation sections of the small intestine. 99m Ts-E. coli migrated from the strangulated loop into the peritoneal cavity later causing systemic bacteraemia through peritoneal resorption. The section of the small intestine, which was superior to the strangulation, demonstrated migration of labelled bacteria first into the portal and then into the systemic circulation. The strangulated section of the small intestine was the main source of bacteria dissemination since the number of labelled bacteria, which migrated from this section significantly, exceeded that of the area superior to the strangulation section of the small intestine (p = 0.0003). Bacterial scintigraphy demonstrated the possibility of visualizing migration routes of labelled bacteria and quantifying their translocation through the intestinal barrier. This approach to study bacterial

  8. Scintigraphic measurement of colonic transit in patients with idiopathic constipation

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, K. H.; Kim, C. K. [College of Medicine, Wonkwang Univ., Iksan (Korea, Republic of)

    1999-07-01

    To evaluate usefulness of scintigraphic measurement of total and regional colonic transit in patients with idiopathic constipation. 25 patients who were complained chronic constipation underwent scintigraphic measurement of the total and regional colon transit. Of them 10 patients were diagnosed as idiopathic constipation, none of whom had evidence of abnormal function of the pelvic floor. Ten healthy volunteers were also studied. 67 Gallium-labelled Amberlite resin particles were ingested in a coated capsule with methacrylate that dispersed in the ileocecal region. Images were obtained using a gamma camera at regular intervals for the 2, 4, 8, 24, and 48 hours after the initial counting of the radioactivity in the cecum. We determined the geometric center in four regions of interest in the colon (ascending, transverse, descending, and rectosigmoid). Ten patients with colonic inertia showed significant retention of solid residue in the ascending and transverse colon over a 48-hour period. The median values for the healthy subjects at 2, 4, 8, and 24, and 48 hours were 1.44{+-}0.2 (midway through ascending), 1.71{+-}0.45 (midway through transverse), 2.64{+-}0.95 (midway through descending), 3.94{+-}0.89 (midway through rectosigmoid), and 4.52{+-}0.76 (midway through the stool compartment). On the contrary, the values of ten patients with colonic inertia were 1.0{+-}0.0 (midway through ascending), 1.0{+-}0.0 (midway through ascending). 1.02 {+-}0.06 (midway through ascending), 1.70{+-}0.36 (midway through transverse), and 2.33{+-}0.31(midway through descending) at the same time (p<0.001). In patients with idiopathic constipation is characterized by exaggerated reservoir factions of the ascending and transverse colons. Scintigraphy using 67 Gallium-labelled pellets seems to be a useful tool to demonstrate the delayed colonic transit in patients with colonic inertia.

  9. An unusual scintigraphic pattern in sickle cell patients

    International Nuclear Information System (INIS)

    Glaser, A.M.; Chen, D.C.P.; Siegel, M.E.; Norris, S.L.; Haywood, L.J.

    1989-01-01

    We reviewed the nuclear medicine files of all patients enrolled in the sickle cell disease clinic who had had scans performed within the previous 5 years. We specifically looked for patterns of tracer uptake in these scans that would correlate with the severe anemia and consequent bone marrow hyperactivity of sickle cell patients. Thirty-three patients were included (21 men and 12 women) with a mean age of 26.8 years (range 17-48 years). The appearance of each of these patients' most recent scans was examined in the areas of the distal femurs, the proximal tibias and the distal tibias; a distinct triangular shaped pattern of increased activity was identified in these areas in a majority of patients. Thirty-three patients without sickle cell disease served as age-matched controls. This pattern was seen in 65.1% (95 out of 146 images) of the sickle cell patients' delayed images and 80.4% (82 out of 102 images) of their blood pool images. In contrast, the control patients demonstrated the triangular pattern in none of their blood pool studies (0%) and only 10.9% of their delayed bone images (P<0.001). The mean age of sickle cell patients with this pattern is 25.6 years which was significantly lower than that of those without this pattern (mean=37.5 years, P<0.05). Given the high prevalence of this unique scintigraphic pattern in a group of patients with known accelerated bone marrow function, these findings may be scintigraphic evidence of bone marrow expansion. The patient's age appears to be an important factor in visualization of this pattern. (orig.)

  10. Scintigraphic aspect of liver in hepatitis. [/sup 198/Au-radiocolloid

    Energy Technology Data Exchange (ETDEWEB)

    Silva, W M; Medeiros, M [Hospital dos Servidores do Estado, Rio de Janeiro (Brazil). Servico de Medicina Nuclear

    1976-01-01

    A series of scintigraphs was made in a group of 15 patients with viral hepatitis, and compared with biochemical tests. Although in some patients the last biochemical tests were only slightly elevated, and in others entirely normal, they all continued to show abnormal scintigraphs with a mottled aspect and splenic uptake. It is supposed that some sequellae remain in the hepatic tissue even though the patient responds well in clinical and laboratory tests.

  11. In vitro evaluation, biodistribution and scintigraphic imaging in mice of radiolabeled anthrax toxins

    International Nuclear Information System (INIS)

    Dadachova, Ekaterina; Rivera, Johanna; Revskaya, Ekaterina; Nakouzi, Antonio; Cahill, Sean M.; Blumenstein, Michael; Xiao, Hui; Rykunov, Dmitry; Casadevall, Arturo

    2008-01-01

    Introduction: There is a lot of interest towards creating therapies and vaccines for Bacillus anthracis, a bacterium which causes anthrax in humans and which spores can be made into potent biological weapons. Systemic injection of lethal factor (LF), edema factor (EF) and protective antigen (PA) in mice produces toxicity, and this protocol is commonly used to investigate the efficacy of specific antibodies in passive protection and vaccine studies. Availability of toxins labeled with imageable radioisotopes would allow to demonstrate their tissue distribution after intravenous injection at toxin concentration that are below pharmacologically significant to avoid masking by toxic effects. Methods: LF, EF and PA were radiolabeled with 188 Re and 99m Tc, and their performance in vitro was evaluated by macrophages and Chinese hamster ovary cells toxicity assays and by binding to macrophages. Scintigraphic imaging and biodistribution of intravenously (IV) injected 99m Tc-and 123 I-labeled toxins was performed in BALB/c mice. Results: Radiolabeled toxins preserved their biological activity. Scatchard-type analysis of the binding of radiolabeled PA to the J774.16 macrophage-like cells revealed 6.6x10 4 binding sites per cell with a dissociation constant of 6.7 nM. Comparative scintigraphic imaging of mice injected intravenously with either 99m Tc-or 123 I-labeled PA, EF and LF toxins demonstrated similar biodistribution patterns with early localization of radioactivity in the liver, spleen, intestines and excretion through kidneys. The finding of renal excretion shortly after IV injection strongly suggests that toxins are rapidly degraded which could contribute to the variability of mouse toxigenic assays. Biodistribution studies confirmed that all three toxins concentrated in the liver and the presence of high levels of radioactivity again implied rapid degradation in vivo. Conclusions: The availability of 188 Re and 99m Tc-labeled PA, LF and EF toxins allowed us to

  12. 3D segmentation of scintigraphic images with validation on realistic GATE simulations

    International Nuclear Information System (INIS)

    Burg, Samuel

    2011-01-01

    The objective of this thesis was to propose a new 3D segmentation method for scintigraphic imaging. The first part of the work was to simulate 3D volumes with known ground truth in order to validate a segmentation method over other. Monte-Carlo simulations were performed using the GATE software (Geant4 Application for Emission Tomography). For this, we characterized and modeled the gamma camera 'γ Imager' Biospace"T"M by comparing each measurement from a simulated acquisition to his real equivalent. The 'low level' segmentation tool that we have developed is based on a modeling of the levels of the image by probabilistic mixtures. Parameters estimation is done by an SEM algorithm (Stochastic Expectation Maximization). The 3D volume segmentation is achieved by an ICM algorithm (Iterative Conditional Mode). We compared the segmentation based on Gaussian and Poisson mixtures to segmentation by thresholding on the simulated volumes. This showed the relevance of the segmentations obtained using probabilistic mixtures, especially those obtained with Poisson mixtures. Those one has been used to segment real "1"8FDG PET images of the brain and to compute descriptive statistics of the different tissues. In order to obtain a 'high level' segmentation method and find anatomical structures (necrotic part or active part of a tumor, for example), we proposed a process based on the point processes formalism. A feasibility study has yielded very encouraging results. (author) [fr

  13. Quantification analysis of the expression of tumor-associated proteins in serum samples from patients with ovarian cancer and those with other tumor location. Possibilities of their use in the diagnosis and estimation of the extent of a tumorous process

    Directory of Open Access Journals (Sweden)

    T. S. Bobrova

    2012-01-01

    Full Text Available The specific features of the expression of tumor-associated proteins (TAP were immunologically studied in the sera of patients with ovarian cancer (OC and other tumor location by means of immune sera (As or monoclonal antibodies (MAb to find out whether they could be used to diagnose and estimate the extent of a tumorous process.MAb 1 (to HEp-2 cell membrane proteins, larynx cancer, Ac4 (to a pool of two ovarian cystadenocarcinomas, and MAb 3 (to affinity-pu- rified proteins of the apparently intact human gastric mucosa were used to examine the sera of patients with OC and other tumor location and positive responsiveness was detected in 82, ~100, and 77 % of cases, respectively. The differences in the expression of TAP in the patients versus healthy donors were shown to be statistically significant (p = 0.0001; p = 0.015; p = 0.01, respectively.The sensitivity of quantifying ELISA in detecting TAP was 78 and 85 % in patients with Stages I–II and III–IV OC, respectively; ~100 and 89 % in patients with breast cancer and in those with gastrointestinal tract cancer, respectively; and 60 and 14 % in patients with lymphopro- liferative diseases and healthy donors, respectively. Comparison of TAP detection rates in the authors’ test systems with multiplex testing with a biochip array of 12 tumor markers has shown that these test systems are at the world standard level.

  14. Scintigraphic evaluation of traumatic splenic lesions in children

    International Nuclear Information System (INIS)

    Erasmie, U.; Mortensson, W.; Persson, U.; Laennergren, K.; St. Goerans Children's Hospital, Stockholm

    1988-01-01

    Ninety-eight children with recent blunt abdominal trauma which initially evoked clinical suspicion of splenic injury were examined with colloid scintigraphy of the spleen and the liver using multiple imaging views and with abdominal survey. Nineteen children were, in addition, examined with tomographic scintigraphy. The clinical findings and the course of the disorder were reanalysed. Scintigraphy indicated splenic injury in 56 children and hepatic injury in another 5 children. The left lateral and the left oblique were the optimum imaging views for detecting splenic ruptures. Tomographic scintigraphy did not improve the diagnostic yield. Abdominal survey failed to indicate almost every second case of splenic rupture and provided no additional information of significance. The clinical review agreed with the scintigraphic diagnosis of splenic lesions but, in addition, it suggested possible splenic lesions in another 10 children with normal scintigraphy. This discrepancy cannot be explained as surgery was not employed; the occurrence of splenic lesions too small to become detectable at scintigraphy or to provoke clinically evident symptoms may be supposed. (orig.)

  15. Association of bone scintigraphic abnormalities with knee malalignment and pain.

    Science.gov (United States)

    Kraus, V B; McDaniel, G; Worrell, T W; Feng, S; Vail, T P; Varju, G; Coleman, R E

    2009-11-01

    The information content of knee bone scintigraphy was evaluated, including pattern, localisation and intensity of retention relative to radiographic features of knee osteoarthritis, knee alignment and knee symptoms. A total of 308 knees (159 subjects) with symptomatic and radiographic knee osteoarthritis of at least one knee was assessed by late-phase (99m)Technetium methylene disphosphonate bone scintigraph, fixed-flexion knee radiograph, full limb radiograph for knee alignment and for self-reported knee symptom severity. Generalised linear models were used to control for within-subject correlation of knee data. The compartmental localisation (medial vs lateral) and intensity of knee bone scan retention were associated with the pattern (varus vs valgus) (p<0.001) and severity (p<0.001) of knee malalignment and localisation and severity of radiographic osteoarthritis (p<0.001). Bone scan agent retention in the tibiofemoral, but not patellofemoral, compartment was associated with severity of knee symptoms (p<0.001) and persisted after adjusting for radiographic osteoarthritis (p<0.001). To the authors' knowledge, this is the first study describing a relationship between knee malalignment, joint symptom severity and compartment-specific abnormalities by bone scintigraphy. This work demonstrates that bone scintigraphy is a sensitive and quantitative indicator of symptomatic knee osteoarthritis. Used selectively, bone scintigraphy is a dynamic imaging modality that holds great promise as a clinical trial screening tool and outcome measure.

  16. Pasteurized intercalary autogenous bone graft: radiographic and scintigraphic features

    International Nuclear Information System (INIS)

    Ehara, Shigeru; Tamakawa, Yoshiharu; Nishida, Jun; Shiraishi, Hideo

    2000-01-01

    Objective. Pasteurized autogenous bone graft sterilized at a low temperature (60 C) is one option for reconstruction after resection of bone and soft tissue tumors. The purpose of this investigation was to assess the normal and abnormal radiographic and scintigraphic findings of pasteurized intercalary autogenous bone graft after resection of bone and soft tissue sarcomas.Design. This was a retrospective evaluation of the radiography and bone scintigraphy findings in patients after treatment of bone and soft tissue sarcomas using an intercalary pasteurized autogenous bone graft.Patients. Among 10 consecutive patients, eight had intercalary grafts, and they constitute the subjects of this study. All available radiography and bone scintigraphy findings were reviewed for the healing process and the possibility of complications.Results and conclusions. Healing and incorporation of the graft were observed in five patients during the follow-up, but the other three did not heal satisfactorily. Rapid incorporation of pasteurized autogenous bone graft can be demonstrated by means of radiography and bone scintigraphy. (orig.)

  17. Scintigraphic evaluation of Zenker's diverticulum

    Energy Technology Data Exchange (ETDEWEB)

    Valenza, Venanzio; Perotti, Germano; Di Giuda, Daniela [Institute of Nuclear Medicine, Policlinico A. Gemelli, Catholic University of Sacred Heart, Largo Gemelli 8, 00168, Rome (Italy); Castrucci, Gioacchino [Department of Surgery, Bel Colle Hospital, Viterbo (Italy); Celi, Giuseppe; Restaino, Gennaro [Institute of Radiology, Catholic University of Sacred Heart, Rome (Italy)

    2003-12-01

    Zenker's diverticulum (ZD) is a rare pathology, with a prevalence of between 0.01% and 0.11%. Definitive diagnosis of ZD can be accomplished by contrast radiographic examination (barium oesophagogram, BE); oesophageal manometry (ME) is recommended mainly for those patients suffering from dysphagia and/or gastro-oesophageal reflux. The aims of the present study were to assess whether oropharyngo-oesophageal scintigraphy (OPES) is able (a) to visualise ZD and (2) to demonstrate the corresponding alteration in the swallowing phases. We studied 16 patients (nine male, seven female, mean age 67.4 years), and 17 healthy volunteers (ten male, seven female, mean age 53 years) as a control group. All the patients underwent ME, BE and OPES. Nine patients underwent surgery and six of them were re-evaluated after 6 months. We administered 10 ml of water with 37 MBq of technetium-99m colloid through a straw, acquiring 480 sequential images (0.125 s/frame for a total of 60 s) with the patient standing in front of the gamma camera in the 80 right anterior oblique position. Two static images were performed at the end of the dynamic phase, before and after ingestion of 100 ml of unlabelled water to evaluate the presence of inflammation (persistence of radioactivity in the diverticulum or oesophagus). Study of the sequential scintigraphic images and time-activity curves permitted both qualitative (diverticulum visualisation, multiple deglutitions, reflux, presence of inflammation) and quantitative analyses [oral, pharyngeal and oesophageal transit times and retention indexes, tracheal aspiration percentage] of swallowing disorders. OPES showed a good correlation with the results of other diagnostic techniques usually performed in patients with this pathology, and especially with ME in the evaluation of oropharyngeal phase disorders. Furthermore, OPES is a sensitive and simple technique that is well tolerated and entails a low irradiation dose for patients. (orig.)

  18. Scintigraphic evaluation of the esophageal transit in patients with polymyositis

    International Nuclear Information System (INIS)

    Viterbo, B.G.; Moriguchi, S.M.; Rocha, O.M.; Henry, M.A.C.A.

    2002-01-01

    Aim: To evaluate the esophageal function of patients with polymyositis. Materials and Methods: Nine patients with polymyositis were evaluated, 8 female and 1 male. The ages ranged from 20 to 65 years. Seventeen healthy volunteers (4 female and 13 male) were also evaluated as control group. The median age was 28 years (20 to 41). All patients and controls were submitted to the esophageal scintigraphy performed after the oral ingestion of 37 MBq of stannous colloidal labeled with 99m Tc and diluted in 10 ml of water. The dynamic study was acquired on the supine position, 1 frame/0.5 sec., during 50 sec with a large-field-of-view gamma-camera. Time-activity curves were generated from ROIs positioned over the three portions of the esophagus (upper, middle and distal). The radiotracer retention (RR) after 15 seconds of the peak of radioactivity on the whole esophagus was calculated as a percentage. The pattern of the time-activity curves was classified as normal, as hypomotility or as a mixed pattern, with associated dysmotility. Non-parametric statistical analysis was made with the Mann-Whitney test and the significance level was set at 5%. Results: All the patients with polymyositis presented esophageal motor alterations on the esophageal scintigraphy. Eight (88.9%) patients revealed a mixed pattern at the three segments of the esophagus and 1 (11.1%) patient presented hypomotility at the middle and distal segments. All the healthy volunteers showed normal results at the scintigraphic study. The mean RR of the patients with polymyositis was 69.1% and 4.4% on the control group (P<0.0001). Conclusion: The esophageal transit scintigraphy is a sensitive and useful method to evaluate functional disorders of the esophagus of patients with polymyositis

  19. Scintigraphic detection of thrombi using indium-111-labeled autologous platelets

    International Nuclear Information System (INIS)

    Ikeoka, Kiyomitsu; Todo, Yasuhiro; Konishiike, Atsushi; Fujisue, Ryu; Ohyanagi, Mitsumasa; Yasutomi, Nagao; Tanimoto, Masaho; Kawai, Yoshitaka; Iwasaki, Tadaaki

    1985-01-01

    Intracardiac and arterial thrombi were examined by scintigraphy using In-111-oxine labeled autologous platelets. 1. In 22 cases of myocardial infarction including six with ventricular aneurysms, four had positive findings of thrombi on imaging and detected also by echocardiography. All four had ventricular aneurysms. The so-called ''moya-moya'' echoes (fuzzy echoes) were demonstrated in two of these four cases. 2. We encountered two cases with positive findings on imaging in 13 with mitral valve disease. These two had systemic embolic episodes after scintigraphic examination. ''Moya-moya'' echoes were detected in the left atrial cavity in four with negative findings on imaging. 3. Positive images were obtained in two of three with acute arterial occlusive disease, and in both cases platelet deposition was observed in the proximal site of obstruction. Though thrombectomy was performed for one of these two cases, no thrombus was detected at the site of platelet deposition. After one month, re-examination revealed only negative findings in all sites in both these patients. 4. In the six cases of aortic aneurysm, three had platelet deposition within their aneurysms, and surgery was performed for these positive cases, but one of them had no thrombus. 5. Positive images were obtained in only one of seven patients with chronic arterial occlusive disease. 6. Coagulation tests and platelet studies were investigated for patients with positive or negative platelet scans. Only the data of the thrombo-test showed a significant difference (97 +- 9 % vs 23 +- 7 %, p < 0.001). Three cases of positive imaging became negative after anticoagulant therapy. 7. We tried ECT for eight cases 24 hours after injection of In-111-oxine labeled platelets. Three cases showed clear images of thrombi, while the planar images could not detect them at an early stage. Therefore, we propose that ECT can be a useful technique for diagnosing intracardiac thrombi in early stage. (author)

  20. Scintigraphic method for evaluating reductions in local blood volumes in human extremities

    DEFF Research Database (Denmark)

    Blønd, L; Madsen, Jan Lysgård

    2000-01-01

    in the experiment. Evaluation of one versus two scintigraphic projections, trials for assessment of the reproducibility, a comparison of the scintigraphic method with a water-plethysmographic method and registration of the fractional reduction in blood volume caused by exsanguination as a result of simple elevation......% in the lower limb experiment and 6% in the upper limb experiment. We found a significant relation (r = 0.42, p = 0.018) between the results obtained by the scintigraphic method and the plethysmographic method. In fractions, a mean reduction in blood volume of 0.49+0.14 (2 SD) was found after 1 min of elevation......We introduce a new method for evaluating reductions in local blood volumes in extremities, based on the combined use of autologue injection of 99mTc-radiolabelled erythrocytes and clamping of the limb blood flow by the use of a tourniquet. Twenty-two healthy male volunteers participated...

  1. Unusual and subtle scintigraphic findings in the evaluation of the battered child

    International Nuclear Information System (INIS)

    Howard, J.L.; Barron, B.J.; Smith, G.G.

    1988-01-01

    Nuclear medicine imaging plays a key role in the evaluation of skeletal trauma. Recent findings in our department show that diagnoses other than skeletal trauma are often identified by means of subtle and unusual scintigraphic findings. The subject material will place strong emphasis on the less mentioned but often more important visceral and intracranial injury. Specific scintigraphic abnormalities to be demonstrated, with appropriate correlative radiographs, include (1) visceral and soft tissue (eg, duodenal hematoma, splenic laceration, renal contusion, hepatic hematoma, rhabdomyolysis and soft-tissue hematoma); (2) cranial (eg, intracranial bleeding, edema, and infarct, cephalohematoma, skull fracture, and widening of sutures; and (3) skeletal (various subtle abnormalities)

  2. 99m-Tc HMDP bone scintigraphic findings of gouty arthropathy of both hands

    International Nuclear Information System (INIS)

    Shih, Wei-Jen; Domstad, P.A.; Purcell, M.; DeLand, F.H.

    1988-01-01

    The 99m Tc hydroxy methylene diphosphonate scintigraphic findings of both hands are correlated to the radiographic findings in a patient with a 30-year history of gouty arthropathy. Scintigraphic differentiation of the type of arthritis on the basis of uptake pattern is difficult. However, the findings of rheumatoid arthritis are confined to the joints and usually the involvement is symmetrical. With gout there is a tendency toward asymmetrical, bilateral, multifocal joint involvement with areas of intense abnormal uptake; because of the associated soft tissue swelling, the intense uptake usually extends beyond the involved joints. (author)

  3. The scintigraphic reaction pattern of traumatic bone lesions; Das szintigraphische Reaktionsmuster knoecherner Verletzungen

    Energy Technology Data Exchange (ETDEWEB)

    Spitz, J. [Praxis fuer Nuklearmedizin, Staedtisches Klinikum Wiesbaden (Germany)

    1994-12-01

    The indications for bone scintigraphy in traumatology result: 1. Definite exclusion of bone lesions by normal scintigraphic findings (except for the scull). 2. Unclear result of X-ray or a mismatch between clinical investigation and X-ray result. 3. Screening after multiple injury which leads to the detection of an unknown bone lesion in every second patient. 4. Suspicion of a complicated healting course in cases of doubtful X-ray results. 5. The estimation of relative fracture age. This question always rises, if a pre-existing trauma or morphologic changes in X-ray make a clear diagnosis impossible. The additional information gained by bone scintigraphy is in part exclusive and not to be drawn from any other imaging modality. This renders bone scintigraphy to an important tool in the work up of medico-legal questions in traumatology. (orig.) [Deutsch] Aus den speziellen szintigraphischen Eigenschaften knoecherner Verletzungen ergeben sich die Indikationen fuer die Skelettszintigraphie in der Traumatologie: 1. Ausschluss einer ossaeren Laesion durch einen szintigraphischen Normalbefund (bei Einhaltung eines ausreichenden Abstandes zum Trauma bilden nur die Schaedelknochen eine Ausnahme); 2. ein unklarer Roentgenbefund oder eine Diskrepanz zwischen Klinik, Anamnese und Roentgenbild; 3. das Screening nach Polytrauma, das bei jedem zweiten unfallverletzten Patienten eine zusaetzliche, bis dahin noch nicht bekannte und radiologisch dann nachvollziehbare Fraktur nachweist; 4. der Verdacht auf einen gestoerten Heilungsverlauf, soweit die primaer eingesetzte Roentgendiagnostik keine verbindliche Interpretation erlaubt; 5. die Bestimmung des relativen Frakturalters, die von Bedeutung ist, wenn vorbestehende Unfaelle in der Anamnese oder morphologische Veraenderungen die Interpretation des Roentgenbildes beeintraechtigen. Die mit Hilfe der Skelettszintigraphie erhaltenen Informationen sind zum Teil exklusiv und mit keinem anderen bildgebenden Verfahren so einfach zu

  4. Local bone pain and osseous scintigraphic findings in patients with metastatic bone tumor

    International Nuclear Information System (INIS)

    Imaeda, Takeyoshi; Iinuma, Gen; Hirota, Keiichi; Inoue, Akemi; Sone, Yasuhiro; Seki, Matsuzo; Suzuki, Masao; Doi, Hidetaka

    1988-01-01

    Local bone pain and osseous scintigraphic findings were evaluated in patients with cancer of the lung, breast or prostate. (1) In 77-92% out of the patients with local pain, metastatic bone lesions were detected. (2) The sacrum and scapulae were the frequent sites of pain as estimated from the metastatic bone lesions. On the other hand, the incidence of pain was low in the ribs, cervical vertebrae, skull and femurs. (3) When calculated by the weight of red bone marrow, the most likely sites for bone metastases consisted of the scapulae, clavicles, sternum, humeri, ribs and cervical vertebrae, somewhat different from previous reports. Those bones involved were all proximate to the heart. (4) Extensive bone metastases were already detected in more than 50% of patients who complain of pain in the metastatic bone lesion. On the other hand, extensive bone metastases occurred in less than 6% of patients who didn't complain of pain. (5) The appearance of pain in the metastatic bone lesion was earlier in only 3% and was later in 71% than the detection of abnormal radioisotope accumulation on scintigram. (6) Majority of the patients with pain in the metastatic bone lesion showed a high degree of abnormal radioisotope accumulation which measured more than 5 cm in diameter on scintigram. On the other hand, the abnormal radioisotope accumulation in most of patients without pain was mild and mostly measured less than 5 cm in diameter. (7) The positive rate of bone metastasis amounted to 29% by plain X-ray and 41% by local bone pain as compaired to positive bone scintigram. (author)

  5. Local bone pain and osseous scintigraphic findings in patients with metastatic bone tumor

    Energy Technology Data Exchange (ETDEWEB)

    Imaeda, Takeyoshi; Iinuma, Gen; Hirota, Keiichi; Inoue, Akemi; Sone, Yasuhiro; Seki, Matsuzo; Suzuki, Masao; Doi, Hidetaka

    1988-12-01

    Local bone pain and osseous scintigraphic findings were evaluated in patients with cancer of the lung, breast or prostate. (1) In 77-92% out of the patients with local pain, metastatic bone lesions were detected. (2) The sacrum and scapulae were the frequent sites of pain as estimated from the metastatic bone lesions. On the other hand, the incidence of pain was low in the ribs, cervical vertebrae, skull and femurs. (3) When calculated by the weight of red bone marrow, the most likely sites for bone metastases consisted of the scapulae, clavicles, sternum, humeri, ribs and cervical vertebrae, somewhat different from previous reports. Those bones involved were all proximate to the heart. (4) Extensive bone metastases were already detected in more than 50% of patients who complain of pain in the metastatic bone lesion. On the other hand, extensive bone metastases occurred in less than 6% of patients who didn't complain of pain. (5) The appearance of pain in the metastatic bone lesion was earlier in only 3% and was later in 71% than the detection of abnormal radioisotope accumulation on scintigram. (6) Majority of the patients with pain in the metastatic bone lesion showed a high degree of abnormal radioisotope accumulation which measured more than 5 cm in diameter on scintigram. On the other hand, the abnormal radioisotope accumulation in most of patients without pain was mild and mostly measured less than 5 cm in diameter. (7) The positive rate of bone metastasis amounted to 29% by plain X-ray and 41% by local bone pain as compaired to positive bone scintigram.

  6. A comparison of methods of assessment of scintigraphic colon transit.

    Science.gov (United States)

    Freedman, Patricia Noel; Goldberg, Paul A; Fataar, Abdul Basier; Mann, Michael M

    2006-06-01

    There is no standard method of analysis of scintigraphic colonic transit investigation. This study was designed to compare 4 techniques. Sixteen subjects (median age, 37.5 y; range, 21-61 y), who had sustained a spinal cord injury more than a year before the study, were given a pancake labeled with 10-18 MBq of (111)In bound to resin beads to eat. Anterior and posterior images were acquired with a gamma-camera 3 h after the meal and then 3 times a day for the next 4 d. Seven regions of interest, outlining the ascending colon, hepatic flexure, transverse colon, splenic flexure, descending colon, rectosigmoid, and total abdominal activity at each time point, were drawn on the anterior and posterior images. The counts were decay corrected and the geometric mean (GM), for each region, at each time point calculated. The GM was used to calculate the percentage of the initial total abdominal activity in each region, at each time point. Colonic transit was assessed in 4 ways: (a) Three independent nuclear medicine physicians visually assessed transit on the analog images and classified subjects into 5 categories of colonic transit (rapid, intermediate, generalized delay, right-sided delay, or left-sided delay). (b) Parametric images were constructed from the percentage activity in each region at each time point. (c) The arrival and clearance times of the activity in the right and left colon were plotted as time-activity curves. (d) The geometric center of the distribution of the activity was calculated and plotted on a graph versus time. The results of these 4 methods were compared using an agreement matrix. Though simple to perform, the visual assessment was unreliable. The best agreement occurred between the parametric images and the arrival and clearance times of the activity in the right and left colon. The different methods of assessment do not produce uniform results. The best option for evaluating colonic transit appears to be a combination of the analog images

  7. The use of fast digital filters for the processing of scintigraphic pictures

    International Nuclear Information System (INIS)

    Grochulski, W.; Penczek, P.

    1982-01-01

    A brief review of typical methods applied in the development of digital filters for the processing of scintigraphic pictures is given. A simple parametrisation of such filters in the frequency domain is proposed and successfully applied in the case of mathematically simulated IAEA phantoms. The FFT algorithm is used. A possible application of the fast Walsh transform is pointed out. (author)

  8. Scintigraphic detection of gynaecological tumours by sup(99m)Tc-HSA blood pool imaging

    Energy Technology Data Exchange (ETDEWEB)

    Georgiou, E C; Arkas, A Z; Alevizaki, C C; Gnafakis, N [Evangelismos Hospital, Athens (Greece). Dept. of Endocrinology and Radioisotopes; Evangelismos Hospital, Athens (Greece). Gynaecology Clinic)

    1979-12-01

    Three cases of scintigraphic visualization of gynaecological tumours by sup(99m)Tc-HSA blood pool imaging are presented, i.e. one case of fibrothecoma ('cold' area visualization) and two cases of fibromyoma ('hot' area visualization). It is suggested that this technique may be useful in the preoperative evaluation of gynaecological tumours and their vascularity.

  9. Scintigraphic determination of gastrointestinal transit times. A comparison with breath hydrogen and radiologic methods

    DEFF Research Database (Denmark)

    Madsen, J L; Larsen, N E; Hilsted, J

    1991-01-01

    A scintigraphic method for determination of gastrointestinal transit times was compared with the breath hydrogen test and a multiple-bolus, single-radiograph technique. A close temporal association was found between the caecal appearance of radioactivity and the onset of breath hydrogen excretion...... the breath hydrogen concentration profiles....

  10. Differentiated thyroid carcinoma in a scintigraphically hot nodule: diagnosis and interdisciplinary therapeutical approach

    International Nuclear Information System (INIS)

    Stahl, A.; Hess, U.; Langhammer, H.; Harms, J.; Zwicknagl, M.

    2002-01-01

    A hyperfunctioning differentiated thyroid carcinoma is a rare occurrence. Nevertheless, this diagnosis must be considered in a scintigraphically hot nodule if there is a clinical or sonographic suggestion of malignancy. The case of a 57-year old patient with hyperthyreosis and a scintigraphically hot thyroid nodule is presented. Further evaluation led to the diagnosis of a differentiated thyroid carcinoma with extensive lymph node and pulmonary metastases (pT2b, pN1b, pM1). The scintigraphically hot nodule corresponded to the primary tumor, whereas scintigraphic detection of the lymph node metastases was only possible postoperatively. Extensive resection of the lymph node metastases was achieved by the intraoperative application of a gamma probe (2nd operation). This allowed sufficient uptake of radioiodine in the pulmonary metastases for their detection and subsequent devitalization by radioiodine therapy. Complete elimination of all tumor tissue was documented at a control follow-up after six months. Gamma probe-guided surgery may allow for additional removement of non-palpable lymph node metastases. In selected cases this may optimize the surgical results and thereby facilitate the subsequent radioiodine elimination of advanced differentiated thyroid carcinomas. (author)

  11. Diffuse lung uptake (DLU) on Ga-67 scintigraph: Clinical, radiologic and pathologic correlation

    International Nuclear Information System (INIS)

    Sy, W.M.; Seo, I.S.; Vieira, J.; Zaman, M.

    1985-01-01

    Review, analysis and correlation (clinical, radiologic and pathologic) of 29 consecutive adults (16 drug addicts and/or homosexuals) with DLU on Ga-67 scintigraph were made. Diffuse increased uptake of at least 75% of both lungs was considered as DLU. WFOF cameras were used to obtain 24 to 96 hr. scintigraphs after IV injection of 3-5 mCi of Ga-67 citrate. In 26, tissue diagnosis established: pneumocystis carinii (PC) 15, miliary tuberculosis (TB) 3, sarcoidosis (SR) 3, drug-induced toxicity 2, and toxoplasmosis (TX), primary hyperparathyroidism and nonspecific lymphocytic pneumonia-one each. In two with breast and one with esophageal carcinomas, no lung tissue diagnosis was sought. Concurrent chest x-rays were negative in 16, but in 7/16, lung infiltrate was later documented. An average of 31 days elapsed before x-rays became positive in four with PC, 7 days in two with TB, and 22 days in one with TX. In 13, concurrent x-rays showed lung infiltrate, but in 6, only subtle, localized rather than diffuse infiltrate was noted. Fourteen of 29 had at least two Ga-67 studies. In 12 (7 PC, 2 TB, 3 SR) of 14 whose repeat studies showed significant to total disappearance of DLU, all did well clinically. In two whose initial studies were negative or equivocal, they became clinically worse when the repeat study showed DLU. In three others (2 PC, 1 TX) who died, their single studies recorded intense DLU. DLU on gallium scintigraph indicated a variety of pathology. In 55.2%, gallium scintigraph predated x-ray findings by a few days to weeks. In 20.3%, x-ray findings were only subtle or localized. Scintigraphic changes correlated well with the clinical courses in various diseases

  12. Is there a role for scintigraphic imaging of bone manifestations in Gaucher disease? A review of the literature

    International Nuclear Information System (INIS)

    Mikosch, P.; State Hospital Klagenfurt; Kohlfuerst, S.; Gallowitsch, H.J.; Kresnik, E.; Lind, P.; Mehta, A.B.; Hughes, D.A.

    2008-01-01

    Gaucher disease is the most prevalent inherited, lysosomal storage disease and is caused by deficient activity of the enzyme β-glucocerebrosidase. Bone and bone marrow alterations are frequent in the most prevalent non-neuronopathic form of Gaucher disease. Imaging of bone manifestations in Gaucher disease is performed by a variety of imaging methods, conventional X-ray and MRI as the most frequently and most important ones. However, different modalities of scintigraphic imaging have also been used. This article gives an overview on scintigraphic imaging with respect to bone manifestations in Gaucher disease discussing the advantages and limitations of scintigraphic imaging in comparison to other imaging methods. (orig.)

  13. Making the best use of our previous results as a clue for interpreting kinetics of scintigraphic agents

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Sato

    2011-08-01

    Full Text Available Up to now, we have performed scintigraphy with 201-thallium chloride (201-TlCl and 99m-Tc-hexakis-2-methoxy-isobutyl-isonitrile (99m-Tc-MIBI for malignant tumors and lymphoscintigraphy with 99m-Tc-rhenium-colloid (99m-Tc-Re and 99m-Tc-human-serum-albumin-diethylene-triamine-penta-acetic-acid (99m-Tc-HSA-D for lymph node metastasis. In this article, we re-evaluated scintigraphic images retrospectively with a hope that the results might be a clue, even if it is small, for dentists to try to improve the accuracy of diagnosis of malignant tumors. From scintigraphy, we obtained the tumor retention index as a factor to estimate the uptake of radioactive agents in tumor cells. Moreover, we estimated transport proteins of Na+/K+-ATPase and permeability-glycoprotein (P-gp expressed on the cell membrane that might regulate the kinetic condition of radioactive agents. Among the tumor retention index, the transport protein and the histopathologic finding of tumors, there were relatively well correlations. The tumor retention index showed a difference clearly between malignant tumor and benign tumor. The transport protein revealed a distinct expression in accordance with the malignancy of tumor, and the uptake clearly depended upon the expression of transport protein. Moreover, the lymph node metastasis was detected well by lymphoscintigraphy with 99m-Tc-Re and 99m-Tc-HSA-D.

  14. Pharyngeal transit time measured by scintigraphic and biomagnetic method; Tempo de transito faringeano medido atraves dos metodos cintilografico e biomagnetico

    Energy Technology Data Exchange (ETDEWEB)

    Miquelin, C.A.; Braga, F.J.H.N.; Baffa, O. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras. Dept. de Fisica; Dantas, R.O.; Oliveira, R.B. [Faculdade de Medicina de Ribeirao Preto, SP (Brazil)

    1996-12-31

    A comparative evaluation between scintigraphic and biomagnetic method to measure the pharyngeal transit is presented. Three volunteers have been studied. The aliment (yogurt) was labeled with {sup 9}9{sup m} Technetium for the scintigraphic test and with ferrite for the biomagnetic one. The preliminary results indicate a difference between the values obtained, probably due to the biomagnetic detector resolution 3 refs., 2 figs., 1 tab.

  15. The extent of forest in dryland biomes

    Science.gov (United States)

    Jean-Francois Bastin; Nora Berrahmouni; Alan Grainger; Danae Maniatis; Danilo Mollicone; Rebecca Moore; Chiara Patriarca; Nicolas Picard; Ben Sparrow; Elena Maria Abraham; Kamel Aloui; Ayhan Atesoglu; Fabio Attore; Caglar Bassullu; Adia Bey; Monica Garzuglia; Luis G. GarcÌa-Montero; Nikee Groot; Greg Guerin; Lars Laestadius; Andrew J. Lowe; Bako Mamane; Giulio Marchi; Paul Patterson; Marcelo Rezende; Stefano Ricci; Ignacio Salcedo; Alfonso Sanchez-Paus Diaz; Fred Stolle; Venera Surappaeva; Rene Castro

    2017-01-01

    Dryland biomes cover two-fifths of Earth’s land surface, but their forest area is poorly known. Here, we report an estimate of global forest extent in dryland biomes, based on analyzing more than 210,000 0.5-hectare sample plots through a photo-interpretation approach using large databases of satellite imagery at (i) very high spatial resolution and (ii) very high...

  16. Scintigraphic small intestinal transit time and defaecography in patients with J-pouch

    DEFF Research Database (Denmark)

    Kjær, Mie Dilling; Simonsen, Jane Angel; Hvidsten, Svend

    2015-01-01

    Objective methods for examination of pouch function are warranted for a better understanding of the functional result and treatment of dysfunction. The objective of this study was to evaluate the results of scintigraphic intestinal transit time and defaecography compared to the results of pouch...... function, mucosal condition and a questionnaire on quality of life (QoL). This cross-sectional study included 21 patients. Scintigraphic transit time and defaecography was determined with the use of Tc-99m. Pouch function was assessed by number of bowel movements, pouch volume, and continence. Pouch...... mucosal condition was evaluated by endoscopy and histology. Median transit time was 189 min (105–365). Median ejection fraction at defaecography (EF) was 49% (3–77) and 62% (17–98) after first and second defecation. Median pouch volume was 223 mL (100–360). A median daily stool frequency of nine (4...

  17. Evaluation of radionuclide calibrators and scintigraphic cameras used in nuclear medicine in the Sergipe

    International Nuclear Information System (INIS)

    Lima Ferreira, F.C.; Nascimento Souza, D. do

    2008-01-01

    A quality control program to nuclear medicine services concerns the verification of the efficiency of equipment used to diagnosis and treatment, allow the professional improvement. In this study were assessed the performance of two radionuclide calibrators (activimeters) and of two scintigraphic cameras employed in nuclear medicine in the state of Sergipe, Brazil, according to regulation CNEN -NN-3.05. Additionally, to the radionuclide calibrators it was established a nd characterized an intercomparison of activities measured by different practitioners from standard samples of sealed radioactive sources of 133 Ba and 57 Co. The evaluation of this manufacture object was made thought quality control tests on scintigraphic cameras, such as: test of spatial resolution, tomographic resolution and linearity. The results of the quality control tests were satisfactory and they one can be used as parameter in future evaluations. (author)

  18. Scintigraphic diagnosis of stress-induced incomplete fractures of the proximal tibia

    International Nuclear Information System (INIS)

    Collier, B.D.; Johnson, R.P.; Carrera, G.F.; Akhtar, K.; Isitman, A.T.

    1984-01-01

    Incomplete stress fractures of the proximal tibial diaphysis can be diagnosed by bone scintigraphy. The scintigraphic appearance of incomplete rather than complete tibial stress fractures is apparently reported for the first time in this article. With no treatment other than restricted activity, this injury heals rapidly and completely in 4 to 6 weeks. The major threat to the patient's welfare is unfounded suspicion of tumor or infection which may lead to biopsy or inappropriate therapy

  19. Evolution of scintigraphic renal lesions in children after an episode of acute pyelonephritis

    International Nuclear Information System (INIS)

    Donoso, Gilda; Lagos, Elizabeth; Rosati, Pia; Hevia, Pilar; Cuevas, Karen; Lobo, Gabriel; Perez, Andres; Gutierrez, Daniela

    2012-01-01

    Background: Abnormal Dimercaptosuccinic acid (DMSA) renal scintigraphy performed six months after an acute pyelonephritis (AP) is generally interpreted as scarring. Aim: To perform a follow up of childhood patients showing scintigraphic renal lesions during the acute phase of pyelonephritis (within 7 days from the beginning of fever). Material and Methods: A scintigraphic control was carried out at 5-7 months and, in case of persistent lesions, an additional late scintigraphy at 10-13 months. All patients were followed clinically for one year and those with a relapse of urinary tract infection were excluded from the study. Results: Eighty five patients with a median age of 8 months were included. Among these, the first scintigraphic control was normal in 59 (69%) and abnormal in 26 patients (31%). In five of these 26 patients (5/26:19%-5/85:6%), a considerable regression of the lesions was obvious on the early control, and normalized completely on the late control. When expressing the results in kidney units, 107 showed lesions during the acute phase of infection; 69% was normal at the early control. Thirty three showed lesions persisting at the early control (31%) and 7 out of these 33 (21%) became normal on the late control (7/107: 7%). In total, 25% of the children included in the study (24% of the kidney units) remained with renal sequelae one year after the initial episode of AP. Conclusions: The persistence of scintigraphic lesions six months after an episode of AP, does not necessarily correspond to permanent scars, since normalization can sometimes be observed on late controls

  20. Evaluation of quatitative scintigraphic method in diagnosis of esophagic involvement of Progressive Systemic Sclerosis

    International Nuclear Information System (INIS)

    Von Muehlen, C.A.

    1985-01-01

    Twenty patients with Progressive Systemic Sclerosis are studied by scintigraphic methodology. The esophageal transit method is used for liquid and solid meals. The results are compared with the ones of a control group, without or not gastrintestinal problems but without autoimmune diasese. 99 sup(m)Tc-sulfurcolloid is used as labelling compound. The studies were done in supine and orthostatical position. (M.A.C.) [pt

  1. Temporal contrast enhancement and parametric imaging for the visualisation of time patterns in dynamic scintigraphic imaging

    International Nuclear Information System (INIS)

    Deconinck, F.; Bossuyt, A.; Lepoudre, R.

    1982-01-01

    Image contrast, photon noise and sampling frequency limit the visual extraction of relevant temporal information in scintigraphic image series. When the Unitation is mainly due to low temporal contrast, temporal contrast enhancement will strongly improve the perceptibility of time patterns in the series. When the limitation is due to photon noise and limited temporal sampling, parametric imaging by means of the Hadamard transform can visualise temporal patterns. (WU)

  2. Scintigraphic measurements of the heart-blood-pool in dialyzed chronic uremic patients

    International Nuclear Information System (INIS)

    Nagy, E.S.; Nemessanyi, Z.; Narai, G.; Szegedi Orvostudomanyi Egyetem; Szegedi Orvostudomanyi Egyetem

    1976-01-01

    The authors have carried out scintigraphic measurements of the heart in order to diagnose the presence of an exudative pericarditis 50 times in 26 dialyzed uremic patients. Within the one year's observation 13 patients had an exudative pericarditis from the beginning on. In 8 cases a regression of the exudation could be observed. The examination has a low risk for the patient and is suitable to demonstrate clinically relevant pericardial liquid accumulation. (orig.) [de

  3. Scintigraphic Methods to Evaluate Alterations of Gastric and Esophageal Functions in Female Obesity

    Directory of Open Access Journals (Sweden)

    Özgür Ömür

    2014-02-01

    Full Text Available Objective: Altered gastrointestinal function has frequently been observed in obese patients. The aim of this study was to investigate the frequency of gastro-esophageal reflux (GER and to determine the alterations of gastric emptying and esophageal transit by scintigraphic methods in obese patients. Methods: Scintigraphic studies of 50 obese female non-diabetic patients who had not received any treatment for weight control were retrospectively reviewed. Mean Body Mass Index (BMI was 34.96±3.04 kg/m² (range:32-39 kg/m². All subjects were submitted to scintigraphic evaluation of esophageal transit, gastro-esophageal reflux, gastric emptying and presence of Helicobacter pylori infection. The data of obese patients were compared with those of sex-age matched 30 non-obese cases who were selected from our clinical archive. Results: In obese group, seventeen (34% patients were found to be GER positive scintigraphically; mean gastric emptying time (t½ was 59.18±30.8 min and the mean esophageal transit time was 8.9±7.2 s. Frequency of positive GER scintigraphy and the mean value of esophageal transit time were significantly higher in obese patients than non-obese control subjects. Gastric emptying time and esophageal transit time values were significantly longer in GER positive obese patients than GER negative ones. There was no statistically significant difference in the frequency of positive C14 urea breath test between obese and non-obese subjects and there were also no statistically significant correlations between BMI, GER, esophageal transit time and gastric emptying time. Conclusion: In our study, 42 of the 50 obese patients had esophago-gastric motility alterations. The significance of these alterations in obesity is not fully understood, but it is believed that these changes could be because of potential contributing factors in the development or maintenance of obesity or changes in eating habits

  4. Hepatic Scintigraphic Findings of Budd-Chiari Syndrome due to Inferior Vena Caval Obstruction

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung Hoon; Chung, Soo Kyo; Byun, Jae Young; Lee, Sung Yong; Shinn, Kyung Sub; Kim, Choon Yul; Bahk, Yong Whee [Catholic University College of Medicine, Seoul (Korea, Republic of)

    1988-03-15

    Budd-Chiari syndrome (BCS) is a rare clinical entity characterized by post-sinusoidal portal hypertension caused by the obstruction to the hepatic vein outflow. The diagnosis is suggested by hepatic scintigraphy and is usually confirmed by hepatic venography, inferior vena cavography and biopsy. The scintigraphic finding of BCS caused by the obstruction of main hepatic vein has been reported to consist typically of hypertrophy of the caudate lobe with increased radionuclide accumulation. Such a typical finding has been accounted for by the fact that the venous outflow from the caudate lobe is preserved when the main hepatic vein is obstructed. But usually, the hepatic venous outflow from the caudate lobe is also obstructed in BCS due to inferior vena caval obstruction. So hepatic scintigraphic findings of BCS due to inferior vena caval obstruction show different findings as compared with the BCS due to hepatic vein obstruction. We evaluate the hepatic scintigrams of the 13 cases of BCS due to inferior vena caval obstruction and review the literatures. The results are as follows: 1) We cannot observe the caudate lobe hypertrophy with increased uptake, which is known as a classic finding in BCS due to hepatic vein obstruction. 2) The most prominent hepatic scintigraphic findings of BCS are nonhomogenous uptake in the liver with extrahepatic uptake in the all cases. 3) We can see cold areas at the superior aspect of right hepatic lobe in 7 cases (54%). This is a useful finding suggesting BCS due to inferior vena caval obstruction.

  5. Scintigraphic diagnosis of experimentally induced pericarditis in dogs using 99sup(m)Tc-labelled pyrophosphate

    International Nuclear Information System (INIS)

    Duska, F.; Novak, J.; Vizda, J.; Kubizek, J.; Simon, J.; Veverkova, O.; Karlova Universita, Hradec Kralove

    1981-01-01

    In the present paper the possibilities of scintigraphic diagnosis of experimental pericarditis are discussed. Pericarditis was induced by either talc or formaldehyde intrapericardially. In all animals the administration of talc as well as formaldehyde produced inflammatory changes which were more serious after formaldehyde. The scan of the talc pericarditis was carried out on the 7th day after operation and of the formaldehyde pericarditis on the 3rd, 7th and 14th day. No positive scintigraphic finding was made in any of the experimental animals, apart from a massive incorporation in the operation scars. The counting of radioactive impulses after the exstirpation of the tissue samples confirmed the scintigraphic findings. Statistical evaluation did not reveal any essential difference between the accumulation of the radiopharmaceutical into the pericarditis as well as into the pericardial bag in comparison with the control animals. Although our model does not exactly reflect the situation of patients suffering from pericarditis it may be assumed that pyrophosphate scintigraphy is not suitable for the diagnosis of acute pericarditis in clinical practice. (orig.) [de

  6. Gamma scintigraphic analysis of albumin flux in patients with acute respiratory distress syndrome

    International Nuclear Information System (INIS)

    Sugerman, H.J.; Tatum, J.L.; Burke, T.S.; Strash, A.M.; Glauser, F.L.

    1984-01-01

    Computerized gamma-scintigraphy provides a new method for the analysis of albumin flux in patients with pulmonary permeability edema. In this technique, 10 mCi of 99 mTc -tagged human serum albumin is administered and lung:heart radioactivity ratios are determined. This ratio remains constant unless there is a leak of albumin, when a rising ratio with time, called the ''slope index'' (SI), is seen. Thirty-five scintigraphic studies were obtained in 28 patients by means of a portable computerized gamma-camera. Thirteen of these patients had clinical evidence of the acute respiratory distress syndrome (ARDS) and six had or were recovering from left ventricular induced congestive heart failure (CHF). Five of the patients with CHF and pulmonary capillary wedge pressure (PCWP) below 30 mm Hg had normal scintigraphic studies. The patients with ARDS were found to have significantly higher SIs than patients who did not have, or had recovered from, ARDS. Positive SIs were present from 1 to 8 days following the apparent onset of ARDS in seven studies in five patients. Recovery of gas exchange was associated with a return to a normal SI in four patients. In conclusion, computerized gamma-scintigraphy was a sensitive, noninvasive tool for the detection of a pathologic increase in pulmonary protein flux. Positive scintigraphic findings were associated with significantly impaired gas exchange. The method documented that the leak of albumin in patients with ARDS may last for days but resolves with recovery

  7. The 'fragmented' scintigraphic lung pattern in pulmonary lymphangitic carcinomatosis secondary to breast cancer.

    Science.gov (United States)

    Vattimo, A V; Burroni, L; Bertelli, P; Vella, A; Volterrani, D

    1998-01-01

    Pulmonary lymphangitic carcinomatosis (PLC) is an unusual presentation of diffuse infiltrative lung disease. In this report we present two cases secondary to breast cancer; the diagnosis was made by means of transbronchial lung biopsy or postmortem examination. The goal of this study was to analyze the scintigraphic pattern of pulmonary perfusion performed with technetium-99m macroaggregated albumin (99mTc-MAA) in the hope of achieving improved recognition of PLC and its subsequent diagnosis. Upon admission, both patients underwent routine clinical exams followed by chest X-rays. The second patient also underwent CT examination, and both were ultimately examined using pulmonary perfusion scintigraphy with 99mTc-MAA. In the various exams performed, the most reliable and easily identified diagnostic finding turned out to be a characteristic 'fragmented' lung pattern revealed with the perfusion lung scan. Unfortunately, in both cases the patients' conditions rapidly worsened and death occurred shortly following scintigraphy. We were able to conclude that the recognition of the mentioned fragmented scintigraphic lung pattern may be useful in suspected PLC, whereas the nonspecific clinical presentation of this pathology makes diagnosis extremely difficult, with the most significant results being achieved through a comparison of scintigraphic and high resolution CT data.

  8. Experience based on 60 observations of scintigraphic bone exploration using pyrophosphates

    International Nuclear Information System (INIS)

    Mienville, J.-C.

    1975-01-01

    5 to 15 millicuries of technetium 99m-labelled pyrophosphates are injected intraveinously. 3 to 5 hours later, when the blood activity has dropped, the bone uptake is sufficient to give a good scintigraphic image of the skeleton. The skeleton may be explored one segment at a time, using a scanning scintigraph or a scintillation camera, or the whole skeleton front and back may be examined much more quickly with a 'whole-body' device. A study of 60 observations shows the large number of hyperfixations revealed by isotopic explorations in rheumatological diseases. A hyperfixation was observed in almost all bone localities of osteophilic cancers, osteonecrosis, Paget's disease, infections osteo-arthritis and algoneurodystrophy. On the other hand the isotopic test was found to be negative or inefficient in arthroses, osteoporosis and local bone manifestations of Kahler's or Hodgkin's disease. Finally inflammatory arthritis was detectable by scintigraphy in about half the cases studied. In reality a hyperfixation reflects a local rise in the metabolic activity of the bone at the moment of the examination. As a result the scintigraphic images lack specificity. This factor must therefore be accounted for in the patient's records and isotopic results compared with those of clinical and para-clinical examinations [fr

  9. Scintigraphic determination of the effect of metoclopramide and morphine on small intestinal transit time

    Energy Technology Data Exchange (ETDEWEB)

    Prokop, E.K.; Caride, V.J.; Winchenbach, K.; Troncale, F.J.; McCallum, R.W.

    1988-01-01

    To determine if a scintigraphic method could detect pharmacologic changes in small intestinal transit time (SITT), 10 male volunteers were studied at baseline and after intravenously administered metoclopramide (10 mg) and morphine (8 mg). Five of these volunteers were studied with the hydrogen breath test method for comparison. For each of the scintigraphic studies, the volunteers were positioned supine under a large-field-of-view gamma camera after ingesting an isosmotic lactulose solution containing 99mtechnetium-diethylenetriaminepentaacetic acid (DTPA). Data were collected and stored in a computer. Both gastric emptying and SITT were determined. SITT was 81 +/- 11 min (mean +/- S.E.M.; N = 10) during baseline studies, was decreased significantly to 50 +/- 6 min (N = 10; P less than 0.01) after metoclopramide, and was increased significantly to 161 +/- 15 min (N = 8; P less than 0.01) after morphine. Baseline mean values were 86.3 +/- 15 min (N = 15) for the hydrogen breath tests, 47 +/- 8 min (N = 5) for metoclopramide, and 183 +/- 16 min (N = 5) for morphine. For gastric emptying, there was no significant difference in percentage emptying at 1 hr for baseline and metochopramide (82 +/- 5% vs. 88 +/- 4%). Morphine prolonged gastric emptying at 1 hr to 63 +/- 8%. We conclude that the scintigraphic method for measuring SITT permits accurate investigation of the pharmacologic effects on intestinal motility and, in addition, may be a useful research and clinical method for SITT determination.

  10. Scintigraphic anatomy of coronary artery disease in digital thallium-201 myocardial images

    International Nuclear Information System (INIS)

    Wainwright, R.J.

    1981-01-01

    One hundred and eight patients with single and multiple vessel coronary artery disease confirmed by arteriography were evaluated by exercise thallium-201 ( 201 Tl) myocardial scintigraphy to determine the scintigraphic appearances of specific coronary stenoses. In general proximal stenoses caused more widespread, but not necessarily more severe, myocardial tracer deficit, than distal stenoses. In particular, proximal dominant right coronary artery disease was specifically associated with extensive inferior wall tracer deficit in the anterior scintigram, whereas proximal left circumflex disease caused similar tracer depletion best visualised in the left lateral scintigram. A triad of uptake defects was caused by left anterior descending coronary artery disease; one of these defects called 'diagonal window tracer deficit' was the most useful scintigraphic sign distinguishing proximal from distal disease in the left anterior descending coronary artery. Certain scintigraphic patterns of 201 Tl myocardial accumulation appear invaluable in the noninvasive localisation of stenoses within specific coronary arteries and thus may be useful in predicting life-threatening coronary artery disease which should be confirmed by definitive coronary arteriography. The digital 201 Tl myocardial scintigram also provides an independent functional guide to the interpretation of coronary arteriograms and may be helpful in the planning of aortocoronary bypass graft surgery. (author)

  11. Scintigraphic Small Intestinal Transit Time and Defaecography in Patients with J-Pouch

    Directory of Open Access Journals (Sweden)

    Mie Dilling Kjaer

    2015-10-01

    Full Text Available Objective methods for examination of pouch function are warranted for a better understanding of the functional result and treatment of dysfunction. The objective of this study was to evaluate the results of scintigraphic intestinal transit time and defaecography compared to the results of pouch function, mucosal condition and a questionnaire on quality of life (QoL. This cross-sectional study included 21 patients. Scintigraphic transit time and defaecography was determined with the use of Tc-99m. Pouch function was assessed by number of bowel movements, pouch volume, and continence. Pouch mucosal condition was evaluated by endoscopy and histology. Median transit time was 189 min (105–365. Median ejection fraction at defaecography (EF was 49% (3–77 and 62% (17–98 after first and second defecation. Median pouch volume was 223 mL (100–360. A median daily stool frequency of nine (4–25 was reported and three (14% patients suffered from daytime incontinence. No patients had symptomatic or endoscopic pouchitis; however, the histology showed unspecific inflammation in 19 (90% patients. There was no correlation between transit time, evacuation fraction (EF and pouch function in univariate analysis. However, we found a high body mass index (BMI and a low bowel movement frequency to be associated with a longer transit time by multivariate analysis. Scintigraphic determination of transit time and defaecography are feasible methods in patients with ileal pouch anal anastomosis, but the clinical relevance is yet doubtful.

  12. Avascularity of the femoral head following intracapsular fracture: a comparative scintigraphic and bioptic study

    Energy Technology Data Exchange (ETDEWEB)

    Hoilund-Carlsen, P F; Widding, A; Uhrenholdt, A; Christoffersen, P; Grieff, J [Copenhagen Univ. (Denmark)

    1980-03-01

    Bioptic and scintigraphic methods of diagnosing avascular necrosis of the femoral head following intracapsular fracture of the femoral neck were compared. During operative treatment of patients, biospy samples of bone marrow were taken from the femoral head about 2 hours after the intravenous injection of sup(99m)Tc-Sn-pyrophosphate; histological examination of the biopsies were also performed. Scintigrams of the femoral head using sup(99m)Tc-pyrophosphate were performed 2 days, 7 days and 6 weeks post-operatively. The biopsies confirmed no morphological changes being apparent in the first few days. The biopsy samples indicated two groups of patients with either high or low activity in the femoral head. However, it was concluded that the use of bone-seeking radionuclides with this technique might be more reliable. Scintigraphic trends divided the patients into three groups, one with persistently normal, another with varying, and a third with decreased activity in the femoral head. It was concluded that very early scintigraphy is probably not the method of choice since the images were often difficult to interpret. For the present, assessment of the viability of the femoral head should rest upon scintigraphic examinations performed about 6 weeks or 3 months after the injury.

  13. Hepatic Scintigraphic Findings of Budd-Chiari Syndrome due to Inferior Vena Caval Obstruction

    International Nuclear Information System (INIS)

    Kim, Sung Hoon; Chung, Soo Kyo; Byun, Jae Young; Lee, Sung Yong; Shinn, Kyung Sub; Kim, Choon Yul; Bahk, Yong Whee

    1988-01-01

    Budd-Chiari syndrome (BCS) is a rare clinical entity characterized by post-sinusoidal portal hypertension caused by the obstruction to the hepatic vein outflow. The diagnosis is suggested by hepatic scintigraphy and is usually confirmed by hepatic venography, inferior vena cavography and biopsy. The scintigraphic finding of BCS caused by the obstruction of main hepatic vein has been reported to consist typically of hypertrophy of the caudate lobe with increased radionuclide accumulation. Such a typical finding has been accounted for by the fact that the venous outflow from the caudate lobe is preserved when the main hepatic vein is obstructed. But usually, the hepatic venous outflow from the caudate lobe is also obstructed in BCS due to inferior vena caval obstruction. So hepatic scintigraphic findings of BCS due to inferior vena caval obstruction show different findings as compared with the BCS due to hepatic vein obstruction. We evaluate the hepatic scintigrams of the 13 cases of BCS due to inferior vena caval obstruction and review the literatures. The results are as follows: 1) We cannot observe the caudate lobe hypertrophy with increased uptake, which is known as a classic finding in BCS due to hepatic vein obstruction. 2) The most prominent hepatic scintigraphic findings of BCS are nonhomogenous uptake in the liver with extrahepatic uptake in the all cases. 3) We can see cold areas at the superior aspect of right hepatic lobe in 7 cases (54%). This is a useful finding suggesting BCS due to inferior vena caval obstruction.

  14. Tumoral calcinosis: scintigraphic studies of an affected family

    International Nuclear Information System (INIS)

    Balachandran, S.; Abbud, Y.; Prince, M.J.; Chausmer, A.B.

    1980-01-01

    Tumoral calcinosis is a rare, familial ectopic calcification syndrome associated with hyperphosphataemia. A family in which seven of 13 siblings had demonstrable, clinical, radiological and pathological findings of tumoral calcinosis was evaluated. The purposes were to compare the efficacy of bone scintiscans with serum phosphorus determination in detecting subclinical disease early in asymptomatic siblings and to assess therapeutic results in affected family members following initiation of phosphate depletion therapy. History, physical examination, serum calcium, serum phosphorus and bone scintiscans were performed in 12 of 13 siblings. All the affected siblings had markedly elevated serum phosphorus levels and abnormal bone scintiscans while the unaffected siblings had normal serum phosphorus levels and normal bone scintiscans. All the siblings, affected and unaffected, were normocalcaemic. After initiation of phosphate depletion therapy, gross changes in the appearance of lesions were detected on bone scintiscans. Serum phosphorus levels likewise showed a modest decline, although still remaining in the hyperphosphataemic range. In conclusion, bone scintiscans and serum phosphorus determinations are equally sensitive in detecting subclinical disease. However, the scintiscans are helpful in assessing not only the extent of the disease, but also whole-body and regional changes following any therapeutic interventions. (author)

  15. Evaluation by scintigraphic images of musculoskeletal infection with 99mTc ciprofloxacin

    International Nuclear Information System (INIS)

    Casacó, C.A.; Hernández, A.; Perera, A.; Prats, A.; Batista, J.F.; Torres, L.A.; Quesada, R.; Sánchez, Y.; Valladares, L.; Sánchez, E.L.; Marrero, L.O.; Mustelier, E.

    2016-01-01

    Introduction: Infectious diseases present high morbidity and mortality in all countries, especially in the third world. In Cuba between 2005 and 2014, approximately 1.3% of the total deaths were killed. Orthopedic infections are among the most common. The scintigraphic methods currently used are not able to discern between a septic focus and a sterile inflammation. Radiological methods detect a bone infection only when there is significant anatomical damage. Ciprofloxacin as a drug binds and inhibits topoisomerase II or bacterial gyrase DNA. Objective: to evaluate the efficacy of 99m Tc-ciprofloxacin in the detection of osteo-articular bacterial processes. Materials and Methods: An experimental, cross-sectional, cross-sectional study was conducted involving 258 patients with suspected osteoarticular infectious processes. The presence of the lesion and the quantification and intensity of uptake in the foci of infection in images with 99m Tc-MDP (3h post-administration) and 99m Tc-ciprofloxacin (1, 4 and 24h post-administration) were visually determined. Studies of 99m Tc-ciprofloxacin were compared with Culture / Biopsy results. Results: The germ that most frequently appears in infected osteo-articular sites is staphilococcusaureus. No adverse effects were detected in any of the subjects studied. Studies with 99m Tc-MDP allow delineating infected areas but are not specific. 99mTc-ciprofloxacin shows the sites of active osteo-articular bacterial infection and when it is fixed in a septic focus gives intense captures at both 4 and 24 hours. It exhibits a sensitivity similar to 99mTc-MDP, but a significantly higher specificity. Conclusions: Scintigraphic images with 99m Tc-ciprofloxacin show sites of active osteo-articular bacterial infection with a specificity significantly higher than 99m Tc-MDP. The microbiological and scintigraphic results were positive for sepsis in 122 patients out of 219 who were sampled.

  16. Contribution of different scintigraphic techniques to the management of medullary thyroid carcinoma

    International Nuclear Information System (INIS)

    Sandrock, D.; Blossey, H.C.; Steinroeder, M.; Munz, D.L.

    1989-01-01

    We compared three different scintigraphic techniques for the localization of neck recurrences and metastases in seven patients with medullary thyroid carcinoma one month to eight years after the first surgical intervention. Three successive scintigraphic studies were performed in five patients (6 x 3 studies) within two weeks using 201Tl chloride, 111In-labeled F(ab')2 fragments of the anti-carcinoembryonic antigen (anti-CEA) monoclonal antibody (MoAb) BW 431/31, and 131I meta-iodo-benzylguanidine (MIBG). Additionally, 11 studies were performed with the 111In-labeled MoAb fragment BW 431/31 (seven studies) or the 99mTc-labeled intact anti-CEA MoAb BW 431/26 (four studies). The gold standards for classifying scintigraphic results were biopsy, histology, surgery, and cytology. Six regions were classified as positive or negative in each study: thyroid region, four quadrants (lymph node regions) around the thyroid, and the region of the upper mediastinum. Of 36 sites, 201Tl was true positive (TP) in seven sites, false-positive (FP) in one site, true negative (TN) in 22 sites, and false-negative (FN) in six sites, resulting in a sensitivity of 54% and a specificity of 96%. 131I MIBG was TP in four sites, FP in none of the sites, TN in 23 sites, and FN in nine sites, with a sensitivity of 31% and a specificity of 100%. Immunoscintigraphy (102 sites overall) was TP in 16 sites, FP in five sites, TN in 77 sites, and FN in four sites, resulting in a sensitivity of 80% and a specificity of 94%. Immunoscintigraphy with 111In/99mTc anti-CEA F(ab')2 fragment/intact antibody is superior to scintigraphy with 201Tl and 131I MIBG

  17. Scintigraphic images of bacterial infection using aptamers directly labeled with {sup 99m}Tc

    Energy Technology Data Exchange (ETDEWEB)

    Santos, S.R.; Correa, C.R.; Andrade, A.S.R., E-mail: sararoberta7@hotmail.com, E-mail: crisrcorrea@gmail.com, E-mail: antero@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Barros, A.L.B.; Diniz, S.O.F.; Cardoso, V.N., E-mail: brancodebarros@yahoo.com.br, E-mail: valbertcardoso@yahoo.com.br, E-mail: simoneodilia@yahoo.com.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Faculdade de Farmacia. Departamento de Analises Clinicas e Toxicologicas

    2015-07-01

    Staphylococcus aureus is specie of great medical importance and is the most commonly agent found in infections of soft tissues, bone infections and bone prostheses. In this study, aptamers selected to S. aureus were labeled by the direct method with {sup 99m}Tc and used for bacterial infection identification by scintigraphy. The radiolabeled aptamers radiochemical purity and stability were assessed by thin-layer chromatography (TLC). Three groups of Swiss mice (n=6) were used for the scintigraphic imaging studies. The first group was infected intramuscularly in the right thigh with S. aureus, the second group with C. albicans and the third group received zymosan to induce aseptic inflammation. After 24 h, radiolabeled aptamers (18 MBq) were injected by the tail vein. Scintigraphic images were acquired at 1 h and 4 h postinjection. The radiolabeling yield with {sup 99m}Tc was over 90%. The radiolabeled aptamers were stable in 0.9% saline, plasma and cysteine excess. The scintigraphic image profiles showed high uptake in the kidneys and bladder in all groups, indicating a main renal excretion consistent with the hydrophilic nature of the molecule. No accumulation of radioactivity was observed in the thyroid, stomach, liver and spleen, indicating acceptable levels of radiochemical impurities. The group infected with S. aureus showed a visible uptake in the infected right thigh at 1 h post-injection. For the control groups (C. albicans and zymosan) visible differences between the right and left thighs were not observed. The radiolabeled aptamers were able to distinguish aseptic inflammation from bacterial infection and bacterial from fungal infection. (author)

  18. Role of intensity transformation function for enhancement of bone scintigraphic images.

    Science.gov (United States)

    Pandey, Anil Kumar; Dhiman, Vishali; Sharma, Akshima; ArunRaj, Sreedharan Thankarajan; Baghel, Vivek; Patel, Chetan; Sharma, Param Dev; Bal, Chandrasekhar; Kumar, Rakesh

    2018-03-29

    The bone scintigraphic image might exceed the dynamic range (the ratio between the highest and the lowest brightness a monitor is capable of displaying) of display monitor. In this case, a high intensity area, and loss of the details of other structures in the displayed image makes the clinical interpretation a challenging task. We have investigated the role of intensity transformation function for enhancement of these types of images. Methods: Forty high dynamic range bone scintigraphic images were processed using intensity transformation (IT) function. The IT function has two parameters: threshold and slope. Keeping the threshold equal to mean counts of the image, the value of slope was varied from 1 to 20. In-house application program written in MATLAB R2013b was used to process images. Twenty output images corresponding to one input image were visually inspected by two experienced nuclear medicine (NM) physicians to select diagnostic quality images, and from their selection the standardized slope (value of slope parameter) that produced maximum numbers of diagnostic images was determined. They also rated the image quality of input and output images (at standardized slope) on scale 1 to 5 [where 1 is for poor and 5 if for the excellent diagnostic quality]. Student's t-test was used to test the significance of difference between the mean image quality score assigned to input and processed images at significance level α = 0.05. Results: The application of IT functions with standardized parameters significantly improved the quality of high dynamic range bone scintigraphic images ( P enhancement. Copyright © 2018 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

  19. Scintigraphic images of bacterial infection using aptamers directly labeled with 99mTc

    International Nuclear Information System (INIS)

    Santos, S.R.; Correa, C.R.; Andrade, A.S.R.; Barros, A.L.B.; Diniz, S.O.F.; Cardoso, V.N.

    2015-01-01

    Staphylococcus aureus is specie of great medical importance and is the most commonly agent found in infections of soft tissues, bone infections and bone prostheses. In this study, aptamers selected to S. aureus were labeled by the direct method with 99m Tc and used for bacterial infection identification by scintigraphy. The radiolabeled aptamers radiochemical purity and stability were assessed by thin-layer chromatography (TLC). Three groups of Swiss mice (n=6) were used for the scintigraphic imaging studies. The first group was infected intramuscularly in the right thigh with S. aureus, the second group with C. albicans and the third group received zymosan to induce aseptic inflammation. After 24 h, radiolabeled aptamers (18 MBq) were injected by the tail vein. Scintigraphic images were acquired at 1 h and 4 h postinjection. The radiolabeling yield with 99m Tc was over 90%. The radiolabeled aptamers were stable in 0.9% saline, plasma and cysteine excess. The scintigraphic image profiles showed high uptake in the kidneys and bladder in all groups, indicating a main renal excretion consistent with the hydrophilic nature of the molecule. No accumulation of radioactivity was observed in the thyroid, stomach, liver and spleen, indicating acceptable levels of radiochemical impurities. The group infected with S. aureus showed a visible uptake in the infected right thigh at 1 h post-injection. For the control groups (C. albicans and zymosan) visible differences between the right and left thighs were not observed. The radiolabeled aptamers were able to distinguish aseptic inflammation from bacterial infection and bacterial from fungal infection. (author)

  20. Principle and preliminary results of the whole-body scintigraphic unit Omniview

    International Nuclear Information System (INIS)

    Methlin, G.; Jung, G.M.; Gerard, G.

    The Picker Company has recently launched a system adapted to its Dynacamera for the production of whole-body scintigraphs. For the last few months the radioisotopes service of the Strasbourg Anti-Cancer Centre has been in possession of such a system, intended mainly for systematic research on metastases, especially of the bone, and on the degree of extension of tumours. On the basis of the short experience so far acquired the report is limited to an outline of the working principle of this device, the presentation of preliminary documents and a few critical remarks summing up first impressions [fr

  1. Scintigraphic hepatobiliary function studies in newborn infants to diagnose biliary hypoplasia or atresia

    International Nuclear Information System (INIS)

    Askari-Sabi, Z.

    1987-01-01

    The results obtained from scintigraphic hepatobiliary function studies, intraoperative cholangiography and histological examinations in a total of 17 infants suspected of having biliary atresia were compared and analysed with reference to the clinical signs and symptoms observed. In most cases, the individual diagnostic procedures led to consistent findings, even though there were some variations in the clinical picture. Patient outcome is largely determined by the site of atresia, due to which fact surgical correction should be carried out as soon as possible, in any case before the 8th week post partum. (TRV) [de

  2. Scintigraphic localization of a disseminated malignant pheochromocytoma with the use of 131I-meta-iodobenzylguanidine

    International Nuclear Information System (INIS)

    Troncone, L.; Maini, L.M.; Rufini, V.; Bonifazi, N.; De Rosa, G.; Corsello, S.M.; Mattei, O.

    1984-01-01

    Preliminary clinical studies with 131 I-meta-iodo-benzylguanidine, a newly synthesized radiopharmaceutical and guanethidine analog capable of imaging the adrenal medulla, have led to the identification, of a case of disseminated malignant pheochromocytoma with the localization of brain and bone metastases. The result is of particular interest as the symptomatology in this case appeared rather equivocal and various investigations had led to a completely different diagnosis. This new scintigraphic technique has proved to be safe, specific and noninvasive, and it may have a clinical application as a complementary or alternative technique to conventional diagnostic tests. (orig.)

  3. Scintigraphic measurements of gastric emptying corrected for differences in tissue attenuation

    Energy Technology Data Exchange (ETDEWEB)

    Lauritzen, J.B.; Hoejgaard, L.; Uhrenholdt, A. (Copenhagen Univ. (Denmark). Hvidovre Hospital)

    1983-10-01

    In order to evaluate the importance of variations in tissue attenuation in scintigraphic measurements of gastric emptying, both in vivo and in vitro measurements of count rates from an encapsulated sup(99m)Tc dose were performed in different parts of the stomach. The obtained individual tissue correction factors were applied in the calculation of gastric emptying rates by gamma camera in healthy volunteers. The results showed that the anterior gamma camera scan without correction for differences in tissue attenuation underestimated the gastric emptying rate by 11% if the results were expressed as percentage meal emptied over 60 minutes.

  4. Scintigraphic and clinical findings in the Standardbred metatarsophalangeal joint: 114 cases (1993-1995)

    International Nuclear Information System (INIS)

    Ross, M.W.

    1998-01-01

    To correlate scintigraphic and clinical findings of the metatarsophalangeal joint (MTPJ) in Standardbreds, radiographic findings in horses with confirmed MTPJ lameness, and determine if stress reaction and more advanced bone remodelling occurred in the MTPJ, medical records of 114 Standardbreds admitted between September 1993 and April 1995 in which bone scintigraphy included standing lateral and plantar views of the metatarsophalangeal joint (MTPJ) were reviewed. Images obtained using a large field of view gamma camera were evaluated visually for location, definition and intensity of increased radioisotope uptake (IRU), which was graded as mild, moderate, or intense. Clinical history and lameness examination findings were recorded and, in horses with documented MTPJ lameness, radiographic examination included the 30 degree (down-angled) dorsolateral 45 degree plantaromedial view thought to be useful in evaluation of the plantarolateral condyle of the third metatarsal bone (MtIII). The most common abnormality, IRU of the plantarolateral aspect of MtIII, was seen in 67 horses, and horses were further classified according to scintigraphic and clinical findings. In 43 horses in which lameness was not localised to the MTPJ, mild (32 horses), moderate (10 horses), and intense (one horse) IRU of MtHII was found. In 24 horses with lameness localised to the MTPJ, moderate (18 horses) and intense (6 horses) IRU was found. Of 18 horses with moderate IRU of MtIII, 9 had radiographic evidence of abnormal bony remodelling of MtIII, whereas 5 of 6 horses with intense IRU had radiographic changes. In 12 horses with MTPJ lameness and radiographic evidence of bony remodelling without fracture, radiographic changes consisted of plantarolateral subchondral radiolucency and sclerosis (7 horses), radiolucency and osteochondrosis (one horse), and plantar MtIII sclerosis without radiolucency (4 horses). In 2 horses with moderate IRU and MTPJ lameness, radiographic evidence of

  5. Scintigraphic study of blood perfusion of the pulmonary artery in pulmonary tuberculosis

    International Nuclear Information System (INIS)

    Certain, D.A.; Brolio, R.; Salomon, G.C.; Carvalho, N.; Barbosa, Z.L.M.

    1972-01-01

    Blood perfusion in the pulmonary artery is studied by pulmonary scintigraphy with macroaggregated albumin 131 I, in 74 cases of pulmonary tuberculosis. Results shown by scintigraphy are compared to those observed in roentgenography and also correlated with the extension and degree of the lesions, and with the presence of associated tuberculosis, considered capable of changing the scintigraphic picture. The reduction of blood flow in the pulmonary artery are observed in cases of infiltrative, fibrotic of caseous lesions, as well as in cases of minor lesions [pt

  6. Scintigraphic study of blood perfusion of the pulmonary artery in pulmonary tuberculosis

    Energy Technology Data Exchange (ETDEWEB)

    Certain, D A; Brolio, R; Salomon, G C [Sao Paulo Univ. (Brazil). Faculdade de Saude Publica; Carvalho, N [Sao Paulo Univ. (Brazil). Centro de Medicina Nuclear; Barbosa, Z L.M. [Associacao dos Sanatorios Populares de Campos do Jordao, Brazil

    1972-10-01

    Blood perfusion in the pulmonary artery is studied by pulmonary scintigraphy with macroaggregated albumin /sup 131/I, in 74 cases of pulmonary tuberculosis. Results shown by scintigraphy are compared to those observed in roentgenography and also correlated with the extension and degree of the lesions, and with the presence of associated tuberculosis, considered capable of changing the scintigraphic picture. The reduction of blood flow in the pulmonary artery are observed in cases of infiltrative, fibrotic of caseous lesions, as well as in cases of minor lesions.

  7. Parallel scintigraphic and echographic studies in patients with miscellaneous andrologic diseases

    International Nuclear Information System (INIS)

    Sultanov, S.; Stanchev, P.; Tsvetkov, D.

    1989-01-01

    The diagnostic possibilities of scintigraphic and echographic methods are compared for diagnostics of varicocele, cryptorchidism, orchiepididymitis, atrophy of the testis, post orchidopexy state, tumors, torsion and hypogonadism. A nonselected group of 33 patients is studied. In 24 patients was coincidence in the results from gamma camera scintigraphy and echography, in 7 - lack of coincidence and in 3 - partial coincidence. It is concludied that the two methods are quick, exact and noninvasive. Gamma-camera scintigraphy is especially suitable for torsion, where the diagnosis is infallible, for cryptorchidism, varicocele and for tumors, where the necrotic zones in the testis are very precisely visualized. 3 figs., 4 refs

  8. Scintigraphic imaging of Staphylococcus aureus infection using 99mTc radiolabeled aptamers.

    Science.gov (United States)

    Santos, Sara Roberta Dos; de Sousa Lacerda, Camila Maria; Ferreira, Iêda Mendes; de Barros, André Luís Branco; Fernandes, Simone Odília; Cardoso, Valbert Nascimento; de Andrade, Antero Silva Ribeiro

    2017-10-01

    Staphylococcus aureus is a specie of great medical importance associated with many infections as bacteremia and infective endocarditis as well as osteoarticular, skin and soft tissue, pleuropulmonary, and device related infections. Early identification of infectious foci is crucial for successful treatment. Scintigraphy could contribute to this purpose since specific radiotracers were available. Aptamers due to their high specificity have great potential for radiopharmaceuticals development. In the present study scintigraphic images of S. aureus infectious foci were obtained using specific S. aureus aptamers radiolabeled with 99m Tc. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. 99m-Tc-IDA scintigraphic demonstrability of biliary elements and liver function tests in hepatobiliary diseases

    International Nuclear Information System (INIS)

    Kim, C.Y.; Bahk, Y.W.

    1982-01-01

    In the present communication, the results will be reported on a clinical study of how well scintigraphic visualization of the hepatobiliary elements and several commonly used clinical liver function tests correlate each other in various diseases of the hepatobiliary system. The demonstrability of the biliary tract, gallblader (GB) and duodenum was rather closely paralleled to serum bilirubin level and less closely to alkaline phosphatase and rather poorly to SGOT and SGPT. The biliary tree could not be visualized scintigraphically when bilirubin exceeded 10 mg/dl

  10. Scintigraphic detection of regional disruption of adrenergic neurons in the heart

    International Nuclear Information System (INIS)

    Sisson, J.C.; Lynch, J.J.; Johnson, J.; Jaques, S. Jr.; Wu, D.; Bolgos, G.; Lucchesi, B.R.; Wieland, D.M.

    1988-01-01

    Experiments were designed to detect regional disruptions of adrenergic neurons in the hearts of living dogs. The neuron disruption was achieved by the application of phenol to the epicardium of the left ventricle. Evidence for denervation was the reduction in endogenous norepinephrine (NE) concentrations in the myocardium beneath the region of phenol treatment and toward the apex. Radiolabeled meta-iodobenzylguanidine (MIBG) acts as an analog of NE and as such is concentrated in adrenergic nerve terminals. Following phenol application, MIBG labeled with 125 I was found, 20 hours after injection, to be distributed within myocardium in patterns comparable to those of NE. However, left stellectomy did not alter the distributions of NE or 125 I-MIBG in the myocardium and apparently did not disrupt adrenergic innervation. MIBG labeled with 123 I enabled scintigraphic images of heart neurons in the living dog 3 and 20 hours after injection; these images portrayed the regions of adrenergic neuron disruption caused by phenol treatment. Concentrations of thallium-201 depicted on scintigraphic image and of triphenyltetrazolium observed on in vitro staining demonstrated no myocardial injury. Thus, scintigraphy with 123 I-MIBG will display regional adrenergic denervations in the heart

  11. Scintigraphic method for evaluating reductions in local blood volumes in human extremities

    DEFF Research Database (Denmark)

    Blønd, L; Madsen, Jan Lysgård

    2000-01-01

    were carried out. No significant differences between results obtained by the use of one or two scintigraphic projections were found. The between-subject coefficient of variation was 14% in the lower limb experiment and 11% in the upper limb experiment. The within-subject coefficient of variation was 6......% in the lower limb experiment and 6% in the upper limb experiment. We found a significant relation (r = 0.42, p = 0.018) between the results obtained by the scintigraphic method and the plethysmographic method. In fractions, a mean reduction in blood volume of 0.49+0.14 (2 SD) was found after 1 min of elevation...... of the lower limb and a mean reduction of 0.45+/-0.10 (2 SD) after half a minute of elevation of the upper limb. We conclude that the method is precise and can be used in investigating physiologic and pathophysiologic mechanisms in relation to blood volumes of limbs not subject to research previously....

  12. Scintigraphic test of the vitality and functional fitness of organs conserved for transplantation

    International Nuclear Information System (INIS)

    Bozduganov, A.; Marinov, V.

    1976-01-01

    Having reviewed critically present-day methods of testing the vitality of isolated perfused organs, the authors propose their own. It is founded in the principles of colour scintigraphy after introduction of short-lived nuclides. The method was applied in testing 57 isolated preserved organs (5 kidneys, 12 livers, 5 hearts and 4 spleens from dogs; 2 kidneys and 27 livers from rabbits; 1 kidney and 1 liver from young pigs). Moreover, compararive scintigraphic and biochemical investigations were conducted on 2 dogs and 4 young pigs (A. Bozduganov, E. Simeonov, N. Bogdanova). The techniques of isolation and perfusion of the organ have been given a detailed description. Sup(113m)In was used as tracer. Areas of radioactivity deposits were visualized more or less intensely, depending on the degree of vitality and functional fitness still present actually; else, blanks were seen. Orthotransplantation and heterotransplantation with subsequent scintigraphic examination in vivo served, in scattered instances, the purpose of confirming or of rejecting ambiguous vitality findings in preserved organs. Advantages of the method are a general and specified evaluation of the organ in all of its areas; anatomical integrity of the object under test; applicability to various organs; possibility of conducting dynamic tests; accurate reproduction of vitality and functional findings, etc

  13. Gamma camera with an original system of scintigraphic image printing incorporated

    International Nuclear Information System (INIS)

    Roux, G.

    A new gamma camera has been developed, using Anger's Principle to localise the scintillations and incorporating the latest improvements which give a standard of efficiency at present competitive for this kind of apparatus. In the general design of the system special care was devoted to its ease of employment and above all to the production of high-quality scintigraphic images, the recording of images obtained from the gamma camera posing a problem to which a solution is proposed. This consists in storing all the constituent data of an image in a cell matrix of format similar to the scope of the object, the superficial information density of the image being represented by the cell contents. When the examination is finished a special printer supplies a 35x43 cm 2 document in colour on paper, or in black and white on radiological film, at 2:1 or 1:1 magnifications. The laws of contrast representation by the colours or shades of grey are chosen a posteriori according to the organ examined. Documents of the same quality as those so far supplied by a rectilinear scintigraph are then obtained with the gamma camera, which offers its own advantages in addition. The first images acquired in vivo with the whole system, gamma camera plus printer, are presented [fr

  14. 123I-BMIPP delayed scintigraphic imaging in patients with chronic heart failure

    International Nuclear Information System (INIS)

    Kida, Keisuke; Akashi, Yoshihiro J.; Yoneyama, Kihei; Shimokawa, Mitsuhiro; Musha, Haruki

    2008-01-01

    The objective of the present study was to clarify the ability of 123 I-beta-methyl-iodophenylpentadecanoic acid ( 123 I-BMIPP) to evaluate the heart-to-mediastinum (H/M) ratio and myocardial global washout rate (WR) in patients with chronic heart failure (CHF). The severity of CHF was evaluated on the basis of the New York Heart Association (NYHA) classification. Twenty patients with CHF (13 with idiopathic dilated cardiomyopathy and 7 with ischemic cardiomyopathy) and 11 age-matched controls underwent myocardial radionuclide imaging. Scintigraphic images were obtained from each participant at the early (30 min following radio-isotope injection) and late (4 h) phases using 123 I-BMIPP. The H/M ratio and WR were calculated from planar images. Concentrations of plasma brain natriuretic peptide (BNP) were measured prior to the scintigraphic study. The 123 I-BMIPP uptake of early H/M and global WR did not significantly differ among groups, but uptake of delayed H/M was significantly lower in patients with NYHA class III than in controls (control 2.47±0.39; class III 1.78±0.28 P 123 I-BMIPP uptake of delayed H/M enhances the image of CHF severity. The myocardial WR of 123 I-BMIPP also effectively depicted the severity of CHF. (author)

  15. Scintigraphic measurement of the contractile activity of the gastric antrum using factor analysis

    International Nuclear Information System (INIS)

    Bergmann, H.; Hoebart, J.; Kugi, A.; Stacher, G.; Granser, G.V.

    1990-01-01

    The motor activity of the gastric antrum is difficult to record by manometric means and scintigraphic methods have proved unsatisfactory so far as no consistent relationship between antral contractile activity and gastric emptying rate could be detected. We investigated, using data recorded in 16 healthy human subjects after the ingestion of a semisolid standard meal, whether a newly developed method employing factor analysis would yield more meaningful and reproducible results. Factor analysis was applied to sequential scintigraphic images (3-s frame time) of gastric antrum. The computed factor images and the respective factor curves are representative of distinct dynamic structures of the antrum. From the more or less sinusoidal excursions of the factor curves, which exhibited the 3 cycles per minute frequency characteristic for the stomach, amplitude, frequency and propagation velocity of antral contractions can be calculated. The amplitudes of the factor curves were used to calculate a contraction index. This contraction index was found to be correlated significantly negatively with the gastric half-emptying time of the ingested meal. The employed factor analytical approach thus seems a promising tool to further investigate the role of antral contractility in the process of gastric emptying. (Authors)

  16. A simple method for determining split renal function from dynamic {sup 99m}Tc-MAG3 scintigraphic data

    Energy Technology Data Exchange (ETDEWEB)

    Wesolowski, Michal J.; Watson, Gage; Wanasundara, Surajith N.; Babyn, Paul [University of Saskatchewan, Department of Medical Imaging, Saskatoon, SK (Canada); Conrad, Gary R. [University of Kentucky College of Medicine, Department of Radiology, Lexington, KY (United States); Samal, Martin [Charles University Prague and the General University Hospital in Prague, Department of Nuclear Medicine, First Faculty of Medicine, Praha 2 (Czech Republic); Wesolowski, Carl A. [University of Saskatchewan, Department of Medical Imaging, Saskatoon, SK (Canada); Memorial University of Newfoundland, Department of Radiology, St. John' s, NL (Canada)

    2016-03-15

    Commonly used methods for determining split renal function (SRF) from dynamic scintigraphic data require extrarenal background subtraction and additional correction for intrarenal vascular activity. The use of these additional regions of interest (ROIs) can produce inaccurate results and be challenging, e.g. if the heart is out of the camera field of view. The purpose of this study was to evaluate a new method for determining SRF called the blood pool compensation (BPC) technique, which is simple to implement, does not require extrarenal background correction and intrinsically corrects for intrarenal vascular activity. In the BPC method SRF is derived from a parametric plot of the curves generated by one blood-pool and two renal ROIs. Data from 107 patients who underwent {sup 99m}Tc-MAG3 scintigraphy were used to determine SRF values. Values calculated using the BPC method were compared to those obtained with the integral (IN) and Patlak-Rutland (PR) techniques using Bland-Altman plotting and Passing-Bablok regression. The interobserver variability of the BPC technique was also assessed for two observers. The SRF values obtained with the BPC method did not differ significantly from those obtained with the PR method and showed no consistent bias, while SRF values obtained with the IN method showed significant differences with some bias in comparison to those obtained with either the PR or BPC method. No significant interobserver variability was found between two observers calculating SRF using the BPC method. The BPC method requires only three ROIs to produce reliable estimates of SRF, was simple to implement, and in this study yielded statistically equivalent results to the PR method with appreciable interobserver agreement. As such, it adds a new reliable method for quality control of monitoring relative kidney function. (orig.)

  17. Scintigraphic evaluation of primary congenital hypothyroidism: results of the Greek screening program

    Energy Technology Data Exchange (ETDEWEB)

    Panoutsopoulos, G.; Ilias, I.; Batsakis, C.; Christakopoulou, I. [Dept. of Nuclear Medicine, ' ' Sotiria' ' Hospital, Athens (Greece); Mengreli, C. [Inst. of Child Health, Athens (Greece)

    2001-04-01

    The Greek screening program for primary congenital hypothyroidism was initiated in 1979. By early 2000, thyrotropin measurements had been performed in 1,976,719 newborns, using dried blood spots obtained by heel prick. Among these children, 584 were diagnosed with congenital hypothyroidism (incidence: 1/3,384 births) and were given L-thyroxine (L-T{sub 4}) replacement therapy. In order to further evaluate and classify the children as having either an aplastic (AT) or an ectopic thyroid gland (ET) or as showing thyroidal dyshormonogenesis (DN, with a nomotopic gland), scintigraphic studies were performed at the age of 2-3 years. In 413 children of this age group (including 24 subsequently diagnosed as having had transient hypothyroidism, in whom L-T{sub 4} therapy was not resumed), thyroid hormones were measured and scintigraphic studies were done after withdrawal of L-T{sub 4} replacement treatment for 3 weeks. Given the long duration of the study, we used various scintigraphic modalities. In 96 children (group A), scintigraphy was performed using technetium-99m pertechnetate ({sup 99m}TcO{sub 4}{sup -}; 18.5 MBq given i.v.) and a rectilinear scanner. Seventy-three children (group B) were studied with {sup 99m}TcO{sub 4}{sup -} (18.5 MBq given i.v.) and a gamma camera equipped with a pinhole collimator. In these groups, atropine was administered 30 min prior to the study (0.02 mg/kg i.v. or i.m.) in order to reduce the secretion of saliva from the salivary glands. Finally, in the remaining 220 children (group C) iodine-123 sodium iodide ({sup 123}I-Na) (0.74-1.85 MBq i.v.) and the same gamma camera were used. Between-group comparisons of scintigraphic findings were done with the chi square test. In 191 children from group C, thyroglobulin (Tg) was measured and in 49 children ultrasound (US) was performed (categorising the gland as AT or ET/DN). Comparison of these modalities was done with the kappa statistic. In group A, 61.5% of children had AT, 26.0% had ET and

  18. Probabilistic flood extent estimates from social media flood observations

    NARCIS (Netherlands)

    Brouwer, Tom; Eilander, Dirk; Van Loenen, Arnejan; Booij, Martijn J.; Wijnberg, Kathelijne M.; Verkade, Jan S.; Wagemaker, Jurjen

    2017-01-01

    The increasing number and severity of floods, driven by phenomena such as urbanization, deforestation, subsidence and climate change, create a growing need for accurate and timely flood maps. In this paper we present and evaluate a method to create deterministic and probabilistic flood maps from

  19. Probabilistic flood extent estimates from social media flood observations

    NARCIS (Netherlands)

    Brouwer, Tom; Eilander, Dirk; Van Loenen, Arnejan; Booij, Martijn J.; Wijnberg, Kathelijne M.; Verkade, Jan S.; Wagemaker, Jurjen

    2017-01-01

    The increasing number and severity of floods, driven by phenomena such as urbanization, deforestation, subsidence and climate change, creates a growing need for accurate and timely flood maps. This research focussed on creating flood maps using user generated content from Twitter. Twitter data has

  20. Forest extent and deforestation in tropical Africa since 1900.

    Science.gov (United States)

    Aleman, Julie C; Jarzyna, Marta A; Staver, A Carla

    2018-01-01

    Accurate estimates of historical forest extent and associated deforestation rates are crucial for quantifying tropical carbon cycles and formulating conservation policy. In Africa, data-driven estimates of historical closed-canopy forest extent and deforestation at the continental scale are lacking, and existing modelled estimates diverge substantially. Here, we synthesize available palaeo-proxies and historical maps to reconstruct forest extent in tropical Africa around 1900, when European colonization accelerated markedly, and compare these historical estimates with modern forest extent to estimate deforestation. We find that forests were less extensive in 1900 than bioclimatic models predict. Resultantly, across tropical Africa, ~ 21.7% of forests have been deforested, yielding substantially slower deforestation than previous estimates (35-55%). However, deforestation was heterogeneous: West and East African forests have undergone almost complete decline (~ 83.3 and 93.0%, respectively), while Central African forests have expanded at the expense of savannahs (~ 1.4% net forest expansion, with ~ 135,270 km 2 of savannahs encroached). These results suggest that climate alone does not determine savannah and forest distributions and that many savannahs hitherto considered to be degraded forests are instead relatively old. These data-driven reconstructions of historical biome distributions will inform tropical carbon cycle estimates, carbon mitigation initiatives and conservation planning in both forest and savannah systems.

  1. The use of 111In-labelled platelets for scintigraphic localization of gastrointestinal bleeding with special reference to occult bleeding

    International Nuclear Information System (INIS)

    Gjerloeff Schmidt, K.; Waever Rasmussen, J.; Grove, O.; Andersen, D.

    1986-01-01

    Gamma-camera imaging of the abdomen after injection of autologous 111 In-labelled platelets was applied for localization of gastrointestinal bleeding in a study of 22 patients. In 15 studies showing scintigraphic signs of bleeding, the clinical presentation included occult bleeding in 6, melaena in 4, and bloody stools in 5 patients. Scintigraphy could be done repeatedly for up to 1 week after a single tracer injection. The time interval between the injection and scintigraphic visualization of bleeding ranged from 10 min to 68 h, being longest in cases of occult bleeding. In most cases the scintigraphic findings were supported by other diagnostic modalities, including surgical removal of presumed sources of bleeding. In seven studies without scintigraphic signs of bleeding, a probable source of bleeding was identified by other means in one patient. The 111 In-platelet method seems to be a promising method for localization of gastrointestinal bleeding which may prove particularly useful in cases of occult or recurrent bleeding

  2. The value of scintigraphic examinations in the diagnosis of pathologic processes in the posterior scala in childhood and youth

    International Nuclear Information System (INIS)

    Piepgras, U.; Huber, G.; Emde, H.

    1980-01-01

    The diagnostical possibilities of computerized tomography (CT) and brain scintigraphy are compared. Serial scintigraphy by gamma cameras, scintigraphic examinations of the liquor space and the ventricles are discussed, too. In addition to CT, scintigraphy is also recommended in the following cases: hydrocephalus of unknown origin, dilatation of the IVth ventricle, diagnosis of recidive tumours, and unclear density differences. (L.E.)

  3. Epiphyseal involvement in Erdheim-Chester disease: radiographic and scintigraphic findings in a case with lytic lesions

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz-Hernandez, G.; Tajahuerce-Romera, G.M.; Latorre-Ibanez, M.D.; Lara-Pomares, A. [Servicio de Medicina Nuclear, Hospital Provincial de Castellon (Spain); Vila-Fayos, V. [Servicio de Reumatologia, Hospital Comarcal de Vinaroz (Spain)

    2000-08-01

    We reported a symmetric increase of activity in lower links secondary to Erdheim-Chester disease and demonstrated by bone scans and radiographs. An inusual scintigraphic and radiographic appearance with epiphyseal involvement and lytic lesions is described. Differential diagnosis of bone scan and radiographic findings is discussed. (orig.)

  4. Targeting of macrophages for the scintigraphic evaluation of inflammatory lesions in a model of radio-induced inflammation in pigs

    International Nuclear Information System (INIS)

    Hoffschir, D.; Daburon, F.; Normier, G.; Binz, H.; Le Pape, A.

    1991-01-01

    For a new scintigraphic strategy based on the targeting of macrophages recruited by inflammatory lesions, a specific ligand able to interact with these cells both in vitro and in vivo has been developed. J001 is a 34 KDa acylated peptidopoly 1-3 galactoside isolated from proteoglycans of a non pathogenic strain of klebsiella. When labelled with 99mTc then administrated by aerosol, this agent has been demonstrated to be a potent tool for the scintigraphic imaging of inflammatory lymph nodes in experimental berylliosis and in patients with sarcoidosis, lung tumors and ganglionic metastases. An experimental model was developed in pigs using an acute and localized muscular γ irradiation in the limb and skin resection to prevent ulceration. Dynamic imaging was performed during two hours after intravenous injection of 1 mg J001 labelled with 370 MBq 99mTc in the presence of 0.125 mg stannous fluoride. The perfusion of the lesions was evaluated from scintigraphic data obtained both 15 min after IV injection of J001 or 99mTc 04-. The intensity of the fixation of J001 was quantified 2 hours after injection and expressed as a scintigraphic ratio: R2h = cpm in lesion / cpm in a defined healthy area in the same limb. After induction of irradiation, scintigraphic ratios exhibited a progressive increase to reach a maximum (R2h = 3.6) after 3 months. Then, they decreased to recover a normal value about 6 months after irradiation. At that time, histological controls and clinical observations exhibited a significant decrease in inflammatory reaction, macrophages recruitment and apparition of fibrosis. J001 fixation was very sensitive to corticosteroids that resulted in a complete clearing of the scintigraphic images 12 to 24 hours after treatment. Two weeks were then required for a complete recovery of the inflammatory reaction and J001 fixation. So, targeting of macrophages with J001 should offer a sensitive and specific tool for the scintigraphic assessment of inflammation and

  5. Analysis of stress fractures associated with lameness in Thoroughbred flat racehorses training on different track surfaces undergoing nuclear scintigraphic examination.

    Science.gov (United States)

    MacKinnon, M C; Bonder, D; Boston, R C; Ross, M W

    2015-05-01

    There is limited information regarding the impact of training track surface on the occurrence of stress fractures. To evaluate the impact of training track surface on the proportion of long bone and pelvic stress fractures associated with lameness in Thoroughbred horses in flat race training undergoing nuclear scintigraphic examination. Retrospective study. Scintigraphic examinations of Thoroughbred flat racehorses were evaluated from 2 hospitals (hospital A [Toronto Equine Hospital], 2003-2009, and hospital B [George D. Widener Hospital for Large Animals, School of Veterinary Medicine, University of Pennsylvania], 1994-2006). Horses admitted to hospital A trained at a single track, at which the main training surface changed from dirt to synthetic on 27 August 2006. Two distinct populations existed at hospital B: horses that trained on dirt (numerous trainers) and those that trained on turf (single trainer). All scintigraphic images were evaluated by a blinded reviewer. Fisher's exact test and logistic regression were used when appropriate, and significance was set at Pfractures detected in scintigraphic examinations from horses training on a synthetic surface (31.7%) in comparison to scintigraphic examinations from horses training on a dirt surface (23.0%) at an earlier point in time (P = 0.03). There was a greater proportion of hindlimb/pelvic and tibial stress fractures diagnosed in horses from the synthetic surface-trained group than from the dirt-trained group at hospital A (Pfractures diagnosed, but other factors, such as training philosophy, appear to be important. Future prospective investigations to fully elucidate the relationship between training track surface and the proportion of stress fractures and other nonfatal musculoskeletal injuries are warranted. © 2014 EVJ Ltd.

  6. Scintigraphic evaluation of the osteoblastic activity of rabbit tibial defects after HYAFF11 membrane application.

    Science.gov (United States)

    Mermerkaya, Musa Uğur; Doral, Mahmut Nedim; Karaaslan, Fatih; Huri, Gazi; Karacavuş, Seyhan; Kaymaz, Burak; Alkan, Erkan

    2016-05-03

    An unfavorable condition for bone healing is the presence of bone defects. Under such conditions, a material can play a role to cover fractured or defective bone. Technological advances now allow for the use of such material. Hyalonect(®) (Fidia Advanced Biopolymers SLR, Italy), a novel membrane comprising knitted fibers of esterified hyaluronan (HYAFF11) can be used to cover fractured or grafted bone and can also serve as a scaffold to keep osteoprogenitor cells in place. The aim of this study was to compare osteoblastic activity by the use of scintigraphic methods in defective rabbit tibias during early-phase bone healing with or without a hyaluronan-based mesh. Two groups (A and B) of New Zealand albino rabbits were used; each group included 10 animals. Operations on all rabbits were performed under general anesthesia. We also resected 10-mm bone segments from each animal's tibial diaphysis. After resection, tibias with defects were fixed using Kirschner wires. In group A, no hyaluronan-based mesh was used. In group B, tibial segmental defects were enclosed with a hyaluronan-based mesh. The rabbits were followed up for 4 weeks postoperatively, after which bone scintigraphic studies were performed on each animal to detect and compare osteoblastic activity. The mean count in the fracture side of the hyaluronan-based mesh group was significantly higher compared to that of the group A (p = 0.019). However, there was no significant difference between group B and control rabbits with respect to the mean count on the intact bone side (p = 0.437). The bone defect (fracture)/intact bone mean count ratio was significantly higher in group B compared to group A (p = 0.008). A hyaluronan-based mesh plays a role in promoting osteoblastic activity. Hyalonect(®) is suitable for restoring tissue continuity whenever the periosteal membrane is structurally impaired or inadequate. Our results demonstrated that, during early-phase bone healing, osteoblastic activity

  7. Diagnostic accuracy of scintigraphic methods in the differential diagnosis of focal liver lesions

    International Nuclear Information System (INIS)

    Czermak, H.; Gomez, I.; Gallowitsch, H.J.; Lind, P.

    1993-01-01

    In a retrospective study of 160 patients who were examined within 12 months, we analysed the diagnosic value of scintigraphic techniques in the differential diagnosis of solid focal liver lesions. Haemangiomas were found in 77 patients. Bloodpool scintigraphy was true-positive in 66 (sensivitity 85%); for lesions greater than 2 cm in diameter, sensitivity increased to 94%. Metastases of CEA-expressing tumors were found in 42 patients, anti-CEA-immunoscintigraphy was true-positive in 33 patients (sensitivity 78.5%). Focal nodulary hyperplasia was found in 3 patients, adenomas in 6 patients. In the remaining 32 patiens we saw 4 hepatocellular carcinomas, 28 metastases from lung and breast cancer, 2 echinococcus cysts and 1 choledochus cyst. (orig.) [de

  8. Scintigraphic localization of pheochromocytomas using 131 I-meta-iodobenzylguanidine. Comparison with computerized tomography

    International Nuclear Information System (INIS)

    Charbonnel, B.; Coornaert, S.; Tellier, J.L.; Peltier, P.; Chatal, J.F.

    1984-01-01

    Meta-iodobenzylguanidine was synthesized, radiolabelled with I 131 or I 123 and injected to 28 controls and 7 patients totalizing 13 foci of pheochromocytoma. The tumour was located in one adrenal gland in 3 cases, in both adrenal glands in 1 case, and between the aorta and the vena cava in 1 case; 2 were malignant with metastases. Scintigraphy was negative in all controls, whereas all pheochromocytomas were clearly demonstrated 24 h after injection, except one regarded as non functional due to necrosis. By comparison, CT readily showed the tumour in 7 cases, showed it only thanks to scintigraphic guidance in 4 cases and failed in 2 cases. It is concluded that scintigraphy with meta-iodo-benzylguanidine provides a safe and reliable means of locating a wide range of pheochromocytomas [fr

  9. Scintigraphic disagreement in the study of thyroid nodules using technetium 99m and iodine 131

    International Nuclear Information System (INIS)

    Planchon, C.A.

    1977-01-01

    116 patients with thyroid nodules, iso or hyperfixing, heterogeneous or scintigraphically indistinct after administration of pertechnetate 99mTc, were systematically re-examined with iodine 131. The results of this study are as follows: 1) 99mTc, while its advantages justify its extensive application, is an imperfect tracer and cannot replace iodine 131 altogether. In fact in 12% of the cases the results were conflicting. 2) The technological conditions may sometimes be to blame but the hypothesis of a special metabolic behavior of the nodule examined seems plausible in certain cases of disagreement (blocking of hormone synthesis and escape of non-hormonal iodine). 3) These observations correspond to no particular anatomo-clinical factors. The legitimate conclusion therefore is that the exclusive use of 99mTc could result in failure to recognise a non-functional nodule (1 case in about 10), a possibility not to be neglected because of the risk of cancer [fr

  10. Right ventricular function: methodologic and clinical considerations in noninvasive scintigraphic assessment

    International Nuclear Information System (INIS)

    Manno, B.V.; Iskandrian, A.S.; Hakki, A.H.

    1984-01-01

    Right ventricular function plays an important role in many cardiac disorders. Changes in left ventricular function, right ventricular afterload and preload, cardiac medications and ischemia may affect right ventricular function. Radionuclide ventriculography permits quantitative assessment of regional and global function of the right ventricle. This assessment can be made at rest, during exercise or after pharmacologic interventions. The overlap between right ventricle and right atrium is a major limitation for gated scintigraphic techniques. The use of imaging with newer short-lived radionuclides may permit more accurate and reproducible assessment of right ventricular function by means of the first pass method. Further work in areas related to improvement of techniques and the impact of right ventricular function on prognosis is needed

  11. Scintigraphic and Endoscopic Evaluation of Radiation-induced Acute Gastrointestinal Syndrome in Micro-pig Model

    International Nuclear Information System (INIS)

    Lee, Seung-Sook; Kim, Kyung-Min; Kim, Jin; Jang, Won-Suk; Lee, Jung-Eun; Kim, Noo-Ri; Lee, Sun-Joo; Kim, Mi-Sook; Ji, Young-Hoon; Cheon, Gi-Jeong; Lim, Sang-Moo

    2007-01-01

    Micro-pig model can be served as a proper substitute for humans in studying acute radiation syndrome following radiation-exposure accidents, especially showing similar clinico-pathologic response of hematopoietic and gastrointestinal (GI) syndrome to human. Among acute GI syndrome induced by radiation, GI motility disturbance has not been studied, however, it would be important in a viewpoint of affecting infectious progression from GI tract. Here, we employed scintigraphy of GI transit time and sequential endoscopic examination and tissue sampling in micropigs followed by abdominal radiation exposure. The specific aims of this study are to evaluate objective evidence of GI motility disturbance by scintigraphic evaluation and to find corresponding clinicoapthologic changes in radiation-induced acute GI syndrome

  12. Scintigraphic control of bone-fracture healing under ultrasonic stimulation: An animal experimental study

    International Nuclear Information System (INIS)

    Klug, W.; Franke, W.G.; Knoch, H.G.

    1986-01-01

    In a model of closed lower-leg fracture in rabbits and of secondary bone-fracture healing, scintigraphic control until biological healing was performed. Biological fracture healing was assumed for a region of interest (ROI)-activity ratio close to 1.0. After application of sup(99m)Tc-HEDP, 151 examinations were performed. ROI activity increased significantly until day 14 p.i. and reached the maximum value (Q=6.44) on day 14 postfracture. Sixty-one lower leg fractures were treated by ultrasound from days 14-28 postfractures. These stimulated fractures were biologically healed on day 168 postfracture. The fractures that were not treated by ultrasound could not be detected by scanning after day 203 postfracture. (orig.)

  13. A paper sheet phantom for scintigraphic planar imaging. Usefulness of pouch-laminated paper source

    International Nuclear Information System (INIS)

    Takaki, Akihiro; Soma, Tsutomu; Murase, Kenya; Teraoka, Satomi; Murakami, Tomonori; Kojima, Akihiro; Matsumoto, Masanori

    2007-01-01

    In order to perform experimental measurements for evaluation of imaging device's performance, data acquisition technique, and clinical images on scintigraphic imaging, many kinds of phantoms are employed. However, since these materials are acrylic and plastic, the thickness and quality of those materials cause attenuation and scatter in itself. We developed a paper sheet phantom sealed with a pouch laminator, which can be a true radioactive source in air. In this study, the paper sheet phantom was compared to the acrylic liver phantom, with the thickness of 2 cm, which is commercially available. The results showed that although some scatter counts were contained within the image of the acrylic liver phantom, there were few scattered photons in the paper sheet phantom image. Furthermore, this laminated paper sheet phantom made handling of the source and its waste easier. If the paper sheet phantom will be designed more sophisticatedly, it becomes a useful tool for planar imaging experiments. (author)

  14. Scintigraphic demonstration of single- or two-phase gastric emptying in diabetics

    International Nuclear Information System (INIS)

    Eikman, E.A.; Leichter, S.; Waldholtz, B.; Tenorio, L.; Brady, P.

    1989-01-01

    This paper discusses how a modified scintigraphic test of gastric emptying revealed two types of abnormal gastric emptying in diabetic patients. After ingestion of 100 mL of cooked egg whites labeled with 0.5 mCi of Tc-99m sulfur colloid, the geometric mean stomach radioactivity was recorded serially for 90 minutes. Linear regression computed for the log of radioactivity versus time facilitated recognition of changes in gastric emptying. In 16 of 25 consecutive diabetic patients with postprandial symptoms, initial slow emptying (half-life,>100 minutes) was observed. Single-phase emptying was shown in seven of these patients. In nine patients, the slow-emptying phase lasted up to 50 minutes, followed by a distinct second phase of normal or rapid emptying (half-life, <40 minutes). The existence of different gastric emptying implies differing mechanisms of delay and may be important in treatment

  15. Novel CT and scintigraphic findings of bone metastasis from invasive lobular breast cancer.

    Science.gov (United States)

    Al-Ogaili, Zeyad; Troedson, Russell

    2016-02-01

    The aim of this study is to identify and describe the computed tomography and scintigraphic imaging patterns of osseous metastasis from invasive lobular breast cancer (ILC). CT and skeletal scintigraphy (SS) studies of 23 patients with diagnosis of ILC and osseous metastasis on their initial presentation were reviewed. Osseous metastases in 14 patients (60.8%) appear as uniform small sclerotic lesions (USSL) on CT scan. The SS in these patients were interpreted as negative for metastasis (either normal or with some equivocal findings not typical for metastasis). Osseous metastasis from ILC can have a characteristic imaging pattern on CT and SS. The pattern of USSL on CT scan with negative SS is highly suggestive of osseous metastasis from ILC. © 2015 The Royal Australian and New Zealand College of Radiologists.

  16. Novel CT and scintigraphic findings of bone metastasis from invasive lobular breast cancer

    International Nuclear Information System (INIS)

    Al-Ogaili, Zeyad; Troedson, Russell

    2016-01-01

    The aim of this study is to identify and describe the computed tomography and scintigraphic imaging patterns of osseous metastasis from invasive lobular breast cancer (ILC). CT and skeletal scintigraphy (SS) studies of 23 patients with diagnosis of ILC and osseous metastasis on their initial presentation were reviewed.Osseous metastases in 14 patients (60.8%) appear as uniform small sclerotic lesions (USSL) on CT scan. The SS in these patients were interpreted as negative for metastasis (either normal or with some equivocal findings not typical for metastasis). Osseous metastasis from ILC can have a characteristic imaging pattern on CT and SS. The pattern of USSL on CT scan with negative SS is highly suggestive of osseous metastasis from ILC.

  17. Coincidence of scintigraphic false positive and false negative findings in parathyroid and thyroid adenomas (case report)

    Energy Technology Data Exchange (ETDEWEB)

    Mana, O.; Zatta, G.; Boccolari, S.; Barbesti, S.; Tarolo, G.L.

    1987-04-01

    The subtractive double tracer scintigraphy with /sup 201/Tl and /sup 99m/Tc is a useful technique in studying parathyroid nodules; nevertheless, this method can give misleading informations especially in presence of thyroid nodules with false positive and false negative findings. In this case report the technique was applied in studying a patient with three nodules (two thyroid adenomas and one parathyroid adenoma), where both scintigraphic and echographic methods provided misleading informations. The selective uptake of /sup 201/Tl in the upper region of the right thyroid lobe gave a false positive finding, while the increased uptake of /sup 99m/Tc in a hyperfunctioning thyroid adenoma of left lobe masked the parathyroid adenoma laying below, giving a false negative finding.

  18. Scintigraphic evaluation of floating, gastroretentive formulation of clarithramycin in healthy human volunteers

    International Nuclear Information System (INIS)

    Ali, Raisuddin; Aji Alex, M.R.; Dutta, M.; Singh, Thakuri; Bhatnagar, A.; Bajaj, M.; Singla, Y.P.; Ahmad, F.J.; Khar, R.K.

    2010-01-01

    Full text: Objective of the present study concerns formulation and evaluation of oral buoyant effervescent tablets of clarithromycin for prolongation of gastric residence time (GRT) and to enhance eradication of Helicobacter pylori (H. pylori) for longer period of time. Materials and Methods: Clarithromycin (CLA) a macrolide antibiotic was chosen as the candidate drug for its immense potential as an Anti H. pylori agent. HPMC and/or xanthan gum were used as release-retarding polymer(s) whereas sodium bicarbonate (NaHCO 3 ) was utilized as a gas former. The tablets were prepared by wet granulation method. Formulations were evaluated for physicochemical properties, in vitro drug release as well as drug release kinetics and stability studies. In vivo gamma scintigraphic studies were assessed for the optimized buoyant gastroretentive tablets in six healthy human volunteers to study influence of nature of the dosage form i.e. conventional or sustained release gastroretentive tablets and the presence of food in the stomach on intragastric performance of gastroretentive tablets. Result: The fabricated tablets showed acceptable physiochemical properties. Non-fickian release transport was confirmed as the drug release mechanism from the prepared tablets. Optimized tablets composed of HPMC K15M, xanthan gum, and NaHCO 3 were promising systems exhibiting excellent floating properties. The overall performance was found to be highly sustained. Scintigraphic imaging revealed GRT of 320 min or more in fed state on the other hand GRT of 180 min or less in case of unfed state. Conclusion: The developed gastroretentive system has potential to increase efficacy of the therapy and improve patient

  19. 123I-BMIPP delayed scintigraphic imaging in patients with chronic heart failure.

    Science.gov (United States)

    Kida, Keisuke; Akashi, Yoshihiro J; Yoneyama, Kihei; Shimokawa, Mitsuhiro; Musha, Haruki

    2008-11-01

    The objective of the present study was to clarify the ability of 123I-beta-methyl-iodophenylpentadecanoic acid (123I-BMIPP) to evaluate the heart-to-mediastinum (H/M) ratio and myocardial global washout rate (WR) in patients with chronic heart failure (CHF). The severity of CHF was evaluated on the basis of the New York Heart Association (NYHA) classification. Twenty patients with CHF (13 with idiopathic dilated cardiomyopathy and 7 with ischemic cardiomyopathy) and 11 age-matched controls underwent myocardial radionuclide imaging. Scintigraphic images were obtained from each participant at the early (30 min following radio-isotope injection) and late (4 h) phases using 123I-BMIPP. The H/M ratio and WR were calculated from planar images. Concentrations of plasma brain natriuretic peptide (BNP) were measured prior to the scintigraphic study. The 123I-BMIPP uptake of early H/M and global WR did not significantly differ among groups, but uptake of delayed H/M was significantly lower in patients with NYHA class III than in controls (control 2.47 +/- 0.39; class III 1.78 +/- 0.28, P < 0.05). The uptake of delayed H/M and global WR correlated with plasma log BNP in all participants (r = -0.38, P < 0.05; 0.43, P < 0.05, respectively). These data suggest that 123I-BMIPP uptake of delayed H/M enhances the image of CHF severity. The myocardial WR of 123I-BMIPP also effectively depicted the severity of CHF.

  20. 201Tl scintigraphic evaluation of tumor mass and viability of bone and soft-tissue tumors

    International Nuclear Information System (INIS)

    Tsuda, Takatoshi; Kubota, Masahiro; Yoshida, Satoru; Shibata, Masahito; Wakabayashi, Jun-ichi; Obata, Hiroyuki; Matsuyama, Toshikatsu; Usui, Masamichi; Ishii, Sei-ichi.

    1994-01-01

    To characterize 201 Tl uptake in patients with bone and soft-tissue tumor, we studied 49 patients with surgically proven tumors and one patient with a tumor diagnosed arteriographically. In 37 of our 50 patients, the tumor was evaluated with 201 Tl and arteriography. Moreover, in 14 of patients with pre-operative chemotherapy, pathologic changes were graded on the basis of percent tumor necrosis as defined histologically. The percent tumor necrosis histologically was compared with changes in the scintigraphic and conventional angiographic studies. Radiologic comparisons demonstrated a high degree of correlation with images of 201 Tl and both arterial and blood pool phase of 99m Tc-HMDP. Ninety-six percent of 28 malignant tumors had positive 201 Tl uptake. None of the patients showed any thallium accumulation in the soft tissues or skeleton adjacent to the lesion. Activity of 201 Tl was mainly dependent upon a tumor blood flow and a vascular density. In of 14 cases with the preoperative chemotherapeutic treatment, 201 Tl scintigraphic changes showed concordance with % tumor necrosis. Thallium-201 was superior to 99m Tc-HMDP in predicting tumor response to chemotherapy. Interestingly, delayed images of 99m Tc-HMDP of 5 responders with >90% tumor necrosis showed decreased uptake in the adjacent bone to the tumor mass lesions. It seems to be quite all right to consider that a major determinant of 201 Tl uptake is intratumoral angiogenecity, which is closely connected with tumor viability. Therefore, 201 Tl is a sensitive radiopharmaceutical for detection of vascular rich bone and soft-tissue tumors, and appears to be a simple and an accurate test for evaluating the response to specific therapeutic regimens of malignant bone and soft-tissue tumors. (author)

  1. Acetabular stress fractures in military endurance athletes and recruits: incidence and MRI and scintigraphic findings

    International Nuclear Information System (INIS)

    Williams, T.R.; Puckett, M.L.; Shin, A.Y.; Gorman, J.D.; Denison, G.

    2002-01-01

    Objective: To evaluate the incidence and the MRI and scintigraphic appearance of acetabular stress (fatigue) fractures in military endurance athletes and recruits. Design and patients: One hundred and seventy-eight active duty military endurance trainees with a history of activity-related hip pain were evaluated by both MRI and bone scan over a 2-year period. Patients in the study ranged in age from 17 to 45 years. They had hip pain related to activity and had plain radiographs of the hip and pelvis that were interpreted as normal or equivocal. The study was originally designed to evaluate the MRI and scintigraphic appearance of femoral neck stress fractures. Patients had scintigraphy and a limited MRI examination (coronal imaging only) within 48 h of the bone scan. Twelve patients demonstrated imaging findings compatible with acetabular stress fractures. Results: Stress fractures are common in endurance athletes and in military populations; however, stress fracture of the acetabulum is uncommon. Twelve of 178 patients (6.7%) in our study had imaging findings consistent with acetabular stress fractures. Two patterns were identified. Seven of the 12 (58%) patients had acetabular roof stress fractures. In this group, two cases of bilateral acetabular roof stress fractures were identified, one with a synchronous tensile sided femoral neck stress fracture. The remaining five of 12 (42%) patients had anterior column stress fractures, rarely occurring in isolation, and almost always occurring with inferior pubic ramus stress fracture (4 of 5, or 80%). One case of bilateral anterior column stress fractures was identified without additional sites of injury. Conclusions: Stress fractures are commonplace in military populations, especially endurance trainees. Acetabular stress fractures are rare and therefore unrecognized, but do occur and may be a cause for activity-related hip pain in a small percentage of military endurance athletes and recruits. (orig.)

  2. The Extent of Immature Fish Harvesting by the Commercial Fishery ...

    African Journals Online (AJOL)

    The sustainability of a given fishery is a function of the number of sexually matured fish present in water. If there is intensive immature fishing, the population of fish reaching the stage of recruitment will decrease, which in turn results in lower yield and biomass. The present study was conducted to estimate the extent of ...

  3. Scintigraphic assessment of cerebral blood flow changes in chrongic tobacco users using Tc-99m HMPAO brain SPECT

    International Nuclear Information System (INIS)

    Saeed, S.; Raza, M.; Sohaib, M.

    2004-01-01

    HMPAO SPECT is a useful and readily available method for estimation of rCBE This study aimed at defining a correlation between chronic tobacco use and changes in cerebral blood flow, through visual and semi-quantitative scintigraphic assessment, rCBF in 48 chronic tobacco users and 11 quitters was evaluated, utilising a normal database created by HMPAO brain scans of 20 non-smokers. Subjects were classified into chronic tobacco users and non-tobacco users through the smoking index (SI). SI value of 100 was taken as the cut-off value. Tobacco users who had discontinued tobacco use for three months or more were classified as 'Quitters'. ROIs were declared hypo- or hyper-perfused if their percentage perfusion values relative to the average perfusion per pixel of the whole slice did not fall within + 2 SD of the mean regional perfusion in the corresponding ROI, in the normal control group.rCBF in chronic tobacco users was found to be far less than the non-tobacco users (P < 0.001). The quitters showed significantly better cerebral perfusion compared to the chronic tobacco users (P < 0.025) but their rCBF was still significantly decreased relative to the non-tobacco users (P < 0.005). In chronic tobacco users, the rCBF was decreased in parietal (P < 0.05) and occipital (P < 0.005) regions of the cortex, and increased in the temporal cortex (P < 0.001). The frontal cortex showed both hyperperfusion (P < 0.001) and hypoperfusion (P < 0.025), perhaps due to varying perfusion patterns in different areas / sub-regions of the frontal cortex. The cerebellar blood flow in chronic tobacco users was much decreased compared to the normal controls (P < 0.001).Generally, a satisfactory correlation between the results obtained visually and semi-quantitatively was found. Semi-quantitative approach, however, appeared better specially when regional radiotracer uptake (actual acquired average regional counts) were used as an adjunct to support the findings. (authors)

  4. Nontraumatic femoral head necrosis. Classification of bone scintigraphic findings and diagnostic value of SPECT following planar imaging

    Energy Technology Data Exchange (ETDEWEB)

    Minoshima, Satoshi; Uchida, Yoshitaka; Anzai, Yoshimi; Uno, Kimiichi; Arimizu, Noboru [Chiba Univ. (Japan). School of Medicine

    1994-09-01

    This study was conducted to determine bone scintigraphic findings in nontraumatic femoral head avascular necrosis and diagnostic value of SPECT imaging following a conventional planar imaging. Forty-three femoral heads in twenty-six cases with idiopathic femoral head necrosis (n=2), systemic lupus erythematosus (n=22), aplastic anemia (n=1), and renal transplantation (n=1) were studied. The diagnosis for femoral head necrosis was based on magnetic resonance imaging as well as other diagnostic studies in all cases. Scintigraphic findings of planar and SPECT images were classified into six categories: normal (N); cold or decrease (C); partial increase with cold or decrease (PH+C); ring-like increase with a cold center (RH+C); partial increase (PH); diffuse and/or irregular increase (DH). Avascular necrosis was confirmed in twenty-four femoral heads, in which planar and SPECT images showed scintigraphic findings of N (n=3, 2), C (n=1, 3), PH+C (n=2, 8), RH+C (n=2, 3), PH (n=9, 2), and DH (n=7, 6), respectively. Femoral heads without avascular necrosis demonstrated planar and SPECT findings of N (n=16, 12), C (n=0, 6), and DH (n=3, 1), respectively. When considering C, PH+C, and RH+C as diagnostic findings for avascular necrosis, sensitivities of planar and SPECT images were 21% and 58%, and specificities were 100% and 68%, respectively. In nineteen femoral heads with normal planar findings (N), SPECT correctly identified avascular necrosis in two femoral heads and misidentified six normal femoral heads as avascular necrosis. In nineteen femoral heads with nondiagnostic abnormalities (PH, DH), SPECT correctly identified avascular necrosis in seven femoral heads and showed no false positive. Diagnostic planar findings in five femoral heads were concordant with SPECT diagnosis. These results indicate that SPECT imaging is most valuable when planar images show nondiagnostic abnormalities based on the proposed classification of scintigraphic findings. (author).

  5. Nontraumatic femoral head necrosis. Classification of bone scintigraphic findings and diagnostic value of SPECT following planar imaging

    International Nuclear Information System (INIS)

    Minoshima, Satoshi; Uchida, Yoshitaka; Anzai, Yoshimi; Uno, Kimiichi; Arimizu, Noboru

    1994-01-01

    This study was conducted to determine bone scintigraphic findings in nontraumatic femoral head avascular necrosis and diagnostic value of SPECT imaging following a conventional planar imaging. Forty-three femoral heads in twenty-six cases with idiopathic femoral head necrosis (n=2), systemic lupus erythematosus (n=22), aplastic anemia (n=1), and renal transplantation (n=1) were studied. The diagnosis for femoral head necrosis was based on magnetic resonance imaging as well as other diagnostic studies in all cases. Scintigraphic findings of planar and SPECT images were classified into six categories: normal (N); cold or decrease (C); partial increase with cold or decrease (PH+C); ring-like increase with a cold center (RH+C); partial increase (PH); diffuse and/or irregular increase (DH). Avascular necrosis was confirmed in twenty-four femoral heads, in which planar and SPECT images showed scintigraphic findings of N (n=3, 2), C (n=1, 3), PH+C (n=2, 8), RH+C (n=2, 3), PH (n=9, 2), and DH (n=7, 6), respectively. Femoral heads without avascular necrosis demonstrated planar and SPECT findings of N (n=16, 12), C (n=0, 6), and DH (n=3, 1), respectively. When considering C, PH+C, and RH+C as diagnostic findings for avascular necrosis, sensitivities of planar and SPECT images were 21% and 58%, and specificities were 100% and 68%, respectively. In nineteen femoral heads with normal planar findings (N), SPECT correctly identified avascular necrosis in two femoral heads and misidentified six normal femoral heads as avascular necrosis. In nineteen femoral heads with nondiagnostic abnormalities (PH, DH), SPECT correctly identified avascular necrosis in seven femoral heads and showed no false positive. Diagnostic planar findings in five femoral heads were concordant with SPECT diagnosis. These results indicate that SPECT imaging is most valuable when planar images show nondiagnostic abnormalities based on the proposed classification of scintigraphic findings. (author)

  6. Statistical and heuristic image noise extraction (SHINE): a new method for processing Poisson noise in scintigraphic images

    International Nuclear Information System (INIS)

    Hannequin, Pascal; Mas, Jacky

    2002-01-01

    Poisson noise is one of the factors degrading scintigraphic images, especially at low count level, due to the statistical nature of photon detection. We have developed an original procedure, named statistical and heuristic image noise extraction (SHINE), to reduce the Poisson noise contained in the scintigraphic images, preserving the resolution, the contrast and the texture. The SHINE procedure consists in dividing the image into 4 x 4 blocks and performing a correspondence analysis on these blocks. Each block is then reconstructed using its own significant factors which are selected using an original statistical variance test. The SHINE procedure has been validated using a line numerical phantom and a hot spots and cold spots real phantom. The reference images are the noise-free simulated images for the numerical phantom and an extremely high counts image for the real phantom. The SHINE procedure has then been applied to the Jaszczak phantom and clinical data including planar bone scintigraphy, planar Sestamibi scintigraphy and Tl-201 myocardial SPECT. The SHINE procedure reduces the mean normalized error between the noisy images and the corresponding reference images. This reduction is constant and does not change with the count level. The SNR in a SHINE processed image is close to that of the corresponding raw image with twice the number of counts. The visual results with the Jaszczak phantom SPECT have shown that SHINE preserves the contrast and the resolution of the slices well. Clinical examples have shown no visual difference between the SHINE images and the corresponding raw images obtained with twice the acquisition duration. SHINE is an entirely automatic procedure which enables halving the acquisition time or the injected dose in scintigraphic acquisitions. It can be applied to all scintigraphic images, including PET data, and to all low-count photon images

  7. Stress fractures of the humerus, radius, and tibia in horses: clinical features and radiographic and/or scintigraphic appearance

    International Nuclear Information System (INIS)

    Mackey, V.S.; Trout, D.R.; Meagher, D.M.; Hornof, W.J.

    1987-01-01

    The medical records, radiographic and nuclear scintigraphic findings of 26 racing horses with 27 stress fracture episodes of the humerus, radius, or tibia were reviewed. The purposes of this study were to describe the radiographic and/or scintigraphic features of stress fractures of the humerus, radius, or tibia, and to evaluate the signalment and history of horses in which stress fracture occurred. Stress fractures of the three long bones examined were primarily seen in 2- and 3-year-old male Thoroughbred horses; commonly, the onset of lameness was immediately following training gallops or racing. There were 13 humeral stress fracture episodes in 12 horses. Ten were in the proximal caudolateral cortex, and three were in the distal craniomedial cortex. Radical stress fractures were seen in three horses, all in the midshaft radius. Tibial stress fractures were diagnosed in 11 horses. They were located in the proximal lateral tibia in six horses, the distal caudolateral tibia in three horses, and the midshaft tibia in three horses. Fifteen stress fractures were diagnosed with radiography alone, one was diagnosed with scintigraphy alone, nine were diagnosed with radiographs and scintigraphy, and, in two horses, radiographs were negative, but the scintigraphic findings were consistent with stress fracture

  8. Correlation between radiological, scintigraphic and histological changes in bone in rabbits following irradiation with single and fractionated doses

    International Nuclear Information System (INIS)

    Burgener, F.A.; King, M.A.; Weber, D.A.

    1979-01-01

    In the left hind legs of eight rabbits were irradiated with 1,750 rad in a single dose or with 4,650 rad divided over a period of three weeks. These animals, as well as four who had not been irradiated, were examined periodically radiologically and with 99 mTechnetium pyrophosphate scintigrams during one year. No difference could be detected between the results of the single and fractionated doses. Scintigraphically there was a biphasic increase in uptake, the first peak co-inciding with the irradiation and of vascular origin, whereas the second peak occured at four months and was due to a change in bone metabolism. At the end of a year uptake in the irradiated limb was slightly reduced. The earliest radiological changes were found after six months, at the end of the second scintigraphic peak; they consisted of coarsening and blurring of the trabeculae, non-homogeneous spotty mineralisation and endosteal scalloping. Six animals developed a radiation-induced bone sarcoma, first demonstrated either by scintigraphy or radiology depending on its histology. The value of combining radiological and scintigraphic examinations for the early detection of post-radiation abnormalities is stressed. (orig.) [de

  9. 27 CFR 4.2 - Territorial extent.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Territorial extent. 4.2 Section 4.2 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS LABELING AND ADVERTISING OF WINE Scope § 4.2 Territorial extent. This part...

  10. A proposal to study the esophageal transit by biomagnetic and scintigraphic study

    International Nuclear Information System (INIS)

    Daghastanli, N.A.; Braga, F.J.H.N.; Baffa, O.

    1996-01-01

    The initial results for a new apparatus to study the esophageal transit time is studied in asymptomatic persons for a yogurt bolus (10 ml). The bolus is uniformly labeled with 5 g of ferrite powder (biomagnetic study, B) or 350 MBq of 99m Tc (scintigraphic study, C). For the B study the detection is made by means two pair of coils in opposite phase excited by a 10 k Hz sinusoidal voltage. The signal response is obtained when the bolus traverses the coils placed on the regions-of-interest (ROIs) of the esophagus (furcula, F and xiphoid process, X) and produces a signal voltage that is measured by a lock-in amplifier Stanford SR530. For C studies an Orbiter Siemens scintillation camera is used linked to a computer. The data analysis shows a (4.1±0.7)s in B studies and (3.7±0.9)s in C studies (R=0.6, P<0.07)

  11. Sacroiliitis detected by bone scintiscanning: a clinical, radiological, and scintigraphic follow-up study

    International Nuclear Information System (INIS)

    Chalmers, I.M.; Lentle, B.C.; Percy, J.S.; Russell, A.S.

    1979-01-01

    Twenty-four patients had abnormal sacroiliac joints detected by quantitative sacroiliac scintigraphy but no radiological evidence of sacroiliitis on original investigation. They were studied again after intervals of 12 to 36 months. Four patients developed radiological change. Two young, HLA B27-positive men had undoubted ankylosing spondylitis, and a young woman had possible ankylosing spondylitis. A middle-aged man had changes that could be attributed to post-traumatic osteoarthrosis. Of the remaining 20 cases, 15 had symptoms and signs suggestive of inflammatory disease of the axial skeleton (and peripheral arthropathy in 5 cases). The sexes were affected equally (8 females, 7 Males), and only 2 of the 15 were B27-positive. The response to anti-inflammatory medication was generally good to excellent, and scintiscans tended to improve. Of the remaining 5 patients, 3 had mechanical or traumatic problems, and in 2 there was no explanation for the abnormal sacroiliac scintiscan. It is concluded that quantitative sacroiliac scintigraphy may detect ankylosing spondylitis prior to the development of radiological change and that it can identify an organic basis for backache in patients with a spondylitis-like syndrome. The clinical circumstances must be taken into account, as scintigraphic abnormalities are not diagnostic of any specific disease entity. (author)

  12. Detection and localization of lower gastrointestinal bleeding site with scintigraphic techniques

    International Nuclear Information System (INIS)

    Alavi, A.

    1988-01-01

    Successful management of acute gastrointestinal (GI) bleeding frequently depends on accurate localization of the bleeding site. History and clinical findings are often misleading in localizing the site of hemorrhage. The widespread application of flexible endoscopy and selective arteriography now provides accurate diagnoses for the majority of patients with upper GI tract hemorrhage, but lower GI bleeding still is a serious diagnostic problem. Endoscopy and barium studies are of limited value in examining the small bowel and colon in the face of active hemorrhage. Arteriography, although successful in many cases, has limitations. The angiographic demonstration of bleeding is possible only when the injection of contrast material coincides with active bleeding. Since lower GI bleeding is commonly intermittent rather than continuous, a high rate of negative angiographic examinations has been reported. Repeated angiography to pursue recurrent episodes of bleeding is impractical. Because of these shortcomings, in the past decade several noninvasive scintigraphic techniques have been developed to detect and localize sites of GI bleeding. In this chapter the authors discuss details related to the technetium 99m sulfur colloid (Tc-SC) and technetium 99m-labeled red blood cell (Tc-RBC) techniques

  13. Scintigraphic examinations after stent implantation in central airways; Szintigraphische Untersuchungen bei Stents in den zentralen Atemwegen

    Energy Technology Data Exchange (ETDEWEB)

    Richter, W.S.; Kettner, B.I.; Munz, D.L. [Klinik und Poliklinik fuer Nuklearmedizin, Universitaetsklinikum Charite, Medizinische Fakulteat der Humboldt-Univ. zu Berlin (Germany)

    1998-03-01

    Endotracheal and endobronchial stent implantation has been developed as an effective treatment of benign and malignant airway stenosis and of tracheo- or bronchoesophageal fistulas. The selection of the stent type depends on the kind and site of disease. Chest X-ray and bronchoscopy are the procedures of choice for monitoring of stent position, structure, and function. However, with scintigraphic methods the effects of stent implantation on pulmonary ventilation and perfusion can be assessed non-invasively. The validation of the effect of a stent implantation on mucociliary and tussive clearance remains to be elucidated. (orig.) [Deutsch] Die endotracheale und -bronchiale Stentimplantation wurde in den letzten Jahren als effektive Massnahme bei benignen und malignen Stenosen der Atemwege, drohendem Atemwegsverschluss und bei tracheo- bzw. bronchooesophagealen Fisteln eingefuehrt. Der gewaehlte Stenttyp richtet sich nach dem Implantationsort und den krankheitsbedingten Veraenderungen. Zum Monitoring von Lage, Struktur und Funktion eines Stents dienen Thoraxroentgenaufnahmen und die Bronchoskopie. Nuklearmedizinische Verfahren koennen nicht-invasiv den Effekt der Stenteinlage auf Lungenventilation und -perfusion belegen. Die Validierung des Effekts einer Stentimplantation auf die mukoziliaere und tussive Clearance steht noch aus. (orig.)

  14. Time course of transient cortical scintigraphic defects associated with acute pyelonephritis

    Energy Technology Data Exchange (ETDEWEB)

    Ditchfield, Michael R.; Summerville, Dianne; Cook, David J.; Campo, John F. de [Department of Radiology, Royal Children' s Hospital, Melbourne 3052 (Australia); Grimwood, Keith; Nolan, Terrance M. [Department of General Paediatrics, Royal Children' s Hospital, Melbourne (Australia); Department of Paediatrics, University of Melbourne, Melbourne (Australia); Powell, Harley R. [Department of Nephrology, Royal Children' s Hospital, Melbourne (Australia); Sloane, Robert [Department of General Paediatrics, Royal Children' s Hospital, Melbourne (Australia)

    2002-12-01

    Acute pyelonephritis is distinguished from renal scarring using repeat cortical scintigraphy. The defects of acute pyelonephritis resolve, while those of scars persist. To determine the duration of reversible cortical defects following acute pyelonephritis and the time interval required to differentiate infection from scars. Materials and methods. An observational prospective study of 193 children (386 kidneys) aged less than 5 years following their first proven urinary tract infection (UTI). Renal cortical scintigraphic defects were detected in 112 (29%) kidneys within 15 days of diagnosis. Of these, 95 underwent repeat renal cortical scans 2 years after the UTI, including 50 with additional scans performed within 2-6 months of infection. Of the 50 kidneys undergoing a second renal cortical scan within 2-6 months of the first UTI, 22 (44%) had persistent defects. A third scan was performed on 17 (77%) kidneys after 2 years, by which time defects had resolved in another 8 (47%) kidneys. The predictive value of defects detected within 2-6 months of UTI representing scars is 53% (95% CI 28, 77). Overall, nine (18%) kidneys with initial renal cortical abnormalities had permanent defects. In the 45 kidneys undergoing a second cortical scan more than 6 months after the UTI, 11 (24%) had persistent defects. None of the 95 kidneys undergoing serial scans developed new or larger defects. Renal scars may not be reliably diagnosed by cortical scintigraphy performed within 6 months of UTI because the inflammatory lesions may not have fully resolved. (orig.)

  15. Usefulness of renal scintigraphic scanning in the prognosis of acute renal failure

    International Nuclear Information System (INIS)

    Bernheim, J.; Collard, M.; Westphall, M.; Guey, A.; Traeger, J.

    1976-01-01

    The first results concerning the use of renal scintigraphic scanning using hippuran in acute renal failure (A.R.F.) are presented. The tubular stages of hippuran, extraction and secretion then excretion correspond to phenomena which are normally apparent within the first 10 minutes following the injection of hippuran, also it seemed interesting to study the changes which occur in A.R.F. 18 hospital in-patients with A.R.F. were studied, 10 of them suffering from tubulo-interstitial nephropathy (T.I.N.) 4 with acute glomerulonephritis (A.G.N.), 2 with obstruction of the urinary pathways and 2 with tubular necrosis on underlying chronic renal failure. In the 10 cases of T.I.N. the phenomenon of extraction was evident without any sign of secretion appearing during the 24 minutes of the investigation. No relationship could be found between the scintigram and the rapidity of recovery from A.R.F., but 8/10 recovered satisfactory renal function, the two others died from their disease, the A.R.F. being only secondary. It seems that the presence of an extraction phenomenon, whatever the aetiology of the A.R.F., is a parameter which authorizes the prognosis of a favorable course whereas its absence during the 24mm, of the investigation permits one to envisage an unfavorable course [fr

  16. 3D tomographic imaging with the γ-eye planar scintigraphic gamma camera

    Science.gov (United States)

    Tunnicliffe, H.; Georgiou, M.; Loudos, G. K.; Simcox, A.; Tsoumpas, C.

    2017-11-01

    γ-eye is a desktop planar scintigraphic gamma camera (100 mm × 50 mm field of view) designed by BET Solutions as an affordable tool for dynamic, whole body, small-animal imaging. This investigation tests the viability of using γ-eye for the collection of tomographic data for 3D SPECT reconstruction. Two software packages, QSPECT and STIR (software for tomographic image reconstruction), have been compared. Reconstructions have been performed using QSPECT’s implementation of the OSEM algorithm and STIR’s OSMAPOSL (Ordered Subset Maximum A Posteriori One Step Late) and OSSPS (Ordered Subsets Separable Paraboloidal Surrogate) algorithms. Reconstructed images of phantom and mouse data have been assessed in terms of spatial resolution, sensitivity to varying activity levels and uniformity. The effect of varying the number of iterations, the voxel size (1.25 mm default voxel size reduced to 0.625 mm and 0.3125 mm), the point spread function correction and the weight of prior terms were explored. While QSPECT demonstrated faster reconstructions, STIR outperformed it in terms of resolution (as low as 1 mm versus 3 mm), particularly when smaller voxel sizes were used, and in terms of uniformity, particularly when prior terms were used. Little difference in terms of sensitivity was seen throughout.

  17. Results of Chiari pelvic osteotomy for acetabular dysplasia in adults; Association with bone scintigraphic findings

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Nobuo; Ozono, Kenji; Sugano, Nobuhiko; Takaoka, Kunio; Ono, Hiroo (Osaka Univ. (Japan). Faculty of Medicine)

    1993-02-01

    In an attempt to determine indications of Chiari pelvic osteotomy in acetabular dysplasia, postoperative outcome of hip joint (64 joints) was examined on the basis of findings of bone scintigraphy. The subjects were 61 patients with osteoarthrosis of hip joint who underwent preoperative bone scintigraphy. The follow-up period ranged from 2 years to 9 years and 7 months with a mean of 4 years and 9 months. According to X-ray findings, 37 osteoarthrosis joints were staged as early and 27 as progressive. Preoperative bone scintigraphic findings fell into three: (I) normal or slight hot type (33 joints), (II) hot type at the weighting part (16 joints), and (III) double hot type in the weighting part and inside part (15 joints). None of the patients had severe surgical complications such as deep-seated infection, neuroparalysis and pseudojoint. According to the clinical staging for hip joint function, 7 (47%) of 64 joints were judged as poor after osteotomy, belonging to type III. Deterioration of osteoarthrosis was seen in 11 joints (41%) on X-ray films. Of these, 9 had type III. In conclusion, Chiari pelvic osteotomy should not be indicated when type III is shown on bone scintigrams. (N.K.).

  18. Scintigraphic appearance of focal fatty infiltration of the liver using single-photon emission computed tomography

    International Nuclear Information System (INIS)

    Kudo, M.; Hirasa, M.; Ibuki, Y.

    1984-01-01

    Fatty infiltration of the liver had been considered to assume a uniform distribution until quite recently. However, the development of X-ray computed tomography (XCT) and the ultrasound (US) has proven that fatty infiltration of the liver may sometimes assume a nonuniform distribution (focal fatty infiltration (FFI)). This investigation was undertaken to evaluate the scintigraphic appearance of FFI using single-photon emission computed tomography (SPECT) with a GE Maxicamera 400T. Radionuclide images including SPECT were evaluated in 12 cases with FFI which were diagnosed by XCT and US. Most of them were histrogically confirmed to be positive fatty infiltration in the liver. The results were as follows. The fatty infiltrated area was visualized as a hot spot in one case, a defect in 2 cases, a low uptake in one case and a normal uptake in 8 cases. Radionuclide imaging of FFI shows a large variety of findings and it suggests that Kupffer cell function varies with the causes or stage of fatty infiltration. And one can understand the pathological state of FFI from a viewpoint of Kupffer cell function only by radionuclide imaging including SPECT, which is very useful to compare the images with XCT images

  19. Scintigraphic evaluation of brain death with 99mTc-d,l-hexamethyl-propyleneamine oxime (HMPAO)

    International Nuclear Information System (INIS)

    Takehara, Yasuo; Isoda, Haruo; Sakai, Tsuneo; Tanaka, Tokutaro; Sato, Haruhiko; Yamamoto, Takamichi; Takahashi, Motoichiro; Kaneko, Masao.

    1989-01-01

    Lately, the criteria of brain death is being discussed. Cerebral scintigram, especially scintigraphic evaluation of brain death by dynamic study, has been previously reported. Cerebral imaging using radiolabeled amines such as 123 I-IMP N-isopropyl-p-iodoamphetamin (IMP) or 99m Tc d, l-hexamethyl-propyleneamine oxime (HMPAO) offers a significant information of brain death by the finding of 'non visualized brain'. However, the dynamic scintigram acquired during the bolus injection of 99m Tc-HMPAO provides an additional information of brain death by classical 'hot nose sign'. 99m Tc-HMPAO is able to be administered relatively in a large amount of dose. This cerebral perfusion tracer is lipophilic and remains in the central nervous system, which characterize its role as a reliable indicator of cerebral blood flow. As a result, this compound became suitable for the non-invasive study of brain circulation when the diagnosis of brain death is uncertain. We report a case of brain death in which diagnosis was made by the classical 'hot nose sign' in dynamic scintigraphy performed when 99 mTc-HMPAO was injected as well as the SPECT which showed a lack of cerebral visualization at the equilibrium state. As far as we are informed, this additional procedure used in the diagnosis of brain death has not reported before. The importance of performing a dynamic scintigram at the administration of 99m Tc-HMPAO is also discussed in this report. (author)

  20. Scintigraphic acquisition entropy (2). A new approach in the quality control of the scintillation camera performances

    International Nuclear Information System (INIS)

    Elloumi, I.; Bouhdima, M.S.

    2002-01-01

    A new approach in the survey of the performances of gamma camera based on the entropy associated to the scintigraphic acquisition is presented. We take into account the sensitivity, the variation of the collimator response in function of the depth, the uncertainty on the number of counts, the multiplex effect and the spatial uncertainty. This entropy function is expressed in function of all the acquisition parameters: intrinsic crystal resolution, collimator characteristics, emitter object parameters and the source activity. The application of this method to the study of the influence of the collimation shows that the entropy associated to a collimator permits a best appreciation of the quality of the acquisition and therefore a better analysis of collimator performances. Likewise, the evolution of the entropy associated to the acquisition of a uniform source image is in agreement with the variation of the quality of image histogram. One shows, thus, that nor the spatial resolution, nor the sensitivity and nor the signal to noise ratio are able detect a variation of the image quality, when analysed one by one. (author)

  1. Interest of scintigraphic imaging in Madagascar for the diagnosis of ectopic parathyroid adenoma, about one case

    International Nuclear Information System (INIS)

    Andriantsoa, J.; Andriamanalina, T.; Ramamonjy, A.; Ranivontsoarivony, M.; Ramahandridona, G.; Razafindramboa, H.; Gizy Ratiambahoaka, D.

    2008-01-01

    This study reports the first case of ectopic parathyroid adenoma, diagnosed in the Department of Nuclear Medicine in Antananarivo. This clinical vignette illustrates the interest of the MIBI-Tc-99 m scan in locating this adenoma and its diagnostic confirmation after six years of erratic diagnosis. A whole body bone scintigraphy has also allowed to assess the state of bone metabolism and study outbreaks of fracture. The parathyroid scintigraphy was carried out after intra-venous administration of 666 MBq of MIBI- 99m Tc. Dynamic images, static early and late static were acquired with a gamma camera E-Cam Siemens. The whole body bone scan was carried out after administration of 555 MBq of M.D.P.-Tc-99 m. The results evidenced the presence of an para-aortic increased uptake area pointing to a left parathyroid adenoma. The persistence of a late left sub maxillary increased uptake area raises, however, a reservation about the existence of a second adenoma. The bone scan displayed global skeletal remodeling, non suggestive of metastases, as it was mentioned with the CT-scan. In a diagnostic tools limited environment, skeletal pain refractory to pain-killers, a chronic hypercalcemia associated with an increased parathyroid hormone level, should trigger the scintigraphic exploration in order to avoid bone and renal complications

  2. Scintigraphic evaluation of chronic cholecystitis with cholelithiasis using technetium-99m-labelled pyridoxylidene isoleucine

    International Nuclear Information System (INIS)

    Alp, E.; Bekdik, C.F.; Laleli, Y.; Ercan, M.T.

    1981-01-01

    Technetium-99m-labelled pyridoxylidene isoleucine was evaluated in normal subjects as a hepatobiliar scanning agent and in patients with chronic cholecystitis with cholelithiasis. In all the normals and patients the liver function tests (SGOT, SGPT, AP and serum bilirubin) were normal. Scintigraphic studies were performed at 5, 10, 15, 20, 25, 30 and 60 min after IV administration of the agent. In the normal group (seven subjects) liver was visualized at 5 min, the common bile duct and the gall bladder at 5-15 min and the bowel activity within 20 min. In the patient group (15 subjects) the liver and the common bile duct were visualized at the same time as in the normal group but the gall bladder was either visualized later or not at all. The results showed that chronic cholecystitis with cholelithiasis may be diagnosed with 87% accuracy using 99 Tcsup(m)-pyridoxylidene isoleucine cholescintigraphy. Scintigraphy with this agent has also superiority over roentgenologic examination in 20% of the cases. (author)

  3. Scintigraphic imaging with 99mTc- exorphin C in rabbits

    International Nuclear Information System (INIS)

    Ertay, T.; Uenak, P.; Tasci, C.; Zihnioglu, F.; Durak, H.

    2005-01-01

    Exorphin C is a peptide with five amino acids [(Tyr-Pro-Ile-Ser-Leu) Trifluoroacetate salt] (Sigma) that has an affinity to opioid receptor-expressing tissues and tumors. Exorphin-C was labeled with 99m Tc using glucoheptonate (GH) as bifunctional chelating agent. Then, we investigated its radiopharmaceutical potential as opioid receptor-expressing tissue on rabbits. Quality controls were performed by ITLC, paper electrophoresis and HPLC. Labeling efficiency was higher than 98%. The compound was stable for at least 5 h at room temperature. Scintigraphic imaging with 99m Tc-GH-exorphin C ( 99m Tc-GE) was performed on male Albino rabbits. Static images were obtained from anterior projection using a Camstar XR/T gamma camera at several time intervals. Although a significant amount of activity was seen in the brain, less activity was seen on receptor saturation studies at 30 min. Slight hepatobiliary excretion was seen, though the main excretion route was renal. After saturating, the receptor hepatobiliary excretion was not seen; the only excretion route was renal

  4. Gastric emptying and intragastric distribution of lipids in man. A new scintigraphic method of study

    International Nuclear Information System (INIS)

    Jian, R.; Vigneron, N.; Najean, Y.; Bernier, J.J.

    1982-01-01

    We measured gastric emptying of fat and water from a solid-liquid meal in healthy volunteers using a tubeless scintigraphic method. 75 Se glycerol triether, incorporated in butter, was the lipid-phase marker, and /sup 99m/Tcm, ingested with 250 ml water, the non-lipid phase marker. In seven of these subjects we also measured the gastric emptying of solids and liquids with /sup 99m/Tc bound to cooked egg whites as the solid-phase marker and 111 In ingested with 250 ml water as the marker of the solid and aqueous phases. Emptying and intragastric repartition of each marker were measured by detection of radioactivity changes over the abdominal area using a gamma-camera. The stability and the specificity of the labeling was checked for each marker. Mean gastric emptying rate (expressed as percentage ingested marker emptied per hr) of lipids (17.4 +/- 2.4) was much lower than that of the rest of the meal (34.2 +/- 1.8) and slightly, but significantly, lower than that of solids (22.8 +/- 1.8). An intragastric layering of fat above nonlipids was observed only after the first postprandial hour and remained moderate. Thus, lipids are emptied more slowly than any other component of an ordinary meal, and this is not due only to layering of fat above water

  5. Correlation of hepatospleno-scintigraphic findings with HBe antigenicity in chronic hepatitis B

    Energy Technology Data Exchange (ETDEWEB)

    Song, K S; Chun, K S; Chung, S K; Bahk, Y W [Catholic Medical College, Seoul (Korea, Republic of)

    1983-12-15

    Radioimmunoassay plays an important role in diagnosing the hepatitis B and in clinical assessment of the course of the disease as well. Among a number of antigens, antibodies and enzymes related with hepatitis, HBe Ag, DNA polymerase, IgM-HBc-antibody, {delta} Ag have been known as useful indicators of ongoing infectivity of hepatitis B. The present study has been undertaken to correlate the HBe antigenicity with hepatospleno-scintigraphic findings in hepatitis. The study covered a 10 month period from September 1982 through to July 1983. We reviewed and analyzed the hepatospeno-scintgraphic findings and the results of radioimmuassays in 32 patients of chronic hepatitis seen at St. Mary Hospital, Catholic Medical College. Hepatitis B was diagnosed either when HBs Ag was positive or Anti-HBc wa positive even if HBs Ag was negative. We classified the HBe antigenicity into two groups of HBe Ag(+) and HBe(-) and analyzed the scintgraphic findings in terms of liver size, motting, splenomegaly and splenic shift. From the present study, it is concluded that the activity of hepatitis B can not be assessed by the findings of hepatospleno-scintigram so far as the activity is determined on the basis of the positive HBe Ag, which has been believed to indicated continuing viral replication.

  6. Gastric emptying and intragastric distribution of lipids in man. A new scintigraphic method of study

    Energy Technology Data Exchange (ETDEWEB)

    Jian, R.; Vigneron, N.; Najean, Y.; Bernier, J.J.

    1982-08-01

    We measured gastric emptying of fat and water from a solid-liquid meal in healthy volunteers using a tubeless scintigraphic method. /sup 75/Se glycerol triether, incorporated in butter, was the lipid-phase marker, and /sup 99m/Tcm, ingested with 250 ml water, the non-lipid phase marker. In seven of these subjects we also measured the gastric emptying of solids and liquids with /sup 99m/Tc bound to cooked egg whites as the solid-phase marker and /sup 111/In ingested with 250 ml water as the marker of the solid and aqueous phases. Emptying and intragastric repartition of each marker were measured by detection of radioactivity changes over the abdominal area using a gamma-camera. The stability and the specificity of the labeling was checked for each marker. Mean gastric emptying rate (expressed as percentage ingested marker emptied per hr) of lipids (17.4 +/- 2.4) was much lower than that of the rest of the meal (34.2 +/- 1.8) and slightly, but significantly, lower than that of solids (22.8 +/- 1.8). An intragastric layering of fat above nonlipids was observed only after the first postprandial hour and remained moderate. Thus, lipids are emptied more slowly than any other component of an ordinary meal, and this is not due only to layering of fat above water.

  7. The significance of 123I-BMIPP delayed scintigraphic imaging in cardiac patients.

    Science.gov (United States)

    Akashi, Yoshihiro J; Kida, Keisuke; Suzuki, Kae; Inoue, Koji; Kawasaki, Kensuke; Yamauchi, Masahiro; Musha, Haruki; Anker, Stefan D

    2007-04-25

    Earlier studies have not fully investigated the significance of radionuclide planar imaging in cardiac patients using the fatty acid analogue 123I-beta-methyl-iodophenylpentadecanoic acid (123I-BMIPP). This study was to clarify the effectiveness of 123I-BMIPP in assessing the heart-to-mediastinum ratio (H/M) and myocardial washout rate (WR) in patients with heart disease. Myocardial 123I-BMIPP imaging was performed in 33 patients (20 with chronic heart failure [CHF] and 13 with stable angina pectoris [AP]) and 11 control subjects. Myocardial 123I-BMIPP planner images were obtained 30 min (early image) and 4 h (delayed image) after tracer injection. The left ventricular ejection fraction (LVEF) was measured by quantitative gated single photon emission computed tomography. The concentration of plasma brain natriuretic peptide (BNP) was measured before the scintigraphic study. (1) Delayed H/M was much lower in CHF than in AP (1.93 +/- 0.37 vs. 2.21 +/- 0.38, p acid metabolism disorders in patients with heart disease in both masked and unmasked conditions.

  8. Correlation of hepatospleno-scintigraphic findings with HBe antigenicity in chronic hepatitis B

    International Nuclear Information System (INIS)

    Song, K. S.; Chun, K. S.; Chung, S. K.; Bahk, Y. W.

    1983-01-01

    Radioimmunoassay plays an important role in diagnosing the hepatitis B and in clinical assessment of the course of the disease as well. Among a number of antigens, antibodies and enzymes related with hepatitis, HBe Ag, DNA polymerase, IgM-HBc-antibody, δ Ag have been known as useful indicators of ongoing infectivity of hepatitis B. The present study has been undertaken to correlate the HBe antigenicity with hepatospleno-scintigraphic findings in hepatitis. The study covered a 10 month period from September 1982 through to July 1983. We reviewed and analyzed the hepatospeno-scintgraphic findings and the results of radioimmuassays in 32 patients of chronic hepatitis seen at St. Mary Hospital, Catholic Medical College. Hepatitis B was diagnosed either when HBs Ag was positive or Anti-HBc wa positive even if HBs Ag was negative. We classified the HBe antigenicity into two groups of HBe Ag(+) and HBe(-) and analyzed the scintgraphic findings in terms of liver size, motting, splenomegaly and splenic shift. From the present study, it is concluded that the activity of hepatitis B can not be assessed by the findings of hepatospleno-scintigram so far as the activity is determined on the basis of the positive HBe Ag, which has been believed to indicated continuing viral replication

  9. Scintigraphic study of palpable breast nodes with 99m Tc-tetrofosmin

    International Nuclear Information System (INIS)

    Pellini, Marcos Pinto; Fonseca, Lea Mirian Barbosa da; Amarante Junior, Jose Luiz de Medeiros; Fabricio, Maria Ines Menescal

    1998-01-01

    In Brazil, breast carcinoma has the greater incidence among women. In 1996, about 31,210 new cases were diagnosed. The purpose of this study is to determine if 99m technetium-tetrofosmin preferentially concentrates within malignant palpable breast nodes, distinguishing them from the benign lumps. Fifth-four consecutive and unsolicited women, mean age 47.5 +- 10.7 years, with palpable nodes in breast, underwent breast scintigraphy with 99m technetium-tetrofosmin and excisional biopsy or fine needle puncture within interval eight weeks. Histopathologic studies demonstrated 13 cysts, 1 cyst with local inflammation, 11 fibroadenoma, 2 fibrodysplasias, 3 fibroadenomas with high cellularity, 1 fibrocystic change with local inflammation, 23 invasive intraductal carcinomas and 1 invasive lobular carcinoma. The nodes ranged from 10 to 100 mm in greater diameter. The scintigraphic study yielded 30 true-negative cases, 24 true-positives, no false-negative and 1 false-positive. This case was a fibrocystic lump with local inflammation. Two patients had metastases in axillary lymph nodes, well detected in scintigraphy. The statistic analysis showed: sensitivity, 100%; specificity, 96.8%; accuracy, 98.2%; negative predictive value, 100%; positive predictive value, 96.0%. Nonparametric tests of Fisher and Chi-square rejected the antithesis at a confidence interval of 99.9% (p 99m technetium-tetrofosmin preferentially concentrates in malignant palpable breast nodes and can help to distinguish them from the benign tumors with with very high accuracy. (author)

  10. Assessment of scintigraphic image quality in Single Photon Emission Computed Tomography (SPECT) using jaszczak phantom

    International Nuclear Information System (INIS)

    Eduful, E. K

    2012-01-01

    The image quality of scintigraphic images has been improved by applying a MatLab algorithm code and five different filters to an acquired image of the data spectrum (Jaszczak) phantom and the FWHM (resolution) values measured using ImageJ software. The average FWHM value recorded for the acquired image and the Matlab enhanced image were 14.246±0.205 mm and 11.609±1.458 mm respectively. The analyses performed on the acquired image showed improvements in its resolution. Combination of the MatLab algorithm code and the Trous-Wavelet filter gave the best improvement in resolution of the acquired image, with an average FWHM value of 10.261±1.381 mm. This indicates a 27.973% improvement in the FWHM value of the acquired image. The CLAHE filter, Kuwahara filter, Sigma filter Plus and filter rank, improved the resolution of the acquired image by 21.627%, 17.48%, 4.745% and 8.949% respectively. Results from the study indicate that the acquired image was improved in quality by applying the Matlab image enhancement tool and filters. The outcome of this study shows promise in aiding nuclear medicine physicians to make improved diagnostic decisions if applied to clinical cases.(au)

  11. Differentiation of scintigraphic-morphological changes of the thyroid by diffusion techniques

    International Nuclear Information System (INIS)

    Auf Hamada, T.

    1974-01-01

    The essay was based on the question of the possibility of obtaining a diagnostic parameter by determining the thyroidal blood circulation with the aid of gamma-camera examination. A series of confirmed cases of hyperthyreoses, adenomas, cycts, and malignomas was selected trying to distinguish the criteria of the blood circulation of clinically, serologically, and scintigraphically normal organs. The blood circulation of the normal-sized, or slightly enlarged thyroid showed in all cases a normal curve with constant increase, but without a peak during the period of examination (60 sec.). If we look at the curve in the case of hyperthyreosis, we see, in contrast to the normal findings a notably faster accumulation of the nuclide in the thyroid, with a slightly reduced enrichment in the further course of the examination, in comparison to the initial part of the curve. The blood circulation curves of decompensated adenomas show, in contrast to the compensated adenoma, also a faster initial accumulation, in relation to the total height of the impulse, which is quantitatively increased by 1/3. If we compare all adenomas, we see that the curve ascends continously, although only in two of seven cases a peak could be differentiated, which might be due to a faster thyroid clearance. (orig./AJ) [de

  12. Time course of transient cortical scintigraphic defects associated with acute pyelonephritis

    International Nuclear Information System (INIS)

    Ditchfield, Michael R.; Summerville, Dianne; Cook, David J.; Campo, John F. de; Grimwood, Keith; Nolan, Terrance M.; Powell, Harley R.; Sloane, Robert

    2002-01-01

    Acute pyelonephritis is distinguished from renal scarring using repeat cortical scintigraphy. The defects of acute pyelonephritis resolve, while those of scars persist. To determine the duration of reversible cortical defects following acute pyelonephritis and the time interval required to differentiate infection from scars. Materials and methods. An observational prospective study of 193 children (386 kidneys) aged less than 5 years following their first proven urinary tract infection (UTI). Renal cortical scintigraphic defects were detected in 112 (29%) kidneys within 15 days of diagnosis. Of these, 95 underwent repeat renal cortical scans 2 years after the UTI, including 50 with additional scans performed within 2-6 months of infection. Of the 50 kidneys undergoing a second renal cortical scan within 2-6 months of the first UTI, 22 (44%) had persistent defects. A third scan was performed on 17 (77%) kidneys after 2 years, by which time defects had resolved in another 8 (47%) kidneys. The predictive value of defects detected within 2-6 months of UTI representing scars is 53% (95% CI 28, 77). Overall, nine (18%) kidneys with initial renal cortical abnormalities had permanent defects. In the 45 kidneys undergoing a second cortical scan more than 6 months after the UTI, 11 (24%) had persistent defects. None of the 95 kidneys undergoing serial scans developed new or larger defects. Renal scars may not be reliably diagnosed by cortical scintigraphy performed within 6 months of UTI because the inflammatory lesions may not have fully resolved. (orig.)

  13. Real-time flood extent maps based on social media

    Science.gov (United States)

    Eilander, Dirk; van Loenen, Arnejan; Roskam, Ruud; Wagemaker, Jurjen

    2015-04-01

    During a flood event it is often difficult to get accurate information about the flood extent and the people affected. This information is very important for disaster risk reduction management and crisis relief organizations. In the post flood phase, information about the flood extent is needed for damage estimation and calibrating hydrodynamic models. Currently, flood extent maps are derived from a few sources such as satellite images, areal images and post-flooding flood marks. However, getting accurate real-time or maximum flood extent maps remains difficult. With the rise of social media, we now have a new source of information with large numbers of observations. In the city of Jakarta, Indonesia, the intensity of unique flood related tweets during a flood event, peaked at 8 tweets per second during floods in early 2014. A fair amount of these tweets also contains observations of water depth and location. Our hypothesis is that based on the large numbers of tweets it is possible to generate real-time flood extent maps. In this study we use tweets from the city of Jakarta, Indonesia, to generate these flood extent maps. The data-mining procedure looks for tweets with a mention of 'banjir', the Bahasa Indonesia word for flood. It then removes modified and retweeted messages in order to keep unique tweets only. Since tweets are not always sent directly from the location of observation, the geotag in the tweets is unreliable. We therefore extract location information using mentions of names of neighborhoods and points of interest. Finally, where encountered, a mention of a length measure is extracted as water depth. These tweets containing a location reference and a water level are considered to be flood observations. The strength of this method is that it can easily be extended to other regions and languages. Based on the intensity of tweets in Jakarta during a flood event we can provide a rough estimate of the flood extent. To provide more accurate flood extend

  14. Assessing the Global Extent of Rivers Observable by SWOT

    Science.gov (United States)

    Pavelsky, T.; Durand, M. T.; Andreadis, K.; Beighley, E.; Allen, G. H.; Miller, Z.

    2013-12-01

    Flow of water through rivers is among the key fluxes in the global hydrologic cycle and its knowledge would advance the understanding of flood hazards, water resources management, ecology, and climate. However, gauges providing publicly accessible measurements of river stage or discharge remain sparse in many regions. The Surface Water and Ocean Topography (SWOT) satellite mission is a joint project of NASA and the French Centre National d'Etudes Spatiales (CNES) that would provide the first high-resolution images of simultaneous terrestrial water surface height, inundation extent, and ocean surface elevation. Among SWOT's primary goals is the direct observation of variations in river water surface elevation and, where possible, estimation of river discharge from SWOT measurements. The mission science requirements specify that rivers wider than 100 m would be observed globally, with a goal of observing rivers wider than 50m. However, the extent of anticipated SWOT river observations remains fundamentally unknown because no high-resolution, global dataset of river widths exists. Here, we estimate the global extent of rivers wider than 50 m-100 m thresholds using established relationships among river width, discharge, and drainage area. We combine a global digital elevation model with in situ river discharge data to estimate the global extent of SWOT-observable rivers, and validate these estimates against satellite-derived measurements of river width in two large river basins (the Yukon and the Ohio). We then compare the extent of SWOT-observed rivers with the current publicly-available, global gauge network included in the Global Runoff Data Centre (GRDC) database to examine the impact of SWOT on the availability of river observation over continental and global scales. Results suggest that if SWOT observes 100 m wide rivers, river basins with areas greater than 50,000 km2 will commonly be measured. If SWOT could observe 50 m wide rivers, then most 10,000 km2 basins

  15. Scintigraphic detection of coronary artery thrombi in patients with acute myocardial infarction

    International Nuclear Information System (INIS)

    Fox, K.A.; Bergmann, S.R.; Mathias, C.J.; Powers, W.J.; Siegel, B.A.; Welch, M.J.; Sobel, B.E.

    1984-01-01

    To determine whether coronary thrombi can be detected scintigraphically after acute myocardial infarction, 24 patients were studied with a new method employing indium-111-labeled platelets and technetium-99m-labeled red blood cells. Nine patients with suspected infarction were evaluated initially within 9 hours of the onset of symptoms and again 18 to 24 hours after onset. Foci of net indium accumulation were detected after image processing that incorporated subtraction of blood pool activity. Carotid and pulmonary artery reference regions, in which blood pool activity is high and active platelet deposition unlikely, were used to correct digitized cardiac scintigrams for indium-111 platelet activity in the blood pool. In patients with infarction, distinct foci of net indium accumulation were present in regions corresponding to the coronary artery supplying ischemic zones. This occurred in seven of eight patients at the time of the earliest evaluation after the onset of symptoms) and in eight of nine patients at the time of subsequent imaging (23.6 +/- 1.9 hours after onset). Only 1 of 15 control patients exhibited a cardiac focus of net indium accumulation. The percent of indium excess (100 [total indium-111 activity-blood pool indium-111 activity]/blood pool indium-111 activity) within the cardiac region measured (+/- SD) 16.8 +/- 11.6% in all patients with myocardial infarction (19.1 +/- 11.2% in those with visually identified foci) compared with 0.4 +/- 4.3% in control patients. This method permits early detection and sequential assessment of coronary artery thrombi

  16. Leukocyte scintigraphy: correlation of serial scintigraphic findings and clinical progression of inflammatory bowel disease

    International Nuclear Information System (INIS)

    Ho, Y.; Kelly, M.J.; Kaliff, V.

    1997-01-01

    Full text: This study was performed (a) to determine whether the clinical progress of individual patients with inflammatory bowel disease mirrored changes in leukocyte scans, and (b) to assess the reasons for significant discrepancies. Two nuclear medicine physicians reviewed 44 white cell scans in 20 consecutive patients (4 males, 18 females) who were referred for two or more leukocyte scans (using either the 111 In Oxine or 99m Tc HMPAO labelling methods) by three gastroenterologists between 1 January 1992 and 1 June 1996. The sequential scanpairs (range 2-18 months apart) were classified by consensus reading as showing no change, more severe or less severe disease. Questionnaires were sent to the referring gastroenterologists to determine whether the overall clinical status of each patient was unchanged, better or worse in the interval between the two scans. There was complete agreement between clinical and scintigraphic assessment in 45% (10/22) of the study pairs. Review of responses of the three individual gastroenterologists showed a wide range of agreement (4/4, 4/5, 2/13). Review of data showed that most disagreement was based on subjective clinical assessment, and hence of uncertain significance. In two patients, however, potentially preventable false negative leukocyte scans occurred in patients with active proctitis. This may be overcome by rigorous attention to ensure complete emptying of radioactivity from the bladder when 99m Tc HMPAO is used. It was concluded that serial leukocyte scans add to clinical assessment but careful technique is needed to avoid false negative scans in the rectum

  17. Thermosetting gels with modulated gelation temperature for ophthalmic use: the rheological and gamma scintigraphic studies.

    Science.gov (United States)

    Wei, Gang; Xu, Hui; Ding, Ping Tian; Li, San Ming; Zheng, Jun Min

    2002-09-18

    For ophthalmic drug delivery, Pluronic F127 solutions have a phase transition temperature too low for them to be instilled into the eye at room temperature. Refrigerator storage is usually required to make administration easier, whereas the potential irritation of cold to the sensitive ocular tissues may result in poor topical bioavailability. The purpose of this study is to develop a thermosetting gel with a suitable phase transition temperature by combining Pluronic analogs and to examine the influence of incorporating mucoadhesive polysaccharide, sodium hyaluronate (HA-Na), on the ocular retention of the gel. Dynamic rheological method and single photon emission computing tomography (SPECT) technique were used to ex/in vivo evaluate the thermosetting gels, respectively. An optimized formulation containing 21% F127 and 10% F68 increased the phase transition temperature by 9 degrees C as evaluated by elasticity modulus compared to that of individual 21% F127 solution. Rheological behaviors of the Pluronic solutions showed that the combined Pluronic formulation was free flowing liquid below 25 degrees C and converted to a firm gel under the physiological condition. Furthermore, this formulation possessed the highest viscosity both before and after tear dilution at 35 degrees C. Gamma scintigraphic data demonstrated that the clearance of the thermosetting gel labeled with 99mTc-DTPA was significantly delayed with respect to the phosphate buffered solution, and at least a threefold increase of the corneal residence time was achieved. However, no further improvement in the ocular retention was observed when adding HA-Na into the thermosetting gel due to the substantially decreased gel strength. Copyright 2002 Elsevier Science B.V.

  18. Scintigraphic evaluation of osteoblastic activity in extraction sockets treated with platelet-rich fibrin.

    Science.gov (United States)

    Gürbüzer, Bahadir; Pikdöken, Levent; Tunali, Mustafa; Urhan, Muammer; Küçükodaci, Zafer; Ercan, Feriha

    2010-05-01

    To evaluate the effect of platelet-rich fibrin (PRF) on the early bone healing process with bone scintigraphy based on technetium-99m methylene diphosphonate uptake in third molar extraction sockets. Fourteen patients with bilaterally soft tissue impacted third mandibular molars were included in the study. The right and left impacted third molars were surgically extracted in the same session. PRF was randomly administered into one of the extraction sockets, whereas the contralateral sockets were left without treatment. Four weeks after surgery, scintigrams were obtained to evaluate scintigraphic differences between PRF-treated and non-PRF-treated sockets. After completion of the clinical study, PRF samples were evaluated by light and scanning electron microscopy. The average increase in technetium-99m methylene diphosphonate uptake as an indication of enhanced bone healing did not differ significantly between PRF-treated and non-PRF-treated sockets 4 weeks postoperatively (P > .05). Abundant fibrin and inflammatory cells were observed by light microscopic examination of PRF samples. Scanning electron microscopic analysis of PRF revealed the existence of platelet aggregates in a fibrin network and crystalline particles on the outer surface of PRF. PRF might not lead to enhanced bone healing in soft tissue impacted mandibular third molar extraction sockets 4 weeks after surgery. PRF exhibits the potential characteristics of an autologous fibrin matrix. However, whether the presence of crystal-like particles on the outer surface of PRF alters bone healing should be investigated further. Copyright 2010 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  19. Relevance of I-BMIPP delayed scintigraphic imaging for patients with angina pectoris - a pilot study.

    Science.gov (United States)

    Koyama, Kohei; Akashi, Yoshihiro J; Kida, Keisuke; Suzuki, Kengo; Ishibashi, Yuki; Musha, Haruki; Banach, Maciej

    2011-06-01

    The study was designed to clarify the role of (123)I-β-methyl-iodophenylpentadecanoic acid ((123)I-BMIPP) in the evaluation of myocardial fatty acid metabolism in patients with stable angina pectoris (AP) before and after percutaneous coronary intervention (PCI). TEN CONTROLS (MEAN AGE: 70.4 ±10.5 years) and 12 patients with AP (mean age: 67.4 ±11.6 years) and single vessel coronary artery disease participated in the radionuclide cardiac study. Scintigraphic images were acquired at 30 min and at 4 h after (123)I-BMIPP injection to determine early and delayed BMIPP uptake, respectively. The heart-to-mediastinum (H/M) ratio and the washout rate (WR) were calculated from the planar images. All patients underwent scintigraphy one day before PCI and again 1 month after successful PCI. NO SIGNIFICANT DIFFERENCES IN THE EARLY OR DELAYED H/M RATIOS WERE OBSERVED BETWEEN THE PATIENTS AND THE CONTROLS BEFORE PCI (EARLY: 2.70 ±0.36 vs. 2.73 ±0.57; delayed: 2.26 ±0.33 vs. 2.40 ±0.43; p > 0.2 for both). The early and delayed H/M ratios remained unchanged with the comparison with before PCI (early: 2.72 ±0.27, delayed: 2.23 ±0.22; p > 0.2 for both). The global WR before PCI was significantly higher in the patients than in the control group (36.7 ±9.3%, vs. 28.1 ±8.2%, p = 0.02). However, the WR after PCI did not significantly differ between the patients and the controls (34.3 ±7.8% vs. 28.1 ±8.2%, p = 0.1). These data may suggest that the WR of (123)I-BMIPP determined from the planar images enhances the presence of myocardial ischaemia.

  20. Comparison Of Dimercaptosuccinic Acid Scintigraphic And Voiding Cystourethrographic Findings In Patient With Acute Pyelonephritis

    Directory of Open Access Journals (Sweden)

    Fahimi P

    2003-11-01

    Full Text Available Acute Pyelonephritis (APN is one of the most common bacterial infections seen in children that may lead to renal scarring. Vesicoureteral reflux (VUR is an important risk factor of renal damage but not the only one. Materials and Methods: In order to determine the association between dimercaptosuccinic acid (DMSA scintigraphic and voiding cystourethrographic findings, a retrospective study was performed on 50 children (100 renal units with APN that had been admitted to Bahrami Hospital from 1995 through 1998. Voiding cystourethrography (VCUG and DMSA scan were performed in all patients within 1 to 2 weeks after termination of treatment and a second scan was performed 6 months later in patients whose kidneys showed cortical defects in the first one. The grade of reflux was based on international reflux classification (I-V. The DMSA scans were considered abnormal if one or more areas of decreased cortical uptake were noted (cortical defect. The scar was defined as persistence of these defects in the second scan. DMSA cortical defect and VUR were demonstrated in 42 (42% and 26 (26% of renal units respectively."nResults: Fourteen out of 26 renal units (54% with reflux had cortical defects and 28 out of 74 renal units (38% without reflux had cortical defects (P=0.15. Permanent renal scarring was noted in 25/ 42 of renal units (62 % in second scan. Conclusion: It seems that VCUG alone is insufficient as a screening modality to identity those kidneys at risk of damage and DMSA scan may provide additional information about this."n 

  1. Normal Values of Tissue-Muscle Perfusion Indexes of Lower Limbs Obtained with a Scintigraphic Method.

    Science.gov (United States)

    Manevska, Nevena; Stojanoski, Sinisa; Pop Gjorceva, Daniela; Todorovska, Lidija; Miladinova, Daniela; Zafirova, Beti

    2017-09-01

    Introduction Muscle perfusion is a physiologic process that can undergo quantitative assessment and thus define the range of normal values of perfusion indexes and perfusion reserve. The investigation of the microcirculation has a crucial role in determining the muscle perfusion. Materials and method The study included 30 examinees, 24-74 years of age, without a history of confirmed peripheral artery disease and all had normal findings on Doppler ultrasonography and pedo-brachial index of lower extremity (PBI). 99mTc-MIBI tissue muscle perfusion scintigraphy of lower limbs evaluates tissue perfusion in resting condition "rest study" and after workload "stress study", through quantitative parameters: Inter-extremity index (for both studies), left thigh/right thigh (LT/RT) left calf/right calf (LC/RC) and perfusion reserve (PR) for both thighs and calves. Results In our investigated group we assessed the normal values of quantitative parameters of perfusion indexes. Indexes ranged for LT/RT in rest study 0.91-1.05, in stress study 0.92-1.04. LC/RC in rest 0.93-1.07 and in stress study 0.93-1.09. The examinees older than 50 years had insignificantly lower perfusion reserve of these parameters compared with those younger than 50, LC (p=0.98), and RC (p=0.6). Conclusion This non-invasive scintigraphic method allows in individuals without peripheral artery disease to determine the range of normal values of muscle perfusion at rest and stress condition and to clinically implement them in evaluation of patients with peripheral artery disease for differentiating patients with normal from those with impaired lower limbs circulation.

  2. Scintigraphic Profile of Thyrotoxicosis Patients and Correlation with Biochemical and Sonological Findings.

    Science.gov (United States)

    Avs, Anil Kumar; Mohan, Abhish; Kumar, P G; Puri, Pankaj

    2017-05-01

    Thyrotoxicosis is a spectrum of disorder with a rather common clinical presentation with different aetiologies. The aetiological diagnosis is important as the management differs. It is essential to accurately diagnose the cause before starting treatment. Scintigraphy of thyroid helps in differentiating accurately the various causes. USG is routinely being advocated and T3/T4 ratio has also been used. This study aims to evaluate the scintigraphic profile of thyrotoxicosis patients and to correlate biochemical and USG findings with scintigraphy. A total of 60 newly diagnosed thyrotoxicosis patients based on biochemical reports were included in the study. They underwent further evaluation with ultrasonography and 99mTc scintigraphy. Of 60 patients of thyrotoxicosis, 45 cases were of Grave's disease, 10 cases were of thyroiditis and five cases were of Toxic Multinodular Goiter (MNG). The clinical characteristics were helpful in establishing the diagnosis in only six (10%) patients who presented with classic features of Grave's disease with ophthalmopathy. T3/T4 ratio greater than 20 was seen only in 29 (66%) patients of Grave's disease and also in three (33.33%) of thyroiditis patients. USG had a sensitivity and specificity of 81.82% and 93.75% in diagnosing Graves' disease and 100% and 82.4% in diagnosing thyroiditis respectively. Clinical findings do not help in accurately delineating aetiological diagnosis of thyrotoxicosis. Serum T3/T4 ratio when used as a criterion has marked overlap between the various conditions causing thyrotoxicosis. USG has reasonable sensitivity however, misses many cases of early Grave's disease. Follow up scintigraphy helps in a small population with resolving thyroiditis or early Grave's disease where the initial scintiscan is normal or inconclusive.

  3. Development of superior bone scintigraphic agent from a series of {sup 99m}Tc-labeled zoledronic acid derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Lin Jianguo [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063 (China); Qiu Ling, E-mail: qiulingwx@gmail.com [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063 (China); Cheng Wen [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063 (China); Luo Shineng, E-mail: shineng914@yahoo.com.cn [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063 (China); Xue Li; Zhang Shu [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063 (China)

    2012-05-15

    Two novel zoledronic acid (ZL) derivatives, 1-hydroxy-4-(1H-imidazol-1-yl)butane-1,1-diyldiphosphonic acid (IBDP) and 1-hydroxy-5-(1H-imidazol-1-yl)pentane-1,1-diyldiphosphonic acid (IPeDP), were prepared and labeled with the radionuclide technetium-99m in a high labeling yield. In vitro stabilities of these radiolabeled complexes were measured by the radio-HPLC analysis as a function of time, which showed excellent stability with the radiochemical purity of over 95% at 6 h post preparation. Their in vivo biological performances were evaluated and compared with those of {sup 99m}Tc-ZL and {sup 99m}Tc-MDP (methylenediphosphonic acid). The biodistribution in mice and scintigraphic images of the rabbit showed that the tracer agent {sup 99m}Tc-IPeDP had highly selective uptake in the skeletal system and rapid clearance from the blood and soft tissues and an excellent scintigraphic image can be obtained in a shorter time post injection with clear visualization of the skeleton and low soft tissue activity. These preclinical studies suggest that {sup 99m}Tc-IPeDP would be a novel superior bone scintigraphic agent. - Highlights: Black-Right-Pointing-Pointer Two novel diphosphonic acids were labeled with the {sup 99m}Tc in high labeling yield. Black-Right-Pointing-Pointer {sup 99m}Tc-IPeDP had high uptake in skeletal system and rapid clearance from blood. Black-Right-Pointing-Pointer {sup 99m}Tc-IPeDP reveals attractive biological features as superior bone scanning agent.

  4. Scintigraphic observation of the course of secondary fracture healing with and without ultrasonic stimulation in animal experiments

    International Nuclear Information System (INIS)

    Klug, W.; Franke, W.G.; Schulze, M.

    1986-01-01

    Secondary fracture healing was studied in the course of closed lower leg fractures in rabbit fracture models by /sup 99m/Tc scintiscanning. The ROI activity quotient increased significantly up to the maximum value, Q = 6.44 on the 14th day after fracture. 61 fractures of the lower leg were treated by ultrasonics from the 14th to the 28th day after fracture. These stimulated fractures showed a biologic healing already on the 168th day. Fractures untreated with ultrasonics could not be proved any more scintigraphically only after the 203rd day after fracture. (author)

  5. Application of a general-purpose scintigraphic scanner to transverse-section (tomographic) gamma-ray imaging

    International Nuclear Information System (INIS)

    Bradstock, P.A.; Milward, R.C.

    1976-01-01

    The paper describes the recent application of a general-purpose commercial scintigraphic scanner to transverse-section radioisotope tomography. The principle of the method is to obtain the distribution of radioactive material in a thin transverse slice of the body or brain, from a mathematical reconstruction using the measured transverse projections of the activity within that slice. The usefulness of the radioisotope section-scanning technique for clinical diagnosis, as evidenced from one year's use of the machine at the Midland Centre for Neurology and Neurosurgery, Birmingham, U.K., is briefly discussed. (orig.) [de

  6. Relevance of 123I-BMIPP delayed scintigraphic imaging for patients with angina pectoris ? a pilot study

    OpenAIRE

    Koyama, Kohei; Akashi, Yoshihiro J.; Kida, Keisuke; Suzuki, Kengo; Ishibashi, Yuki; Musha, Haruki; Banach, Maciej

    2011-01-01

    Introduction The study was designed to clarify the role of 123I-?-methyl-iodophenylpentadecanoic acid (123I-BMIPP) in the evaluation of myocardial fatty acid metabolism in patients with stable angina pectoris (AP) before and after percutaneous coronary intervention (PCI). Material and methods Ten controls (mean age: 70.4 ?10.5 years) and 12 patients with AP (mean age: 67.4 ?11.6 years) and single vessel coronary artery disease participated in the radionuclide cardiac study. Scintigraphic imag...

  7. Raccoon eyes and the MIBG super scan: scintigraphic signs of neuroblastoma in a case of suspected child abuse

    International Nuclear Information System (INIS)

    Bohdiewicz, P.J.; Gallegos, E.; Fink-Bennett, D.

    1995-01-01

    The authors report on an infant suspected of having been abused, who presented with periorbital edema and ecchymoses (clinial 'raccoon eyes'). The pattern of the nuclear medicine bone scan suggested neuroblastoma rather than trauma. Both the bone scan and the subsequent MIBG scan revealed multiple abnormalities, including markedly increased activity around the orbits, that we termed the 'scintigraphic raccoon eyes' sign. In addition, the grossly abnormal MIBG scan demonstrated avid uptake of MIBG throughout the entire skeleton with essentially complete absence of visualization of the liver and heart (the 'MIBG super scan'). These signs have not previously been described in an infant or a child with neuroblastoma. (orig.)

  8. Raccoon eyes and the MIBG super scan: scintigraphic signs of neuroblastoma in a case of suspected child abuse

    Energy Technology Data Exchange (ETDEWEB)

    Bohdiewicz, P.J. [Nuclear Medicine Dept., William Beaumont Hospital, Royal Oak, MI (United States); Gallegos, E. [Nuclear Medicine Dept., William Beaumont Hospital, Royal Oak, MI (United States); Fink-Bennett, D. [Nuclear Medicine Dept., William Beaumont Hospital, Royal Oak, MI (United States)

    1995-11-01

    The authors report on an infant suspected of having been abused, who presented with periorbital edema and ecchymoses (clinial `raccoon eyes`). The pattern of the nuclear medicine bone scan suggested neuroblastoma rather than trauma. Both the bone scan and the subsequent MIBG scan revealed multiple abnormalities, including markedly increased activity around the orbits, that we termed the `scintigraphic raccoon eyes` sign. In addition, the grossly abnormal MIBG scan demonstrated avid uptake of MIBG throughout the entire skeleton with essentially complete absence of visualization of the liver and heart (the `MIBG super scan`). These signs have not previously been described in an infant or a child with neuroblastoma. (orig.)

  9. Scintigraphic criteria for administration of therapeutic activities of 131I for ablation of residual thyroid tissue in patients with differentiated thyroid cancer

    International Nuclear Information System (INIS)

    Dzhuzha, D.A.

    2003-01-01

    With the aim to determinate the optical scintigraphic criteria of radioablation of the small parts of residual thyroid tissue (RTT) after a thyroidectomy the results of postoperative monitoring of 29 women aged 23-60 with differentiated thyroid cancer, who did not get the radioiodine therapy, were analyzed. At the single postoperative scintigraphy with 131 I the optimal scintigraphic criteria for radioablation are the relative level of 131 I accumulation in RTT and the relative specific volume activity in RTT. At the values of these indices below 0.21% and 0.16%/sm 3 , respectively, only suppressive thyroid hormone therapy and standard monitoring are recommended

  10. Updated Vertical Extent of Collision Damage

    DEFF Research Database (Denmark)

    Tagg, R.; Bartzis, P.; Papanikolaou, P.

    2002-01-01

    The probabilistic distribution of the vertical extent of collision damage is an important and somewhat controversial component of the proposed IMO harmonized damage stability regulations for cargo and passenger ships. The only pre-existing vertical distribution, currently used in the international...

  11. The Geographic Extent of Global Supply Chains

    DEFF Research Database (Denmark)

    Machikita, Tomohiro; Ueki, Yasushi

    2012-01-01

    We study the extent to which inter-firm relationships are locally concentrated and what determines firm differences in geographic proximity to domestic or foreign suppliers and customers. From micro-data on selfreported customer and supplier data of firms in Indonesia, the Philippines, Thailand, ...

  12. Scintigraphic calf perfusion symmetry after exercise and prediction of cardiovascular events: One stone to kill two birds?

    International Nuclear Information System (INIS)

    Tellier, Philippe; Lecouffe, Pascal; Zureik, Mahmoud

    2007-01-01

    Background: Peripheral arterial disease (PAD) is commonly associated with a high cardiovascular mortality and morbidity as a marker of plurifocal atherosclerosis. Whether exercise thallium perfusion muscular asymmetry in the legs associated with PAD has prognostic value is unknown. Such a hypothesis was evaluated in a prospective study which remains the gold standard in clinical research. Methods and results: Scintigraphic calf perfusion symmetry after exercise (SCPSE) was measured at the end of a maximal or symptom-limited treadmill exercise test in 358 patients with known or suspected coronary artery disease (CAD). During the follow-up period (mean 85.3±32.8 months), 93 cardiovascular events and deaths (incident cases) occurred. Among those incident cases, the percentage of subjects with higher SCPSE values (third tertile) was 45.2%, versus 29.1% in controls (lower tertiles) (p=0.005). In stepwise multivariate analysis performed with the Cox proportional hazards model, previous CAD and SCPSE were the only significant independent predictors of prognosis. The multivariate relative risk of cardiovascular death or event in subjects with higher values of SCPSE was 1.94 (95% CI: 1.15-3.21; p<0.01). Conclusions: Scintigraphic calf perfusion asymmetry after exercise was independently associated with incident cardiovascular events in high-risk subjects. This index, which is easily and quickly calculated, could be used for evaluation of cardiovascular risk

  13. Scintigraphic calf perfusion symmetry after exercise and prediction of cardiovascular events: One stone to kill two birds?

    Science.gov (United States)

    Tellier, Philippe; Lecouffe, Pascal; Zureik, Mahmoud

    2007-02-01

    BackgroundPeripheral arterial disease (PAD) is commonly associated with a high cardiovascular mortality and morbidity as a marker of plurifocal atherosclerosis. Whether exercise thallium perfusion muscular asymmetry in the legs associated with PAD has prognostic value is unknown. Such a hypothesis was evaluated in a prospective study which remains the gold standard in clinical research. Methods and resultsScintigraphic calf perfusion symmetry after exercise (SCPSE) was measured at the end of a maximal or symptom-limited treadmill exercise test in 358 patients with known or suspected coronary artery disease (CAD). During the follow-up period (mean 85.3±32.8 months), 93 cardiovascular events and deaths (incident cases) occurred. Among those incident cases, the percentage of subjects with higher SCPSE values (third tertile) was 45.2%, versus 29.1% in controls (lower tertiles) ( p=0.005). In stepwise multivariate analysis performed with the Cox proportional hazards model, previous CAD and SCPSE were the only significant independent predictors of prognosis. The multivariate relative risk of cardiovascular death or event in subjects with higher values of SCPSE was 1.94 (95% CI: 1.15-3.21; p<0.01). ConclusionsScintigraphic calf perfusion asymmetry after exercise was independently associated with incident cardiovascular events in high-risk subjects. This index, which is easily and quickly calculated, could be used for evaluation of cardiovascular risk.

  14. In vivo comparative study of hydroxyapatite labeled with different radioisotopes: evaluation of the scintigraphic images

    Energy Technology Data Exchange (ETDEWEB)

    Couto, Renata Martinussi; Barboza, Marycel Figols de; Souza, Adriano Aparecido de; Muramoto, Emiko; Mengatti, Jair; Araujo, Elaine Bortoleti de, E-mail: rmcouto@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Radiofarmacia

    2008-07-01

    Rheumatoid arthritis (RA) is a chronic inflammatory disorder of joints that is characterized by the inflammation and proliferation of synovial tissues. Approximately 3% of the adult population in the world is affected by this disease which causes pain, joint immobility and disability. Adyo synovectomy (RSV) is a radiotherapeutic modality where a b--emitting radionuclide is administered locally by intra-articular injection on the form of a colloid or radiolabeled particulate. RSV is a well-accepted therapeutic procedure in inflammatory joint diseases and has been successfully employed for more than 50 years as a viable alternative to surgical and chemical synovectomy in the treatment of RA and other inflammatory arthropathies. There are several radionuclides available for this purpose such as {sup 177}Lu, {sup 90}Y, {sup 153}Sm, {sup 165}Dy, and {sup 166}Ho. Hydroxyapatite (HA) is one of the preferred particulates for this application because it is the major chemical constituent of skeletal bone and it is converted into Ca and PO4 ions in the body. In addition HA is completely eliminated over a period of six weeks. The aim of this work is to compare the in vivo stability of hydroxyapatite labeled with {sup 177}Lu, {sup 90}Y and {sup 153}Sm in order to determine the influence of the radionuclide on biological pattern. In biological studies, 100mL of labeled HAs suspended in normal saline were injected into normal knee joints of Wistar rats and the retention of the activity into the synovium was determined. Labeled particles were also injected by intravenous and intramuscular administration, to verify the biodistribution in the case of an eventual leakage of the products from the joint. Sequential scintigraphic images were acquired from 1 hour to 7 days p.i. after anesthetizing the animals with ketamine. Hydroxyapatite was radiolabeled by all radionuclides with high yield. {sup 177}Lu-HA, {sup 90}Y-HA and {sup 153}Sm-HA were retained in the joint for 7 days, showing

  15. In vivo comparative study of hydroxyapatite labeled with different radioisotopes: evaluation of the scintigraphic images

    International Nuclear Information System (INIS)

    Couto, Renata Martinussi; Barboza, Marycel Figols de; Souza, Adriano Aparecido de; Muramoto, Emiko; Mengatti, Jair; Araujo, Elaine Bortoleti de

    2008-01-01

    Rheumatoid arthritis (RA) is a chronic inflammatory disorder of joints that is characterized by the inflammation and proliferation of synovial tissues. Approximately 3% of the adult population in the world is affected by this disease which causes pain, joint immobility and disability. Adyo synovectomy (RSV) is a radiotherapeutic modality where a b--emitting radionuclide is administered locally by intra-articular injection on the form of a colloid or radiolabeled particulate. RSV is a well-accepted therapeutic procedure in inflammatory joint diseases and has been successfully employed for more than 50 years as a viable alternative to surgical and chemical synovectomy in the treatment of RA and other inflammatory arthropathies. There are several radionuclides available for this purpose such as 177 Lu, 90 Y, 153 Sm, 165 Dy, and 166 Ho. Hydroxyapatite (HA) is one of the preferred particulates for this application because it is the major chemical constituent of skeletal bone and it is converted into Ca and PO4 ions in the body. In addition HA is completely eliminated over a period of six weeks. The aim of this work is to compare the in vivo stability of hydroxyapatite labeled with 177 Lu, 90 Y and 153 Sm in order to determine the influence of the radionuclide on biological pattern. In biological studies, 100mL of labeled HAs suspended in normal saline were injected into normal knee joints of Wistar rats and the retention of the activity into the synovium was determined. Labeled particles were also injected by intravenous and intramuscular administration, to verify the biodistribution in the case of an eventual leakage of the products from the joint. Sequential scintigraphic images were acquired from 1 hour to 7 days p.i. after anesthetizing the animals with ketamine. Hydroxyapatite was radiolabeled by all radionuclides with high yield. 177 Lu-HA, 90 Y-HA and 153 Sm-HA were retained in the joint for 7 days, showing stability and usefulness as tools in the RSV treatment

  16. Interpretation of Scintigraphic Changes during Chronic Hepatitis and Cirrhosis of the Liver

    Energy Technology Data Exchange (ETDEWEB)

    Gheorghescu, B.; Jovin, G.; Pavel, D.; Hoanca, O.; Marculescu, Lidia; Suseanu, I.; Sparchez, T. [Centre of Gastroenterology, Bucharest (Romania)

    1969-05-15

    Photoscintigrams in black and white and in colour were made of the liver and the hepatic clearance was determined by colloidal {sup 198}Au (dimensions 25 - 30 {mu}m) in 82 patients suffering from chronic hepatitis or cirrhosis confirmed by clinical, humeral and histological criteria. The most characteristic changes in the liver scintigram, found particularly in the cirrhosis patients, were: atrophy of the right lobe (partial or total), sometimes pseudo tumoral in appearance; pale or in- homogeneous left lobe; presence of two centres of maximum radiocolloid uptake (left lobe and right lobe); and extrahepatic fixation (spleen, bone marrow). The colour recording system provided better information than the monochromatic system in the diagnosis of cirrhosis. Hepatic clearance showed a decrease, especially in cases of cirrhosis characterized by extrahepatic uptake of the radiocolloid. In the opinion of the authors, the height of the radioactivity curve registered in the temporal region is an indication, during the stabilization phase, of extrahepatic fixation of the colloidal gold. Its height (h{sub 2}) is greater in those cases where the scintigram indicated higher uptake in the spleen and bone marrow. The T 1/2 study of {sup 51}Cr-labelled erythrocytes and their sequestration in the spleen was made in 30 patients exhibiting increased extrahepatic uptake of colloidal gold. The sequestration of labelled erythrocytes was observed in patients showing large-scale splenic uptake of the radiocolloid. Some of the patients whose photoscintigrams previously showed atrophy of the lower region of the right lobe of the liver and obvious presence of the spleen received injections of colloidal gold in the spleen. After intrasplenic injection, the authors obtained the same scintigraphic image in cirrhosis patients, with persistence of the colloidal gold in the spleen, whereas the image of the spleen remained normal in normal subjects. This proves the existence of a lamellar

  17. Is Eurasian October snow cover extent increasing?

    International Nuclear Information System (INIS)

    Brown, R D; Derksen, C

    2013-01-01

    A number of recent studies present evidence of an increasing trend in Eurasian snow cover extent (SCE) in the October snow onset period based on analysis of the National Oceanic and Atmospheric Administration (NOAA) historical satellite record. These increases are inconsistent with fall season surface temperature warming trends across the region. Using four independent snow cover data sources (surface observations, two reanalyses, satellite passive microwave retrievals) we show that the increasing SCE is attributable to an internal trend in the NOAA CDR dataset to chart relatively more October snow cover extent over the dataset overlap period (1982–2005). Adjusting the series for this shift results in closer agreement with other independent datasets, stronger correlation with continentally-averaged air temperature anomalies, and a decrease in SCE over 1982–2011 consistent with surface air temperature warming trends over the same period. (letter)

  18. Scintigraphic scoring system for grading severity of gastro-esophageal reflux on 99mTc sulfur colloid gastro-esophageal reflux scintigraphy: a prospective study of 39 cases with pre and post treatment assessment

    International Nuclear Information System (INIS)

    Puranik, Ameya D.; Nair, Gopinathan; Bandyopadhyay, Abhijit; Shinto, Ajit; Zade, Anand; Aggarwal, Rajiv

    2013-01-01

    The study aimed at developing a scoring system for scintigraphic grading of gastro-esophageal reflux (GER), on gastro-esophageal reflux scintigraphy (GERS) and comparison of clinical and scintigraphic scores, pre- and post-treatment. A total of 39 cases with clinically symptomatic GER underwent 99m Tc sulfur colloid GERS; scores were assigned based on the clinical and scintigraphic parameters. Post domperidone GERS was performed after completion of treatment. Follow up GERS was performed and clinical and scintigraphic parameters were compared with baseline parameters. Paired t-test on pre and post domperidone treatment clinical scores showed that the decline in post-treatment scores was highly significant, with P value < 0.001. The scintigraphic scoring system had a sensitivity of 93.9% in assessing treatment response to domperidone, specificity of 83.3% i.e., 83.3% of children with no decline in scintigraphic scores show no clinical response to Domperidone. The scintigraphic scoring system had a positive predictive value of 96.9% and a negative predictive value of 71.4%. GERS with its quantitative parameters is a good investigation for assessing the severity of reflux and also for following children post-treatment. (author)

  19. Causes of appearance of scintigraphic hot areas on thyroid scintigraphy analyzed with clinical features and comparative ultrasonographic findings

    Energy Technology Data Exchange (ETDEWEB)

    Iwata, Masahiro [Hikone Municipal Hospital, Shiga (Japan); Kasagi, Kanji [Takamatsu Red Cross Hospital, Kagawa (Japan); Hatabu, Hiroto [Univ. of Pennsylvania Medical Center, PA (United States); Misaki, Takashi; Iida, Yasuhiro; Fujita, Toru; Konishi, Junji [Kyoto Univ. (Japan). Graduate School of Medicine

    2002-06-01

    This study was done retrospectively to analyze the ultrasonographic (US) findings in thyroid scintigraphic hot areas (HA). Three-thousand, eight-hundred and thirty-nine consecutive patients who underwent {sup 99m}Tc-pertechnetate (n=3435) or {sup 123}I (n=457) scintigraphy were analyzed. HA were regarded as present when the tracer concentration was greater than the remaining thyroid tissue, or when hemilobar uptake was observed. High-resolution US examinations were performed with a real-time electronic linear scanner with a 7.5 or 10 MHz transducer. One hundred and four (2.7%) were found to be scintigraphic HA (n=120). US revealed a nodular lesion or well-demarcated thyroid tissue corresponding to the HA in 94 areas (78.4%, Category 1), an ill-defined region with different echogenicity in 13 areas (10.8%, Category 2), and no correlating lesion in 13 areas (10.8%, Category 3). These 104 patients included 43 with adenomatous goiter (59 areas), 33 with adenoma, 11 with Hashimoto's thyroiditis, 5 with primary thyroid cancer, 4 with euthyroid ophthalmic Graves' disease (EOG), 3 with hemilobar atrophy or hypogenesis, 2 with hemilobar agenesis, 2 with hypothyroidism with blocking-type TSH-receptor antibodies (TSHRAb), 1 with acute suppurative thyroiditis. Among the 59 adenomatous nodules and 33 adenomas, 51 (86.4%) and 32 (97.0%), respectively, belonged to Category 1. A solitary toxic nodule was significantly larger and occurs more often in older patients than in younger patients. On the other hand, all 17 patients with known autoimmune thyroid diseases including Hashimoto's thyroiditis, EOG and hypothyroidism with blocking TSHRAb belonged to Category 2 or 3. Possible underlying mechanisms are hyperfunctioning tumors or nodules, localized functioning thyroid tissue freed from autoimmune destruction, inflammation or tumor invasion, congenital abnormality, clusters of hyperactive follicular cells caused by long-term TSH and/or TSHRAb stimulation, asymmetry

  20. Causes of appearance of scintigraphic hot areas on thyroid scintigraphy analyzed with clinical features and comparative ultrasonographic findings.

    Science.gov (United States)

    Iwata, Masahiro; Kasagi, Kanji; Hatabu, Hiroto; Misaki, Takashi; Iida, Yasuhiro; Fujita, Toru; Konishi, Junji

    2002-06-01

    This study was done retrospectively to analyze the ultrasonographic (US) findings in thyroid scintigraphic hot areas (HA). Three-thousand, eight-hundred and thirty-nine consecutive patients who underwent 99mTc-pertechnetate (n = 3435) or 123I (n = 457) scintigraphy were analyzed. HA were regarded as present when the tracer concentration was greater than the remaining thyroid tissue, or when hemilobar uptake was observed. High-resolution US examinations were performed with a real-time electronic linear scanner with a 7.5 or 10 MHz transducer. One hundred and four (2.7%) were found to be scintigraphic HA (n = 120). US revealed a nodular lesion or well-demarcated thyroid tissue corresponding to the HA in 94 areas (78.4%, Category 1), an ill-defined region with different echogenicity in 13 areas (10.8%, Category 2), and no correlating lesion in 13 areas (10.8%, Category 3). These 104 patients included 43 with adenomatous goiter (59 areas), 33 with adenoma, 11 with Hashimoto's thyroiditis, 5 with primary thyroid cancer, 4 with euthyroid ophthalmic Graves' disease (EOG), 3 with hemilobar atrophy or hypogenesis, 2 with hemilobar agenesis, 2 with hypothyroidism with blocking-type TSH-receptor antibodies (TSHRAb), I with acute suppurative thyroiditis. Among the 59 adenomatous nodules and 33 adenomas, 51 (86.4%) and 32 (97.0%), respectively, belonged to Category 1. A solitary toxic nodule was significantly larger and occurs more often in older patients than in younger patients. On the other hand, all 17 patients with known autoimmune thyroid diseases including Hashimoto's thyroiditis, EOG and hypothyroidism with blocking TSHRAb belonged to Category 2 or 3. Possible underlying mechanisms are 1) hyperfunctioning tumors or nodules, 2) localized functioning thyroid tissue freed from autoimmune destruction, inflammation or tumor invasion, 3) congenital abnormality, 4) clusters of hyperactive follicular cells caused by long-term TSH and/or TSHRAb stimulation, 5) asymmetry, etc

  1. Causes of appearance of scintigraphic hot areas on thyroid scintigraphy analyzed with clinical features and comparative ultrasonographic findings

    International Nuclear Information System (INIS)

    Iwata, Masahiro; Kasagi, Kanji; Hatabu, Hiroto; Misaki, Takashi; Iida, Yasuhiro; Fujita, Toru; Konishi, Junji

    2002-01-01

    This study was done retrospectively to analyze the ultrasonographic (US) findings in thyroid scintigraphic hot areas (HA). Three-thousand, eight-hundred and thirty-nine consecutive patients who underwent 99m Tc-pertechnetate (n=3435) or 123 I (n=457) scintigraphy were analyzed. HA were regarded as present when the tracer concentration was greater than the remaining thyroid tissue, or when hemilobar uptake was observed. High-resolution US examinations were performed with a real-time electronic linear scanner with a 7.5 or 10 MHz transducer. One hundred and four (2.7%) were found to be scintigraphic HA (n=120). US revealed a nodular lesion or well-demarcated thyroid tissue corresponding to the HA in 94 areas (78.4%, Category 1), an ill-defined region with different echogenicity in 13 areas (10.8%, Category 2), and no correlating lesion in 13 areas (10.8%, Category 3). These 104 patients included 43 with adenomatous goiter (59 areas), 33 with adenoma, 11 with Hashimoto's thyroiditis, 5 with primary thyroid cancer, 4 with euthyroid ophthalmic Graves' disease (EOG), 3 with hemilobar atrophy or hypogenesis, 2 with hemilobar agenesis, 2 with hypothyroidism with blocking-type TSH-receptor antibodies (TSHRAb), 1 with acute suppurative thyroiditis. Among the 59 adenomatous nodules and 33 adenomas, 51 (86.4%) and 32 (97.0%), respectively, belonged to Category 1. A solitary toxic nodule was significantly larger and occurs more often in older patients than in younger patients. On the other hand, all 17 patients with known autoimmune thyroid diseases including Hashimoto's thyroiditis, EOG and hypothyroidism with blocking TSHRAb belonged to Category 2 or 3. Possible underlying mechanisms are hyperfunctioning tumors or nodules, localized functioning thyroid tissue freed from autoimmune destruction, inflammation or tumor invasion, congenital abnormality, clusters of hyperactive follicular cells caused by long-term TSH and/or TSHRAb stimulation, asymmetry, etc. Scintigraphic HA are

  2. Research Misconduct—Definitions, Manifestations and Extent

    Directory of Open Access Journals (Sweden)

    Lutz Bornmann

    2013-10-01

    Full Text Available In recent years, the international scientific community has been rocked by a number of serious cases of research misconduct. In one of these, Woo Suk Hwang, a Korean stem cell researcher published two articles on research with ground-breaking results in Science in 2004 and 2005. Both articles were later revealed to be fakes. This paper provides an overview of what research misconduct is generally understood to be, its manifestations and the extent to which they are thought to exist.

  3. To what extent can the nuclear public relations be effective?

    Energy Technology Data Exchange (ETDEWEB)

    Ohnishi, Teruaki [CRC Research Institute, Tokyo (Japan)

    1996-06-01

    The effect of public relations (PRs) on the public`s attitude to nuclear energy was assessed using a model developed under the assumption that the extent of attitude change of the public by the PRs activity is essentially the same as that by the nuclear information released by the newsmedia. The attitude change of the public was quantitatively estimated by setting variables explicitly manifesting the activities such as the circulation of exclusive publicity and the area of advertising messages in the newspaper as parameters. The public`s attitude became clear to have a nonlinear dependence on the amount of activity, the extent of its change being varied considerably with demographic classes. Under a given financial condition, the offer of PRs information to the people, as many as possible in a target region, in spite of its little force of appeal, was found to be more effective for the amelioration of public attitude than the repeated offer of the information to a limited member of the public. It also became clear that there exists the most effective media mix for the activity depending on the extent of target region and on the target class of demography, therefore, it is quite significant to determine beforehand the proper conditions for the activity to be executed, such a situation indicating the need for the introduction of nuclear PRs management. (Author).

  4. To what extent can the nuclear public relations be effective?

    International Nuclear Information System (INIS)

    Ohnishi, Teruaki

    1996-01-01

    The effect of public relations (PRs) on the public's attitude to nuclear energy was assessed using a model developed under the assumption that the extent of attitude change of the public by the PRs activity is essentially the same as that by the nuclear information released by the newsmedia. The attitude change of the public was quantitatively estimated by setting variables explicitly manifesting the activities such as the circulation of exclusive publicity and the area of advertising messages in the newspaper as parameters. The public's attitude became clear to have a nonlinear dependence on the amount of activity, the extent of its change being varied considerably with demographic classes. Under a given financial condition, the offer of PRs information to the people, as many as possible in a target region, in spite of its little force of appeal, was found to be more effective for the amelioration of public attitude than the repeated offer of the information to a limited member of the public. It also became clear that there exists the most effective media mix for the activity depending on the extent of target region and on the target class of demography, therefore, it is quite significant to determine beforehand the proper conditions for the activity to be executed, such a situation indicating the need for the introduction of nuclear PRs management. (Author)

  5. Scintigraphic myocardial imaging with sup(99m)Tc-labelled pyrophosphate of experimentally produced cardiomyopathy in dogs

    Energy Technology Data Exchange (ETDEWEB)

    Duska, F.; Novak, J.; Vizda, J.; Kubicek, J.; Kafka, P.; Mazurova, Y.; Bradna, P.

    1981-12-01

    Scintigraphic examination of the myocardium using sup(99m)Tc-labelled pyrophosphate was carried out in 10 dogs with experimentally produced cardiomyopathy. This was brought by introvenous administration of high doses of adrenalin and theophylline. The scan was positive in 8 out of 10 dogs. Hot foci were very extensive. The degree of accumulation was however low (2+). Histological examination of the myocardium using the light microscope showed only scarcely distinguishable damage to the tissue without the presence of necrosis. ECG examinations were normal in all cases. By means of sup(99m)Tc-labelled pyrophosphate even very small myocardial disorders can thus be detected. This fact may be of clinical importance for an early diagnosis of heart lesions.

  6. NEPHRUS: model of intelligent multilayers expert system for evaluation of the renal system based on scintigraphic images analysis

    International Nuclear Information System (INIS)

    Silva, Jose W.E. da; Schirru, Roberto; Boasquevisque, Edson M.

    1997-01-01

    This work develops a prototype for the system model based on Artificial Intelligence devices able to perform functions related to scintigraphic image analysis of the urinary system. Criteria used by medical experts for analysis images obtained with 99m Tc+DTPA and/or 99m Tc+DMSA were modeled and a multi resolution diagnosis technique was implemented. Special attention was given to the programs user interface design. Human Factor Engineering techniques were considered so as to ally friendliness and robustness. Results obtained using Artificial Neural Networks for the qualitative image analysis and the knowledge model constructed shows the feasibility of Artificial Intelligence implementation that use 'inherent' abilities of each technique in the resolution of diagnosis image analysis problems. (author). 12 refs., 2 figs., 2 tabs

  7. Synthesis and preliminary scintigraphic evaluation of in vivo distribution of 11C-hydroxyurea/isohydroxyurea and 11C-cyanate

    International Nuclear Information System (INIS)

    Winstead, M.B.; Chern, C.-I.; Lin, T.-H.; Khentigan, A.; Lamb, J.F.; Winchell, H.S.

    1978-01-01

    H 11 CN, produced directly from proton bombardment of 99% N 2 -1% H 2 [ 14 N(p, α) 11 C], was oxidized by KMn0 4 to 11 C-cyanate which was added to hydroxylamine at -5 to 0 0 C to yield a mixture of hydroxyurea and isohydroxyurea. Scintigraphic evaluation of in vivo distribution in a dog following administration of K0 11 CN showed diffuse whole-body distribution, apparently including brain, with greater activity seen in regions of the heart, liver, and kidneys. Similar evaluation of a dog given 11 C-hydroxyurea/isohydroxyurea showed early localization of activity in the region of the heart which appeared to be due to activity in the myocardium. However, tissue activity measured in rats after administration of this material failed to demonstrate concentration in the myocardium. (author)

  8. Clinical, radiographic and scintigraphic aspects of the trapeziometacarpal osteoarthritis; Caracterizacao clinica, radiografica e cintilografica da osteoartrose trapeziometacarpiana

    Energy Technology Data Exchange (ETDEWEB)

    Kaziyama, Helena Hideko Seguchi

    1996-12-31

    Trapeziometacarpal osteoarthritis occurs mainly in women during the menopausal period. It is related to manual activities and is usually bilateral. The onset is insidious and the evolution is slow and progressive. It is characterized by of strength and pain in the basis of the thumb resulting in limitation of the use and function of the hand. The diagnosis of this condition is based on the physical examination. The manouver of compression axial-rotation of the trapezimetacarpal joint is a common positive finding. Typical findings of osteoarthritis are present in the radiological studies. Scintigraphic images have a predictive value. The early diagnosis is important to avoid the risk factors and to prevent disabilities of the hand. (author) 102 refs., 18 figs., 10 tabs.

  9. Clinical, radiographic and scintigraphic aspects of the trapeziometacarpal osteoarthritis; Caracterizacao clinica, radiografica e cintilografica da osteoartrose trapeziometacarpiana

    Energy Technology Data Exchange (ETDEWEB)

    Kaziyama, Helena Hideko Seguchi

    1997-12-31

    Trapeziometacarpal osteoarthritis occurs mainly in women during the menopausal period. It is related to manual activities and is usually bilateral. The onset is insidious and the evolution is slow and progressive. It is characterized by of strength and pain in the basis of the thumb resulting in limitation of the use and function of the hand. The diagnosis of this condition is based on the physical examination. The manouver of compression axial-rotation of the trapezimetacarpal joint is a common positive finding. Typical findings of osteoarthritis are present in the radiological studies. Scintigraphic images have a predictive value. The early diagnosis is important to avoid the risk factors and to prevent disabilities of the hand. (author) 102 refs., 18 figs., 10 tabs.

  10. Scintigraphic detection of metastatic melanoma using indium 111/DTPA conjugated anti-gp240 antibody (ZME-018)

    International Nuclear Information System (INIS)

    Kirkwood, J.M.; Neumann, R.D.; Zoghbi, S.S.; Ernstoff, M.S.; Cornelius, E.A.; Shaw, C.; Ziyadeh, T.; Fine, J.A.; Unger, M.W.

    1987-01-01

    We evaluated the toxicity, pharmacokinetics, and localization of a monoclonal IgG2 alpha murine anti-human melanoma (gp240) antibody (ZME-018) that recognizes a tumor-associated cell surface glycoprotein of 240,000 molecular weight present in most melanomas. The antibody was conjugated with DTPA (diethylenetriamine pentaacetic acid) and labeled by chelation of 111 In. One mg of antibody labeled with 5 mCi of 111 In was infused, together with 0 to 40 mg of cold carrier ZME-018. The blood clearance, urinary excretion, and in vivo localization were determined in 26 patients. Scintigraphic images were obtained at 24 hours and 72 hours in all patients. Mild toxicity occurred in one patient. The half-time clearance of labeled monoclonal murine antibody (MoAb) from the blood increased from 16.1 hours at an antibody dose of 1 mg to 35.9 hours at 40 mg. Males showed faster clearance from the blood than did females or a single castrated male, perhaps due to selective concentration of antibody in the testes. Nonspecific uptake in liver, spleen, bone marrow, and intestine was seen in all patients. The percentage of known metastatic foci detected increased with the total dosage of antibody, from 23% at doses less than or equal to 5 mg, to 65%, 87% and 78% for 10, 20, and 40 mg, respectively. We conclude that at doses of greater than or equal to 10 mg, ZME-018 is a safe and potentially useful agent for the scintigraphic detection of metastatic malignant melanoma

  11. Increased technetium uptake is not equivalent to muscle necrosis: scintigraphic, morphological and intramuscular pressure analyses of sore muscles after exercise

    Science.gov (United States)

    Crenshaw, A. G.; Friden, J.; Hargens, A. R.; Lang, G. H.; Thornell, L. E.

    1993-01-01

    A scintigraphic technique employing technetium pyrophosphate uptake was used to identify the area of skeletal muscle damage in the lower leg of four runners 24 h after an ultramarathon footrace (160 km). Most of the race had been run downhill which incorporated an extensive amount of eccentric work. Soreness was diffuse throughout the posterior region of the lower leg. In order to interpret what increased technetium uptake reflects and to express extreme endurance related damages, a biopsy was taken from the 3-D position of abnormal uptake. In addition, intramuscular pressures were determined in the deep posterior compartment. Scintigraphs revealed increased technetium pyrophosphate uptake in the medial portion of the gastrocnemius muscle. For 3698 fibres analysed, 33 fibres (1%) were necrotic, while a few other fibres were either atrophic or irregular shaped. A cluster of necrotic fibres occurred at the fascicular periphery for one subject and fibre type grouping occurred for another. Ultrastructural analysis revealed Z-line streaming near many capillaries and variously altered subsarcolemmal mitochondria including some with paracrystalline inclusions. The majority of the capillaries included thickened and irregular shaped endothelial cells. Intramuscular pressures of the deep posterior compartment were slightly elevated (12-15 mmHg) for three of the four subjects. Increased technetium uptake following extreme endurance running does not just reflect muscle necrosis but also subtle fibre abnormalities. Collectively, these pathological findings are attributed to relative ischaemia occurring during the race and during pre-race training, whereas, intramuscular pressure elevations associated with muscle soreness are attributed to mechanical stress caused by extensive eccentric work during the race.

  12. Scintigraphic scoring system for grading severity of gastro-esophageal reflux on 99mTc sulfur colloid gastro-esophageal reflux scintigraphy: A prospective study of 39 cases with pre and post treatment assessment.

    Science.gov (United States)

    Puranik, Ameya D; Nair, Gopinathan; Aggarwal, Rajiv; Bandyopadhyay, Abhijit; Shinto, Ajit; Zade, Anand

    2013-04-01

    The study aimed at developing a scoring system for scintigraphic grading of gastro-esophageal reflux (GER), on gastro-esophageal reflux scintigraphy (GERS) and comparison of clinical and scintigraphic scores, pre- and post-treatment. A total of 39 cases with clinically symptomatic GER underwent 99mTc sulfur colloid GERS; scores were assigned based on the clinical and scintigraphic parameters. Post domperidone GERS was performed after completion of treatment. Follow up GERS was performed and clinical and scintigraphic parameters were compared with baseline parameters. Paired t-test on pre and post domperidone treatment clinical scores showed that the decline in post-treatment scores was highly significant, with P value reflux and also for following children post-treatment.

  13. Scintigraphic imaging of focal hypoxic tissue: development and clinical applications of 123I-IAZA

    Directory of Open Access Journals (Sweden)

    Leonard I. Wiebe

    2002-09-01

    Full Text Available Affected tissues in a number of diseases, including cancer, stroke, cardiac infarction and diabetes, develop focal tissue hypoxia during their progression. The presence of hypoxic tissue may make the disease refractory to therapy, as in the case of solid tumor therapy using low LET ionizing radiation. In other pathologies, the detection of viable but hypoxic tissues may serve as a prodromal indicator of developing disease (e.g. diabetes,or as a prognostic indicator for management of the disease (e.g. stroke. Over the past two decades, a number of hypoxia radioimaging agents have been developed and tested clinically. Of these, 18F-Fmiso and 123I-IAZA are the most widely used radiotracers for PET and SPECT/planar imaging, respectively. IAZA and Fmiso are a 2-nitroimidazoles that chemically bind to subcellular components of viable hypoxic tissues. They sensitize hypoxic tumour to the killing effects of ionizing radiation via mechanisms that mimic the radiosensitizing effects of oxygen, and are therefore called oxygen mimetics. The oxygen mimetic effect is attributable in large part to the covalent binding of reductively-activated nitroimidazole intermediates to critical cellular macromolecules. Nitroimidazoles labelled with gamma-emitting radionuclides (e.g. 18F-Fmiso and 123I-IAZA have been used as scintigraphic markers of tumour hypoxia, based on the need to identify radioresistant hypoxic tumour cells as part of the radiotherapy planning process. Broader interest in non-invasive, imaging-based identification of focal hypoxia in a number of diseases has extended hypoxia studies to include peripheral vascular disease associated with diabetes, rheumatoid arthritis, stroke, myocardial ischaemia, brain trauma and oxidative stress. In this review, the current status of hypoxia-selective studies with 123I-IAZA , an experimental diagnostic radiopharmaceutical, is reviewed with respect to its pre-clinical development and clinical applications.Os tecidos

  14. Value of scintigraphic examinations in bone marrow disease. Report of 2 cases

    Energy Technology Data Exchange (ETDEWEB)

    Yokomizo, Yu; Nakayama, Chikashi; Kimoto, Tatsuya; Nakayama, Taku; Matsuura, Takashi [Univ. of Occupational and Environmental Health Kitakyushu, Fukuoka (Japan). School of Medicine

    1983-08-01

    We reported 2 cases in which bone scintigraphy and /sup 67/Ga scintigraphy with or without bone-marrow scintigraphy were useful in determining the nature and extent of bone marrow abnormalities. Case 1 was a 1 1/12-year-old male infant with acute lymphoblastic leukemia and case 2 was a 58-year-old man with the final diagnosis of leukemic transformation of myelofibrosis.

  15. Complex examination of osteochondrosis deformans coxae juvenilis (Calve-Legg-Perthes). 3. Scintigraphic and arteriographic examination

    Energy Technology Data Exchange (ETDEWEB)

    Siegling, C.W.; Ritter, H.; Endert, G.

    1985-12-01

    By means of 120 scintigrams and 42 arteriographs it was shown that blood vessel tamponade caused the development of femoral head necrosis. Native radiography, scintiscanning and arteriography rendered possible an early diagnosis of the disease. The temporal course of the disease could be controlled. The site of the necrosis and thus the prognosis of the disease are dependent on extent and localization of the disturbed blood supply.

  16. Gallium-68 DOTA-TATE Positron Emission Tomography/Computed Tomography: Scintigraphic Changes of Adrenal Glands Following Management of Ectopic Cushing's Syndrome by Steroidogenesis Inhibitors

    International Nuclear Information System (INIS)

    Huang, Yu-Ting; Aziz, Shaikh Irfan; Kumar, Aravind S. Ravi

    2014-01-01

    In the era of emerging functional imaging techniques, an understanding of the effects of hormonal therapies on the scintigraphic appearance of endocrine organs is desirable to minimize the erroneous scan interpretation. The mechanisms by which changes in the scintigraphic appearance of endocrine organs occur however sometimes remain ambiguous. This case demonstrates the gallium-68 (Ga-68) DOTA-TATE positron emission tomography/computed tomography (CT) appearance of adrenal glands following management with steroidogenesis inhibitors. The potential mechanisms underlying this change are discussed. A 17-year-old boy with adrenocorticotropic hormone (ACTH) dependent Cushing's syndrome secondary to ectopic ACTH secretion underwent pre- and post-metyrapone and dexamethasone treatment Ga-68 DOTA-TATE scans 4 months apart. Pretreatment, both adrenals demonstrated normal symmetrical prominent Ga-68 DOTA-TATE uptake and normal CT appearance. The posttherapy scan revealed marked symmetrical suppression of Ga-68 DOTA-TATE uptake, but with bilateral adrenal hypertrophy on CT

  17. Integrating remotely sensed surface water extent into continental scale hydrology.

    Science.gov (United States)

    Revilla-Romero, Beatriz; Wanders, Niko; Burek, Peter; Salamon, Peter; de Roo, Ad

    2016-12-01

    In hydrological forecasting, data assimilation techniques are employed to improve estimates of initial conditions to update incorrect model states with observational data. However, the limited availability of continuous and up-to-date ground streamflow data is one of the main constraints for large-scale flood forecasting models. This is the first study that assess the impact of assimilating daily remotely sensed surface water extent at a 0.1° × 0.1° spatial resolution derived from the Global Flood Detection System (GFDS) into a global rainfall-runoff including large ungauged areas at the continental spatial scale in Africa and South America. Surface water extent is observed using a range of passive microwave remote sensors. The methodology uses the brightness temperature as water bodies have a lower emissivity. In a time series, the satellite signal is expected to vary with changes in water surface, and anomalies can be correlated with flood events. The Ensemble Kalman Filter (EnKF) is a Monte-Carlo implementation of data assimilation and used here by applying random sampling perturbations to the precipitation inputs to account for uncertainty obtaining ensemble streamflow simulations from the LISFLOOD model. Results of the updated streamflow simulation are compared to baseline simulations, without assimilation of the satellite-derived surface water extent. Validation is done in over 100 in situ river gauges using daily streamflow observations in the African and South American continent over a one year period. Some of the more commonly used metrics in hydrology were calculated: KGE', NSE, PBIAS%, R 2 , RMSE, and VE. Results show that, for example, NSE score improved on 61 out of 101 stations obtaining significant improvements in both the timing and volume of the flow peaks. Whereas the validation at gauges located in lowland jungle obtained poorest performance mainly due to the closed forest influence on the satellite signal retrieval. The conclusion is that

  18. Evaluation of patients with coronary artery disease during exercise: the relation between extent of disease and perfusion deficit

    International Nuclear Information System (INIS)

    Hakki, A.H.; DePace, N.; Iskandrian, A.S.

    1984-01-01

    The purpose of this study was to assess the relation between the extent of coronary artery disease (CAD) and size of exercise-induced myocardial hypoperfusion in 79 patients with angiographically documented CAD. None of the patients had Q-wave myocardial infarction. Fifty patients had one-vessel disease, ten had two-vessel disease, and 19 patients had three-vessel or left main disease. From a scintigraphic functional standpoint, patients were classified into two groups: 28 patients (35%) had large perfusion defects and 51 patients (65%) had small defects. The size of the thallium-201 perfusion defect during exercise was assessed as the perimeter of the defect in each projection expressed as a percentage abnormality of the total left ventricular perimeter in that projection. The average abnormality from the three projections was used in the final analysis. Eleven patients with large defects (39%) had one-vessel disease and 12 patients with small defects (24%) had multivessel disease. Stepwise multivariate discriminate analysis identified the number of diseased vessels (F . 13.9), the change in systolic blood pressure from rest to exercise (F . 10.8), the exercise heart rate (F . 9.1), and exercise electrocardiographic response (F . 7.8) as significant associates of the size of the perfusion defect (predictive accuracy . 70%). We conclude that the size of hypoperfused myocardium during exercise is variable in patients with CAD. Discriminate analysis identified the extent of CAD, exercise heart rate, change in systolic pressure from rest to exercise, and exercise electrocardiographic response as significant associates of the size of the defect

  19. Scintigraphic demonstration of a iatrogenic rhabdomyolysis im McArdle's syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Neumann, P.; Rumpf, K.W.; Kaiser, H.; Meinck, H.M.; Goebel, H.H.; Schicha, H.; Emrich, D.

    1982-02-01

    In a patient with late onset McArdle's disease local rhabdomyolysis and massive myoglobinuria were provoked by a routine diagnostic procedure - the forearm ischemic work test. Localisation and extent of rhabdomyolysis could be demonstrated by a conventional whole-body scanning technique using sup(99m)Tc methylenediphosphonate as a tracer. It is concluded that the forearm ischemic work test is not without risk in patients with McArdle's disease, and care should be taken to prevent myoglobinuric renal failure in these patients.

  20. Scintigraphic demonstration of a iatrogenic rhabdomyolysis im McArdle's syndrome

    International Nuclear Information System (INIS)

    Neumann, P.; Rumpf, K.W.; Kaiser, H.; Meinck, H.M.; Goebel, H.H.; Schicha, H.; Emrich, D.; Goettingen Univ.; Goettingen Univ.; Goettingen Univ.; Goettingen Univ.

    1982-01-01

    In a patient with late onset McArdle's disease local rhabdomyolysis and massive myoglobinuria were provoked by a routine diagnostic procedure - the forearm ischemic work test. Localisation and extent of rhabdomyolysis could be demonstrated by a conventional whole-body scanning technique using sup(99m)Tc methylenediphosphonate as a tracer. It is concluded that the forearm ischemic work test is not without risk in patients with McArdle's disease, and care should be taken to prevent myoglobinuric renal failure in these patients. (orig.) [de

  1. Idiopathic pulmonary fibrosis. A rare cause of scintigraphic ventilation-perfusion mismatch

    International Nuclear Information System (INIS)

    Pochis, W.T.; Krasnow, A.Z.; Collier, B.D.; Mewissen, M.W.; Almagro, U.A.; Hellman, R.S.; Isitman, A.T.

    1990-01-01

    A case of idiopathic pulmonary fibrosis with multiple areas of mismatch on ventilation-perfusion lung imaging in the absence of pulmonary embolism is presented. Idiopathic pulmonary fibrosis is one of the few nonembolic diseases producing a pulmonary ventilation-perfusion mismatch. In this condition, chest radiographs may not detect the full extent of disease, and xenon-133 ventilation imaging may be relatively insensitive to morbid changes in small airways. Thus, when examining patients with idiopathic pulmonary fibrosis, one should be aware that abnormal perfusion imaging patterns without matching ventilation abnormalities are not always due to embolism. In this setting, contrast pulmonary angiography is often needed for accurate differential diagnosis

  2. Idiopathic pulmonary fibrosis. A rare cause of scintigraphic ventilation-perfusion mismatch

    Energy Technology Data Exchange (ETDEWEB)

    Pochis, W.T.; Krasnow, A.Z.; Collier, B.D.; Mewissen, M.W.; Almagro, U.A.; Hellman, R.S.; Isitman, A.T. (Medical College of Wisconsin, Milwaukee (USA))

    1990-05-01

    A case of idiopathic pulmonary fibrosis with multiple areas of mismatch on ventilation-perfusion lung imaging in the absence of pulmonary embolism is presented. Idiopathic pulmonary fibrosis is one of the few nonembolic diseases producing a pulmonary ventilation-perfusion mismatch. In this condition, chest radiographs may not detect the full extent of disease, and xenon-133 ventilation imaging may be relatively insensitive to morbid changes in small airways. Thus, when examining patients with idiopathic pulmonary fibrosis, one should be aware that abnormal perfusion imaging patterns without matching ventilation abnormalities are not always due to embolism. In this setting, contrast pulmonary angiography is often needed for accurate differential diagnosis.

  3. The extent and importance of intragenic recombination

    Directory of Open Access Journals (Sweden)

    de Silva Eric

    2004-11-01

    Full Text Available Abstract We have studied the recombination rate behaviour of a set of 140 genes which were investigated for their potential importance in inflammatory disease. Each gene was extensively sequenced in 24 individuals of African descent and 23 individuals of European descent, and the recombination process was studied separately in the two population samples. The results obtained from the two populations were highly correlated, suggesting that demographic bias does not affect our population genetic estimation procedure. We found evidence that levels of recombination correlate with levels of nucleotide diversity. High marker density allowed us to study recombination rate variation on a very fine spatial scale. We found that about 40 per cent of genes showed evidence of uniform recombination, while approximately 12 per cent of genes carried distinct signatures of recombination hotspots. On studying the locations of these hotspots, we found that they are not always confined to introns but can also stretch across exons. An investigation of the protein products of these genes suggested that recombination hotspots can sometimes separate exons belonging to different protein domains; however, this occurs much less frequently than might be expected based on evolutionary studies into the origins of recombination. This suggests that evolutionary analysis of the recombination process is greatly aided by considering nucleotide sequences and protein products jointly.

  4. To what extent does immigration affect inequality?

    Science.gov (United States)

    Berman, Yonatan; Aste, Tomaso

    2016-11-01

    The current surge in income and wealth inequality in most western countries, along with the continuous immigration to those countries demand a quantitative analysis of the effect immigration has on economic inequality. This paper presents a quantitative analysis framework providing a way to calculate this effect. It shows that in most cases, the effect of immigration on wealth and income inequality is limited, mainly due to the relative small scale of immigration waves. For a large scale flow of immigrants, such as the immigration to the US, the UK and Australia in the past few decades, we estimate that 10 % ÷ 15 % of the wealth and income inequality increase can be attributed to immigration. The results demonstrate that immigration could possibly decrease inequality substantially, if the characteristics of the immigrants resemble the characteristics of the destination middle class population in terms of wealth or income. We empirically found that the simple linear relation ΔS = 0.18 ρ roughly describes the increase in the wealth share of the top 10 % due to immigration of a fraction ρ of the population.

  5. Liquor circulation disturbance after subarachnoid haemorrhages - comparative pneumoencephalography and liquor scintigraphic investigations

    International Nuclear Information System (INIS)

    Menzel, J.; Georgi, P.; Krastel, A.; Deutsches Krebsforschungszentrum, Heidelberg

    1976-01-01

    Haemorrhages into the subarachnoid space often lead to instant blocking of the liquor circulation pathways with an acute increase of the intracranial pressure and acute venticular enlargement. These liquor circulation disturbances may be diagnosed by liquor scintiscanning as well as by pneumoencephalography. 165 patients were examined by both methods. The following results were obtained: liquor circulation disturbances after subarachnoid bleeding are frequent, they should be expected in 33% of all cases after spontaneous subarachnoid haemorrhages and in 68% of the cases after traumatic subarachnoid haemorrhages. The most severe form of liquor circulation distrubance may also be diagnosed by liquor scintiscanning as well as by pneumoencephalography. Liquor scintiscanning is the more exact method in cases with transitory ventricular reflux, while lumbar pneumoencephalography, in this series, is the method of choice when it comes to documenting the extent of the hydrocephalus. (GSE) [de

  6. Nationwide standardisation and evaluation of scintigraphic gastric emptying: reference values and comparisons between subgroups in a multicentre trial

    International Nuclear Information System (INIS)

    Grybaeck, P.; Hermansson, G.; Lyrenaes, E.; Beckman, K.-W.; Jacobsson, H.; Hellstroem, P.M.

    2000-01-01

    By means of a standardised procedure, reference values for scintigraphic gastric emptying were established. The influence of gender, age, menstrual cycle, body mass index (BMI) and smoking habits was also evaluated. Eight centres recruited 20 healthy subjects each. The meal consisted of a technetium-99m labelled omelet (1300 kJ) and of 150 ml unlabelled soft drink. Geometric means of frontal and dorsal acquisitions were utilised in a linear fit model for determination of the linear emptying rate, and by using the intercepts of the regression line with the 90% and 50% levels, the lag phase and half-emptying time, respectively, were defined. All individuals showed an initial lag phase and subsequent linear emptying. Because of a longer lag phase and a slower linear emptying rate, premenopausal women had a slower gastric emptying than postmenopausal women and men of all ages. The gastric emptying rate increased with age in the women, mainly due to a shortened lag phase, while the emptying rate remained almost unchanged with age in the males. There were no significant differences in results between the centres. The menstrual cycle, BMI and smoking habits did not affect emptying. In conclusion, the fact that the results showed a slower gastric emptying rate in younger women compared with older women and men indicates that it is necessary to use separate reference values for fertile females. (orig.)

  7. A “Proteoglycan Targeting Strategy” for the Scintigraphic Imaging and Monitoring of the Swarm Rat Chondrosarcoma Orthotopic Model

    Directory of Open Access Journals (Sweden)

    Caroline Peyrode

    2011-01-01

    Full Text Available Our lab developed 99mTc-NTP 15-5 radiotracer as targeting proteoglycans (PGs for the scintigraphic imaging of joint. This paper reports preclinical results of 99mTc-NTP 15-5 imaging of an orthotopic model of Swarm rat chondrosarcoma (SRC. 99mTc-NTP 15-5 imaging of SRC-bearing and sham-operated animals was performed and quantified at regular intervals after surgery and compared to bone scintigraphy and tumoural volume. Tumours were characterized by histology and PG assay. SRC exhibited a significant 99mTc-NTP 15-5 uptake at very early stage after implant (with tumour/muscle ratio of 1.61 ± 0.14, whereas no measurable tumour was evidenced. As tumour grew, mean tumour/muscle ratio was increased by 2.4, between the early and late stage of pathology. Bone scintigraphy failed to image chondrosarcoma, even at the later stage of study. 99mTc-NTP 15-5 imaging provided a suitable set of quantitative criteria for the in vivo characterization of chondrosarcoma behaviour in bone environment, useful for achieving a greater understanding of the pathology.

  8. Combined scintigraphic and radiographic diagnosis of bone and joint diseases. Including gamma correction interpretation. 4. rev. and enl. ed.

    Energy Technology Data Exchange (ETDEWEB)

    Bahk, Yong-Whee [Sung Ae General Hospital, Seoul (Korea, Republic of). Dept. of Nuclear Medicine and Radiology

    2013-07-01

    In this fourth edition of Combined Scintigraphic and Radiographic Diagnosis of Bone and Joint Diseases, the text has been thoroughly amended, updated, and partially rearranged to reflect the latest advances. In addition to discussing the role of pinhole imaging in the range of disorders previously covered, the new edition pays detailed attention to the novel diagnostic use of gamma correction pinhole bone scan in a broad spectrum of skeletal disorders, including physical, traumatic, and sports injuries, infectious and non-infectious bone diseases, benign and malignant bone tumors, and soft tissue diseases. A large number of state of the art pinhole scans and corroborative CT, MRI, and/or ultrasound images are presented side by side. The book has been enlarged to encompass various new topics, including occult fractures; cervical sprain and whiplash trauma; bone marrow edema; microfractures of trabeculae; evident, gaping, and stress fractures; and differential diagnosis. This new edition will be essential reading for practitioners and researchers in not only nuclear medicine but also radiology, orthopedic surgery, and pathology.

  9. Combined scintigraphic and radiographic diagnosis of bone and joint diseases. Including gamma correction interpretation. 4. rev. and enl. ed.

    International Nuclear Information System (INIS)

    Bahk, Yong-Whee

    2013-01-01

    In this fourth edition of Combined Scintigraphic and Radiographic Diagnosis of Bone and Joint Diseases, the text has been thoroughly amended, updated, and partially rearranged to reflect the latest advances. In addition to discussing the role of pinhole imaging in the range of disorders previously covered, the new edition pays detailed attention to the novel diagnostic use of gamma correction pinhole bone scan in a broad spectrum of skeletal disorders, including physical, traumatic, and sports injuries, infectious and non-infectious bone diseases, benign and malignant bone tumors, and soft tissue diseases. A large number of state of the art pinhole scans and corroborative CT, MRI, and/or ultrasound images are presented side by side. The book has been enlarged to encompass various new topics, including occult fractures; cervical sprain and whiplash trauma; bone marrow edema; microfractures of trabeculae; evident, gaping, and stress fractures; and differential diagnosis. This new edition will be essential reading for practitioners and researchers in not only nuclear medicine but also radiology, orthopedic surgery, and pathology.

  10. Radiographic and scintigraphic evidence of focal pulmonary neoplasia in three cats with hyperthyroidism: diagnostic and therapeutic considerations

    International Nuclear Information System (INIS)

    Cook, S.M.; Daniel, G.B.; Walker, M.A.; Maddux, J.M.; Jenkins, C.C.; Klebanow, E.R.; Bouley, D.M.; Dean, D.F.; Petersen, M.G.

    1993-01-01

    Three cats were diagnosed as hyperthyroid based on clinical signs, historical findings, laboratory abnormalities, and basal serum thyroxine (T4) concentrations, and/or nuclear thyroid scans. Additionally, a presumptive diagnosis of thyroid carcinoma with pulmonary metastasis was made in each cat based on radiographic or scintigraphic evaluation. All three cats had solitary pulmonary nodules 1.5 to 2 cm in diameter on survey thoracic radiographs; one cat also had chylous pleural effusion and pulmonary lobar consolidation. Focal pulmonary accumulation of sodium pertechnetate (99mTcO4-) and/or radioiodine (131I) corresponding to radiographic lesions were seen in all cats. Two cats were treated with single ablative doses (1111 to 1480 MBq) of 131I; the remaining cat was euthanatized. One of the treated cats died 8 days later; the other cat was euthanatized 22 weeks following treatment. Histopathologic examination of tissue obtained at necropsy confirmed metastatic thyroid carcinoma in one cat and bronchogenic adenocarcinoma in two cats. Our findings indicate that increased radionuclide uptake in focal pulmonary lesions and cytologic evaluation of tissue obtained by fine-needle aspiration are not specific for thyroid tissue

  11. Nationwide standardisation and evaluation of scintigraphic gastric emptying: reference values and comparisons between subgroups in a multicentre trial

    Energy Technology Data Exchange (ETDEWEB)

    Grybaeck, P. [Department of Radiology, Karolinska Hospital, Stockholm (Sweden); Hermansson, G. [Department of Clinical Physiology, Oestra Hospital, Goeteborg (Sweden); Lyrenaes, E. [Department of Medicine, Blekinge Hospital, Karlskrona (Sweden); Beckman, K.-W. [Hospital Physics, Oerebro Hospital (Sweden); Jacobsson, H. [Department of Radiology, Karolinska Hospital, Stockholm (Sweden); Department of Nuclear Medicine, Karolinska Hospital, Stockholm (Sweden); Hellstroem, P.M. [Department of Gastroenterology and Hepatology, Karolinska Hospital, Stockholm (Sweden)

    2000-06-01

    By means of a standardised procedure, reference values for scintigraphic gastric emptying were established. The influence of gender, age, menstrual cycle, body mass index (BMI) and smoking habits was also evaluated. Eight centres recruited 20 healthy subjects each. The meal consisted of a technetium-99m labelled omelet (1300 kJ) and of 150 ml unlabelled soft drink. Geometric means of frontal and dorsal acquisitions were utilised in a linear fit model for determination of the linear emptying rate, and by using the intercepts of the regression line with the 90% and 50% levels, the lag phase and half-emptying time, respectively, were defined. All individuals showed an initial lag phase and subsequent linear emptying. Because of a longer lag phase and a slower linear emptying rate, premenopausal women had a slower gastric emptying than postmenopausal women and men of all ages. The gastric emptying rate increased with age in the women, mainly due to a shortened lag phase, while the emptying rate remained almost unchanged with age in the males. There were no significant differences in results between the centres. The menstrual cycle, BMI and smoking habits did not affect emptying. In conclusion, the fact that the results showed a slower gastric emptying rate in younger women compared with older women and men indicates that it is necessary to use separate reference values for fertile females. (orig.)

  12. Exercise-induced ST-segment depression and myocardial ischemia in patients with hypertrophic cardiomyopathy. Myocardial scintigraphic study

    International Nuclear Information System (INIS)

    Miyai, Nobuyuki; Kawasaki, Tatsuya; Taniguchi, Takuya; Kamitani, Tadaaki; Kawasaki, Shingo; Sugihara, Hiroki

    2005-01-01

    Patients with hypertrophic cardiomyopathy (HCM) sometimes develop myocardial ischemia during exercise in the absence of coronary lesions. The relationship between myocardial ischemia and ST-segment depression was investigated during exercise testing in patients with HCM. Regional hypoperfusion and/or transient left ventricular cavity dilation, a parameter of subendocardial hypoperfusion, were assessed on exercise 99 m Tc-tetrofosmin myocardial scintigraphy in 42 patients with non-obstructive HCM. The scintigraphic results were further correlated with the ST-segment responses to exercise. Regional hypoperfusion or transient left ventricular cavity dilation were observed in 19 (45%) or 16 (38%) patients with HCM, respectively. The incidence of ST-segment depression ≥0.1 mV during exercise testing was similar in HCM patients with regional hypoperfusion, with transient left ventricular cavity dilation, and without hypoperfusion (42%, 38%, 38%, p=0.95). Furthermore, exercise-induced ST-segment depression ≥0.1 mV occurred similarly irrespective of symptoms, exercise tolerance, the degree or the site of hypertrophy, or the presence or absence of resting ST-segment depression. ST-segment depression during exercise testing was common in patients with HCM, but seems to be an unreliable marker of myocardial ischemia as assessed by exercise scintigraphy. (author)

  13. Modification of the labelling autologous erythrocytes with Tc-99m to scintigraphic evaluation of deep vein system

    International Nuclear Information System (INIS)

    Quintero, C.M.; Freire, D.Y.

    1993-01-01

    The purpose of this was the modification of labelled autologous red blood cells in vivo/in vitro. Evaluation consisted in different combinations of Tc-99m radiopharmaceuticals as pyrophosphate (PYP) and stannous chloride (SnCl2), anticoagulants as heparin and acid-citrate-dextrose (ACD), and oxidant agents as hydrogen peroxide (H2O2) and sodium hypochlorite (NaClO); factorial block design was carried out to determinate which one brings a better yield of labelling, and more advantages of availability. Results showed that all tested combinations were above 90% labelled; variance analysis indicated significant difference between the two radiopharmaceuticals (P<0.05), being higher percent of labelling with PYP than SnCl2, and PYP-ACD-NaClO the best combination. It was demonstrated that the procedure is safe because hemocultives realized during the labelling process were all negative, evidencing no bacterial contamination. There were significant erythrocyte-shape modifications, too. Due to low costs and good availability of H2O2 as oxidant agent there were no statistic significant differences between the use of H2O2 or NaClO, the modification PYP-ACD-H2O2 will be used as scintigraphic test for deep vein thrombosis

  14. The impact of therapeutic delay time on acute scintigraphic lesion and ultimate scar formation in children with first febrile UTI.

    Science.gov (United States)

    Oh, Mi Mi; Kim, Jin Wook; Park, Min Gu; Kim, Je Jong; Yoo, Kee Hwan; Moon, Du Geon

    2012-03-01

    We assessed the role of therapeutic delay time (TDT) in acute renal cortical scintigraphic lesion (ASL) and ultimate scar formation (USF) in children with first febrile UTI and whether it is affected by the presence of vesico-ureteral reflux (VUR). 230 children, 90 girls and 140 boys with first febrile UTI were included. Radiologic (USG, DMSA, and VCUG), clinical (age, gender, peak fever, therapeutic delay time) and laboratory (CBC with differential count, ANC (absolute neutrophil count), BUN, Creatinine, urine analysis, gram stain, culture, CRP and ESR) variables were analysed. DMSA was performed within 5 days and after six months. VCUG was performed after acute phase of UTI. The differences in TDT according to the presence of ASL, USF and VUR were assessed. And the correlation between ASL or USF with the duration of TDT was assessed. Of 230 patients enrolled, 142 patients had refluxing UTI and 88 patients had non-refluxing UTI. TDT was the risk factor associated with ASL and USF along with presence of VUR. TDT was longer in ASL positive group compared with the ASL negative group. Also USF group showed longer TDT compared with those without USF in both refluxing UTI and non refluxing UTI. The TDT was significantly shorter in USF group with the presence of VUR. Positive linear association was noted between prevalence of ASL and USF and duration of TDT. In conclusion, the impact of UTI on formation of USF may be enhanced by the presence of VUR with shorter duration of TDT.

  15. Multisensor Analyzed Sea Ice Extent - Northern Hemisphere (MASIE-NH)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Multisensor Analyzed Sea Ice Extent Northern Hemisphere (MASIE-NH) products provide measurements of daily sea ice extent and sea ice edge boundary for the...

  16. Obesity and extent of emphysema depicted at CT

    International Nuclear Information System (INIS)

    Gu, S.; Li, R.; Leader, J.K.; Zheng, B.; Bon, J.; Gur, D.; Sciurba, F.; Jin, C.; Pu, J.

    2015-01-01

    Aim: To investigate the underlying relationship between obesity and the extent of emphysema depicted at CT. Methods and materials: A dataset of 477 CT examinations was retrospectively collected from a study of chronic obstructive pulmonary disease (COPD). The low attenuation areas (LAAs; ≤950 HU) of the lungs were identified. The extent of emphysema (denoted as %LAA) was defined as the percentage of LAA divided by the lung volume. The association between log-transformed %LAA and body mass index (BMI) adjusted for age, sex, the forced expiratory volume in one second as percent predicted value (FEV1% predicted), and smoking history (pack years) was assessed using multiple linear regression analysis. Results: After adjusting for age, gender, smoking history, and FEV1% predicted, BMI was negatively associated with severe emphysema in patients with COPD. Specifically, one unit increase in BMI is associated with a 0.93-fold change (95% CI: 0.91–0.96, p < 0.001) in %LAA; the estimated %LAA for males was 1.75 (95% CI: 1.36–2.26, p < 0.001) times that of females; per 10% increase in FEV1% predicated is associated with a 0.72-fold change (95% CI: 0.69–0.76, p < 0.001) in %LAA. Conclusion: Increasing obesity is negatively associated with severity of emphysema independent of gender, age, and smoking history. - Highlights: • BMI is inversely associated with emphysema depicted on CT. • Emphysema severity in men was higher than that in women. • ∼50% of the subjects with COPD in our dataset were either overweight or obese. • Age and smoking status are not significantly associated with %LAA

  17. Scintigraphic quantitation of gastrointestinal motor activity and transport: Oesophagus and stomach

    International Nuclear Information System (INIS)

    Stacher, G.; Bergmann, H.

    1992-01-01

    For the recognition and characterisation of oesophageal motor disorders, manometry represents the most reliable tool but yields no information on bolus transport. The transport can be quantitated by radionuclide techniques. The patient is positioned supine beneath a gamma-camera and instructed to swallow a radiolabelled bolus in a single gulp. Using a marker over the cricoid and the activity in the stomach as landmarks, regions of interest are drawn representing the upper, middle and lower third of the oesophagus and the gastric fundus. Activity-time curves enable one to recognise the clearance patterns in these regions. In combination, manometric and radionuclide transit studies recognise a higher number of motor disorders than either procedure alone. Radionuclide methods also are the most reliable and sensitive to quantitate gastric emptying. Procedure, meal size and composition as well as patient position must be standardised and correction techniques applied. The emptying of solid and liquid meal constituents can be evaluated concomitantly. Solids start to empty only after a lag phase of varying extent. With semi-solid meals, which are emptied at the same rate as solid meals of identical composition in the postlag phase, the recording time can be considerably shorter. Besides gastric emptying, the amplitude, frequency and propagation velocity of antral contractions can be recorded using serial images of short frame time and specially devised analytic techniques. (orig.)

  18. Scintigraphic quantitation of gastrointestinal motor activity and transport: Oesophagus and stomach

    Energy Technology Data Exchange (ETDEWEB)

    Stacher, G.; Bergmann, H. (Vienna Univ. (Austria). Psychiatrische Klinik Vienna Univ. (Austria). 1. Chirurgische Klinik Ludwig-Boltzmann-Institut fuer Nuklearmedizin, Vienna (Austria))

    1992-09-01

    For the recognition and characterisation of oesophageal motor disorders, manometry represents the most reliable tool but yields no information on bolus transport. The transport can be quantitated by radionuclide techniques. The patient is positioned supine beneath a gamma-camera and instructed to swallow a radiolabelled bolus in a single gulp. Using a marker over the cricoid and the activity in the stomach as landmarks, regions of interest are drawn representing the upper, middle and lower third of the oesophagus and the gastric fundus. Activity-time curves enable one to recognise the clearance patterns in these regions. In combination, manometric and radionuclide transit studies recognise a higher number of motor disorders than either procedure alone. Radionuclide methods also are the most reliable and sensitive to quantitate gastric emptying. Procedure, meal size and composition as well as patient position must be standardised and correction techniques applied. The emptying of solid and liquid meal constituents can be evaluated concomitantly. Solids start to empty only after a lag phase of varying extent. With semi-solid meals, which are emptied at the same rate as solid meals of identical composition in the postlag phase, the recording time can be considerably shorter. Besides gastric emptying, the amplitude, frequency and propagation velocity of antral contractions can be recorded using serial images of short frame time and specially devised analytic techniques. (orig.).

  19. Sensitivity of radiographic features and specificity of scintigraphic imaging in hand osteoarthritis

    International Nuclear Information System (INIS)

    Buckland-Wright, J.C.; MacFarlane, D.G.; Lynch, J.A.

    1995-01-01

    We undertook to determine which of the radiographic features most reliably detected the presence and disease progression in osteoarthritis in the hand; and which of the radiographic features corresponded with the radionuclide bone scan images. 32 patients with osteoarthritis had X5 macroradiographs taken of their wrists and hands at 6 monthly intervals over an 18 month period. The high magnification and resolution of microfocal radiography permitted quantitative detection of the extent and change in joint space width, subchondral sclerosis, osteophytosis and juxtaarticular radiolucencies. 4-hour technetium 99 m methylene bisphophonate bone scans were taken at 0 and 12 months and the activity of the tracer uptake at each joint scored. The latter was compared with the radiographic features at each visit and the changes between visits analysed. In hand OA the most sensitive radiographic parameters for detecting disease were osteophytes, subchondral sclerosis and justaarticular radiolucencies, with radionuclide imaging demonstrating the increased activity in bone formation associated with the growth and remodelling of osteophytes. Changes in the number and size of osteophytes and joint space narrowing were the only reliable and sensitive parameters for assessing disease progression. We conclude that in osteoarthritis, the bony changes progress significantly before the occurrence of radiographically evident joint space narrowing indicative of cartilage thinning. (authors). 48 refs., 2 tabs., 11 figs

  20. Quantifying emphysema extent from weakly labeled CT scans of the lungs using label proportions learning

    DEFF Research Database (Denmark)

    Ørting, Silas Nyboe; Petersen, Jens; Wille, Mathilde

    2016-01-01

    Quantification of emphysema extent is important in diagnosing and monitoring patients with chronic obstructive pulmonary disease (COPD). Several studies have shown that emphysema quantification by supervised texture classification is more robust and accurate than traditional densitometry. Current...... techniques require highly time consuming manual annotations of patches or use only weak labels indicating overall disease status (e.g, COPD or healthy). We show how visual scoring of regional emphysema extent can be exploited in a learning with label proportions (LLP) framework to both predict presence...... of emphysema in smaller patches and estimate regional extent. We evaluate performance on 195 visually scored CT scans and achieve an intraclass correlation of 0.72 (0.65–0.78) between predicted region extent and expert raters. To our knowledge this is the first time that LLP methods have been applied...

  1. Usefulness of bone scintigraphic classification and quantitative evaluation of bone mineralization with X-CT and SPECT in renal osteodystrophy

    International Nuclear Information System (INIS)

    Okamura, Terue; Fukuda, Teruo; Inoue, Yuuichi; Koizumi, Yoshiko; Ikeda, Hozumi; Ochi, Hironobu

    1987-01-01

    1. Bone scintigraphy with Tc-99m-MDP was performed on 52 patients with chronic renal failure. These bone scintigrams were classified into 4 groups, each of which was correlated to laboratory data and quantitative data of bone mineralization. Group I (32 patients) showed high accumulation of Tc-99m-MDP in the bone. High level of Alk-Pase and c-PTH, low BMC/BW, low EMI number and high radionuclide activity ratio (RN ratio) were observed. Group II (9 patients) demonstrated nuclear bone images with high background activity. RN ratio was slightly higher than the normal. Group III (11 patients) showed extraosseous accumulation of Tc-99m-MDP in the lung, kidney or soft tissues. One patient belonged to Group I. High level of Ca x P product and slightly high RN ratio were observed. In both Group II and III, BMC/BW and EMI number were normal. Group IV (one patient) showed normal skeletal activity on bone scintigram. The mean duration of hemodialysis was the longest in Group I. Our scintigraphic classification is convenient and might contribute an understanding of patho-physiological bone changes in such patients. 2. Subtotal parathyroidectomy (S-PTX) was employed in 18 of 52 patients on chronic renal failure with secondary hyperparathyroidism. These patients were studied before and after S-PTX using 6 different procedures; conventional radiography, microdensitometry, bone mineral analysis, measurement of EMI number with X-CT (frontal bone), bone scintigraphy, and RN ratio (frontal bone/brain) with SPECT. On the bone scan, the diffuse increased activity in the calvarium became less prominent after S-PTX in all 18 patients. We devised a new method to quantify the bone changes revealed by the bone scan; the RN ratio with SPECT. The ratio decreased markedly after surgery. This method seems to be most useful for detecting dynamic bone changes sensitively and quantitatively. (author)

  2. Comparison of Duke ergo-metric score and of the classification based on scintigraphic data in the stratification of coronaries

    International Nuclear Information System (INIS)

    Ouhayoun, E.; Coca, F.J.; Payoux, P.; Tafani, J.A.M.; Esquerre, J.P.

    1997-01-01

    Stratification of risk (sudden death and infarction) remains a major problem of the way the coronaries are cared. Since 1987, a score based on the test-to-effort data was proposed by Mark and coll. of 'Duke University' team. They tried to demonstrate that this score provides a reliable classification of patients. We have compared the results obtained by using this score with those issued from the simultaneous analysis of the left ventricle (LV) function and LV perfusion. A hundred patients afflicted with coronaries (stenoses > 50%) benefited by a coupled study of the LV function and perfusion at rest and under effort made by means of MIBI scintigraphy. The effort test allowed calculating the 'Duke' score by means of a formula in terms of the angor index defined as follows: 0 for absence, 1 for angor and 2 for angor motivating cessation. According to Duke score three classes can be defined: patients of low risk, score ≥ 5; patients of intermediate risk, score in between 5 and -10; patients of high risk, score ≤ -10. Ejection fraction at effort acme was measured in every patient as well as the extension of perfusion defect, evaluated semi-quantitatively at effort and rest on the basis of bull's eye. Three groups of patients were created according to the results of perfusion+function couple): (A)- normal perfusion and function, the case of good prognostication; (B)- patients slightly afflicted (FEV effort > 50% and in-effort defect extension effort 50%). The last criteria were proved by several studies as bad prognostication. A table presents the risks according the Duke score for the three classes. One can observe that one third of the patients severely afflicted by confirmed ischemia are classified in the low-risk class. Besides, the majority of patients are ranked with intermediary risk, independently of scintigraphic results. In conclusion, these results concerning the stratification of coronaries show the superiority of the criteria based on scintigraphy over

  3. Scintigraphic evaluation of soft tissue tumors with technetium(V)-99m dimercaptosuccinic acid, a new tumor seeking radiopharmaceutical

    International Nuclear Information System (INIS)

    Ohta, H.; Yoshizumi, M.; Endo, K.; Torizuka, K.; Yokoyama, A.; Yamamoto, K.

    1984-01-01

    Recently, a very promising tumor seeking agent, a Tc(V)-99m dimercaptosuccinic acid (Tc(V)-DMS), which was labelled under optimal pH 8 and very low SnCl/sub 2/ concentrations, has been developed. An equilibrium between a stable form and a dissociated form of anion TcO/sub 4//sup 3-/, structural similarity to PO/sub 4//sup 3-/, postulated for tumor uptake. And the authors have previously reported that Tc(V)-DMS scintigram would be useful in the diagnosis of medullary thyroid carcinoma. In an attempt to widen its applicability, the scintigraphic examinations of soft tissue tumors with Tc(V)-DMS and comparative study with Ga-67 citrate were performed in 58 patients. Scintigrams were made 60-120 min after i.v. administration of 10 mCi Tc(V)-DMS using a conventional gamma camera. Tc(V)-DMS was found to have superior sensitivity of 90% for malignant tumors (including aggressive fibromatosis) to that with Ga-67 citrate of 56%, but inferior specificity of 71% to that with Ga-67 citrate of 80%. And the accuracy of the scan in soft tissue tumors with Tc(V)-DMS and Ga-67 citrate was 78% and 71%, respectively. Although the accumulation of Tc(V)-DMS has been detected in some benign soft tissue tumors and the exact mechanism of Tc(V)-DMS accumulation remains to be elucidated, these data indicated that Tc(V)-DMS scintigraphy would be of great use in the detection of extension or location of malignant soft tissue tumors

  4. Whole-body and pinhole bone scintigraphic manifestations of Reiter`s syndrome: distribution patterns and early and characteristic signs

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung-Hoon; Chung, Soo-Kyo; Park, Young-Ha; Lee, Sung-Yong; Sohn, Hyung-Sun [Department of Nuclear Medicine, Catholic University Hospitals, Seoul (Korea, Republic of); Bahk, Yong-Whee [Department of Radiology, Samsung Cheil Hospital, Sungkyunkwan University College of Medicine, Seoul (Korea, Republic of)

    1999-02-01

    The characteristic whole-body and pinhole scintigraphic manifestations of osteo-enthesopathy and arthropathy in Reiter`s syndrome (RS) are described, with an emphasis on early diagnosis. We analysed 59 sets of whole-body and pinhole bone scintigrams of 59 patients with RS. The population comprised 47 men and 12 women with an age range from 15 to 53 years (mean=29.4). Bone scintigraphy was carried out 2-2.5 h after intravenous injection of technetium-99m hydroxydiphosphonate using a single-head gamma camera (Siemens Orbiter Model 6601) with a low-energy high-resolution and a 4-mm pinhole collimator for whole-body and pinhole scintigraphy, respectively. In total 262 lesions of osteo-enthesopathy and arthritis were detected on 59 whole-body scintigrams, an incidence of 4.4 lesions per patient. As anticipated, the lesional distribution was asymmetrical: 68% were in the lower limb skeleton and 32% in the axial and upper limb skeleton. Pinhole bone scintigraphy, applied selectively to one region of interest in each case, enabled us to accurately diagnose arthritis and osteo-enthesopathy. It was noteworthy that osteo-enthesopathy, alone or in combination with arthritis, occurred in 78.9%, and had a strong predilection for the foot bones, especially the calcaneus (25.6%). Pinhole scintigraphy detected enthesopathy in the absence of radiographic alteration in 14.1% of cases and portrayed characteristic signs of RS in 6.9%. Whole-body bone scintigraphy augmented with pinhole scintigraphy was found to be useful in order to panoramically display the systemic involvement pattern, to assess the characteristic bone and articular alterations and to detect early signs of RS. (orig.) With 10 figs., 3 tabs., 19 refs.

  5. Comparison of de-noising techniques of scintigraphic images; Comparaison de techniques de debruitage des images scintigraphiques

    Energy Technology Data Exchange (ETDEWEB)

    Kirkove, M.; Seret, A. [Liege Univ., Imagerie Medicale Experimentale, Institut de Physique (Belgium)

    2007-05-15

    Scintigraphic images are strongly affected by Poisson noise. This article presents the results of a comparison between de-noising methods for Poisson noise according to different criteria: the gain in signal-to-noise ratio, the preservation of resolution and contrast. and the visual quality. The wavelet techniques recently developed to de-noise Poisson noise limited images are divided into two groups based on: (1) the Haar representation. 1 (2) the transformation of Poisson noise into white Gaussian noise by the Haar-Fisz transform followed by a de-noising. In this study, three variants of the first group and three variants of the second. including the adaptative Wiener filter, four types of wavelet thresholding and the Bayesian method of Pizurica were compared to Metz and Hanning filters and to Shine, a systematic noise elimination process. All these methods, except Shine, are parametric. For each of them, ranges of optimal values for the parameters were highlighted as a function of the aforementioned criteria. The intersection of ranges for the wavelet methods without thresholding was empty, and these methods were therefore not further compared quantitatively. The thresholding techniques and Shine gave the best results in resolution and contrast. The largest improvement in signal-to-noise ratio was obtained by the filters. Ideally, these filters should be accurately defined for each image. This is difficult in the clinical context. Moreover. they generate oscillation artefacts. In addition, the wavelet techniques did not bring significant improvements, and are rather slow. Therefore, Shine, which is fast and works automatically, appears to be an interesting alternative. (authors)

  6. Detection of gastroesophageal reflux in survivors of congenital diaphragmatic hernia: A radionuclide scintigraphic study in 26 children

    International Nuclear Information System (INIS)

    Thomas, E.J.; Bharathi Dasan, J.; Chandrasekhar, N.; Tripathi, M.; Kumar, R.; Kumar, A.; Malhotra, A.; Gupta, D.K.; Mitra, D.K.

    2002-01-01

    Introduction: Anatomical and functional esophageal abnormalities in survivors with CDH are well known. Gastro-esophageal Reflux (GER) is a common cause of long-term morbidity in survivors of congenital diaphragmatic hernia. The incidence of GER in these patients varies from 20-70% using various modalities. Aims: The present retrospective analysis was undertaken to find out the incidence of GER detected by radionuclide scintigraphy in survivors of congenital diaphragmatic hernia. Materials and Methods: Radionuclide scintigraphy for GER detection were performed in 26 survivors of congenital diaphragmatic hernia (17 male and 9 female) with a mean age of 19 months; age range 10 days to 56 months. Seven of the children had symptoms suggestive of GER. Of these 7, 3 had recurrent respiratory tract infection, 2 had regurgitation, 1 had vomiting and 1 had epigastric pain. The remaining 19 children were referred as part of routine follow up. All the children underwent radionuclide scintigraphy with 100-200 micro curie (3.7 -7.4MBq) of Tc99m-Sulphur Colloid. Results: The radionuclide scintigraphy detected GER in 11 out of 26(42.3%) children. Among the 7 symptomatic children, 4 (57%) had positive scintigraphic studies for reflux. Of these 4, 3(75%) had proximal reflux and 1 had distal reflux. Of the 19 asymptomatic patients, 7 (37%) were positive for GER on scintigraphy. Of these 7, 4 (57%) had proximal reflux and 3 (43%) had distal reflux. Conclusions: There is high incidence of GER in survivors of congenital diaphragmatic hernia irrespective of the presence or absence of symptoms suggestive of GER. Scintiscanning being a simple, noninvasive test can be used for initial evaluation of survivors of CDH for GER

  7. Error and corrections with scintigraphic measurement of gastric emptying of solid foods

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, J.H.; Van Deventer, G.; Graham, L.S.; Thomson, J.; Thomasson, D.

    1983-03-01

    Previous methods for correction of depth used geometric means of simultaneously obtained anterior and posterior counts. The present study compares this method with a new one that uses computations of depth based on peak-to-scatter (P:S) ratios. Six normal volunteers were fed a meal of beef stew, water, and chicken liver that had been labeled in vivo with both In-113m and Tc-99m. Gastric emptying was followed at short intervals with anterior counts of peak and scattered radiation for each nuclide, as well as posteriorly collected peak counts from the gastric ROI. Depth of the nuclides was estimated by the P:S method as well as the older method. Both gave similar results. Errors from septal penetration or scatter proved to be a significantly larger problem than errors from changes in depth.

  8. The skeletal changes of progressive systemic scleroderma (PSS), of exclusive Raynaud phenomenon and of circumscript scleroderma in a gamma camera scintigraph

    International Nuclear Information System (INIS)

    Ulbrich, T.

    1987-01-01

    The bases of this study are the skeletal scintigraphs of altogether 34 patients with the three forms of scleroderma mentioned in the title. The PSS shows a polytropic, symmetric distribution pattern, the exclusive Raynaud's phenomenon shows a basic skeleton which is unchanged in contrast to circumscript scleroderma, with which also the larger joints are relatively more frequently attacked than the little ones. As a result of high sensitivity skeletal scintiscanning makes possible an early recognition of osseous changes and is there with superior to X-radiology and should then see an increased use for the clarification of the diagnosis of arthropathy in scleroderma. (TRV) [de

  9. Prospective scintigraphic study of avascular necrosis of bone in renal transplant patients

    International Nuclear Information System (INIS)

    Spencer, J.D.; Maisey, M.

    1985-01-01

    Avascular necrosis of bone (AVN) may cripple a patient who has had a successful renal transplant. The authors have attempted to gain more knowledge of this condition by undertaking a prospective survey to determine as accurately as possible the incidence of AVN in renal transplant patients. Routine six-month whole body bone scans were performed with /sup 99m/Technetium Methylene Diphosphonate in 42 consecutive surviving renal transplant patients. The survey started in 1978-79, and patients were followed for a minimum of two years and a maximum of three years. As a result, seven were found to have AVN that would have remained undetected in two of the patients if routine whole body bone scanning had not been conducted. Despite a reduction in steroid dosage in recent years, the incidence of AVN in the authors patients remains high at 17%. Bone scan appearances in renal transplant patients were classified and subdivided into four groups. By linking bone scans and radiographic and postmortem appearances of the femoral head, one very early case of AVN was detected. Routine bone scanning provided a more accurate estimation of the incidence of fractures in renal transplant patients

  10. A method for determining the extent of thermal burns in elephants

    Directory of Open Access Journals (Sweden)

    A. Shakespeare

    2006-06-01

    Full Text Available A practical method was developed to assess the extent of burns suffered by elephants caught in bush fires. In developing this method, the surface areas of the different body parts of juvenile, subadult and adult elephants were first determined using standard equations, and then expressed as a percentage of the total body surface area. When viewed from a distance, the burnt proportion of all body segments is estimated, converted to percentages of total body surface area, and then summed to determine the extent of burns suffered.

  11. Factors influencing the spatial extent of mobile source air pollution impacts: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Levy Jonathan I

    2007-05-01

    Full Text Available Abstract Background There has been growing interest among exposure assessors, epidemiologists, and policymakers in the concept of "hot spots", or more broadly, the "spatial extent" of impacts from traffic-related air pollutants. This review attempts to quantitatively synthesize findings about the spatial extent under various circumstances. Methods We include both the peer-reviewed literature and government reports, and focus on four significant air pollutants: carbon monoxide, benzene, nitrogen oxides, and particulate matter (including both ultrafine particle counts and fine particle mass. From the identified studies, we extracted information about significant factors that would be hypothesized to influence the spatial extent within the study, such as the study type (e.g., monitoring, air dispersion modeling, GIS-based epidemiological studies, focus on concentrations or health risks, pollutant under study, background concentration, emission rate, and meteorological factors, as well as the study's implicit or explicit definition of spatial extent. We supplement this meta-analysis with results from some illustrative atmospheric dispersion modeling. Results We found that pollutant characteristics and background concentrations best explained variability in previously published spatial extent estimates, with a modifying influence of local meteorology, once some extreme values based on health risk estimates were removed from the analysis. As hypothesized, inert pollutants with high background concentrations had the largest spatial extent (often demonstrating no significant gradient, and pollutants formed in near-source chemical reactions (e.g., nitrogen dioxide had a larger spatial extent than pollutants depleted in near-source chemical reactions or removed through coagulation processes (e.g., nitrogen oxide and ultrafine particles. Our illustrative dispersion model illustrated the complex interplay of spatial extent definitions, emission rates

  12. Assessing the extent of non-stationary biases in GCMs

    Science.gov (United States)

    Nahar, Jannatun; Johnson, Fiona; Sharma, Ashish

    2017-06-01

    General circulation models (GCMs) are the main tools for estimating changes in the climate for the future. The imperfect representation of climate models introduces biases in the simulations that need to be corrected prior to their use for impact assessments. Bias correction methods generally assume that the bias calculated over the historical period does not change and can be applied to the future. This study investigates this assumption by considering the extent and nature of bias non-stationarity using 20th century precipitation and temperature simulations from six CMIP5 GCMs across Australia. Four statistics (mean, standard deviation, 10th and 90th quantiles) in monthly and seasonal biases are obtained for three different time window lengths (10, 25 and 33 years) to examine the properties of bias over time. This approach is repeated for two different phases of the Interdecadal Pacific Oscillation (IPO), which is known to have strong influences on the Australian climate. It is found that bias non-stationarity at decadal timescales is indeed an issue over some of Australia for some GCMs. When considering interdecadal variability there are significant difference in the bias between positive and negative phases of the IPO. Regional analyses confirmed these findings with the largest differences seen on the east coast of Australia, where IPO impacts tend to be the strongest. The nature of the bias non-stationarity found in this study suggests that it will be difficult to modify existing bias correction approaches to account for non-stationary biases. A more practical approach for impact assessments that use bias correction maybe to use a selection of GCMs where the assumption of bias non-stationarity holds.

  13. The extent of continental crust beneath the Seychelles

    Science.gov (United States)

    Hammond, J. O. S.; Kendall, J.-M.; Collier, J. S.; Rümpker, G.

    2013-11-01

    The granitic islands of the Seychelles Plateau have long been recognised to overlie continental crust, isolated from Madagascar and India during the formation of the Indian Ocean. However, to date the extent of continental crust beneath the Seychelles region remains unknown. This is particularly true beneath the Mascarene Basin between the Seychelles Plateau and Madagascar and beneath the Amirante Arc. Constraining the size and shape of the Seychelles continental fragment is needed for accurate plate reconstructions of the breakup of Gondwana and has implications for the processes of continental breakup in general. Here we present new estimates of crustal thickness and VP/VS from H-κ stacking of receiver functions from a year long deployment of seismic stations across the Seychelles covering the topographic plateau, the Amirante Ridge and the northern Mascarene Basin. These results, combined with gravity modelling of historical ship track data, confirm that continental crust is present beneath the Seychelles Plateau. This is ˜30-33 km thick, but with a relatively high velocity lower crustal layer. This layer thins southwards from ˜10 km to ˜1 km over a distance of ˜50 km, which is consistent with the Seychelles being at the edge of the Deccan plume prior to its separation from India. In contrast, the majority of the Seychelles Islands away from the topographic plateau show no direct evidence for continental crust. The exception to this is the island of Desroche on the northern Amirante Ridge, where thicker low density crust, consistent with a block of continental material is present. We suggest that the northern Amirantes are likely continental in nature and that small fragments of continental material are a common feature of plume affected continental breakup.

  14. Scintigraphic changes of osteoarthritis: An analysis of findings during routine bone scans to evaluate the incidence in an Indian population

    International Nuclear Information System (INIS)

    Samuel, Aban M; Jain, HM

    2012-01-01

    The reported prevalence of osteoarthritis (OA) varies according to the method that is used to detect it. X-rays are commonly used in the diagnosis of OA. However, marked osteoarthritic damage must be present to detect characteristic changes with radiologic imaging. Our intention was to evaluate bone scans (1) he occurrence of such changes, (2) he incidence of OA (single or multiple joints) in the general population (a mixture of urban and rural) who were asymptomatic. Data on OA incidence in India is sketchy and sparse as against more detailed information obtained from USA and European nations. Also, clinical rheumatologists are not well-versed with the potential application of bone scans in the management of arthritides. Two hundred and eighty nine planar images of routine bone scans were randomly evaluated by two trained nuclear medicine physicians. The ages of the patients ranged from 20 to over 80 years. It is observed that as the age increases, the incidence of joint involvement increases. However, it is worth noting that even in the age group of 20-40 years, as many as 34% of asymptomatic persons have involvement of the joints. In this age group, as the manifestation is probably in the inception stage, there is a tendency for single joint involvement as against multiple joints seen in the older age groups. Another point to note is that the incidence of joint involvement was not affected by weight. In our patient population, gross obesity was not seen. The predominant joints involved are the knees and hips, followed by the shoulders and ankles. Females show a higher incidence than males. Some patients would be having only a single site or multiple site involvement. This observation is important as in a single, simple test whole body survey gives more information with low radiation burden. Scintigraphic prevalence of OA is higher than reported in US, Europe, and Asia as this test is more sensitive in detecting early changes as compared to radiological changes

  15. Relevance of 123I-BMIPP delayed scintigraphic imaging for patients with angina pectoris – a pilot study

    Science.gov (United States)

    Koyama, Kohei; Akashi, Yoshihiro J.; Kida, Keisuke; Suzuki, Kengo; Ishibashi, Yuki; Musha, Haruki; Banach, Maciej

    2011-01-01

    Introduction The study was designed to clarify the role of 123I-β-methyl-iodophenylpentadecanoic acid (123I-BMIPP) in the evaluation of myocardial fatty acid metabolism in patients with stable angina pectoris (AP) before and after percutaneous coronary intervention (PCI). Material and methods Ten controls (mean age: 70.4 ±10.5 years) and 12 patients with AP (mean age: 67.4 ±11.6 years) and single vessel coronary artery disease participated in the radionuclide cardiac study. Scintigraphic images were acquired at 30 min and at 4 h after 123I-BMIPP injection to determine early and delayed BMIPP uptake, respectively. The heart-to-mediastinum (H/M) ratio and the washout rate (WR) were calculated from the planar images. All patients underwent scintigraphy one day before PCI and again 1 month after successful PCI. Results No significant differences in the early or delayed H/M ratios were observed between the patients and the controls before PCI (early: 2.70 ±0.36 vs. 2.73 ±0.57; delayed: 2.26 ±0.33 vs. 2.40 ±0.43; p > 0.2 for both). The early and delayed H/M ratios remained unchanged with the comparison with before PCI (early: 2.72 ±0.27, delayed: 2.23 ±0.22; p > 0.2 for both). The global WR before PCI was significantly higher in the patients than in the control group (36.7 ±9.3%, vs. 28.1 ±8.2%, p = 0.02). However, the WR after PCI did not significantly differ between the patients and the controls (34.3 ±7.8% vs. 28.1 ±8.2%, p = 0.1). Conclusions These data may suggest that the WR of 123I-BMIPP determined from the planar images enhances the presence of myocardial ischaemia. PMID:22295024

  16. The development of estimated methodology for interfacial adhesion of semiconductor coatings having an enormous mismatch extent

    Science.gov (United States)

    Lee, Chang-Chun; Huang, Pei-Chen

    2018-05-01

    The long-term reliability of multi-stacked coatings suffering the bending or rolling load was a severe challenge to extend the lifespan of foregoing structure. In addition, the adhesive strength of dissimilar materials was regarded as the major mechanical reliability concerns among multi-stacked films. However, the significant scale-mismatch from several nano-meter to micro-meter among the multi-stacked coatings causing the numerical accuracy and converged capability issues on fracture-based simulation approach. For those reasons, this study proposed the FEA-based multi-level submodeling and multi-point constraint (MPC) technique to conquer the foregoing scale-mismatch issue. The results indicated that the decent region of first and second-order submodeling can achieve the small error of 1.27% compared with the experimental result and significantly reduced the mesh density and computing time. Moreover, the MPC method adopted in FEA simulation also shown only 0.54% error when the boundary of selected local region was away the concerned critical region following the Saint-Venant principle. In this investigation, two FEA-based approaches were used to conquer the evidently scale mismatch issue when the adhesive strengths of micro and nano-scale multi-stacked coating were taken into account.

  17. Estimating the extent and structure of trade in horticultural orchids via social media.

    Science.gov (United States)

    Hinsley, Amy; Lee, Tamsin E; Harrison, Joseph R; Roberts, David L

    2016-10-01

    The wildlife trade is a lucrative industry involving thousands of animal and plant species. The increasing use of the internet for both legal and illegal wildlife trade is well documented, but there is evidence that trade may be emerging on new online technologies such as social media. Using the orchid trade as a case study, we conducted the first systematic survey of wildlife trade on an international social-media website. We focused on themed forums (groups), where people with similar interests can interact by uploading images or text (posts) that are visible to other group members. We used social-network analysis to examine the ties between 150 of these orchid-themed groups to determine the structure of the network. We found 4 communities of closely linked groups based around shared language. Most trade occurred in a community that consisted of English-speaking and Southeast Asian groups. In addition to the network analysis, we randomly sampled 30 groups from the whole network to assess the prevalence of trade in cultivated and wild plants. Of 55,805 posts recorded over 12 weeks, 8.9% contained plants for sale, and 22-46% of these posts pertained to wild-collected orchids. Although total numbers of posts about trade were relatively small, the large proportion of posts advertising wild orchids for sale supports calls for better monitoring of social media for trade in wild-collected plants. © 2016 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.

  18. Human activities on the deep seafloor in the North East Atlantic: an assessment of spatial extent.

    Directory of Open Access Journals (Sweden)

    Angela R Benn

    Full Text Available BACKGROUND: Environmental impacts of human activities on the deep seafloor are of increasing concern. While activities within waters shallower than 200 m have been the focus of previous assessments of anthropogenic impacts, no study has quantified the extent of individual activities or determined the relative severity of each type of impact in the deep sea. METHODOLOGY: The OSPAR maritime area of the North East Atlantic was chosen for the study because it is considered to be one of the most heavily impacted by human activities. In addition, it was assumed data would be accessible and comprehensive. Using the available data we map and estimate the spatial extent of five major human activities in the North East Atlantic that impact the deep seafloor: submarine communication cables, marine scientific research, oil and gas industry, bottom trawling and the historical dumping of radioactive waste, munitions and chemical weapons. It was not possible to map military activities. The extent of each activity has been quantified for a single year, 2005. PRINCIPAL FINDINGS: Human activities on the deep seafloor of the OSPAR area of the North Atlantic are significant but their footprints vary. Some activities have an immediate impact after which seafloor communities could re-establish, while others can continue to make an impact for many years and the impact could extend far beyond the physical disturbance. The spatial extent of waste disposal, telecommunication cables, the hydrocarbon industry and marine research activities is relatively small. The extent of bottom trawling is very significant and, even on the lowest possible estimates, is an order of magnitude greater than the total extent of all the other activities. CONCLUSIONS/SIGNIFICANCE: To meet future ecosystem-based management and governance objectives for the deep sea significant improvements are required in data collection and availability as well as a greater awareness of the relative impact of

  19. Reconstructed North American Snow Extent, 1900-1993

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains reconstructed monthly North American snow extent values for November through March, 1900-1993. Investigators used a combination of satellite...

  20. Exploring the extent to which ELT students utilise smartphones for ...

    African Journals Online (AJOL)

    Zehra

    2015-11-09

    Nov 9, 2015 ... aimed to explore the extent to which English Language Teaching (ELT) students utilise ... Given the fact that almost all students have a personal smartphone, and use it ..... ears as a disadvantage for smartphones (Kétyi,.

  1. To what extent do food purchases reflect shoppers? diet quality and nutrient intake?

    OpenAIRE

    Appelhans, Bradley M.; French, Simone A.; Tangney, Christy C.; Powell, Lisa M.; Wang, Yamin

    2017-01-01

    Background Food purchasing is considered a key mediator between the food environment and eating behavior, and food purchasing patterns are increasingly measured in epidemiologic and intervention studies. However, the extent to which food purchases actually reflect individuals? dietary intake has not been rigorously tested. This study examined cross-sectional agreement between estimates of diet quality and nutrient densities derived from objectively documented household food purchases and thos...

  2. Scintigraphic findings on 99mTc-MDP, 99mTc-sestamibi and 99mTc-HMPAO images in Gaucher's disease

    International Nuclear Information System (INIS)

    Mariani, G.; Molea, N.; La Civita, L.; Porciello, G.; Lazzeri, E.; Ferri, C.

    1996-01-01

    We report here on the use of the lipophilic cationic complex technetium-99m sestamibi ( 99m Tc-MIBI), employed as an indicator of increased cellular density and metabolic activity, to evaluate Gaucher cell infiltrates in the bone marrow; 99m Tc-hexametazime ( 99m Tc-HMPAO) was also employed, as a pure indicator of lipidic infiltration in the bone marrow. A 67-year-old patient with known type 1 Gaucher's disease presented with a painful left hip and knee and difficulty in gait subsequent to traumatic fracture of the left femoral neck that had required implant of a fixation screw-plaque. Bone scan with 99m Tc-methylene diphosphonate revealed reduced uptake at the distal metaphyseal-epiphyseal femoral region. In addition, whole-body maps and spot-view acquisitions of the thighs and legs were recorded at both 30 min and 2.5 h after the injection of 99m Tc-MIBI: the scintigraphic pattern clearly showed increased uptake at several sites involved by Gaucher deposits in the bone marrow (both knees, with variable intensity in different areas), matching the bone changes detected by conventional x-ray. The target to non-target ratios slowly decreased with time, from an average value of 2.25 in the early scan to an average value of 2 in the delayed scan. The lipid-soluble agent 99m Tc-HMPAO exhibited a superimposable scintigraphic pattern of accumulation at the involved sites, though with lower target to non-target ratios (1.27-1.48). The results obtained in this patient suggest a potential role of 99m Tc-MIBI in the scintigraphic evaluation of Gaucher's lipid deposits in the bone marrow. If the results are confirmed in other patients, this radiopharmaceutical would offer clear advantages over 133 Xe because of its wider availability and greater practicality (i.v. administration of 99m Tc-MIBI versus inhalation of 133 Xe, and use of a single gamma camera instead of two as with 133 Xe). (orig.). With 3 figs

  3. Fast renal trapping of porcine Luteinizing Hormone (pLH shown by 123I-scintigraphic imaging in rats explains its short circulatory half-life

    Directory of Open Access Journals (Sweden)

    Locatelli Alain

    2003-10-01

    Full Text Available Abstract Background Sugar moieties of gonadotropins play no primary role in receptor binding but they strongly affect their circulatory half-life and consequently their in vivo biopotencies. In order to relate more precisely hepatic trapping of these glycoproteic hormones with their circulatory half-life, we undertook a comparative study of the distribution and elimination of porcine LH (pLH and equine CG (eCG which exhibit respectively a short and a long half-life. This was done first by following half-lives of pLH in piglets with hepatic portal circulation shunted or not. It was expected that such a shunt would enhance the short half-life of pLH. Subsequently, scintigraphic imaging of both 123I-pLH and 123I-eCG was performed in intact rats to compare their routes and rates of distribution and elimination. Methods Native pLH or eCG was injected to normal piglets and pLH was tested in liver-shunted anæsthetized piglet. Blood samples were recovered sequentially over one hour time and the hormone concentrations were determined by a specific ELISA method. Scintigraphic imaging of 123I-pLH and 123I-eCG was performed in rats using a OPTI-CGR gamma camera. Results In liver-shunted piglets, the half-life of pLH was found to be as short as in intact piglets (5 min. In the rat, the half-life of pLH was also found to be very short (3–6 min and 123I-pLH was found to accumulate in high quantity in less than 10 min post injection at the level of kidneys but not in the liver. 123I-eCG didn't accumulate in any organ in the rats during the first hour, plasma concentrations of this gonadotropin being still elevated (80% at this time. Conclusion In both the porcine and rat species, the liver is not responsible for the rapid elimination of pLH from the circulation compared to eCG. Our scintigraphic experiments suggest that the very short circulatory half-life of LH is due to rapid renal trapping.

  4. Extent of Cropland and Related Soil Erosion Risk in Rwanda

    Directory of Open Access Journals (Sweden)

    Fidele Karamage

    2016-06-01

    Full Text Available Land conversion to cropland is one of the major causes of severe soil erosion in Africa. This study assesses the current cropland extent and the related soil erosion risk in Rwanda, a country that experienced the most rapid population growth and cropland expansion in Africa over the last decade. The land cover land use (LCLU map of Rwanda in 2015 was developed using Landsat-8 imagery. Based on the obtained LCLU map and the spatial datasets of precipitation, soil properties and elevation, the soil erosion rate of Rwanda was assessed at 30-m spatial resolution, using the Revised Universal Soil Loss Equation (RUSLE model. According to the results, the mean soil erosion rate was 250 t·ha−1·a−1 over the entire country, with a total soil loss rate of approximately 595 million tons per year. The mean soil erosion rate over cropland, which occupied 56% of the national land area, was estimated at 421 t·ha−1·a−1 and was responsible for about 95% of the national soil loss. About 24% of the croplands in Rwanda had a soil erosion rate larger than 300 t·ha−1·a−1, indicating their unsuitability for cultivation. With a mean soil erosion rate of 1642 t·ha−1·a−1, these unsuitable croplands were responsible for 90% of the national soil loss. Most of the unsuitable croplands are distributed in the Congo Nile Ridge, Volcanic Range mountain areas in the west and the Buberuka highlands in the north, regions characterized by steep slopes (>30% and strong rainfall. Soil conservation practices, such as the terracing cultivation method, are paramount to preserve the soil. According to our assessment, terracing alone could reduce the mean cropland soil erosion rate and the national soil loss by 79% and 75%, respectively. After terracing, only a small proportion of 7.6% of the current croplands would still be exposed to extreme soil erosion with a rate >300 t·ha−1·a−1. These irremediable cropland areas should be returned to mountain forest to

  5. A Fully Automated Classification for Mapping the Annual Cropland Extent

    Science.gov (United States)

    Waldner, F.; Defourny, P.

    2015-12-01

    Mapping the global cropland extent is of paramount importance for food security. Indeed, accurate and reliable information on cropland and the location of major crop types is required to make future policy, investment, and logistical decisions, as well as production monitoring. Timely cropland information directly feed early warning systems such as GIEWS and, FEWS NET. In Africa, and particularly in the arid and semi-arid region, food security is center of debate (at least 10% of the population remains undernourished) and accurate cropland estimation is a challenge. Space borne Earth Observation provides opportunities for global cropland monitoring in a spatially explicit, economic, efficient, and objective fashion. In the both agriculture monitoring and climate modelling, cropland maps serve as mask to isolate agricultural land for (i) time-series analysis for crop condition monitoring and (ii) to investigate how the cropland is respond to climatic evolution. A large diversity of mapping strategies ranging from the local to the global scale and associated with various degrees of accuracy can be found in the literature. At the global scale, despite efforts, cropland is generally one of classes with the poorest accuracy which make difficult the use for agricultural. This research aims at improving the cropland delineation from the local scale to the regional and global scales as well as allowing near real time updates. To that aim, five temporal features were designed to target the key- characteristics of crop spectral-temporal behavior. To ensure a high degree of automation, training data is extracted from available baseline land cover maps. The method delivers cropland maps with a high accuracy over contrasted agro-systems in Ukraine, Argentina, China and Belgium. The accuracy reached are comparable to those obtained with classifiers trained with in-situ data. Besides, it was found that the cropland class is associated with a low uncertainty. The temporal features

  6. Scintigraphic examinations in neuroradiology

    Energy Technology Data Exchange (ETDEWEB)

    Emde, H [Universitaet des Saarlandes, Homburg/Saar (Germany, F.R.). Abt. fuer Neuroradiologie

    1979-06-01

    The introduction of CT in neuroradiological diagnostics has clearly lowered the interest in nuclear examinations. Frequently, these are carried only out of a lack of CT capacity. Still, some examples are given to show how useful cerebral, bone, and cerebrospinal fluid scintiscanning can be in every day routine diagnostics.

  7. Usefulness of exercise electrocardiography and thallium scintigraphy in unstable angina pectoris in predicting the extent and severity of coronary artery disease

    International Nuclear Information System (INIS)

    Freeman, M.R.; Chisholm, R.J.; Armstrong, P.W.

    1988-01-01

    The safety and efficacy of exercise electrocardiography and thallium scintigraphy early in the course of unstable angina pectoris were assessed 4.6 +/- 1.6 days after admission in 67 patients with unstable angina that stabilized after medical therapy. Coronary arteriography was performed in all patients 5.4 +/- 2.4 days after admission. There was no difference in clinical, exercise or scintigraphic variables between patients with stenoses less than 50% and patients with 1-vessel coronary artery disease (CAD) defined as a diameter stenosis greater than or equal to 50%. Patients with 3-vessel CAD had a significantly shorter exercise duration than patients with less than 50%-diameter narrowing (5.5 +/- 2.2 vs 8.3 +/- 3.3 minutes, respectively), lower exercise heart rate (119 +/- 20 vs 149 +/- 22 beats/min) and systolic blood pressure (156 +/- 29 vs 166 +/- 33 mm Hg), more frequent chest pain (76 vs 20%) and more pronounced ST depression (-1.48 +/- 1.37 vs -0.33 +/- 0.72 mm). In addition, thallium defect size on exercise was greater in the patients with 2-vessel CAD (159 +/- 132 degrees) and 3-vessel CAD (255 +/- 132 degrees) than in patients with no CAD (28 +/- 319 degrees) or 1-vessel CAD (73 +/- 78 degrees), p greater than or equal to 0.05. Multiple regression analysis demonstrated that thallium defect size was the best predictor of extent of CAD, with exercise heart rate and presence of chest pain during exercise also predictive of extent of CAD

  8. Extent and kinetics of recovery of occult spinal cord injury

    International Nuclear Information System (INIS)

    Ang, K. Kian; Jiang, G.-L.; Feng Yan; Stephens, L. Clifton; Tucker, Susan L.; Price, Roger E.

    2001-01-01

    Purpose: To obtain clinically useful quantitative data on the extent and kinetics of recovery of occult radiation injury in primate spinal cord, after a commonly administered elective radiation dose of 44 Gy, given in about 2 Gy per fraction. Methods and Materials: A group of 56 rhesus monkeys was assigned to receive two radiation courses to the cervical and upper thoracic spinal cord, given in 2.2 Gy per fraction. The dose of the initial course was 44 Gy in all monkeys. Reirradiation dose was 57.2 Gy, given after 1-year (n 16) or 2-year (n = 20) intervals, or 66 Gy, given after 2-year (n = 4) or 3-year (n = 14) intervals. Two animals developed intramedullary tumors before reirradiation and, therefore, did not receive a second course. The study endpoint was myeloparesis, manifesting predominantly as lower extremity weakness and decrease in balance, occurring within 2.5 years after reirradiation, complemented by histologic examination of the spinal cord. The data obtained were analyzed along with data from a previous study addressing single-course tolerance, and data from a preliminary study of reirradiation tolerance. Results: Only 4 of 45 monkeys completing the required observation period (2-2.5 years after reirradiation, 3-5.5 years total) developed myeloparesis. The data revealed a substantial recovery of occult injury induced by 44 Gy within the first year, and suggested additional recovery between 1 and 3 years. Fitting the data with a model, assuming that all (single course and reirradiation) dose-response curves were parallel, yielded recovery estimates of 33.6 Gy (76%), 37.6 Gy (85%), and 44.6 Gy (101%) of the initial dose, after 1, 2, and 3 years, respectively, at the 5% incidence (D 5 ) level. The most conservative estimate, using a model in which it was assumed that there was no recovery between 1 and 3 years following initial irradiation and that the combined reirradiation curve was not necessarily parallel to the single-course curve, still showed an

  9. Diagnostic accuracy of scintigraphic methods in the differential diagnosis of focal liver lesions. Stellenwert nuklearmedizinischer Methoden in der Differentialdiagnose solider Leberherde

    Energy Technology Data Exchange (ETDEWEB)

    Czermak, H. (Nuklearmedizinische Abt., LKH Klagenfurt (Austria)); Gomez, I. (Nuklearmedizinische Abt., LKH Klagenfurt (Austria)); Gallowitsch, H.J. (Nuklearmedizinische Abt., LKH Klagenfurt (Austria)); Lind, P. (Nuklearmedizinische Abt., LKH Klagenfurt (Austria))

    1993-08-01

    In a retrospective study of 160 patients who were examined within 12 months, we analysed the diagnosic value of scintigraphic techniques in the differential diagnosis of solid focal liver lesions. Haemangiomas were found in 77 patients. Bloodpool scintigraphy was true-positive in 66 (sensivitity 85%); for lesions greater than 2 cm in diameter, sensitivity increased to 94%. Metastases of CEA-expressing tumors were found in 42 patients, anti-CEA-immunoscintigraphy was true-positive in 33 patients (sensitivity 78.5%). Focal nodulary hyperplasia was found in 3 patients, adenomas in 6 patients. In the remaining 32 patiens we saw 4 hepatocellular carcinomas, 28 metastases from lung and breast cancer, 2 echinococcus cysts and 1 choledochus cyst. (orig.)

  10. 99mTc-ceftriaxone, as a targeting radiopharmaceutical for scintigraphic imaging of infectious foci due to Staphylococcus aureus in mouse model

    International Nuclear Information System (INIS)

    Akram Fazli; Mojtaba Salouti; Mohammad Mazidi

    2013-01-01

    99m Tc-labeled antibiotics have opened an exciting field of research in infectious diseases diagnosis. Direct labeling of ceftriaxone with 99mTc was carried out using the various amounts of ceftriaxone and SnCl 2 ·2H 2 O at different pH and incubation time intervals to find the highest radiochemistry efficiency with high stability at room temperature and human blood serum. ITLC-SG and HPLC were performed to measure the radiochemical purity of the conjugate. The binding study showed 45 % specific binding to Staphylococcus aureus. The biodistribution study and scintigraphic imaging showed the localization of 99m Tc-ceftriaxone at the site of infection in comparison with normal and inflamed muscles with high sensitivity and specificity in mouse model. The results showed that 99m Tc-ceftriaxone is a promising candidate as a targeting radiopharmaceutical for Staphylococcal infection imaging in humans which needs further investigations. (author)

  11. In vitro radionuclide therapy and in vivo scintigraphic imaging of alpha fetoprotein producing hepatocellular carcinoma by targeted sodium iodide symporter gene expression

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kwang Il; Lee, Yong Jin; Lee, Tae Sup; Song, Inho; Cheon, Gi Jeong; Lim, Sang Moo; Kang, Joo Hyun [Korea Institute of Radiological and Medical and Medical Sciences, Seoul (Korea, Republic of); Chung, June Key [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of)

    2012-03-15

    This study aimed to develop a gene expression targeting method for specific imaging and therapy of alpha fetoprotein (AFP) producing hepatocellular carcinoma (HCC) cells, using an adenovirus vector containing the human sodium/iodide symporter (hNIS) gene driven by an AFP enhancer/promoter. The recombinant adenovirus vector, AdAFPhNIS (containing the hNIS gene driven by human AFP enhancer/promoter) was prepared. After in vitro infection by the adenovirus, hNIS gene expression in AFP producing cells and in AFP nonproducing cells was investigated using {sup 125}I uptake assay and semi quantitative reverse transcription polymerase chain reaction (RT-PCR). The killing effect of {sup 131}I vitro clonogenic assay. In addition, tumor bearing mice were intravenously injected with the adenovirus, and scintigraphic images were obtained. The expression of hNIS was efficiently demonstrated by {sup 125}I uptake assay in AFP producing cells, but not in AFP nonproducing cells. AFP producing HCC targeted gene expression was confirmed at the mRNA level. Furthermore, in vitro clonogenic assay showed that hNIS gene expression induced by AdAFPhNIS infection in AFP producing cells caused more sensitivity to {sup 131}I than that in AFP nonproducing cells. Injected intravenously in HuH-7 tumor xenografts mice by adenovirus, the functional hNIS gene expression was confirmed in tumor by in vivo scintigraphic imaging. An AFP producing HCC was targeted with an adenovirus vector containing the hNIS gene using the AFP enhancer/promoter in vitro and in vivo. These findings demonstrate that AFP producing HCC specific molecular imaging and radionuclide gene therapy are feasible using this recombinant adenovirus vector system.

  12. In vitro radionuclide therapy and in vivo scintigraphic imaging of alpha fetoprotein producing hepatocellular carcinoma by targeted sodium iodide symporter gene expression

    International Nuclear Information System (INIS)

    Kim, Kwang Il; Lee, Yong Jin; Lee, Tae Sup; Song, Inho; Cheon, Gi Jeong; Lim, Sang Moo; Kang, Joo Hyun; Chung, June Key

    2012-01-01

    This study aimed to develop a gene expression targeting method for specific imaging and therapy of alpha fetoprotein (AFP) producing hepatocellular carcinoma (HCC) cells, using an adenovirus vector containing the human sodium/iodide symporter (hNIS) gene driven by an AFP enhancer/promoter. The recombinant adenovirus vector, AdAFPhNIS (containing the hNIS gene driven by human AFP enhancer/promoter) was prepared. After in vitro infection by the adenovirus, hNIS gene expression in AFP producing cells and in AFP nonproducing cells was investigated using 125 I uptake assay and semi quantitative reverse transcription polymerase chain reaction (RT-PCR). The killing effect of 131 I vitro clonogenic assay. In addition, tumor bearing mice were intravenously injected with the adenovirus, and scintigraphic images were obtained. The expression of hNIS was efficiently demonstrated by 125 I uptake assay in AFP producing cells, but not in AFP nonproducing cells. AFP producing HCC targeted gene expression was confirmed at the mRNA level. Furthermore, in vitro clonogenic assay showed that hNIS gene expression induced by AdAFPhNIS infection in AFP producing cells caused more sensitivity to 131 I than that in AFP nonproducing cells. Injected intravenously in HuH-7 tumor xenografts mice by adenovirus, the functional hNIS gene expression was confirmed in tumor by in vivo scintigraphic imaging. An AFP producing HCC was targeted with an adenovirus vector containing the hNIS gene using the AFP enhancer/promoter in vitro and in vivo. These findings demonstrate that AFP producing HCC specific molecular imaging and radionuclide gene therapy are feasible using this recombinant adenovirus vector system

  13. Identification of Biokinetic Models Using the Concept of Extents.

    Science.gov (United States)

    Mašić, Alma; Srinivasan, Sriniketh; Billeter, Julien; Bonvin, Dominique; Villez, Kris

    2017-07-05

    The development of a wide array of process technologies to enable the shift from conventional biological wastewater treatment processes to resource recovery systems is matched by an increasing demand for predictive capabilities. Mathematical models are excellent tools to meet this demand. However, obtaining reliable and fit-for-purpose models remains a cumbersome task due to the inherent complexity of biological wastewater treatment processes. In this work, we present a first study in the context of environmental biotechnology that adopts and explores the use of extents as a way to simplify and streamline the dynamic process modeling task. In addition, the extent-based modeling strategy is enhanced by optimal accounting for nonlinear algebraic equilibria and nonlinear measurement equations. Finally, a thorough discussion of our results explains the benefits of extent-based modeling and its potential to turn environmental process modeling into a highly automated task.

  14. Extent, accuracy, and credibility of breastfeeding information on the Internet.

    Science.gov (United States)

    Shaikh, Ulfat; Scott, Barbara J

    2005-05-01

    Our objective was to test and describe a model for evaluating Websites related to breastfeeding. Forty Websites most likely to be accessed by the public were evaluated for extent, accuracy, credibility, presentation, ease of use, and adherence to ethical and medical Internet publishing standards. Extent and accuracy of Website content were determined by a checklist of critical information. The majority of Websites reviewed provided accurate information and complied with the International Code of Marketing of Breast-milk Substitutes. Approximately half the Websites complied with standards of medical Internet publishing. While much information on breastfeeding on the Internet is accurate, there is wide variability in the extent of information, usability of Websites, and compliance with standards of medical Internet publishing. Results of this study may be helpful to health care professionals as a model for evaluating breastfeeding-related Websites and to highlight considerations when recommending or designing Websites.

  15. Extent of linkage disequilibrium in the domestic cat, Felis silvestris catus, and its breeds.

    Directory of Open Access Journals (Sweden)

    Hasan Alhaddad

    Full Text Available Domestic cats have a unique breeding history and can be used as models for human hereditary and infectious diseases. In the current era of genome-wide association studies, insights regarding linkage disequilibrium (LD are essential for efficient association studies. The objective of this study is to investigate the extent of LD in the domestic cat, Felis silvestris catus, particularly within its breeds. A custom illumina GoldenGate Assay consisting of 1536 single nucleotide polymorphisms (SNPs equally divided over ten 1 Mb chromosomal regions was developed, and genotyped across 18 globally recognized cat breeds and two distinct random bred populations. The pair-wise LD descriptive measure (r(2 was calculated between the SNPs in each region and within each population independently. LD decay was estimated by determining the non-linear least-squares of all pair-wise estimates as a function of distance using established models. The point of 50% decay of r(2 was used to compare the extent of LD between breeds. The longest extent of LD was observed in the Burmese breed, where the distance at which r(2 ≈ 0.25 was ∼380 kb, comparable to several horse and dog breeds. The shortest extent of LD was found in the Siberian breed, with an r(2 ≈ 0.25 at approximately 17 kb, comparable to random bred cats and human populations. A comprehensive haplotype analysis was also conducted. The haplotype structure of each region within each breed mirrored the LD estimates. The LD of cat breeds largely reflects the breeds' population history and breeding strategies. Understanding LD in diverse populations will contribute to an efficient use of the newly developed SNP array for the cat in the design of genome-wide association studies, as well as to the interpretation of results for the fine mapping of disease and phenotypic traits.

  16. Efficacy of helical CT in evaluating local tumor extent of breast cancer

    International Nuclear Information System (INIS)

    Ozaki, Yutaka

    2001-01-01

    The purpose of this study is to clarify the diagnostic accuracy of helical CT (HCT) in the determination of local tumor extent of breast cancer. One hundred forty consecutive patients with breast cancer, including 87 invasive ductal carcinomas without extensive intraductal components (EIC), 44 invasive ductal carcinomas with EIC, 2 non-invasive ductal carcinomas, and 7 invasive lobular carcinomas, were included in the study. Three-dimensional tumor diameter including whole extent was measured on HCT, and the amount of invasion to fat tissue, skin, pectoral muscle, and chest wall was estimated using a three-step scale. These results were then compared with the pathological findings. Breast cancers appeared as areas of high attenuation compared with the surrounding breast tissue in all patients. Tumor extent was correctly diagnosed by HCT to within a maximum difference of 1 cm in 88 patients (63%) and within 2 cm in 122 patients (87%). Sensitivity, specificity, and accuracy in diagnosing muscular invasion of breast cancer using HCT were 100%, 99%, and 99%, respectively. Sensitivity, specificity, and accuracy in diagnosing skin invasion of breast cancer using HCT were 84%, 93%, and 91%, respectively. HCT was able to visualize all of the tumors and detect the correct tumor extent in most patients. (author)

  17. Efficacy of helical CT in evaluating local tumor extent of breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Ozaki, Yutaka [Juntendo Univ., Chiba (Japan). Urayasu Hospital

    2001-04-01

    The purpose of this study is to clarify the diagnostic accuracy of helical CT (HCT) in the determination of local tumor extent of breast cancer. One hundred forty consecutive patients with breast cancer, including 87 invasive ductal carcinomas without extensive intraductal components (EIC), 44 invasive ductal carcinomas with EIC, 2 non-invasive ductal carcinomas, and 7 invasive lobular carcinomas, were included in the study. Three-dimensional tumor diameter including whole extent was measured on HCT, and the amount of invasion to fat tissue, skin, pectoral muscle, and chest wall was estimated using a three-step scale. These results were then compared with the pathological findings. Breast cancers appeared as areas of high attenuation compared with the surrounding breast tissue in all patients. Tumor extent was correctly diagnosed by HCT to within a maximum difference of 1 cm in 88 patients (63%) and within 2 cm in 122 patients (87%). Sensitivity, specificity, and accuracy in diagnosing muscular invasion of breast cancer using HCT were 100%, 99%, and 99%, respectively. Sensitivity, specificity, and accuracy in diagnosing skin invasion of breast cancer using HCT were 84%, 93%, and 91%, respectively. HCT was able to visualize all of the tumors and detect the correct tumor extent in most patients. (author)

  18. LEVEL AND EXTENT OF MERCURY CONTAMINATION IN OREGON LOTIC FISH

    Science.gov (United States)

    As part of the U.S. EPA's EMAP Oregon Pilot project, we conducted a probability survey of 154 Oregon streams and rivers to assess the spatial extent of mercury (Hg) contamination in fish tissue across the state. Samples consisted of whole fish analyses of both small (< 120 mm) a...

  19. Spatial extent in demographic research - approach and problems

    Directory of Open Access Journals (Sweden)

    Knežević Aleksandar

    2015-01-01

    Full Text Available One of the starting methodological problems in demographic research is the definition of spatial extent, which mostly doesn’t correspond to spatial extent already defined by different levels of administrative-territorial unitsthat are used for distribution of usable statistical data. That’s why determining the spatial extent of a demographic research is closely tied with administrative-territorial division of the territory that is being researched, wherein the fact that differentiation of demographic phenomena and processes cannot be the only basis of setting the principles of regionalization must be strictly acknowledged. This problem is particularly common in historical demographic analyses of geographically determined wholes, which are in administratively-territorial sense represented by one or more smaller territorial units, with their borders changing through the history, which directly affects comparability of the statistical data, and makes it considerably more difficult to track demographic change through longer time intervals. The result of these efforts is usually a solution based on a compromise which enables us to examine the dynamics of population change with little deviation from already defined borders of regional geographic wholes. For that reason in this paper the problem of defining spatial extent in demographic research is examined trough several different approaches in case of Eastern Serbia, as a geographically determined region, a historic area, a spatially functioning whole and as a statistical unit for demographic research, with no judgment calls in regard to any of the regionalization principles. [Projekat Ministarstva nauke Republike Srbije, br. III 47006

  20. Does Trust Influence the Extent of Inter-Organizational Barter?

    DEFF Research Database (Denmark)

    Sudzina, Frantisek

    2014-01-01

    The 1999 World Business Environment Survey investigated, among many other things, the extent of inter-organizational barter in various countries. Reported values differed a lot, e.g. it was less than 1% in Hungary but more than 30% in neighboring Croatia. Since in many such contracts goods and...

  1. Veterinary drug prescriptions: to what extent do pet owners comply ...

    African Journals Online (AJOL)

    Separate questionnaires were designed for pet owners (clients) and veterinarians to ascertain the existence and extent of noncompliance in veterinary practice in lbadan and to elucidate the influence of such factors as logistics, education, economy, attitudes and veterinarian/client relationship on non-compliance. Analyses ...

  2. To what extent does banks' credit stimulate economic growth ...

    African Journals Online (AJOL)

    This study examines the extent to which banks' credit affects economic growth in Nigeria. The data used was collected from the Central Bank of Nigeria statistical bulletin for a period of 24 years from 1990 to 2013. We used credit to the private sector, credit to the public sector and inflation to proxy commercial bank credit ...

  3. Extent of reaction in open systems with multiple heterogeneous reactions

    Science.gov (United States)

    Friedly, John C.

    1991-01-01

    The familiar batch concept of extent of reaction is reexamined for systems of reactions occurring in open systems. Because species concentrations change as a result of transport processes as well as reactions in open systems, the extent of reaction has been less useful in practice in these applications. It is shown that by defining the extent of the equivalent batch reaction and a second contribution to the extent of reaction due to the transport processes, it is possible to treat the description of the dynamics of flow through porous media accompanied by many chemical reactions in a uniform, concise manner. This approach tends to isolate the reaction terms among themselves and away from the model partial differential equations, thereby enabling treatment of large problems involving both equilibrium and kinetically controlled reactions. Implications on the number of coupled partial differential equations necessary to be solved and on numerical algorithms for solving such problems are discussed. Examples provided illustrate the theory applied to solute transport in groundwater flow.

  4. Extent and Distribution of Groundwater Resources in Parts of ...

    African Journals Online (AJOL)

    The extent and distribution of groundwater resources in parts of Anambra State, Nigeria has been investigated. The results show that the study area is directly underlain by four different geological formations including, Alluvial Plain Sands, Ogwashi-Asaba Formation, Ameki/Nanka Sands and Imo Shale, with varying water ...

  5. Extent of implementation of collection development policies in ...

    African Journals Online (AJOL)

    The study is a survey research on the extent of implementation of collection development policies in academic libraries in Imo state. The population of the study comprises five (5) academic libraries in the area of study. The academic libraries understudy are: Imo State University Owerri (IMSU), Federal University of ...

  6. An investigation into Nigerian teacher's attitude towards and extent ...

    African Journals Online (AJOL)

    The attitude of Biology teachers towards and their extent of improvisation, were investigated 80 teachers from 50 randomly selected secondary schools in Oyo state of Nigeria participated in the study. Analysis of the twenty item questionnaire administered to the teachers revealed that though many of them exhibited positive ...

  7. Extent of implementation of Collection Development Policies (CDP ...

    African Journals Online (AJOL)

    The study was on the extent of implementation of collection development policies by public University libraries in the Niger Delta Area, Nigeria. Descriptive survey design was employed. Population for the study consisted of all the 16 Colle ction Development Librarians in the Area studied. No sample was used because the ...

  8. The extent of groundwater use for domestic and irrigation activities ...

    African Journals Online (AJOL)

    AKMENSAH

    2015-06-04

    Jun 4, 2015 ... Albert Kobina Mensah1*, Evans Appiah Kissi2, Kwabena Krah3 and Okoree D. Mireku4. 1Department of Geography, Kenyatta University, Nairobi. 2Department of .... catchment in Kiambu County in Kenya had limited themselves to the assessment of water quality. Little work has been done on the extent to ...

  9. The Extent of Reversibility of Polychlorinated Biphenyl Adsorption

    Science.gov (United States)

    The extent of reversibility of PCB bonding to sediments has been characterized in studies on the partitioning behavior of a hexachlorobiphenyl isomer. Linear non-singular isotherms have been observed for the adsorption and desorption of 2.4.5.2?,4?,5? hexachlorobiphenyl (HCBP) to...

  10. The Extent of Educational Technology's Influence on Contemporary Educational Practices

    OpenAIRE

    Kim, Bradford-Watts

    2005-01-01

    This paper investigates how advances in educational technologies have influenced contemporary educational practices.It discusses the nature of educational technology, the limitations imposed by the digital divide and other factors of uptake, and the factors leading to successful implementation of educational technologies.The extent of influence is then discussed,together with the probable implications for educational sites for the future.

  11. Determining wetland spatial extent and seasonal variations of the ...

    African Journals Online (AJOL)

    This study, done in the Witbank Dam Catchment in Mpumalanga Province of South Africa, explores a remote-sensing technique to delineate wetland extent and assesses the seasonal variations of the inundated area. The objective was to monitor the spatio-temporal changes of wetlands over time through remote sensing ...

  12. 32 CFR 728.12 - Extent of care.

    Science.gov (United States)

    2010-07-01

    ... § 728.12 Extent of care. Members who are away from their duty stations or are on duty where there is no... providing authorization for non-Federal care at DHHS expense. (b) Maternity episode for active duty female... facilities (once the mother has been admitted to the USMTF) from funds available for care of active duty...

  13. 27 CFR 24.158 - Extent of relief.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Extent of relief. 24.158 Section 24.158 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT..., until all tax is fully paid. (d) Wine vinegar plant bond. The surety will be relieved of liability for...

  14. Automated flood extent identification using WorldView imagery for the insurance industry

    Science.gov (United States)

    Geller, Christina

    2017-10-01

    Flooding is the most common and costly natural disaster around the world, causing the loss of human life and billions in economic and insured losses each year. In 2016, pluvial and fluvial floods caused an estimated 5.69 billion USD in losses worldwide with the most severe events occurring in Germany, France, China, and the United States. While catastrophe modeling has begun to help bridge the knowledge gap about the risk of fluvial flooding, understanding the extent of a flood - pluvial and fluvial - in near real-time allows insurance companies around the world to quantify the loss of property that their clients face during a flooding event and proactively respond. To develop this real-time, global analysis of flooded areas and the associated losses, a new methodology utilizing optical multi-spectral imagery from DigitalGlobe (DGI) WorldView satellite suite is proposed for the extraction of pluvial and fluvial flood extents. This methodology involves identifying flooded areas visible to the sensor, filling in the gaps left by the built environment (i.e. buildings, trees) with a nearest neighbor calculation, and comparing the footprint against an Industry Exposure Database (IE) to calculate a loss estimate. Full-automation of the methodology allows production of flood extents and associated losses anywhere around the world as required. The methodology has been tested and proven effective for the 2016 flood in Louisiana, USA.

  15. SPECT imaging in evaluating extent of malignant external otitis: case report

    International Nuclear Information System (INIS)

    English, R.J.; Tu'Meh, S.S.; Piwnica-Worms, D.; Holman, B.L.

    1987-01-01

    Otitis externa, a benign inflammatory process of the external auditory canal, is general responsive to local therapy. Some patients however, develop a less controllable disease leading to chondritis and osteomyelitis of the base of the skull. The direct invasive characteristic of the disease has led to the descriptive term malignant external otitis (MEO), more appropriately called necrotizing or invasive external otitis. Malignant external otitis is caused by an aggressive pseudomonas or proteus infection that almost exclusively occurs in elderly diabetic patients. The primary imaging modalities previously used in the diagnosis and evaluation of MEO were standard planar scintigraphic techniques with technetium-99M (/sup 99m/Tc) bone agents and gallium-67 ( 67 Ga), and pluridirectional tomography. The advent of high resolution computed tomography (CT) effectively allowed demonstration of the soft tissue extension and bone destruction associated with MEO, but still suffered from the low sensitivity constraints of all radiographic techniques in determining early inflammatory bone involvement. Recent work suggests that scintigraphic detection of MEO with /sup 99m/Tc-MDP and 67 Ga, combined with the cross-sectional resolution of single photon emission computed tomography (SPECT) may be of value in planning treatment of this inflammatory condition

  16. Automated Snow Extent Mapping Based on Orthophoto Images from Unmanned Aerial Vehicles

    Science.gov (United States)

    Niedzielski, Tomasz; Spallek, Waldemar; Witek-Kasprzak, Matylda

    2018-04-01

    The paper presents the application of the k-means clustering in the process of automated snow extent mapping using orthophoto images generated using the Structure-from-Motion (SfM) algorithm from oblique aerial photographs taken by unmanned aerial vehicle (UAV). A simple classification approach has been implemented to discriminate between snow-free and snow-covered terrain. The procedure uses the k-means clustering and classifies orthophoto images based on the three-dimensional space of red-green-blue (RGB) or near-infrared-red-green (NIRRG) or near-infrared-green-blue (NIRGB) bands. To test the method, several field experiments have been carried out, both in situations when snow cover was continuous and when it was patchy. The experiments have been conducted using three fixed-wing UAVs (swinglet CAM by senseFly, eBee by senseFly, and Birdie by FlyTech UAV) on 10/04/2015, 23/03/2016, and 16/03/2017 within three test sites in the Izerskie Mountains in southwestern Poland. The resulting snow extent maps, produced automatically using the classification method, have been validated against real snow extents delineated through a visual analysis and interpretation offered by human analysts. For the simplest classification setup, which assumes two classes in the k-means clustering, the extent of snow patches was estimated accurately, with areal underestimation of 4.6% (RGB) and overestimation of 5.5% (NIRGB). For continuous snow cover with sparse discontinuities at places where trees or bushes protruded from snow, the agreement between automatically produced snow extent maps and observations was better, i.e. 1.5% (underestimation with RGB) and 0.7-0.9% (overestimation, either with RGB or with NIRRG). Shadows on snow were found to be mainly responsible for the misclassification.

  17. The extent of emphysema in patients with COPD

    DEFF Research Database (Denmark)

    Shaker, Saher Burhan; Stavngaard, Trine; Hestad, Marianne

    2009-01-01

    BACKGROUND AND AIMS: The global initiative for COPD (GOLD) adopted the degree of airway obstruction as a measure of the severity of the disease. The objective of this study was to apply CT to assess the extent of emphysema in patients with chronic obstructive pulmonary disease (COPD) and relate...... measurement and visual and quantitative assessment of CT, from which the relative area of emphysema below -910 Hounsfield units (RA-910) was extracted. RESULTS: Mean RA-910 was 7.4% (n = 5) in patients with GOLD stage I, 17.0% (n = 119) in stage II, 24.2% (n = 79) in stage III and 33.9% (n = 6) in stage IV....... Regression analysis showed a change in RA-910 of 7.8% with increasing severity according to GOLD stage (P emphysema, whereas 25 patients had no emphysema. CONCLUSION: The extent of emphysema...

  18. Extent of hippocampal atrophy predicts degree of deficit in recall.

    Science.gov (United States)

    Patai, Eva Zita; Gadian, David G; Cooper, Janine M; Dzieciol, Anna M; Mishkin, Mortimer; Vargha-Khadem, Faraneh

    2015-10-13

    Which specific memory functions are dependent on the hippocampus is still debated. The availability of a large cohort of patients who had sustained relatively selective hippocampal damage early in life enabled us to determine which type of mnemonic deficit showed a correlation with extent of hippocampal injury. We assessed our patient cohort on a test that provides measures of recognition and recall that are equated for difficulty and found that the patients' performance on the recall tests correlated significantly with their hippocampal volumes, whereas their performance on the equally difficult recognition tests did not and, indeed, was largely unaffected regardless of extent of hippocampal atrophy. The results provide new evidence in favor of the view that the hippocampus is essential for recall but not for recognition.

  19. A report on the extent of radioisotope usage in Malaysia

    International Nuclear Information System (INIS)

    1983-04-01

    A market survey was carried out to study the extent of radioisotope usage in Malaysia. From the survey, the radioisotopes and their activities/quantities that are used in Industry, Medicine and Research were identified. The radioisotopes that are frequently needed or routinely used were also determined and this formed the basis of the recommendations put forward in this report. It is proposed that PUSPATI adopt the concept of a Distribution Centre in order to provide a service to the Malaysian community. (author)

  20. The extent and impact of outsourcing: evidence from Germany

    OpenAIRE

    Craig P. Aubuchon; Subhayu Bandyopadhyay; Sumon Bhaumik

    2012-01-01

    The authors use data from several sources, including plant-level data from the manufacturing sector in Germany, to expand the literature on outsourcing. They find that, in Germany, the extent of outsourcing among manufacturing industries is higher than among service industries and that the outsourcing intensity of these industries did not change much between 1995 and 2005. They also find a statistically significantly positive impact of industry-level outsourcing intensity on German plant-leve...

  1. Statistics of Radial Ship Extent as Seen by a Seeker

    Science.gov (United States)

    2014-06-01

    Auckland in pure and applied mathematics and physics, and a Master of Science in physics from the same university with a thesis in applied accelerator...does not demand contributions from two angle bins to one extent bin, unlike the rectangle; this is a very big advantage of the ellipse model. However...waveform that mimics the full length of a ship. This allows more economical use to be made of available false-target generation resources. I wish to

  2. Regional Mapping of Plantation Extent Using Multisensor Imagery

    Science.gov (United States)

    Torbick, N.; Ledoux, L.; Hagen, S.; Salas, W.

    2016-12-01

    Industrial forest plantations are expanding rapidly across the tropics and monitoring extent is critical for understanding environmental and socioeconomic impacts. In this study, new, multisensor imagery were evaluated and integrated to extract the strengths of each sensor for mapping plantation extent at regional scales. Three distinctly different landscapes with multiple plantation types were chosen to consider scalability and transferability. These were Tanintharyi, Myanmar, West Kalimantan, Indonesia, and southern Ghana. Landsat-8 Operational Land Imager (OLI), Phased Array L-band Synthetic Aperture Radar-2 (PALSAR-2), and Sentinel-1A images were fused within a Classification and Regression Tree (CART) framework using random forest and high-resolution surveys. Multi-criteria evaluations showed both L-and C-band gamma nought γ° backscatter decibel (dB), Landsat reflectance ρλ, and texture indices were useful for distinguishing oil palm and rubber plantations from other land types. The classification approach identified 750,822 ha or 23% of the Taninathryi, Myanmar, and 216,086 ha or 25% of western West Kalimantan as plantation with very high cross validation accuracy. The mapping approach was scalable and transferred well across the different geographies and plantation types. As archives for Sentinel-1, Landsat-8, and PALSAR-2 continue to grow, mapping plantation extent and dynamics at moderate resolution over large regions should be feasible.

  3. Exploring the Origin, Extent, and Future of Life

    Science.gov (United States)

    Bertka, Constance M.

    2009-09-01

    1. Astrobiology in societal context Constance Bertka; Part I. Origin of Life: 2. Emergence and the experimental pursuit of the origin of life Robert Hazen; 3. From Aristotle to Darwin, to Freeman Dyson: changing definitions of life viewed in historical context James Strick; 4. Philosophical aspects of the origin-of-life problem: the emergence of life and the nature of science Iris Fry; 5. The origin of terrestrial life: a Christian perspective Ernan McMullin; 6. The alpha and the omega: reflections on the origin and future of life from the perspective of Christian theology and ethics Celia Deane-Drummond; Part II. Extent of Life: 7. A biologist's guide to the Solar System Lynn Rothschild; 8. The quest for habitable worlds and life beyond the Solar System Carl Pilcher; 9. A historical perspective on the extent and search for life Steven J. Dick; 10. The search for extraterrestrial life: epistemology, ethics, and worldviews Mark Lupisella; 11. The implications of discovering extraterrestrial life: different searches, different issues Margaret S. Race; 12. God, evolution, and astrobiology Cynthia S. W. Crysdale; Part III. Future of Life: 13. Planetary ecosynthesis on Mars: restoration ecology and environmental ethics Christopher P. McKay; 14. The trouble with intrinsic value: an ethical primer for astrobiology Kelly C. Smith; 15. God's preferential option for life: a Christian perspective on astrobiology Richard O. Randolph; 16. Comparing stories about the origin, extent, and future of life: an Asian religious perspective Francisca Cho; Index.

  4. Monitoring the Extent of Forests on National to Global Scales

    Science.gov (United States)

    Townshend, J.; Townshend, J.; Hansen, M.; DeFries, R.; DeFries, R.; Sohlberg, R.; Desch, A.; White, B.

    2001-05-01

    Information on forest extent and change is important for many purposes, including understanding the global carbon cycle and managing natural resources. International statistics on forest extent are generated using many different sources often producing inconsistent results spatially and through time. Results will be presented comparing forest extent derived from the recent global Food and Agricultural Organization's (FAO) FRA 2000 report with products derived using wall-to-wall Landsat, AVHRR and MODIS data sets. The remotely sensed data sets provide consistent results in terms of total area despite considerable differences in spatial resolution. Although the location of change can be satisfactorily detected with all three remotely sensed data sets, reliable measurement of change can only be achieved through use of Landsat-resolution data. Contrary to the FRA 2000 results we find evidence of an increase in deforestation rates in the late 1990s in several countries. Also we have found evidence of considerable changes in some countries for which little or no change is reported by FAO. The results indicate the benefits of globally consistent analyses of forest cover based on multiscale remotely sensed data sets rather than a reliance on statistics generated by individual countries with very different definitions of forest and methods used to derive them.

  5. The extent of emphysema in patients with COPD.

    Science.gov (United States)

    Shaker, Saher Burhan; Stavngaard, Trine; Hestad, Marianne; Bach, Karen Skjoelstrup; Tonnesen, Philip; Dirksen, Asger

    2009-01-01

    The global initiative for COPD (GOLD) adopted the degree of airway obstruction as a measure of the severity of the disease. The objective of this study was to apply CT to assess the extent of emphysema in patients with chronic obstructive pulmonary disease (COPD) and relate this extent to the GOLD stage of airway obstruction. We included 209 patients with COPD. COPD was defined as FEV(1)/FVC or=20 pack-years. Patients were assessed by lung function measurement and visual and quantitative assessment of CT, from which the relative area of emphysema below -910 Hounsfield units (RA-910) was extracted. Mean RA-910 was 7.4% (n = 5) in patients with GOLD stage I, 17.0% (n = 119) in stage II, 24.2% (n = 79) in stage III and 33.9% (n = 6) in stage IV. Regression analysis showed a change in RA-910 of 7.8% with increasing severity according to GOLD stage (P < 0.001). Combined visual and quantitative assessment of CT showed that 184 patients had radiological evidence of emphysema, whereas 25 patients had no emphysema. The extent of emphysema increases with increasing severity of COPD and most patients with COPD have emphysema. Tissue destruction by emphysema is therefore an important determinant of disease severity in COPD.

  6. LGM permafrost thickness and extent in the Northern Hemisphere derived from the earth system model iLOVECLIM

    NARCIS (Netherlands)

    Kitover, D.C.; van Balen, R.T.; Vandenberghe, J.F.; Roche, D.M.V.A.P.; Renssen, H.

    2016-01-01

    An estimate of permafrost extent and thickness in the northern hemisphere during the Last Glacial Maximum (LGM, ~ 21 ka) has been produced using the VU University Amsterdam Permafrost Snow (VAMPERS) model, forced by iLOVECLIM, an Earth System Model of Intermediate Complexity. We present model

  7. A Global Geospatial Database of 5000+ Historic Flood Event Extents

    Science.gov (United States)

    Tellman, B.; Sullivan, J.; Doyle, C.; Kettner, A.; Brakenridge, G. R.; Erickson, T.; Slayback, D. A.

    2017-12-01

    A key dataset that is missing for global flood model validation and understanding historic spatial flood vulnerability is a global historical geo-database of flood event extents. Decades of earth observing satellites and cloud computing now make it possible to not only detect floods in near real time, but to run these water detection algorithms back in time to capture the spatial extent of large numbers of specific events. This talk will show results from the largest global historical flood database developed to date. We use the Dartmouth Flood Observatory flood catalogue to map over 5000 floods (from 1985-2017) using MODIS, Landsat, and Sentinel-1 Satellites. All events are available for public download via the Earth Engine Catalogue and via a website that allows the user to query floods by area or date, assess population exposure trends over time, and download flood extents in geospatial format.In this talk, we will highlight major trends in global flood exposure per continent, land use type, and eco-region. We will also make suggestions how to use this dataset in conjunction with other global sets to i) validate global flood models, ii) assess the potential role of climatic change in flood exposure iii) understand how urbanization and other land change processes may influence spatial flood exposure iv) assess how innovative flood interventions (e.g. wetland restoration) influence flood patterns v) control for event magnitude to assess the role of social vulnerability and damage assessment vi) aid in rapid probabilistic risk assessment to enable microinsurance markets. Authors on this paper are already using the database for the later three applications and will show examples of wetland intervention analysis in Argentina, social vulnerability analysis in the USA, and micro insurance in India.

  8. Extent of pyrolysis impacts on fast pyrolysis biochar properties.

    Science.gov (United States)

    Brewer, Catherine E; Hu, Yan-Yan; Schmidt-Rohr, Klaus; Loynachan, Thomas E; Laird, David A; Brown, Robert C

    2012-01-01

    A potential concern about the use of fast pyrolysis rather than slow pyrolysis biochars as soil amendments is that they may contain high levels of bioavailable C due to short particle residence times in the reactors, which could reduce the stability of biochar C and cause nutrient immobilization in soils. To investigate this concern, three corn ( L.) stover fast pyrolysis biochars prepared using different reactor conditions were chemically and physically characterized to determine their extent of pyrolysis. These biochars were also incubated in soil to assess their impact on soil CO emissions, nutrient availability, microorganism population growth, and water retention capacity. Elemental analysis and quantitative solid-state C nuclear magnetic resonance spectroscopy showed variation in O functional groups (associated primarily with carbohydrates) and aromatic C, which could be used to define extent of pyrolysis. A 24-wk incubation performed using a sandy soil amended with 0.5 wt% of corn stover biochar showed a small but significant decrease in soil CO emissions and a decrease in the bacteria:fungi ratios with extent of pyrolysis. Relative to the control soil, biochar-amended soils had small increases in CO emissions and extractable nutrients, but similar microorganism populations, extractable NO levels, and water retention capacities. Corn stover amendments, by contrast, significantly increased soil CO emissions and microbial populations, and reduced extractable NO. These results indicate that C in fast pyrolysis biochar is stable in soil environments and will not appreciably contribute to nutrient immobilization. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  9. Detecting the Extent of Eutectoid Transformation in U-10Mo

    Energy Technology Data Exchange (ETDEWEB)

    Devaraj, Arun [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jana, Saumyadeep [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); McInnis, Colleen A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lombardo, Nicholas J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Joshi, Vineet V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Sweet, Lucas E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Manandhar, Sandeep [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lavender, Curt A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-08-31

    During eutectoid transformation of U-10Mo alloy, uniform metastable γ UMo phase is expected to transform to a mixture of α-U and γ’-U2Mo phase. The presence of transformation products in final U-10Mo fuel, especially the α phase is considered detrimental for fuel irradiation performance, so it is critical to accurately evaluate the extent of transformation in the final U-10Mo alloy. This phase transformation can cause a volume change that induces a density change in final alloy. To understand this density and volume change, we developed a theoretical model to calculate the volume expansion and resultant density change of U-10Mo alloy as a function of the extent of eutectoid transformation. Based on the theoretically calculated density change for 0 to 100% transformation, we conclude that an experimental density measurement system will be challenging to employ to reliably detect and quantify the extent of transformation. Subsequently, to assess the ability of various methods to detect the transformation in U-10Mo, we annealed U-10Mo alloy samples at 500°C for various times to achieve in low, medium, and high extent of transformation. After the heat treatment at 500°C, the samples were metallographically polished and subjected to optical microscopy and x-ray diffraction (XRD) methods. Based on our assessment, optical microscopy and image processing can be used to determine the transformed area fraction, which can then be correlated with the α phase volume fraction measured by XRD analysis. XRD analysis of U-10Mo aged at 500°C detected only α phase and no γ’ was detected. To further validate the XRD results, atom probe tomography (APT) was used to understand the composition of transformed regions in U-10Mo alloys aged at 500°C for 10 hours. Based on the APT results, the lamellar transformation product was found to comprise α phase with close to 0 at% Mo and γ phase with 28–32 at% Mo, and the Mo concentration was highest at the

  10. Extent of the Immirzi ambiguity in quantum general relativity

    International Nuclear Information System (INIS)

    Marugan, Guillermo A Mena

    2002-01-01

    The Ashtekar-Barbero formulation of general relativity admits a one-parameter family of canonical transformations that preserves the expressions of the Gauss and diffeomorphism constraints. The loop quantization of the connection formalism based on each of these canonical sets leads to different predictions. This phenomenon is called the Immirzi ambiguity. It has been recently argued that this ambiguity could be generalized to the extent of a spatially dependent function instead of a parameter. This would ruin the predictability of loop quantum gravity. We prove that such expectations are not realized, so that the Immirzi ambiguity introduces exclusively a freedom in the choice of a real number. (letter to the editor)

  11. Determination of extent of surgical intervention for endometrial carcinoma

    International Nuclear Information System (INIS)

    Smakhtina, O.L.; Nugmanova, M.I.; Nigaj, S.V.

    1986-01-01

    Clinical, cytologic, histologic and X-ray procedures were used in examining 120 patients with endometrial carcinoma. The results of pre- and intraoperative determination of clinical stage were compared in 65 cases of uterine extirpation with appendages and lymphadenectomy. Errors in preoperative identification of the extent of tumor expansion were made in 9 cases (13.8+-4.3%). It was found that determinations of the site and expansion of tumor make the case for hysterocervico-angiolymphography whereas identification of tumor pattern and degree of cell differentiation-for cytologic and histologic assays

  12. Detecting the Extent of Eutectoid Transformation in U-10Mo

    International Nuclear Information System (INIS)

    Devaraj, Arun; Jana, Saumyadeep; McInnis, Colleen A.; Lombardo, Nicholas J.; Joshi, Vineet V.; Sweet, Lucas E.; Manandhar, Sandeep; Lavender, Curt A.

    2016-01-01

    During eutectoid transformation of U-10Mo alloy, uniform metastable ? UMo phase is expected to transform to a mixture of ?-U and ?'-U_2Mo phase. The presence of transformation products in final U-10Mo fuel, especially the ? phase is considered detrimental for fuel irradiation performance, so it is critical to accurately evaluate the extent of transformation in the final U-10Mo alloy. This phase transformation can cause a volume change that induces a density change in final alloy. To understand this density and volume change, we developed a theoretical model to calculate the volume expansion and resultant density change of U-10Mo alloy as a function of the extent of eutectoid transformation. Based on the theoretically calculated density change for 0 to 100% transformation, we conclude that an experimental density measurement system will be challenging to employ to reliably detect and quantify the extent of transformation. Subsequently, to assess the ability of various methods to detect the transformation in U-10Mo, we annealed U-10Mo alloy samples at 500°C for various times to achieve in low, medium, and high extent of transformation. After the heat treatment at 500°C, the samples were metallographically polished and subjected to optical microscopy and x-ray diffraction (XRD) methods. Based on our assessment, optical microscopy and image processing can be used to determine the transformed area fraction, which can then be correlated with the ? phase volume fraction measured by XRD analysis. XRD analysis of U-10Mo aged at 500°C detected only ? phase and no ?' was detected. To further validate the XRD results, atom probe tomography (APT) was used to understand the composition of transformed regions in U-10Mo alloys aged at 500°C for 10 hours. Based on the APT results, the lamellar transformation product was found to comprise ? phase with close to 0 at% Mo and ? phase with 28-32 at% Mo, and the Mo concentration was highest at the ?/? interface.

  13. Measurement of extent of intense ion beam charge neutralization

    Energy Technology Data Exchange (ETDEWEB)

    Engelko, V [Efremov Institute of Electrophysical Apparatus, St. Petersburg (Russian Federation); Giese, H; Schalk, S [Forschungszentrum Karlsruhe (Germany). INR

    1997-12-31

    Various diagnostic tools were employed to study and optimize the extent of space charge neutralization in the pulsed intense proton beam facility PROFA, comprising Langmuir probes, capacitive probes, and a novel type of the three electrode collector. The latter does not only allow us to measure ion and electron beam current densities in a high magnetic field environment, but also to deduce the density spectrum of the beam electrons. Appropriate operating conditions were identified to attain a complete space charge neutralisation. (author). 5 figs., 4 refs.

  14. Extent and application of patient diaries in Austria

    DEFF Research Database (Denmark)

    Heindl, Patrik; Bachlechner, Adelbert; Nydahl, Peter

    2017-01-01

    Background: Diaries written for patients in the intensive care unit (ICU) are offered in many European countries. In Austria, ICU diaries have been relatively unknown, but since 2012, they have started to emerge. Aim: The aim of this study was to explore the extent and application of ICU diaries...... in Austria in 2015. Method: The study had a prospective multiple methods design of survey and interviews. All ICUs in Austria were surveyed in 2015 to identify which ICUs used diaries. ICUs using diaries were selected for semi-structured key-informant telephone interviews on the application of ICU diaries...

  15. A method for predicting the extent of petroleum hydrocarbon biodegradation in contaminated soils

    International Nuclear Information System (INIS)

    Huesemann, M.H.

    1994-01-01

    A series of solid- and slurry-phase soil bioremediation experiments involving different crude oils and refined petroleum products were performed to investigate the factors which affect the maximum extent of total petroleum hydrocarbon (TPH) biodegradation. The authors used a comprehensive petroleum hydrocarbon characterization procedure involving group-type separation analyses, boiling-point distributions, and hydrocarbon typing by field ionization mass spectroscopy. Initial and final concentrations of specified hydrocarbon classes were determined in each of seven different bioremediation treatments. Generally, they found that the degree of TPH biodegradation was affected mainly by the type of hydrocarbons in the contaminant matrix. In contrast, the influence of experimental variables such as soil type, fertilizer concentrations, microbial plate counts, and treatment type (slurry versus landfarming) on the overall extent of TPH biodegradation was insignificant. Based on these findings, a predictive algorithm was developed to estimate the extent of TPH biodegradation from the average reduction of 86 individual hydrocarbon classes and their respective initial concentrations. Model predictions for gravimetric TPH removals were in close agreement with analytical results from two independent laboratories

  16. Chromosphere of K giant stars. Geometrical extent and spatial structure detection

    Science.gov (United States)

    Berio, P.; Merle, T.; Thévenin, F.; Bonneau, D.; Mourard, D.; Chesneau, O.; Delaa, O.; Ligi, R.; Nardetto, N.; Perraut, K.; Pichon, B.; Stee, P.; Tallon-Bosc, I.; Clausse, J. M.; Spang, A.; McAlister, H.; ten Brummelaar, T.; Sturmann, J.; Sturmann, L.; Turner, N.; Farrington, C.; Goldfinger, P. J.

    2011-11-01

    Context. Interferometers provide accurate diameter measurements of stars by analyzing both the continuum and the lines formed in photospheres and chromospheres. Tests of the geometrical extent of the chromospheres are therefore possible by comparing the estimated radius in the continuum of the photosphere and the estimated radii in chromospheric lines. Aims: We aim to constrain the geometrical extent of the chromosphere of non-binary K giant stars and detect any spatial structures in the chromosphere. Methods: We performed observations with the CHARA interferometer and the VEGA beam combiner at optical wavelengths. We observed seven non-binary K giant stars (β and η Cet, δ Crt, ρ Boo, β Oph, 109 Her, and ι Cep). We measured the ratio of the radii of the photosphere to the chromosphere using the interferometric measurements in the Hα and the Ca II infrared triplet line cores. For β Cet, spectro-interferometric observations are compared to a non-local thermal equilibrium (NLTE) semi-empirical model atmosphere including a chromosphere. The NLTE computations provide line intensities and contribution functions that indicate the relative locations where the line cores are formed and can constrain the size of the limb-darkened disk of the stars with chromospheres. We measured the angular diameter of seven K giant stars and deduced their fundamental parameters: effective temperatures, radii, luminosities, and masses. We determined the geometrical extent of the chromosphere for four giant stars (β and η Cet, δ Crt and ρ Boo). Results: The chromosphere extents obtained range between 16% to 47% of the stellar radius. The NLTE computations confirm that the Ca II/849 nm line core is deeper in the chromosphere of β Cet than either of the Ca II/854 nm and Ca II/866 nm line cores. We present a modified version of a semi-empirical model atmosphere derived by fitting the Ca II triplet line cores of this star. In four of our targets, we also detect the signature of a

  17. TO WHAT EXTENT DOES THE DEGREE OF MEANINGFUL MODEL COMPLEXITY DEPEND ON OBSERVATION DATA?

    DEFF Research Database (Denmark)

    Brunner, Philip; Doherty, John; Christensen, Steen

    reduction of predictive uncertainty. This gives raise to interesting questions concerning the level of complexity required. The capacity of a recharge model to reduce the uncertainty of future groundwater level predictions does not rely on accurate estimation of all hydraulic properties affecting......We systematically quantify to what extent vadose zone parameters can be constrained by including different types of observation data in the calibration process. Observation data considered are hydraulic heads, soil saturation, evaporation and transpiration. Besides assessing parameter uncertainty....... The results show that observations of the hydraulic head allow a significant reduction of predictive uncertainty. However, this it is not because any parameter is well estimated. Rather, this reduction is acquired knowledge that is applicable to combinations of parameters that contribute to a significant...

  18. Reassessing the extent of the Q classification for containment paint

    International Nuclear Information System (INIS)

    Spires, G.

    1995-01-01

    A mounting number of site-specific paint debris transport and screen clogging analyses submitted to justify substandard containment paint work have been deemed persuasive by virtue of favorable U.S. Nuclear Regulatory Commission safety evaluation report (SER) findings. These lay a strong foundation for a standardized approach to redefining the extent to which paint in containment needs to be considered open-quotes Q.close quotes This information justifies an initiative by licensees to roll back paint work quality commitments made at the design phase. This paper questions the validity of the basic premise that all primary containment paint can significantly compromise core and containment cooling [emergency core cooling system/engineered safeguard feature (ECCS/ESF)]. It is posited that the physical extent of painted containment surfaces for which extant material qualification and quality control (QC) structures need apply can be limited to zones relatively proximate to ECCS/ESF suction points. For other painted containment surfaces, simplified criteria should be allowed

  19. The regional extent of suppression: strabismics versus nonstrabismics.

    Science.gov (United States)

    Babu, Raiju Jacob; Clavagnier, Simon R; Bobier, William; Thompson, Benjamin; Hess, Robert F

    2013-10-09

    Evidence is accumulating that suppression may be the cause of amblyopia rather than a secondary consequence of mismatched retinal images. For example, treatment interventions that target suppression may lead to better binocular and monocular outcomes. Furthermore, it has recently been demonstrated that the measurement of suppression may have prognostic value for patching therapy. For these reasons, the measurement of suppression in the clinic needs to be improved beyond the methods that are currently available, which provide a binary outcome. We describe a novel quantitative method for measuring the regional extent of suppression that is suitable for clinical use. The method involves a dichoptic perceptual matching procedure at multiple visual field locations. We compare a group of normal controls (mean age: 28 ± 5 years); a group with strabismic amblyopia (four with microesotropia, five with esotropia, and one with exotropia; mean age: 35 ± 10 years); and a group with nonstrabismic anisometropic amblyopia (mean age: 33 ± 12 years). The extent and magnitude of suppression was similar for observers with strabismic and nonstrabismic amblyopia. Suppression was strongest within the central field and extended throughout the 20° field that we measured. Suppression extends throughout the central visual field in both strabismic and anisometropic forms of amblyopia. The strongest suppression occurs within the region of the visual field corresponding to the fovea of the fixing eye.

  20. Corticocortical feedback increases the spatial extent of normalization.

    Science.gov (United States)

    Nassi, Jonathan J; Gómez-Laberge, Camille; Kreiman, Gabriel; Born, Richard T

    2014-01-01

    Normalization has been proposed as a canonical computation operating across different brain regions, sensory modalities, and species. It provides a good phenomenological description of non-linear response properties in primary visual cortex (V1), including the contrast response function and surround suppression. Despite its widespread application throughout the visual system, the underlying neural mechanisms remain largely unknown. We recently observed that corticocortical feedback contributes to surround suppression in V1, raising the possibility that feedback acts through normalization. To test this idea, we characterized area summation and contrast response properties in V1 with and without feedback from V2 and V3 in alert macaques and applied a standard normalization model to the data. Area summation properties were well explained by a form of divisive normalization, which computes the ratio between a neuron's driving input and the spatially integrated activity of a "normalization pool." Feedback inactivation reduced surround suppression by shrinking the spatial extent of the normalization pool. This effect was independent of the gain modulation thought to mediate the influence of contrast on area summation, which remained intact during feedback inactivation. Contrast sensitivity within the receptive field center was also unaffected by feedback inactivation, providing further evidence that feedback participates in normalization independent of the circuit mechanisms involved in modulating contrast gain and saturation. These results suggest that corticocortical feedback contributes to surround suppression by increasing the visuotopic extent of normalization and, via this mechanism, feedback can play a critical role in contextual information processing.

  1. Corticocortical feedback increases the spatial extent of normalization

    Science.gov (United States)

    Nassi, Jonathan J.; Gómez-Laberge, Camille; Kreiman, Gabriel; Born, Richard T.

    2014-01-01

    Normalization has been proposed as a canonical computation operating across different brain regions, sensory modalities, and species. It provides a good phenomenological description of non-linear response properties in primary visual cortex (V1), including the contrast response function and surround suppression. Despite its widespread application throughout the visual system, the underlying neural mechanisms remain largely unknown. We recently observed that corticocortical feedback contributes to surround suppression in V1, raising the possibility that feedback acts through normalization. To test this idea, we characterized area summation and contrast response properties in V1 with and without feedback from V2 and V3 in alert macaques and applied a standard normalization model to the data. Area summation properties were well explained by a form of divisive normalization, which computes the ratio between a neuron's driving input and the spatially integrated activity of a “normalization pool.” Feedback inactivation reduced surround suppression by shrinking the spatial extent of the normalization pool. This effect was independent of the gain modulation thought to mediate the influence of contrast on area summation, which remained intact during feedback inactivation. Contrast sensitivity within the receptive field center was also unaffected by feedback inactivation, providing further evidence that feedback participates in normalization independent of the circuit mechanisms involved in modulating contrast gain and saturation. These results suggest that corticocortical feedback contributes to surround suppression by increasing the visuotopic extent of normalization and, via this mechanism, feedback can play a critical role in contextual information processing. PMID:24910596

  2. Earthquake Loss Scenarios: Warnings about the Extent of Disasters

    Science.gov (United States)

    Wyss, M.; Tolis, S.; Rosset, P.

    2016-12-01

    It is imperative that losses expected due to future earthquakes be estimated. Officials and the public need to be aware of what disaster is likely in store for them in order to reduce the fatalities and efficiently help the injured. Scenarios for earthquake parameters can be constructed to a reasonable accuracy in highly active earthquake belts, based on knowledge of seismotectonics and history. Because of the inherent uncertainties of loss estimates however, it would be desirable that more than one group calculate an estimate for the same area. By discussing these estimates, one may find a consensus of the range of the potential disasters and persuade officials and residents of the reality of the earthquake threat. To model a scenario and estimate earthquake losses requires data sets that are sufficiently accurate of the number of people present, the built environment, and if possible the transmission of seismic waves. As examples we use loss estimates for possible repeats of historic earthquakes in Greece that occurred between -464 and 700. We model future large Greek earthquakes as having M6.8 and rupture lengths of 60 km. In four locations where historic earthquakes with serious losses have occurred, we estimate that 1,000 to 1,500 people might perish, with an additional factor of four people injured. Defining the area of influence of these earthquakes as that with shaking intensities larger and equal to V, we estimate that 1.0 to 2.2 million people in about 2,000 settlements may be affected. We calibrate the QLARM tool for calculating intensities and losses in Greece, using the M6, 1999 Athens earthquake and matching the isoseismal information for six earthquakes, which occurred in Greece during the last 140 years. Comparing fatality numbers that would occur theoretically today with the numbers reported, and correcting for the increase in population, we estimate that the improvement of the building stock has reduced the mortality and injury rate in Greek

  3. Scintigraphic imaging with technetium-99M-labelled ceftizoxime is a reliable technique for the diagnosis of deep sternal wound infection in rats

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Paulo Henrique Nogueira; Diniz, Simone Odilia Fernandes; Cardoso, Valbert Nascimento; Tarabal, Bernardo; Takenaka, Isabella; Braga, Otavio; Vidigal, Paula Vieira Teixeira; Gelape, Claudio Leo; Araujo, Ivana Duval, E-mail: phnc@uol.com.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil)

    2015-07-01

    Purpose: to evaluate whether scintigraphy with technetium-99m-labeled ceftizoxime ({sup 99m}Tc-CFT) can differentiate mediastinitis from aseptic inflammation associated with sternotomy. Methods: twenty female Wistar rats were randomly distributed into four groups: S (control) -partial upper median sternotomy with no treatment; SW (control) - sternotomy and treatment of sternal wounds with bone wax; SB - sternotomy and infection with Staphylococcus aureus; SWB - sternotomy with bone wax treatment and bacterial infection. Scintigraphy with {sup 99m}Tc-CFT was performed eight days after surgery and images were collected 210 and 360 min after infusion of the radiopharmaceutical. Results: no animals exhibited clinical signs of wound infection at the end of the experiment, although histological data verified acute inflammatory response in those experimentally infected with bacteria. Scintigraphic images revealed that tropism of {sup 99m}Tc-CFT to infected sternums was greater than to their non-infected counterparts. Mean counts of radioactivity in bacteria-infected sternal regions (SB and SWB) were significantly higher (p = 0.0007) than those of the respective controls (S and SW).Conclusion: scintigraphy with technetium-99m-labeled ceftizoxime is a method that can potentially detect infection post sternotomy and differentiate from aseptic inflammation in animals experimentally inoculated with S. aureus (author)

  4. Boron nitride nanotubes radiolabeled with ⁹⁹mTc: preparation, physicochemical characterization, biodistribution study, and scintigraphic imaging in Swiss mice.

    Science.gov (United States)

    Soares, Daniel Crístian Ferreira; Ferreira, Tiago Hilário; Ferreira, Carolina de Aguiar; Cardoso, Valbert Nascimento; de Sousa, Edésia Martins Barros

    2012-02-28

    In the present study, boron nitride nanotubes (BNNTs) were synthesized from an innovative process and functionalized with a glycol chitosan polymer in CDTN (Centro de Desenvolvimento da Tecnologia Nuclear) laboratories. As a means of studying their in vivo biodistribution behavior, these nanotubes were radiolabeled with (99m)Tc and injected in mice. Their size, distribution, and homogeneity were determined by photon correlation spectroscopy (PCS), while their zeta potential was determined by laser Doppler anemometry. The morphology and structural organization were evaluated by scanning electron microscopy (SEM). The functionalization in the nanotubes was evaluated by thermogravimetry analysis (TGA) and Fourier transformer infrared spectroscopy. The results showed that BNNTs were obtained and functionalized successfully, reaching a mean size and dispersity deemed adequate for in vivo studies. The BNNTs were also evaluated by ex vivo biodistribution studies and scintigraphic imaging in healthy mice. The results showed that nanostructures, after 24h, having accumulated in the liver, spleen and gut, and eliminated via renal excretion. The findings from this study reveal a potential application of functionalized BNNTs as new potential drugs or radioisotope nanocarriers to be applied in therapeutic procedures. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. A proposal to study the esophageal transit by biomagnetic and scintigraphic study; Uma nova proposta para o estudo do transito esofagiano atraves das tecnicas biomagneticas e cintilograficas

    Energy Technology Data Exchange (ETDEWEB)

    Daghastanli, N.A.; Braga, F.J.H.N.; Baffa, O. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras. Dept. de Fisica; Oliveira, R.B. [Faculdade de Medicina de Ribeirao Preto, SP (Brazil)

    1996-12-31

    The initial results for a new apparatus to study the esophageal transit time is studied in asymptomatic persons for a yogurt bolus (10 ml). The bolus is uniformly labeled with 5 g of ferrite powder (biomagnetic study, B) or 350 MBq of {sup 99m} Tc (scintigraphic study, C). For the B study the detection is made by means two pair of coils in opposite phase excited by a 10 k Hz sinusoidal voltage. The signal response is obtained when the bolus traverses the coils placed on the regions-of-interest (ROIs) of the esophagus (furcula, F and xiphoid process, X) and produces a signal voltage that is measured by a lock-in amplifier Stanford SR530. For C studies an Orbiter Siemens scintillation camera is used linked to a computer. The data analysis shows a (4.1{+-}0.7)s in B studies and (3.7{+-}0.9)s in C studies (R=0.6, P<0.07) 8 refs., 3 figs.

  6. Extent and application of ICU diaries in Germany in 2014

    DEFF Research Database (Denmark)

    Nydahl, Peter; Knueck, Dirk; Egerod, Ingrid

    2015-01-01

    in keeping ICU diaries. CONCLUSION: Six years after the introduction of ICU diaries, ICU nurses in Germany are becoming familiar with the concept. Nursing shortage and bureaucratic challenges have impeded the process of implementation, but the adaption of ICU diaries to German conditions appears......, newsletters, newspapers, lectures and publications in German nursing journals. AIM: The aim of the study was to update our knowledge of the extent and application of ICU diaries in Germany in 2014. DESIGN: The study had a prospective mixed methods multicenter design. METHOD: All 152 ICUs in the two German...... of Germany had implemented diaries and three units were planning to do so. Interviews were conducted with nurses at 14 selected ICUs. Informants reported successful adaption of the diary concept to their culture, but variability in application. No units were identified where all nursing staff participated...

  7. Lymphadenectomy in bladder cancer: What should be the extent?

    Directory of Open Access Journals (Sweden)

    K Muruganandham

    2010-01-01

    Full Text Available The extent of Lymh node dissection (LND during radical cystectomy is a subject of increasing importance with several studies suggesting that an extended LND may improve staging accuracy and outcome. Significant numbers of patients have lymph node metastasis above the boundaries of standard LND. Extended LND yields higher number of lymph nodes which may result in better staging. Various retrospective studies have reported better oncological outcomes with extended LND compared to limited LND. No difference in the mortality and the incidence of lymphocele formation has been found between ′standard′ and ′extended′ LND. Till we have a well-designed randomized controlled trial to address these issues for level 1 evidence, it is not justified to deny our patients the advantages of ′extended′ lymphadenectomy based on the current level of evidence.

  8. Peritoneum and mesenterium. Radiological anatomy and extent of peritoneal diseases

    International Nuclear Information System (INIS)

    Ba-Ssalamah, A.; Bastati, N.; Uffmann, M.; Schima, W.

    2009-01-01

    The abdominal cavity is subdivided into the peritoneal cavity, lined by the parietal peritoneum, and the extraperitoneal space. It extends from the diaphragm to the pelvic floor. The visceral peritoneum covers the intraperitoneal organs and part of the pelvic organs. The parietal and visceral layers of the peritoneum are in sliding contact; the potential space between them is called the peritoneal cavity and is a part of the embryologic abdominal cavity or primitive coelomic duct. To understand the complex anatomical construction of the different variants of plicae and recesses of the peritoneum, an appreciation of the embryologic development of the peritoneal cavity is crucial. This knowledge reflects the understanding of the peritoneal anatomy, deep knowledge of which is very important in determining the cause and extent of peritoneal diseases as well as in decision making when choosing the appropriate therapeutic approach, whether surgery, conservative treatment, or interventional radiology. (orig.) [de

  9. Measuring the extent of overlaps in protected area designations.

    Science.gov (United States)

    Deguignet, Marine; Arnell, Andy; Juffe-Bignoli, Diego; Shi, Yichuan; Bingham, Heather; MacSharry, Brian; Kingston, Naomi

    2017-01-01

    Over the past decades, a number of national policies and international conventions have been implemented to promote the expansion of the world's protected area network, leading to a diversification of protected area strategies, types and designations. As a result, many areas are protected by more than one convention, legal instrument, or other effective means which may result in a lack of clarity around the governance and management regimes of particular locations. We assess the degree to which different designations overlap at global, regional and national levels to understand the extent of this phenomenon at different scales. We then compare the distribution and coverage of these multi-designated areas in the terrestrial and marine realms at the global level and among different regions, and we present the percentage of each county's protected area extent that is under more than one designation. Our findings show that almost a quarter of the world's protected area network is protected through more than one designation. In fact, we have documented up to eight overlapping designations. These overlaps in protected area designations occur in every region of the world, both in the terrestrial and marine realms, but are more common in the terrestrial realm and in some regions, notably Europe. In the terrestrial realm, the most common overlap is between one national and one international designation. In the marine realm, the most common overlap is between any two national designations. Multi-designations are therefore a widespread phenomenon but its implications are not well understood. This analysis identifies, for the first time, multi-designated areas across all designation types. This is a key step to understand how these areas are managed and governed to then move towards integrated and collaborative approaches that consider the different management and conservation objectives of each designation.

  10. A topological insight into restricted Boltzmann machines (extented abstract)

    NARCIS (Netherlands)

    Mocanu, D.C.; Mocanu, E.; Nguyen, H.P.; Gibescu, M.; Liotta, A.

    2016-01-01

    Restricted Boltzmann Machines (RBMs) and models derived from them have been successfully used as basic building blocks in deep neural networks for automatic features extraction, unsupervised weights initialization, but also as standalone models for density estimation, activity recognition and so on.

  11. Integrating remotely sensed surface water extent into continental scale hydrology

    NARCIS (Netherlands)

    Revilla-Romero, Beatriz; Wanders, Niko; Burek, Peter; Salamon, Peter; de Roo, Ad

    2016-01-01

    In hydrological forecasting, data assimilation techniques are employed to improve estimates of initial conditions to update incorrect model states with observational data. However, the limited availability of continuous and up-to-date ground streamflow data is one of the main constraints for

  12. Do indices of coronary conductance after reperfusion reflect the extent of salvaged myocardium?

    Science.gov (United States)

    Shibata, Takahiro; Watanabe, Hisashi; Tsurusaki, Tetsushi; Minai, Kousuke; Ogawa, Takayuki; Iwano, Keiji; Tamura, Tetsutarou; Yoshida, Satoshi; Mutou, Makoto; Imai, Kamon; Horie, Toshinobu; Mochizuki, Seibu

    2004-05-01

    Existing indices of coronary conductance (hyperemic flow-versus-pressure slope index, FPSI, and zero flow pressure, Pzf) have been developed as measures of microcoronary resistance. These indices, however, refer to cases of normal hearts, and there are no reports studying these indices following acute myocardial infarction. In this study, we investigated whether FPSI and Pzf truly measure the extent of myocardial salvage after successful reperfusion therapy. We also developed a new index of zero pressure flow, Fzp. Nineteen patients who underwent successful reperfusion therapy to the proximal portion of the left anterior descending artery (LAD) were studied. After successful reperfusion therapy, a Doppler wire was placed into the LAD. Aortic pressure was recorded in real time. Results from the aortic pressure and flow meter were combined to produce FPSI, Pzf, and Fzp. All cases underwent a resting thallium (Tl) and BMIPP scintigram within five days of successful reperfusion therapy. Infarcted myocardium was estimated using a severity score calculated from the Tl scintigraphy (TlSS), and the BMIPP (BMIPPSS) was estimated using a severity score. Patients with a TlSS/BMIPPSS ratio of less than 0.4 were assigned to the successful salvage group (group S), while the others were assigned to the failed salvage group (group F). FPSI of group F was 1.91 +/- 0.26 m/sec and of group S was 0.92 +/- 0.43 m/sec (P < 0.01). Pzf of group F was 51 +/- 3 mmHg and of group S was 51 +/- 5 mmHg (NS). Fzp of group F was -98 +/- 16 cm/sec and of group S was -46 +/- 4 cm/sec (P < 0.05). FPSI and the new index of Fzp were useful in estimating the extent of myocardial salvage. Our results suggest that the Pzf index could not differentiate between the two groups.

  13. The Extent of Myocardial Injury During Prolonged Targeted Temperature Management After Out-of-Hospital Cardiac Arrest

    DEFF Research Database (Denmark)

    Grejs, Anders Morten; Gjedsted, Jakob; Thygesen, Kristian

    2017-01-01

    AIM: The aim of this study is to evaluate the extent of myocardial injury by cardiac biomarkers during prolonged targeted temperature management of 24 hours vs 48 hours after out-of-hospital cardiac arrest. METHODS: This randomized Scandinavian multicenter study compares the extent of myocardial...... injury estimated by hs-cTnTAUC of prolonged targeted temperature management of 48 hours vs 24 hours, although the CK-MBAUC was significantly higher during 48 hours vs 24 hours. Hence, it seems unlikely that the duration of targeted temperature management has a beneficial effect on the extent...... injury quantified by area under the curve (AUC) of cardiac biomarkers during prolonged targeted temperature management at 33°C ± 1°C of 24 hours and 48 hours, respectively. Through a period of 2.5 years, 161 comatose out-of-hospital cardiac arrest patients were randomized to targeted temperature...

  14. Significance of microscopic extention from 1162 esophageal carcinoma specimens

    International Nuclear Information System (INIS)

    Wang Jun; Zhu Shuchai; Han Chun; Zhang Xin; Xiao Aiqin; Ma Guoxin

    2007-01-01

    Objective: To examine the subclinical microscopic tumor extention along the long axis in 1162 specimens of esophageal carcinoma so as to help define the clinical target volume(CTV) according to the degree of microscopic extention(ME) for radiotherapy for esophageal carcinoma. Methods: 1162 resected esophageal carcinoma specimens originally located in the neck and thorax were studied with special reference to the correlation between upper and lower resection length from the tumor and positive microscopic margin. Another 52 resected esophageal carcinoma specimens were made into pathological giant sections: the actual resection length of upper and para-esophageal normal tissues was compared with that of the lower nor- mal tissues from the tumor, there by, the ratio of shrinkage was obtained and compared. Results: After fixation, microscopic positive margin ratio of the upper resection border in length ≤0.5 cm group was higher than that in length > 0.5 cm group (16.4% vs 4.1%, P=0.000). Microscopic positive margin ratio of the lower resection border in length ≤1.5 cm group was higher than that in length > 1.5 cm group( 8.1% vs 0.4%, P = 0.000). This showed that the positive margin ratio of the upper border was higher than that of the lower border in resection length > 1.5 cm group(3.5% vs 0.4%, P=0. 000). The actual length of upper and lower normal esophageal tissue after having been made into pathological giant sections in 52 patients, was 30% ± 14% and 44% ± 19% of that measured in the operation. Conclusions: Considering the shrinkage of the normal esophagus during fixation, a CTV margin of 2.0 cm along the upper long axis and 3.5 cm along the lower long axis should be chosen for radiotherapy for esophageal carcinoma, according to the ratio of shrinkage. Ascending invasion proportion is higher than the descending invasion in that tumor. (authors)

  15. Methane emissions from global wetlands: An assessment of the uncertainty associated with various wetland extent data sets

    Science.gov (United States)

    Zhang, Bowen; Tian, Hanqin; Lu, Chaoqun; Chen, Guangsheng; Pan, Shufen; Anderson, Christopher; Poulter, Benjamin

    2017-09-01

    A wide range of estimates on global wetland methane (CH4) fluxes has been reported during the recent two decades. This gives rise to urgent needs to clarify and identify the uncertainty sources, and conclude a reconciled estimate for global CH4 fluxes from wetlands. Most estimates by using bottom-up approach rely on wetland data sets, but these data sets show largely inconsistent in terms of both wetland extent and spatiotemporal distribution. A quantitative assessment of uncertainties associated with these discrepancies among wetland data sets has not been well investigated yet. By comparing the five widely used global wetland data sets (GISS, GLWD, Kaplan, GIEMS and SWAMPS-GLWD), it this study, we found large differences in the wetland extent, ranging from 5.3 to 10.2 million km2, as well as their spatial and temporal distributions among the five data sets. These discrepancies in wetland data sets resulted in large bias in model-estimated global wetland CH4 emissions as simulated by using the Dynamic Land Ecosystem Model (DLEM). The model simulations indicated that the mean global wetland CH4 emissions during 2000-2007 were 177.2 ± 49.7 Tg CH4 yr-1, based on the five different data sets. The tropical regions contributed the largest portion of estimated CH4 emissions from global wetlands, but also had the largest discrepancy. Among six continents, the largest uncertainty was found in South America. Thus, the improved estimates of wetland extent and CH4 emissions in the tropical regions and South America would be a critical step toward an accurate estimate of global CH4 emissions. This uncertainty analysis also reveals an important need for our scientific community to generate a global scale wetland data set with higher spatial resolution and shorter time interval, by integrating multiple sources of field and satellite data with modeling approaches, for cross-scale extrapolation.

  16. Federal Education Tax Benefits: Who Receives Them and to What Extent Do They Shape the Price of College Attendance? Stats in Brief. NCES 2012-212

    Science.gov (United States)

    Radford, Alexandria Walton; Berkner, Lutz

    2011-01-01

    This Statistics in Brief applies IRS rules and data to a nationally representative sample of 2007-08 undergraduates to estimate who received education tax benefits and looks at the extent to which these benefits shaped their price of college attendance. Key findings include: (1) Nearly one-half of all 2007-08 undergraduates were estimated to have…

  17. Distracted walking: Examining the extent to pedestrian safety problems

    Directory of Open Access Journals (Sweden)

    Judith Mwakalonge

    2015-10-01

    Full Text Available Pedestrians, much like drivers, have always been engaged in multi-tasking like using hand-held devices, listening to music, snacking, or reading while walking. The effects are similar to those experienced by distracted drivers. However, distracted walking has not received similar policies and effective interventions as distracted driving to improve pedestrian safety. This study reviewed the state-of-practice on policies, campaigns, available data, identified research needs, and opportunities pertaining to distracted walking. A comprehensive review of literature revealed that some of the agencies/organizations disseminate useful information about certain distracting activities that pedestrians should avoid while walking to improve their safety. Various walking safety rules/tips have been given, such as not wearing headphones or talking on a cell phone while crossing a street, keeping the volume down, hanging up the phone while walking, being aware of traffic, and avoiding distractions like walking with texting. The majority of the past observational-based and experimental-based studies reviewed in this study on distracted walking is in agreement that there is a positive correlation between distraction and unsafe walking behavior. However, limitations of the existing crash data suggest that distracted walking may not be a severe threat to the public health. Current pedestrian crash data provide insufficient information for researchers to examine the extent to which distracted walking causes and/or contributes to actual pedestrian safety problems.

  18. The extent and nature of alcohol advertising on Australian television.

    Science.gov (United States)

    Pettigrew, Simone; Roberts, Michele; Pescud, Melanie; Chapman, Kathy; Quester, Pascale; Miller, Caroline

    2012-09-01

    Current alcohol guidelines in Australia recommend minimising alcohol consumption, especially among minors. This study investigated (i) the extent to which children and the general population are exposed to television advertisements that endorse alcohol consumption and (ii) the themes used in these advertisements. A content analysis was conducted on alcohol advertisements aired over two months in major Australian cities. The advertisements were coded according to the products that were promoted, the themes that were employed, and the time of exposure. Advertising placement expenditure was also captured. In total, 2810 alcohol advertisements were aired, representing one in 10 beverage advertisements. Advertisement placement expenditure for alcohol products in the five cities over the two months was $15.8 million. Around half of all alcohol advertisements appeared during children's popular viewing times. The most common themes used were humour, friendship/mateship and value for money. Children and adults are regularly exposed to advertisements that depict alcohol consumption as fun, social and inexpensive. Such messages may reinforce existing alcohol-related cultural norms that prevent many Australians from meeting current intake guidelines. © 2012 Australasian Professional Society on Alcohol and other Drugs.

  19. The nature and extent of college student hazing.

    Science.gov (United States)

    Allan, Elizabeth J; Madden, Mary

    2012-01-01

    This study explored the nature and extent of college student hazing in the USA. Hazing, a form of interpersonal violence, can jeopardize the health and safety of students. Using a web-based survey, data were collected from 11,482 undergraduate students, aged 18-25 years, who attended one of 53 colleges and universities. Additionally, researchers interviewed 300 students and staff at 18 of the campuses. Results reveal hazing among USA college students is widespread and involves a range of student organizations and athletic teams. Alcohol consumption, humiliation, isolation, sleep-deprivation and sex acts are hazing practices common across student groups. Furthermore, there is a large gap between the number of students who report experience with hazing behaviors and those that label their experience as hazing. To date, hazing prevention efforts in post-secondary education have focused largely on students in fraternities/sororities and intercollegiate athletes. Findings from this study can inform development of more comprehensive and research-based hazing prevention efforts that target a wider range of student groups. Further, data can serve as a baseline from which to measure changes in college student hazing over time.

  20. Extent and modes of physics instruction in European dental schools.

    Science.gov (United States)

    Letić, Milorad; Popović, Gorjana

    2013-01-01

    Changes in dental education towards integration of sciences and convergence of curricula have affected instruction in physics. Earlier studies of undergraduate curricula make possible comparisons in physics instruction. For this study, the websites of 245 European dental schools were explored, and information about the curriculum was found on 213 sites. Physics instruction in the form of a separate course was found in 63 percent of these schools, with eighty-two hours and 5.9 European Credit Transfer and Accumulation System (ECTS) credits on average. Physics integrated with other subjects or into modules was found in 19 percent of these schools. Half of these schools had on average sixty-one hours and 6.9 ECTS credits devoted to physics. Eighteen percent of the schools had no noticeable obligatory physics instruction, but in half of them physics was found to be required or accepted on admission, included in other subjects, or appeared as an elective course. In 122 dental schools, the extent of physics instruction was found to be between forty and 120 contact hours. Physics instruction has been reduced by up to 14 percent in the last fourteen years in the group of eleven countries that were members of the European Union (EU) in 1997, but by approximately 30 percent in last five years in the group of ten Accession Countries to the EU.

  1. The additional diagnostic value of a single-session combined scintigraphic and ultrasonographic examination in patients with thyroid and parathyroid diseases.

    Science.gov (United States)

    Gedik, G K; Bozkurt, F M; Ugur, O; Grassetto, G; Rubello, D

    2008-09-01

    The aim of this study was to investigate the diagnostic efficacy and the clinical impact of scintigraphy combined with ultrasonography (USG) in the management of thyroid and parathyroid disorders in a large series of patients. A total of 387 consecutive patients referred to the Nuclear Medicine Department of Hacettepe University in the period from January to September 2007 for investigating a thyroid (N. 339 patients: 232 females and 107 males, mean age+/-SD=48.9+/-13.6 years) or a parathyroid disease (N. 48 patients: 34 females and 14 males, mean age+/-SD=47.4+/-9.6 years) were prospectively evaluated, systematically performing both scintigraphy and USG in a single-day session. All the examinations were independently reviewed by two nuclear medicine physicians; in cases of discrepancy (3%) a final diagnosis was reached by consensus. For thyroid pathologies, USG results were considered to provide additional diagnostic information over scintigraphy: 1) if more nodules were identified; 2) if an irregular hyperactive area at scintigraphy suspicious for the presence of a nodule was clearly characterized at USG; 3) if a nodule missed at scintigraphy because of small size (thyroid diseases, scintigraphy was considered to provide additional diagnostic information over USG, if the functional status of a diffuse or uni- or multi-nodular goiter were clearly defined at scintigraphy. In parathyroid diseases, scintigraphy was considered to provide additional diagnostic information over USG, if the differential diagnosis between a lymph node or a muscle or a vessel depicted at USG was clearly defined as a parathyroid enlargement at scintigraphy. Lastly, the clinical impact of the single-day combined scintigraphic/USG protocol was evaluated. USG. In the thyroid diseases group, USG was particularly useful: 1) to detect additional nodules in glands with suppressed thyroid tissue; 2) to disclose small thyroid nodules (thyroid diseases group, scintigraphy was particularly useful: 1

  2. Filling the gap: Using fishers' knowledge to map the extent and intensity of fishing activity.

    Science.gov (United States)

    Szostek, Claire L; Murray, Lee G; Bell, Ewen; Kaiser, Michel J

    2017-08-01

    Knowledge of the extent and intensity of fishing activities is critical to inform management in relation to fishing impacts on marine conservation features. Such information can also provide insight into the potential socio-economic impacts of closures (or other restrictions) of fishing grounds that could occur through the future designation of Marine Conservation Zones (MCZs). We assessed the accuracy and validity of fishing effort data (spatial extent and relative effort) obtained from Fishers' Local Knowledge (LK) data compared to that derived from Vessel Monitoring System (VMS) data for a high-value shellfish fishery, the king scallop (Pecten maximus L.) dredge fishery in the English Channel. The spatial distribution of fishing effort from LK significantly correlated with VMS data and the correlation increased with increasing grid cell resolution. Using a larger grid cell size for data aggregation increases the estimation of the total area of seabed impacted by the fishery. In the absence of historical VMS data for vessels ≤15 m LOA (Length Overall), LK data for the inshore fleet provided important insights into the relative effort of the inshore (<6 NM from land) king scallop fishing fleet in the English Channel. The LK data provided a good representation of the spatial extent of inshore fishing activity, whereas representation of the offshore fishery was more precautionary in terms of defining total impact. Significantly, the data highlighted frequently fished areas of particular importance to the inshore fleet. In the absence of independent sources of geospatial information, the use of LK can inform the development of marine planning in relation to both sustainable fishing and conservation objectives, and has application in both developed and developing countries where VMS technology is not utilised in fisheries management. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. THE USE OF LIDAR AND VOLUNTEERED GEOGRAPHIC INFORMATION TO MAP FLOOD EXTENTS AND INUNDATION

    Directory of Open Access Journals (Sweden)

    K. McDougall

    2012-07-01

    Full Text Available Floods are one of the most destructive natural disasters that threaten communities and properties. In recent decades, flooding has claimed more lives, destroyed more houses and ruined more agricultural land than any other natural hazard. The accurate prediction of the areas of inundation from flooding is critical to saving lives and property, but relies heavily on accurate digital elevation and hydrologic models. The 2011 Brisbane floods provided a unique opportunity to capture high resolution digital aerial imagery as the floods neared their peak, allowing the capture of areas of inundation over the various city suburbs. This high quality imagery, together with accurate LiDAR data over the area and publically available volunteered geographic imagery through repositories such as Flickr, enabled the reconstruction of flood extents and the assessment of both area and depth of inundation for the assessment of damage. In this study, approximately 20 images of flood damaged properties were utilised to identify the peak of the flood. Accurate position and height values were determined through the use of RTK GPS and conventional survey methods. This information was then utilised in conjunction with river gauge information to generate a digital flood surface. The LiDAR generated DEM was then intersected with the flood surface to reconstruct the area of inundation. The model determined areas of inundation were then compared to the mapped flood extent from the high resolution digital imagery to assess the accuracy of the process. The paper concludes that accurate flood extent prediction or mapping is possible through this method, although its accuracy is dependent on the number and location of sampled points. The utilisation of LiDAR generated DEMs and DSMs can also provide an excellent mechanism to estimate depths of inundation and hence flood damage

  4. The Use of LIDAR and Volunteered Geographic Information to Map Flood Extents and Inundation

    Science.gov (United States)

    McDougall, K.; Temple-Watts, P.

    2012-07-01

    Floods are one of the most destructive natural disasters that threaten communities and properties. In recent decades, flooding has claimed more lives, destroyed more houses and ruined more agricultural land than any other natural hazard. The accurate prediction of the areas of inundation from flooding is critical to saving lives and property, but relies heavily on accurate digital elevation and hydrologic models. The 2011 Brisbane floods provided a unique opportunity to capture high resolution digital aerial imagery as the floods neared their peak, allowing the capture of areas of inundation over the various city suburbs. This high quality imagery, together with accurate LiDAR data over the area and publically available volunteered geographic imagery through repositories such as Flickr, enabled the reconstruction of flood extents and the assessment of both area and depth of inundation for the assessment of damage. In this study, approximately 20 images of flood damaged properties were utilised to identify the peak of the flood. Accurate position and height values were determined through the use of RTK GPS and conventional survey methods. This information was then utilised in conjunction with river gauge information to generate a digital flood surface. The LiDAR generated DEM was then intersected with the flood surface to reconstruct the area of inundation. The model determined areas of inundation were then compared to the mapped flood extent from the high resolution digital imagery to assess the accuracy of the process. The paper concludes that accurate flood extent prediction or mapping is possible through this method, although its accuracy is dependent on the number and location of sampled points. The utilisation of LiDAR generated DEMs and DSMs can also provide an excellent mechanism to estimate depths of inundation and hence flood damage

  5. A global view of shifting cultivation: Recent, current, and future extent.

    Directory of Open Access Journals (Sweden)

    Andreas Heinimann

    Full Text Available Mosaic landscapes under shifting cultivation, with their dynamic mix of managed and natural land covers, often fall through the cracks in remote sensing-based land cover and land use classifications, as these are unable to adequately capture such landscapes' dynamic nature and complex spectral and spatial signatures. But information about such landscapes is urgently needed to improve the outcomes of global earth system modelling and large-scale carbon and greenhouse gas accounting. This study combines existing global Landsat-based deforestation data covering the years 2000 to 2014 with very high-resolution satellite imagery to visually detect the specific spatio-temporal pattern of shifting cultivation at a one-degree cell resolution worldwide. The accuracy levels of our classification were high with an overall accuracy above 87%. We estimate the current global extent of shifting cultivation and compare it to other current global mapping endeavors as well as results of literature searches. Based on an expert survey, we make a first attempt at estimating past trends as well as possible future trends in the global distribution of shifting cultivation until the end of the 21st century. With 62% of the investigated one-degree cells in the humid and sub-humid tropics currently showing signs of shifting cultivation-the majority in the Americas (41% and Africa (37%-this form of cultivation remains widespread, and it would be wrong to speak of its general global demise in the last decades. We estimate that shifting cultivation landscapes currently cover roughly 280 million hectares worldwide, including both cultivated fields and fallows. While only an approximation, this estimate is clearly smaller than the areas mentioned in the literature which range up to 1,000 million hectares. Based on our expert survey and historical trends we estimate a possible strong decrease in shifting cultivation over the next decades, raising issues of livelihood security

  6. Relation between myocardial response to dobutamine stress and sympathetic nerve activation in patients with idiopathic dilated cardiomyopathy. A comparison of 123I-MIBG scintigraphic and echocardiographic data

    International Nuclear Information System (INIS)

    Naruse, Hitoshi; Arii, Tohru; Kondo, Tomohiro

    2000-01-01

    It is likely that a close association exists between findings obtained by two methods: dobutamine stress echocardiography and 123 I-MIBG scintigraphy. Both of these methods are associated with β-adrenergic receptor mechanisms. This study was conducted to demonstrate the relation between myocardial response to dobutamine stress and sympathetic nerve release of norepinephrine in the failing heart. In 12 patents with heart failure due to idiopathic dilated cardiomyopathy, the myocardial effects of dobutamine stress were evaluated by low-dose dobutamine stress echocardiography; and sympathetic nerve function was evaluated by scintigraphic imaging with iodine-123[ 123 I]meta-iodobenzylguanidine (MIBG), an analogue of norepinephrine. Echocardiography provided quantitative assessment of wall motion and left ventricular dilation; radiotracer studies with 123 I-MIBG provided quantitative assessment of the heart-to-mediastinum (H/M) uptake ratio and washout rate. Results showed that H/M correlated with baseline wall motion (r=0.682, p=0.0146), wall motion after dobutamine stress (r=0.758, p=0.0043), the change in wall motion (r=0.667, p=0.0178), and with left ventricular diastolic diameter (r=0.837, p=0.0007). In addition, the 123 I-MIBG washout rate correlated with baseline wall motion (r=0.608, p=0.0360), wall motion after dobutamine stress (r=0.703, p=0.0107), and with the change in wall motion (r=0.664, p=0.0185). Wall motion, especially in the myocardial response to dobutamine stress, is related to sympathetic nerve activity in heart failure. (author)

  7. Scintigraphic study of palpable breast nodes with {sup 99m} Tc-tetrofosmin; Estudo cintilografico de nodulos palpaveis da mama com {sup 99m} Tc - tetrofosmin

    Energy Technology Data Exchange (ETDEWEB)

    Pellini, Marcos Pinto; Fonseca, Lea Mirian Barbosa da [Universidade Federal, Rio de Janeiro, RJ (Brazil). Faculdade de Medicina. Dept. de Radiologia; Amarante Junior, Jose Luiz de Medeiros [Hospital Naval Marcilio Dias, Rio de Janeiro, RJ (Brazil). Servico de Medicina Nuclear; Fabricio, Maria Ines Menescal [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Ginecologia

    1998-12-01

    In Brazil, breast carcinoma has the greater incidence among women. In 1996, about 31,210 new cases were diagnosed. The purpose of this study is to determine if {sup 99m} technetium-tetrofosmin preferentially concentrates within malignant palpable breast nodes, distinguishing them from the benign lumps. Fifth-four consecutive and unsolicited women, mean age 47.5 +- 10.7 years, with palpable nodes in breast, underwent breast scintigraphy with {sup 99m} technetium-tetrofosmin and excisional biopsy or fine needle puncture within interval eight weeks. Histopathologic studies demonstrated 13 cysts, 1 cyst with local inflammation, 11 fibroadenoma, 2 fibrodysplasias, 3 fibroadenomas with high cellularity, 1 fibrocystic change with local inflammation, 23 invasive intraductal carcinomas and 1 invasive lobular carcinoma. The nodes ranged from 10 to 100 mm in greater diameter. The scintigraphic study yielded 30 true-negative cases, 24 true-positives, no false-negative and 1 false-positive. This case was a fibrocystic lump with local inflammation. Two patients had metastases in axillary lymph nodes, well detected in scintigraphy. The statistic analysis showed: sensitivity, 100%; specificity, 96.8%; accuracy, 98.2%; negative predictive value, 100%; positive predictive value, 96.0%. Nonparametric tests of Fisher and Chi-square rejected the antithesis at a confidence interval of 99.9% (p < 0.001). We concluded that {sup 99m} technetium-tetrofosmin preferentially concentrates in malignant palpable breast nodes and can help to distinguish them from the benign tumors with with very high accuracy. (author)

  8. *sp131*I-3-iodobenzylguanidine (*sp131*I-3-IBG) as a scintigraphic agent for the visualization of adrenal medulla tumors

    International Nuclear Information System (INIS)

    Heggeli, D.E.; Brorson, B.I.; Bremper, P.O.

    1983-06-01

    A method of labelling 3-iodobenzylguanidine with *sp131*I is described. 3-IBG . 0.5 H*sb2*SO*sb4* and Cu(II)SO*sb4* were dissolved in a 0.1 M NH*sb4*H*sb2*PO*sb4* buffer and mixed with *sp131*I-NaI. The solution was evaporated to dryness by heating. After addition of water, the solution was heated with reflux for two hours. The I*sp-* ions were removed after labelling by anionic exchange chromatography. The final product was made isotonic and bacteriostatic by the addition of acetate buffer, saline and benzylalcohol. The product was filtered through a membrane filter with a pore size of 0.22*my*m and was apyrogenically tested by limulus test. The tumors of adrenal medulla, pheochromocytomas and neuroplastomas may in some cases be small or located extra-adrenally. In those cases *sp131*I-labelled 3-IBG is a valuable tool, since 3-IBG concentrates in adrenal medulla tumors because ot its analogy to the catecholamines. Injecting a dose of 0.5 mCi *sp131*I-3-IBG (2.5 mCi/mg), which is an adult dose, allows the scintigraphic localization of the tumours, thus guiding the surgeon. Adrenal uptake in mice and dog is described in the report, as well as a rapid method for the control of radiochemical purity. The radioactive concentration of the *sp131*I-3-IBG has been found to be important for the radiochemical stability of the product. (RF)

  9. Parameter Estimation

    DEFF Research Database (Denmark)

    Sales-Cruz, Mauricio; Heitzig, Martina; Cameron, Ian

    2011-01-01

    of optimisation techniques coupled with dynamic solution of the underlying model. Linear and nonlinear approaches to parameter estimation are investigated. There is also the application of maximum likelihood principles in the estimation of parameters, as well as the use of orthogonal collocation to generate a set......In this chapter the importance of parameter estimation in model development is illustrated through various applications related to reaction systems. In particular, rate constants in a reaction system are obtained through parameter estimation methods. These approaches often require the application...... of algebraic equations as the basis for parameter estimation.These approaches are illustrated using estimations of kinetic constants from reaction system models....

  10. Extent of lymph node dissection for adenocarcinoma of the stomach.

    Science.gov (United States)

    Mocellin, Simone; McCulloch, Peter; Kazi, Hussain; Gama-Rodrigues, Joaquin J; Yuan, Yuhong; Nitti, Donato

    2015-08-12

    The impact of lymphadenectomy extent on the survival of patients with primary resectable gastric carcinoma is debated. We aimed to systematically review and meta-analyze the evidence on the impact of the three main types of progressively more extended lymph node dissection (that is, D1, D2 and D3 lymphadenectomy) on the clinical outcome of patients with primary resectable carcinoma of the stomach. The primary objective was to assess the impact of lymphadenectomy extent on survival (overall survival [OS], disease specific survival [DSS] and disease free survival [DFS]). The secondary aim was to assess the impact of lymphadenectomy on post-operative mortality. We searched CENTRAL, MEDLINE and EMBASE until 2001, including references from relevant articles and conference proceedings. We also contacted known researchers in the field. For the updated review, CENTRAL, MEDLINE and EMBASE were searched from 2001 to February 2015. We considered randomized controlled trials (RCTs) comparing the three main types of lymph node dissection (i.e., D1, D2 and D3 lymphadenectomy) in patients with primary non-metastatic resectable carcinoma of the stomach. Two authors independently extracted data from the included studies. Hazard ratios (HR) and relative risks (RR) along with their 95% confidence intervals (CI) were used to measure differences in survival and mortality rates between trial arms, respectively. Potential sources of between-study heterogeneity were investigated by means of subgroup and sensitivity analyses. The same two authors independently assessed the risk of bias of eligible studies according to the standards of the Cochrane Collaboration and the quality of the overall evidence based on the GRADE (Grades of Recommendation, Assessment, Development and Evaluation) criteria. Eight RCTs (enrolling 2515 patients) met the inclusion criteria. Three RCTs (all performed in Asian countries) compared D3 with D2 lymphadenectomy: data suggested no significant difference in OS

  11. Migratory decisions in birds: Extent of genetic versus environmental control

    Science.gov (United States)

    Ogonowski, M.S.; Conway, C.J.

    2009-01-01

    Migration is one of the most spectacular of animal behaviors and is prevalent across a broad array of taxa. In birds, we know much about the physiological basis of how birds migrate, but less about the relative contribution of genetic versus environmental factors in controlling migratory tendency. To evaluate the extent to which migratory decisions are genetically determined, we examined whether individual western burrowing owls (Athene cunicularia hypugaea) change their migratory tendency from one year to the next at two sites in southern Arizona. We also evaluated the heritability of migratory decisions by using logistic regression to examine the association between the migratory tendency of burrowing owl parents and their offspring. The probability of migrating decreased with age in both sexes and adult males were less migratory than females. Individual owls sometimes changed their migratory tendency from one year to the next, but changes were one-directional: adults that were residents during winter 2004-2005 remained residents the following winter, but 47% of adults that were migrants in winter 2004-2005 became residents the following winter. We found no evidence for an association between the migratory tendency of hatch-year owls and their male or female parents. Migratory tendency of hatch-year owls did not differ between years, study sites or sexes or vary by hatching date. Experimental provision of supplemental food did not affect these relationships. All of our results suggest that heritability of migratory tendency in burrowing owls is low, and that intraspecific variation in migratory tendency is likely due to: (1) environmental factors, or (2) a combination of environmental factors and non-additive genetic variation. The fact that an individual's migratory tendency can change across years implies that widespread anthropogenic changes (i.e., climate change or changes in land use) could potentially cause widespread changes in the migratory tendency of

  12. Rate and extent of aqueous perchlorate removal by iron surfaces.

    Science.gov (United States)

    Moore, Angela M; De Leon, Corinne H; Young, Thomas M

    2003-07-15

    The rate and extent of perchlorate reduction on several types of iron metal was studied in batch and column reactors. Mass balances performed on the batch experiments indicate that perchlorate is initially sorbed to the iron surface, followed by a reduction to chloride. Perchlorate removal was proportional to the iron dosage in the batch reactors, with up to 66% removal in 336 h in the highest dosage system (1.25 g mL(-1)). Surface-normalized reaction rates among three commercial sources of iron filings were similar for acid-washed samples. The most significant perchlorate removal occurred in solutions with slightly acidic or near-neutral initial pH values. Surface mediation of the reaction is supported by the absence of reduction in batch experiments with soluble Fe2+ and also by the similarity in specific reaction rate constants (kSA) determined for three different iron types. Elevated soluble chloride concentrations significantly inhibited perchlorate reduction, and lower removal rates were observed for iron samples with higher amounts of background chloride contamination. Perchlorate reduction was not observed on electrolytic sources of iron or on a mixed-phase oxide (Fe3O4), suggesting that the reactive iron phase is neither pure zerovalent iron nor the mixed oxide alone. A mixed valence iron hydr(oxide) coating or a sorbed Fe2+ surface complex represent the most likely sites for the reaction. The observed reaction rates are too slow for immediate use in remediation system design, but the findings may provide a basis for future development of cost-effective abiotic perchlorate removal techniques.

  13. The extent of use of online pharmacies in Saudi Arabia.

    Science.gov (United States)

    Abanmy, Norah

    2017-09-01

    Online pharmacies sell medicine over the Internet and deliver them by mail. The main objective of this study is to explore the extent of use of online pharmacies in Saudi Arabia which will be useful for the scientific community and regulators. An Arabic survey questionnaire was developed for this study. The questionnaire was distributed via email and social media. Four sections were created to cover the objectives: experience with online shopping in general, demographics, awareness of the existence and customer experiences of buying medicine online, and reasons for buying/not buying medicine online. A total of 633 responses were collected. Around 69% (437) of them were female and the majority (256, 40.4%) was in the age range 26-40. Only 23.1% (146) were aware of the existence of online pharmacies where 2.7% (17) of them had bought a medicine over the Internet and 15 (88.2%) respondents out of the 17 was satisfied with the process. Lack of awareness of the availability of such services was the main reason for not buying medicines online. Many respondents (263, 42.7%) were willing to try an online pharmacy, although majorities (243, 45.9%) were unable to differentiate between legal and illegal online pharmacies. The largest categories of products respondents were willing to buy them online were nonprescription medicines and cosmetics. The popularity of purchasing medicines over the Internet is still low in Saudi Arabia. However, because the majority of respondents are willing to purchase medicines online, efforts should be made by the Saudi FDA to set regulations and monitor this activity.

  14. Scintigraphic assessment of normal values of lower limb perfusion under stress and rest, with possible clinical applications

    International Nuclear Information System (INIS)

    Malkowski, B.; Zajac, A.; Maziarz, Z.; Zaborowski, G.; Ryglewska-Brzozowska, M.; Malara, A.; Tryniszewski, W.

    2005-01-01

    The lack of a range of normal values of perfusion in the lower limbs during stress and at rest narrows the use of this type of diagnostic tool to the estimation of the current state of relative perfusion without indications of the presence or level of perfusion disturbances. Numerous reports on early changes in endothelium reactivity (depending on disease and degree of vessel pathology) encouraged us to assess lower limb perfusion in healthy people. Our goal was to 1) work out a program and method which would enable lower limb perfusion assessment under stress and at rest in patients without signs of lower limb circulation deprivation and 2) establish the normal range of indexes of lower limb perfusion under stress and at rest which would enable their use in the diagnostics of lower limb muscle circulation. 33 male patients aged between 25 to 45 years (mean: 35.30 ± 6.04) without signs of circulatory problems were entered into the study. To exclude circulatory disturbances, Doppler USG, blood pressure, and laboratory tests were performed on every patient at rest 5 min. after the injection of 11.1 MBq/kg 99 mTc MIBI. Whole body as well as thigh and calf scintigrams were made with an ELSCINT SP6HR gamma-camera. The symmetry of the thigh and calf perfusion (WSU, WSP) and the indexes of the thigh (WPLU, WPPU) and calf (WPLP, WSPP) perfusion of both lower limbs were estimated. At rest: WSP: 96.47% ±1.02, WSP: 96.47% ± 1.02, WPLP: 9.77 ± 0.32, WPPP: 9.78 ± 0.31, WPLU: 8.45 ± 0.22, WPPU: 8.48 ± 0.22. Under stress: WSP: 96.69% ± 1.32, WSU: 96.41% ± 1.20, WPLP: 8.78 ± 0.26, WPPP: 8.81 ± 0.25, WPLU: 7.77 ± 0.25, WPPU: 7.82 ± 0.26. Anamnesis, additional studies, and laboratory tests in the group examined did not show any circulatory disturbances. The estimated values in patients without circulatory disturbances are similar and within a narrow range, which allows us to calculate the norms of lower limb perfusion at rest and under stress. The determined normal

  15. Estimation of infarct size by myocardial emission computed tomography with thallium-201 and its relation to creatine kinase-MB release after myocardial infarction in man

    International Nuclear Information System (INIS)

    Tamaki, S.; Nakajima, H.; Murakami, T.

    1982-01-01

    Emission computed tomography (ECT) for thallium-201 ( 201 Tl) myocardial imaging was evaluated in estimating infarct size (IS). In 18 patients in whom IS was estimated enzymatically at the time of the acute episode, planar 201 Tl perfusion scintigraphy and ECT with a rotating gamma camera were performed 4 weeks after the first myocardial infarction. From the size of 201 Tl perfusion defects, the infarct area in planar images and the infarct volume in reconsturcted ECT images were measured by computerized planimetry. When scintigraphic IS was compared with the accumulated creatine kinase-MB isoenzyme release (CK-MBr), infarct volume determined from ECT correlated closely with CK-MBr (r=0.89), whereas infarct area measured from planar images correlated less satisfactorily with the enzymatic IS (for an average infarct area from three views, r=0.69; for the largest infarct area, r=0.73). Although conventional scintigraphic evaluation is useful for detecting and localizing infarction, quantification of ischemic injury with this two-dimensional technique has a significant inherent limitation. The ECT approach can provide a more accurate three-dimensional quantitative estimate of infarction, and can corroborate the enzymatic estimate of IS

  16. Estimation of infarct size by myocardial emission computed tomography with 201Tl and its relation to creatine kinase-MB release after myocardial infarction in man

    International Nuclear Information System (INIS)

    Tamaki, S.; Nakajima, H.; Murakami, T.

    1982-01-01

    We evaluated emission computed tomography (ECT) 201 Tl myocardial imaging in estimating infarct size (IS). In 18 patients in whom IS was estimated enzymatically at the time of the acute episode, planar 201 Tl perfusion scintigraphy and ECT with a rotating gamma camera were performed 4 weeks after the first myocardial infarction. From the size of 201 Tl perfusion defects, the infarct area in planar images and the infarct volume in reconstructed ECT images were measured by computerized planimetry. When scintigraphic IS was compared with the accumulated creatine kinase-MB isoenzyme release (CK-MBr), infarct volume determined from ECT correlated closely with CK-MBr (r . 0.89), whereas infarct area measured from planar images correlated less satisfactorily with the enzymatic IS (for an average infarct area from three views, r . 0.69; for the largest infarct area, r . 0.73). Although conventional scintigraphic evaluation is useful for detecting and localizing infarction, quantification of ischemic injury with this two-dimensional technique has a significant inherent limitation. The ECT approach can provide a more accurate three-dimensional quantitative estimate of infarction, and can corroborate the enzymatic estimate of IS

  17. A framework for quantifying the extent of impact to plants from linear construction.

    Science.gov (United States)

    Xiao, Jun; Shi, Peng; Wang, Ya-Feng; Yu, Yang; Yang, Lei

    2017-05-30

    We present a novel framework that accurately evaluates the extent of a linear project's effect from the variability of the structure of the plant community while avoiding interference caused by pioneer species and invasive species. This framework was based on the change of dominant species in the plant community affected by construction. TWINSPAN classification and variation of the integrated importance value (IIV) of each plant species group were used to characterize the process of change in the structure of the plant community. Indicator species group and its inflection point were defined and used to judge the extent of the effects of pipelines. Our findings revealed that dominant species in the working area of the pipeline construction were different from the original plant communities. With the disturbance decreased, the composition and structure of the plant communities gradually changed. We considered the outer limit of the area affected by the construction to be the first area in which the plant community reached a steady state and was similar to the original community. The framework could be used in the post eco-environment impact assessment of linear construction to estimate the intensity of disturbance and recovery condition.

  18. The Extent and Implications of the Microclimatic Conditions in the Urban Environment: A Vienna Case Study

    Directory of Open Access Journals (Sweden)

    Milena Vuckovic

    2017-01-01

    Full Text Available Recent challenges in the realm of urban studies concern better understanding of microclimatic conditions. Changes in urban climate affect cities at local and global scales, with consequences for human health, thermal comfort, building energy use, and anthropogenic emissions. The extent of these impacts may vary due to different morphologies and materials of the built environment. The present contribution summarizes the results of a multi-year effort concerned with the extent and implications of urban heat in Vienna, Austria. For this purpose, high-resolution weather data across six locations are obtained and analyzed. This allowed for an objective assessment of urban-level climatic circumstances across distinct low-density and high-density typologies. Subsequently, a systematic framework was developed for identification of essential properties of the built environment (geometric and material-related that are hypothesized to influence microclimate variation. Results point to a number of related (positive and negative correlations with microclimatic tendencies. Additionally, the impact of this location-specific weather data on building performance simulation results is evaluated. The results suggest that buildings' thermal performance is significantly influenced by location-specific microclimatic conditions with variation of mean annual heating load across locations of up to 16.1 kWhm−2·a−1. The use of location-independent weather data sources (e.g., standardized weather files for building performance estimations can, thus, result in considerable errors.

  19. Data-adaptive Harmonic Decomposition and Real-time Prediction of Arctic Sea Ice Extent

    Science.gov (United States)

    Kondrashov, Dmitri; Chekroun, Mickael; Ghil, Michael

    2017-04-01

    Decline in the Arctic sea ice extent (SIE) has profound socio-economic implications and is a focus of active scientific research. Of particular interest is prediction of SIE on subseasonal time scales, i.e. from early summer into fall, when sea ice coverage in Arctic reaches its minimum. However, subseasonal forecasting of SIE is very challenging due to the high variability of ocean and atmosphere over Arctic in summer, as well as shortness of observational data and inadequacies of the physics-based models to simulate sea-ice dynamics. The Sea Ice Outlook (SIO) by Sea Ice Prediction Network (SIPN, http://www.arcus.org/sipn) is a collaborative effort to facilitate and improve subseasonal prediction of September SIE by physics-based and data-driven statistical models. Data-adaptive Harmonic Decomposition (DAH) and Multilayer Stuart-Landau Models (MSLM) techniques [Chekroun and Kondrashov, 2017], have been successfully applied to the nonlinear stochastic modeling, as well as retrospective and real-time forecasting of Multisensor Analyzed Sea Ice Extent (MASIE) dataset in key four Arctic regions. In particular, DAH-MSLM predictions outperformed most statistical models and physics-based models in real-time 2016 SIO submissions. The key success factors are associated with DAH ability to disentangle complex regional dynamics of MASIE by data-adaptive harmonic spatio-temporal patterns that reduce the data-driven modeling effort to elemental MSLMs stacked per frequency with fixed and small number of model coefficients to estimate.

  20. Nuclear scintigraphic assessment of intestinal dysfunction after combined treatment with 9-amino-20(S)-camptothecin (9-AC) and irradiation

    International Nuclear Information System (INIS)

    Kirichenko, Alexander V.; Mason, Kathryn; Straume, Martin; Teates, Charles D.; Rich, Tyvin A.

    2000-01-01

    Purpose: The camptothecins (CPTs) are potent radiosensitizers of malignant tumors in vivo. The extent of normal tissue damage after combined CPT and radiation treatment is unknown. In this article, a jejunal absorption assay with 99m Tc- pertechnetate (Na[ 99m TcO 4 ]) was used to assess C3H/Kam mice given total body irradiation (TBI) of 4 Gy, 6 Gy, and 8 Gy, 2 mg/kg single intramuscular injection of 9-AC or a combination of 2 mg/kg 9-AC + 4 Gy TBI. We also correlated the absorption data with morphologic changes in the jejunal mucosa. Materials and Methods: ( 99m TcO 4 ) - absorption from the intestinal lumen into the circulation was studied with dynamic γ-scintigraphy combined with a multichannel analyzer to record the radiometry data in a time-dependent fashion. Jejunal cross sections were scored for the number of cells per villus and the percentage of apoptotic and mitotic cells in the crypt compartment. The jejunal microcolony assay was used to quantify jejunal crypt survival. Results: A dose-dependent decrease in the absorption function was observed 3.5 days following TBI. The mean absorption rate was reduced to 89 ± 16% of control in response to a sublethal 4 Gy TBI and dropped to 47.5 (9.8% in response to 8 Gy TBI. The mean rate of intestinal absorption was delayed by single sublethal 2 mg/kg 9-AC injection to 62 (11% in comparison with control values. The combination of a single 4 Gy TBI with a 9-AC treatment decreased the ( 99m TcO 4 ) - jejunal absorption in an additive fashion producing absorption lifetime values more than twofold longer than controls. The decrease in ( 99m TcO 4 ) - absorption at 3.5 days after irradiation, 9-AC treatment or the combination of the two agents correlates with the number of cells per villus and the percentage of apoptotic cells in the crypt compartment. Conclusion: Dynamic enteroscintigraphy with 99m Tc-pertechnetate is a sensitive functional assay for rapid evaluation of radiation and chemotherapy induced intestinal

  1. Study of the effect of finite extent on sound transmission loss of single panel using a waveguide model

    OpenAIRE

    Prasetiyo , Iwan; Thompson , David

    2012-01-01

    International audience; The sound transmission loss (STL) of a panel is often estimated using an infinite plate model. However, some discrepancies are found between these predicted results and experimental ones. One of the sources of such discrepancies corresponds to the finite extent that is naturally found in real structures. In the present study an analytical waveguide model of sound transmission is used to study the effect of finite dimensions in one direction for a panel which is long in...

  2. Preconditioning of Antarctic maximum sea-ice extent by upper-ocean stratification on a seasonal timescale

    OpenAIRE

    Su, Zhan

    2017-01-01

    This study uses an observationally constrained and dynamically consistent ocean and sea ice state estimate. The author presents a remarkable agreement between the location of the edge of Antarctic maximum sea ice extent, reached in September, and the narrow transition band for the upper ocean (0–100 m depths) stratification, as early as April to June. To the south of this edge, the upper ocean has high stratification, which forbids convective fluxes to cross through; consequently, the ocean h...

  3. Principal forest dieback episodes in northern hardwoods: development of numeric indices of areal extent and severity

    International Nuclear Information System (INIS)

    Auclair, A.D.; Eglington, P.D.; Minnemeyer, S.L.

    1997-01-01

    The incidence of forest dieback in the Northern Hardwoods biome of Canada and the United States was determined for period from 1910 to 1990. Information from annual forest service pathology inventories in the two countries and other published literature was coded to estimate yearly the severity and areal extent of dieback on white/yellow birch and sugar maple from 1910 to 1990. Principal dieback episodes occurred as distinct waves coincident with maturation of the forest population in each of six regions. These episodes endured an average of 11 years. It is hypothesized that, once forest populations are mature, they are susceptible to extreme stresses such as freezing and drought which serve to synchronize the onset and subsidence of major dieback episodes. 38 refs., 5 figs., 5 tabs

  4. Dissolution of two NWCF calcines: Extent of dissolution and characterization of undissolved solids

    International Nuclear Information System (INIS)

    Brewer, K.N.; Herbst, R.S.; Tranter, T.J.

    1995-01-01

    A study was undertaken to determine the dissolution characteristics of two NWCF calcine types. A two-way blended calcine made from 4 parts nonradioactive aluminum nitrate and one part WM-102 was studied to determine the extent of dissolution for aluminum-type calcines. A two-way blend of 3.5 parts fluorinel waste from WM-187 and 1 part sodium waste from WM-185 was used to determine the extent of dissolution for zirconium-type calcines. This study was necessary to develop suitable aqueous separation flowsheets for the partitioning of actinides and fission products from ICPP calcines and to determine the disposition of the resulting undissolved solids (UDS). The dissolution flowsheet developed by Herbst was used to dissolve these two NWCF calcine types. Results show that greater than 95 wt% of aluminum and zirconium calcine types were dissolved after a single batch contact with 5 M HNO 3 . A characterization of the UDS indicates that the weight percent of TRU elements in the UDS resulting from both calcine type dissolutions increases by approximately an order of magnitude from their concentrations prior to dissolution. Substantial activities of cesium and strontium are also present in the UDS resulting from the dissolution of both calcine types. Multiple TRU, Cs, and Sr analyses of both UDS types show that these solids are relatively homogeneous. From this study, it is estimated that between 63.5 and 635 cubic meters of UDS will be generated from the dissolution of 3800 M 3 of calcine. The significant actinide and fission product activities in these UDS will preclude their disposal as low-level waste. If the actinide and fission activity resulting from the UDS is the only considered source in the dissolved calcine solutions, an estimated 99.9 to 99.99 percent of the solids must be removed from this solution for it to meet non-TRU Class A low-level waste

  5. Evaluation of nature and extent of injuries during Dahihandi festival.

    Science.gov (United States)

    Nemade, P; Wade, R; Patwardhan, A R; Kale, S

    2012-01-01

    Injuries related to the Hindu festival of Dahihandi where a human pyramid is formed and a pot of money kept at a height is broken, celebrated in the state of Maharashtra, have seen a significant rise in the past few years. The human pyramid formed is multi-layered and carries with it a high risk of injury including mortality. To evaluate the nature, extent and influencing factors of injuries related to Dahihandi festival. We present a retrospective analysis of patients who presented in a tertiary care center with injuries during the Dahihandi festival in the year 2010. 124 patients' records were evaluated for timing of injury, height of the Dahihandi pyramid, position of the patient in the multi-layered pyramid, mode of pyramid collapse and mechanism of an injury. A binary regression logistic analysis for risk factors was done at 5% significance level. Univariate and multi-variate binary logistic regression of the risk factors for occurrence of a major or minor injury was done using Minitab™ version 16.0 at 5% significance. Out of 139 patients presented to the center, 15 were not involved directly in the formation of pyramid, rest 124 were included in the analysis. A majority of the patients were above 15 years of age [110 (83.6%)]. 46 (37.1%) patients suffered major injuries. There were 39 fractures, 3 cases of chest wall trauma with 10 cases of head injuries and 1 death. More than half of the patients [78 (56.1%)] were injured after 1800 hours. 73 (58.9%) injured participants were part of the pyramid constructed to reach the Dahihandi placed at 30 feet or more above the ground. 72 (51.8%) participants were part of the middle layers of the pyramid. Fall of a participant from upstream layers on the body was the main mechanism of injury, and majority [101 (81.5%)] of the patients suffered injury during descent phase of the pyramid. There is a considerable risk of serious, life-threatening injuries inherent to human pyramid formation and descent in the Dahihandi

  6. Geographic extent and variation of a coral reef trophic cascade.

    Science.gov (United States)

    McClanahan, T R; Muthiga, N A

    2016-07-01

    Trophic cascades caused by a reduction in predators of sea urchins have been reported in Indian Ocean and Caribbean coral reefs. Previous studies have been constrained by their site-specific nature and limited spatial replication, which has produced site and species-specific understanding that can potentially preclude larger community-organization nuances and generalizations. In this study, we aimed to evaluate the extent and variability of the cascade community in response to fishing across ~23° of latitude and longitude in coral reefs in the southwestern Indian Ocean. The taxonomic composition of predators of sea urchins, the sea urchin community itself, and potential effects of changing grazer abundance on the calcifying benthic organisms were studied in 171 unique coral reef sites. We found that geography and habitat were less important than the predator-prey relationships. There were seven sea urchin community clusters that aligned with a gradient of declining fishable biomass and the abundance of a key predator, the orange-lined triggerfish (Balistapus undulatus). The orange-lined triggerfish dominated where sea urchin numbers and diversity were low but the relative abundance of wrasses and emperors increased where sea urchin numbers were high. Two-thirds of the study sites had high sea urchin biomass (>2,300 kg/ha) and could be dominated by four different sea urchin species, Echinothrix diadema, Diadema savignyi, D. setosum, and Echinometra mathaei, depending on the community of sea urchin predators, geographic location, and water depth. One-third of the sites had low sea urchin biomass and diversity and were typified by high fish biomass, predators of sea urchins, and herbivore abundance, representing lightly fished communities with generally higher cover of calcifying algae. Calcifying algal cover was associated with low urchin abundance where as noncalcifying fleshy algal cover was not clearly associated with herbivore abundance. Fishing of the orange

  7. Current extent and stratification of agroforestry in the European Union

    DEFF Research Database (Denmark)

    den Herder, Michael; Moreno, Gerardo; Mosquera-Losada, Rosa M.

    2017-01-01

    in the European Union. We classified agroforestry into three main types of agroforestry systems: arable agroforestry, livestock agroforestry and high value tree agroforestry. These three classes are partly overlapping as high value tree agroforestry can be part of either arable or livestock agroforestry....... Agroforestry areas were mapped using LUCAS Land Use and Land Cover data (Eurostat, 2015). By identifying certain combinations of primary and secondary land cover and/or land management it was possible to identify agroforestry points and stratify them in the three different systems. According to our estimate...... the largest area. High value tree agroforestry and arable agroforestry cover 1.1 and 0.3 million ha respectively. Spain (5.6 million ha), France (1.6 million ha), Greece (1.6 million ha), Italy (1.4 million ha), Portugal (1.2 million ha), Romania (0.9 million ha) and Bulgaria (0.9 million ha) have the largest...

  8. Food price seasonality in Africa: Measurement and extent.

    Science.gov (United States)

    Gilbert, Christopher L; Christiaensen, Luc; Kaminski, Jonathan

    2017-02-01

    Everyone knows about seasonality. But what exactly do we know? This study systematically measures seasonal price gaps at 193 markets for 13 food commodities in seven African countries. It shows that the commonly used dummy variable or moving average deviation methods to estimate the seasonal gap can yield substantial upward bias. This can be partially circumvented using trigonometric and sawtooth models, which are more parsimonious. Among staple crops, seasonality is highest for maize (33 percent on average) and lowest for rice (16½ percent). This is two and a half to three times larger than in the international reference markets. Seasonality varies substantially across market places but maize is the only crop in which there are important systematic country effects. Malawi, where maize is the main staple, emerges as exhibiting the most acute seasonal differences. Reaching the Sustainable Development Goal of Zero Hunger requires renewed policy attention to seasonality in food prices and consumption.

  9. Field measurement of albedo for limited extent test surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Sailor, David J. [Portland State University, Department of Mechanical and Materials Engineering, P.O. Box 751-ME, Portland, OR 97207 (United States); Resh, Kyle; Segura, Del [Tulane University, Department of Mechanical Engineering, 400 Lindy Boggs Center, New Orleans, LA 70118 (United States)

    2006-05-15

    A new method is introduced for field measurement of surface albedo. This method consists of the use of a cylindrical shade ring made of opaque fabric with a known (low) albedo placed over a test surface. The albedo measurement is accomplished using two small pyranometers situated so that the downward-facing pyranometer receives radiation only from the test surface and the shade ring. The upward-facing pyranometer simultaneously records the incoming solar radiation. The radiation received by the downward-facing pyramometer is a combination of reflected radiation from shaded and unshaded portions of these two surfaces, requiring detailed accounting of the resulting view factor geometries. The method presented here improves upon past approaches by allowing for smaller sample sizes, minimizing errors associated with reflective properties of the surroundings, and allowing for accurate measurements even under partially cloudy skies. In addition to these methodological improvements we introduce an approach for estimating the uncertainty in the resulting albedo measurements. Results from field measurements are presented to validate the measurement protocol, and to compare its accuracy with the accuracy of a published standard. (author)

  10. To what extent can ecosystem services motivate protecting biodiversity?

    Science.gov (United States)

    Dee, Laura E; De Lara, Michel; Costello, Christopher; Gaines, Steven D

    2017-08-01

    Society increasingly focuses on managing nature for the services it provides people rather than for the existence of particular species. How much biodiversity protection would result from this modified focus? Although biodiversity contributes to ecosystem services, the details of which species are critical, and whether they will go functionally extinct in the future, are fraught with uncertainty. Explicitly considering this uncertainty, we develop an analytical framework to determine how much biodiversity protection would arise solely from optimising net value from an ecosystem service. Using stochastic dynamic programming, we find that protecting a threshold number of species is optimal, and uncertainty surrounding how biodiversity produces services makes it optimal to protect more species than are presumed critical. We define conditions under which the economically optimal protection strategy is to protect all species, no species, and cases in between. We show how the optimal number of species to protect depends upon different relationships between species and services, including considering multiple services. Our analysis provides simple criteria to evaluate when managing for particular ecosystem services could warrant protecting all species, given uncertainty. Evaluating this criterion with empirical estimates from different ecosystems suggests that optimising some services will be more likely to protect most species than others. © 2017 John Wiley & Sons Ltd/CNRS.

  11. Extent of late gadolinium enhancement at right ventricular insertion points in patients with hypertrophic cardiomyopathy: relation with diastolic dysfunction

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Yinsu [Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of); The First Affiliated Hospital of Nanjing Medical University, Department of Radiology, Nanjing, Jiangsu (China); Park, Eun-Ah; Lee, Whal; Chu, Ajung; Chung, Jin Wook; Park, Jae Hyung [Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of); Kim, Hyung-Kwan [Seoul National University Hospital, Division of Cardiology, Department of Internal Medicine, Seoul (Korea, Republic of)

    2015-04-01

    Our aim was to examine the association between the extent of late gadolinium enhancement (LGE) at right ventricular insertion points (RVIP) and left ventricular (LV) functional parameters in patients with hypertrophic cardiomyopathy (HCM). Sixty-one HCM patients underwent echocardiography and cardiovascular magnetic resonance (CMR) within one week. Mitral annular velocities (E/E') were obtained from echocardiography; LV ejection fraction (EF), LV mass index, LV wall maximal thickness, and left atrial volume index (LAVI) were obtained from MR. LGE extent was quantified (proportion of total LV myocardial mass) according to location: % RVIP-LGE and % non-RVIP-LGE. Although LGE was commonly present in both apical (74 %) and non-apical HCMs (88 %) (p = 0.163), RVIP-LGE was more frequent (86 % vs. 47 %, p = 0.002) in non-apical HCMs in which E/E' was significantly higher (19.23 ± 8.40 vs. 13.13 ± 5.06, p = 0.009). In addition, RVIP-LGE extent was associated with LV diastolic dysfunction (r = 0.45, p < 0.001 for E/E'; r = 0.53, p < 0.001 for LAVI) and lower LVEF (r = -0.42, p = 0.001). There was no correlation between non-RVIP-LGE extent and other parameters. Multiple linear regression analysis revealed RVIP-LGE extent as an independent predictor of E/E' (β = 0.45, p < 0.001) and LAVI in HCM patients (β = 0.53, p < 0.001). The extent of LGE at RVIPs in HCM patients is associated with increased estimated LV filling pressure and chronic diastolic burden. (orig.)

  12. Soil-water salinity pollution: extent, management and potential impacts on agricultural sustain ability

    International Nuclear Information System (INIS)

    Javid, M.A.; Ali, K.; Javed, M.; Mahmood, A.

    1999-01-01

    One of the significant environmental hazards of irrigated agriculture is the accumulation of salts in the soil. The presence of large quantities of certain soluble salts badly affects the physical, chemical, biological and fertility characteristics of the soils. This pollution of soil salinity and its toxic degradation directly affects plants, hence impacting the air filters of nature. The soil and water salinity has adversely reduced the yield of our major agricultural crops to an extent that agricultural sustainability is being threatened. Salinity has also dwindled the survival of marine life, livestock, in addition to damaging of construction works. The problem can be estimated from the fact that out of 16.2 m.ha of irrigated land of Pakistan, 6.3 . ha are salt affected in the Indus Plain. The state of water pollution can further be assessed from the fact that presently about 106 MAF of water is diverted from the rivers into the canals of the Indus Plain which contains 28 MT of salts. Due to soil and water pollution more than 40,000 ha of good irrigated land goes out of cultivation every year. This it has drastically reduced the potential of our agricultural lands. Hence, an estimated annual loss of Rs. 14,000 million has been reported due to this soil-water salinity pollution in Pakistan. Some management options to mitigate the soil - water salinity pollution are proposed. (author)

  13. Variability and Trends in Sea Ice Extent and Ice Production in the Ross Sea

    Science.gov (United States)

    Comiso, Josefino; Kwok, Ronald; Martin, Seelye; Gordon, Arnold L.

    2011-01-01

    Salt release during sea ice formation in the Ross Sea coastal regions is regarded as a primary forcing for the regional generation of Antarctic Bottom Water. Passive microwave data from November 1978 through 2008 are used to examine the detailed seasonal and interannual characteristics of the sea ice cover of the Ross Sea and the adjacent Bellingshausen and Amundsen seas. For this period the sea ice extent in the Ross Sea shows the greatest increase of all the Antarctic seas. Variability in the ice cover in these regions is linked to changes in the Southern Annular Mode and secondarily to the Antarctic Circumpolar Wave. Over the Ross Sea shelf, analysis of sea ice drift data from 1992 to 2008 yields a positive rate of increase in the net ice export of about 30,000 sq km/yr. For a characteristic ice thickness of 0.6 m, this yields a volume transport of about 20 cu km/yr, which is almost identical, within error bars, to our estimate of the trend in ice production. The increase in brine rejection in the Ross Shelf Polynya associated with the estimated increase with the ice production, however, is not consistent with the reported Ross Sea salinity decrease. The locally generated sea ice enhancement of Ross Sea salinity may be offset by an increase of relatively low salinity of the water advected into the region from the Amundsen Sea, a consequence of increased precipitation and regional glacial ice melt.

  14. Extent, trends, and perpetrators of prostitution-related homicide in the United States.

    Science.gov (United States)

    Brewer, Devon D; Dudek, Jonathan A; Potterat, John J; Muth, Stephen Q; Roberts, John M; Woodhouse, Donald E

    2006-09-01

    Prostitute women have the highest homicide victimization rate of any set of women ever studied. We analyzed nine diverse homicide data sets to examine the extent, trends, and perpetrators of prostitution-related homicide in the United States. Most data sources substantially under-ascertained prostitute homicides. As estimated from a conservative capture-recapture analysis, 2.7% of female homicide victims in the United States between 1982 and 2000 were prostitutes. Frequencies of recorded prostitute and client homicides increased substantially in the late 1980s and early 1990s; nearly all of the few observed pimp homicides occurred before the late 1980s. These trends may be linked to the rise of crack cocaine use. Prostitutes were killed primarily by clients, clients were killed mainly by prostitutes, and pimps were killed predominantly by pimps. Another conservative estimate suggests that serial killers accounted for 35% of prostitute homicides. Proactive surveillance of, and evidence collection from, clients and prostitutes might enhance the investigation of prostitution-related homicide.

  15. Midbrain morphology reflects extent of brain damage in Krabbe disease

    Energy Technology Data Exchange (ETDEWEB)

    Zuccoli, Giulio; Narayanan, Srikala; Panigrahy, Ashok [Children' s Hospital of Pittsburgh of University of Pittsburgh Medical Center, Section of Neuroradiology, Pittsburgh, PA (United States); Poe, Michele D.; Escolar, Maria L. [University of Pittsburgh, Program for the Study of Neurodevelopment in Rare Disorders, Children' s Hospital of Pittsburgh of University of Pittsburgh Medical Center, Pittsburgh, PA (United States)

    2015-07-15

    To study the relationships between midbrain morphology, Loes score, gross motor function, and cognitive function in infantile Krabbe disease. Magnetic resonance imaging (MRI) scans were evaluated by two neuroradiologists blinded to clinical status and neurodevelopmental function of children with early or late infantile Krabbe disease. A simplified qualitative 3-point scoring system based on midbrain morphology on midsagittal MRI was used. A score of 0 represented normal convex morphology of the midbrain, a score of 1 represented flattening of the midbrain, and a score of 3 represented concave morphology of the midbrain (hummingbird sign). Spearman correlations were estimated between this simplified MRI scoring system and the Loes score, gross motor score, and cognitive score. Forty-two MRIs of 27 subjects were reviewed. Analysis of the 42 scans showed normal midbrain morphology in 3 (7.1 %) scans, midbrain flattening in 11 (26.2 %) scans, and concave midbrain morphology (hummingbird sign) in 28 (66.7 %) scans. Midbrain morphology scores were positively correlated with the Loes score (r = 0.81, p < 0.001) and negatively correlated with both gross motor and cognitive scores (r = -.84, p < 0.001; r = -0.87, p < 0.001, respectively). The inter-rater reliability for the midbrain morphology scale was κ =.95 (95 % CI: 0.86-1.0), and the inter-rater reliability for the Loes scale was κ =.58 (95 % CI: 0.42-0.73). Midbrain morphology scores of midsagittal MRI images correlates with cognition and gross motor function in children with Krabbe disease. This MRI scoring system represents a simple but reliable method to assess disease progression in patients with infantile Krabbe disease. (orig.)

  16. Midbrain morphology reflects extent of brain damage in Krabbe disease

    International Nuclear Information System (INIS)

    Zuccoli, Giulio; Narayanan, Srikala; Panigrahy, Ashok; Poe, Michele D.; Escolar, Maria L.

    2015-01-01

    To study the relationships between midbrain morphology, Loes score, gross motor function, and cognitive function in infantile Krabbe disease. Magnetic resonance imaging (MRI) scans were evaluated by two neuroradiologists blinded to clinical status and neurodevelopmental function of children with early or late infantile Krabbe disease. A simplified qualitative 3-point scoring system based on midbrain morphology on midsagittal MRI was used. A score of 0 represented normal convex morphology of the midbrain, a score of 1 represented flattening of the midbrain, and a score of 3 represented concave morphology of the midbrain (hummingbird sign). Spearman correlations were estimated between this simplified MRI scoring system and the Loes score, gross motor score, and cognitive score. Forty-two MRIs of 27 subjects were reviewed. Analysis of the 42 scans showed normal midbrain morphology in 3 (7.1 %) scans, midbrain flattening in 11 (26.2 %) scans, and concave midbrain morphology (hummingbird sign) in 28 (66.7 %) scans. Midbrain morphology scores were positively correlated with the Loes score (r = 0.81, p < 0.001) and negatively correlated with both gross motor and cognitive scores (r = -.84, p < 0.001; r = -0.87, p < 0.001, respectively). The inter-rater reliability for the midbrain morphology scale was κ =.95 (95 % CI: 0.86-1.0), and the inter-rater reliability for the Loes scale was κ =.58 (95 % CI: 0.42-0.73). Midbrain morphology scores of midsagittal MRI images correlates with cognition and gross motor function in children with Krabbe disease. This MRI scoring system represents a simple but reliable method to assess disease progression in patients with infantile Krabbe disease. (orig.)

  17. Association of myocardial inotropic reserve and adrenergic nerve alterations in idiopathic dilated cardiomyopathy. A dobutamine stress echocardiographic and 123-I-MIBG scintigraphic study

    International Nuclear Information System (INIS)

    Prassopoulos, V.P.; Koukouraki, S.; Velidaki, A.; Karkavitsas, N.; Parthenakis, F.; Patrianakos, A.; Kochiadakis, G.; Papadimitriou, E.; Vardas, P.

    2002-01-01

    Aim: Evaluation of contractile reserve is important in congestive hear failure. The aim of this study was to examine the relationship between the myocardial response to dobutamine by stress echocardiography and the sympathetic nerve alterations by 123-I-Metaiodobenzylguanidine (MIBG)scintigraphy and how both contribute to predict exercise capacity in patients with idiopathic dilated cardiomyopathy. Materials-Methods: We studied 20 patients with idiopathic dilated cardiomyopathy (IDC) and ejection fraction < 45% (M/F 13/7, age 56±11 years) while 15 healthy individuals served as controls. Echocardiography and myocardial scintigraphic study with 123-I- MIBG, provided quantitative assessment of left ventricular (LV) wall motion and heart to mediastinum uptake(H/M) ratio and washout. All patients underwent a cardiopulmonary exercise test with a modified Naughton protocol and gas exchange data were analyzed. According to LV response to dobutamine, patients were divided into two groups: those in whom contractility improved in ≥ five segments (Group I: 11 patients) and those in whom contractility improved in < 5 segments (Group II : 9 patients). Results: MIBG uptake was significantly lower in patients than in controls (p < 0.001). MIBG uptake and washout was higher in Group I compared to Group II (P<0,01 and p<0,05). Late MIBG H/M was correlated with resting ejection fraction (r=0,70), wall motion score index (WMSI) (r=-0,50), end systolic wall stress (r=-0,61), washout (r=-0,57), and oxygen consumption at peak exercise (r=0,64) and at anaerobic threshold (r=0,67). LV ejection fraction increased in both groups at Dobutamine, with a higher increase in Group I (p=0,008). WMSI changes at dobutamine correlated significantly with resting ejection fraction (r=0,46) early (r=0,53) and late (r=0,54) MIBG. Multivariate analysis revealed that only the late MIBG uptake was independently associated with the improvement in WMSI. Conclusions: The present data indicate that in

  18. Structure of Exhausts in Magnetic Reconnection with an X-line of Finite Extent

    Energy Technology Data Exchange (ETDEWEB)

    Shepherd, L. S.; Cassak, P. A. [Department of Physics and Astronomy, West Virginia University, Morgantown, WV 26506 (United States); Drake, J. F. [Department of Physics and the Institute for Physical Science and Technology and the Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, MD 20742 (United States); Gosling, J. T. [Laboratory for Atmospheric and Space Physics, University of Colorado at Boulder, Boulder, CO 80303 (United States); Phan, T.-D. [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Shay, M. A. [Bartol Research Institute, Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States)

    2017-10-20

    We present quantitative predictions of the structure of reconnection exhausts in three-dimensional magnetic reconnection with an X-line of finite extent in the out-of-plane direction. Sasunov et al. showed that they have a tilted ribbon-like shape bounded by rotational discontinuities and tangential discontinuities. We show analytically and numerically that this prediction is largely correct. When there is an out-of-plane (guide) magnetic field, the presence of the upstream field that does not reconnect acts as a boundary condition in the normal direction, which forces the normal magnetic field to be zero outside the exhaust. This condition constrains the normal magnetic field inside the exhaust to be small. Thus, rather than the ribbon tilting in the inflow direction, the exhaust remains collimated in the normal direction and is forced to expand nearly completely in the out-of-plane direction. This exhaust structure is in stark contrast to the two-dimensional picture of reconnection, where reconnected flux expands in the normal direction. We present analytical predictions for the structure of the exhausts in terms of upstream conditions. The predictions are confirmed using three-dimensional resistive-magnetohydrodynamic simulations with a finite-length X-line achieved using a localized (anomalous) resistivity. Implications to reconnection in the solar wind are discussed. In particular, the results can be used to estimate a lower bound for the extent of the X-line in the out-of-plane direction solely using single-spacecraft data taken downstream in the exhausts.

  19. Structure of Exhausts in Magnetic Reconnection with an X-line of Finite Extent

    International Nuclear Information System (INIS)

    Shepherd, L. S.; Cassak, P. A.; Drake, J. F.; Gosling, J. T.; Phan, T.-D.; Shay, M. A.

    2017-01-01

    We present quantitative predictions of the structure of reconnection exhausts in three-dimensional magnetic reconnection with an X-line of finite extent in the out-of-plane direction. Sasunov et al. showed that they have a tilted ribbon-like shape bounded by rotational discontinuities and tangential discontinuities. We show analytically and numerically that this prediction is largely correct. When there is an out-of-plane (guide) magnetic field, the presence of the upstream field that does not reconnect acts as a boundary condition in the normal direction, which forces the normal magnetic field to be zero outside the exhaust. This condition constrains the normal magnetic field inside the exhaust to be small. Thus, rather than the ribbon tilting in the inflow direction, the exhaust remains collimated in the normal direction and is forced to expand nearly completely in the out-of-plane direction. This exhaust structure is in stark contrast to the two-dimensional picture of reconnection, where reconnected flux expands in the normal direction. We present analytical predictions for the structure of the exhausts in terms of upstream conditions. The predictions are confirmed using three-dimensional resistive-magnetohydrodynamic simulations with a finite-length X-line achieved using a localized (anomalous) resistivity. Implications to reconnection in the solar wind are discussed. In particular, the results can be used to estimate a lower bound for the extent of the X-line in the out-of-plane direction solely using single-spacecraft data taken downstream in the exhausts.

  20. Assessing the extent and diversity of riparian ecosystems in Sonora, Mexico

    Science.gov (United States)

    Scott, M.L.; Nagler, P.L.; Glenn, E.P.; Valdes-Casillas, C.; Erker, J.A.; Reynolds, E.W.; Shafroth, P.B.; Gomez-Limon, E.; Jones, C.L.

    2009-01-01

    Conservation of forested riparian ecosystems is of international concern. Relatively little is known of the structure, composition, diversity, and extent of riparian ecosystems in Mexico. We used high- and low-resolution satellite imagery from 2000 to 2006, and ground-based sampling in 2006, to assess the spatial pattern, extent, and woody plant composition of riparian forests across a range of spatial scales for the state of Sonora, Mexico. For all 3rd and higher order streams, river bottomlands with riparian forests occupied a total area of 2,301 km2. Where forested bottomlands remained, on average, 34% of the area had been converted to agriculture while 39% remained forested. We estimated that the total area of riparian forest along the principal streams was 897 km2. Including fencerow trees, the total forested riparian area was 944 km2, or 0.5% of the total land area of Sonora. Ground-based sampling of woody riparian vegetation consisted of 92, 50 m radius circular plots. About 79 woody plant species were noted. The most important tree species, based on cover and frequency, were willow species Salix spp. (primarily S. goodingii and S. bonplandiana), mesquite species Prosopis spp. (primarily P. velutina), and Fremont cottonwood Populus fremontii. Woody riparian taxa at the reach scale showed a trend of increasing diversity from north to south within Sonora. Species richness was greatest in the willow-bald cypress Taxodium distichum var. mexicanum-Mexican cottonwood P. mexicana subsp. dimorphia ecosystem. The non-native tamarisk Tamarix spp. was rare, occurring at just three study reaches. Relatively natural stream flow patterns and fluvial disturbance regimes likely limit its establishment and spread. ?? 2008 Springer Science + Business Media BV.

  1. Hydrologic impacts of changes in climate and glacier extent in the Gulf of Alaska watershed

    Science.gov (United States)

    Beamer, J. P.; Hill, D. F.; McGrath, D.; Arendt, A.; Kienholz, C.

    2017-09-01

    High-resolution regional-scale hydrologic models were used to quantify the response of late 21st century runoff from the Gulf of Alaska (GOA) watershed to changes in regional climate and glacier extent. NCEP Climate Forecast System Reanalysis data were combined with five Coupled Model Intercomparison Project Phase 5 general circulation models (GCMs) for two representative concentration pathway (RCP) scenarios (4.5 and 8.5) to develop meteorological forcing for the period 2070-2099. A hypsographic model was used to estimate future glacier extent given assumed equilibrium line altitude (ELA) increases of 200 and 400 m. GCM predictions show an increase in annual precipitation of 12% for RCP 4.5 and 21% for RCP 8.5, and an increase in annual temperature of 2.5°C for RCP 4.5 and 4.3°C for RCP 8.5, averaged across the GOA. Scenarios with perturbed climate and glaciers predict annual GOA-wide runoff to increase by 9% for RCP4.5/ELA200 case and 14% for the RCP8.5/ELA400 case. The glacier runoff decreased by 14% for RCP4.5/ELA200 and by 34% for the RCP8.5/ELA400 case. Intermodel variability in annual runoff was found to be approximately twice the variability in precipitation input. Additionally, there are significant changes in runoff partitioning and increases in snowpack runoff are dominated by increases in rain-on-snow events. We present results aggregated across the entire GOA and also for individual watersheds to illustrate the range in hydrologic regime changes and explore the sensitivities of these results by independently perturbing only climate forcings and only glacier cover.

  2. An essay on the extent and significance of the Greek athletic culture in the classical period

    DEFF Research Database (Denmark)

    Nielsen, Thomas Heine

    2014-01-01

    This article discusses the extent of the Greek athletic culture in the classical period. It is demonstrated that the athletic culture had a surprising extent, and the article goes on the discuss the historical significance of this fact.......This article discusses the extent of the Greek athletic culture in the classical period. It is demonstrated that the athletic culture had a surprising extent, and the article goes on the discuss the historical significance of this fact....

  3. Extent estimation of different factors influence on the corrosion cracking of steels type X18H10T in NPP

    International Nuclear Information System (INIS)

    Stjazhkin, P.S.; Kritski, V.G.; Simanovski, V.M.; Kovalev, S.M.; Malov, M.Ju.; Butorin, S.L.

    2002-01-01

    1. Results of the performed complex study of chemical and physical factors effect on pipelines DU-300 integrity proves that in HT and going to power conditions under reactor RBMK-1000 operation there are most favourable conditions for origin and further undergrowth of crack in near-joint zones of pipelines and equipment made of steel X18H10T. These conditions are defined by high concentration of oxygen and electric conductivity of the coolant, higher in comparison with NOC (operation at power) stressed-and-strained state of units being loaded with additional dynamic loads. 2. Results received are of an evaluating character, they show only that under start-up operations after thermal shutdown an accelerated growth of cracks is most probable. 3. In view of a general trend of prolongation of operation terms of NPP with RBMK-1000 (LNPP including), realization of procedures to decrease probability of occurrence and evolution of CCS in equipment and pipelines and introduction of a system of corrosion monitoring is one of the actual tasks. 4. An additional measure can be a validated transition to hydro-pressing of the circuit at lower temperature (80-90 C). (authors)

  4. Estimating Common Growth Patterns in Juvenile Chinook Salmon (Oncorhynchus tshawytscha from Diverse Genetic Stocks and a Large Spatial Extent.

    Directory of Open Access Journals (Sweden)

    Pascale A L Goertler

    Full Text Available Life history variation in Pacific salmon (Oncorhynchus spp. supports species resilience to natural disturbances and fishery exploitation. Within salmon species, life-history variation often manifests during freshwater and estuarine rearing, as variation in growth. To date, however, characterizing variability in growth patterns within and among individuals has been difficult via conventional sampling methods because of the inability to obtain repeated size measurements. In this study we related otolith microstructures to growth rates of individual juvenile Chinook salmon (O. tshawytscha from the Columbia River estuary over a two-year period (2010-2012. We used dynamic factor analysis to determine whether there were common patterns in growth rates within juveniles based on their natal region, capture location habitat type, and whether they were wild or of hatchery origin. We identified up to five large-scale trends in juvenile growth rates depending on month and year of capture. We also found that hatchery fish had a narrower range of trend loadings for some capture groups, suggesting that hatchery fish do not express the same breadth of growth variability as wild fish. However, we were unable to resolve a relationship between specific growth patterns and habitat transitions. Our study exemplifies how a relatively new statistical analysis can be applied to dating or aging techniques to summarize individual variation, and characterize aspects of life history diversity.

  5. Multi-parameter crack tip stress state description for estimation of fracture process zone extent in silicate composite WST specimens

    Czech Academy of Sciences Publication Activity Database

    Veselý, V.; Sobek, J.; Šestáková, L.; Frantík, P.; Seitl, Stanislav

    2013-01-01

    Roč. 7, č. 25 (2013), s. 69-78 ISSN 1971-8993 R&D Projects: GA ČR(CZ) GAP104/11/0833; GA ČR(CZ) GAP105/11/1551 Institutional support: RVO:68081723 Keywords : Near-crack tip fields * Williams series * higher-order terms * stress field approximation * wedge splitting test * fracture process zone Subject RIV: JL - Materials Fatigue, Friction Mechanics

  6. To what extent is blood a reasonable surrogate for brain in gene expression studies: estimation from mouse hippocampus and spleen

    Directory of Open Access Journals (Sweden)

    Matthew N Davies

    2009-10-01

    Full Text Available Microarrays are designed to measure genome-wide differences in gene expression. In cases where a tissue is not accessible for analysis (e.g. human brain, it is of interest to determine whether a second, accessible tissue could be used as a surrogate for transcription profiling. Surrogacy has applications in the study of behavioural and neurodegenerative disorders. Comparison between hippocampus and spleen mRNA obtained from a mouse recombinant inbred panel indicates a high degree of correlation between the tissues for genes that display a high heritability of expression level. This correlation is not limited to apparent expression differences caused by sequence polymorphisms in the target sequences and includes both cis and trans genetic effects. A tissue such as blood could therefore give surrogate information on expression in brain for a subset of genes, in particular those co-expressed between the two tissues, which have heritably varying expression.

  7. Estimations of the extent of migration of surficially applied water for various surface conditions near the potential repository perimeter

    International Nuclear Information System (INIS)

    Sobolik, S.R.; Fewell, M.E.

    1993-12-01

    The Yucca Mountain Site Characterization Project is studying Yucca Mountain in southwestern Nevada as a potential site for a high-level nuclear waste repository. Site characterization includes surface-based and underground testing. Analyses have been performed to support the design of site characterization activities so to have minimal impact on the ability of the site to isolate waste, and on tests performed as part of the characterization process. Two examples of site characterization activities are the construction of an Exploratory Studies Facility, which may include underground shafts, drifts, and ramps, and surface-based testing activities, which may require borehole drilling, excavation of test pits, and road watering for dust control. The information in this report pertains to two-dimensional numerical calculations modeling the movement of surficially applied water and the potential effects of that water on repository performance and underground experiments. This document contains information that has been used in preparing recommendations for two Yucca Mountain Site Characterization Project documents: Appendix I of the Exploratory Studies Facility Design Requirements document, and the Surface-Based Testing Field Requirements Document

  8. Age, extent and carbon storage of the central Congo Basin peatland complex.

    Science.gov (United States)

    Dargie, Greta C; Lewis, Simon L; Lawson, Ian T; Mitchard, Edward T A; Page, Susan E; Bocko, Yannick E; Ifo, Suspense A

    2017-02-02

    Peatlands are carbon-rich ecosystems that cover just three per cent of Earth's land surface, but store one-third of soil carbon. Peat soils are formed by the build-up of partially decomposed organic matter under waterlogged anoxic conditions. Most peat is found in cool climatic regions where unimpeded decomposition is slower, but deposits are also found under some tropical swamp forests. Here we present field measurements from one of the world's most extensive regions of swamp forest, the Cuvette Centrale depression in the central Congo Basin. We find extensive peat deposits beneath the swamp forest vegetation (peat defined as material with an organic matter content of at least 65 per cent to a depth of at least 0.3 metres). Radiocarbon dates indicate that peat began accumulating from about 10,600 years ago, coincident with the onset of more humid conditions in central Africa at the beginning of the Holocene. The peatlands occupy large interfluvial basins, and seem to be largely rain-fed and ombrotrophic-like (of low nutrient status) systems. Although the peat layer is relatively shallow (with a maximum depth of 5.9 metres and a median depth of 2.0 metres), by combining in situ and remotely sensed data, we estimate the area of peat to be approximately 145,500 square kilometres (95 per cent confidence interval of 131,900-156,400 square kilometres), making the Cuvette Centrale the most extensive peatland complex in the tropics. This area is more than five times the maximum possible area reported for the Congo Basin in a recent synthesis of pantropical peat extent. We estimate that the peatlands store approximately 30.6 petagrams (30.6 × 10 15  grams) of carbon belowground (95 per cent confidence interval of 6.3-46.8 petagrams of carbon)-a quantity that is similar to the above-ground carbon stocks of the tropical forests of the entire Congo Basin. Our result for the Cuvette Centrale increases the best estimate of global tropical peatland carbon stocks by

  9. Mapping Daily and Maximum Flood Extents at 90-m Resolution During Hurricanes Harvey and Irma Using Passive Microwave Remote Sensing

    Science.gov (United States)

    Galantowicz, J. F.; Picton, J.; Root, B.

    2017-12-01

    Passive microwave remote sensing can provided a distinct perspective on flood events by virtue of wide sensor fields of view, frequent observations from multiple satellites, and sensitivity through clouds and vegetation. During Hurricanes Harvey and Irma, we used AMSR2 (Advanced Microwave Scanning Radiometer 2, JAXA) data to map flood extents starting from the first post-storm rain-free sensor passes. Our standard flood mapping algorithm (FloodScan) derives flooded fraction from 22-km microwave data (AMSR2 or NASA's GMI) in near real time and downscales it to 90-m resolution using a database built from topography, hydrology, and Global Surface Water Explorer data and normalized to microwave data footprint shapes. During Harvey and Irma we tested experimental versions of the algorithm designed to map the maximum post-storm flood extent rapidly and made a variety of map products available immediately for use in storm monitoring and response. The maps have several unique features including spanning the entire storm-affected area and providing multiple post-storm updates as flood water shifted and receded. From the daily maps we derived secondary products such as flood duration, maximum flood extent (Figure 1), and flood depth. In this presentation, we describe flood extent evolution, maximum extent, and local details as detected by the FloodScan algorithm in the wake of Harvey and Irma. We compare FloodScan results to other available flood mapping resources, note observed shortcomings, and describe improvements made in response. We also discuss how best-estimate maps could be updated in near real time by merging FloodScan products and data from other remote sensing systems and hydrological models.

  10. Scintigraphic picture in Gaucher's disease

    International Nuclear Information System (INIS)

    Bykov, S.A.; Gafton, G.I.; Petrov, V.P.

    1988-01-01

    Analysis of the results of combined radionuclide investigation of the liver, spleen, kidney, lymph nodes and bones in a patient with Gaucher's disease is given. Scintigraphy was shown to be an important method for making correct diagnosis in patients with this rare disease

  11. Scintigraphic findings in Gaucher's disease

    International Nuclear Information System (INIS)

    Israel, O.; Jerushalmi, J.; Front, D.

    1986-01-01

    Gaucher's disease involves the liver, the spleen, and the bone. Liver-spleen and bone scintigraphy were used during an 8-yr period to evaluate changes caused by this disease. Patients were investigated with a liver-spleen scan for abdominal pain, mechanical discomfort, enlarged liver or spleen on physical examination, abdominal mass, abnormal liver function tests, and symptoms of hypersplenism. Fourteen liver-spleen scans were performed in nine patients. Liver scintigraphy showed various degrees of enlargement and inhomogeneous uptake. In two patients focal defects were detected. In one, focal defects were due to liver involvement with Gaucher's disease, but in the other they were caused by metastatic pancreatic carcinoma. The study was also useful in detecting splenic infarction and in following enlargement of the spleen after partial splenectomy. The main indication for bone scintigraphy in six patients was bone pain. This was found to be caused by either aseptic necrosis of the head of the femur, bone infarction, pathological fractures, or osteomyelitis. Loosening after total hip replacement was ruled out in three patients and missed in one patient. Scintigraphy appears to be a simple, sensitive test for evaluation of the liver, spleen, and bony skeleton in patients with symptomatic Gaucher's disease

  12. Scintigraphic appearance of Alzheimer diesase

    International Nuclear Information System (INIS)

    Holman, B.L.; Johnson, K.A.

    1991-01-01

    Alzheimer disease (AD) is a devastating affliction of the elderly that has reached epidemic proportions. It produces regional abnormalities of brain blood flow and metabolism that may have diagnostic utility. In this paper the author determine the predictive value of Tc-99m HMPAO SPECT for detecting AD based on the prospective study of 132 consecutive patients coming to their nuclear medicine clinical unit for evaluation of memory loss or cognitive abnormalities. The final diagnosis was determined during clinical follow-up of 10.1 months ± 10.8. A final diagnosis was established in 113 patients, 52 of whom had AD. The probability of AD was 0.19 for normal perfusion 0.82 for bilateral posterotemporal and/or parietal defects, 0.77 for bilateral posterotemporal and/or parietal defects with additional defects, 0.57 for unilateral posterotemporal and/or parietal defects with or without additional defects, 0.25 for defects not involving the posterotemporal and/or parietal cortex, and 0.0 for small cortical defects. Of nine patients with bilateral posterotemporal and/or parietal defects with AD, six had Parkinson disease dementia

  13. Scintigraphic evaluation of gastrointestinal bleeding

    International Nuclear Information System (INIS)

    Park, Yong Tai; Lee, Choon Keun; Lee, Sun Wha; Choi, Woo Suk; Yoon, Yup; Lim, Jae Hoon

    1988-01-01

    Gastrointestinal bleeding remains a major diagnostic problem. Although advances have been made in the medical and surgical methods of managing gastrointestinal bleeding, the commonly employed techniques of barium radiography, endoscopy, and angiography may not successfully localize the site and define the cause of gastrointestinal bleeding. Two widely available technetium-99m-labeled radiopharmaceuticals, sulfur colloid and red blood cells are currently used in the evaluation of patients who are bleeding from the gastrointestinal tract. Surgically confirmed 19 patients with use of 99m Tc-sulfur colloid (7 cases) and 99m Tc-RBC (12 cases) were retrospectively evaluated. The overall sensitivity of scintigraphy in detection of bleeding and localization of bleeding site was 68% and 84%, respectively. The authors conclude that bleeding scintigraphy is a safe, sensitive, and non-invasive method as an effective screening test before performing angiography or surgery.

  14. Scintigraphic assessment of gastrointestinal motility

    DEFF Research Database (Denmark)

    Madsen, Jan Lysgård

    2014-01-01

    intestinal and colonic transit. This article reviews current imaging techniques, methods for data processing and principles for evaluating results when scintigraphy is used to assess gastrointestinal motility. Furthermore, clinical indications for performing scintigraphy are reviewed.......Gastrointestinal transit reflects overall gastrointestinal motor activity and is regulated by a complex interplay between neural and hormonal stimuli. Thus, transit measurements provide a measure of the combined effects of gastrointestinal muscular activity and feedback from the gut and brain....... Dysmotility in the different major segments of the gastrointestinal tract may give rise to similar symptoms; hence, localizing transit abnormalities to a specific segment is a valuable element of diagnostic evaluation. Scintigraphy is an effective noninvasive tool to assess gastric emptying as well as small...

  15. Scintigraphic detection of osteoid osteoma

    International Nuclear Information System (INIS)

    Winter, P.F.; Johnson, P.M.; Hilal, S.K.; Feldman, F.

    1977-01-01

    Bone scanning with /sup 99m/Tc-diphosphonate disclosed a solitary focus of intense activity in a cervical vertebra of a 17-year-old youth with persistent unexplained neck pain. Surgery subsequently demonstrated a well-circumscribed osteoid osteoma. This experience is further evidence of the efficacy of radionuclide skeletal scintigraphy in the evaluation of benign bone disease

  16. Scintigraphic detection of osteoid osteoma

    Energy Technology Data Exchange (ETDEWEB)

    Winter, P.F.; Johnson, P.M.; Hilal, S.K.; Feldman, F.

    1977-01-01

    Bone scanning with /sup 99m/Tc-diphosphonate disclosed a solitary focus of intense activity in a cervical vertebra of a 17-year-old youth with persistent unexplained neck pain. Surgery subsequently demonstrated a well-circumscribed osteoid osteoma. This experience is further evidence of the efficacy of radionuclide skeletal scintigraphy in the evaluation of benign bone disease.

  17. Scintigraphic assessment of Barrett's esophagus

    International Nuclear Information System (INIS)

    Kotler, J.A.; Sampliner, R.E.; Kogan, F.J.; Henry, R.E.; Mason, B.F.

    1984-01-01

    Barrett's (B) esophagus is defined by the presence of columnar epithelium above the gastroesophageal junction. Patients with 5cm histologically proven B were evaluated for mucosal labeling (ML), esophageal motility (EM), gastroesophageal reflux (GER), and gastric emptying (GE) of solids and liquids with and without iv metaclopramide (MCP). ML, after premedication with cimetidine, was evaluated 20 and 40 min after injection of Tc-99m04 with ANT and RAO views. Eight of 11 B and 0 of 2 controls (C) labeled esophageal mucosa. EM was assessed in the supine position over one min after a 15 ml swallow Tc-99mSc-H2O. The normal pattern shows sequential, aboral, discreet peaks with no retrograde movement over one min in three computer derived regions over the esophagus. Five of 16 B and 1 of 6 C demonstrated abnormal pattern. GER was assessed in the supine position by serially increasing extrinsic binder pressures from 0 to 100 Torr after ingestion of 300 ml of Tc-99mSc-orange juice (OJ). GER was present in 13 of 15 B and 0 of 11 C. Reflux ranged from 5.1% to 30% at 100 Torr. Hiatal hernia (HH) was identified in 14 of 16 B by endoscopy and in 10 of 16 by scintigraphy. GE was evaluated after a liquid meal of 300 ml Tc-99mSc-OJ and a solid meal of Tc-99mSc-egg salad sandwich. The supine subject was imaged anteriorly for 30 min (liquid) or 60 min (solid). GE was assessed an additional 10 min after MCP. Clearance time (50%) for solid Ge was calculated from extrapolated linear fits of decay corrected data. There was no significant difference in liquid or solid GE between B and C. The authors conclude the following: 1) ML detects B with lower sensitivity than previously reported; 2) EM disorders are frequently found in B; 3) GER is frequently identified in B; 4) HH can be identified by nuclear technique; and 5) B shows normal GE and responds to MCP

  18. Scintigraphic examinations concerning back pain

    International Nuclear Information System (INIS)

    Mueller-Brand, J.

    1983-01-01

    Radinuclide skeletal scintigraphy is recognized as a screening method for patients with back pain. The analog scintigram is a functional image with high sensitivity and low specificity. The improvement in specificity can be achieved using computer procedures as digital imaging, smoothing, contrast enhancement and profile selection to quantitate certain properties of the scan. Three-phase-skeletal scintigraphy, 67-Ga-citrate or 111-In labeled leucocytes augement the specificity, too. (orig.)

  19. The Stockouts Study: an Examination of the Extent and the Causes in the São Paulo Supermarket Sector

    Directory of Open Access Journals (Sweden)

    Luis Henrique Rigato Vasconcellos

    2009-07-01

    Full Text Available Stockouts remain a significant retail problem. Progress has been limited, as estimates of stockout rates in the past forty years have consistently averaged above 8 percent. The purpose of this study is to investigate the importance and extent of the stockout problem in the supermarket sector in the state of São Paulo, Brazil, from the perspective of the supermarket managers themselves. Results suggest that the level of stockouts is high. Generally, the suppliers are mentioned as being the ones mainly responsible for stockouts. These results suggest that managers have significant opportunities to reduce retail stockouts by taking preventative actions.

  20. The extent of community and public support available to families caring for orphans in Malawi.

    Science.gov (United States)

    Kidman, Rachel; Heymann, S Jody

    2009-04-01

    There are an estimated 15 million AIDS orphans worldwide. Families play an important role in safeguarding orphans, but they may be increasingly compromised by the HIV/AIDS epidemic. The international aid community has recognized the need to help families continue caring for orphaned children by strengthening their safety nets. Before we build new structures, however, we need to know the extent to which community and public safety nets already provide support to families with orphans. To address this gap, we analyzed nationally representative data from 27,495 children in the 2004-2005 Malawi Integrated Household Survey. We found that communities commonly assisted orphan households through private transfers; organized responses to the orphan crisis were far less frequent. Friends and relatives provided assistance to over 75% of orphan households through private gifts, but the value of such support was relatively low. Over 40% of orphans lived in a community with support groups for the chronically ill and approximately a third of these communities provided services specifically for orphans and other vulnerable children. Public programs, which form a final safety net for vulnerable households, were more widespread. Free/subsidized agricultural inputs and food were the most commonly used public safety nets by children's households in the past year (44 and 13%, respectively), and households with orphans were more likely to be beneficiaries. Malawi is poised to drastically expand safety nets to orphans and their families, and these findings provide an important foundation for this process.

  1. Revisiting Gill's Circulation. Dynamic Response to Diabatic Heating of Different Horizontal Extents

    Science.gov (United States)

    Reboredo, B.; Bellon, G.

    2017-12-01

    The horizontal extent of diabatic heating associated with the MJO is thought to be crucial to its development, and the inability of GCMs to simulate the spatial, horizontal organization of clouds is considered a leading hypothesis to explain their limited capacity to simulate MJO events. This prevents the MJO large-circulation response from developing and feeding back on the development of clouds. We apply mid-tropospheric heating of different size in simple linear and non-linear models of the tropical atmosphere following Gill's seminal work on heat-induced tropical circulations. Results show that there is a scale for which the characteristic circulation {Γ c} for the vertical advection of moisture to produce the latent heat mean {Q} gives a rough estimate of the real world MJO scale. Overturning circulation flow rates above {Γ c} account for a circulation that transports more moisture than necessary to be maintained, and below {Γ c}, circulation would not transport enough moisture to maintain circulation. This dynamic scale might constrain the size of the spatially-organised convection necessary to the development of an MJO event. However, other effects are expected to modulate this scale, such as vertical advection of moisture anomalies, horizontal advection, evaporation, radiative heating, and sensible heat fluxes.

  2. Demand for cooking fuels in a developing country: To what extent do taste and preferences matter?

    International Nuclear Information System (INIS)

    Akpalu, Wisdom; Dasmani, Isaac; Aglobitse, Peter B.

    2011-01-01

    Overreliance on biomass energy, such as firewood and charcoal, for cooking in developing countries has contributed to high rates of deforestation and resulted in substantial indoor pollution, which has negatively impacted the health of many individuals. However, the effectiveness of public policies aimed at encouraging households to switch to cleaner fuels, such as liquefied petroleum gas (LPG) and kerosene, hinges on the extent to which they are mentally committed to specific fuels. Using data on four cooking fuels (charcoal, firewood, LPG, and kerosene) from the Ghana living standards survey, we found strong evidence that the most preferred fuel is LPG, followed by charcoal, with kerosene the least preferred. In addition, with the exception of kerosene that has price-elastic demand, the price elasticities of demand for the fuel types examined are inelastic. This finding suggests the so-called fuel-ladder is not robust. - Highlights: → Overreliance on biomass energy for cooking has contributed to deforestation and indoor pollution. → We estimate demand for four cooking fuels (charcoal, firewood, LPG, and kerosene) in Ghana. → We found that the most preferred fuel is LPG, followed by charcoal, with kerosene the least preferred. → This finding suggests the so-called fuel-ladder is not robust.

  3. Identifying tropical dry forests extent and succession via the use of machine learning techniques

    Science.gov (United States)

    Li, Wei; Cao, Sen; Campos-Vargas, Carlos; Sanchez-Azofeifa, Arturo

    2017-12-01

    Information on ecosystem services as a function of the successional stage for secondary tropical dry forests (TDFs) is scarce and limited. Secondary TDFs succession is defined as regrowth following a complete forest clearance for cattle growth or agriculture activities. In the context of large conservation initiatives, the identification of the extent, structure and composition of secondary TDFs can serve as key elements to estimate the effectiveness of such activities. As such, in this study we evaluate the use of a Hyperspectral MAPper (HyMap) dataset and a waveform LIDAR dataset for characterization of different levels of intra-secondary forests stages at the Santa Rosa National Park (SRNP) Environmental Monitoring Super Site located in Costa Rica. Specifically, a multi-task learning based machine learning classifier (MLC-MTL) is employed on the first shortwave infrared (SWIR1) of HyMap in order to identify the variability of aboveground biomass of secondary TDFs along a successional gradient. Our paper recognizes that the process of ecological succession is not deterministic but a combination of transitional forests types along a stochastic path that depends on ecological, edaphic, land use, and micro-meteorological conditions, and our results provide a new way to obtain the spatial distribution of three main types of TDFs successional stages.

  4. Demand for cooking fuels in a developing country: To what extent do taste and preferences matter?

    Energy Technology Data Exchange (ETDEWEB)

    Akpalu, Wisdom, E-mail: wakpalu@yahoo.com [Department of History, Economics and Politics, Farmingdale State College, State University of New York, Farmingdale, 2350 Broadhollow Road, NY 11735 (United States); Dasmani, Isaac; Aglobitse, Peter B. [Department of Economics, University of Cape Coast, Cape Coast (Ghana)

    2011-10-15

    Overreliance on biomass energy, such as firewood and charcoal, for cooking in developing countries has contributed to high rates of deforestation and resulted in substantial indoor pollution, which has negatively impacted the health of many individuals. However, the effectiveness of public policies aimed at encouraging households to switch to cleaner fuels, such as liquefied petroleum gas (LPG) and kerosene, hinges on the extent to which they are mentally committed to specific fuels. Using data on four cooking fuels (charcoal, firewood, LPG, and kerosene) from the Ghana living standards survey, we found strong evidence that the most preferred fuel is LPG, followed by charcoal, with kerosene the least preferred. In addition, with the exception of kerosene that has price-elastic demand, the price elasticities of demand for the fuel types examined are inelastic. This finding suggests the so-called fuel-ladder is not robust. - Highlights: > Overreliance on biomass energy for cooking has contributed to deforestation and indoor pollution. > We estimate demand for four cooking fuels (charcoal, firewood, LPG, and kerosene) in Ghana. > We found that the most preferred fuel is LPG, followed by charcoal, with kerosene the least preferred. > This finding suggests the so-called fuel-ladder is not robust.

  5. Regional decline of coral cover in the Indo-Pacific: timing, extent, and subregional comparisons.

    Directory of Open Access Journals (Sweden)

    John F Bruno

    2007-08-01

    Full Text Available A number of factors have recently caused mass coral mortality events in all of the world's tropical oceans. However, little is known about the timing, rate or spatial variability of the loss of reef-building corals, especially in the Indo-Pacific, which contains 75% of the world's coral reefs.We compiled and analyzed a coral cover database of 6001 quantitative surveys of 2667 Indo-Pacific coral reefs performed between 1968 and 2004. Surveys conducted during 2003 indicated that coral cover averaged only 22.1% (95% CI: 20.7, 23.4 and just 7 of 390 reefs surveyed that year had coral cover >60%. Estimated yearly coral cover loss based on annually pooled survey data was approximately 1% over the last twenty years and 2% between 1997 and 2003 (or 3,168 km(2 per year. The annual loss based on repeated measures regression analysis of a subset of reefs that were monitored for multiple years from 1997 to 2004 was 0.72 % (n = 476 reefs, 95% CI: 0.36, 1.08.The rate and extent of coral loss in the Indo-Pacific are greater than expected. Coral cover was also surprisingly uniform among subregions and declined decades earlier than previously assumed, even on some of the Pacific's most intensely managed reefs. These results have significant implications for policy makers and resource managers as they search for successful models to reverse coral loss.

  6. NEPHRUS: model of intelligent multilayers expert system for evaluation of the renal system based on scintigraphic images analysis; NEPRUS: modelo de sistema especialista em multicamadas inteligentes para avaliacao do sistema urinario baseado na analise de imagens cintilograficas

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Jose W.E. da; Schirru, Roberto [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia; Boasquevisque, Edson M. [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Servico de Medicina Nuclear

    1997-10-01

    This work develops a prototype for the system model based on Artificial Intelligence devices able to perform functions related to scintigraphic image analysis of the urinary system. Criteria used by medical experts for analysis images obtained with {sup 99m} Tc+DTPA and/or {sup 99m} Tc+DMSA were modeled and a multi resolution diagnosis technique was implemented. Special attention was given to the programs user interface design. Human Factor Engineering techniques were considered so as to ally friendliness and robustness. Results obtained using Artificial Neural Networks for the qualitative image analysis and the knowledge model constructed shows the feasibility of Artificial Intelligence implementation that use `inherent` abilities of each technique in the resolution of diagnosis image analysis problems. (author). 12 refs., 2 figs., 2 tabs.

  7. Evaluation of the use of technetium Tc 99m diethylenetriamine pentaacetic acid and technetium Tc 99m dimercaptosuccinic acid for scintigraphic imaging of the kidneys in green iguanas (Iguana iguana).

    Science.gov (United States)

    Greer, Leah L; Daniel, Gregory B; Shearn-Bochsler, Valerie I; Ramsay, Edward C

    2005-01-01

    To evaluate the use of scintigraphy involving technetium Tc 99m diethylenetriamine pentaacetic acid ((99m)Tc-DTPA) or technetium Tc 99m dimercaptosuccinic acid ((99m)Tc-DMSA) for the determination of kidney morphology and function in green iguanas (Iguana iguana). 10 healthy iguanas weighing >1.6 kg. Renal scintigraphy was performed by use of (99m)Tc-DTPA in 6 of the iguanas and by use of (99m)Tc-DMSA in all 10 iguanas. After the injection of (99m)Tc-DMSA, scans were performed for each iguana at intervals during a 20-hour period. Renal biopsies were performed in all 10 iguanas after the final scintigraphic evaluation. In iguanas, the use of (99m)Tc-DTPA for renal scintigraphy was nondiagnostic because of serum protein binding and poor renal uptake of the isotope; mean +/- SD (99m)Tc-DTPA bound to serum proteins was 48.9 +/- 9.9%. Renal uptake of (99m)Tc-DMSA produced distinct visualization of both kidneys. Renal uptake and soft tissue clearance of (99m)Tc-DMSA increased over the 20-hour imaging period; mean +/- SD renal uptake of (99m)Tc-DMSA was 11.31 +/- 3.06% at 20 hours. In each of the 10 iguanas, ultrasonographic and histologic examinations of biopsy specimens from both kidneys revealed no abnormalities. Results indicate that the kidneys of iguanas can be evaluated scintigraphically by use of (99m)Tc-DMSA; this technique may be potentially useful for the diagnosis of renal failure in iguanas.

  8. Normative values of 99mTc-MIBI distribution in myocardium in males and females, as a basis for quantitative planar scintigraphic method for detection of coronary artery disease in patients of both sexes

    International Nuclear Information System (INIS)

    Kusmierek, J.; Plachcinska, A.

    2001-01-01

    Radionuclide perfusion studies of myocardium are being performed using planar and tomographic (SPECT) procedures. The latter method enables better detection as well as assessment of localisation and severity of scintigraphically visualised perfusion defects. On the other hand, lower cost of planar procedures using 99m Tc-MIBI as the tracer and their much wider availability in countries of Central and Eastern Europe could significantly increase the diagnostic potential of nuclear cardiology in this region.The aim of the study was an assessment of normal distribution of 99m Tc-MIBI in the myocardium and generation of normative basis for quantitative planar scintigraphic procedure, aiming at detection of CAD in patients of both sexes.The study was based on 250 patients. The reference (control) group consisted of 53 individuals (29 men, 24 women) with the low ( 0 and LAO 70 0 ). These mean curves differed significantly between both sexes. In LAO 45 0 projection the differences affected mostly the region of the septum and postero-lateral wall of the left ventricle (LV). In LAO 70 0 projection differences were most pronounced in the antero-septal wall of the LV. Sensitivity, specificity and accuracy of CAD detection using the elaborated method, taking into account inter-sex differences, amounted to 86, 87 and 86% respectively in males, and correspondingly 81, 84 and 83% in females. The differences between corresponding indices for two sexes were statistically insignificant. For the whole group of patients the sensitivity, specificity and accuracy was 85, 86 and 85%, respectively. (author)

  9. The extent of cigarette brand and company switching: results from the Adult Use-of-Tobacco Survey.

    Science.gov (United States)

    Siegel, M; Nelson, D E; Peddicord, J P; Merritt, R K; Giovino, G A; Eriksen, M P

    1996-01-01

    To evaluate the effects of cigarette advertising on brand switching, an accurate estimate of the extent of cigarette brand and company switching among current smokers is needed. Data from the 1986 Adult Use-of-Tobacco Survey were analyzed to estimate the percentage of adult smokers who switched cigarette brands and companies in the previous year. Approximately 9.2% of adult smokers (4.2 million) switched cigarette brands in 1986, and 6.7% (3.1 million) switched cigarette companies. The aggregate profitability of brand switching in 1986 was approximately $362 million. Based on this analysis, brand switching alone justifies only a small percentage of a cigarette company's advertising and promotion expenditures, suggesting that future research should address other potential effects of advertising, including maintenance of brand loyalty and expanding the cigarette market. Medical Subject Headings (MeSH): addictive behavior, advertising, smoking, tobacco.

  10. Map of the approximate inland extent of saltwater at the base of the Biscayne aquifer in the Model Land Area of Miami-Dade County, Florida, 2016

    Science.gov (United States)

    Prinos, Scott T.

    2017-07-11

    The inland extent of saltwater at the base of the Biscayne aquifer in the Model Land Area of Miami-Dade County, Florida, was mapped in 2011. Since that time, the saltwater interface has continued to move inland. The interface is near several active well fields; therefore, an updated approximation of the inland extent of saltwater and an improved understanding of the rate of movement of the saltwater interface are necessary. A geographic information system was used to create a map using the data collected by the organizations that monitor water salinity in this area. An average rate of saltwater interface movement of 140 meters per year was estimated by dividing the distance between two monitoring wells (TPGW-7L and Sec34-MW-02-FS) by the travel time. The travel time was determined by estimating the dates of arrival of the saltwater interface at the wells and computing the difference. This estimate assumes that the interface is traveling east to west between the two monitoring wells. Although monitoring is spatially limited in this area and some of the wells are not ideally designed for salinity monitoring, the monitoring network in this area is improving in spatial distribution and most of the new wells are well designed for salinity monitoring. The approximation of the inland extent of the saltwater interface and the estimated rate of movement of the interface are dependent on existing data. Improved estimates could be obtained by installing uniformly designed monitoring wells in systematic transects extending landward of the advancing saltwater interface.

  11. Mixture model to assess the extent of cross-transmission of multidrug-resistant pathogens in hospitals.

    Science.gov (United States)

    Mikolajczyk, Rafael T; Kauermann, Göran; Sagel, Ulrich; Kretzschmar, Mirjam

    2009-08-01

    Creation of a mixture model based on Poisson processes for assessment of the extent of cross-transmission of multidrug-resistant pathogens in the hospital. We propose a 2-component mixture of Poisson processes to describe the time series of detected cases of colonization. The first component describes the admission process of patients with colonization, and the second describes the cross-transmission. The data set used to illustrate the method consists of the routinely collected records for methicillin-resistant Staphylococcus aureus (MRSA), imipenem-resistant Pseudomonas aeruginosa, and multidrug-resistant Acinetobacter baumannii over a period of 3 years in a German tertiary care hospital. For MRSA and multidrug-resistant A. baumannii, cross-transmission was estimated to be responsible for more than 80% of cases; for imipenem-resistant P. aeruginosa, cross-transmission was estimated to be responsible for 59% of cases. For new cases observed within a window of less than 28 days for MRSA and multidrug-resistant A. baumannii or 40 days for imipenem-resistant P. aeruginosa, there was a 50% or greater probability that the cause was cross-transmission. The proposed method offers a solution to assessing of the extent of cross-transmission, which can be of clinical use. The method can be applied using freely available software (the package FlexMix in R) and it requires relatively little data.

  12. Bayesian estimates of linkage disequilibrium

    Directory of Open Access Journals (Sweden)

    Abad-Grau María M

    2007-06-01

    Full Text Available Abstract Background The maximum likelihood estimator of D' – a standard measure of linkage disequilibrium – is biased toward disequilibrium, and the bias is particularly evident in small samples and rare haplotypes. Results This paper proposes a Bayesian estimation of D' to address this problem. The reduction of the bias is achieved by using a prior distribution on the pair-wise associations between single nucleotide polymorphisms (SNPs that increases the likelihood of equilibrium with increasing physical distances between pairs of SNPs. We show how to compute the Bayesian estimate using a stochastic estimation based on MCMC methods, and also propose a numerical approximation to the Bayesian estimates that can be used to estimate patterns of LD in large datasets of SNPs. Conclusion Our Bayesian estimator of D' corrects the bias toward disequilibrium that affects the maximum likelihood estimator. A consequence of this feature is a more objective view about the extent of linkage disequilibrium in the human genome, and a more realistic number of tagging SNPs to fully exploit the power of genome wide association studies.

  13. Failing to Estimate the Costs of Offshoring

    DEFF Research Database (Denmark)

    Møller Larsen, Marcus

    2016-01-01

    This article investigates cost estimation errors in the context of offshoring. It is argued that an imprecise estimation of the costs related to implementing a firm activity in a foreign location has a negative impact on the process performance of that activity. Performance is deterred...... as operations are likely to be disrupted by managerial distraction and resource misallocation. It is also argued that this relationship is mitigated by the extent to which firms use modularity to coordinate the activity but worsened by the extent to which ongoing communication is used. The results, based...

  14. 34 CFR 600.10 - Date, extent, duration, and consequence of eligibility.

    Science.gov (United States)

    2010-07-01

    ... 34 Education 3 2010-07-01 2010-07-01 false Date, extent, duration, and consequence of eligibility... EDUCATION ACT OF 1965, AS AMENDED General § 600.10 Date, extent, duration, and consequence of eligibility... statutory and regulatory requirements governing its eligibility. (e) Consequence of eligibility. (1) If, as...

  15. Prevalence, Vascular Distribution, and Multiterritorial Extent of Subclinical Atherosclerosis in a Middle-Aged Cohort

    DEFF Research Database (Denmark)

    Fernández-Friera, Leticia; Peñalvo, José L; Fernández-Ortiz, Antonio

    2015-01-01

    age, 45.8 years; 63% male) to evaluate the systemic extent of atherosclerosis in the carotid, abdominal aortic, and iliofemoral territories by 2-/3-dimensional ultrasound and coronary artery calcification by computed tomography. The extent of subclinical atherosclerosis, defined as presence of plaque...

  16. Extent of resection and timing of surgery in adult low grade glioma.

    Science.gov (United States)

    A Mirza, Farhan; Shamim, Muhammad Shahzad

    2017-06-01

    Low grade glioma is a group of WHO grade II tumours including diffuse astrocytoma, oligodendroglioma, and oligoastrocytoma. Strong evidence exists in literature now to support early surgery and higher extent of safe resection in improving outcomes. In this review, we are highlighting some of the important studies done in the last few years specifically addressing timing of surgery and extent of resection.

  17. Effects of geographical extent on the determinants of woody plant diversity

    DEFF Research Database (Denmark)

    Wang, Zhiheng; Rahbek, Carsten; Fang, Jingyun

    2012-01-01

    the quantitative effects of geographical extent are rarely tested. Here, using distribution maps of 11,405 woody species found in China and associated environmental data to the domain, we investigated the influence of geographical extent on the determinants of species richness patterns. Our results revealed...

  18. Extent and status of mires, peatlands, and organic soils in Europe

    Science.gov (United States)

    Tanneberger, Franziska; Barthelmes, Alexandra; Tegetmeyer, Cosima; Busse, Stephan; Joosten, Hans

    2016-04-01

    Key words: peatland distribution, peatland drainage, GIS, Global Peatland Database, European Mires Book The relevance of drained peatlands to climate change due to emission of huge amounts of greenhouse gases has recently been recognised e.g. by IPCC, FAO, and the European Union. Oppositely, natural and restored peatlands provide ecosystem services like enhancing biodiversity, nutrient retention, groundwater storage, flood mitigation, and cooling. To evaluate the drainage status of peatlands and organic soils and to develop specific restoration strategies comprehensive and exact geospatial data are needed. The Global Peatland Database (GPD) is hosted at Greifswald Mire Centre (http://tiny.cc/globalpeat). Currently, it provides estimates on location, extent, and drainage status of peatlands and organic soils for 268 countries and regions of the world. Due to the large diversity of definitions and terms for peatlands and organic soils, this mapping follows the broad definition of organic soils from IPCC that gives a minimum soil organic carbon threshold of 12% and considers any depth of the organic layer larger than 10 cm. GIS datasets are continuously collected, specific terms and definitions analysed and the completeness and accuracy of the datasets evaluated. Currently, the GPD contains geospatial data on peatlands and organic soils for all European countries (except Moldova). Recent information on status, distribution, and conservation of mires and peatlands in Europe is summarised in the European Mires Book. It includes descriptions from 49 countries and other geographic entities in Europe. All country chapters follow a generic structure and include also extensive descriptions of national terminology (also in national languages and script) and typologies as well as up to date area statistics and maps. They are complemented by integrative chapters presenting mire classification, mire regionality, peatland use, and mire conservation in Europe. The European Mires

  19. Quantifying the extent of North American mammal extinction relative to the pre-anthropogenic baseline.

    Science.gov (United States)

    Carrasco, Marc A; Barnosky, Anthony D; Graham, Russell W

    2009-12-16

    Earth has experienced five major extinction events in the past 450 million years. Many scientists suggest we are now witnessing a sixth, driven by human impacts. However, it has been difficult to quantify the real extent of the current extinction episode, either for a given taxonomic group at the continental scale or for the worldwide biota, largely because comparisons of pre-anthropogenic and anthropogenic biodiversity baselines have been unavailable. Here, we compute those baselines for mammals of temperate North America, using a sampling-standardized rich fossil record to reconstruct species-area relationships for a series of time slices ranging from 30 million to 500 years ago. We show that shortly after humans first arrived in North America, mammalian diversity dropped to become at least 15%-42% too low compared to the "normal" diversity baseline that had existed for millions of years. While the Holocene reduction in North American mammal diversity has long been recognized qualitatively, our results provide a quantitative measure that clarifies how significant the diversity reduction actually was. If mass extinctions are defined as loss of at least 75% of species on a global scale, our data suggest that North American mammals had already progressed one-fifth to more than halfway (depending on biogeographic province) towards that benchmark, even before industrialized society began to affect them. Data currently are not available to make similar quantitative estimates for other continents, but qualitative declines in Holocene mammal diversity are also widely recognized in South America, Eurasia, and Australia. Extending our methodology to mammals in these areas, as well as to other taxa where possible, would provide a reasonable way to assess the magnitude of global extinction, the biodiversity impact of extinctions of currently threatened species, and the efficacy of conservation efforts into the future.

  20. Acid mine drainage in Australia: its extent and potential future liability. Supervising Scientist Report 125

    International Nuclear Information System (INIS)

    Harries, J.

    1997-01-01

    In order to better understand the impact of acid drainage in Australia and to provide a basis for assessing long-term management options, the Office of the Supervising Scientist (OSS) and the Australian Centre for Minesite Rehabilitation Research (ACMRR) initiated this study to prepare a status report on acid mine drainage in Australia. The study is supported by the Minerals Council of Australia. The coverage of this study includes all mine sites where sulphidic oxidation in mine wastes or mine workings leads to the release of contaminated drainage with off-site impacts. The objectives of the study were: 1. to quantify and characterise the generation of contaminated drainage by sulphidic oxidation from historic and current mining activities in Australia; 2. to develop a classification scheme to characterise the potential for off-site impacts from sulphidic oxidation in mine wastes; 3. to compare the cost at the national level of managing sulphidic oxidation in mine wastes and any resulting contaminated drainage with other mining and environmental costs; 4. to make recommendations based on the information received to improve the understanding and management of acid mine drainage in Australia. Information was collected on the extent and management of sulphidic oxidation and acid drainage at operating, historic and derelict mines in Australia. Mining operators, environmental officers, industry representatives, state government departments and others were asked about their experience with acid mine drainage and how it is currently managed at operating and historic mine sites. Based on the information collected, the additional cost of managing potentially acid generating wastes at operating mine sites is estimated to be about AUD 60 million per year. Potentially, the financial risk could be much greater if sulphide oxidation and release of pollutants is discovered after mine closure, as was the case for historic sites like Mt Lyell, Rum Jungle or Mt Morgan. The