The Experts below are selected from a list of 285 Experts worldwide ranked by ideXlab platform
Dragana Radovanovic - One of the best experts on this subject based on the ideXlab platform.
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blue dye versus combined blue dye Radioactive Tracer technique in detection of sentinel lymph node in breast cancer
Ejso, 2004Co-Authors: Zoran Radovanovic, Andrija Golubovic, A Plzak, B Stojiljkovic, Dragana RadovanovicAbstract:Background. Sentinel lymph node biopsy in breast cancer can be used to select patients in which axillary lymph node dissection could be avoided. In this study we compared the value of two methods for identification of sentinel node (SN) using either only blue dye or combination of blue dye and Radioactive Tracer.
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blue dye versus combined blue dye Radioactive Tracer technique in detection of sentinel lymph node in breast cancer
Ejso, 2004Co-Authors: Zora Radovanovic, Andrija Golubovic, A Plzak, Dragana RadovanovicAbstract:BACKGROUND: Sentinel lymph node biopsy in breast cancer can be used to select patients in which axillary lymph node dissection could be avoided. In this study we compared the value of two methods for identification of sentinel node (SN) using either only blue dye or combination of blue dye and Radioactive Tracer. MATERIAL AND METHODS: All patients were women with clinically T(1-2)N(0)M(0) breast cancer. They were randomized into two groups. In Group A (50 patients) SN marking was performed only with blue dye and in Group B (100 patients) combined SN marking with blue dye and radioTracer was done. We used 2 ml of blue dye Patentblau V (Byk Gulden). RadioTracer was Antimony sulfide marked with Tc 99m and of 0.3 mCy (11.1 MBq) activity. Application method of both contrasts was peritumoral. After SN biopsy all patients underwent mastectomy or conservative surgery with axillary lymph node dissection of levels I and II. RESULTS: In Group A mean of 1.7 SNs were identified (median 1, range 1-4). False-negative rate in this group was 3/17 (17.6%) with negative-predictive value 20/23 (86.9%), sensitivity 14/17 (82%), specificity 20/33 (60%) and accuracy 34/50 (68%). In Group B mean number of SNs excised per case was 1.6 (median 1, range 1-5). False-negative rate was 2/44 (4.5%), negative-predictive value 41/43 (95.3%), sensitivity 42/44 (95%), specificity 41/56 (73%) and accuracy 83/100 (83%). The combination technique was significantly superior to blue-dye alone technique for negative-predictive value (p=0.033) and overall accuracy (p=0.048). CONCLUSIONS: The prediction of axillary lymph node status in breast cancer patients using combined technique has significantly higher accuracy than marking of SN with blue dye alone and therefore should be preferred.
Bernard Allen Toseland - One of the best experts on this subject based on the ideXlab platform.
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hydrodynamics of slurry bubble column during dimethyl ether dme synthesis gas liquid recirculation model and Radioactive Tracer studies
Chemical Engineering Science, 2006Co-Authors: P Chen, P Gupta, M P Dudukovic, Bernard Allen ToselandAbstract:Radioactive Tracer measurements, using impulse injections of Ar41, powdered oxide of Mn56 and real catalyst particles doped with an oxide of Mn56, conducted at the Advance Fuels Development Unit (AFDU) slurry bubble column (BC) reactor during dimethyl ether (DME) synthesis (reactor pressure of 5.27 MPa, reactor temperature of T=250∘C, inlet superficial gas velocity of 17.1 cm/s, and a catalyst loading of 36 wt%) at LaPorte, Texas, are interpreted. The differences in the responses obtained by the catalyst and fine powdered Mn2O3 Tracer injections are minimal indicating the validity of the pseudo-homogeneous assumption for the liquid plus solid (catalyst) phase mixtures. The gas–liquid recirculation model [Gupta et al., 2001a. Comparison of single- and two-bubble class gas–liquid recirculation models—application to pilot-plant Radioactive Tracer studies during methanol synthesis. Chemical Engineering Science 56(3), 1117–1125. 2001b. Hydrodynamics of churn turbulent bubble columns: gas–liquid recirculation and mechanistic modeling. Catalysis Today 64(3–4), 253–269], based on a constant bubble size, describing gas–liquid mass transfer superimposed on turbulent mixing of the gas and liquid phases, is used to simulate the gas, liquid and catalyst Tracer responses acquired at the AFDU. The model is able to predict the characteristic features of the experimental responses observed for gas, slurry powder and catalyst Tracers at different reactor elevations. The fact, that the same model was previously shown capable of predicting both gas and liquid Radioactive Tracer responses during methanol and Fischer–Tropsch (FT) synthesis, indicates that this model offers a relatively simple tool for assessing mixing and transport in bubble (BCs) for a variety of gas conversion processes and provides a phenomenologically based framework for BC reactor modeling.
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flow patterns in a slurry bubble column reactor under reaction conditions
Chemical Engineering Research & Design, 1995Co-Authors: Bernard Allen Toseland, D M Brown, M P DudukovicAbstract:The gas and liquid Radioactive Tracer response curves obtained in an industrial bubble column reactor of height to diameter ratio of 10 are analysed and the suitability of the axial dispersion model for interpretation of the results is discussed. The relationship between the Tracer concentration distribution and measured detector response is calculated. It is found that the liquid can be considered well mixed and that the response of the soluble gas Tracer (Ar-41) is possibly dominated by the dissolved gas. The one dimensional axial dispersion model cannot match all the experimental observations well and the flow pattern of the undissolved gas cannot be determined with certainty
Jane K Willenbring - One of the best experts on this subject based on the ideXlab platform.
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steady state reach scale theory for Radioactive Tracer concentration in a simple channel floodplain system
Journal of Geophysical Research, 2010Co-Authors: Wesley J Lauer, Jane K WillenbringAbstract:[1] A steady state analytical model is presented for reach-scale variation in the concentration of a decaying Radioactive Tracer associated with sediment particles that regularly pass through an off-channel floodplain. The floodplain is represented as a series of well-mixed sediment reservoirs that continually exchange sediment with the channel. The model allows for tributary input and valley-wide aggradation or degradation. Tracer concentration depends on the upstream boundary concentration, the Tracer and sediment load, floodplain geometry, and the rates of in-floodplain Tracer production and/or decay. The theory predicts relatively modest down-channel change in the concentration of long-lived isotopes but implies that significant change may occur for (1) Tracers with a short-enough half-life (such as 14C) or (2) floodplains with sediment residence times that are large enough for cosmogenic production or meteoric fallout to increase Tracer concentration in the down-valley direction. The profiles are shown to be strongly dependent on the grain size distributions of both the sediment load and the floodplain. The results imply that down-channel 14C profiles have the potential to constrain Holocene bed material loads in systems with sufficient storage. The theory concisely describes the general importance of a floodplain for modifying in situ produced cosmogenic Tracer concentration and can also characterize floodplain importance for fallout radioisotopes (i.e., 10Be, 210Pb, or 7Be) or organic 14C.
M P Dudukovic - One of the best experts on this subject based on the ideXlab platform.
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hydrodynamics of slurry bubble column during dimethyl ether dme synthesis gas liquid recirculation model and Radioactive Tracer studies
Chemical Engineering Science, 2006Co-Authors: P Chen, P Gupta, M P Dudukovic, Bernard Allen ToselandAbstract:Radioactive Tracer measurements, using impulse injections of Ar41, powdered oxide of Mn56 and real catalyst particles doped with an oxide of Mn56, conducted at the Advance Fuels Development Unit (AFDU) slurry bubble column (BC) reactor during dimethyl ether (DME) synthesis (reactor pressure of 5.27 MPa, reactor temperature of T=250∘C, inlet superficial gas velocity of 17.1 cm/s, and a catalyst loading of 36 wt%) at LaPorte, Texas, are interpreted. The differences in the responses obtained by the catalyst and fine powdered Mn2O3 Tracer injections are minimal indicating the validity of the pseudo-homogeneous assumption for the liquid plus solid (catalyst) phase mixtures. The gas–liquid recirculation model [Gupta et al., 2001a. Comparison of single- and two-bubble class gas–liquid recirculation models—application to pilot-plant Radioactive Tracer studies during methanol synthesis. Chemical Engineering Science 56(3), 1117–1125. 2001b. Hydrodynamics of churn turbulent bubble columns: gas–liquid recirculation and mechanistic modeling. Catalysis Today 64(3–4), 253–269], based on a constant bubble size, describing gas–liquid mass transfer superimposed on turbulent mixing of the gas and liquid phases, is used to simulate the gas, liquid and catalyst Tracer responses acquired at the AFDU. The model is able to predict the characteristic features of the experimental responses observed for gas, slurry powder and catalyst Tracers at different reactor elevations. The fact, that the same model was previously shown capable of predicting both gas and liquid Radioactive Tracer responses during methanol and Fischer–Tropsch (FT) synthesis, indicates that this model offers a relatively simple tool for assessing mixing and transport in bubble (BCs) for a variety of gas conversion processes and provides a phenomenologically based framework for BC reactor modeling.
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flow patterns in a slurry bubble column reactor under reaction conditions
Chemical Engineering Research & Design, 1995Co-Authors: Bernard Allen Toseland, D M Brown, M P DudukovicAbstract:The gas and liquid Radioactive Tracer response curves obtained in an industrial bubble column reactor of height to diameter ratio of 10 are analysed and the suitability of the axial dispersion model for interpretation of the results is discussed. The relationship between the Tracer concentration distribution and measured detector response is calculated. It is found that the liquid can be considered well mixed and that the response of the soluble gas Tracer (Ar-41) is possibly dominated by the dissolved gas. The one dimensional axial dispersion model cannot match all the experimental observations well and the flow pattern of the undissolved gas cannot be determined with certainty
Andrija Golubovic - One of the best experts on this subject based on the ideXlab platform.
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blue dye versus combined blue dye Radioactive Tracer technique in detection of sentinel lymph node in breast cancer
Ejso, 2004Co-Authors: Zoran Radovanovic, Andrija Golubovic, A Plzak, B Stojiljkovic, Dragana RadovanovicAbstract:Background. Sentinel lymph node biopsy in breast cancer can be used to select patients in which axillary lymph node dissection could be avoided. In this study we compared the value of two methods for identification of sentinel node (SN) using either only blue dye or combination of blue dye and Radioactive Tracer.
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blue dye versus combined blue dye Radioactive Tracer technique in detection of sentinel lymph node in breast cancer
Ejso, 2004Co-Authors: Zora Radovanovic, Andrija Golubovic, A Plzak, Dragana RadovanovicAbstract:BACKGROUND: Sentinel lymph node biopsy in breast cancer can be used to select patients in which axillary lymph node dissection could be avoided. In this study we compared the value of two methods for identification of sentinel node (SN) using either only blue dye or combination of blue dye and Radioactive Tracer. MATERIAL AND METHODS: All patients were women with clinically T(1-2)N(0)M(0) breast cancer. They were randomized into two groups. In Group A (50 patients) SN marking was performed only with blue dye and in Group B (100 patients) combined SN marking with blue dye and radioTracer was done. We used 2 ml of blue dye Patentblau V (Byk Gulden). RadioTracer was Antimony sulfide marked with Tc 99m and of 0.3 mCy (11.1 MBq) activity. Application method of both contrasts was peritumoral. After SN biopsy all patients underwent mastectomy or conservative surgery with axillary lymph node dissection of levels I and II. RESULTS: In Group A mean of 1.7 SNs were identified (median 1, range 1-4). False-negative rate in this group was 3/17 (17.6%) with negative-predictive value 20/23 (86.9%), sensitivity 14/17 (82%), specificity 20/33 (60%) and accuracy 34/50 (68%). In Group B mean number of SNs excised per case was 1.6 (median 1, range 1-5). False-negative rate was 2/44 (4.5%), negative-predictive value 41/43 (95.3%), sensitivity 42/44 (95%), specificity 41/56 (73%) and accuracy 83/100 (83%). The combination technique was significantly superior to blue-dye alone technique for negative-predictive value (p=0.033) and overall accuracy (p=0.048). CONCLUSIONS: The prediction of axillary lymph node status in breast cancer patients using combined technique has significantly higher accuracy than marking of SN with blue dye alone and therefore should be preferred.