Interpolative background subtraction Goris, M L; Daspit, S G; McLaughlin, P ...
The Journal of nuclear medicine (1978)
17, Issue:
8
Journal Article
Peer reviewed
A method for background subtraction is presented. The data are digitized scintigraphic images, stored in 64 X 64 frames. Within this array a rectangular area surrounding the target is defined. All ...data points outside of this area are set equal to zero. From each data point within the area, the computer subtracts a background value equal to the average of the two intersecting linear interpolations between the values at the edges of the rectangular area having the ordinate and abscissa values of the point of interest. The rationale for this approach is discussed and its application in myocardial perfusion studies is illustrated.
The Azua Basin sequence is a 2500 m thick Miocene Pliocene regressive interval. Limestones and marls of the Sombrerito Formation, the lowermost unit, ranges from lower Miocene to lowermost upper ...Miocene. The turbidite sequence of the Trinchera Formation spans an interval from uppermost middle Miocene to lower Pliocene. Blue-green, neritic lower Pliocene siltstones of the Quita Coraza Formation overlie the Trinchera in the seaward part of the basin. Shallow-marine strata in the lower part of the Arroyo Blanco Formation range from uppermost Miocene to middle Pliocene. Principal Components Analysis of rich benthic foraminiferal faunas aided in the recognition of species associations. Positive loadings on Factor 1 define a bathyal-neritic boundary zone assemblage: Bolivina minima (0.88), Cassidulina norcrossi var. australis (0.73), and Gyroidina regularis (0.71). Lower bathyal species Pleurostomella alternans ($-$0.64), Bolivina paula ($-$0.62), and Cibicides wuellerstorfi ($-$0.49) show strong negative loadings. Positive loadings on Factor 2 define a middle to upper bathyal assemblage: Oridorsalis umbonatus (0.68), Hoeglundina elegans (0.57), and Uvigerina peregrina (0.51). Factor 3 represents a middle to outer neritic assemblage that includes Angulogerina jamaicensis (0.83), Cassidulina carinata (0.54), and Cibicidoides pachyderma forma sublittoralis (0.51). Factor 4 has heavy loadings on inner neritic species including Haynesina depressula (0.74), and Buliminella elegantissima (0.73). Neritic species associated with Factor 5 include Cancris sagra (0.69) and Bolivina lowmani (0.59). Plots of the factor scores in the stratigraphic sections demonstrate shoaling upward from lower bathyal to inner neritic depths. Cluster analysis reveals seven major sample groupings that correspond almost directly to the faunal zones identified in the Azua Basin by Bermudez (1949). Migration of foraminiferal environments toward the Caribbean during the Miocene and Pliocene is paralleled by time-transgression of lithofacies. The southwestern Dominican Republic evolved in two stages: (1) a tectonically quite open ocean stage before the late Miocene; (2) a subsequent tectonically-active, laterally-constrained clastic basin stage. These events are interpreted to represent rapid filling of a thrust-block bounded "ramp valley" basin by sediments derived from the uplift of the nearby Cordillera Central, coincident with activation of the Hispaniola restraining bend in the late Miocene.
The Azua Basin sequence is a 2500 m thick Miocene Pliocene regressive interval. Limestones and marls of the Sombrerito Formation, the lowermost unit, ranges from lower Miocene to lowermost upper ...Miocene. The turbidite sequence of the Trinchera Formation spans an interval from uppermost middle Miocene to lower Pliocene. Blue-green, neritic lower Pliocene siltstones of the Quita Coraza Formation overlie the Trinchera in the seaward part of the basin. Shallow-marine strata in the lower part of the Arroyo Blanco Formation range from uppermost Miocene to middle Pliocene.Principal Components Analysis of rich benthic foraminiferal faunas aided in the recognition of species associations. Positive loadings on Factor 1 define a bathyal-neritic boundary zone assemblage: Bolivina minima (0.88), Cassidulina norcrossi var. australis (0.73), and Gyroidina regularis (0.71). Lower bathyal species Pleurostomella alternans (-0.64), Bolivina paula -0.62), and Cibicides wuellerstorfi (-0.49) show strong negative loadings. Positive loadings on Factor 2 define a middle to upper bathyal assemblage: Oridorsalis umbonatus (0.68), Hoeglundina elegans (0.57), and Uvigerina peregrina (0.51). Factor 3 represents a middle to outer neritic assemblage that includes Angulogerina jamaicensis (0.83), Cassidulina carinata (0.54), and Cibicidoides pachyderma forma sublittoralis (0.51). Factor 4 has heavy loadings on inner neritic species including Haynesina depressula (0.74), and Buliminella elegantissima (0.73). Neritic species associated with Factor 5 include Cancris sagra (0.69) and Bolivina lowmani (0.59). Plots of the factor scores in the stratigraphic sections demonstrate shoaling upward from lower bathyal to inner neritic depths. Cluster analysis reveals seven major sample groupings that correspond almost directly to the faunal zones identified in the Azua Basin by Bermudez (1949).Migration of foraminiferal environments toward the Caribbean during the Miocene and Pliocene is paralleled by time-transgression of lithofacies. The southwestern Dominican Republic evolved in two stages: (1) a tectonically quite open ocean stage before the late Miocene; (2) a subsequent tectonically-active, laterally-constrained clastic basin stage. These events are interpreted to represent rapid filling of a thrust-block bounded "ramp valley" basin by sediments derived from the uplift of the nearby Cordillera Central, coincident with activation of the Hispaniola restraining bend in the late Miocene.
The biologic and clinical heterogeneity of the various subtypes of non-Hodgkin's lymphoma is related to differences in morphologic, immunologic, and kinetic properties. Comprehensive studies ...characterizing these features in lymphomatous effusion have yet to be reported. We recently studied 27 effusion specimens from 26 patients with clinically suspected or confirmed lymphoma. Wright-Giemsa- and Papanicolaou-stained cytologic preparations, acridine orange nucleic acid flow cytometry, and immunoperoxidase staining of cell suspensions using antibodies to a battery of T and B cell markers were evaluated and compared with prior histologic accessions. Specimens were classified by cytologic characteristics according to the International Working Formulation Scheme and by acridine orange nucleic acid flow cytometry using the parameters of DNA, RNA, and proliferative activity. Correlation of the cytometric and morphologic data demonstrated that with increasing cytologic grade of lymphoma, the proliferative activity increased progressively and distinguished between grades (P less than 0.01). Immunologic studies identified B cell phenotype in 16 specimens, T cell in three, and true histiocytic lymphoma in one; one lymphoma had no cell markers (null cell). Six effusions proved to be inflammatory and reactive according to surface marker studies. Classification by cytologic characteristics showed good correlation with histologic classification performed previously. Immunologic study of cytologic specimens gave results identical to those achieved by frozen-section immunohistologic examination. Thus, immunologic and cytometric parameters can be readily performed on effusion specimens and aid in the diagnosis and classification of lymphomas.
The role of property in fostering good governance, robust economies, and strong civil societies has received fresh attention in the wake of the collapse of communism, the adoption of a market driven ...approach to the economy, and the increasing impact of information technology. Some of these reforms have focused on a diverse package of measures dealing with land tenure security, land and property transactions, and access to credit. They have also been concerned with supporting physical planning, the sustainable management and control of land use and of natural resources, and facilitating real property taxation. As well, there has been a growing awareness of the requirement to address such issues as the protection of the environment and the provision of land for all people whatever their gender, but especially for the poor and ethnic minorities. Land Administration provides a high level overview of recent advances in building formal property systems throughout the world and reviews the role of property in advancing a society's economic and social agenda. It undertakes an in-depth examination of the land administration infrastructure required to support these modern property systems, giving particular attention to the survey, registration, valuation, and land use control functions. The text also provides an extended discussion of the information management challenges associate with the land administration field.
The cardiac effects of positive end expiratory pressure (PEEP) were examined in 50 patients six hours after elective coronary bypass surgery. Increasing the level of PEEP from 5 to 10 to 15 cm H2O ...decreased cardiac index (evaluated by thermodilution), stroke index and left ventricular end diastolic volume index without a change in left ventricular ejection fraction (evaluated by nuclear ventriculography). Right ventricular end diastolic volume index remained unchanged. Coronary sinus blood flow (measured by the continuous thermodilution technique) and myocardial oxygen and lactate consumption were unchanged with the application of 15 cm H2O PEEP. In 21 patients, volume loading (250 ml mL of plasma) was performed at 5 cm, and again at 15 cm H2O PEEP. Volume loading produced a similar increase in cardiac volumes and cardiac index at 5 and 15 cm H2O PEEP. Right and left ventricular performance and left ventricular systolic function were not altered by PEEP (by analyses of covariance). Coronary sinus blood flow and myocardial oxygen consumption increased with volume loading at 5 and 15 cm H2O of PEEP, but myocardial lactate utilization tended to increase at 5 cm, and decrease at 15 cm H2O PEEP (p = 0.08). Of the 33 patients who underwent complete hemodynamic and metabolic measurements, 16 increased cardiac lactate utilization at 15 cm H2O PEEP and 17 decreased cardiac lactate utilization at 15 cm H2O PEEP. PEEP decreased cardiac index, perhaps by reducing left but not right ventricular volumes. Volume loading during PEEP restored cardiac index and revealed no depression in myocardial performance or systolic function. With the application of PEEP, myocardial metabolism was maintained in half the patients, but ischemic metabolism was observed in the other half.
We claim that much of the confusion associated with the "tautology problem" about survival of the fittest is due to the mistake of attributing fitness to individuals instead of to types. We argue ...further that the problem itself cannot be solved merely by taking fitness as the aggregate cause of reproductive success. We suggest that a satisfying explanation must center not on logical analysis of the concept of general adaptedness but on the empirical analysis of single adapted traits and their causal relationship to changes in allele frequencies.
The effects of nasal continuous positive airway pressure (CPAP) were examined during cardiac catheterization in 22 patients with congestive heart failure (CHF). CPAP was applied at a level of 5 cm ...H2O pressure. Hemodynamic measurements were made at baseline and while on CPAP. We hypothesized that patients with high left ventricular (LV) diastolic pressures would experience an increase in cardiac index (CI). To test this hypothesis, patients were divided into two groups based on their baseline pulmonary capillary wedge pressure (PCWP): one group of 11 whose PCWP was greater than or equal to 12 mm Hg (high-PCWP group) and a second group of 11 whose PCWP was less than 12 mm Hg (low-PCWP group). Among the high-PCWP group (mean PCWP +/- SEM = 19.0 +/- 2.7 mm Hg), CI rose significantly while on CPAP (from 2.48 +/- 0.26 to 2.82 +/- 0.26 L/min/m2, p less than 0.01). Stroke volume index (SVI) also rose significantly (from 52.6 +/- 7.0 to 64.1 +/- 8.0 ml/m2, p less than 0.001). In contrast, among the low-PCWP group (PCWP = 8.3 +/- 0.6 mm Hg), CI decreased significantly while on CPAP (from 3.14 +/- 0.44 to 2.89 +/- 0.62 ml/m2, p less than 0.025). SVI fell but not significantly while on CPAP (from 75.5 +/- 8.4 to 74.2 +/- 8.5 ml/m2). Multiple stepwise linear regression analysis revealed that the only significant correlate of the magnitude of change in CI in response to CPAP was baseline PCWP (r = 0.50, p less than 0.02).
Patients with early-staged Hodgkin's disease have had a higher relapse rate following radiotherapy alone if they have B symptoms, large mediastinal masses, hilar involvement, or stage III disease. ...From June 1988 to December 1989, 27 previously untreated patients with early-staged Hodgkin's disease with adverse features for disease-free survival received combined-modality therapy. Seventeen patients had stage I or II disease, 10 had stage III, 5 had B symptoms, 13 had large mediastinal masses, and 6 had peripheral masses measuring 10 cm or more in diameter. All patients initially received three cycles of a novel chemotherapeutic regimen combining Novantrone (mitoxantrone, American Cyanamid Company), vincristine, vinblastine, and prednisone (NOVP). Twenty-four patients with clinically staged I or II disease with adverse features or stage III disease did not undergo laparotomy; three patients had favorable stage I or II disease and at laparotomy had stage III disease. Radiotherapy-treatment fields depended on the extent of nodal involvement. Twenty-six patients completed all therapy as planned to complete remission (CR) and one of these has had progression; she is in second CR following additional radiotherapy. With a median follow-up of 12 months, all patients are alive. Tolerance to treatment was excellent with only grade 1 or 2 nausea, alopecia and myalgias, and brief myelosuppression. NOVP is an effective adjuvant chemotherapy regimen for inducing responses, with minimal toxicity, prior to definitive radiotherapy for patients with early-staged Hodgkin's disease.
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