p53 expression, DNA content and cell proliferation in primary and synchronous metastatic lesions from ovarian surface epithelial-stromal tumours

The aim of this study was to investigate biological heterogeneity between primary and metastatic ovarian cancer lesions from individual patients as a means of elucidating steps in clinical progression. Cancer tissue from 61 untreated patients with ovarian surface epithelial-stromal tumours was examined. p53 expression detected immunocytochemically by the PAb1801 antibody, DNA content evaluated by flow cytometry, and cell proliferation evaluated as the [3H]thymidine labelling index were investigated in primary tumours and corresponding synchronous metastases. The frequency of p53 positivity was similar in primary (62%) and metastatic (66%) sites, with an agreement between the two lesions from the same patient in 97% of the cases. Similarly, aneuploidy frequency (80%) and DNA indices were superimposable in primary and metastatic lesions from the same patient, with a 94% agreement. The frequency of aneuploidy was higher in p53-positive than in p53-negative lesions. An overall poor agreement (rs = 0.44) was observed for proliferative activity of primary and metastatic lesions, due to a heterogeneous profile in omental with respect to primary tumours, which was mainly evident in p53-positive cancers. Conversely, cell proliferation of peritoneal, abdominal and pelvic lesions was qualitatively similar to that of the primary tumour in 88% of patients.     

Evaluation of automated methods of measuring hemoglobin and hematocrit in horses

OBJECTIVE: To evaluate the accuracy of 3 automated methods of determining Hct and hemoglobin (Hb) concentration, compared with manual methods. Animals-22 clinically normal adult horses of various breeds. PROCEDURE: A blood sample was obtained from each horse. Six dilutions (representing Hct of 0, 10, 20, 40, 60, or 70%) were prepared from each sample and analyzed, using 1 of 2 blood gas analyzers or a hemoximeter (for automated determinations) or the Wintrobe macrohematocrit and cyanmethemoglobin methods (for manual determinations). Regression analysis was used to determine mean slope relationships between Hct and Hb measurements obtained by use of manual versus automated methods. Slopes were compared, using Student's t-test. RESULTS: Of the 3 automated methods examined, only 1 blood gas analyzer reported Hct and Hb values that were not significantly different from those determined by use of manual methods; however, this analyzer could not report Hb concentrations below 2.5 g/dl. The other blood gas analyzer reported values for Hct and Hb concentrations that were consistently higher than those obtained by use of manual methods at Hct < or = 20% and Hb < or = 6.6 g/dl. The hemoximeter yielded more accurate results if the Hb concentration was between 6.6 and 20 g/dl. CONCLUSION: Although there were some limitations in measuring at low Hb concentrations, the method of determining Hb concentration and Hct with blood gas analyzer 2 was more accurate than that with blood gas analyzer 1 (Hct and Hb concentration) or the hemoximeter (Hb only).     

Linear array of coaxially fed monopole elements in a parallel-platewaveguide. II. Experiment

For pt.I see ibid., vol.36, no.4, 1988. A 30-element linear array of coaxially fed equispaced monopoles in a parallel-plate waveguide, and a one-element and two half-element waveguide simulators were constructed. The experimental effort is described. Measured data is presented for the active impedance, coupling coefficients, and element patterns for the arrays of coaxially fed monopoles radiating into the semi-infinite parallel-plate region. Measurements of active impedance, coupling (scattering) coefficients, and element patterns show an excellent agreement with the theoretically predicted results     

Asymptotic analysis of mutual coupling in concave circularcylindrical arrays. II. Near-zone

For pt.I, see ibid., vol.41, no.2, p.121-36 (1993). This work evaluates the near-zone coupling coefficients in large concave arrays. A canonical model of a circular cylindrical concave array of open-ended rectangular waveguides is analyzed. It is shown that in the paraxial region (which also includes the area close to the excited element) the coupling coefficients are identical, to lowest asymptotic order, to those in an equivalent infinite planar array. In the transition region, which lies between the paraxial and the far zone, or the ray region, two representations were developed: one, a transition function, expressed in terms of a canonical integral which must be numerically evaluated, and the other a uniform representation, which consists of a superposition of a planar array contribution and a few periodic structure rays. The uniform representation is valid in the near zone (which includes both the paraxial and the transition region) as well as in the far zone. This form is simple and may be immediately generalized to concave arrays with slowly varying curvature and periodicity     

Element pattern of an axial dipole in a cylindrical phased array, Part II: Element design and experiments

The design and construction of a cylindrical array of axial dipoles is described. Dipole pattern amplitude measurements performed over practical scan and frequency ranges show excellent agreement with theoretically predicted results. Dipole pattern phase, feed line effects and radiator match are also discussed. These results provide strong evidence of the correctness of the analysis and numerical results presented in Part I of this paper, and furnish a firm basis for accurate prediction of array performance.     

Scaling access to heterogeneous data sources with DISCO

Accessing many data sources aggravates problems for users of heterogeneous distributed databases. Database administrators must deal with fragile mediators, that is, mediators with schemas and views that must be significantly changed to incorporate a new data source. When implementing translators of queries from mediators to data sources, database implementers must deal with data sources that do not support all the functionality required by mediators. Application programmers must deal with graceless failures for unavailable data sources. Queries simply return failure and no further information when data sources are unavailable for query processing. The Distributed Information Search COmponent (Disco) addresses these problems. Data modeling techniques manage the connections to data sources, and sources can be added transparently to the users and applications. The interface between mediators and data sources flexibly handles different query languages and different data source functionality. Query rewriting and optimization techniques rewrite queries so they are efficiently evaluated by sources. Query processing and evaluation semantics are developed to process queries over unavailable data sources. In this article, we describe: 1) the distributed mediator architecture of Disco; 2) the data model and its modeling of data source connections; 3) the interface to underlying data sources and the query rewriting process; and 4) query processing semantics. We describe several advantages of our system     

Dynamic Query Operator Scheduling for Wide-Area Remote Access

Distributed databases operating over wide-area networks such as the Internet, must deal with the unpredictable nature of the performance of communication. The response times of accessing remote sources can vary widely due to network congestion, link failure, and other problems. In such an unpredictable environment, the traditional iterator-based query execution model performs poorly. We have developed a class of methods, called query scrambling, for dealing explicitly with the problem of unpredictable response times. Query scrambling dynamically modifies query execution plans on-the-fly in reaction to unexpected delays in data access. In this paper we focus on the dynamic scheduling of query operators in the context of query scrambling. We explore various choices for dynamic scheduling and examine, through a detailed simulation, the effects of these choices. Our experimental environment considers pipelined and non-pipelined join processing in a client with multiple remote data sources and delayed or possibly bursty arrivals of data. Our performance results show that scrambling rescheduling is effective in hiding the impact of delays on query response time for a number of different delay scenarios.     

Periodic structure ray method for analysis of coupling coefficientsin large concave arrays. II. Application

For pt.I see ibid., vol.37, no.11, p.1377 (1989). The periodic structure ray method (PSRM) for evaluation of coupling coefficients in large concave array was developed in part I. The PSRM is illustrated here by an example of a circular cylindrical concave array of rectangular waveguide elements for which a modal solution also exists. Excellent agreement in amplitude and phase between the modal and the ray solutions is found. The results show that the PSRM is efficient and converges rapidly     

Linear array of coaxially fed monopole elements in a parallel platewaveguide. I. Theory

The performance of a coaxially fed monopole element is analyzed for an infinite array environment in a parallel plate guide. The analysis takes into account the geometry of the coaxial feed. Expressions for active admittance, coupling coefficients, and element patterns are given