Artykuły naukowe (WMiI)Artykuły naukowe pracowników naukowych Wydziału Matematyki i Informatykihttps://hdl.handle.net/10593/712024-09-18T07:22:27Z2024-09-18T07:22:27Z181Performance of Selected Models for Predicting Malignancy in Ovarian Tumors in Relation to the Degree of Diagnostic Uncertainty by Subjective Assessment With UltrasoundSzubert, SebastianSzpurek, DariuszWójtowicz, AndrzejŻywica, PatrykStukan, MaciejSajdak, StefanJabłoński, SławomirWicherek, ŁukaszMoszyński, Rafałhttps://hdl.handle.net/10593/264012024-01-28T16:12:52Z2020-01-01T00:00:00Zdc.title: Performance of Selected Models for Predicting Malignancy in Ovarian Tumors in Relation to the Degree of Diagnostic Uncertainty by Subjective Assessment With Ultrasound
dc.contributor.author: Szubert, Sebastian; Szpurek, Dariusz; Wójtowicz, Andrzej; Żywica, Patryk; Stukan, Maciej; Sajdak, Stefan; Jabłoński, Sławomir; Wicherek, Łukasz; Moszyński, Rafał
dc.description.abstract: Objectives
The study's main aim was to evaluate the relationship between the performance of predictive models for differential diagnoses of ovarian tumors and levels of diagnostic confidence in subjective assessment (SA) with ultrasound. The second aim was to identify the parameters that differentiate between malignant and benign tumors among tumors initially diagnosed as uncertain by SA.
Methods
The study included 250 (55%) benign ovarian masses and 201 (45%) malignant tumors. According to ultrasound findings, the tumors were divided into 6 groups: certainly benign, probably benign, uncertain but benign, uncertain but malignant, probably malignant, and certainly malignant. The performance of the risk of malignancy index, International Ovarian Tumor Analysis assessment of different neoplasias in the adnexa model, and International Ovarian Tumor Analysis logistic regression model 2 was analyzed in subgroups as follows: SA-certain tumors (including certainly benign and certainly malignant) versus SA-probable tumors (probably benign and probably malignant) versus SA-uncertain tumors (uncertain but benign and uncertain but malignant).
Results
We found a progressive decrease in the performance of all models in association with the increased uncertainty in SA. The areas under the receiver operating characteristic curve for the risk of malignancy index, logistic regression model 2, and assessment of different neoplasias in the adnexa model decreased between the SA-certain and SA-uncertain groups by 20%, 28%, and 20%, respectively. The presence of solid parts and a high color score were the discriminatory features between uncertain but benign and uncertain but malignant tumors.
Conclusions
Studies are needed that focus on the subgroup of ovarian tumors that are difficult to classify by SA. In cases of uncertain tumors by SA, the presence of solid components or a high color score should prompt a gynecologic oncology clinic referral.
dc.description: Preprint artykułu
2020-01-01T00:00:00ZDescriptive Topology in non-Archimedean Function Spaces Cp(X, K). Part IŚliwa, WiesławKąkol, Jerzyhttps://hdl.handle.net/10593/43272021-01-15T18:22:08Z2012-01-01T00:00:00Zdc.title: Descriptive Topology in non-Archimedean Function Spaces Cp(X, K). Part I
dc.contributor.author: Śliwa, Wiesław; Kąkol, Jerzy
dc.description.abstract: Let $K$ be a non-archimedean field and let $X$ be an ultraregular space. We
study the non-archimedean locally convex space $C_p(X;K)$ of all $K$-valued continuous
functions on $X$ endowed with the pointwise topology. We show that $K$ is spherically
complete if and only if every polar metrizable locally convex space $E$ over $K$ is weakly
angelic. This extends a result of Kiyosawa - Schikhof for polar Banach spaces. For any
compact ultraregular space $X$ we prove that $C_p(X;K)$ is Frechet-Urysohn if and only if
$X$ is scattered (a non-archimedean variant of Gerlits - Pytkeev's result). If $K$ is locally
compact we show the following: (1) For any ultraregular space $X$ the space $C_p(X;K)$
is K-analytic if and only if it has a compact resolution (a non-archimedean variant of
Tkachuk's theorem); (2) For any ultrametrizable space $X$ the space $C_p(X;K)$ is analytic
if and only if $X$ is $\sigma$-compact (a non-archimedean variant of Christensen's theorem).
2012-01-01T00:00:00ZOn linear isometries on non-archimedean powerseries spacesŚliwa, WiesławZiemkowska, Agnieszkahttps://hdl.handle.net/10593/43242021-01-15T18:17:10Z2012-05-01T00:00:00Zdc.title: On linear isometries on non-archimedean powerseries spaces
dc.contributor.author: Śliwa, Wiesław; Ziemkowska, Agnieszka
dc.description.abstract: The non-archimedean power series spaces Ap(a; t) are the most
known and important examples of non-archimedean nuclear Frechet spaces. We
study when the spaces Ap(a; t) and Aq(b; s) are isometrically isomorphic. Next we
determine all linear isometries on the space Ap(a; t) and show that all these maps
are surjective.
2012-05-01T00:00:00ZFrechet spaces of non-archimedean valued continuous functionsŚliwa, Wiesławhttps://hdl.handle.net/10593/42982021-01-15T18:18:17Z2012-01-01T00:00:00Zdc.title: Frechet spaces of non-archimedean valued continuous functions
dc.contributor.author: Śliwa, Wiesław
dc.description.abstract: Let $X$ be an ultraregular space and let $K$ be a complete non-archimedean
non-trivially valued field. Assume that the locally convex space $E$ = $C_c(X;K)$
of all continuous functions from $X$ to $K$ with the topology of uniform
convergence on compact subsets of $X$ is a Frechet space. We shall prove that
$E$ has an orthogonal basis consisting of $K$-valued characteristic functions of
clopen (i.e. closed and open) subsets of $X$ and that it is isomorphic to the
product of a countable family of Banach spaces with an orthonormal basis.
2012-01-01T00:00:00ZThe separable quotient problem and the strongly normal sequencesŚliwa, Wiesławhttps://hdl.handle.net/10593/42972021-01-15T18:22:06Z2012-01-01T00:00:00Zdc.title: The separable quotient problem and the strongly normal sequences
dc.contributor.author: Śliwa, Wiesław
dc.description.abstract: We study the notion of a strongly normal sequence in the dual $E^*$ of
a Banach space $E$. In particular, we prove that the following three conditions are
equivalent:
(1) $E$ has a strongly normal sequence,
(2) $(E^*;\sigma (E ^*;E))$ has a Schauder basic sequence,
(3) $E$ has an infinite-dimensional separable quotient.
2012-01-01T00:00:00ZOn tame operators between non-archimedean power seris spacesŚliwa, WiesławZiemkowska, Agnieszkahttps://hdl.handle.net/10593/42962021-01-15T18:20:26Z2012-01-01T00:00:00Zdc.title: On tame operators between non-archimedean power seris spaces
dc.contributor.author: Śliwa, Wiesław; Ziemkowska, Agnieszka
dc.description.abstract: Let p {1∞}. We show that any continuous linear operator T from A1(a) to Ap(b) is tame i.e. there exists a positive integer c such that supx IITxIIk=/IxIck < ∞ for every k N. Next we prove that a similar result holds for operators from A∞(a) to Ap(b) if and only if the set Mba of all finite limit points of the double sequence (bj/ai/I,j N is bounded. Finally we show that the range of every tame operator from A∞(a) to A∞(b) has a Schauder basis.
2012-01-01T00:00:00ZOn the selection of basic orthogonal sequences in non-archimedean metrizable locally convex spacesŚliwa, Wiesławhttps://hdl.handle.net/10593/9412021-01-15T15:44:33Z2002-01-01T00:00:00Zdc.title: On the selection of basic orthogonal sequences in non-archimedean metrizable locally convex spaces
dc.contributor.author: Śliwa, Wiesław
dc.description.abstract: Our main result follows that any infinite-dimensional sub-space F of a non-archimedean metrizable locally convex space E with an or-
thogonal basis (e_n) contains a basic orthogonal sequence equivalent to a block
basic orthogonal sequence relative to (e_n). Hence any infinite-dimensional non-archimedean metrizable locally convex space F has a basic orthogonal sequence equivalent to a block basic orthogonal sequence
relative to an orthogonal basis in c_0^N.
2002-01-01T00:00:00ZOn the quasi-equivalence of orthogonal bases in non-archimedean metrizable locally convex spacesŚliwa, Wiesławhttps://hdl.handle.net/10593/9402021-01-15T15:45:02Z2002-01-01T00:00:00Zdc.title: On the quasi-equivalence of orthogonal bases in non-archimedean metrizable locally convex spaces
dc.contributor.author: Śliwa, Wiesław
dc.description.abstract: We prove that any non-archimedean metrizable locally convex space
E with a regular orthogonal basis has the quasi-equivalence property, i.e. any two
orthogonal bases in E are quasi-equivalent. In particular, the power series spaces, the most known and important examples of non-archimedean
nuclear Frechet spaces, have the quasi-equivalence property. We also show that the
Frechet spaces: K^N, c_0xK^N, c_0^N
have the quasi-equivalence property.
2002-01-01T00:00:00ZOn the stability of orthogonal bases in non-archimedean metrizable locally convex spacesŚliwa, Wiesławhttps://hdl.handle.net/10593/9392021-01-15T15:27:38Z2001-01-01T00:00:00Zdc.title: On the stability of orthogonal bases in non-archimedean metrizable locally convex spaces
dc.contributor.author: Śliwa, Wiesław
dc.description.abstract: It is proved that an orthogonal basis in a non-archimedean metrizable
locally convex space E (in particular, a Schauder basis in a non-archimedean
Frechet space E) is stable if and only if there is a continuous norm on E.
Many others results are also obtained.
2001-01-01T00:00:00ZClosed subspaces without Schauder bases in non-archimedean Frechet spacesŚliwa, Wiesławhttps://hdl.handle.net/10593/9262021-01-15T15:27:31Z2001-06-01T00:00:00Zdc.title: Closed subspaces without Schauder bases in non-archimedean Frechet spaces
dc.contributor.author: Śliwa, Wiesław
dc.description.abstract: Let E be an infinite-dimensional non-archimedean Frechet space which is not isomorphic to any of
the following spaces: $c_0,c_0 x K^N,K^N$. It is proved that E contains a closed subspace without a
Schauder basis (even without a strongly finite-dimensional Schauder decomposition). Conversely,
it is shown that any closed subspace of $c_0 x K^N$ has a Schauder basis.
2001-06-01T00:00:00Z