Search results for " Embedding"
showing 10 items of 84 documents
Specific immunohistochemical identification of Candida albicans in paraffin-embedded tissue with a new monoclonal antibody (1B12).
1995
In invasive candidiasis, the identification of Candida organisms in tissue samples or in normally sterile fluids is essential for an accurate diagnosis. Species identification is an important clue for the source of infection and in epidemiological studies. In this article, the authors have tested the value of a new monoclonal antibody (1B12) to detect C albicans in culture by immunofluorescence, and in tissue samples by immunohistochemistry. MAb 1B12 was found to specifically recognize C albicans , does not cross-react with other Candida species or other structurally similar fungi, and is very sensitive and specific in paraffin-embedded tissue, having no reactivity in normal human tissues o…
Why do results conflict regarding the prognostic value of the methylation status in colon cancers? The role of the preservation method.
2012
Abstract Background In colorectal carcinoma, extensive gene promoter hypermethylation is called the CpG island methylator phenotype (CIMP). Explaining why studies on CIMP and survival yield conflicting results is essential. Most experiments to measure DNA methylation rely on the sodium bisulfite conversion of unmethylated cytosines into uracils. No study has evaluated the performance of bisulfite conversion and methylation levels from matched cryo-preserved and Formalin-Fixed Paraffin Embedded (FFPE) samples using pyrosequencing. Methods Couples of matched cryo-preserved and FFPE samples from 40 colon adenocarcinomas were analyzed. Rates of bisulfite conversion and levels of methylation of …
Efficient unsupervised clustering for spatial bird population analysis along the Loire river
2015
International audience; This paper focuses on application and comparison of Non Linear Dimensionality Reduction (NLDR) methods on natural high dimensional bird communities dataset along the Loire River (France). In this context, biologists usually use the well-known PCA in order to explain the upstream-downstream gradient.Unfortunately this method was unsuccessful on this kind of nonlinear dataset.The goal of this paper is to compare recent NLDR methods coupled with different data transformations in order to find out the best approach. Results show that Multiscale Jensen-Shannon Embedding (Ms JSE) outperform all over methods in this context.
Neural networks with non-uniform embedding and explicit validation phase to assess Granger causality
2015
A challenging problem when studying a dynamical system is to find the interdependencies among its individual components. Several algorithms have been proposed to detect directed dynamical influences between time series. Two of the most used approaches are a model-free one (transfer entropy) and a model-based one (Granger causality). Several pitfalls are related to the presence or absence of assumptions in modeling the relevant features of the data. We tried to overcome those pitfalls using a neural network approach in which a model is built without any a priori assumptions. In this sense this method can be seen as a bridge between model-free and model-based approaches. The experiments perfo…
Vectors of Pairwise Item Preferences
2019
Neural embedding has been widely applied as an effective category of vectorization methods in real-world recommender systems. However, its exploration of users’ explicit feedback on items, to create good quality user and item vectors is still limited. Existing neural embedding methods only consider the items that are accessed by the users, but neglect the scenario when a user gives high or low rating to a particular item. In this paper, we propose Pref2Vec, a method to generate vector representations of pairwise item preferences, users and items, which can be directly utilized for machine learning tasks. Specifically, Pref2Vec considers users’ pairwise item preferences as elementary units. …
Deep Networks for Collaboration Analytics : Promoting Automatic Analysis of Face-to-Face Interaction in the Context of Inquiry-Based Learning
2021
Scholars have applied automatic content analysis to study computer-mediated communication in computer-supported collaborative learning (CSCL). Since CSCL also takes place in face-to-face interactions, we studied the automatic coding accuracy of manually transcribed face-to-face communication. We conducted our study in an authentic higher-education physics context where computer-supported collaborative inquiry-based learning (CSCIL) is a popular pedagogical approach. Since learners’ needs for support in CSCIL vary in the different inquiry phases (orientation, conceptualization, investigation, conclusion, and discussion), we studied, first, how the coding accuracy of five computational models…
PCR testing for Treponema pallidum in paraffin-embedded skin biopsy specimens: test design and impact on the diagnosis of syphilis
2007
Background: Syphilis, a chronic infection caused by Treponema pallidum (T. pallidum), is a disease which is increasing in incidence, and thus more and more becoming a differential diagnosis in routine pathology. Aim: Since histological changes are not specific, we sought to develop a polymerase chain reaction (PCR)-based molecular assay for the detection of T. pallidum in formalin-fixed, paraffin-embedded tissues, and evaluate its diagnostic power, especially in comparison with other ancillary methods, i.e. immunohistochemistry and Dieterle staining. Methods: 36 skin biopsies with the clinical and /or serological diagnosis of syphilis were evaluated by morphology, immunohistochemistry and s…
Comparison of two PCR methods for detection of Leptospira interrogans in formalin-fixed and paraffin-embedded tissues
2012
In this study we compared two polymerase chain reaction (PCR) methods using either 16S ribosomal RNA (rRNA) or 23S rRNA gene primers for the detection of different Leptospira interrogans serovars. The performance of these two methods was assessed using DNA extracted from bovine tissues previously inoculated with several bacterial suspensions. PCR was performed on the same tissues before and after the formalin-fixed, paraffin-embedding procedure (FFPE tissues). The 23S rDNA PCR detected all fresh and FFPE positive tissues while the 16S rDNA-based protocol detected primarily the positive fresh tissues. Both methods are specific for pathogenic L. interrogans. The 23S-based PCR method successfu…
Sobolev embeddings, extensions and measure density condition
2008
AbstractThere are two main results in the paper. In the first one, Theorem 1, we prove that if the Sobolev embedding theorem holds in Ω, in any of all the possible cases, then Ω satisfies the measure density condition. The second main result, Theorem 5, provides several characterizations of the Wm,p-extension domains for 1<p<∞. As a corollary we prove that the property of being a W1,p-extension domain, 1<p⩽∞, is invariant under bi-Lipschitz mappings, Theorem 8.
Recombinant cDNA encapsulation in small liposomes with hepatocyte access ability.
1993
Liposomal encapsulation efficiency of a recombinant cDNA was studied by several procedures. We observed that supernatant fraction of ultracentrifuged liposomes prepared by extrusion through polycarbonate filters of 400 nm pore size yielded a very homogeneous suspension of small (50 nm diameter) unilamellar liposomes with highest DNA/lipid ratio and great ability to access to hepatocytes.