Ranka Stanković

Influence of initial treatment on the survival and recurrence in patients with differentiated thyroid microcarcinoma.

Purpose Differentiated thyroid microcarcinoma (DTM) has a good prognosis and survival, but recurrent disease may appear during follow-up. The aim of this study was to evaluate the influence of initial treatment including surgery and radioactive iodine (131I) on the survival and recurrence in patients with DTM. Methods Between January 1979 and December 2006, 130 patients with DTM were retrospectively evaluated, with a median follow-up of 10 years. Total/near-total thyroidectomy was performed in 121 (93.1%) of 130 patients, followed with 131I ablation in 71 (54.6%) of 130 patients. Results The probability of disease-specific survival was 97.7% ± 1.3% after 5 and 10 years; the probability of disease-specific survival was 95.9% ± 2.2% after 15, 20, 25, and 28 years after the initial treatment and was significantly influenced by recurrence, clinical stage, and patients’ age (P = 0.0001, P = 0.0005, and P = 0.02, respectively). Sex, histopathological type of the tumor, metastases at presentation, initial treatment, performance of radioactive therapy, and risk categories had no influence on survival (P = 0.8, P = 0.6, P = 0.1, P = 0.4, P = 0.5, and P = 0.1, respectively). The overall recurrence rate was 10.8%, (6.9% in lymph nodes, 1.5% in thyroid bed, and 2.3% at distant sites), with a median appearance time of 30 months. Recurrences were significantly influenced by regional metastases at presentation, radioiodine ablation, and initial treatment (P = 0.0002, P = 0.005, and P = 0.003, respectively); there was no relationship based on age, sex, histological type of the tumor, and tumor multifocality. Conclusions To perform more accurate surveillance for recurrence, total/near-total thyroidectomy followed by radioiodine ablation may be the optimal initial treatment for patients with DTM.

Automatic construction of a morphological dictionary of multi-word units

The development of a comprehensive morphological dictionary of multi-word units for Serbian is a very demanding task, due to the complexity of Serbian morphology. Manual production of such a dictionary proved to be extremely time-consuming. In this paper we present a procedure that automatically produces dictionary lemmas for a given list of multi-word units. To accomplish this task the procedure relies on data in e-dictionaries of Serbian simple words, which are already well developed. We also offer an evaluation of the proposed procedure on several different sets of data. Finally, we discuss some implementation issues and present how the same procedure is used for other languages.

Improvement of Queries using a Rule Based Procedure for Inflection of Compounds and Phrases

The selection of words chosen for a query, crucial for the quality of results obtained by the query, can be substantially improved by using various lexical resources. Thus, for example, morphological dictionaries enable morphological expansion of queries, which is very important in highly inflective languages, such as Serbian. This paper discusses issues related to improvement of queries using a rule based procedure implemented in WS4LR, a workstation for manipulating heterogeneous lexical resources developed by the Human Language Technology Group at the University of Belgrade. The procedure is used for automatic production of lemmas for a morphological dictionary from a given list of compounds, and its evaluation on several different sets of data is given. Several examples illustrate how this procedure can be used for improvement of queries for web search engines. Results obtained for these examples show that the number of documents obtained through a query by using our approach can be remarkably increased.

Improving Document Retrieval in Large Domain Specific Textual Databases Using Lexical Resources

Large collections of textual documents represent an example of big data that requires the solution of three basic problems: the representation of documents, the representation of information needs and the matching of the two representations. This paper outlines the introduction of document indexing as a possible solution to document representation. Documents within a large textual database developed for geological projects in the Republic of Serbia for many years were indexed using methods developed within digital humanities: bag-of-words and named entity recognition. Documents in this geological database are described by a summary report, and other data, such as title, domain, keywords, abstract, and geographical location. These metadata were used for generating a bag of words for each document with the aid of morphological dictionaries and transducers. Named entities within metadata were also recognized with the help of a rule-based system. Both the bag of words and the metadata were then used for pre-indexing each document. A combination of several \(tf\_idf\) based measures was applied for selecting and ranking of retrieval results of indexed documents for a specific query and the results were compared with the initial retrieval system that was already in place. In general, a significant improvement has been achieved according to the standard information retrieval performance measures, where the InQuery method performed the best.

Keyword-Based Search on Bilingual Digital Libraries

This paper outlines the main features of Biblisa, a tool that offers various possibilities of enhancing queries submitted to large collections of aligned parallel text residing in bilingual digital library. Biblisa supports keyword queries as an intuitive way of specifying information needs. The keyword queries initiated, in Serbian or English, can be expanded, both semantically, morphologically and in other language, using different supporting monolingual and bilingual resources. Terminological and lexical resources are of various types, such as wordnets, electronic dictionaries, SQL and NoSQL databases, which are distributed in different servers accessed in various ways. The web application has been tested on a collection of texts from 3 journals and 2 projects, comprising 299 documents generated from TMX, stored in a NoSQL database. The tool allows the full-text and metadata search, with extraction of concordance sentence pairs for translation and terminology work support.

Indexing of Textual Databases Based on Lexical Resources: A Case Study for Serbian

In this paper we describe an approach to improvement of information retrieval results for large textual databases by pre-indexing documents using bag-of-words and named entity recognition. The approach was applied on a database of geological projects financed by the Republic of Serbia for several decades now. Each document within this database is described by a summary report, consisting of metadata on the geological project, such as title, domain, keywords, abstract, and geographical location. A bag of words was produced from these metadata with the help of morphological dictionaries and transducers, while named entities were recognized using a rule-based system. Both were then used for pre-indexing documents for information retrieval purposes where ranking of retrieved documents was based on several

Using Lexical Resources for Irony and Sarcasm Classification

tf\_idf

Building learning capacity by blending different sources of knowledge

based measures. Evaluation of ranked retrieval results based on data obtained by pre-indexing were compared to results obtained by informational retrieval without pre-indexing with precision-recall curve, showing a significant improvement in terms of the mean average precision measure.