Application of multidetector computed tomography in the diagnosis of pulmonary embolism and new directions of development

Introduction: Pulmonary embolism (PE) is a condition involving the mechanical part of the closure of the pulmonary arterial thrombus or other embolic material. Is the third the most typical cardiovascular disease - vascular, immediately after a heart attack and stroke. Clinical symptoms are often nonspecific and may result in an incorrect diagnosis. The most common complications of PE include: attack the lungs, impaired heart function, superinfection and development of pulmonary hypertension. Objective: The purpose of the work was to discuss of the technical aspects and the use of multi-slice computed tomography in the diagnosis of PE. The presentation emphasized new directions of development of tomographic methods in imaging thromboembolic events of pulmonary arteries, including multi-energy CT and low-dose techniques. Description of the state of knowledge: Angiography-CT is currently the gold standard in the diagnosis of PE, especially in patients with high and indirect clinical risk. It is characterized by high sensitivity and specificity in contrast enhancement imaging defects within the pulmonary vasculature and blood changes in the pulmonary parenchyma, which may accompany the EP. It also allows to assess the features of right heart overload in the course of massive PE or radiological symptoms associated with the development of chronic PE. Summary: Nowadays, the greatest challenges of CT diagnostics in PE are the improvement of image quality, minimization of artifacts and reduction of the radiation dose to which the patient is exposed. Effective diagnosis of PE is not only good quality CT imaging, but also the efficiency of the process of diagnosis. Hence the development of new applications of CT - called. computer aided diagnosis (CAD)

Detection of gender-biased items in the peabody picture vocabulary test

This study investigated possible gender bias on a vocabulary test, using a method suggested by Andrich and Hagquist to detect "real" differential item functioning (DIF). A total of 443 adult ESL learners completed all 228 items of the Peabody Picture Vocabulary Test (PPVT-IV). The 310 female and 133 male participants were assumed to be of equal competence, corresponding to levels B1 and B2 on the Common European Framework of Reference for Languages. Male participants outscored female participants, possibly due to the multiple-choice format and to the fact that most gender-biased questions favored men rather than women. Finally, our analysis process yielded only seven items out of 228 as showing gender DIF, which is much lower than the numbers reported in the literature for ESL tests. This low figure suggests that the high number of gender-related DIF items reported in previous research might be attributed to the use of DIF detecting methods that do not take into account artificial DIF stemming from the cross-contamination of test item

Native vs. non-native English: data-driven lexical analysis

This article presents a preliminary, data-driven study of a corpus of texts written by advanced Polish learners of English, which were analysed with reference to a baseline corpus of native-speaker texts. The texts included in both corpora were produced in similar circumstances (classroom setting), with the same time and word limit, and in response to the same task. We conducted a comparative lexical analysis of the two corpora, using corpus methodology (word lists, cluster analysis, concordances, keyness) to identify the most significant differences. The most important conclusion from this study is that advanced foreign language use may differ from native-speaker language use in ways which only become visible in larger samples of language, and the differences, if analysed individually, would not be regarded as errors and would go unnoticed. There is some evidence in the study that some of these differences may be attributed to cross-linguistic influence

The handling of missing binary data in language research

Researchers are frequently confronted with unanswered questions or items on their questionnaires and tests, due to factors such as item difficulty, lack of testing time, or participant distraction. This paper first presents results from a poll confirming previous claims (Rietveld & van Hout, 2006; Schafer & Gra- ham, 2002) that data replacement and deletion methods are common in research. Language researchers declared that when faced with missing answers of the yes/no type (that translate into zero or one in data tables), the three most common solutions they adopt are to exclude the participant’s data from the analyses, to leave the square empty, or to fill in with zero, as for an incorrect answer. This study then examines the impact on Cronbach’s α of five types of data insertion, using simulated and actual data with various numbers of participants and missing percentages. Our analyses indicate that the three most common methods we identified among language researchers are the ones with the greatest impact on Cronbach's α coefficients; in other words, they are the least desirable solutions to the missing data problem. On the basis of our results, we make recommendations for language researchers concerning the best way to deal with missing data. Given that none of the most common simple methods works properly, we suggest that the missing data be replaced either by the item’s mean or by the participants’ overall mean to provide a better, more accurate image of the instrument’s internal consistency511531698Studies in Second Language Learning and Teaching