962 resultados para multiple choice questions (MCQs)
Resumo:
This paper combines the idea of a hierarchical distributed genetic algorithm with different inter-agent partnering strategies. Cascading clusters of sub-populations are built from bottom up, with higher-level sub-populations optimising larger parts of the problem. Hence higher-level sub-populations search a larger search space with a lower resolution whilst lower-level sub-populations search a smaller search space with a higher resolution. The effects of different partner selection schemes amongst the agents on solution quality are examined for two multiple-choice optimisation problems. It is shown that partnering strategies that exploit problem-specific knowledge are superior and can counter inappropriate (sub-) fitness measurements.
Resumo:
An indirect genetic algorithm for the non-unicost set covering problem is presented. The algorithm is a two-stage meta-heuristic, which in the past was successfully applied to similar multiple-choice optimisation problems. The two stages of the algorithm are an ‘indirect’ genetic algorithm and a decoder routine. First, the solutions to the problem are encoded as permutations of the rows to be covered, which are subsequently ordered by the genetic algorithm. Fitness assignment is handled by the decoder, which transforms the permutations into actual solutions to the set covering problem. This is done by exploiting both problem structure and problem specific information. However, flexibility is retained by a self-adjusting element within the decoder, which allows adjustments to both the data and to stages within the search process. Computational results are presented.
Resumo:
This paper combines the idea of a hierarchical distributed genetic algorithm with different inter-agent partnering strategies. Cascading clusters of sub-populations are built from bottom up, with higher-level sub-populations optimising larger parts of the problem. Hence higher-level sub-populations search a larger search space with a lower resolution whilst lower-level sub-populations search a smaller search space with a higher resolution. The effects of different partner selection schemes for (sub-)fitness evaluation purposes are examined for two multiple-choice optimisation problems. It is shown that random partnering strategies perform best by providing better sampling and more diversity.
Resumo:
This paper combines the idea of a hierarchical distributed genetic algorithm with different inter-agent partnering strategies. Cascading clusters of sub-populations are built from bottom up, with higher-level sub-populations optimising larger parts of the problem. Hence higher-level sub-populations search a larger search space with a lower resolution whilst lower-level sub-populations search a smaller search space with a higher resolution. The effects of different partner selection schemes amongst the agents on solution quality are examined for two multiple-choice optimisation problems. It is shown that partnering strategies that exploit problem-specific knowledge are superior and can counter inappropriate (sub-) fitness measurements.
Resumo:
Apesar de décadas de estudos, as opiniões são controversas. Não existe uma opinião comum entre os pesquisadores sobre o que é e como ocorre a motivação, a satisfação e a insatisfação no trabalho. As condições físicas dos serviços são um factor primordial para a motivação, satisfação ou insatisfação do trabalhador, assim como o tipo de liderança existente no mesmo. Ao longo da nossa história tem-se assistido a muitos exemplos de liderança, uns mais, outros menos eficazes. A satisfação no trabalho é um estado afectivo resultante da apreciação das características percebidas do trabalho e da organização. Neste contexto de mudanças na administração pública em geral e na área da saúde em particular, surge este estudo em contexto hospitalar, motivado pela necessidade de conhecer a satisfação dos enfermeiros de um Centro Hospitalar de Lisboa e a relação com algumas variáveis sócio demográficas. Optou-se pelo paradigma quantitativo, numa amostra de 122 inquiridos pertencentes a um grupo de profissionais de enfermagem de um Hospital Central de Lisboa. Para a elaboração da parte empírica utilizou-se o método por questionário de escolha múltipla. Os objectivos definidos: Objectivo Geral: perceber o nível de motivação/ satisfação dos enfermeiros relativamente à profissão ao serviço e à hierarquia. Objectivos específicos: Identificar o nível de satisfação/motivação dos enfermeiros dos serviços estudados relativamente à profissão, em função das variáveis sociodemográficas. - Caracterizar os aspectos com os quais os enfermeiros têm maior e menor satisfação relacionados com a profissão, serviço e hierarquia. - Identificar se existe relação entre o nível de motivação/satisfação e os sintomas físicos sentidos. Os participantes da amostra são, maioritariamente do sexo feminino, a média de idades é de 32 anos, grande percentagem já tem como habilitações profissionais a licenciatura, têm entre 1 e 28 anos de profissão e 1 e 28 anos no serviço actual, 17,2% exercem funções de chefia. Grande percentagem da amostra tem como horário semanal de trabalho 35 horas e trabalham em horário rotativo. Os enfermeiros são profissionais que mostram insatisfação relativamente à profissão e hierarquia e moderada satisfação relativamente aos serviços. A satisfação dos enfermeiros quanto à profissão altera-se de acordo com o horário de trabalho, vínculo à instituição e os sentimentos que os mesmos têm relativamente ao trabalho. A satisfação dos enfermeiros relativamente ao serviço altera-se consoante o tempo de profissão e com os sentimentos que os profissionais apresentam relativamente ao trabalho. Quanto à satisfação dos enfermeiros relativamente à hierarquia altera-se dependendo da idade dos profissionais, do tempo de profissão e do serviço onde desempenham. Relativamente à satisfação geral com o trabalho, esta pode alterar dependendo da idade, do tempo de profissão, do serviço onde desempenham funções e dos sentimentos dos profissionais relativamente ao trabalho. De salientar que ao analisarmos os serviços estudados separadamente concluímos que os enfermeiros do serviço de urgência são profissionais muito insatisfeitos com a hierarquia e os enfermeiros da Unidade de Urgência Médica são profissionais pouco satisfeitos, mas apesar de tudo satisfeitos com a hierarquia. ABSTRACT; Behind decades of studies, the opinions are controversial. There is a common opinion among researchers about what is and how is the motivation, satisfaction and dissatisfaction at work. The physical conditions of services are a major factor in motivation, satisfaction or dissatisfaction of the worker and the type of leadership exists in it. Throughout our history have seen many examples of leadership, some more, some less effective. Job satisfaction is an affective state resulting from the assessment of the perceived characteristics of work and organization. ln this context of changes in public administration in general and in health in particular, this study appears in the hospital setting, motivated by the need to know the satisfaction of nurses in a Hospital in Lisbon and the relationship with sociodemographic variables. We chose the quantitative paradigm in a sample of 122 respondents belonging to a group of nursing professionals in a central hospital in Lisbon. ln developing the empirical part we used the method for multiple-choice test. The objectives: General Objective: To understand the level of motivation I satisfaction of nurses for the profession and the service hierarchy. Specific objectives: To identify the level of satisfaction I motivation of nursing service studied for the profession, according to the socio-demographic variables. - Characterize the points with which nurses have the highest and lowest satisfaction related to the profession, service and hierarchy. - To identify if there is a relationship between the level of motivation I satisfaction and physical symptoms felt. The sample participants are mostly female, average age is 32 years, a large percentage already has the professional qualifications of the degree, are between and 28 years of occupation and 1 and 28 in the current service, 17.2 % hold positions of leadership. A great percentage of the sample has the working week and working 35 hours on rotating schedule. Nurses are professionals who show dissatisfaction with the profession and the hierarchy and moderately satisfied for the services, the latter fact can be justified by what is possible when the organization professionals are available and perform functions in service to their liking and they like to work. The satisfaction of nurses as the profession changes according to working hours, commitment to the institution and the feelings they have for the work. The satisfaction of nurses for the service changes depending on the length of service and with the feelings that professionals are on the job. The satisfaction of nurses from the hierarchy will change depending on the age of professionals, time and professional service where they play. For the overall satisfaction with the work, this may change depending on age, length of employment, where the service functions and the feelings of the professionals for the job. Note that when analyzing the services studied separately concluded that the nurses in the emergency department professionals are very unhappy with the hierarchy and the nurses of the Unit of Emergency Medical professionals are somewhat satisfied but still happy
Resumo:
Students with specific learning disabilities (SLD) typically learn less history content than their peers without disabilities and show fewer learning gains. Even when they are provided with the same instructional strategies, many students with SLD struggle to grasp complex historical concepts and content area vocabulary. Many strategies involving technology have been used in the past to enhance learning for students with SLD in history classrooms. However, very few studies have explored the effectiveness of emerging mobile technology in K-12 history classrooms. ^ This study investigated the effects of mobile devices (iPads) as an active student response (ASR) system on the acquisition of U.S. history content of middle school students with SLD. An alternating treatments single subject design was used to compare the effects of two interventions. There were two conditions and a series of pretest probesin this study. The conditions were: (a) direct instruction and studying from handwritten notes using the interactive notebook strategy and (b) direct instruction and studying using the Quizlet App on the iPad. There were three dependent variables in this study: (a) percent correct on tests, (b) rate of correct responses per minute, and (c) rate of errors per minute. ^ A comparative analysis suggested that both interventions (studying from interactive notes and studying using Quizlet on the iPad) had varying degrees of effectiveness in increasing the learning gains of students with SLD. In most cases, both interventions were equally effective. During both interventions, all of the participants increased their percentage correct and increased their rate of correct responses. Most of the participants decreased their rate of errors. ^ The results of this study suggest that teachers of students with SLD should consider a post lesson review in the form of mobile devices as an ASR system or studying from handwritten notes paired with existing evidence-based practices to facilitate students’ knowledge in U.S. history. Future research should focus on the use of other interactive applications on various mobile operating platforms, on other social studies subjects, and should explore various testing formats such as oral question-answer and multiple choice. ^
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Objectives: Serra da Estrela native (SEN) breed of sheep is one of the most important in Portugal, standing responsible for the production of one of the most internationally recognized cheeses in the world, "Queijo Serra da Estrela” (protected designation of origin). One of the major risks to the sustainability of SEN dairy flocks if footrot, an infectious diseases that causes lameness, decrease in milk production, weight loss and decrease in fertility. The aim of this work was to determine which parameters become decisive for the appearance of footrot in SEN dairy flocks, while establishing associations with environmental and nutritional variables. Materials and Methods: The present study was carried out by performing an especially designed 27 multiple choice questionnaire, based on the underlying causes of lameness in livestock and in the clinical diagnosis performed by the vet techinichian of the clinical cases evaluated at the moment of the inquiry. The survey was performed during the execution of the oficial veterinary health program between February and September of 2014 by a veterinarian team from the Association of SEN Sheep Breeders (ANCOSE). The ovine producers (N=30, with a total of 1270 animals) were randomly selected from the extense area of production of “Queijo Serra da Estrela”. The parameters evaluated in the study were: season and consequent weather changes during the period of the study, floor types, hygiene conditions, bed types, the existence and use of footbaths, location of footbaths, foot trimming and foot hygiene procedures. After the construction of the database and using the Statistical Package for Social Sciences version 16.0 the frequency response for each item was calculated. Results: All SEN livestock producers are proactive in the treatment of lameness (70%). About 99.7% of lameness was related with footroot and most appeared in winter (36.7%). In some occasions there was not a specific season distribution (56.7% rainiest years). From the analyzed farms, 70% use straw as a floor bed, followed by bush (21%). 45.6% of animals were clinically diagnosed with footrot and were sheltered in straw floor. Bed quality is good in 40%, however frequent changes in the floor bed in the preceding 15 days had a higher rate of footroot diagnosed cases (33,23%) compared to monthly changes. Regarding sheepfold animal number, the distribution is proper in 36.7%, elevated in 30%, overcrowded in 6.7% and low in 23.3%. Clinically ill diagnosed animals in last category were the lowest observed (3%). Concerning hoof trimming, 76.7% trims while 23.3% reported not to perform that task. From those that perform trimming, 73.9% do it only when necessary, 21.7% at the time of clipping and 4.4% when the animal is affected. One curious result was that animals who perform trimming at clipping had higher footrot cases (52.6%), unlike those who trim only when necessary (40.2%) or even when animals are clinically ill (0.91%). Mostly all in the presence of footrot choose a local treatment (95.2%) using antibiotic sprays, instead of parenteral antibiotic treatment. Footbath is rarely used in the prevention (13.3%) of this disease and when it is misconceived (25%) and incorrectly formulated (100%). Conclusions: This study was the first performed in Portugal focusing footrot caracterization in native SEN flocks.Economic impact in SEN dairy flocks is atributed to factors such as direct decrease in milk and meat production,early slaughter of affected animals due to non responsive treatment and medical expenses.The most effective eradication method combines first of all the ability to understand the problems of SEN producers and implementation of preventive measures and treatment of footrot.Often linked to lack of formation, the advance age of portuguese producers the mentality and social factors block the advance of veterinarian intervention itself.
Resumo:
Objectives: Serra da Estrela native (SEN) breed of sheep is one of the most important in Portugal, standing responsible for the production of one of the most internationally recognized cheeses in the world, "Queijo Serra da Estrela” (protected designation of origin). One of the major risks to the sustainability of SEN dairy flocks if footrot, an infectious diseases that causes lameness, decrease in milk production, weight loss and decrease in fertility.The aim of this work was to determine which parameters become decisive for the appearance of footrot in SEN dairy flocks, while establishing associations with environmental and nutritional variables. Materials and methods: The present study was carried out by performing an especially designed 27 multiple choice questionnaire, based on the underlying causes of lameness in livestock and in the clinical diagnosis performed by the vet techinichian of the clinical cases evaluated at the moment of the inquiry. The survey was performed during the execution of the oficial veterinary health program between February and September of 2014 by a veterinarian team from the Association of SEN Sheep Breeders (ANCOSE). The ovine producers (N=30, with a total of 1270 animals) were randomly selected from the extense area of production of “Queijo Serra da Estrela”. The parameters evaluated in the study were: season and consequent weather changes during the period of the study, floor types, hygiene conditions, bed types, the existence and use of footbaths, location of footbaths, foot trimming and foot hygiene procedures. After the construction of the database and using the Statistical Package for Social Sciences version 16.0 the frequency response for each item was calculated. Results: All SEN livestock producers are proactive in the treatment of lameness (70%). About 99.7% of lameness was related with footroot and most appeared in winter (36.7%). In some occasions there was not a specific season distribution (56.7% rainiest years). From the analyzed farms, 70% use straw as a floor bed, followed by bush (21%). 45.6% of animals were clinically diagnosed with footrot and were sheltered in straw floor. Bed quality is good in 40%, however frequent changes in the floor bed in the preceding 15 days had a higher rate of footroot diagnosed cases (33,23%) compared to monthly changes. Regarding sheepfold animal number, the distribution is proper in 36.7%, elevated in 30%, overcrowded in 6.7% and low in 23.3%. Clinically ill diagnosed animals in last category were the lowest observed (3%). Concerning hoof trimming, 76.7% trims while 23.3% reported not to perform that task. From those that perform trimming, 73.9% do it only when necessary, 21.7% at the time of clipping and 4.4% when the animal is affected. One curious result was that animals who perform trimming at clipping had higher footrot cases (52.6%), unlike those who trim only when necessary (40.2%) or even when animals are clinically ill (0.91%). Mostly all in the presence of footrot choose a local treatment (95.2%) using antibiotic sprays, instead of parenteral antibiotic treatment. Footbath is rarely used in the prevention (13.3%) of this disease and when it is misconceived (25%) and incorrectly formulated (100%). Conclusion: This study is the first performed in Portugal focusing on footrot caracterization in native SEN flocks. The economic impact in SEN dairy flocks is atributed to factors such as the direct decrease in milk and meat production, the early slaughter of affected animals due to a non responsive treatment, and medical expenses. The most effective eradication method combines first of all the ability to understand the problems of SEN producers and then the implementation of preventive measures and treatment of footrot. Often linked to the lack of formation, and the advanced age of portuguese producers, the mentality and social factors block the advance of veterinarian intervention itself.
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In the field of educational and psychological measurement, the shift from paper-based to computerized tests has become a prominent trend in recent years. Computerized tests allow for more complex and personalized test administration procedures, like Computerized Adaptive Testing (CAT). CAT, following the Item Response Theory (IRT) models, dynamically generates tests based on test-taker responses, driven by complex statistical algorithms. Even if CAT structures are complex, they are flexible and convenient, but concerns about test security should be addressed. Frequent item administration can lead to item exposure and cheating, necessitating preventive and diagnostic measures. In this thesis a method called "CHeater identification using Interim Person fit Statistic" (CHIPS) is developed, designed to identify and limit cheaters in real-time during test administration. CHIPS utilizes response times (RTs) to calculate an Interim Person fit Statistic (IPS), allowing for on-the-fly intervention using a more secret item bank. Also, a slight modification is proposed to overcome situations with constant speed, called Modified-CHIPS (M-CHIPS). A simulation study assesses CHIPS, highlighting its effectiveness in identifying and controlling cheaters. However, it reveals limitations when cheaters possess all correct answers. The M-CHIPS overcame this limitation. Furthermore, the method has shown not to be influenced by the cheaters’ ability distribution or the level of correlation between ability and speed of test-takers. Finally, the method has demonstrated flexibility for the choice of significance level and the transition from fixed-length tests to variable-length ones. The thesis discusses potential applications, including the suitability of the method for multiple-choice tests, assumptions about RT distribution and level of item pre-knowledge. Also limitations are discussed to explore future developments such as different RT distributions, unusual honest respondent behaviors, and field testing in real-world scenarios. In summary, CHIPS and M-CHIPS offer real-time cheating detection in CAT, enhancing test security and ability estimation while not penalizing test respondents.
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Nowadays the idea of injecting world or domain-specific structured knowledge into pre-trained language models (PLMs) is becoming an increasingly popular approach for solving problems such as biases, hallucinations, huge architectural sizes, and explainability lack—critical for real-world natural language processing applications in sensitive fields like bioinformatics. One recent work that has garnered much attention in Neuro-symbolic AI is QA-GNN, an end-to-end model for multiple-choice open-domain question answering (MCOQA) tasks via interpretable text-graph reasoning. Unlike previous publications, QA-GNN mutually informs PLMs and graph neural networks (GNNs) on top of relevant facts retrieved from knowledge graphs (KGs). However, taking a more holistic view, existing PLM+KG contributions mainly consider commonsense benchmarks and ignore or shallowly analyze performances on biomedical datasets. This thesis start from a propose of a deep investigation of QA-GNN for biomedicine, comparing existing or brand-new PLMs, KGs, edge-aware GNNs, preprocessing techniques, and initialization strategies. By combining the insights emerged in DISI's research, we introduce Bio-QA-GNN that include a KG. Working with this part has led to an improvement in state-of-the-art of MCOQA model on biomedical/clinical text, largely outperforming the original one (+3.63\% accuracy on MedQA). Our findings also contribute to a better understanding of the explanation degree allowed by joint text-graph reasoning architectures and their effectiveness on different medical subjects and reasoning types. Codes, models, datasets, and demos to reproduce the results are freely available at: \url{https://github.com/disi-unibo-nlp/bio-qagnn}.
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Conventional karyotyping detects anomalies in 3-15% of patients with multiple congenital anomalies and mental retardation (MCA/MR). Whole-genome array screening (WGAS) has been consistently suggested as the first choice diagnostic test for this group of patients, but it is very costly for large-scale use in developing countries. We evaluated the use of a combination of Multiplex Ligation-dependent Probe Amplification (MLPA) kits to increase the detection rate of chromosomal abnormalities in MCA/MR patients. We screened 261 MCA/MR patients with two subtelomeric and one microdeletion kits. This would theoretically detect up to 70% of all submicroscopic abnormalities. Additionally we scored the de Vries score for 209 patients in an effort to find a suitable cut-off for MLPA screening. Our results reveal that chromosomal abnormalities were present in 87 (33.3%) patients, but only 57 (21.8%) were considered causative. Karyotyping detected 15 abnormalities (6.9%), while MLPA identified 54 (20.7%). Our combined MLPA screening raised the total detection number of pathogenic imbalances more than three times when compared to conventional karyotyping. We also show that using the de Vries score as a cutoff for this screening would only be suitable under financial restrictions. A decision analytic model was constructed with three possible strategies: karyotype, karyotype + MLPA and karyotype + WGAS. Karyotype + MLPA strategy detected anomalies in 19.8% of cases which account for 76.45% of the expected yield for karyotype + WGAS. Incremental Cost Effectiveness Ratio (ICER) of MLPA is three times lower than that of WGAS, which means that, for the same costs, we have three additional diagnoses with MLPA but only one with WGAS. We list all causative alterations found, including rare findings, such as reciprocal duplications of regions deleted in Sotos and Williams-Beuren syndromes. We also describe imbalances that were considered polymorphisms or rare variants, such as the new SNP that confounded the analysis of the 22q13.3 deletion syndrome. (C) 2011 Elsevier Masson SAS. All rights reserved.
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INTRODUCTION. Multiple sclerosis (MS) is a disabling disease occurring mainly in women of childbearing age. MS may interfere with family planning and motherhood decision. AIM. To study the influence of MS diagnosis and course of the disease on motherhood decision. PATIENTS AND METHODS. The cohort of 35 to 45-year-old female patients diagnosed with MS for at least ten years was selected from six Portuguese MS centers. A structured questionnaire was applied to all patients in consecutive consultation days. Clinical records were reviewed to characterize and collect information about the disease and pregnancies. RESULTS. One hundred women were included; mean age at MS diagnosis was 26.3 ± 5.0 years; 90% of the participants presented with a relapsing-remitting MS; 57% had no pregnancies after the diagnosis. MS type and number of relapses were not significantly different between women with or without pregnancies after the diagnosis (p = 0.39 and p = 0.50, respectively). Seventy-seven percent of the patients did not have the intended number of pregnancies. Main reasons given were fear of future disability and the possibility of having relapses. Forty-three women considered that pregnancy might worsen MS. CONCLUSION. In our population, motherhood choice was unrelated to the MS type and the number of relapses. However, a relevant number of women had fewer pregnancies than those intended before MS diagnosis and believed that pregnancy could worsen the disease. An effort to better inform the patients should be made to minimize the impact of MS diagnosis on motherhood decision.
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Questions: A multiple plot design was developed for permanent vegetation plots. How reliable are the different methods used in this design and which changes can we measure? Location: Alpine meadows (2430 m a.s.l.) in the Swiss Alps. Methods: Four inventories were obtained from 40 m(2) plots: four subplots (0.4 m(2)) with a list of species, two 10m transects with the point method (50 points on each), one subplot (4 m2) with a list of species and visual cover estimates as a percentage and the complete plot (40 m(2)) with a list of species and visual estimates in classes. This design was tested by five to seven experienced botanists in three plots. Results: Whatever the sampling size, only 45-63% of the species were seen by all the observers. However, the majority of the overlooked species had cover < 0.1%. Pairs of observers overlooked 10-20% less species than single observers. The point method was the best method for cover estimate, but it took much longer than visual cover estimates, and 100 points allowed for the monitoring of only a very limited number of species. The visual estimate as a percentage was more precise than classes. Working in pairs did not improve the estimates, but one botanist repeating the survey is more reliable than a succession of different observers. Conclusion: Lists of species are insufficient for monitoring. It is necessary to add cover estimates to allow for subsequent interpretations in spite of the overlooked species. The choice of the method depends on the available resources: the point method is time consuming but gives precise data for a limited number of species, while visual estimates are quick but allow for recording only large changes in cover. Constant pairs of observers improve the reliability of the records.
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We examine the effect of unilateral and mutual partner selection in the context of prisoner's dilemmas experimentally. Subjects play simultaneously several finitely repeated two-person prisoner's dilemma games. We find that unilateral choice is the best system. It leads to low defection and fewer singles than with mutual choice. Furthermore, with the unilateral choice setup we are able to show that intendingdefectors are more likely to try to avoid a match than intending cooperators. We compare our results of multiple games with single game PD-experiments and find no difference in aggregate behavior. Hence the multiple game technique is robust and might therefore be an important tool in the future for testing the use of mixed strategies.
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Ce mémoire examine les questions à mouvement multiple en bulgare, en accordant une importance particulière aux mécanismes qui régissent l’ordre des syntagmes interrogatifs antéposés. Outre la présentation d’un phénomène linguistique complexe et très intéressant, l’étude propose un aperçu critique des hypothèses les plus importantes émises au fil des ans à propos des interrogatives multiples. Dans un premier temps, nous discutons des différentes approches renfermant l’idée que l’ordre des mots interrogatifs au début de la proposition dépend entièrement des règles syntaxiques. Ensuite, nous présentons les analyses qui tentent d’expliquer la problématique en faisant appel à des traits spécifiques des syntagmes Qu-, tels que [animé] ou [lié au discours]. Le rôle de la topicalisation et de la focalisation dans la formation des questions multiples, les projections fonctionnelles de la « périphérie gauche » en bulgare accueillant différents syntagmes, ainsi que la résomption comptent également parmi les sujets traités dans ce mémoire.