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Efficient Frequent Closed Itemset Algorithms With Applications To Stream Mining And ClassificationRanganath, B N 09 1900 (has links)
Data mining is an area to find valid, novel, potentially useful, and ultimately understandable abstractions in a data. Frequent itemset mining is one of the important data mining approaches to find those abstractions in the form of patterns. Frequent Closed itemsets provide complete and condensed information for non-redundant association rules generation. For many applications mining all the frequent itemsets is not necessary, and mining frequent Closed itemsets are adequate. Compared to frequent itemset mining, frequent Closed itemset mining generates less number of itemsets, and therefore improves the efficiency and effectiveness of these tasks.
Recently, much research has been done on Closed itemsets mining, but it is mainly for traditional databases where multiple scans are needed, and whenever new transactions arrive, additional scans must be performed on the updated transaction database; therefore, they are not suitable for data stream mining.
Mining frequent itemsets from data streams has many potential and broad applications. Some of the emerging applications of data streams that require association rule mining are network traffic monitoring and web click streams analysis. Different from data in traditional static databases, data streams typically arrive continuously in high speed with huge amount and changing data distribution. This raises new issues that need to be considered when developing association rule mining techniques for stream data.
Recent works on data stream mining based on sliding window method slide the window by one transaction at a time. But when the window size is large and support threshold is low, the existing methods consume significant time and lead to a large increase in user response time.
In our first work, we propose a novel algorithm Stream-Close based on sliding window model to mine frequent Closed itemsets from the data streams within the current sliding window. We enhance the scalabality of the algorithm by introducing several optimization techniques such as sliding the window by multiple transactions at a time and novel pruning techniques which lead to a considerable reduction in the number of candidate itemsets to be examined for closure checking. Our experimental studies show that the proposed algorithm scales well with large data sets.
Still the notion of frequent closed itemsets generates a huge number of closed itemsets in some applications. This drawback makes frequent closed itemsets mining infeasible in many applications since users cannot interpret the large volume of output (which sometimes will be greater than the data itself when support threshold is low) and may lead to an overhead to develop extra applications which post processes the output of original algorithm to reduce the size of the output.
Recent work on clustering of itemsets considers strictly either expression(consists of items present in itemset) or support of the itemsets or partially both to reduce the number of itemsets. But the drawback of the above approaches is that in some situations, number of itemsets does not reduce due to their restricted view of either considering expressions or support.
So we propose a new notion of frequent itemsets called clustered itemsets which considers both expressions and support of the itemsets in summarizing the output. We introduce a new distance measure w.r.t expressions and also prove the problem of mining clustered itemsets to be NP-hard.
In our second work, we propose a deterministic locality sensitive hashing based classifier using clustered itemsets. Locality sensitive hashing(LSH)is a technique for efficiently finding a nearest neighbour in high dimensional data sets. The idea of locality sensitive hashing is to hash the points using several hash functions to ensure that for each function the probability of collision is much higher for objects that are close to each other than those that are far apart. We propose a LSH based approximate nearest neighbour classification strategy. But the problem with LSH is, it randomly chooses hash functions and the estimation of a large number of hash functions could lead to an increase in query time. From Classification point of view, since LSH chooses randomly from a family of hash functions the buckets may contain points belonging to other classes which may affect classification accuracy. So, in order to overcome these problems we propose to use class association rules based hash functions which ensure that buckets corresponding to the class association rules contain points from the same class. But associative classification involves generation and examination of large number of candidate class association rules. So, we use the clustered itemsets which reduce the number of class association rules to be examined. We also establish formal connection between clustering parameter(delta used in the generation of clustered frequent itemsets) and discriminative measure such as Information gain. Our experimental studies show that the proposed method achieves an increase in accuracy over LSH based near neighbour classification strategy.
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Filtros digitais para a separação de subbandas em sistemas PLC baseados em clustered-OFDMSchettino, Hugo Viveiros 26 February 2016 (has links)
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Previous issue date: 2016-02-26 / Este trabalho investiga o uso de filtros digitais de resposta ao impulso finita (finite impulse response
- FIR) e de resposta ao impulso infinita (infinite impulse response - IIR) para separar
os sinais dos clusters de esquemas de multiplexação por divisão de frequência ortogonal clusterizado
(clustered orthogonal frequency division multiplexing - clustered-OFDM), aplicado à
sistema de comunicação via rede elétrica (power line communication - PLC). Nesse contexto,
introduz-se uma formulação para explicitar a influência do filtro digital no esquema clustered-
OFDM. A partir dessa formulação, uma equação que quantifica a vazão em função do uso dos
filtros digitais, a qual leva em consideração a relação sinal ruído multicanal, a especificação do
filtro e, principalmente, o comprimento dele, é apresentada. Através de simulações computacionais,
analisa-se o desempenho do esquema sujeito a um conjunto de filtros digitais previamente
selecionados, considerando três cenários: canal corrompido pelo ruído aditivo, gaussiano e
branco (additive white Gaussian noise - AWGN), canal PLC indoor corrompido ruído (medido
numa residência localizada na cidade de Juiz de Fora, MG) e canal PLC outdoor corrompido
pelo ruído (medido numa rede de distribuição de energia elétrica de baixa tensão na cidade de
Juiz de Fora, MG). De acordo com os resultados computacionais, dentre os filtros digitais analisados,
os filtros digitais Chebychev tipo II, FIR interpolado (interpolated FIR - IFIR) e FIR de
fase mínima e equiripple são, de maneira geral, os filtros digitais que proporcionam os melhores
benefícios (maior vazão e menor complexidade computacional). Considerando-se a influência
da precisão finita nesses três filtros digitais, conclui-se que o filtro digital IIR Chebychev tipo II
quantizado proporciona a menor perda de vazão e, portanto, é um filtro bastante adequado para
esquemas clustered-OFDM. / This work investigates the use of finite impulse response (FIR) and infinite impulse response
(IIR) digital filters to separate the signals belonging distinct clusters in a clustered orthogonal
frequency division multiplexing (clustered-OFDM) scheme, when it is applied to power line
communication (PLC) system. In this context, we introduce a formulation to take into account
the choice of the digital filter for the clustered-OFDM scheme. Based on this formulation, an
equation that quantifies the data-rate as a function ofmultichannel signal noise ratio, digital filter
design specification and length of the digital filter is presented. Performance analyses based on a
previously selected set of digital filters over three scenarios, channel corrupted by additivewhite
Gaussian noise (AWGN), indoor PLC channel corrupted by the noise (measured in a residence
located in Juiz de Fora city, MG) and outdoor PLC corrupted by the noise (measured in a low
voltage distribution network in Juiz de Fora city, MG), are presented. According to numerical
results, Chebychev type II, interpolated FIR (IFIR) and equiripple minimum phase FIR digital
filters offers the best benefits in terms of less data-rate loss and computer complexity reduction.
Considering the influence of the finite precision in these three digital filters, simulation results
shows that the quantized Chebychev type II IIR digital filter attains the smallest data-rate loss
and, as a consequence, it a very appropriate digital filter for clustered-OFDM schemes.
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4D evolution of fluvial system and channel-fill architecture of the Cretaceous Blackhawk Formation, Wasatch Plateau, Utah: An integrated fluvial rock record analysisSahoo, Hiranya 20 December 2013 (has links)
Using an integrated dataset comprising outcrop, core, GPR and LiDAR data, this study targets a high-quality outcrop "window" of the upper Cretaceous Blackhawk Formation in the eastern Wasatch Plateau in central Utah, spanning a fairly large spatial (~30 km2 area comprising eight contiguous, and vertical cliff faces) and temporal (~4 my) range. This research provides field-validation and -calibration of a wider range of fluvial heterogeneity: 1) large-scale heterogeneity (10’s of m vertically and 100’s of m laterally), 2) intermediate-scale heterogeneity (1’s of m vertically and 10’s of m laterally), and 3) small-scale heterogeneity (10’s of cm vertically and 1’s of m laterally). These sandbody- to facies-scale heterogeneities generate potential for stratigraphic compartmentalization for analogous fluvial reservoirs and prospects. Moreover, these results specifically constitute an outcrop analog to the producing tight-gas fluvial reservoirs of the adjacent hydrocarbon-prolific Uinta and Piceance Basins of Utah and Colorado, including the giant Jonah Field of Wyoming.
3D virtual outcrop model generated from LiDAR-integration has helped in avulsion-scale (~1's-10's kyr) to basin-fill scale (~100's kyr-1's myr) fluvial sandbody organization analysis down to channel-storey level. This high-resolution analysis has brought several intriguing insights. single-storey sandbodies are preferentially attendant to clustering organization, whereas multi-lateral sandbodies (i.e. channel-belt) show compensational-prone behavior. Sandbody organization is broadly compensational for the lower Blackhawk Formation, where the floodplain facies diversity is the highest. In contrast, floodplain diversity decreases stratigraphically upward such that the upper Blackhawk Formation shows the least heterogeneous floodplain with clustering-prone sandbody organization. In the quest of differentiating autogenic from allogenic signal in dynamic systems where their interplay is complexly intertwined, this study presents two incised-valley examples, where resultant fluvial organization has been interpreted, contrary to conventional wisdom, to be preferentially modulated by a dominant controlling mechanism of autogenic forcing. In filling these incised valley deposits, each of which is up to ~15-20 m thick, the dominating behavior of substrate coal compaction as an autogenic mechanism supplanted allogenic forcing (i.e. sea-level fluctuation).
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O agrupamento de cuidados no manejo do recém-nascido pré-termo: uma revisão sistemática / The clustered care for handling the preterm infants in the neonatal intensive care unit: a systematic reviewOliva, Cintia Luiza 21 March 2013 (has links)
Introdução: O agrupamento de cuidados é uma estratégia que visa evitar a manipulação intermitente dos neonatos pré-termos, proporcionando um período maior de repouso, fundamental para seu adequado crescimento e desenvolvimento. Esta prática é amplamente utilizada nas Unidades de Terapia Intensiva Neonatal (UTIN). Objetivo: Estabelecer evidências acerca da efetividade do agrupamento de cuidados na organização do ciclo sono-vigília, na estabilidade das respostas fisiológicas e mímica facial em pré-termos com idade gestacional até 32 semanas. Método: Revisão sistemática que identificou estudos publicados e indexados nas bases eletrônicas Cochrane, LILACS, EMBASE, CINAHL, PubMed, Web of Science. Foram utilizados os descritores/termos livres clustered care, neonatal individualized developmental care program OR NIDCAP, kangaroo mother care OR KMC e skin to skin para identificação dos estudos. Além destas bases, foram realizadas buscas por estudos não publicados em revistas indexadas como anais de eventos científicos, teses e dissertações indexadas nas bases eletrônicas de bancos de teses disponibilizados em páginas eletrônicas de universidades e pela ferramenta Google scholar. A análise e seleção das publicações foram realizadas por dois revisores independentes, as publicações com análises discrepantes para inclusão ou não na revisão foram submetidas à avaliação de um terceiro revisor. As publicações que atenderam os critérios de inclusão foram selecionadas para a leitura e análise na íntegra. Após esta avaliação, as que preencheram os critérios de inclusão, foram incluídas na revisão sistemática. Resultados: Foram identificadas 1255 publicações nas bases de dados, das quais 18 foram selecionadas como prováveis inclusão e analisadas na íntegra. Destas, cinco ensaios clínicos randomizados do tipo cross-over foram incluídos na presente revisão. Os sujeitos que compuseram a amostra dos ensaios clínicos analisados foram os neonatos pré-termos com idade gestacional igual ou inferior a 32 semanas. O agrupamento de cuidados foi comparado com um procedimento doloroso. Os resultados mostraram que os RNs apresentam alterações na mímica facial (olhos espremidos), alterações comporamentais (extenção de braços, língua protusa, mãos abertas com adução dos dedos, bocejo) e diminuição na saturação de oxigênio mais significativamente no grupo submetido ao procedimento doloroso comparado ao grupo de cuidados agrupados (p<0,004). No entanto, valores semelhantes nas alterações faciais e fisiológicas ocorreram no grupo submetido ao agrupamento de cuidados e os sinais de estresse avaliados após o agrupamento de cuidados, persisitiu por maior tempo, comparado com a fase de recuperação do neonato no grupo do procedimento doloroso. Quanto à frequência cardíaca, os neonatos com idade gestacional inferior a 30 semanas apresentaram elevados índices quando o procedimento doloroso foi precedido pelo agrupamento de cuidados (p<0,0001). Conclusões: As evidências encontradas sugerem que o agrupamento de cuidados causa alterações na resposta comportamental (ciclos sono-vigília), instabilidade nos parâmetros fisiológicos (frequência cardíaca e saturação de oxigênio) e sinais de estresse demonstrado através da mímica facial (sobrancelhas salientes e sulco nasolabial) em recém-nascidos com idade gestacional menor ou igual a 32 semanas. A adoção da prática de agrupamento de cuidados não garante que os neonatos pré-termos submetidos a este tipo de cuidado apresentem respostas fisiológicas e comportamentais mais estáveis. / Introduction: The clustered care is a strategy to avoid the intermittent preterm infants handling, providing them a longer rest period, essential to their health growth and development. This procedure is widely used in the context of Neonatal Intensive Care Units (NICU). Objective: To establish evidence concerning the effectiveness of the clustered care in organizing the sleep-wake cycle in the physiological responses and facial expressions in gestational age up to 32 weeks preterm infants. Methods: A systematic review that identified the studies published in the Cochrane, LILACS, EMBASE, CINAHL, PubMed and Web of Science electronic databases. The descriptors used to identify the studies were: \"clustered care, neonatal individualized developmental care program OR NIDCAP, kangaroo mother care OR KMC e skin to skin. Also these database, it was identified the studies not published in indexed journals including studies presented in scientific events and thesis and dissertations available in the electronic databases hosted in the universities homepages and publications identified by the Google scholar gate. The selection of publications and analysis of them were performed by two independent reviewers. The publications with conflicting evaluation between the two reviewers were submitted to evaluation by a third reviewer. The publications that met the inclusion criteria were selected for analysis of the full text. After this analysis, those studies that met the inclusion criteria were included in the systematic review. Results: We identified 1255 publications in databases, 18 of them were selected as probable inclusion and were analyzed in its entirety. From these 18 studies, five cross-over randomized clinical trials were included in this systematic review. The subjects who comprised the samples of analyzed trials were premature infants up to 32 week gestational age. The clustered care group was compared with a painful procedure. The results showed that newborns exhibited alterations in the facial expressions (eyes squeezed), behavior changes (arms extension, protruding tongue, open hands with fingers adduction, yawn) and oxygen saturation decreasing more significant in the group undergoing painful procedure compared with the clustered care group (p <0.004). However, similar values in facial and physiological changes occurred in the clustered care group and stress signals evaluated after grouping care, persisted for a longer time compared to the recovery phase in the newborn of painful procedure group. As for heart rate, neonates with gestational age below 30 weeks showed high levels when the painful procedure was preceded by clustered care (p <0.0001). Conclusions: The evidence suggests that the clustered care causes changes in the behavioral responses (sleep-wake cycles), instability in physiological parameters (heart rate and oxygen saturation) and stress signals demonstrated through facial expressions (protruding eyebrows and nasolabial folds) in the premature infants up to 32 weeks gestational age. he grouping of care does not guarantee that the preterm group undergoing care exhibit more stability in physiological and behavioral responses. The adoption of the clustered care practice does not guarantee that the preterm infant underwent to it exhibit more stability in the physiological and behavioral responses.
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Spaced Versus Massed Practice in L2 German Listening ComprehensionEmery, Rebecca Brinck 01 April 2017 (has links)
Students often have a difficult time understanding native speakers of their target language. This thesis examines two theories that may help students better understand NSs: spaced versus massed practice and the use of technology to enhance input. The study had the students of four sections of German 101 at BYU, divided into a spaced practice group that watched authentic German videos five minutes a day, six days a week for seven weeks and a massed practice group that watched authentic German videos for half an hour, one day a week for seven weeks, then gave them an immediate and a delayed listening comprehension posttest to see which improved more, along with several surveys to learn more about extraneous variables and the student experience with the activity. The results showed no significant difference between the two groups, but this is likely due to the many limitations of the study. The two biggest limitations were that of the 75 potential participants, only 13 allowed for their information to be used and had usable information, and that all of those 13 participants did too well on both posttests to be able to differentiate between them, so no conclusions were able to be drawn from this study.
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Using a Diffusive Approach for Load Balancing in Peer-to-peer SystemsQiao, Ying 01 May 2012 (has links)
We developed a diffusive load balancing scheme that equalizes the available capacities of nodes in a peer-to-peer (P2P) system. These nodes may have different resource capacities, geographic locations, or availabilities (i.e., length of time being part of the peer-to-peer system). The services on these nodes may have different service times and arrival rates of requests. Using the diffusive scheme, the system is able to maintain similar response times for its services. Our scheme is a modification of the diffusive load balancing algorithms proposed for parallel computing systems. This scheme is able to handle services with heterogeneous resource requirements and P2P nodes with heterogeneous capacities. We also adapted the diffusive scheme to clustered peer-to-peer system, where a load balancing operation may move services or nodes between clusters.
After a literature survey of this field, this thesis investigates the following issues using analytical reasoning and extensive simulation studies. The load balancing operations equalize the available capacities of the nodes in a neighborhood to their averages. As a result, the available capacities of all nodes in the P2P system converge to a global average. We found that this convergence is faster when the scheme uses neighborhoods defined by the structure of the structured P2P overlay network rather than using randomly selected neighbors. For a system with churn (i.e. nodes joining and leaving), the load balancing operations maintain the standard deviation of the available capacities of nodes within a bound. This bound depends on the amount of churn and the frequency of load balancing operations, as well as on the capacities of the nodes. However, the sizes of the services have little impact on this bound. In a clustered peer-to-peer system, the size of the bound largely depends on the average cluster size. When nodes are moved among clusters for load balancing, the numbers of cluster splits and merges are reduced. This may reduce the maintenance cost of the overlay network.
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Using a Diffusive Approach for Load Balancing in Peer-to-peer SystemsQiao, Ying 01 May 2012 (has links)
We developed a diffusive load balancing scheme that equalizes the available capacities of nodes in a peer-to-peer (P2P) system. These nodes may have different resource capacities, geographic locations, or availabilities (i.e., length of time being part of the peer-to-peer system). The services on these nodes may have different service times and arrival rates of requests. Using the diffusive scheme, the system is able to maintain similar response times for its services. Our scheme is a modification of the diffusive load balancing algorithms proposed for parallel computing systems. This scheme is able to handle services with heterogeneous resource requirements and P2P nodes with heterogeneous capacities. We also adapted the diffusive scheme to clustered peer-to-peer system, where a load balancing operation may move services or nodes between clusters.
After a literature survey of this field, this thesis investigates the following issues using analytical reasoning and extensive simulation studies. The load balancing operations equalize the available capacities of the nodes in a neighborhood to their averages. As a result, the available capacities of all nodes in the P2P system converge to a global average. We found that this convergence is faster when the scheme uses neighborhoods defined by the structure of the structured P2P overlay network rather than using randomly selected neighbors. For a system with churn (i.e. nodes joining and leaving), the load balancing operations maintain the standard deviation of the available capacities of nodes within a bound. This bound depends on the amount of churn and the frequency of load balancing operations, as well as on the capacities of the nodes. However, the sizes of the services have little impact on this bound. In a clustered peer-to-peer system, the size of the bound largely depends on the average cluster size. When nodes are moved among clusters for load balancing, the numbers of cluster splits and merges are reduced. This may reduce the maintenance cost of the overlay network.
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Detecção de agrupamento de microcalcificações em imagens de mamogramas digitalizados usando a transformada wavelet complexa de árvore duplaSá, Amandia de Oliveira 26 February 2016 (has links)
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Previous issue date: 2016-02-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Mammography is considered the “gold standard"in the early detection of breast cancer, being this disease one of the greatest health problems of women worldwide. Clustered microcalcifications detected on mammograms are very important findings in asymptomatic patients with early breast cancer and may be considered one of the first signs of malignancy. However, due to the small size of these structures, associated with the visual fatigue of radiologists resulting from the analysis of a large volume of images, clinical studies indicate that from 10 to 30% of microcalcifications presented in mammograms are lost during diagnosis. Within this scenario, this master thesis aims to develop an automatic system for the detection of clustered microcalcifications in digitized mammography images. To solve this problem, we use the transformed dua-three complex wavelet to detect the microcalsifications since this technique has some important characteristics for the signal analysis, for instance, good directional selectivity, approximate shift invariance and it provides both information - magnitude and phase. After the detection of isolated microcalcifications, a post-processing step is used to automatically demarcate regions containing clusters of microcalcifications. Furthermore, three techniques were investigated for the analysis of each clustered detection in order to identify false-positive clusters, such as: the Hessian matrix, the groups exclusion and the gray level co-occurrence matrix technique and SVM classifiers.
For the development and testing of the algorithms one digitized mammogram database were used. The analysis of the results were performed by using ROC and FROC curves. The method achieved good results when compared to the mark made by experts. / A mamografia é considerada o "padrão ouro"na detecção precoce do câncer de mama, sendo essa doença um dos maiores problemas de saúde da mulher no mundo. Agrupamentos de microcalcificações detectados nos mamogramas são achados muito importantes em pacientes assintomáticas com câncer de mama e podem representar o primeiro sinal de malignidade.
No entanto, devido ao reduzido tamanho dessas estruturas, associado à fadiga visual dos radiologistas resultante da análise de grandes volumes de imagens, estudos clínicos indicam que de 10 a 30% das microcalcificações presentes nos mamogramas são perdidas durante o diagnóstico. Diante deste quadro, este trabalho de mestrado tem por objetivo o
desenvolvimento de um sistema automático para a detecção de agrupamentos de microcalcificações em imagens de mamogramas digitalizados. Para isso, utilizou-se a transformada wavelet complexa de árvore dupla (DT-CWT) para a detecção das microcalcificações, visto que essa técnica possui características importantes para a análise de sinais como, por exemplo,
boa seletividade direcional, invariância aproximada ao deslocamento e fornece ambas informações – magnitude e fase. Após a detecção das microcalcificações isoladas, uma etapa de pós-processamento foi utilizada para demarcar automaticamente regiões contendo agrupamentos de microcalcificações. Além disso, três técnicas foram investigadas para a análise de cada agrupamento detectado, com o intuito de identificar agrupamentos falsopositivos, sendo elas: a matriz Hessiana, a exclusão de agrupamentos e a técnica de matriz de coocorrência de níveis de cinza e classificadores SVMs. Uma base de dados de mamogramas digitalizados foi utilizada para o desenvolvimento e testes dos algoritmos. A análise dos resultados foi realizada usando curvas ROC e FROC. O método obteve bons resultados quando comparado às marcações realizadas por especialistas e presentes na base de dados.
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O agrupamento de cuidados no manejo do recém-nascido pré-termo: uma revisão sistemática / The clustered care for handling the preterm infants in the neonatal intensive care unit: a systematic reviewCintia Luiza Oliva 21 March 2013 (has links)
Introdução: O agrupamento de cuidados é uma estratégia que visa evitar a manipulação intermitente dos neonatos pré-termos, proporcionando um período maior de repouso, fundamental para seu adequado crescimento e desenvolvimento. Esta prática é amplamente utilizada nas Unidades de Terapia Intensiva Neonatal (UTIN). Objetivo: Estabelecer evidências acerca da efetividade do agrupamento de cuidados na organização do ciclo sono-vigília, na estabilidade das respostas fisiológicas e mímica facial em pré-termos com idade gestacional até 32 semanas. Método: Revisão sistemática que identificou estudos publicados e indexados nas bases eletrônicas Cochrane, LILACS, EMBASE, CINAHL, PubMed, Web of Science. Foram utilizados os descritores/termos livres clustered care, neonatal individualized developmental care program OR NIDCAP, kangaroo mother care OR KMC e skin to skin para identificação dos estudos. Além destas bases, foram realizadas buscas por estudos não publicados em revistas indexadas como anais de eventos científicos, teses e dissertações indexadas nas bases eletrônicas de bancos de teses disponibilizados em páginas eletrônicas de universidades e pela ferramenta Google scholar. A análise e seleção das publicações foram realizadas por dois revisores independentes, as publicações com análises discrepantes para inclusão ou não na revisão foram submetidas à avaliação de um terceiro revisor. As publicações que atenderam os critérios de inclusão foram selecionadas para a leitura e análise na íntegra. Após esta avaliação, as que preencheram os critérios de inclusão, foram incluídas na revisão sistemática. Resultados: Foram identificadas 1255 publicações nas bases de dados, das quais 18 foram selecionadas como prováveis inclusão e analisadas na íntegra. Destas, cinco ensaios clínicos randomizados do tipo cross-over foram incluídos na presente revisão. Os sujeitos que compuseram a amostra dos ensaios clínicos analisados foram os neonatos pré-termos com idade gestacional igual ou inferior a 32 semanas. O agrupamento de cuidados foi comparado com um procedimento doloroso. Os resultados mostraram que os RNs apresentam alterações na mímica facial (olhos espremidos), alterações comporamentais (extenção de braços, língua protusa, mãos abertas com adução dos dedos, bocejo) e diminuição na saturação de oxigênio mais significativamente no grupo submetido ao procedimento doloroso comparado ao grupo de cuidados agrupados (p<0,004). No entanto, valores semelhantes nas alterações faciais e fisiológicas ocorreram no grupo submetido ao agrupamento de cuidados e os sinais de estresse avaliados após o agrupamento de cuidados, persisitiu por maior tempo, comparado com a fase de recuperação do neonato no grupo do procedimento doloroso. Quanto à frequência cardíaca, os neonatos com idade gestacional inferior a 30 semanas apresentaram elevados índices quando o procedimento doloroso foi precedido pelo agrupamento de cuidados (p<0,0001). Conclusões: As evidências encontradas sugerem que o agrupamento de cuidados causa alterações na resposta comportamental (ciclos sono-vigília), instabilidade nos parâmetros fisiológicos (frequência cardíaca e saturação de oxigênio) e sinais de estresse demonstrado através da mímica facial (sobrancelhas salientes e sulco nasolabial) em recém-nascidos com idade gestacional menor ou igual a 32 semanas. A adoção da prática de agrupamento de cuidados não garante que os neonatos pré-termos submetidos a este tipo de cuidado apresentem respostas fisiológicas e comportamentais mais estáveis. / Introduction: The clustered care is a strategy to avoid the intermittent preterm infants handling, providing them a longer rest period, essential to their health growth and development. This procedure is widely used in the context of Neonatal Intensive Care Units (NICU). Objective: To establish evidence concerning the effectiveness of the clustered care in organizing the sleep-wake cycle in the physiological responses and facial expressions in gestational age up to 32 weeks preterm infants. Methods: A systematic review that identified the studies published in the Cochrane, LILACS, EMBASE, CINAHL, PubMed and Web of Science electronic databases. The descriptors used to identify the studies were: \"clustered care, neonatal individualized developmental care program OR NIDCAP, kangaroo mother care OR KMC e skin to skin. Also these database, it was identified the studies not published in indexed journals including studies presented in scientific events and thesis and dissertations available in the electronic databases hosted in the universities homepages and publications identified by the Google scholar gate. The selection of publications and analysis of them were performed by two independent reviewers. The publications with conflicting evaluation between the two reviewers were submitted to evaluation by a third reviewer. The publications that met the inclusion criteria were selected for analysis of the full text. After this analysis, those studies that met the inclusion criteria were included in the systematic review. Results: We identified 1255 publications in databases, 18 of them were selected as probable inclusion and were analyzed in its entirety. From these 18 studies, five cross-over randomized clinical trials were included in this systematic review. The subjects who comprised the samples of analyzed trials were premature infants up to 32 week gestational age. The clustered care group was compared with a painful procedure. The results showed that newborns exhibited alterations in the facial expressions (eyes squeezed), behavior changes (arms extension, protruding tongue, open hands with fingers adduction, yawn) and oxygen saturation decreasing more significant in the group undergoing painful procedure compared with the clustered care group (p <0.004). However, similar values in facial and physiological changes occurred in the clustered care group and stress signals evaluated after grouping care, persisted for a longer time compared to the recovery phase in the newborn of painful procedure group. As for heart rate, neonates with gestational age below 30 weeks showed high levels when the painful procedure was preceded by clustered care (p <0.0001). Conclusions: The evidence suggests that the clustered care causes changes in the behavioral responses (sleep-wake cycles), instability in physiological parameters (heart rate and oxygen saturation) and stress signals demonstrated through facial expressions (protruding eyebrows and nasolabial folds) in the premature infants up to 32 weeks gestational age. he grouping of care does not guarantee that the preterm group undergoing care exhibit more stability in physiological and behavioral responses. The adoption of the clustered care practice does not guarantee that the preterm infant underwent to it exhibit more stability in the physiological and behavioral responses.
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Bayesian analysis of regression models for proportional data in the presence of zeros and ones = Análise bayesiana de modelos de regressão para dados de proporções na presença de zeros e uns / Análise bayesiana de modelos de regressão para dados de proporções na presença de zeros e unsGalvis Soto, Diana Milena, 1978- 26 August 2018 (has links)
Orientador: Víctor Hugo Lachos Dávila / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Matemática Estatística e Computação Científica / Made available in DSpace on 2018-08-26T02:34:17Z (GMT). No. of bitstreams: 1
GalvisSoto_DianaMilena_D.pdf: 1208980 bytes, checksum: edbc193912a2a800da4936526ed79fa3 (MD5)
Previous issue date: 2014 / Resumo: Dados no intervalo (0,1) geralmente representam proporções, taxas ou índices. Porém, é possível observar situações práticas onde as proporções sejam zero e/ou um, representando ausência ou presença total da característica de interesse. Nesses casos, os modelos que analisam o efeito de covariáveis, tais como a regressão beta, beta retangular e simplex não são convenientes. Com o intuito de abordar este tipo de situações, considera-se como alternativa aumentar os valores zero e/ou um ao suporte das distribuições previamente mencionadas. Nesta tese, são propostos modelos de regressão de efeitos mistos para dados de proporções aumentados de zeros e uns, os quais permitem analisar o efeito de covariáveis sobre a probabilidade de observar ausência ou presença total da característica de interesse, assim como avaliar modelos com respostas correlacionadas. A estimação dos parâmetros de interesse pode ser via máxima verossimilhança ou métodos Monte Carlo via Cadeias de Markov (MCMC). Nesta tese, será adotado o enfoque Bayesiano, o qual apresenta algumas vantagens em relação à inferência clássica, pois não depende da teoria assintótica e os códigos são de fácil implementação, através de softwares como openBUGS e winBUGS. Baseados na distribuição marginal, é possível calcular critérios de seleção de modelos e medidas Bayesianas de divergência q, utilizadas para detectar observações discrepantes / Abstract: Continuous data in the unit interval (0,1) represent, generally, proportions, rates or indices. However, zeros and/or ones values can be observed, representing absence or total presence of a carachteristic of interest. In that case, regression models that analyze the effect of covariates such as beta, beta rectangular or simplex are not appropiate. In order to deal with this type of situations, an alternative is to add the zero and/or one values to the support of these models. In this thesis and based on these models, we propose the mixed regression models for proportional data augmented by zero and one, which allow analyze the effect of covariates into the probabilities of observing absence or total presence of the interest characteristic, besides of being possivel to deal with correlated responses. Estimation of parameters can follow via maximum likelihood or through MCMC algorithms. We follow the Bayesian approach, which presents some advantages when it is compared with classical inference because it allows to estimate the parameters even in small size sample. In addition, in this approach, the implementation is straightforward and can be done using software as openBUGS or winBUGS. Based on the marginal likelihood it is possible to calculate selection model criteria as well as q-divergence measures used to detect outlier observations / Doutorado / Estatistica / Doutora em Estatística
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