15 resultados para Série temporal

em Universidade Federal do Rio Grande do Norte(UFRN)


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The characteristics profile of individuals who develop AIDS in Brazil has changed over time. Among these modifications, a worrying finding is the increased incidence of AIDS in the elderly across the country. But, however, is not yet clear whether the increase in AIDS cases is sufficient to produce a change in the trend of measures in recent years in the Brazilian states, and this increase has an effect from the socioeconomic and demographic indicators. In this sense, the objective of this study is to analyze the AIDS incidence rates among the elderly in Brazil and its effect on socioeconomic and demographic inequalities in the period 2000 to 2012. This is an ecological time-series study to meet behavior of the time series of the incidence rates of AIDS in the elderly from 2000 to 2012. the rates were calculated using the secondary data from Diseases Information System Notification and the Brazilian Institute of Geography and Statistics. Data were analyzed statistically to know the trends in incidence rates, by polynomial regression model and joinpoint log-linear regression model, but also the simple linear regression analysis to find the relationship of trends with variables socioeconomic and demographic. SPSS 20.0® and Joinpoint 4.1.1 programs were used. All tests were carried out considering a significance of 5%. After the analysis, in Brazil were reported 62,052 new cases of AIDS in the elderly from 2000 to 2012. During this period, a significant increase was found for males, both aged 50-59 years (APPC: 3.46 %, p <0.001), such as above 59 years (AAPC: 4.38%; p <0.001). For females, the increase was significant and has the largest increments in the time series, when compared to males in both age groups (AAPC: 4.62%, p <0.001 and AAPC: 6.53%; p <0.001) respectively. The largest increases are observed in women and in the states of North and Northeast. In the Southeast Region is observed stabilization of rates throughout the series. The reason of trends between the sexes had a significant reduction, but also an approach in both age groups of the study, reaching a ratio of 1.7 males for every female in the youngest age group. The trends were related to illiteracy rates, with increasing social inequality and the lowest human development in the Brazilian states. We conclude that in Brazil the incidence of AIDS in the elderly follows an increasing trend in individuals over 50 years. Noteworthy are the highest rates of study in women and in the states of North and Northeast. In this sense, the country needs to enhance policies towards older people with STD / AIDS, training health professionals and developing effective measures for the prevention and early diagnosis of infected people, especially in places with limited resources and high social inequality. In the long term, it is developing new studies to understand whether the measures taken were effective in reducing the trends identified in this study.

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The soil heat flux and soil thermal diffusivity are important components of the surface energy balance, especially in ar id and semi-arid regions. The obj ective of this work was to carry out to estimate the soil heat flux from th e soil temperature measured at a single depth, based on the half-order time derivative met hod proposed by Wang and Bras (1999), and to establish a method capable of es timating the thermal diffusivity of the soil, based on the half order derivative, from the temporal series of soil temperature at two depths. The results obtained in the estimates of soil heat flux were compared with the values of soil heat flux measured through flux plates, and the thermal di ffusivity estimated was compared with the measurements carried out in situ. The results obtained showed excellent concordance between the estimated and measured soil heat flux, with correlation (r), coeffici ent of determination (R 2 ) and standard error (W/m 2 ) of: r = 0.99093, R 2 = 0.98194 and error = 2.56 (W/m 2 ) for estimated period of 10 days; r = 0,99069, R 2 = 0,98147 and error = 2.59 (W/m 2 ) for estimated period of 30 days; and r = 0,98974, R 2 = 0,97958 and error = 2.77 (W/m 2 ) for estimated period of 120 days. The values of thermal di ffusivity estimated by the proposed method showed to be coherent and consis tent with in situ measured va lues, and with the values found in the literature usi ng conventional methods.

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Desenvolvido no Parque das Dunas, segunda reserva ambiental urbana do Brasil, ocupando uma área de 1.172,80 hectares, com característica de mata atlântica de dunas, situada numa faixa litorânea na região urbana do município de Natal (05° 46 S, 35º 12 W), o presente estudo, realizado durante os anos de 2004 a 2006, teve como objetivo identificar as espécies de culicídeos existentes no Parque das Dunas, capazes de transmitir arbovírus, tendo em vista que em 2004 houve uma epizootia de saguis (Callitrix jacchus), que causou grande mortandade, sem definição do agente etiológico. No ano de 2004, foram pesquisados sete pontos no interior da mata, com instalação de 20 armadilhas de ovitrampas e 20 de bambu para coleta dos imaturos. Para os adultos, durante quatro vezes por semana, foram usadas as armadilhas de Sannhon. Foram coletados 5.691 imaturos, sendo 839 Ae. aegypti, 3.184 Ae. albopictus e 1.668 Hg. leucocelaenus. A coleta dos adultos foi realizada de 2004 a 2006, etapa em que se recolheu 17.506 culicídeos adultos, sendo 17.244 Wy. bourrouli, 255 Ae. aegypti, 593 Ae. albopictus, 1.275 Hg. leucocelaenus, 294 Oc. scapularis, 05 Oc. taeniorynchus, 02 Oc. serratus e 3 Li. durhami. Para os imaturos houve correlação significativa entre Ae. aegypti e umidade relativa do ar p = 0, 049 e pluviometria p = 0,00, Ae. albopictus apresentou correlação significativa positiva com a pluviometria, enquanto Hg. leucocelaenus não apresentou nenhuma das variáveis climáticas. Para os adultos, a análise de série temporal aponta flutuação sazonal significativa para Ae. aegypti (p = 0,003); Ae. albopictus (p = 0,04); Oc. scapularis (p = 0,008 ) e Hg. leucocelaenus (p = 0,003). Uma correlação significativa negativa foi observada entre o número de Ae. albopictus coletado e a temperatura (Corr= - 0,50, p = 0,01); isto é, para cada 1°C a mais há diminuição de 7 espécimes. Este estudo teve a participação de uma equipe multidisciplinar: biólogos, entomologistas, para confirmação das espécies; técnicos de laboratório, para acompanhamento diário das larvas eclodidas das armadilhas de ovitrampas. Teve a importante colaboração de profissionais da Fundação Oswaldo Cruz FIOCRUZ/Rio de Janeiro, da Universidade de São Paulo USP para identificação do grupo Wyeomyia.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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In this work, the study of some complex systems is done with use of two distinct procedures. In the first part, we have studied the usage of Wavelet transform on analysis and characterization of (multi)fractal time series. We have test the reliability of Wavelet Transform Modulus Maxima method (WTMM) in respect to the multifractal formalism, trough the calculation of the singularity spectrum of time series whose fractality is well known a priori. Next, we have use the Wavelet Transform Modulus Maxima method to study the fractality of lungs crackles sounds, a biological time series. Since the crackles sounds are due to the opening of a pulmonary airway bronchi, bronchioles and alveoli which was initially closed, we can get information on the phenomenon of the airway opening cascade of the whole lung. Once this phenomenon is associated with the pulmonar tree architecture, which displays fractal geometry, the analysis and fractal characterization of this noise may provide us with important parameters for comparison between healthy lungs and those affected by disorders that affect the geometry of the tree lung, such as the obstructive and parenchymal degenerative diseases, which occurs, for example, in pulmonary emphysema. In the second part, we study a site percolation model for square lattices, where the percolating cluster grows governed by a control rule, corresponding to a method of automatic search. In this model of percolation, which have characteristics of self-organized criticality, the method does not use the automated search on Leaths algorithm. It uses the following control rule: pt+1 = pt + k(Rc − Rt), where p is the probability of percolation, k is a kinetic parameter where 0 < k < 1 and R is the fraction of percolating finite square lattices with side L, LxL. This rule provides a time series corresponding to the dynamical evolution of the system, in particular the likelihood of percolation p. We proceed an analysis of scaling of the signal obtained in this way. The model used here enables the study of the automatic search method used for site percolation in square lattices, evaluating the dynamics of their parameters when the system goes to the critical point. It shows that the scaling of , the time elapsed until the system reaches the critical point, and tcor, the time required for the system loses its correlations, are both inversely proportional to k, the kinetic parameter of the control rule. We verify yet that the system has two different time scales after: one in which the system shows noise of type 1 f , indicating to be strongly correlated. Another in which it shows white noise, indicating that the correlation is lost. For large intervals of time the dynamics of the system shows ergodicity

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A mortalidade infantil é tida como um indicador sensível para descrever as condições de vida e de saúde de uma população, sendo, portanto, interpretada como a estimativa do risco de um nascido vivo morrer antes de completar o primeiro ano de vida. Esse indicador é considerado elevado quando atinge patamares superiores a 50/1.000 nascidos vivos, médios quando se encontra entre 20 e 49/1.000 e mais baixos quando está até 20/1.000. No Brasil, a Mortalidade Infantil tem evidenciado variações ao longo dos anos, e nas duas últimas décadas esse indicador tem sofrido um acentuado decréscimo, provavelmente devido à melhoria no acesso aos serviços de saúde, ao saneamento básico, redução da taxa de fecundidade, melhoria das condições de vida e implementação de tecnologias na atenção à saúde. O objetivo principal do estudo foi avaliar a tendência na mortalidade infantil no município de Garanhuns no período de 2003 a 2012, segundo áreas cobertas e não cobertas pela estratégia saúde da família. Foi realizado um estudo de série temporal, e para isso foram coletados os dados referentes aos nascidos vivos e óbitos de menores de 01 (um) ano através do Sistema de Informações de Atenção Básica – SIAB, nas áreas cobertas e não cobertas pela estratégia, a fim de estabelecer relação de possível causalidade entre a intervenção e o indicador. Os resultados foram apresentados em gráficos, com a curva da Mortalidade Infantil no município de Garanhuns entre os anos de 2003 e 2012 segmentado através das áreas cobertas e não cobertas pela estratégia saúde da família ao longo do mesmo período. Após a análise dos resultados, observou-se uma tendência de queda no coeficiente de mortalidade infantil tanto nas áreas cobertas pela estratégia saúde da família quanto nas áreas cobertas pelo PACS, e que não foi possível estabelecer isoladamente uma maior redução da mortalidade infantil em áreas cobertas pela estratégia. No entanto, os resultados das ações desenvolvidas pela estratégia saúde da família são consistentes e plausíveis de causar impacto no declínio da mortalidade infantil, sobretudo as ações voltadas para a saúde da mulher e da criança

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Introduction: The circadian system has neural projections for the Autonomic Nervous System (ANS), directly interfering with sympathetic-vagal modulation of the cardiovascular system. Disturbances in the circadian system, such as phase changes in light-dark cycle (LD), has been related to the risk of development of cardiovascular diseases due to increased sympathetic tone and reduction o Heart Rate Variability (HRV - RR intervals). Purpose: Investigate the interaction between Circadian Timing System and cardiac autonomic control in rats. Materials and methods: We used 18 Wistar rats (♀, age = 139.9 ± 32.1 days, weight = 219.5 ± 16.2 g), divided into three distinct groups: Control (CG), phase delay of 6h (GDe) and phase advance of 6h (GAd). Three animals were excluded during data collection (CG/GDe/GAd - n=5). Telemeters were surgically implanted in each animal for continuous acquisition of electrocardiographic (ECG) signals (duration of 21 days in the CG and 28 days in GDe/ GAd). A LD cycle was established 12h: 12h, beginning of light at18:00h and dark at 06:00h. The animals remained in the same CG LD cycle throughout the experimental period, while, on the 14th day of registration, the GDe and GAd underwent a delay and an advance in 6h, respectively. Throughout the experimental period, the locomotor activity (LA), the mean heart rate (mHR) and variables related to iRR [mean RR (mRR), SDNN, RMSSD, LF, HF and LF/ HF ratio ] were recorded. All data were analyzed in blocks of 3 and 7 days, for the presence of circadian rhythm, values of Cosinor - mesor, amplitude and acrophase (paired t test), phase relationship, differences between light and dark (t test independent), averages every 30 minutes along each time series (two-way ANOVA with post hoc Bonferroni). The data block B1,M1 and M2 in CG served as benchmarks for comparisons between series of analysis of the GAT/GAV. Results: We observed circadian rhythmicity in the variables LA, mRR and mFC(p<0.01). mRR and mFC showed phase relationship with the LA in all three groups, being less stable in GAd. In the CG, no significant differences between blocks were found in any of the analyzes(p>0.05). Among the 7 day blocks, there was a significant reduction in mRR(p=0.04) and mFC(p=0.03) in GDe and significant reduction in HF mean(p=0.02) in GAd; and between 3 day blocks, a significant increase of LF/HF(p= 0.04) in the GDe; besides mRR(p=0.03), SDNN(p=0.04), RMSSD (p=0.04), LF (p=0.01) and HF(p=0.02) significant increase in the GAd. It was found that the differences between the means of the mRR, LA and mFC in light and dark phases were not significant after phase changes in some of the blocks/moments (GDe and GAd). No significant results were found when comparing rhythmic variables means every 30 minutes over the blocks, except for a significant decrease in mRR at the middle of the dark phase (B2) and the start of light phase (B3) - (p<0.01). Conclusion: phase advances and delays (6h) altered cardiac autonomic control in the experimental groups by temporarily HRV decrease. Phase advances apparently had greater negative interference in this process, in relation to the phase delays.

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This work proposes a modified control chart incorporating concepts of time series analysis. Specifically, we considerer Gaussian mixed transition distribution (GMTD) models. The GMTD models are a more general class than the autorregressive (AR) family, in the sense that the autocorrelated processes may present flat stretches, bursts or outliers. In this scenario traditional Shewhart charts are no longer appropriate tools to monitoring such processes. Therefore, Vasilopoulos and Stamboulis (1978) proposed a modified version of those charts, considering proper control limits based on autocorrelated processes. In order to evaluate the efficiency of the proposed technique a comparison with a traditional Shewhart chart (which ignores the autocorrelation structure of the process), a AR(1) Shewhart control chart and a GMTD Shewhart control chart was made. An analytical expression for the process variance, as well as control limits were developed for a particular GMTD model. The ARL was used as a criteria to measure the efficiency of control charts. The comparison was made based on a series generated according to a GMTD model. The results point to the direction that the modified Shewhart GMTD charts have a better performance than the AR(1) Shewhart and the traditional Shewhart.

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The objective of this research was to investigate monthly climatological, seasonal, annual and interdecadal of the reference evapotranspiration (ETo) in Acre state in order to better understand its spatial and temporal variability and identify possible trends in the region. The study was conducted with data from Rio Branco municipalities, the state capital, Tarauacá and Cruzeiro do Sul considering a 30-year period (1985-2014), from monthly data from weather stations surface of the National Institute of Meteorology. The methodology was held, first, the consistency of meteorological data. Thus, it was made the gap filling in the time series by means of multivariate techniques. Subsequently were performed statistical tests trend (Mann-Kendall) and homogeneity, by Sen's estimator of the magnitude of this trend is estimated, as well as computational algorithms containing parametric and non-parametric tests for two samples to identify from that year the trend has become significant. Finally, analysis of variance technique (ANOVA) was adopted in order to verify whether there were significant differences in average annual evapotranspiration between locations. The indirect method of Penman-Montheith parameterized by FAO was used to calculate the ETo. The results of this work through examination of the descriptive statistics showed that the ETo the annual average was 3.80, 2.92 and 2.86 mm day-1 year, to Rio Branco, Tarauacá and Cruzeiro do Sul, respectively. Featuring quite remarkable seasonal pattern with a minimum in June and a maximum in October, with Rio Branco to town one with the strongest signal (amplitudes) on the other hand, the Southern Cross presented the highest variability among the studied locations. By ANOVA it was found that the average annual statistically different for a significance level of 1% between locations, but the annual average between Cruzeiro do Sul and Tarauacá no statistically significant differences. For the three locations, the 2000s was the one with the highest ETo values associated with warmer waters of the North Atlantic basin and the 80s to lower values, associated with cooler waters of this basin. By analyzing the Mann-kendall and Sen estimator test, there was a trend of increasing the seasonal reference evapotranspiration (fall, winter and spring) on the order of 0.11 mm per decade and that from the years of 1990, 1996 and 2001 became statistically significant to the localities of Cruzeiro do Sul Tarauacá and Rio Branco, respectively. For trend analysis of meteorological parameters was observed positive trend in the 5% level of significance, for average temperature, minimum temperature and solar radiation.

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The time series analysis has played an increasingly important role in weather and climate studies. The success of these studies depends crucially on the knowledge of the quality of climate data such as, for instance, air temperature and rainfall data. For this reason, one of the main challenges for the researchers in this field is to obtain homogeneous series. A time series of climate data is considered homogeneous when the values of the observed data can change only due to climatic factors, i.e., without any interference from external non-climatic factors. Such non-climatic factors may produce undesirable effects in the time series, as unrealistic homogeneity breaks, trends and jumps. In the present work it was investigated climatic time series for the city of Natal, RN, namely air temperature and rainfall time series, for the period spanning from 1961 to 2012. The main purpose was to carry out an analysis in order to check the occurrence of homogeneity breaks or trends in the series under investigation. To this purpose, it was applied some basic statistical procedures, such as normality and independence tests. The occurrence of trends was investigated by linear regression analysis, as well as by the Spearman and Mann-Kendall tests. The homogeneity was investigated by the SNHT, as well as by the Easterling-Peterson and Mann-Whitney-Pettit tests. Analyzes with respect to normality showed divergence in their results. The von Neumann ratio test showed that in the case of the air temperature series the data are not independent and identically distributed (iid), whereas for the rainfall series the data are iid. According to the applied testings, both series display trends. The mean air temperature series displays an increasing trend, whereas the rainfall series shows an decreasing trend. Finally, the homogeneity tests revealed that all series under investigations present inhomogeneities, although they breaks depend on the applied test. In summary, the results showed that the chosen techniques may be applied in order to verify how well the studied time series are characterized. Therefore, these results should be used as a guide for further investigations about the statistical climatology of Natal or even of any other place.

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The variability / climate change has generated great concern worldwide, is one of the major issues as global warming, which can is affecting the availability of water resources in irrigated perimeters. In the semiarid region of Northeastern Brazil it is known that there is a predominance of drought, but it is not enough known about trends in climate series of joint water loss by evaporation and transpiration (evapotranspiration). Therefore, this study aimed to analyze whether there is increase and / or decrease evidence in the regime of reference evapotranspiration (ETo), for the monthly, annual and interdecadal scales in irrigated polo towns of Juazeiro, BA (9 ° 24'S, 40 ° 26'W and 375,5m) and Petrolina, PE (09 ° 09'S, 40 ° 22'W and 376m), which is the main analysis objective. The daily meteorological data were provided by EMBRAPA Semiárido for the period from 01.01.1976 to 31.12.2014, estimated the daily ETo using the standard method of Penman-Monteith (EToPM) parameterized by Smith (1991). Other methods of more simplified estimatives were calculated and compared to EToPM, as the ones following: Solar Radiation (EToRS), Linacre (EToL), Hargreaves and Samani (EToHS) and the method of Class A pan (EToTCA). The main statistical analysis were non-parametric tests of homogeneity (Run), trend (Mann-kendall), magnitude of the trend (Sen) and early trend detection (Mann-Whitney). The statistical significance adopted was 5 and / or 1%. The Analysis of Variance - ANOVA was used to detect if there is a significant difference in mean interdecadal mean. For comparison between the methods of ETo, it were used the correlation test (r), the Student t test and Tukey levels of 5% significance. Finally, statistics Willmott et al. (1985) statistics was used to evaluate the concordance index and performance of simplified methods compared to the standard method. It obtained as main results that there was a decrease in the time series of EToPM in irrigated areas of Juazeiro, BA and Petrolina, PE, significant respectively at 1 and 5%, with an annual magnitude of -14.5 mm (Juazeiro) and -7.7 mm (Petrolina) and early trend in 1996. The methods which had better for better agreement with EToPM were EToRS with very good performance, in both locations, followed by the method of EToL with good performance (Juazeiro) and median (Petrolina). EToHS had the worst performance (bad) for both locations. It is suggested that this decrease of EToPM can be associated with the increase in irrigated agricultural areas and the construction of Sobradinho lake upstream of the perimeters.

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Timeplace learning is the capacity of organisms to associate both space and time with a biological relevant stimulus such as food. Experiments are usually done with food restricted animals due to the belief that food system activation is necessary for timeplace learning. Another line of thought suggest that, in addition to food system activation, response cost should be increased to effectively allow timeplace discrimination. The purpose of this experiment was to test whether a complex environment, which presumably implied in a heightened response cost, would facilitate timeplace association in satiated rats using a highly palatable food as reward. Nine rats were trained in a timeplace task for 30 nonconsecutive days. A large experimental box (1x1m) divided in four compartments was used. To access each compartment the animal had to overcome a series of obstacles such as ramps, staircases and mazes. Two feeders localized in opposite compartments were rewarded with sunflower seeds in two daily sessions. One feeder offered the reward during the morning sessions while the second feeder in afternoon sessions. After the 15th day of training, the animals began to show a preference for the correct feeder during the correct time of day expressed by increased frequency of visits as well as lower latency to access the feeders. These results suggest that satiated animals are also capable of learning a timespace task as far as the experimental context is complex enough to result in a higher response cost