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Periodontal diseases are a global oral health problem affecting almost 10% of the global population. Porphyromonas gingivalis is one of the main bacteria involved in the initiation and progression of inflammatory processes as a result of the action of the cysteine proteases lysin- and arginine-gingipain. Surelease/polycarbophil microparticles containing a lyophilized proanthocyanidin-enriched fraction from the rhizomes of Limonium brasiliense, traditionally named “baicuru” (ethyl acetate fraction), were manufactured. The ethyl acetate fraction was characterized by UHPLC by the presence of samarangenins A and B (12.10 ± 0.07 and 21.05 ± 0.44%, respectively) and epigallocatechin-3-O-gallate (13.44 ± 0.27%). Physiochemical aspects of Surelease/polycarbophil microparticles were characterized concerning particle size, zeta potential, entrapment efficiency, ethyl acetate fraction release, and mucoadhesion. Additionally, the presence of the ethyl acetate fraction-loaded microparticles was performed concerning potential influence on viability of human buccal KB cells, P. gingivalis adhesion to KB cells, gingipain activity, and P. gingivalis biofilm formation. In general, all Surelease/polycarbophil microparticles tested showed strong adhesion to porcine cheek mucosa (93.1 ± 4.2% in a 30-min test), associated with a prolonged release of the ethyl acetate fraction (up to 16.5 ± 0.8% in 24 h). Preincubation of KB cells with Surelease/polycarbophil microparticles (25 µg/mL) resulted in an up to 93 ± 2% reduced infection rate by P. gingivalis. Decreased activity of the P. gingivalis-specific virulence factors lysin- and arginine-gingipain proteases by Surelease/polycarbophil microparticles was confirmed. Surelease/polycarbophil microparticles decreased biofilm formation of P. gingivalis (97 ± 2% at 60 µg/mL). Results from this study prove the promising activity of Surelease/polycarbophil microparticles containing ethyl acetate fraction microparticles as a prophylaxis strategy to prevent the recurrence of P. gingivalis.

The meliponines can be found in tropical and subtropical regions and is observed in the majority of Latin America. Scaptotrigona bipunctata are stingless bees that build colonies that possess between 2,000 and 50,000 individuals. This study aimed to estimate the toxicity of the insecticide acephate after oral and contact contamination in S. bipunctata. Results revealed differences between the two types of contamination and indicated that S. bipunctata is tolerant to acephate since the mortality rate was low. The findings indicated that there were expression changes of isoenzyme esterases after contamination with the insecticide, which was able to partially inhibit almost all of the enzymes identified in this study. In addition, morphological changes were identified in the midgut of the bees in the first 24 hours of contamination. However, after 48 hours it was observed the regeneration of the peritrophic membrane and other structures, contributing to the survival of the insects. It is essential to propose measures to minimize the impact of agrochemicals on pollinators and this study provides support for investigations on pesticide toxicity in stingless bees.

Generalized additive mixed models (GAMM) are useful when the nature of the data is longitudinal, which include the nonlinearity of the individual trajectories of the subjects, associating these with the assumption of the existence of random effects for each individual. In these models it is possible to rewrite the predictor as a sum of smooth nonparametric functions and then use the smooth technique P-spline. Thus, using the generalized additive mixed models with P-splines, this article aims to verify the impact of the types of mortars and the concentration levels of an additive content on the evolution of mortar weight contained in specimens over time, verifying possible differences between combinations of types and concentration. In relation to the results, it was observed through the analyzes that there were significant differences in the estimated curves of the weight evolution in both types of mortar, concluding that the matured mortar has a water absorption speed by capillarity higher than dry mortar. All the necessary assumptions for the validity of the model have been satisfied. Los modelos aditivos generalizados mixtos (GAMM) son útiles cuando la naturaleza de los datos es longitudinal, que incluyen la no linealidad de las trayectorias individuales de los sujetos, asociándolas a la suposición de la existencia de efectos aleatorios para cada individuo. En estos modelos es posible reescribir el predictor como una suma de funciones no paramétricas suaves y luego usar la técnica suave P-spline. Así, utilizando los modelos mixtos aditivos generalizados con P-splines, este artículo tiene como objetivo verificar el impacto de los tipos de morteros y los niveles de concentración de un contenido de aditivo en la evolución del peso del mortero contenido en las muestras a lo largo del tiempo, verificando posibles diferencias entre combinaciones. de tipos y concentración. En relación a los resultados, se observó a través de los análisis que existían diferencias significativas en las curvas estimadas de evolución del peso en ambos tipos de mortero, concluyendo que el mortero madurado tiene una velocidad de absorción de agua por capilaridad superior al mortero seco. Se han satisfecho todos los supuestos necesarios para la validez del modelo. Os modelos aditivos generalizados mistos (GAMM) são úteis quando a natureza dos dados é longitudinal, que inclui a não linearidade das trajetórias individuais dos sujeitos, associando-as à suposição da existência de efeitos aleatórios para cada indivíduo. Nesses modelos é possível reescrever o preditor como uma soma de funções não paramétricas suaves e então usar a técnica de suavização P-spline. Assim, utilizando os modelos mistos aditivos generalizados com P-splines, este artigo tem como objetivo verificar o impacto dos tipos de argamassas e dos níveis de concentração de um teor de aditivo na evolução do peso da argamassa contida nos corpos de prova ao longo do tempo, verificando possíveis diferenças entre combinações de tipos e concentração. Em relação aos resultados, observou-se através das análises que houve diferenças significativas nas curvas estimadas da evolução de massa nos dois tipos de argamassa, concluindo que a argamassa maturada possui uma velocidade de absorção de água por capilaridade superior à argamassa seca. Todas as suposições necessárias para a validade do modelo foram satisfeitas.

In the current work, the adsorption of bisphenol A (BPA) was investigated using a metal–organic framework (MIL-100). MIL-100 was prepared using a homemade microwave oven and characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) analysis, and physisorption analysis based on the Brunauer–Emmett–Teller BET surface area. Response surface methodology (RSM) was used to optimize the adsorption conditions, i.e., pH and the initial concentrations of BPA and the adsorbent; the BPA adsorption was considered the response. Using a central composite design (CCD), we obtained an experimental model validated by ANOVA and the interaction of two significant factors using RSM to the response. The laboratory experiments using MIL-100 revealed excellent adsorption activity toward BPA in water. The optimum conditions for BPA removal were 1.0 mg MIL-100 concentration and 200 mg/L initial BPA concentration. Under these conditions, the maximum adsorption of 1400 mg/g, which was higher than that previously reported, was obtained due to the favorable physicochemical properties of the adsorbent, such as large surface area, high porosity, and high stability. These results showed that MIL-100 can be an effective adsorbent for water decontamination by BPA removal; furthermore, statistical analysis can be used for adsorption tests, thereby reducing the number of experiments and making the analysis environmentally friendly.

This article presents an application of three classical models to studies of ruminal degradation kinetics, namely Ørskov and McDonald’s model (1979); Van Milgen, Murphy and Berger’s model (1991), and Richard’s model proposed in France, Dijkstra, and Dhanoa (1996). Our approach is focused on accounting for animal e ects given that measurements are repeated in the same animal. The models were studied under the perspective of nonlinear mixed-e ects (NLME) models. In this way, we intended to accommodate the problems of response variance heterogeneity and correlations between repeated measures. To apply the proposed method, we used data from an experiment conducted in a Latin square design to assess the dry matter degradability of the following three silages: Elephant grass (Pennisetum purpureum Schumach.) silage treated with bacterial inoculant, Elephant grass silage treated with enzyme-bacterial inoculant, and corn (Zea mays L.) silage. Samples were incubation for 0, 2, 6, 12 , 24, 48, 72 and 96 h. For these experimental data, the Van Milgen, Murphy, and Berger’s model showed better performance than the others. The proposed approach indicated that inclusion of animal e ects is important for obtaining more accurate information and can be considered in NLME modeling. Furthermore, it was also possible to perform an easy-to-interpret analysis of contrasts between treatments by using Tukey’s test.

Concerning the specificities of a longitudinal study, the trajectories of a subject's mean responses not always present a linear behavior, which calls for tools that take into account the non-linearity of individual trajectories and that describe them towards associating possible random effects with each individual. Generalized additive mixed models (GAMMs) have come to solve this problem, since, in this class of models, it is possible to assign specific random effects to individuals, in addition to rewriting the linear term by summing unknown smooth functions, not parametrically specified, then using the P-splines smoothing technique. Thus, this article aims to introduce this methodology applied to a dataset referring to an experiment involving 57 Swiss mice infected by Trypanosoma cruzi, which had their weights monitored for 12 weeks. The analyses showed significant differences in the weight trajectory of the individuals by treatment group; besides, the assumptions required to validate the model were met. Therefore, it is possible to conclude that this methodology is satisfactory in modeling data of longitudinal sort, because, with this approach, in addition to the possibility of including fixed and random effects, these models allow adding complex correlation structures to residuals.

Asiatic citrus canker (ACC, caused by the bacterium Xanthomonas citri subsp. citri) is a destructive disease of citrus in Brazil and in several other citrus-producing countries. ACC management is problematic, and bactericides such as copper can be reasonably efficacious but do not completely control the disease. Furthermore, injury by citrus leaf miner (CLM) can exacerbate severity of ACC. Host resistance is the most desirable solution for management of ACC; however, evaluations of germplasm indicate that resistance is limited in many popular species and cultivars that are grown commercially. Limited evaluations have been made of sweet orange (Citrus sinensis) selections. We evaluated resistance of 25 Pêra sweet orange selections to X. citri subsp. citri by wound inoculation and measuring lesion diameter under greenhouse conditions (wound inoculation indicates mesophyll resistance which will be valuable in areas where CLM exists). ACC severity was assessed on the same 25 selections at three locations in the field in Brazil, relying on natural inoculum and conditions to cause disease. In the greenhouse experiments, the selections EEL, Bianchi/CC, Ipiguá, Olimpia, IAC 2000/1, and Ovale Siracusa consistently had the smallest diameter lesions, indicating greatest resistance, although differences in lesion diameter were small. Results from the field experiments were less conclusive, although EEL and Ovale Siracusa were consistently numerically least affected by ACC. These results indicate selections of sweet orange that might be preferable to consider in canker-prone areas in Brazil and elsewhere.

Comparison between two distinct groups using a partial diallel and considering reciprocal effects has not been described in the scientific literature, limiting diallel analysis results. This study compared two groups of parents using a partial diallel, and analyzed the general and specific combining ability and reciprocal effects, divided into maternal and cytoplasmic. A partial diallel was established with nine maize hybrids, including the F1 and reciprocal hybrids for grain yield. For this application, the reciprocal effects were not significant. The proposed model would provide plant breeders with additional information to analyze partial diallel mating designs.

Citrus canker, caused by the bacterium Xanthomonas citri subsp. citri, is one of the most important diseases of citrus. The use of resistant genotypes plays an important role in the management and control of the disease and is the most environmentally sustainable approach to disease control. Citrus canker incidence was recorded in an experiment on nine genotypes of the sweet orange variety 'Pera' grafted on four rootstocks. The experiment was started in 2010 and the incidence of citrus canker on the leaves was recorded on a quarterly basis. The incidence data from the experiment were analyzed using a zero-inflated Beta regression model (RBIZ), which is the appropriate method to describe data with large numbers of zeros. Based on the residual analysis, the data fit the model well. The discrete component of the explanatory variable, rootstock, was not significant as a factor affecting the onset of disease, in contrast with the continuous component, genotype, which was significant in explaining the incidence of citrus canker. RESUMO. O cancro cítrico, causado pela bactéria Xanthomonas citri subsp. citri é uma das doenças mais importantes da citricultura. A utilização de genótipos resistentes à doença assume um papel importante no manejo e controle do patógeno, sendo essa uma medida viável ao produtor e sustentável ao ambiente. O conjunto de dados utilizado neste trabalho consistiu das observações obtidas de um experimento em que foram empregados como material vegetal, nove genótipos de Laranja doce, variedade Pera enxertado em quatro diferentes porta-enxertos. Este experimento teve inicio em 2010 e foram realizadas avaliações trimestrais para determinar a incidência de cancro nas folhas das plantas. Para a análise dos observações resultantes desse experimento foi utilizado a regressão Beta inflacionada de zero (RBIZ), que é a metodologia adequada para descrever proporções com grandes quantidades de zeros. A partir da análise residual, pode-se perceber que os dados se apresentaram de maneira homogênea indicando um bom ajuste do modelo. Para o componente discreto a variável explicativa, porta enxerto, foi significativa para o não aparecimento da doença, em contraste com o componente contínuo, em que a variável genótipo mostrou-se significativa para explicar a incidência de cancro cítrico.

Zero-inflated data from field experiments can be problematic, as these data require the use of specific statistical models during the analysis process. This study utilized the zero-inflated negative binomial (ZINB) model with the log- and logistic-link functions to describe the incidence of plants with Huanglongbing (HLB, caused by Candidatus liberibacter spp.) in commercial citrus orchards in the Northwestern Parana State, Brazil. Each orchard was evaluated at different times. The ZINB model with random effects in both link functions provided the best fit, as the inclusion of these effects accounted for variations between orchards and the numbers of diseased plants. The results of this model show that older plants exhibit a lower probability of acquiring HLB. The application of insecticides on a calendar basis or during new foliage flushes resulted in a three times larger probability of developing HLB compared with applying insecticides only when the vector was detected. RESUMO. Em diversas áreas do conhecimento, dados com excesso de zeros são encontrados com frequência. Para a análise de tais dados, é recomendado utilizar modelos que permitam uma contagem deste excesso de zero de forma adequada. Neste artigo, o modelo binomial negativo inflacionado de zero (ZINB) foi utilizado para descrever o número de plantas doentes, acometidas por Huanglongbing, em pomares comercias de laranjeiras na região noroeste do Estado do Paraná. Entretanto, deve-se levar em consideração que cada pomar foi avaliado ao longo do tempo, sendo assim, neste contexto, o modelo ZINB com efeito aleatório em ambas as funções de ligação, logarítmica e logística, apresentou melhor ajuste aos dados, pois a introdução destes efeitos consideraram as variações entre os pomares e a dependência entre número de plantas doentes. A partir deste modelo é possível perceber que as plantas mais velhas tendem a apresentar menor probabilidade de adquirir a doença. Todavia, a aplicação de inseticidas e o manejo por calendário apresentam três vezes mais chance de apresentar a doença do que o manejo somente pela presença do vetor.

Approximately 70% of the Brazilian production of guarana (Paullinia cupana) seeds is absorbed by the beverage industries. Guarana has several pharmacological properties: energy stimulant, antimicrobial, chemoprophylactic, antigenotoxic, antidepressive, anxiolytic, and anti-amnesic effects. Supercritical carbon dioxide extraction of bioactive compounds from guarana seeds was carried out and optimized by an orthogonal array design (OA9(3(4))). The factors/levels studied were: modifier(s) (ethanol and/or methanol), extraction time (20, 40, and 60min), temperature (40, 50, and 60°C), and pressure (100, 200, and 300bar). The statistical design was repeated with increasing proportions of modifiers. The percentage of modifier used was proportional to the amount of polar compounds extracted. The best conditions for the supercritical extraction, based on the content of polyphenols, epicatechin/catechin quantification, yield and operating cost, proved to be: 40% ethanol:methanol during 40min, under 40°C, and 100bar. The temperature had a significant effect on the total phenolic content.

Zeros excess data are often found in practice, adequate analysis considers models that appropriately support, also, null observations counting. In this research, the Normal Random Effects Zero Inflated Beta Regression Model was studied and applied to modeling a experimental data set to describe the behavior, over time, of bacterial leaf citrus canker expected incidence in orange orchards, under influence of original rootstock and genotype. The adjustment allowed to quantify chances that a null mean incidence observation will come from a certain plant, according to rootstock and genotype, and to estimate its expected value according to this combination. The agronomic experiment considered all combinations between distinct four rootstocks and nine genotypes. The longitudinal model found that both, proportion of uninfected plants and expected incidence among diseased plants, underwent time action statistically significant influence, however the rootstock and genotype effect influence significantly just the proportion of uninfected plants. Laranja Caipira rootstock proved to be the most resistant to leaf citrus canker, as was the most susceptible is Limão Cravo rootstock. The genotypes IpiguaIAC, Arapongas, EEL and N59 presented the biggest, and statistically equivalent, chances of presenting an uninfected plant. Dados com excesso de zeros são encontrados muitas vezes na prática, uma análise adequada considera a utilização de modelos que suportem apropriadamente, também, a contagem de observações nulas. Nesta pesquisa, o Modelo de Regressão Beta Inflacionado de Zeros com Efeitos Aleatórios Normais foi estudado e aplicado à modelagem de um conjunto de dados experimentais a fim de descrever o comportamento, ao longo do tempo, da incidência esperada de cancro cítrico foliar bacteriano em pomares de laranja sob a influência do genótipo e do porta-enxerto de origem. O ajuste permitiu quantificar as chances de que uma observação nula para a incidência média seja proveniente de uma determinada planta, de acordo com o genótipo e o porta-enxerto, além de estimar o seu valor esperado conforme essa combinação. O experimento agronômico considerou todas as combinações entre quatro porta-enxertos e nove genótipos distintos. O modelo longitudinal constatou que tanto a proporção de plantas não infectadas, quanto a incidência esperada entre plantas doentes sofrem influência estatisticamente significativa da ação do tempo, contudo o efeito causado pelo porta-enxerto e genótipo influenciam significativamente somente a proporção de plantas não infectadas. O porta-enxerto Laranja Caipira mostrou ser o mais resistente ao cancro cítrico foliar, assim como o Limão Cravo mostrou ser o mais suscetível. Os genótipos IpiguaIAC, Arapongas, EEL e N59 apresentaram as maiores, e estatisticamente equivalentes, chances de apresentar uma planta não infectada. 127 f

This study had as objective to evaluate the genetic diversity of bees (Tetragonisca angustula and Tetragonisca weyrauchi) by means of microsatellite marker and PCR-RFLP, as well as the architectural features of the nests, the nidification place and the development of the colonies. In order to evaluate the genetic diversity some worker bees were collected from nests in Cacoal, Ji-Paraná, Jaru, Ariquemes, Cacaulândia, Monte Negro, Alto Paraíso and Porto Velho - Rondônia state. After isolating DNA, tests were performed with nine microsatellite primers. The success in the amplification and in the presence of Polymorphism occurred with four primers: (T3-32, Mbi33, Mbi254 and Tang 77) two species were selected for analysis because they demonstrate quality in the amplification of the loci. For PCR-RFLP marker, tests were carried out with ten pairs of heterologous primers that amplified different regions of the mitochondrial DNA, though, four primers (primer 1 - ND2 and COI; primer 2 - COI; primer 8 - 16S and 12S and primer 9 - COII) were used in this study. For restriction analysis of the amplified regions 13 enzymes were tested: EcoRI, EcoRV, HindIII, HinfI, RsaI, PstI, XbaI, HaeIII, ClaI, XhoI, BglII, PvuII and ScaI. In order to evaluate the development, different thicknesses and dimensions were used in Fernando Oliveira/INPA model hives, which were set in the town of Alto Paraíso - Rondônia state. From the analysis of the four primers of the microsatellite marker results, the highest heterozygosity values observed were estimated to site Tang77 of T. angustula (0,1333). The heterozygosity values expected greater than those heterozygosity observed and the positive values of FIS indicated that there is excess of homozygotes. The populations analyzed are moderately differentiated according to the estimated value of FST. The analysis of molecular variance indicated that 9% of the variation occurred among populations and 91% within populations. Analysis by Bayesian inference using Monte Carlo method by Markov chains (MCMC) did not separate the two kinds of Tetragonisca analyzed. The results using marker PCR-RFLP allowed to identify the primer 1 - (ND2, IOC) a fragment of approximately 2400 bp in T. angustula and T. weyrauchi. With the analysis of restriction endonuclease the fragment cleavage with EcoRI and EcoRV enzyme was verified. For region (IOC) primer 2 the two species amplified a fragment corresponding to about 1850 bp. Cleavage was verified with the EcoRV enzyme only in T. angustula individuals. However the cleavage with enzyme HinfI was observed in both species. The amplification of the primer 8 region (16S, 12S) generated two fragments (1850 bp and 350 bp), and the cleavage was observed in both species with the enzymes EcoRV, RsaI, PstI. Whereas enzyme XbaI cleaved in T. weyrauchi only. The amplification of the primer 9 region (IOC) showed a fragment of 1000 bp. The cleavage occurred with the enzyme ClaI and HinfI to T. angustula. The genetic identity value observed among populations was (0.3636) and the genetic distance was equal to 1.0116. The analysis by Bayesian inference estimated the real number of populations, K = 5. The architectural features of the nests discs with 6-11 cm were observed in T. angustula, in T. weyrauchi the average for the size of the disks was 11 cm. The nidification in T. angustula was recorded in tree and on the ground, while in T. weyrauchi they were found in fork trees. The nest with the smallest recorded weight was 50 g (T. angustula), whereas the highest was 250 g (T. weyrauchi). In T. weyrauchi nests, an observation not listed on the bionomics of the species was made, at the bottom of the nests a dumpster was found, where a large number of dead bees were deposited. A large number of colony loss was recorded during the experiment. The statistical analyzes conducted with GLM to T. angustula and T. weyrauchi indicated that there are significant differences between the hives. From the results found, it is concluded that the populations of evaluated bees the microsatellite markers used were not efficient in separating the two species. The variation detected with DNA analysis by PCR-RFLP of the two species of jataí showed that there are differences in mtDNA between the two species. These populations are well separated allowing us to observe that they have distinct pattern of mtDNA markers. And that the nest architecture differs not only in spiracles but also in dump that was recorded for T. weyrauchi. As for nidification, the frequency observed is higher for T. angustula when compared with T. weyrauchi. Hive model Fernando Oliveira / INPA are efficient for production for T. angustula, but are not suitable for T. weyrauchi. Este trabalho teve por objetivo avaliar a diversidade genética em abelhas (Tetragonisca angustula e Tetragonisca weyrauchi) utilizando marcador microssatélite e PCR-RFLP, assim como as características da arquitetura dos ninhos, local de nidificação e o desenvolvimento de colônias. Para avaliar a diversidade genética foram coletadas abelhas operárias de ninhos localizados em Cacoal, Ji-Paraná, Jaru, Ariquemes, Cacaulândia, Monte Negro, Alto Paraíso e Porto Velho - Rondônia. Após isolar o DNA foram realizados testes com nove primers microssatélites. O sucesso na amplificação e presença de polimorfismo ocorreu com quatro primers: (T3-32, Mbi33, Mbi254 e Tang 77) foram selecionados para análise das duas espécies, pois demonstraram qualidade na amplificação dos locos. Para o marcador PCR-RFLP, foram realizados testes com dez pares de primers heterólogos que amplificam diferentes regiões do DNA mitocondrial, porém quatro (primer 1 - ND2 e COI; primer 2 - COI; primer 8 - 16S e 12S e primer 9 - COII) foram utilizados no estudo. Para a análise de restrição das regiões amplificadas foram testadas 13 enzimas: EcoRI, EcoRV, HindIII, HinfI, RsaI, PstI, XbaI, HaeIII, ClaI, XhoI, BglII, PvuII e ScaI. Para avaliar o desenvolvimento foram utilizadas diferentes espessuras e dimensões em colmeias modelo Fernando Oliveira/INPA, instaladas no município de Alto Paraíso - Rondônia. A partir das análises dos resultados com os quatro primers do marcador microssatélite, os maiores valores de heterozigosidade observados foram estimados para o loco Tang77 de T. angustula (0,1333). Os valores de heterozigosidade esperados foram maiores que os de heterozigosidade observada e os valores positivos de FIS indicaram que há excesso de homozigotos. As populações analisadas são moderadamente diferenciadas de acordo com o valor estimado de FST. A análise de variância molecular indicou que 9% da variação ocorreram entre as populações e 91% dentro das populações. A análise por inferência bayesiana, utilizando o Método de Monte Carlo via cadeias de Markov (MCMC), não separaram as duas espécies de Tetragonisca analisadas. Os resultados que utilizaram marcador PCR-RFLP permitiram identificar para o primer 1 - (ND2, COI) um fragmento com aproximadamente 2400 pb em T. angustula e em T. weyrauchi. Com a análise das endonucleases de restrição foi verificada a clivagem do fragmento com a enzima EcoRI e EcoRV. Para região (COI) primer 2, as duas espécies amplificaram um fragmento que corresponde a aproximadamente 1850 pb. A clivagem foi verificada com a enzima EcoRV somente em indivíduos de T. angustula. Porém, a clivagem com a enzima HinfI foi observada nas duas espécies. A amplificação da região (16S, 12S) primer 8 gerou dois fragmentos (1850 pb e 350 pb), e foi observada a clivagem nas duas espécies com as enzimas EcoRV, RsaI, PstI. Enquanto que a enzima XbaI só clivou em T. weyrauchi. A amplificação da região (COII) primer 9 apresentou um fragmento com 1000 pb. A clivagem ocorreu com a enzima ClaI e HinfI para T. angustula. O valor de identidade genética observado entre as populações foi de (0,3636) e distância genética igual a 1,0116. A análise por inferência bayesiana estimou o número real de populações, K= 5. Já nas características da arquitetura dos ninhos em T. angustula foram observados discos com 6 a 11 cm, em T. weyrauchi a média para o tamanho dos discos foi de 11 cm. A nidificação em T. angustula foi registrada em árvore e solo, enquanto que em T. weyrauchi foram encontrados em forquilha de árvores. O ninho com o menor peso registrado foi de 50 g (T. angustula), enquanto que o maior foi de 250 g (T. weyrauchi). Em ninhos de T. weyrauchi foi realizada uma observação não registrada na bionomia da espécie. Na parte inferior dos ninhos foi encontrada uma lixeira, onde estava depositado um grande número de abelhas mortas. Foi registrado um grande número de perda de colônias durante o experimento. As análises estatísticas realizadas com GLM para T. angustula e T. weyrauchi indicaram que existem diferenças significativas entre as colmeias. A partir dos resultados encontrados conclui-se que nas populações de abelhas avaliadas os marcadores microssatélites utilizados não foram eficientes em separar as duas espécies estudadas. A variação detectada com as análises de mtDNA por PCR-RFLP das duas espécies de jataí mostrou que há diferenças no mtDNA entre as duas espécies. Essas populações estão bem diferenciadas, e permite observar que as populações tiveram padrão distintos de marcadores de mtDNA, e que a arquitetura do ninho difere não só nos respiráculos, mas também na lixeira que foi registrada para T. weyrauchi. Quanto à nidificação, a frequência observada é maior em T. angustula quando comparada a T. weyrauchi. As colmeias, modelo Fernando Oliveira/INPA, são eficientes para produção em T. angustula, mas não são adequadas para T. weyrauchi. xvii, 68, [1] f

Muitos equipamentos utilizados para quantificar substâncias, como toxinas em alimentos, freqüentemente apresentam deficiências para quantificar quantidades baixas. Em tais casos, geralmente indicam a ausência da substância quando esta existe, mas está abaixo de um valor pequeno \'ksi\' predeterminado, produzindo valores iguais a zero não necessariamente verdadeiros. Em outros casos, detectam a presença da substância, mas são incapazes de quantificá-la quando a quantidade da substância está entre \'ksai\' e um valor limiar \'tau\', conhecidos. Por outro lado, quantidades acima desse valor limiar são quantificadas de forma contínua, dando origem a uma variável aleatória contínua X cujo domínio pode ser escrito como a união dos intervalos, [ómicron, \"ksai\'), [\"ksai\', \'tau\' ] e (\'tau\', ?), sendo comum o excesso de valores iguais a zero. Neste trabalho, são propostos modelos que possibilitam discriminar a probabilidade de zeros verdadeiros, como o modelo de mistura com dois componentes, sendo um degenerado em zero e outro com distribuição contínua, sendo aqui consideradas as distribuições: exponencial, de Weibull e gama. Em seguida, para cada modelo, foram observadas suas características, propostos procedimentos para estimação de seus parâmetros e avaliados seus potenciais de ajuste por meio de métodos de simulação. Finalmente, a metodologia desenvolvida foi ilustrada por meio da modelagem de medidas de contaminação com aflatoxina B1, observadas em grãos de milho, de três subamostras de um lote de milho, analisados no Laboratório de Micotoxinas do Departamento de Agroindústria, Alimentos e Nutrição da ESALQ/USP. Como conclusões, na maioria dos casos, as simulações indicaram eficiência dos métodos propostos para as estimações dos parâmetros dos modelos, principalmente para a estimativa do parâmetro \'delta\' e do valor esperado, \'Epsilon\' (Y). A modelagem das medidas de aflatoxina, por sua vez, mostrou que os modelos propostos são adequados aos dados reais, sendo que o modelo de mistura com distribuição de Weibull, entretanto, ajustou-se melhor aos dados. Much equipment used to quantify substances, such as toxins in foods, is unable to measure low amounts. In cases where the substance exists, but in an amount below a small fixed value \'ksi\' , the equipment usually indicates that the substance is not present, producing values equal to zero. In cases where the quantity is between \'\'ksi\' and a known threshold value \'tau\', it detects the presence of the substance but is unable to measure the amount. When the substance exists in amounts above the threshold value ?, it is measure continuously, giving rise to a continuous random variable X whose domain can be written as the union of intervals, [ómicron, \"ksai\'), [\"ksai\', \'tau\' ] and (\'tau\', ?), This random variable commonly has an excess of zero values. In this work we propose models that can detect the probability of true zero, such as the mixture model with two components, one being degenerate at zero and the other with continuous distribution, where we considered the distributions: exponential, Weibull and gamma. Then, for each model, its characteristics were observed, procedures for estimating its parameters were proposed and its potential for adjustment by simulation methods was evaluated. Finally, the methodology was illustrated by modeling measures of contamination with aflatoxin B1, detected in grains of corn from three sub-samples of a batch of corn analyzed at the laboratory of of Mycotoxins, Department of Agribusiness, Food and Nutrition ESALQ/USP. In conclusion, in the majority of cases the simulations indicated that the proposed methods are efficient in estimating the parameters of the models, in particular for estimating the parameter ? and the expected value, E(Y). The modeling of measures of aflatoxin, in turn, showed that the proposed models are appropriate for the actual data, however the mixture model with a Weibull distribution fits the data best.

Em ensaios clínicos é muito comum a ocorrência de dados longitudinais discretos. Para sua análise é necessário levar em consideração que dados observados na mesma unidade experimental ao longo do tempo possam ser correlacionados. Além dessa correlação inerente aos dados é comum ocorrer o fenômeno de superdispersão (ou sobredispersão), em que, existe uma variabilidade nos dados além daquela captada pelo modelo. Um caso que pode acarretar a superdispersão é o excesso de zeros, podendo também a superdispersão ocorrer em valores não nulos, ou ainda, em ambos os casos. Molenberghs, Verbeke e Demétrio (2007) propuseram uma classe de modelos para acomodar simultaneamente a superdispersão e a correlação em dados de contagens: modelo Poisson, modelo Poisson-gama, modelo Poisson-normal e modelo Poisson-normal-gama (ou modelo combinado). Rizzato (2011) apresentou a abordagem bayesiana para o ajuste desses modelos por meio do Método de Monte Carlo com Cadeias de Markov (MCMC). Este trabalho, para modelar a incerteza relativa aos parâmetros desses modelos, considerou a abordagem bayesiana por meio de um método determinístico para a solução de integrais, INLA (do inglês, Integrated Nested Laplace Approximations). Além dessa classe de modelos, como objetivo, foram propostos outros quatros modelos que também consideram a correlação entre medidas longitudinais e a ocorrência de superdispersão, além da ocorrência de zeros estruturais e não estruturais (amostrais): modelo Poisson inacionado de zeros (ZIP), modelo binomial negativo inacionado de zeros (ZINB), modelo Poisson inacionado de zeros - normal (ZIP-normal) e modelo binomial negativo inacionado de zeros - normal (ZINB-normal). Para ilustrar a metodologia desenvolvida, um conjunto de dados reais referentes à contagens de ataques epilépticos sofridos por pacientes portadores de epilepsia submetidos a dois tratamentos (um placebo e uma nova droga) ao longo de 27 semanas foi considerado. A seleção de modelos foi realizada utilizando-se medidas preditivas baseadas em validação cruzada. Sob essas medidas, o modelo selecionado foi o modelo ZIP-normal, sob o modelo corrente na literatura, modelo combinado. As rotinas computacionais foram implementadas no programa R e são parte deste trabalho. Discrete and longitudinal structures naturally arise in clinical trial data. Such data are usually correlated, particularly when the observations are made within the same experimental unit over time and, thus, statistical analyses must take this situation into account. Besides this typical correlation, overdispersion is another common phenomenon in discrete data, defined as a greater observed variability than that nominated by the statistical model. The causes of overdispersion are usually related to an excess of observed zeros (zero-ination), or an excess of observed positive specific values or even both. Molenberghs, Verbeke e Demétrio (2007) have developed a class of models that encompasses both overdispersion and correlation in count data: Poisson, Poisson-gama, Poisson-normal, Poissonnormal- gama (combined model) models. A Bayesian approach was presented by Rizzato (2011) to fit these models using the Markov Chain Monte Carlo method (MCMC). In this work, a Bayesian framework was adopted as well and, in order to consider the uncertainty related to the model parameters, the Integrated Nested Laplace Approximations (INLA) method was used. Along with the models considered in Rizzato (2011), another four new models were proposed including longitudinal correlation, overdispersion and zero-ination by structural and random zeros, namely: zero-inated Poisson (ZIP), zero-inated negative binomial (ZINB), zero-inated Poisson-normal (ZIP-normal) and the zero-inated negative binomial-normal (ZINB-normal) models. In order to illustrate the developed methodology, the models were fit to a real dataset, in which the response variable was taken to be the number of epileptic events per week in each individual. These individuals were split into two groups, one taking placebo and the other taking an experimental drug, and they observed up to 27 weeks. The model selection criteria were given by different predictive measures based on cross validation. In this setting, the ZIP-normal model was selected instead the usual model in the literature (combined model). The computational routines were implemented in R language and constitute a part of this work.