Spatial distribution of Echinolitorina peruviana (Lamarck, 1882) for intertidal rocky shore in Antofagasta (23° S, Chile)

Abstract The intertidal rocky shores in continental Chile have high species diversity mainly in northern Chile (18-27° S), and one of the most widespread species is the gastropod Echinolittorina peruviana (Lamarck, 1822). The aim of the present study is do a first characterization of spatial distribution of E. peruviana in along rocky shore in Antofagasta town in northern Chile. Individuals were counted in nine different sites that also were determined their spectral properties using remote sensing techniques (LANDSAT ETM+). The results revealed that sites without marked human intervention have more abundant in comparison to sites located in the town, also in all studied sites was found an aggregated pattern, and in six of these sites were found a negative binomial distribution. The low density related to sites with human intervention is supported when spectral properties for sites were included. These results would agree with other similar results for rocky shore in northern and southern Chile.

Resumo As costas rochosas entremarés no Chile continental apresentam alta diversidade de espécies, principalmente no norte do país (18-27 ° S), e uma das espécies mais difundidas é o gastrópode Echinolittorina peruviana (Lamarck, 1822). O objetivo do presente estudo é fazer uma primeira caracterização da distribuição espacial de E. peruviana no costão rochoso da cidade de Antofagasta no norte do Chile. Os indivíduos foram contados em nove locais diferentes onde também foram determinadas suas propriedades espectrais usando técnicas de sensoriamento remoto (LANDSAT ETM +). Os resultados revelaram que os locais sem intervenção humana marcada apresentam maior abundância em comparação aos locais localizados no município. Também em todos os locais estudados foi encontrado um padrão agregado, sendo que em seis desses locais foi encontrada uma distribuição binomial negativa. A baixa densidade relacionada a sites com intervenção humana é suportada quando as propriedades espectrais para sites foram incluídas. Esses resultados concordariam com outros resultados semelhantes para costões rochosos no norte e no sul do Chile.

Spatial distribution of Echinolitorina peruviana (Lamarck, 1882) for intertidal rocky shore in Antofagasta (23° S, Chile) / Distribuição espacial de Echinolitorina peruviana (Lamarck, 1882) para costa rochosa entremarés em Antofagasta (23 ° S, Chile)

Abstract The intertidal rocky shores in continental Chile have high species diversity mainly in northern Chile (18-27° S), and one of the most widespread species is the gastropod Echinolittorina peruviana (Lamarck, 1822). The aim of the present study is do a first characterization of spatial distribution of E. peruviana in along rocky shore in Antofagasta town in northern Chile. Individuals were counted in nine different sites that also were determined their spectral properties using remote sensing techniques (LANDSAT ETM+). The results revealed that sites without marked human intervention have more abundant in comparison to sites located in the town, also in all studied sites was found an aggregated pattern, and in six of these sites were found a negative binomial distribution. The low density related to sites with human intervention is supported when spectral properties for sites were included. These results would agree with other similar results for rocky shore in northern and southern Chile.

Resumo As costas rochosas entremarés no Chile continental apresentam alta diversidade de espécies, principalmente no norte do país (18-27 ° S), e uma das espécies mais difundidas é o gastrópode Echinolittorina peruviana (Lamarck, 1822). O objetivo do presente estudo é fazer uma primeira caracterização da distribuição espacial de E. peruviana no costão rochoso da cidade de Antofagasta no norte do Chile. Os indivíduos foram contados em nove locais diferentes onde também foram determinadas suas propriedades espectrais usando técnicas de sensoriamento remoto (LANDSAT ETM +). Os resultados revelaram que os locais sem intervenção humana marcada apresentam maior abundância em comparação aos locais localizados no município. Também em todos os locais estudados foi encontrado um padrão agregado, sendo que em seis desses locais foi encontrada uma distribuição binomial negativa. A baixa densidade relacionada a sites com intervenção humana é suportada quando as propriedades espectrais para sites foram incluídas. Esses resultados concordariam com outros resultados semelhantes para costões rochosos no norte e no sul do Chile.

Spatial distribution of Echinolitorina peruviana (Lamarck, 1882) for intertidal rocky shore in Antofagasta (23° S, Chile) / Distribuição espacial de Echinolitorina peruviana (Lamarck, 1882) para costa rochosa entremarés em Antofagasta (23 ° S, Chile)

The intertidal rocky shores in continental Chile have high species diversity mainly in northern Chile (18-27° S), and one of the most widespread species is the gastropod Echinolittorina peruviana (Lamarck, 1822). The aim of the present study is do a first characterization of spatial distribution of E. peruviana in along rocky shore in Antofagasta town in northern Chile. Individuals were counted in nine different sites that also were determined their spectral properties using remote sensing techniques (LANDSAT ETM+). The results revealed that sites without marked human intervention have more abundant in comparison to sites located in the town, also in all studied sites was found an aggregated pattern, and in six of these sites were found a negative binomial distribution. The low density related to sites with human intervention is supported when spectral properties for sites were included. These results would agree with other similar results for rocky shore in northern and southern Chile.

As costas rochosas entremarés no Chile continental apresentam alta diversidade de espécies, principalmente no norte do país (18-27 ° S), e uma das espécies mais difundidas é o gastrópode Echinolittorina peruviana (Lamarck, 1822). O objetivo do presente estudo é fazer uma primeira caracterização da distribuição espacial de E. peruviana no costão rochoso da cidade de Antofagasta no norte do Chile. Os indivíduos foram contados em nove locais diferentes onde também foram determinadas suas propriedades espectrais usando técnicas de sensoriamento remoto (LANDSAT ETM +). Os resultados revelaram que os locais sem intervenção humana marcada apresentam maior abundância em comparação aos locais localizados no município. Também em todos os locais estudados foi encontrado um padrão agregado, sendo que em seis desses locais foi encontrada uma distribuição binomial negativa. A baixa densidade relacionada a sites com intervenção humana é suportada quando as propriedades espectrais para sites foram incluídas. Esses resultados concordariam com outros resultados semelhantes para costões rochosos no norte e no sul do Chile.

Spatial distribution of Echinolitorina peruviana (Lamarck, 1882) for intertidal rocky shore in Antofagasta (23° S, Chile) / Distribuição espacial de Echinolitorina peruviana (Lamarck, 1882) para costa rochosa entremarés em Antofagasta (23 ° S, Chile)

The intertidal rocky shores in continental Chile have high species diversity mainly in northern Chile (18-27° S), and one of the most widespread species is the gastropod Echinolittorina peruviana (Lamarck, 1822). The aim of the present study is do a first characterization of spatial distribution of E. peruviana in along rocky shore in Antofagasta town in northern Chile. Individuals were counted in nine different sites that also were determined their spectral properties using remote sensing techniques (LANDSAT ETM+). The results revealed that sites without marked human intervention have more abundant in comparison to sites located in the town, also in all studied sites was found an aggregated pattern, and in six of these sites were found a negative binomial distribution. The low density related to sites with human intervention is supported when spectral properties for sites were included. These results would agree with other similar results for rocky shore in northern and southern Chile.(AU)

As costas rochosas entremarés no Chile continental apresentam alta diversidade de espécies, principalmente no norte do país (18-27 ° S), e uma das espécies mais difundidas é o gastrópode Echinolittorina peruviana (Lamarck, 1822). O objetivo do presente estudo é fazer uma primeira caracterização da distribuição espacial de E. peruviana no costão rochoso da cidade de Antofagasta no norte do Chile. Os indivíduos foram contados em nove locais diferentes onde também foram determinadas suas propriedades espectrais usando técnicas de sensoriamento remoto (LANDSAT ETM +). Os resultados revelaram que os locais sem intervenção humana marcada apresentam maior abundância em comparação aos locais localizados no município. Também em todos os locais estudados foi encontrado um padrão agregado, sendo que em seis desses locais foi encontrada uma distribuição binomial negativa. A baixa densidade relacionada a sites com intervenção humana é suportada quando as propriedades espectrais para sites foram incluídas. Esses resultados concordariam com outros resultados semelhantes para costões rochosos no norte e no sul do Chile.(AU)

Sand Fly Fauna, Spatial Distribution of Lutzomyia longipalpis (Diptera: Psychodidae), and Climate Factors in Dourados, Brazil.

Studies of the geographic distribution of sand flies and the factors associated with their occurrence are necessary to understand the risk of leishmaniasis transmission. The objective of this study was to characterize the sand fly fauna, particularly the spatial distribution of Lutzomyia longipalpis (Lutz & Neiva), and correlate these with climate factors in the Dourados municipality, Brazil. The collection of sand flies was carried out with CDC Light Traps over two periods: at six sites for three consecutive nights each month from August 2012 to July 2013; and at four other sites for two consecutive nights each month from April 2017 to February 2018. We collected 591 sand flies in the first period and 121 in the second period for a total of 712 sand flies; 697 of the total collected were Lu. longipalpis. The minimum and maximum sand fly infestation rate (sites with vector presence) was 11.1% and 83.33% in the first period, and 0% and 50.0% in the second period. No sand flies with Leishmania were identified via PCR. Lu. longipalpis presented an aggregate disposition with excellent adjustment. Rainfall and relative humidity were the abiotic factors that influenced the vector infestation level. The aggregate distribution for this species was predicted by the environmental factors that favor the proliferation of Lu. longipalpis. The results of this study should assist in devising measures to control sand flies in Dourados, Brazil.

Accurate estimation for extra-Poisson variability assuming random effect models.

In this study, the components of extra-Poisson variability are estimated assuming random effect models under a Bayesian approach. A standard existing methodology to estimate extra-Poisson variability assumes a negative binomial distribution. The obtained results show that using the proposed random effect model it is possible to get more accurate estimates for the extra-Poisson variability components when compared to the use of a negative binomial distribution where it is possible to estimate only one component of extra-Poisson variability. Some illustrative examples are introduced considering real data sets.

Spatial distribution in marine invertebrates in rocky shore of Araucania Region (38° S, Chile) / Distribuição espacial em invertebrados marinhos na costa rochosa da região de Araucanía (38° S, Chile)

Abstract The rocky shores in Chile have a wide invertebrate species diversity, that include species with marked abundances in determined regions. The aim of the present study is to analyse the spatial distribution pattern in different marine invertebrate species in rocky shore of Araucania region, considering if these species have random, uniform or associated patterns, and extrapolate if these patterns have Poisson, binomial or negative binomial distribution respectively. The results revealed the presence mainly of gastropods molluscs that would graze on benthic algae, these species have mainly aggregated pattern that has a robust negative binomial distribution pattern. The obtained results agree with observations for marine benthic fauna that mentioned the presence of aggregated pattern, has negative binomial distribution. Other ecological topics about spatial distribution were discussed.

Resumo As costas rochosas no Chile têm uma ampla diversidade de espécies de invertebrados, que incluem espécies com abundância marcada em determinadas regiões. O objetivo do presente estudo é analisar o padrão de distribuição espacial em diferentes espécies de invertebrados marinhos na costa rochosa da região de Araucanía, considerando se essas espécies possuem padrões aleatórios, uniformes ou associados, e extrapolar se esses padrões possuem distribuição binomial de Poisson, binomial ou negativa. respectivamente. Os resultados revelaram a presença principalmente de moluscos gastrópodes que pastam em algas bentônicas, estas espécies têm principalmente agregado padrão que tem um padrão robusto de distribuição binomial negativa, padrão agregado de grupos, e a fauna de água doce que apresenta distribuição binomial negativa. Outros tópicos ecológicos sobre distribuição espacial foram discutidos.

Spatial distribution in marine invertebrates in rocky shore of Araucania Region (38° S, Chile) / Distribuição espacial em invertebrados marinhos na costa rochosa da região de Araucanía (38° S, Chile)

The rocky shores in Chile have a wide invertebrate species diversity, that include species with marked abundances in determined regions. The aim of the present study is to analyse the spatial distribution pattern in different marine invertebrate species in rocky shore of Araucania region, considering if these species have random, uniform or associated patterns, and extrapolate if these patterns have Poisson, binomial or negative binomial distribution respectively. The results revealed the presence mainly of gastropods molluscs that would graze on benthic algae, these species have mainly aggregated pattern that has a robust negative binomial distribution pattern. The obtained results agree with observations for marine benthic fauna that mentioned the presence of aggregated pattern, has negative binomial distribution. Other ecological topics about spatial distribution were discussed.(AU)

As costas rochosas no Chile têm uma ampla diversidade de espécies de invertebrados, que incluem espécies com abundância marcada em determinadas regiões. O objetivo do presente estudo é analisar o padrão de distribuição espacial em diferentes espécies de invertebrados marinhos na costa rochosa da região de Araucanía, considerando se essas espécies possuem padrões aleatórios, uniformes ou associados, e extrapolar se esses padrões possuem distribuição binomial de Poisson, binomial ou negativa. respectivamente. Os resultados revelaram a presença principalmente de moluscos gastrópodes que pastam em algas bentônicas, estas espécies têm principalmente agregado padrão que tem um padrão robusto de distribuição binomial negativa, padrão agregado de grupos, e a fauna de água doce que apresenta distribuição binomial negativa. Outros tópicos ecológicos sobre distribuição espacial foram discutidos.(AU)

Spatial distribution in marine invertebrates in rocky shore of Araucania Region (38° S, Chile)

Abstract The rocky shores in Chile have a wide invertebrate species diversity, that include species with marked abundances in determined regions. The aim of the present study is to analyse the spatial distribution pattern in different marine invertebrate species in rocky shore of Araucania region, considering if these species have random, uniform or associated patterns, and extrapolate if these patterns have Poisson, binomial or negative binomial distribution respectively. The results revealed the presence mainly of gastropods molluscs that would graze on benthic algae, these species have mainly aggregated pattern that has a robust negative binomial distribution pattern. The obtained results agree with observations for marine benthic fauna that mentioned the presence of aggregated pattern, has negative binomial distribution. Other ecological topics about spatial distribution were discussed.

Resumo As costas rochosas no Chile têm uma ampla diversidade de espécies de invertebrados, que incluem espécies com abundância marcada em determinadas regiões. O objetivo do presente estudo é analisar o padrão de distribuição espacial em diferentes espécies de invertebrados marinhos na costa rochosa da região de Araucanía, considerando se essas espécies possuem padrões aleatórios, uniformes ou associados, e extrapolar se esses padrões possuem distribuição binomial de Poisson, binomial ou negativa. respectivamente. Os resultados revelaram a presença principalmente de moluscos gastrópodes que pastam em algas bentônicas, estas espécies têm principalmente agregado padrão que tem um padrão robusto de distribuição binomial negativa, padrão agregado de grupos, e a fauna de água doce que apresenta distribuição binomial negativa. Outros tópicos ecológicos sobre distribuição espacial foram discutidos.

Social determinants of tuberculosis via a zero-inflated model in small areas of a city in Southeastern Brazil

Abstract INTRODUCTION: This study aimed to analyze social factors involved in the spatial distribution and under-reporting of tuberculosis (TB) in the city of Vitória, Espírito Santo State, Brazil. METHODS: This was an ecological study of the reported cases of TB between 2009 and 2011, according to census tracts. The outcome was TB incidence for the study period and the variables of exposure were proportions of literacy, inhabitants with an income of up to half the minimum monthly wage (MMW), and inhabitants associated with sewer mains or with access to safe drinking water. We used a zero-inflated process, zero-inflated negative binomial regression (ZINB), and selected an explanatory model based on the Akaike Information Criterion (AIC). RESULTS: A total of 588 cases of tuberculosis were reported in Vitória during the study period, distributed among 223 census tracts (38.6%), with 354 (61.4%) tracts presenting zero cases. In the ZINB model, the mean value of p i was 0.93, indicating that there is a 93% chance that an observed false zero could be due to sub-notification. CONCLUSIONS: It is important to prioritize areas exhibiting determinants that influence the occurrence of TB in the municipality of Vitória. The zero-inflated model can be useful to the public health sector since it identifies the percentage of false zeros, generating an estimate of the real epidemiological condition of TB in Vitória.

Incorporation of frailties into a cure rate regression model and its diagnostics and application to melanoma data.

Cure rate models have been widely studied to analyze time-to-event data with a cured fraction of patients. Our proposal consists of incorporating frailty into a cure rate model, as an alternative to the existing models to describe this type of data, based on the Birnbaum-Saunders distribution. Such a distribution has theoretical arguments to model medical data and has shown empirically to be a good option for their analysis. An advantage of the proposed model is the possibility to jointly consider the heterogeneity among patients by their frailties and the presence of a cured fraction of them. In addition, the number of competing causes is described by the negative binomial distribution, which absorbs several particular cases. We consider likelihood-based methods to estimate the model parameters and to derive influence diagnostics for this model. We assess local influence on the parameter estimates under different perturbation schemes. Deriving diagnostic tools is needed in all statistical modeling, which is another novel aspect of our proposal. Numerical evaluation of the considered model is performed by Monte Carlo simulations and by an illustration with melanoma data, both of which show its good performance and its potential applications. Particularly, the illustration confirms the importance of statistical diagnostics in the modeling.

Spatial distribution of nymphs and adults of Euschistus heros (Fabricius, 1794) (Heteroptera: Pentatomidae) in transgenic soybean cultivars of different maturing cycles / Distribuição espacial de ninfas e adultos de Euschistus heros (Fabricius, 1794) (Heteroptera: Pentatomidae) em cultivares transgênicas de soja de diferentes ciclos de desenvolvimento

The neotropical stink bug Euschistus heros is the predominant and most important insect pest affecting soybean cultivation. Knowledge of the spatial pattern of the pest in an area is critical to understanding its behavior. The objective of this work was to study the spatial distribution of E. heros in transgenic soybean cultivars of different maturing cycles. The experiments were conducted in the seasons 2013/14 and 2014/15 in FCAV/UNESP, Jaboticabal, SP. Three fields were selected, and each was marked an area of 8.000 m² (0.8 ha), with each area divided into 80 portions of 100 m2 (10 m x 10 m). The transgenic soybean cultivars of different maturing cycles were: SYN 1365 RR (early), M 7908 RR (average), and BRS Valiosa RR (late). Samples were taken weekly using a beat sheet, registering the number of nymphs and adults of E. heros. To study the dispersion of E. heros, the following indices were used: variance/mean ratio, Morisita index, Green coefficient, and the exponent k of the negative binomial distribution. For studies of special distribution models of E. heros, adjustments of Poisson distribution and negative binomial distribution were tested. The spatial distribution of nymphs and adults was aggregated for all the cultivars studied, indicating that cultivars did not alter the distribution behavior of E. heros.(AU)

O percevejo-marrom-da-soja Euschistus heros, destaca-se como o inseto-praga predominante e mais importante na cultura. O conhecimento do padrão espacial da praga na área é fundamental para o entendimento do seu comportamento. O objetivo do presente trabalho foi estudar a distribuição espacial de E. heros em cultivares de soja transgênica de diferentes ciclos de desenvolvimento. Os experimentos foram conduzidos nos anos agrícolas 2013/14 e 2014/15 na FCAV/UNESP, Jaboticabal, SP. Foram selecionados três campos, e em cada um foi demarcada uma área de 8.000 m² (0,8 ha), sendo cada área subdividida em 80 parcelas de 100 m² (10 m x 10 m). As cultivares de soja transgênica de diferentes ciclos de desenvolvimento utilizadas foram: SYN 1365 RR (precoce), M 7908 RR (média) e BRS Valiosa RR (tardia). As amostragens foram realizadas semanalmente usando pano de batida, registrando-se o número de ninfas e adultos. Para o estudo da dispersão de E. heros foram utilizados os seguintes índices: razão variância/média, índice de Morisita, coeficiente de Green e o expoente k da distribuição binomial negativa. Para os estudos dos modelos de distribuição espacial de E. heros foram testados os ajustes das distribuições de Poisson e distribuição binomial negativa. A distribuição espacial de ninfas e adultosfoi agregada para todas as cultivares em estudo, ou seja, as cultivares não alteram o comportamento de distribuição de E. heros.(AU)

Spatial distribution of nymphs and adults of Euschistus heros (Fabricius, 1794) (Heteroptera: Pentatomidae) in transgenic soybean cultivars of different maturing cycles / Distribuição espacial de ninfas e adultos de Euschistus heros (Fabricius, 1794) (Heteroptera: Pentatomidae) em cultivares transgênicas de soja de diferentes ciclos de desenvolvimento

The neotropical stink bug Euschistus heros is the predominant and most important insect pest affecting soybean cultivation. Knowledge of the spatial pattern of the pest in an area is critical to understanding its behavior. The objective of this work was to study the spatial distribution of E. heros in transgenic soybean cultivars of different maturing cycles. The experiments were conducted in the seasons 2013/14 and 2014/15 in FCAV/UNESP, Jaboticabal, SP. Three fields were selected, and each was marked an area of 8.000 m² (0.8 ha), with each area divided into 80 portions of 100 m2 (10 m x 10 m). The transgenic soybean cultivars of different maturing cycles were: SYN 1365 RR (early), M 7908 RR (average), and BRS Valiosa RR (late). Samples were taken weekly using a beat sheet, registering the number of nymphs and adults of E. heros. To study the dispersion of E. heros, the following indices were used: variance/mean ratio, Morisita index, Green coefficient, and the exponent k of the negative binomial distribution. For studies of special distribution models of E. heros, adjustments of Poisson distribution and negative binomial distribution were tested. The spatial distribution of nymphs and adults was aggregated for all the cultivars studied, indicating that cultivars did not alter the distribution behavior of E. heros.

O percevejo-marrom-da-soja Euschistus heros, destaca-se como o inseto-praga predominante e mais importante na cultura. O conhecimento do padrão espacial da praga na área é fundamental para o entendimento do seu comportamento. O objetivo do presente trabalho foi estudar a distribuição espacial de E. heros em cultivares de soja transgênica de diferentes ciclos de desenvolvimento. Os experimentos foram conduzidos nos anos agrícolas 2013/14 e 2014/15 na FCAV/UNESP, Jaboticabal, SP. Foram selecionados três campos, e em cada um foi demarcada uma área de 8.000 m² (0,8 ha), sendo cada área subdividida em 80 parcelas de 100 m² (10 m x 10 m). As cultivares de soja transgênica de diferentes ciclos de desenvolvimento utilizadas foram: SYN 1365 RR (precoce), M 7908 RR (média) e BRS Valiosa RR (tardia). As amostragens foram realizadas semanalmente usando pano de batida, registrando-se o número de ninfas e adultos. Para o estudo da dispersão de E. heros foram utilizados os seguintes índices: razão variância/média, índice de Morisita, coeficiente de Green e o expoente k da distribuição binomial negativa. Para os estudos dos modelos de distribuição espacial de E. heros foram testados os ajustes das distribuições de Poisson e distribuição binomial negativa. A distribuição espacial de ninfas e adultosfoi agregada para todas as cultivares em estudo, ou seja, as cultivares não alteram o comportamento de distribuição de E. heros.

Sequential Sampling Plan of Anthonomus grandis (Coleoptera: Curculionidae) in Cotton Plants.

The boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), is one of the most important pests of cotton production worldwide. The objective of this work was to develop a sequential sampling plan for the boll weevil. The studies were conducted in Maracaju, MS, Brazil, in two seasons with cotton cultivar FM 993. A 10,000-m2 area of cotton was subdivided into 100 of 10- by 10-m plots, and five plants per plot were evaluated weekly, recording the number of squares with feeding + oviposition punctures of A. grandis in each plant. A sequential sampling plan by the maximum likelihood ratio test was developed, using a 10% threshold level of squares attacked. A 5% security level was adopted for the elaboration of the sequential sampling plan. The type I and type II error used was 0.05, recommended for studies with insects. The adjustment of the frequency distributions used were divided into two phases, so that the model that best fit to the data was the negative binomial distribution up to 85 DAE (Phase I), and from there the best fit was Poisson distribution (Phase II). The equations that define the decision-making for Phase I are S0 = -5.1743 + 0.5730N and S1 = 5.1743 + 0.5730N, and for the Phase II are S0 = -4.2479 + 0.5771N and S1 = 4.2479 + 0.5771N. The sequential sampling plan developed indicated the maximum number of sample units expected for decision-making is ∼39 and 31 samples for Phases I and II, respectively.

Spatial distribution in marine invertebrates in rocky shore of Araucania Region (38° S, Chile)

Abstract The rocky shores in Chile have a wide invertebrate species diversity, that include species with marked abundances in determined regions. The aim of the present study is to analyse the spatial distribution pattern in different marine invertebrate species in rocky shore of Araucania region, considering if these species have random, uniform or associated patterns, and extrapolate if these patterns have Poisson, binomial or negative binomial distribution respectively. The results revealed the presence mainly of gastropods molluscs that would graze on benthic algae, these species have mainly aggregated pattern that has a robust negative binomial distribution pattern. The obtained results agree with observations for marine benthic fauna that mentioned the presence of aggregated pattern, has negative binomial distribution. Other ecological topics about spatial distribution were discussed.

Resumo As costas rochosas no Chile têm uma ampla diversidade de espécies de invertebrados, que incluem espécies com abundância marcada em determinadas regiões. O objetivo do presente estudo é analisar o padrão de distribuição espacial em diferentes espécies de invertebrados marinhos na costa rochosa da região de Araucanía, considerando se essas espécies possuem padrões aleatórios, uniformes ou associados, e extrapolar se esses padrões possuem distribuição binomial de Poisson, binomial ou negativa. respectivamente. Os resultados revelaram a presença principalmente de moluscos gastrópodes que pastam em algas bentônicas, estas espécies têm principalmente agregado padrão que tem um padrão robusto de distribuição binomial negativa, padrão agregado de grupos, e a fauna de água doce que apresenta distribuição binomial negativa. Outros tópicos ecológicos sobre distribuição espacial foram discutidos.

Co-Infestation and Spatial Distribution of Bactrocera carambolae and Anastrepha spp. (Diptera: Tephritidae) in Common Guava in the Eastern Amazon.

Field infestation and spatial distribution of introduced Bactrocera carambolae Drew and Hancock and native species of Anastrepha in common guavas [Psidium guajava (L.)] were investigated in the eastern Amazon. Fruit sampling was carried out in the municipalities of Calçoene and Oiapoque in the state of Amapá, Brazil. The frequency distribution of larvae in fruit was fitted to the negative binomial distribution. Anastrepha striata was more abundant in both sampled areas in comparison to Anastrepha fraterculus (Wiedemann) and B. carambolae The frequency distribution analysis of adults revealed an aggregated pattern for B. carambolae as well as for A. fraterculus and Anastrepha striata Schiner, described by the negative binomial distribution. Although the populations of Anastrepha spp. may have suffered some impact due to the presence of B. carambolae, the results are still not robust enough to indicate effective reduction in the abundance of Anastrepha spp. caused by B. carambolae in a general sense. The high degree of aggregation observed for both species suggests interspecific co-occurrence with the simultaneous presence of both species in the analysed fruit. Moreover, a significant fraction of uninfested guavas also indicated absence of competitive displacement.

Mortalidade por câncer do colo do útero no estado do Rio Grande do Norte, no período de 1996 a 2010: tendência temporal e projeções até 2030 / Cervical cancer mortality in the state of Rio Grande do Norte, Brazil, 1996-2010: time trends and projections up to 2030 / Mortalidad por cáncer de cuello de útero en el estado de Rio Grande del Norte, en el período de 1996 a 2010: tendencia temporal y proyecciones hasta el año 2030

OBJETIVO: analisar a tendência da mortalidade por câncer do colo do útero no estado do Rio Grande do Norte e em suas microrregiões de saúde, no período de 1996 a 2010, e realizar projeções para os quinquênios, de 2011 a 2030. MÉTODOS: estudo ecológico de series temporais; empregou-se regressão binomial negativa para análise das tendências e projeções. RESULTADOS: foram observadas taxas acima de 5,0 óbitos por 100 mil mulheres em todas as microrregiões, com tendência estacionária para o estado e ascendente nas microrregiões com piores condições socioeconômicas; as projeções indicaram redução nas taxas de mortalidade no estado, de 5,95/100 mil mulheres (2006-2010) para 3,67 (2026-2030), embora seja previsto aumento de 22% no número absoluto de óbitos. CONCLUSÃO: apesar da previsão de redução nas taxas de mortalidade, estas ainda apresentam-se elevadas, sinalizando a necessidade de revisão e fortalecimento do programa de controle do câncer do colo do útero no estado.

OBJECTIVE: to analyze cervical cancer mortality trends in the state of Rio Grande do Norte and its health micro-regions from 1996 to 2010, as well as to make projections for five-year periods from 2011 to 2030. METHODS: this was an ecological time series study; negative binomial regression was used to analyze trends and projections. RESULTS: rates above 5.0 deaths per 100,000 women were observed in all the micro-regions, with a stationary trend in the state as a whole and an upward trend in the micro-regions with the worst socioeconomic conditions; projections indicated reduction in mortality rates in the state, from 5.95/100,000 women (2006-2010) to 3.67 (2026-2030), although a 22% increase in the absolute number of deaths is expected. CONCLUSION: although a reduction in mortality rates is projected, they continue to be high, indicating the need for review and strengthening of the state's cervical cancer control program.

OBJETIVO: analizar la tendencia de mortalidad por cáncer de cuello de útero en el estado de Rio Grande del Norte (RN) y en sus microrregiones de salud, en el período de 1996 a 2010, así como realizar proyecciones para los períodos quinquenales entre 2011 y 2030. MÉTODOS: estudio ecológico de series de tiempo; se utilizó regresión binomial negativa para analizar tendencias y proyecciones. RESULTADOS: observamos tasas de 5.0 muertes por cada 100 mil mujeres en todas las microrregiones, con una tendencia estacionaria para el estado y ascendente en las microrregiones con peores condiciones socioeconómicas. Las proyecciones mostraron una reducción en las tasas de mortalidad en el estado, de 5.95/100 mil mujeres (2006-2010) para 3.67 (2026-2030), aunque se espere un aumento de 22% en el número absoluto de muertes. CONCLUSIÓN: a pesar del pronóstico de reducción de las tasas de mortalidad, estas siguen siendo altas, lo que indica la necesidad de revisar y fortalecer el programa de control de cáncer de cuello uterino en el estado.

Spatial Distribution of Adults of Triozoida limbata (Enderlein) (Hemiptera: Triozidae) in Guava Plants.

The psyllid Triozoida limbata (Enderlein) (Hemiptera: Triozidae) is a major pest in guava, feeding primarily on new shoots. Despite its importance, there are no studies on the spatial distribution of T. limbata on guava. Such studies are needed to establish sequential sampling plans for decision making in pest control. Thus, an experiment was carried out in a 9-year-old commercial guava orchard divided into 100 sampling units or plots. Double-sided yellow sticky traps were placed on one plant per plot (sample unit) to capture and monitor T. limbata adults from April 2011 to May 2012. To determine the insect distribution in the area, we calculated the variance-to-mean ratio index (I), the Morisita index (I δ ), Green's coefficient (Cx), and the k exponent of the negative binomial distribution. Most of the samples showed that the adults had a moderate to highly aggregated distribution. Statistical models were also used to study the pest spatial distribution by fitting the number of adults captured to the Poisson and negative binomial distributions. The negative binomial distribution model best fitted the data of the number of adult psyllids captured by the traps, which is consistent with an aggregated distribution.

Use of a negative binomial distribution to describe the presence of Sphyrion laevigatum in Genypterus blacodes / Uso de distribuição binomial negativa para descrever a presença de Sphyrion laevigatum em Genypterus blacodes

This paper describes the frequency and number of Sphyrion laevigatum in the skin of Genypterus blacodes, an important economic resource in Chile. The analysis of a spatial distribution model indicated that the parasites tended to cluster. Variations in the number of parasites per host could be described by a negative binomial distribution. The maximum number of parasites observed per host was two.

Este artigo descreve a frequência e o número de Sphyrion laevigatum da pele de Genypterus blacodes, o qual é um importante recurso econômico no Chile. A análise baseada em modelos de distribuição espacial, demonstrou que os parasitos tendem a ficar agrupados. A variação numérica de parasitas por hospedeiro pode ser descrita por distribuição binomial negativa. O número máximo observado de parasitas por hospedeiro foi dois.

The destructive negative binomial cure rate model with a latent activation scheme.

A new flexible cure rate survival model is developed where the initial number of competing causes of the event of interest (say lesions or altered cells) follow a compound negative binomial (NB) distribution. This model provides a realistic interpretation of the biological mechanism of the event of interest as it models a destructive process of the initial competing risk factors and records only the damaged portion of the original number of risk factors. Besides, it also accounts for the underlying mechanisms that leads to cure through various latent activation schemes. Our method of estimation exploits maximum likelihood (ML) tools. The methodology is illustrated on a real data set on malignant melanoma, and the finite sample behavior of parameter estimates are explored through simulation studies.