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Although biological invasions are a common and intensively studied phenomenon, most studies often ignore the biotic interactions that invasive species play in the environment. Here, we evaluated how and why invasive plant species are interconnected within the overall frugivory network of the Brazilian Atlantic Forest, an important global biodiversity hotspot. To do this, we used the recently published Atlantic Frugivory Dataset to build a meta-network (i.e., a general network made of several local networks) that included interactions between 703 native and invasive plant species and 331 frugivore species. Using tools derived from complex network theory and a bootstrap simulation approach, we found that the general structure of the Atlantic Forest frugivory network (i.e., nestedness and modularity) is robust against the entry of invasive plant species. However, we observed that invasive plant species are highly integrated within the frugivory networks, since both native and invasive plant species play similar structural roles (i.e., plant status is not strong enough to explain the interactive roles of plant species). Moreover, we found that plants with smaller fruits and with greater lipid content play a greater interactive role, regardless of their native or invasive status. Our findings highlight the biotic homogenization involving plant-frugivore interactions in the Atlantic Forest and that the impacts and consequences of invasive plant species on native fauna can be anticipated based on the characteristics of their fruits.
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OBJECTIVE: To stratify ultrasound samples in a pediatric population undergoing evaluation for acute appendicitis to examine the variability in cecal appendix diameter, in different age groups, and to determine whether there is a prevalent value for each age group. METHODS: A retrospective cross-sectional study with 196 children aged 0 to 15 years. Data were extracted from reports of ultrasound examinations carried out between 2008 and 2015. Children with sonographic diagnosis of appendicitis or other signs of periappendiceal inflammation were excluded. RESULTS: The evaluation of the anteroposterior measurement of the cecal appendix revealed a mean diameter of 4.14mm (standard deviation: 0.93mm; 95%CI: 3.86-4.14). Cecal appendix diameter did not differ significant between age groups. CONCLUSION: Evaluation of the anteroposterior diameter of the cecal appendix in centimeters in a sample of 196 children aged 0 to15 years revealed a mean diameter of 4.14mm (standard deviation, 0.93mm. There were no significant differences in cecal appendix diameter following stratification by age. Results indicate a single value can be adopted for mean cecal appendix diameter in pediatric populations.
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Apendicite , Apêndice , Apendicite/diagnóstico por imagem , Apêndice/diagnóstico por imagem , Criança , Estudos Transversais , Humanos , Estudos Retrospectivos , UltrassonografiaRESUMO
Trophic specialisation is known to vary across space, but the environmental factors explaining such variation remain elusive. Here we used a global dataset of flower-visitor networks to evaluate how trophic specialisation varies between latitudinal zones (tropical and temperate) and across elevation gradients, while considering the environmental variation inherent in these spatial gradients. Specifically, we assessed the role of current (i.e., net primary productivity, temperature, and precipitation) and historical (i.e., temperature and precipitation stability) environmental factors in structuring the trophic specialisation of floral visitors. Spatial variations in trophic specialisation were not explained by latitudinal zones or elevation. Moreover, regardless of network location on the spatial gradient, there was a tendency for higher trophic specialisation in sites with high productivity and precipitation, whereas historical temperature stability was related to lower trophic specialisation. We highlight that both energetic constraints in animal foraging imposed by climate and resource availability may drive the global variation in trophic specialisation.
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Clima , Flores , Animais , Estado NutricionalRESUMO
ABSTRACT Objective To stratify ultrasound samples in a pediatric population undergoing evaluation for acute appendicitis to examine the variability in cecal appendix diameter, in different age groups, and to determine whether there is a prevalent value for each age group. Methods A retrospective cross-sectional study with 196 children aged 0 to 15 years. Data were extracted from reports of ultrasound examinations carried out between 2008 and 2015. Children with sonographic diagnosis of appendicitis or other signs of periappendiceal inflammation were excluded. Results The evaluation of the anteroposterior measurement of the cecal appendix revealed a mean diameter of 4.14mm (standard deviation: 0.93mm; 95%CI: 3.86-4.14). Cecal appendix diameter did not differ significant between age groups. Conclusion Evaluation of the anteroposterior diameter of the cecal appendix in centimeters in a sample of 196 children aged 0 to15 years revealed a mean diameter of 4.14mm (standard deviation, 0.93mm. There were no significant differences in cecal appendix diameter following stratification by age. Results indicate a single value can be adopted for mean cecal appendix diameter in pediatric populations.
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Mexico is one of the most biodiverse countries in the world, with an important proportion of endemism mainly because of the convergence of the Nearctic and Neotropical biogeographic regions, which generate great diversity and species turnover at different spatial scales. However, most of our knowledge of the Mexican ant biota is limited to a few well-studied taxa, and we lack a comprehensive synthesis of ant biodiversity information. For instance, most of the knowledge available in the literature on Mexican ant fauna refers only to species lists by states, or is focused on only a few regions of the country, which prevents the study of several basic and applied aspects of ants, from diversity and distribution to conservation. Our aims in this data paper are therefore (1) to compile all the information available regarding ants across the Mexican territory, and (2) to identify major patterns in the gathered data set and geographic gaps in order to direct future sampling efforts. All records were obtained from raw data, including both unpublished and published information. After exhaustive filtering and updating information and synonyms, we compiled a total of 21,731 records for 887 ant species distributed throughout Mexico from 1894 to 2018. These records were concentrated mainly in the states of Chiapas (n = 6,902, 32.76%) and Veracruz de Ignacio de la Llave (n = 4,329, 19.92%), which together comprise half the records. The subfamily with the highest number of records was Myrmicinae (n = 10,458 records, 48.12%), followed by Formicinae (n = 3,284, 15.11%) and Ponerinae (n = 1,914, 8.8%). Most ant records were collected in the Neotropical region of the country (n = 12,646, 58.19%), followed by the Mexican transition zone (n = 5,237, 24.09%) and the Nearctic region (n = 3,848, 17.72%). Native species comprised 95.46% of the records (n = 20,745). To the best of our knowledge, this is the most complete data set available to date in the literature for the country. We hope that this compilation will encourage researchers to explore different aspects of the population and community research of ants at different spatial scales, and to aid in the establishment of conservation policies and actions. There are no copyright restrictions. Please cite this data paper when using its data for publications or teaching events.
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Formigas , Animais , Biodiversidade , Biota , Incidência , MéxicoRESUMO
In the last years, there were a growing number of studies using the metric H 2' to calculate complementary specialization in host-parasite interaction networks. However, only a few studies have explored the sensitivity of H 2' to network dimensions (i.e. species richness and number of interactions), which consequently could generate studies that are not comparable among them or lead to biased conclusions. In this study, we used the recent published study conducted by Rivera-García et al. in 2016 involving host-bat fly networks as an example to call attention to the risk of using H 2' to calculate specialization for small matrices. After conducting analyses based on both empirical and simulated data, we show that H 2' values are strongly affected by randomly allocation of species interactions to another cell in the matrix for small networks and that therefore the results and conclusions presented in Rivera-García et al. in 2016 are only an artefact of the dataset used. Therefore, we fully recommended taking into account the careful use of small networks to measuring specialization in host-parasite interactions.
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Quirópteros/parasitologia , Dípteros/fisiologia , Interações Hospedeiro-Parasita , Animais , Especificidade de Hospedeiro , Modelos BiológicosRESUMO
El carcinoma colorrectal es una causa importante de muerte relacionada con cáncer en América Latina y su incidencia aumenta en la medida que la población incrementa su edad por encima de la sexta década. Esta elevación de la incidencia y tasa de mortalidad han hecho que este carcinoma tenga un mayor interés en el área de investigación, pues la mortalidad puede disminuir si se detectan casos tempranos. El objetivo de este artículo es llamar la atención del clínico y del cirujano sobre la identificación de grupos de alto riesgo para el desarrollo de este cáncer, puesto que en estos grupos los métodos de escrutinio pueden ser bastante efectivos desde el punto devista costo-beneficio.