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1.
Curr Zool ; 70(4): 453-464, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39176064

RESUMO

Knowledge regarding the influence of individual traits on interaction patterns in nature can help understand the topological role of individuals within a network of intrapopulation interactions. We tested hypotheses on the relationships between individuals' positions within networks (specialization and centrality) of 4 populations of the mouse opossum Gracilinanus agilis and their traits (i.e., body length, body condition, tail length relative to body length, sex, reproductive condition, and botfly parasitism) and also seasonal effects in the Brazilian savanna. Individuals with lower body length, better body condition, and relatively shorter tail were more specialized (i.e., less connected within the network). Individuals were also more specialized and less connected during the warm-wet season. The relationship between individuals' position in the network and body traits, however, was independent of season. We propose that specialization may arise not only as a result of preferred feeding strategies by more capable individuals (i.e., those with better body condition and potentially prone to defend and access high-quality food resources) but also because of morphological constraints. Smaller/younger individuals (consequently with less experience in foraging) and short-tailed individuals (less skilled to explore the vertical strata of the vegetation) would feed only on a subset of the available food resources and consequently become more specialized. Moreover, individuals are more specialized during the warm-wet season because of high competition (population-dense period) and higher ecological opportunities (resource-rich period). Therefore, our study reveals the relevance of individual traits in shaping interaction patterns and specialization in populations.

2.
Entramado ; 20(1): 1-ene.-jun. 2024. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1574817

RESUMO

RESUMEN Este artículo tiene como objetivo desarrollar una herramienta computacional basada en la teoría de redes y vigilancia científico-tecnológica para fortalecer los procesos de investigación en una institución de educación superior: Corporación Universitaria Empresarial Alexander von Humboldt en Colombia. Se construyeron dos redes: una de investigadores y coinvestigadores, y otra de palabras clave de proyectos de investigación. El análisis de centralidad reveló grupos de colaboración interdisciplinarios y la existencia de investigadores aislados. Los resultados destacan la importancia de fomentar la colaboración entre investigadores y la interdisciplinariedad. Se proponen futuras investigaciones para mejorar la herramienta y su aplicación en la toma de decisiones estratégicas en una Institución de Educación Superior Esta aproximación basada en redes complejas proporciona percepciones sobre la investigación en la institución y su potencial para enriquecer la producción investigativa y el desarrollo tecnológico.


AВSTRАСT The objective of this article is to develop a computational tool based on network theory and scientific-technological surveillance to strengthen research processes in a higher education institution, case study: The Alexander von Humboldt University Business Corporation in Colombia. Two networks were constructed: one of researchers and co-researchers, and another of keywords of research projects. The centrality analysis revealed interdisciplinary collaborative groups and the existence of isolated researchers. The results highlight the importance of fostering collaboration among researchers and interdisciplinarity Future research is proposed to improve the tool and its application in strategic decision-making in a Higher Education Institution. This approach based on complex networks provides insights about research in the institution and its potential to enrich research production and technological development.


RESUMO Este artigo tem como objetivo desenvolver uma ferramenta computacional baseada na teoria de redes e na vigilância científico-tecnológica para fortalecer os processos de pesquisa em uma instituição de ensino superior, estudo de caso da Corporación Universitaria Empresarial Alexander von Humboldt na Colômbia. Foram construídas duas redes: uma de pesquisadores e co-pesquisadores e outra de palavras-chave de projetos de pesquisa. A análise de centralidade revelou grupos colaborativos interdisciplinares e a existência de pesquisadores isolados. Os resultados destacam a importância de promover a colaboração entre pesquisadores e a interdisciplinaridade. Propõe-se uma pesquisa futura para aprimorar a ferramenta e sua aplicação na tomada de decisões estratégicas em uma instituição de ensino superior Essa abordagem de rede complexa fornece percepções sobre a pesquisa na instituição e seu potencial para enriquecer a produção de pesquisa e o desenvolvimento tecnológico.

3.
J Anim Ecol ; 93(8): 1123-1134, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-38877697

RESUMO

Metacommunity processes have the potential to determine most features of the community structure. However, species diversity has been the dominant focus of studies. Nestedness, modularity and checkerboard distribution of species occurrences are main components of biodiversity organisation. Within communities, these patterns emerge from the interaction between functional diversity, spatial heterogeneity and resource availability. Additionally, the connectivity determines the pool of species for community assembly and, eventually, the pattern of species co-occurrence within communities. Despite the recognised theoretical expectations, the change in occurrence patterns within communities along ecological gradients has seldom been considered. Here, we analyse the spatial occurrence of animal species along sampling units within 18 temporary ponds and its relationship with pond environments and geographic isolation. Isolated ponds presented a nested organisation of species with low spatial segregation-modularity and checkerboard-and the opposite was found for communities with high connectivity. A pattern putatively explained by high functional diversity in ponds with large connectivity and heterogeneity, which determines that species composition tracks changes in microhabitats. On the contrary, nestedness is promoted in dispersal-limited communities with low functional diversity, where microhabitat filters mainly affect richness without spatial replacement between functional groups. Vegetation biomass promotes nestedness, probably due to the observed increase in spatial variance in biomass with the mean biomass. Similarly, the richness of vegetation reduced the spatial segregation of animals within communities. This result may be due to the high plant diversity of the pond that is observed similarly along all sampling units, which promotes the spatial co-occurrence of species at this scale. In the study system, the spatial arrangement of species within communities is related to local drivers as heterogeneity and metacommunity processes by means of dispersal between communities. Patterns of species co-occurrence are interrelated with community biodiversity and species interactions, and consequently with most functional and structural properties of communities. These results indicate that understanding the interplay between metacommunity processes and co-occurrence patterns is probably more important than previously thought to understand biodiversity assembly and functioning.


Los procesos metacomunitarios tienen el potencial de determinar la mayoría de las características de la estructura de las comunidades. Sin embargo, los trabajos se han enfocado principalmente en los patrones de diversidad de especies. El anidamiento, la modularidad y la distribución en damero de la ocurrencia espacial de las especies son propiedades básicas de las comunidades. Estos patrones surgen de la interacción entre la diversidad funcional, la heterogeneidad espacial y la disponibilidad de recursos dentro de las comunidades. Además, el pool de especies disponibles para el ensamblaje está determinado por la conectividad de la comunidad, afectando así su patrón de co­ocurrencia de especies. A pesar de las reconocidas expectativas teóricas, el cambio en los patrones de ocurrencia dentro de las comunidades a lo largo de gradientes ecológicos ha sido poco considerado. Aquí, analizamos la ocurrencia espacial de especies animales dentro de 18 charcos temporales y su relación con las características ambientales y el aislamiento geográfico de los charcos. Los charcos aislados presentaron alto anidamiento espacial mientras que los charcos de alta conectividad una distribución de ocurrencias modular y en damero. Por un lado, la baja diversidad funcional en charcos aislados, determinaría que los filtros microambientales afecten la riqueza de especies sin reemplazo espacial entre grupos funcionales, promoviendo un arreglo anidado de ocurrencias. Por otro lado, la alta diversidad funcional en charcos con alta conectividad y heterogeneidad permitiría el reemplazo espacial de especies en gradientes microambientales, determinando los patrones de segregación observados. La biomasa vegetal promueve el anidamiento, probablemente debido al aumento observado en la variación espacial de la biomasa con la biomasa media. La riqueza vegetal también redujo la segregación espacial de los animales dentro de las comunidades. Este resultado puede deberse a que la alta diversidad de plantas de los charcos es también observada a nivel de unidades muestreales, favoreciendo esto la coexistencia espacial de especies. El arreglo espacial de especies dentro de las comunidades estudiadas estaría determinado tanto por factores locales como la heterogeneidad, como por procesos regionales operando a través de la dispersión de individuos entre comunidades. Los patrones de co­ocurrencia de especies están interrelacionados con la diversidad comunitaria y las interacciones bióticas, y consecuentemente con la mayoría de las propiedades estructurales y funcionales de las comunidades. Este estudio evidencia la importancia de la conexión entre procesos metacomunitarios y la co­ocurrencia espacial de especies para comprender el ensamblaje y funcionamiento de la biodiversidad.


Assuntos
Biodiversidade , Lagoas , Animais , Ecossistema , Biomassa
4.
Heliyon ; 10(5): e27278, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38562502

RESUMO

Protein-Protein Interaction Networks aim to model the interactome, providing a powerful tool for understanding the complex relationships governing cellular processes. These networks have numerous applications, including functional enrichment, discovering cancer driver genes, identifying drug targets, and more. Various databases make protein-protein networks available for many species, including Homo sapiens. This work topologically compares four Homo sapiens networks using a coarse-to-fine approach, comparing global characteristics, sub-network topology, specific nodes centrality, and interaction significance. Results show that the four human protein networks share many common protein-encoding genes and some global measures, but significantly differ in the interactions and neighbourhood. Small sub-networks from cancer pathways performed better than the whole networks, indicating an improved topological consistency in functional pathways. The centrality analysis shows that the same genes play different roles in different networks. We discuss how studies and analyses that rely on protein-protein networks for humans should consider their similarities and distinctions.

5.
J Anim Ecol ; 92(11): 2122-2125, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37908114

RESUMO

The current biodiversity crisis requires efficient approaches to address the ongoing impoverishment of natural communities and the depletion of ecosystem services and functions. In this sense, identifying key species that promote the functioning of ecological processes can be strategic to guide actions aiming at the conservation and restoration of biodiversity. Node-level metrics in interaction networks can be helpful to identify those key species, as they measure the role each species plays in organizing the interactions. Moreover, ecological correlates of species structural roles may vary between local and global networks of interactions, reflecting distinct mechanisms acting at different spatial scales. By studying local seed dispersal networks and one global meta-network combining those local networks, Moulatlet et al. identified the most important traits explaining bird species centrality at varying spatial scales. They found that body mass was the main trait explaining centrality at the local scale, whereas range size was the main predictor of species centrality at the global scale. In this contribution, besides assessing local interaction networks, Moulatlet et al. adopt a biogeographical perspective to seed dispersal systems, extending our knowledge about the possible mechanisms that underlie the organization of interacting assemblages when changing the spatial scale of observation. Future efforts on this field could include an intermediate scale, comprising the level of metacommunities, shedding light on the interplay between local and spatial processes, both embedded in biogeographical realms, when determining the organization of interactions and the ecological correlates of species roles.


A atual crise da biodiversidade requer abordagens eficientes para lidar com o empobrecimento contínuo das comunidades naturais e com o esgotamento das funções e dos serviços ecossistêmicos. Neste sentido, identificar espécies-chave que promovam o funcionamento dos processos ecológicos pode ser estratégico para guiar ações que visam a conservação e a restauração da biodiversidade. Métricas em nível dos nós em redes de interação podem ser úteis para identificar tais espécies-chave, já que quantificam o papel que cada espécie desempenha em organizar as interações. Além disso, os correlatos ecológicos dos papéis estruturais das espécies podem variar entre redes de interações locais e globais, refletindo os distintos mecanismos que atuam em diferentes escalas espaciais. Ao estudar redes de dispersão de sementes locais e uma meta-rede global que combina essas redes locais, Moulatlet et al. identificaram as características mais importantes para explicar a centralidade das espécies de aves em diferentes escalas espaciais. Eles encontraram a massa corporal como principal característica que explicava a centralidade na escala local, enquanto o tamanho da distribuição foi o principal preditor da centralidade das espécies na escala global. Nesta contribuição, além de avaliar redes de interação locais, Moulatlet et al. adotaram uma perspectiva biogeográfica ao tratar os sistemas de dispersão de sementes, ampliando nosso conhecimento sobre os possíveis mecanismos subjacentes à organização das interações quando mudamos a escala espacial de observação. Esforços futuros neste campo poderiam incluir uma escala intermediária, compreendendo o nível de metacomunidades, buscando esclarecer as relações entre processos locais e processos espaciais, ambos inseridos em domínios biogeográficos, ao determinar a organização das interações e os correlatos ecológicos dos papéis estruturais das espécies.


Assuntos
Ecossistema , Dispersão de Sementes , Animais , Sementes , Biodiversidade , Aves
6.
Brain Sci ; 13(6)2023 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-37371383

RESUMO

Naturalistic paradigms are being increasingly applied to investigate human brain function. Compared with resting-state and task-based paradigms in neuroimaging, naturalistic stimuli and situations can be potentially more readily translated to daily-life applications. Among neuroimaging modalities, functional near-infrared spectroscopy (fNIRS) is particularly suitable for naturalistic investigations and applications. However, specific and tailored statistical analysis to interrogate brain function using naturalistic fNIRS is warranted. Here, we describe an exploratory graph-centrality-based approach to investigating participants' spatiotemporal similarities from the fNIRS signal. We illustrate the usefulness of our approach in a sample of typically developing children (10 males and 9 females; mean age of 5.2 years old; sd = 0.78) while they watch the Inscapes movie designed for neuroimaging acquisition. A node in the left dorsal prefrontal cortex presented similar responses across children, and those fNIRS responses were in line with scene transitions in the movie stimulus. Our results suggest the feasibility of applying centrality graph-based measures to investigate brain function in naturalistic fNIRS during development.

7.
Aging (Albany NY) ; 15(19): 9896-9912, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37074814

RESUMO

Dysregulated central-energy metabolism is a hallmark of brain aging. Supplying enough energy for neurotransmission relies on the neuron-astrocyte metabolic network. To identify genes contributing to age-associated brain functional decline, we formulated an approach to analyze the metabolic network by integrating flux, network structure and transcriptomic databases of neurotransmission and aging. Our findings support that during brain aging: (1) The astrocyte undergoes a metabolic switch from aerobic glycolysis to oxidative phosphorylation, decreasing lactate supply to the neuron, while the neuron suffers intrinsic energetic deficit by downregulation of Krebs cycle genes, including mdh1 and mdh2 (Malate-Aspartate Shuttle); (2) Branched-chain amino acid degradation genes were downregulated, identifying dld as a central regulator; (3) Ketone body synthesis increases in the neuron, while the astrocyte increases their utilization, in line with neuronal energy deficit in favor of astrocytes. We identified candidates for preclinical studies targeting energy metabolism to prevent age-associated cognitive decline.


Assuntos
Astrócitos , Metabolismo Energético , Astrócitos/metabolismo , Metabolismo Energético/genética , Transmissão Sináptica , Perfilação da Expressão Gênica , Glucose/metabolismo
8.
Entropy (Basel) ; 25(2)2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36832708

RESUMO

In this paper, the Sun and its behavior are studied by means of complex networks. The complex network was built using the Visibility Graph algorithm. This method maps time series into graphs in which every element of the time series is considered as a node and a visibility criterion is defined in order to connect them. Using this method, we construct complex networks for magnetic field and sunspots time series encompassing four solar cycles, and various measures such as degree, clustering coefficient, mean path length, betweenness centrality, eigenvector centrality and decay exponents were calculated. In order to study the system in several time scales, we perform both a global, where the network contains information on the four solar cycles, and a local analysis, involving moving windows. Some metrics correlate with solar activity, while others do not. Interestingly, those metric which seem to respond to varying levels of solar activity in the global analysis, also do in the moving windows analysis. Our results suggest that complex networks can provide a useful way to follow solar activity, and reveal new features on solar cycles.

9.
Parasitology ; 150(3): 262-268, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36529860

RESUMO

Interaction networks can provide detailed information regarding ecological systems, helping us understand how communities are organized and species are connected. The goals of this study were to identify the pattern of interaction between bats and ectoparasites in urban green areas of Grande Aracaju, Sergipe, and calculate connectance, specialization, nesting, modularity and centrality metrics. Bats were captured using 10 mist nets inside and on the edges of the fragments, and the collected ectoparasites were stored in 70% alcohol. All analyses were performed using R software. The interaction network consisted of 10 species of bats and 13 ectoparasites. Connectivity was considered low (0.12). The specialization indices for ectoparasites ranged from 0.50 to 1.00, and the value obtained for the network was 0.96, which is high. The observed nesting metric was low (wNODF = 1.47), whereas the modularity was high (wQ = 0.74), indicating that the studied network had a modular topology. All centrality metrics had low values. The observed modularity may have been caused by the evolutionary history of the bats and ectoparasites involved and the high specificity index of the interactions. The low centrality values may be associated with low connectivity and a high degree of specialization. This study provides relevant information on bat­parasite interactions in an urban environment, highlighting the need for further studies to improve our understanding of host­parasite interaction networks.


Assuntos
Quirópteros , Dípteros , Parasitos , Animais , Quirópteros/parasitologia , Brasil/epidemiologia , Ecossistema , Interações Hospedeiro-Parasita
10.
Artigo em Português | LILACS, Index Psicologia - Periódicos | ID: biblio-1537443

RESUMO

Partindo da noção de trabalho vivo, Christophe Dejours apresenta a tese da centralidade do trabalho para a subjetividade e a saúde mental. Para tanto, traz à baila a discussão sobre: a atividade, a insuficiência da tarefa e a experiência de fracasso diante do real; bem como a inteligência do corpo e a afetividade, marcando sua transformação à medida que realiza a atividade, em uma relação dinâmica entre o corpo, a subjetividade e a atividade. Não sendo o trabalho algo solipsista, tais elementos se entrecruzam em meio a outrem, o que requisita a cooperação e os aspectos complexos da formulação de regras para a própria atividade e demanda a confiança, a deliberação coletiva. É nesse coletivo, no viver juntos, que pode ocorrer o reconhecimento que, realizado sobre o que é feito, permite a realização de si no campo social, voltando-se para quem o faz, para uma identidade, que é o que protege a saúde mental. Na ausência da convivialidade e reconhecimento, o trabalho produz sofrimento patógeno. Desse modo, Dejours demonstra que nunca há neutralidade do trabalho no que diz respeito à subjetividade e à identidade, possibilitando a realização de si ou sua destruição


Based on the notion of living work, Christophe Dejours presents the thesis of the centrality of work for subjectivity and mental health. To do so, he discusses activity, the insufficiency of the task, the experience of failure in the face of reality, and the intelligence of the body and affectivity, marking its transformation as it performs the activity in a dynamic relationship between the body, subjectivity, and the activity. Rather than configuring a solipsistic text, such elements intersect each other, requiring cooperation and the complex aspects of formulating rules for the activity itself, which requires trust and collective deliberation. It is in this collective, in living together, that recognition can occur, which , based on what is done, enables self-realization in the social field, turning to those who do it and to an identity, which is what protects mental health. In the absence of conviviality and recognition, work produces pathogenic suffering. Thus, the author shows that work is never neutral toward subjectivity and identity, enabling self-realization or its own destruction


Assuntos
Trabalho , Saúde Mental
11.
Animals (Basel) ; 12(22)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36428421

RESUMO

This paper examines the role of women in the dual-purpose livestock system (DP) in Mexico through their technological adoption patterns and aims to evaluate whether there are significant differences between the technology adoption networks of men and women farmers. The sample was composed of 383 DP small farms with 20 or fewer cows and a high level of vulnerability. Social Network Analysis (SNA) was applied, and the centrality measures were calculated for the technological areas of management, feeding, genetics, reproduction, and animal health. Significant differences were found in reproduction levels between men and women farmers. Therefore, SNA was developed in this technological area where men mainly occupied central positions (brokers) while women were just close to the leaders in the network. The results have shown that farms run by women were smaller and presented higher levels of specialization and milk productivity (20% higher), and women prioritized those technologies linked to female reproductive efficiency. Moreover, women were deeply embedded in men's networks through numerous ties and were capable of building connections with groups of farmers outside of their own group.

12.
Front Comput Neurosci ; 16: 975743, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36185711

RESUMO

Hyperscanning is a promising tool for investigating the neurobiological underpinning of social interactions and affective bonds. Recently, graph theory measures, such as modularity, have been proposed for estimating the global synchronization between brains. This paper proposes the bootstrap modularity test as a way of determining whether a pair of brains is coactivated. This test is illustrated as a screening tool in an application to fNIRS data collected from the prefrontal cortex and temporoparietal junction of five dyads composed of a teacher and a preschooler while performing an interaction task. In this application, graph hub centrality measures identify that the dyad's synchronization is critically explained by the relation between teacher's language and number processing and the child's phonological processing. The analysis of these metrics may provide further insights into the neurobiological underpinnings of interaction, such as in educational contexts.

13.
Math Biosci Eng ; 19(7): 6731-6742, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35730280

RESUMO

People's attitudes and behaviors are partially shaped by the socioeconomic class to which they belong. In this work, a model of scale-free graph is proposed to represent the daily personal contacts in a society with three social classes. In the model, the probability of having a connection between two individuals depends on their social classes and on their physical distance. Numerical simulations are performed by considering sociodemographic data from France, Peru, and Zimbabwe. For the complex networks built for these three countries, average values of node degree, shortest-path length, clustering coefficient, closeness centrality, betweenness centrality, and eigenvector centrality are computed. These numerical results are discussed by taking into account the propagation of information about COVID-19.


Assuntos
COVID-19 , COVID-19/epidemiologia , Humanos , Fatores Socioeconômicos
14.
Comput Struct Biotechnol J ; 20: 1821-1828, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35521552

RESUMO

Genetic and omics analyses frequently require independent observations, which is not guaranteed in real datasets. When relatedness cannot be accounted for, solutions involve removing related individuals (or observations) and, consequently, a reduction of available data. We developed a network-based relatedness-pruning method that minimizes dataset reduction while removing unwanted relationships in a dataset. It uses node degree centrality metric to identify highly connected nodes (or individuals) and implements heuristics that approximate the minimal reduction of a dataset to allow its application to complex datasets. When compared with two other popular population genetics methodologies (PLINK and KING), NAToRA shows the best combination of removing all relatives while keeping the largest possible number of individuals in all datasets tested and also, with similar effects on the allele frequency spectrum and Principal Component Analysis than PLINK and KING. NAToRA is freely available, both as a standalone tool that can be easily incorporated as part of a pipeline, and as a graphical web tool that allows visualization of the relatedness networks. NAToRA also accepts a variety of relationship metrics as input, which facilitates its use. We also release a genealogies simulator software used for different tests performed in this study.

15.
Antibiotics (Basel) ; 11(3)2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35326864

RESUMO

Peptide-based drugs are promising anticancer candidates due to their biocompatibility and low toxicity. In particular, tumor-homing peptides (THPs) have the ability to bind specifically to cancer cell receptors and tumor vasculature. Despite their potential to develop antitumor drugs, there are few available prediction tools to assist the discovery of new THPs. Two webservers based on machine learning models are currently active, the TumorHPD and the THPep, and more recently the SCMTHP. Herein, a novel method based on network science and similarity searching implemented in the starPep toolbox is presented for THP discovery. The approach leverages from exploring the structural space of THPs with Chemical Space Networks (CSNs) and from applying centrality measures to identify the most relevant and non-redundant THP sequences within the CSN. Such THPs were considered as queries (Qs) for multi-query similarity searches that apply a group fusion (MAX-SIM rule) model. The resulting multi-query similarity searching models (SSMs) were validated with three benchmarking datasets of THPs/non-THPs. The predictions achieved accuracies that ranged from 92.64 to 99.18% and Matthews Correlation Coefficients between 0.894-0.98, outperforming state-of-the-art predictors. The best model was applied to repurpose AMPs from the starPep database as THPs, which were subsequently optimized for the TH activity. Finally, 54 promising THP leads were discovered, and their sequences were analyzed to encounter novel motifs. These results demonstrate the potential of CSNs and multi-query similarity searching for the rapid and accurate identification of THPs.

16.
Heliyon ; 8(1): e08661, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35036592

RESUMO

Comparative organizational network analysis makes it possible to identify the similarities and differences between organizations according to the content of their networks. This research is a comparative study of organizational networks based on formal power. To accomplish this goal, networks were developed in three organizations from different sectors with workers distributed in high, middle and operational levels in the organizational hierarchy. For the study, 100% of the workers within the identified networks were included. The results indicated that, considering centrality and connectivity network indices, there were no statistically significant differences between organizations according to formal power network behavior. However, we obtained statistically significant differences in terms connectivity and centrality considering the workers' hierarchy. The representative nodes of high and middle hierarchical levels had higher indices of connectivity and centrality than the nodes representative of the operational level. This study makes it possible to identify the formal roles within networks based on legitimate power, which can serve as a basis for decision-making processes and resource allocations, for the strategic use of the networks created.

17.
Mol Ecol ; 31(6): 1766-1782, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35048442

RESUMO

Non-native (invasive) species offer a unique opportunity to study the geographical distribution and range limits of species, wherein the evolutionary change driven by interspecific interactions between native and non-native closely related species is a key component. The red-eared slider turtle, Trachemys scripta elegans (TSE), has been introduced and successfully established worldwide. It can coexist with its native congeners T. cataspila, T. venusta and T. taylori in Mexico. We performed comprehensive fieldwork, executed a battery of genetic analyses and applied a novel species distribution modelling approach to evaluate their historical lineage relationships and contemporary population genetic patterns. Our findings support the historical common ancestry between native TSE and non-native (TSEalien ), while also highlighting the genetic differentiation of the exotic lineage. Genetic patterns are associated with their range size/endemism gradient; the microendemic T. taylori showed significant reduced genetic diversity and high differentiation, whereas TSEalien showed the highest diversity and signals of population size expansion. Counter to our expectations, lower naturally occurring distribution overlap and little admixture patterns were found between TSE and its congeners, exhibiting reduced gene flow and clear genetic separation across neighbouring species despite having zones of contact. We demonstrate that these native Trachemys species have distinct climatic niche suitability, probably preventing establishment of and displacement by the TSEalien . Moreover, we found major niche overlap between TSEalien and native species worldwide, supporting our prediction that sites with closer ecological optima to the invasive species have higher establishment risk than those that are closer to the niche-centre of the native species.


Assuntos
Tartarugas , Animais , Espécies Introduzidas , México , Tartarugas/genética
18.
Integr Zool ; 17(4): 530-542, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34498374

RESUMO

Interactions among living beings are the structuring basis of ecosystems, and studies of networks allow us to identify the patterns and consistency of such interactions. Antagonistic networks reflect the energy flow of communities, and identifying network structure and the biological aspects that influence its stability is crucial to understanding ecosystem functioning. We used antagonistic anuran interactions-predator-prey and host-parasite-to assess structural patterns and to identify the key anuran species structuring these networks. We tested whether anuran body-size and life-habit are related to their roles in these networks. We collected individuals of 9 species of anurans from an area of the Atlantic Forest in Brazil and identified their prey and helminth parasites. We used network (modularity, specialization, and nestedness) and centrality metrics (degree, closeness, and betweenness) to identify the role of anuran species in both networks. We then evaluated whether anuran body-size or life-habit were related to anuran centrality using generalized linear mixed models. The networks formed specialized interactions in compartments composed by key species from different habits. In our networks, anurans with rheophilic and cryptozoic habit are central in predator-prey networks, and those with larger body size and arboreal and cryptozoic habit in the host-parasite network. This study represents a step towards a better understanding of the influential factors that affect the structure of anuran antagonist networks, as well as to recognize the functioning roles of anuran species.


Assuntos
Ecossistema , Helmintos , Animais , Anuros , Tamanho Corporal , Hábitos
19.
J Health Care Chaplain ; 28(4): 555-565, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34709998

RESUMO

Although religiosity is a strong feature of Brazilian people, the integration of spirituality in palliative care (PC) has been a challenge for health care professionals. In order to evaluate the spiritual resources used by family members of patients in PC, this work presents the results of the research carried out with 50 family members. The Satisfaction with Life Scale, Centrality of Religiosity Scale, Spiritual/Religious Coping Scale, Religious and Spiritual Struggles Scale, and Attachment to God Inventory were applied. The prevalence of positive spiritual/religious coping was very high (76%) or high (6%). There was a strong correlation between positive spiritual/religious coping and centrality of religiosity (r = 0.805; SD = 0.87). There was a moderate negative correlation between the avoidant attachment to God and centrality of religiosity (r = -0.611; SD = 1.24) and positive spiritual/religious coping (r = -0.575; SD = 1.37). There was a moderate positive correlation between the anxious attachment to God and spiritual struggles (r = 0.515; SD = 0.76) and negative spiritual/religious coping (r = 0.555; SD = 0.616). These results suggest that spiritual/religious resources are present in family members of patients in PC. These resources have been mostly ignored by the multidisciplinary team. Findings provide an evidence base for training health care professionals to better integrate spirituality in PC settings.


Assuntos
Cuidados Paliativos , Qualidade de Vida , Adaptação Psicológica , Brasil , Família , Humanos , Espiritualidade
20.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;55: e12036, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1394129

RESUMO

The study of functional reorganization following stroke has been steadily growing supported by advances in neuroimaging techniques, such as functional magnetic resonance imaging (fMRI). Concomitantly, graph theory has been increasingly employed in neuroscience to model the brain's functional connectivity (FC) and to investigate it in a variety of contexts. The aims of this study were: 1) to investigate the reorganization of network topology in the ipsilesional (IL) and contralesional (CL) hemispheres of stroke patients with (motor stroke group) and without (control stroke group) motor impairment, and 2) to predict motor recovery through the relationship between local topological variations of the functional network and increased motor function. We modeled the brain's FC as a graph using fMRI data, and we characterized its interactions with the following graph metrics: degree, clustering coefficient, characteristic path length, and betweenness centrality (BC). For both patient groups, BC yielded the largest variations between the two analyzed time points, especially in the motor stroke group. This group presented significant correlations (P<0.05) between average BC changes and the improvements in upper-extremity Fugl-Meyer (UE-FM) scores at the primary sensorimotor cortex and the supplementary motor area for the CL hemisphere. These regions participate in processes related to the selection, planning, and execution of movement. Generally, higher increases in average BC over these areas were related to larger improvements in UE-FM assessment. Although the sample was small, these results suggest the possibility of using BC as an indication of brain plasticity mechanisms following stroke.

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