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1.
J Anim Ecol ; 93(6): 650-653, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38706185

RESUMO

Research Highlight: Mistrick, J., Veitch, J. S. M., Kitchen, S. M., Clague, S., Newman, B. C., Hall, R. J., Budischak, S. A., Forbes, K. M., & Craft, M. E. (2024). Effects of food supplementation and helminth removal on space use and spatial overlap in wild rodent populations. Journal of Animal Ecology. http://doi.org/10.1111/1365-2656.14067. The spread of pathogens has been of long-standing interest, even before dramatic outbreaks of avian influenza and the coronavirus pandemic spiked broad public interest. However, the dynamics of pathogen spread in wild populations are complex, with multiple effects shaping where animals go (their space use), population density and, more fundamentally, the resultant patterns of contacts (direct or indirect) among individuals. Thus, experimental studies exploring the dynamics of contact under different sets of conditions are needed. In the current field study, Mistrick et al. (2024) used a multifactorial experimental design, manipulating food availability and individual pathogen infection state in wild bank voles (Clethrionomys glareolus). They found that while food availability, individual traits and seasonality can affect how far individual voles moved, the degree of overlap between individual voles remained largely the same despite a high variation in population density-which itself was affected by food availability. These results highlight how biotic and abiotic factors can shape patterns of space use and balance the level of spatial overlap through multiple pathways.


Assuntos
Arvicolinae , Animais , Doenças dos Roedores/epidemiologia , Doenças dos Roedores/parasitologia , Doenças dos Roedores/virologia , Prevalência , Animais Selvagens , Masculino , Feminino
2.
J Anim Ecol ; 93(6): 743-754, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38415301

RESUMO

Animal space use and spatial overlap can have important consequences for population-level processes such as social interactions and pathogen transmission. Identifying how environmental variability and inter-individual variation affect spatial patterns and in turn influence interactions in animal populations is a priority for the study of animal behaviour and disease ecology. Environmental food availability and macroparasite infection are common drivers of variation, but there are few experimental studies investigating how they affect spatial patterns of wildlife. Bank voles (Clethrionomys glareolus) are a tractable study system to investigate spatial patterns of wildlife and are amenable to experimental manipulations. We conducted a replicated, factorial field experiment in which we provided supplementary food and removed helminths in vole populations in natural forest habitat and monitored vole space use and spatial overlap using capture-mark-recapture methods. Using network analysis, we quantified vole space use and spatial overlap. We compared the effects of food supplementation and helminth removal and investigated the impacts of season, sex and reproductive status on space use and spatial overlap. We found that food supplementation decreased vole space use while helminth removal increased space use. Space use also varied by sex, reproductive status and season. Spatial overlap was similar between treatments despite up to threefold differences in population size. By quantifying the spatial effects of food availability and macroparasite infection on wildlife populations, we demonstrate the potential for space use and population density to trade-off and maintain consistent spatial overlap in wildlife populations. This has important implications for spatial processes in wildlife including pathogen transmission.


Assuntos
Arvicolinae , Animais , Arvicolinae/fisiologia , Feminino , Masculino , Estações do Ano , Helmintíase Animal/parasitologia , Helmintíase Animal/epidemiologia , Doenças dos Roedores/parasitologia , Helmintos/fisiologia
3.
J Biomed Inform ; 157: 104714, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39187170

RESUMO

Autism spectrum disorder (ASD) is a common neurological condition. Early diagnosis and treatment are essential for enhancing the life quality of individuals with ASD. However, most existing studies either focus solely on the brain networks of subjects within a single atlas or merely employ simple matrix concatenation to represent the fusion of multi-atlas. These approaches neglected the natural spatial overlap that exists between brain regions across multi-atlas and did not fully capture the comprehensive information of brain regions under different atlases. To tackle this weakness, in this paper, we propose a novel multi-atlas fusion template based on spatial overlap degree of brain regions, which aims to obtain a comprehensive representation of brain networks. Specifically, we formally define a measurement of the spatial overlap among brain regions across different atlases, named spatial overlap degree. Then, we fuse the multi-atlas to obtain brain networks of each subject based on spatial overlap. Finally, the GCN is used to perform the final classification. The experimental results on Autism Brain Imaging Data Exchange (ABIDE) demonstrate that our proposed method achieved an accuracy of 0.757. Overall, our method outperforms SOTA methods in ASD/TC classification.


Assuntos
Transtorno do Espectro Autista , Encéfalo , Imageamento por Ressonância Magnética , Transtorno do Espectro Autista/diagnóstico , Humanos , Encéfalo/diagnóstico por imagem , Algoritmos , Neuroimagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Mapeamento Encefálico/métodos , Criança
4.
J Anim Ecol ; 89(1): 120-131, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30838656

RESUMO

The extent to which prey space use actively minimizes predation risk continues to ignite controversy. Methodological reasons that have hindered consensus include inconsistent measurements of predation risk, biased spatiotemporal scales at which responses are measured and lack of robust null expectations. We addressed all three challenges in a comprehensive analysis of the spatiotemporal responses of adult female elk (Cervus elaphus) to the risk of predation by wolves (Canis lupus) during winter in northern Yellowstone, USA. We quantified spatial overlap between the winter home ranges of GPS-collared elk and three measures of predation risk: the intensity of wolf space use, the distribution of wolf-killed elk and vegetation openness. We also assessed whether elk varied their use of areas characterized by more or less predation risk across hours of the day, and estimated encounter rates between simultaneous elk and wolf pack trajectories. We determined whether observed values were significantly lower than expected if elk movements were random with reference to predation risk using a null model approach. Although a small proportion of elk did show a tendency to minimize use of open vegetation at specific times of the day, overall we highlight a notable absence of spatiotemporal response by female elk to the risk of predation posed by wolves in northern Yellowstone. Our results suggest that predator-prey interactions may not always result in strong spatiotemporal patterns of avoidance.


Assuntos
Cervos , Lobos , Animais , Feminino , Movimento , Comportamento Predatório , Estações do Ano
5.
Nano Lett ; 19(1): 261-268, 2019 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-30540907

RESUMO

Controlling the nonlinear optical response of nanoscale metamaterials opens new exciting applications such as frequency conversion or flat metal optical elements. To utilize the already well-developed fabrication methods, a systematic design methodology for obtaining high nonlinearities is required. In this paper we consider an optimization-based approach, combining a multiparameter genetic algorithm with three-dimensional finite-difference time domain (FDTD) simulations. We investigate two choices of the optimization function: one which looks for plasmonic resonance enhancements at the frequencies of the process using linear FDTD, and another one, based on nonlinear FDTD, which directly computes the predicted nonlinear response. We optimize a four-wave-mixing process with specific predefined input frequencies in an array of rectangular nanocavities milled in a thin free-standing gold film. Both approaches yield a significant enhancement of the nonlinear signal. Although the direct calculation gives rise to the maximum possible signal, the linear optimization provides the expected triply resonant configuration with almost the same enhancement, while being much easier to implement in practice.

6.
J Synchrotron Radiat ; 26(Pt 3): 647-652, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31074427

RESUMO

A compact and robust diagnostic to determine spatial and temporal overlap between X-ray free-electron laser and optical laser pulses was developed and evaluated using monochromatic X-rays from the Linac Coherent Light Source. It was used to determine temporal overlap with a resolution of ∼10 fs, despite the large pulse energy fluctuations of the monochromatic X-ray pulses, and covers a wide optical wavelength range from ultraviolet to near-infrared with a single configuration.

7.
J Synchrotron Radiat ; 25(Pt 5): 1517-1528, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30179193

RESUMO

Extreme ultraviolet (XUV) and X-ray free-electron lasers enable new scientific opportunities. Their ultra-intense coherent femtosecond pulses give unprecedented access to the structure of undepositable nanoscale objects and to transient states of highly excited matter. In order to probe the ultrafast complex light-induced dynamics on the relevant time scales, the multi-purpose end-station CAMP at the free-electron laser FLASH has been complemented by the novel multilayer-mirror-based split-and-delay unit DESC (DElay Stage for CAMP) for time-resolved experiments. XUV double-pulses with delays adjustable from zero femtoseconds up to 650 picoseconds are generated by reflecting under near-normal incidence, exceeding the time range accessible with existing XUV split-and-delay units. Procedures to establish temporal and spatial overlap of the two pulses in CAMP are presented, with emphasis on the optimization of the spatial overlap at long time-delays via time-dependent features, for example in ion spectra of atomic clusters.

8.
Glob Chang Biol ; 24(1): 117-131, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28731569

RESUMO

Asymmetries in responses to climate change have the potential to alter important predator-prey interactions, in part by altering the location and size of spatial refugia for prey. We evaluated the effect of ocean warming on interactions between four important piscivores and four of their prey in the U.S. Northeast Shelf by examining species overlap under historical conditions (1968-2014) and with a doubling in CO2 . Because both predator and prey shift their distributions in response to changing ocean conditions, the net impact of warming or cooling on predator-prey interactions was not determined a priori from the range extent of either predator or prey alone. For Atlantic cod, an historically dominant piscivore in the region, we found that both historical and future warming led to a decline in the proportion of prey species' range it occupied and caused a potential reduction in its ability to exert top-down control on these prey. In contrast, the potential for overlap of spiny dogfish with prey species was enhanced by warming, expanding their importance as predators in this system. In sum, the decline in the ecological role for cod that began with overfishing in this ecosystem will likely be exacerbated by warming, but this loss may be counteracted by the rise in dominance of other piscivores with contrasting thermal preferences. Functional diversity in thermal affinity within the piscivore guild may therefore buffer against the impact of warming on marine ecosystems, suggesting a novel mechanism by which diversity confers resilience.


Assuntos
Mudança Climática , Peixes , Oceanos e Mares , Animais , Ecossistema , Comportamento Predatório/fisiologia
9.
J Anim Ecol ; 87(1): 274-284, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28940254

RESUMO

Rapid landscape alteration associated with human activity is currently challenging the evolved dynamical stability of many predator-prey systems by forcing species to behaviourally respond to novel environmental stimuli. In many forested systems, linear features (LFs) such as roads, pipelines and resource exploration lines (i.e. seismic lines) are a ubiquitous form of landscape alteration that have been implicated in altering predator-prey dynamics. One hypothesized effect is that LFs facilitate predator movement into and within prey refugia, thereby increasing predator-prey spatial overlap. We evaluated this hypothesis in a large mammal system, focusing on the interactions between boreal woodland caribou (Rangifer tarandus caribou) and their two main predators, wolves (Canis lupus) and black bears (Ursus americanus), during the calving season of caribou. In this system, LFs extend into and occur within peatlands (i.e. bogs and nutrient-poor fens), a habitat type highly used by caribou due to its refugia effects. Using resource selection analyses, we found that LFs increased predator selection of peatlands. Female caribou appeared to respond by avoiding LFs and areas with high LF density. However, in our study area, most caribou cannot completely avoid exposure to LFs and variation in female response had demographic effects. In particular, increasing proportional use of LFs by females negatively impacted survival of their neonate calves. Collectively, these results demonstrate how LFs can reduce the efficacy of prey refugia. Mitigating such effects will require limiting or restoring LFs within prey refugia, although the effectiveness of mitigation efforts will depend upon spatial scale, which in turn will be influenced by the life-history traits of predator and prey.


Assuntos
Ecossistema , Comportamento Predatório , Rena/fisiologia , Ursidae/fisiologia , Lobos/fisiologia , Animais , Animais Recém-Nascidos/fisiologia , Colúmbia Britânica , Meio Ambiente , Feminino , Dinâmica Populacional
10.
BMC Infect Dis ; 18(1): 598, 2018 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-30482166

RESUMO

BACKGROUND: In most developing economies particularly in Africa, more people are likely to die of HIV/AIDS and malaria compared to other diseases. HIV/AIDS tends to be superimposed on the long standing malaria burden particularly in sub-Saharan Africa. The detection and understanding of spatial overlaps in disease occurrence is important for integrated and targeted disease control. Integrated disease control can enhance efficiency and cost-effectiveness through the development of drugs targeting multiple infections in the same geographic space. METHODS: Using Zimbabwe as a case study, this study tests the hypothesis that malaria clusters coincide with HIV/AIDS clusters in space. Case data for the two diseases were obtained from the Ministry of Health and Child Care in Zimbabwe at district level via the District Health Information System (DHIS). Kulldorff's spatial scan statistic was used to test for spatial overlaps in clusters of high cases of HIV/AIDS and malaria at district level. The spatial scan test was used to identify areas with higher cases of HIV/AIDS and malaria than would be expected under spatial randomness. RESULTS: Results of this study indicate that primary clusters of HIV/AIDS and malaria were not spatially coincident in Zimbabwe. While no spatial overlaps were detected between primary clusters of the two diseases, spatial overlaps were detected among statistically significant secondary clusters of HIV/AIDS and malaria. Spatial overlaps between HIV/AIDS and malaria occurred in five districts in the northern and eastern regions of Zimbabwe. In addition, findings of this study indicate that HIV/AIDS is more widespread in Zimbabwe compared to malaria. CONCLUSIONS: The results of this study may therefore be used as a basis for spatially-targeted control of HIV/AIDS and malaria particularly in high disease burden areas. This is important as previous interventions have targeted the two diseases separately. Thus, targeted control could assist in resource allocation through prioritising areas in greatest need hence maximising the impact of disease control.


Assuntos
Síndrome da Imunodeficiência Adquirida/epidemiologia , Infecções por HIV/epidemiologia , Malária/epidemiologia , Adulto , Criança , Análise por Conglomerados , Coinfecção/epidemiologia , Atenção à Saúde , Demografia , Feminino , HIV , Humanos , Prevalência , Zimbábue/epidemiologia
11.
Oecologia ; 187(1): 15-23, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29616402

RESUMO

Home range, territory, and core areas are concepts that have been used to describe a species' space use. However, little research has been done to understand potential spatial relationships between them. While the relative importance of different areas of the home range has been addressed with utilization distributions, there is a lack of such analysis for territories. We mapped the locations of territorial advertisements (calls and drumming) of the pileated woodpecker in suburban areas to determine a more objective, behavior-based approach to define areas of importance within territories, which we called 'highly-defended areas'. We then analyzed the relationship between such highly-defended areas and a bird's home range and territory. On average, territories represented 69.6 ± 0.06% (mean ± SE) of a woodpecker's home range, and highly-defended areas were 34.3 ± 0.03% of their home range. Highly-defended areas objectively determined the portion of the territory that was important for fitness. For example, they contained a significant proportion of the nests and roost sites of pileated woodpeckers, which are important for reproduction and survivorship. This approach could be useful to further incorporate behavior in the study of the spatial ecology of species.


Assuntos
Aves , Comportamento de Retorno ao Território Vital , Animais , Ecologia , Comportamento Social , Territorialidade
12.
J Anim Ecol ; 86(5): 1054-1064, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28415134

RESUMO

Climate change is impacting different species at different rates, leading to alterations in biological interactions with ramifications for wider ecosystem functioning. Understanding these alterations can help improve predictive capacity and inform management efforts designed to mitigate against negative impacts. We investigated how the movement and space use patterns of polar bears (Ursus maritimus) in coastal areas in Svalbard, Norway, have been altered by a sudden decline in sea ice that occurred in 2006. We also investigated whether the spatial overlap between polar bears and their traditionally most important prey, ringed seals (Pusa hispida), has been affected by the sea-ice decline, as polar bears are dependent on a sea-ice platform for hunting seals. We attached biotelemetry devices to ringed seals (n = 60, both sexes) and polar bears (n = 67, all females) before (2002-2004) and after (2010-2013) a sudden decline in sea ice in Svalbard. We used linear mixed-effects models to evaluate the association of these species to environmental features and an approach based on Time Spent in Area to investigate changes in spatial overlap between the two species. Following the sea-ice reduction, polar bears spent the same amount of time close to tidal glacier fronts in the spring but less time in these areas during the summer and autumn. However, ringed seals did not alter their association with glacier fronts during summer, leading to a major decrease in spatial overlap values between these species in Svalbard's coastal areas. Polar bears now move greater distances daily and spend more time close to ground-nesting bird colonies, where bear predation can have substantial local effects. Our results indicate that sea-ice declines have impacted the degree of spatial overlap and hence the strength of the predator-prey relationship between polar bears and ringed seals, with consequences for the wider Arctic marine and terrestrial ecosystems. Shifts in ecological interactions are likely to become more widespread in many ecosystems as both predators and prey respond to changing environmental conditions induced by global warming, highlighting the importance of multi-species studies.


Assuntos
Mudança Climática , Focas Verdadeiras , Ursidae , Distribuição Animal , Animais , Regiões Árticas , Feminino , Masculino , Modelos Teóricos , Noruega , Dinâmica Populacional
13.
Alzheimers Dement ; 11(2): 161-74, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25617509

RESUMO

BACKGROUND: The use of hippocampal volumetry as a biomarker for Alzheimer's disease (AD) requires that tracers from different laboratories comply with the same segmentation method. Here we present a platform for training and qualifying new tracers to perform the manual segmentation of the hippocampus on magnetic resonance images (MRI) following the European Alzheimer's Disease Consortium and Alzheimer's Disease Neuroimaging Initiative (EADC-ADNI) Harmonized Protocol (HarP). Our objective was to demonstrate that the training process embedded in the platform leads to increased compliance and qualification with the HarP. METHOD: Thirteen new tracers' segmentations were compared with benchmark images with respect to: (a) absolute segmentation volume; (b) spatial overlap of contour with the reference using the Jaccard similarity index; and (c) spatial distance of contour with the reference. Point by point visual feedback was provided through three training phases on 10 MRI. Tracers were then tested on 10 different MRIs in the qualification phase. RESULTS: Statistical testing of training over three phases showed a significant increase of Jaccard (i.e. mean Jaccard overlap P < .001) between phases on average for all raters, demonstrating that training positively increased compliance with the HarP. Based on these results we defined qualification thresholds which all tracers were able to meet. CONCLUSIONS: This platform is an adequate infrastructure allowing standardized training and evaluation of tracers' compliance with the HarP. This is a necessary step allowing the use of hippocampal volumetry as a biomarker for AD in clinical and research centers.


Assuntos
Hipocampo/patologia , Processamento de Imagem Assistida por Computador/métodos , Capacitação em Serviço/métodos , Imageamento por Ressonância Magnética/métodos , Doença de Alzheimer/patologia , Disfunção Cognitiva/patologia , Hipocampo/anatomia & histologia , Humanos , Imageamento Tridimensional/métodos , Tamanho do Órgão , Reprodutibilidade dos Testes
14.
Sci Total Environ ; 913: 169712, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38160822

RESUMO

Spatial segregation of species along opposing resource gradients is a major research topic in ecology as it enables the coexistence and maintenance of high diversity. Thermocline stratification causes heterogeneous resource distribution, however, the effect of thermocline stratification on phytoplankton dynamic in-depth profiles is still unclear. To understand the underlying mechanism behind the effects of thermocline stratification on phytoplankton species diversity in stratified lakes, the monthly changes in thermocline parameters, deep chlorophyll maxima (DCM) parameters, spatial overlap (SO) among major phytoplankton taxonomic groups, and phytoplankton species diversity were evaluated in Lake Qiandaohu in the Zhejiang Province of China from April 2017 to December 2018. Thermocline depth (TD) was significantly negatively related to thermocline strength (TS). The monthly air temperature was the main driver behind the thermocline and the seasonal thermal-stratification cycle was divided into two stratification stages. Significant linear relationships were observed between the DCM parameters (depth, concentration, and thickness) and TD during the strong stratification period. TD was significantly positively related to phytoplankton species diversity and the SO between Cryptophyta and Chlorophyta as well as between Cryptophyta and Bacillariophyta during weak stratification periods. Significant positive correlations were observed between SO and Shannon diversity during both periods. Structural equation modeling (SEM) showed that air temperature significantly decreased TD and increased species diversity by increasing SO during the strong stratification period. Strong stratification under warming favored the formation of shallower and thinner DCMs, leading to phytoplankton coexistence and maintenance of high species diversity through a preclusion of dominance. This study characterized the temporal dynamics of phytoplankton dynamic in-depth profiles in response to strong stratification from warming.


Assuntos
Diatomáceas , Fitoplâncton , Estações do Ano , Clorofila , Ecologia , Lagos/química , China
15.
Mov Ecol ; 12(1): 58, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39215311

RESUMO

Direct encounters, in which two or more individuals are physically close to one another, are a topic of increasing interest as more and better movement data become available. Recent progress, including the development of statistical tools for estimating robust measures of changes in animals' space use over time, facilitates opportunities to link direct encounters between individuals with the long-term consequences of those encounters. Working with movement data for coyotes (Canis latrans) and grizzly bears (Ursus arctos horribilis), we investigate whether close intraspecific encounters were associated with spatial shifts in the animals' range distributions, as might be expected if one or both of the individuals involved in an encounter were seeking to reduce or avoid conflict over space. We analyze the movement data of a pair of coyotes in detail, identifying how a change in home range overlap resulting from altered movement behavior was apparently a consequence of a close intraspecific encounter. With grizzly bear movement data, we approach the problem as population-level hypothesis tests of the spatial consequences of encounters. We find support for the hypotheses that (1) close intraspecific encounters between bears are, under certain circumstances, associated with subsequent changes in overlap between range distributions and (2) encounters defined at finer spatial scales are followed by greater changes in space use. Our results suggest that animals can undertake long-term, large-scale spatial changes in response to close intraspecific encounters that have the potential for conflict. Overall, we find that analyses of movement data in a pairwise context can (1) identify distances at which individuals' proximity to one another may alter behavior and (2) facilitate testing of population-level hypotheses concerning the potential for direct encounters to alter individuals' space use.

16.
Ecol Evol ; 13(2): e9833, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36789348

RESUMO

Animals often occupy home ranges where they conduct daily activities. In many parrotfishes, large terminal phase (TP) males defend their diurnal (i.e., daytime) home ranges as intraspecific territories occupied by harems of initial phase (IP) females. However, we know relatively little about the exclusivity and spatial stability of these territories. We investigated diurnal home range behavior in several TPs and IPs of five common Caribbean parrotfish species on the fringing coral reefs of Bonaire, Caribbean Netherlands. We computed parrotfish home ranges to investigate differences in space use and then quantified spatial overlap of home ranges between spatially co-occurring TPs to investigate exclusivity. We also quantified the spatial overlap of home ranges estimated from repeat tracks of a few TPs to investigate their spatial stability. We then discussed these results in the context of parrotfish social behavior. Home range sizes differed significantly among species. Spatial overlap between home ranges was lower for intraspecific than interspecific pairs of TPs. Focal TPs frequently engaged in agonistic interactions with intraspecific parrotfish and interacted longest with intraspecific TP parrotfish. This behavior suggests that exclusionary agonistic interactions may contribute to the observed patterns of low spatial overlap between home ranges. The spatial overlap of home ranges estimated from repeated tracks of several TPs of three study species was high, suggesting that home ranges were spatially stable for at least 1 month. Taken together, our results provide strong evidence that daytime parrotfish space use is constrained within fixed intraspecific territories in which territory holders have nearly exclusive access to resources. Grazing by parrotfishes maintains benthic reef substrates in early successional states that are conducive to coral larval settlement and recruitment. Behavioral constraints on parrotfish space use may drive spatial heterogeneity in grazing pressure and affect local patterns of benthic community assembly. A thorough understanding of the spatial ecology of parrotfishes is, therefore, necessary to elucidate their functional roles on coral reefs.

17.
Brain Sci ; 14(1)2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38248255

RESUMO

Schizophrenia (SZ) is a complex psychiatric disorder with unclear etiology and pathological features. Neuroscientists are increasingly proposing that schizophrenia is an abnormality in the dynamic organization of brain networks. Previous studies have found that the dynamic brain networks of people with SZ are abnormal in both space and time. However, little is known about the interactions and overlaps between hubs of the brain underlying spatiotemporal dynamics. In this study, we aimed to investigate different patterns of spatial and temporal overlap of hubs between SZ patients and healthy individuals. Specifically, we obtained resting-state functional magnetic resonance imaging data from the public dataset for 43 SZ patients and 49 healthy individuals. We derived a representation of time-varying functional connectivity using the Jackknife Correlation (JC) method. We employed the Betweenness Centrality (BC) method to identify the hubs of the brain's functional connectivity network. We then applied measures of temporal overlap, spatial overlap, and hierarchical clustering to investigate differences in the organization of brain hubs between SZ patients and healthy controls. Our findings suggest significant differences between SZ patients and healthy controls at the whole-brain and subnetwork levels. Furthermore, spatial overlap and hierarchical clustering analysis showed that quasi-periodic patterns were disrupted in SZ patients. Analyses of temporal overlap revealed abnormal pairwise engagement preferences in the hubs of SZ patients. These results provide new insights into the dynamic characteristics of the network organization of the SZ brain.

18.
Vaccines (Basel) ; 11(4)2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37112714

RESUMO

The integration of immunization with other essential health services is among the strategic priorities of the Immunization Agenda 2030 and has the potential to improve the effectiveness, efficiency, and equity of health service delivery. This study aims to evaluate the degree of spatial overlap between the prevalence of children who have never received a dose of the diphtheria-tetanus-pertussis-containing vaccine (no-DTP) and other health-related indicators, to provide insight into the potential for joint geographic targeting of integrated service delivery efforts. Using geospatially modeled estimates of vaccine coverage and comparator indicators, we develop a framework to delineate and compare areas of high overlap across indicators, both within and between countries, and based upon both counts and prevalence. We derive summary metrics of spatial overlap to facilitate comparison between countries and indicators and over time. As an example, we apply this suite of analyses to five countries-Nigeria, Democratic Republic of the Congo (DRC), Indonesia, Ethiopia, and Angola-and five comparator indicators-children with stunting, under-5 mortality, children missing doses of oral rehydration therapy, prevalence of lymphatic filariasis, and insecticide-treated bed net coverage. Our results demonstrate substantial heterogeneity in the geographic overlap both within and between countries. These results provide a framework to assess the potential for joint geographic targeting of interventions, supporting efforts to ensure that all people, regardless of location, can benefit from vaccines and other essential health services.

19.
Animals (Basel) ; 13(13)2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37443923

RESUMO

Few studies test whether education can help increase support for wildlife management interventions. This mixed methods study sought to test the importance of educating a community on the use of a baboon-proof electric fence to mitigate negative interactions between humans and Chacma baboons (Papio ursinus) in a residential suburb of the City of Cape Town, South Africa. An educational video on the welfare, conservation and lifestyle benefits of a baboon-proof electric fence was included in a short online survey. The positioning of the video within the survey was randomised either to fall before or after questions probing the level of support for an electric fence. The results showed that watching the video before most survey questions increased the average marginal probability of supporting an electric fence by 15 percentage points. The study also explored whether the educational video could change people's minds. Those who saw the video towards the end of the survey were questioned again about the electric fence. Many changed their minds after watching the video, with support for the fence increasing from 36% to 50%. Of these respondents, the results show that being female raised the average marginal probability of someone changing their mind in favour of supporting the fence by 19%. Qualitative analysis revealed that support for or against the fence was multi-layered and that costs and concern for baboons were not the only relevant factors influencing people's choices. Conservation often needs to change people's behaviours. We need to know what interventions are effective. We show in the real world that an educational video can be effective and can moderately change people's opinions and that women are more likely to change their position in light of the facts than men. This study contributes to the emerging literature on the importance of education in managing conservation conflicts and the need for evidence-based interventions.

20.
J Alzheimers Dis ; 83(1): 305-317, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34308905

RESUMO

BACKGROUND: In vivo neuroimaging modalities such as magnetic resonance imaging (MRI), functional MRI (fMRI), magnetoencephalography (MEG), magnetic resonance spectroscopy (MRS), and quantitative susceptibility mapping (QSM) are useful techniques to understand brain anatomical structure, functional activity, source localization, neurochemical profiles, and tissue susceptibility respectively. Integrating unique and distinct information from these neuroimaging modalities will further help to enhance the understanding of complex neurological diseases. OBJECTIVE: To develop a processing scheme for multimodal data integration in a seamless manner on healthy young population, thus establishing a generalized framework for various clinical conditions (e.g., Alzheimer's disease). METHODS: A multimodal data integration scheme has been developed to integrate the outcomes from multiple neuroimaging data (fMRI, MEG, MRS, and QSM) spatially. Furthermore, the entire scheme has been incorporated into a user-friendly toolbox- "PRATEEK". RESULTS: The proposed methodology and toolbox has been tested for viability among fourteen healthy young participants. The data-integration scheme was tested for bilateral occipital cortices as the regions of interest and can also be extended to other anatomical regions. Overlap percentage from each combination of two modalities (fMRI-MRS, MEG-MRS, fMRI-QSM, and fMRI-MEG) has been computed and also been qualitatively assessed for combinations of the three (MEG-MRS-QSM) and four (fMRI-MEG-MRS-QSM) modalities. CONCLUSION: This user-friendly toolbox minimizes the need of an expertise in handling different neuroimaging tools for processing and analyzing multimodal data. The proposed scheme will be beneficial for clinical studies where geometric information plays a crucial role for advance brain research.


Assuntos
Pesquisa Biomédica , Encéfalo , Imagem Multimodal , Neuroimagem , Adulto , Feminino , Voluntários Saudáveis , Humanos , Processamento de Imagem Assistida por Computador , Masculino
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