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1.
J Neurosci ; 44(12)2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38388427

RESUMEN

Individual differences in cognitive performance in childhood are a key predictor of significant life outcomes such as educational attainment and mental health. Differences in cognitive ability are governed in part by variations in brain structure. However, studies commonly focus on either gray or white matter metrics in humans, leaving open the key question as to whether gray or white matter microstructure plays distinct or complementary roles supporting cognitive performance. To compare the role of gray and white matter in supporting cognitive performance, we used regularized structural equation models to predict cognitive performance with gray and white matter measures. Specifically, we compared how gray matter (volume, cortical thickness, and surface area) and white matter measures (volume, fractional anisotropy, and mean diffusivity) predicted individual differences in cognitive performance. The models were tested in 11,876 children (ABCD Study; 5,680 female, 6,196 male) at 10 years old. We found that gray and white matter metrics bring partly nonoverlapping information to predict cognitive performance. The models with only gray or white matter explained respectively 15.4 and 12.4% of the variance in cognitive performance, while the combined model explained 19.0%. Zooming in, we additionally found that different metrics within gray and white matter had different predictive power and that the tracts/regions that were most predictive of cognitive performance differed across metrics. These results show that studies focusing on a single metric in either gray or white matter to study the link between brain structure and cognitive performance are missing a key part of the equation.


Asunto(s)
Sustancia Blanca , Niño , Humanos , Masculino , Femenino , Sustancia Blanca/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Sustancia Gris/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética , Cognición
2.
J Allergy Clin Immunol ; 154(1): 131-142, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38670232

RESUMEN

BACKGROUND: Atopic dermatitis (AD) is the most common chronic inflammatory skin disease in both pediatric and adult populations. The development of AD has been linked to antibiotic usage, which causes perturbation of the microbiome and has been associated with abnormal immune system function. However, imbalances in the gut microbiome itself associated with antibiotic usage have been inconsistently linked to AD. OBJECTIVES: This study aimed to elucidate the timing and specific factors mediating the relationship between systemic (oral or intravenous) antibiotic usage and AD. METHODS: We used statistical modeling and differential analysis to link CHILD Cohort Study participants' history of antibiotic usage and early-life gut microbiome alterations to AD. RESULTS: Here we report that systemic antibiotics during the first year of life, as compared to later, are associated with AD risk (adjusted odds ratio [aOR] = 1.81; 95% CI: 1.28-2.57; P < .001), with an increased number of antibiotic courses corresponding to a dose response-like increased risk of AD risk (1 course: aOR: 1.67; 95% CI: 1.17-2.38; 2 or more courses: aOR: 2.16; 95% CI: 1.30-3.59). Further, we demonstrate that microbiome alterations associated with both AD and systemic antibiotic usage fully mediate the effect of antibiotic usage on the development of AD (ßindirect = 0.072; P < .001). Alterations in the 1-year infant gut microbiome of participants who would later develop AD included increased Tyzzerella nexilis, increased monosaccharide utilization, and parallel decreased Bifidobacterium and Eubacterium spp, and fermentative pathways. CONCLUSIONS: These findings indicate that early-life antibiotic usage, especially in the first year of life, modulates key gut microbiome components that may be used as markers to predict and possibly prevent the development of AD.


Asunto(s)
Antibacterianos , Dermatitis Atópica , Microbioma Gastrointestinal , Humanos , Dermatitis Atópica/microbiología , Dermatitis Atópica/inmunología , Microbioma Gastrointestinal/efectos de los fármacos , Lactante , Femenino , Masculino , Antibacterianos/efectos adversos , Recién Nacido , Estudios de Cohortes , Preescolar
3.
J Neurosci ; 43(19): 3557-3566, 2023 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-37028933

RESUMEN

Most prior research has focused on characterizing averages in cognition, brain characteristics, or behavior, and attempting to predict differences in these averages among individuals. However, this overwhelming focus on mean levels may leave us with an incomplete picture of what drives individual differences in behavioral phenotypes by ignoring the variability of behavior around an individual's mean. In particular, enhanced white matter (WM) structural microstructure has been hypothesized to support consistent behavioral performance by decreasing Gaussian noise in signal transfer. Conversely, lower indices of WM microstructure are associated with greater within-subject variance in the ability to deploy performance-related resources, especially in clinical populations. We tested a mechanistic account of the "neural noise" hypothesis in a large adult lifespan cohort (Cambridge Centre for Ageing and Neuroscience) with over 2500 adults (ages 18-102; 1508 female; 1173 male; 2681 behavioral sessions; 708 MRI scans) using WM fractional anisotropy to predict mean levels and variability in reaction time performance on a simple behavioral task using a dynamic structural equation model. By modeling robust and reliable individual differences in within-person variability, we found support for a neural noise hypothesis (Kail, 1997), with lower fractional anisotropy predicted individual differences in separable components of behavioral performance estimated using dynamic structural equation model, including slower mean responses and increased variability. These effects remained when including age, suggesting consistent effects of WM microstructure across the adult lifespan unique from concurrent effects of aging. Crucially, we show that variability can be reliably separated from mean performance using advanced modeling tools, enabling tests of distinct hypotheses for each component of performance.SIGNIFICANCE STATEMENT Human cognitive performance is defined not just by the long-run average, but trial-to-trial variability around that average. However, investigations of cognitive abilities and changes during aging have largely ignored this variability component of behavior. We provide evidence that white matter (WM) microstructure predicts individual differences in mean performance and variability in a sample spanning the adult lifespan (18-102). Unlike prior studies of cognitive performance and variability, we modeled variability directly and distinct from mean performance using a dynamic structural equation model, which allows us to decouple variability from mean performance and other complex features of performance (e.g., autoregression). The effects of WM were robust above the effect of age, highlighting the role of WM in promoting fast and consistent performance.


Asunto(s)
Sustancia Blanca , Adulto , Humanos , Masculino , Femenino , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/fisiología , Longevidad , Tiempo de Reacción/fisiología , Imagen de Difusión Tensora , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Cognición/fisiología , Envejecimiento/fisiología
4.
Genet Epidemiol ; 47(8): 585-599, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37573486

RESUMEN

We propose structural equation models (SEMs) as a general framework to infer causal networks for metabolites and other complex traits. Traditionally SEMs are used only for individual-level data under the assumption that all instrumental variables (IVs) are valid. To overcome these limitations, we propose both one- and two-sample approaches for causal network inference based on SEMs that can: (1) perform causal analysis and discover causal relationships among multiple traits; (2) account for the possible presence of some invalid IVs; (3) allow for data analysis using only genome-wide association studies (GWAS) summary statistics when individual-level data are not available; (4) consider the possibility of bidirectional relationships between traits. Our method employs a simple stepwise selection to identify invalid IVs, thus avoiding false positives while possibly increasing true discoveries based on two-stage least squares (2SLS). We use both real GWAS data and simulated data to demonstrate the superior performance of our method over the standard 2SLS/SEMs. For real data analysis, our proposed approach is applied to a human blood metabolite GWAS summary data set to uncover putative causal relationships among the metabolites; we also identify some metabolites (putative) causal to Alzheimer's disease (AD), which, along with the inferred causal metabolite network, suggest some possible pathways of metabolites involved in AD.


Asunto(s)
Enfermedad de Alzheimer , Estudio de Asociación del Genoma Completo , Humanos , Estudio de Asociación del Genoma Completo/métodos , Modelos Genéticos , Fenotipo , Enfermedad de Alzheimer/genética
5.
Cancer ; 2024 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-39097814

RESUMEN

BACKGROUND: Social isolation and social connectedness are health determinants and aspects of social well-being with strong associations with psychological distress. This study evaluated relationships among social isolation, social connectedness, and psychological distress (i.e., depression, anxiety) over 1 year in young adult (YA) cancer survivors 18-39 years old. METHODS: Participants were YAs in a large cohort study that completed questionnaires every 2 months for 1 year. Social isolation, aspects of social connectedness (i.e., companionship, emotional support, instrumental support, and informational support), depression, and anxiety were assessed with Patient-Reported Outcomes Measurement Information System short form measures. Mixed-effect models were used to evaluate changes over time. Confirmatory factor analysis and multilevel structural equation modeling were used to define social connectedness as a latent construct and determine whether relationships between social isolation and psychological distress were mediated by social connectedness. RESULTS: Participants (N = 304) were mean (M) = 33.5 years old (SD = 4.7) and M = 4.5 years (SD = 3.5) post-initial cancer diagnosis. Most participants were female (67.4%) and non-Hispanic White (68.4%). Average scores for social well-being and psychological distress were within normative ranges and did not change (p values >.05). However, large proportions of participants reported at least mild social isolation (27%-30%), depressive symptoms (36%-37%), and symptoms of anxiety (49%-51%) at each time point. Across participants, more social isolation was related to less social connectedness (p values <.001), more depressive symptoms (p < .001), and more symptoms of anxiety (p < .001). Social connectedness mediated the relationship between social isolation and depression (p = .004), but not anxiety (p > .05). CONCLUSIONS: Social isolation and connectedness could be intervention targets for reducing depression among YA cancer survivors.

6.
BMC Plant Biol ; 24(1): 43, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38200422

RESUMEN

BACKGROUND: The development of the plant in vitro techniques has brought about the variation identified in regenerants known as somaclonal or tissue culture-induced variation (TCIV). S-adenosyl-L-methionine (SAM), glutathione (GSH), low methylated pectins (LMP), and Cu(II) ions may be implicated in green plant regeneration efficiency (GPRE) and TCIV, according to studies in barley (Hordeum vulgare L.) and partially in triticale (× Triticosecale spp. Wittmack ex A. Camus 1927). Using structural equation models (SEM), these metabolites have been connected to the metabolic pathways (Krebs and Yang cycles, glycolysis, transsulfuration), but not for triticale. Using metabolomic and (epi)genetic data, the study sought to develop a triticale regeneration efficiency statistical model. The culture's induction medium was supplemented with various quantities of Cu(II) and Ag(I) ions for regeneration. The period of plant regeneration has also changed. The donor plant, anther-derived regenerants, and metAFLP were utilized to analyze TCIV concerning DNA in symmetric (CG, CHG) and asymmetric (CHH) sequence contexts. Attenuated Total Reflectance-Fourier Transfer Infrared (ATR-FTIR) spectroscopy was used to gather the metabolomic information on LMP, SAM, and GSH. To frame the data, a structural equation model was employed. RESULTS: According to metAFLP analysis, the average sequence change in the CHH context was 8.65%, and 0.58% was de novo methylation. Absorbances of FTIR spectra in regions specific for LMP, SAM, and GSH were used as variables values introduced to the SEM model. The average number of green regenerants per 100 plated anthers was 2.55. CONCLUSIONS: The amounts of pectin demethylation, SAM, de novo methylation, and GSH are connected in the model to explain GPRE. By altering the concentration of Cu(II) ions in the medium, which influences the amount of pectin, triticale's GPRE can be increased.


Asunto(s)
Hordeum , Triticale , Suplementos Dietéticos , Glutatión , Hordeum/genética , Pectinas , Iones
7.
Metabolomics ; 20(4): 71, 2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38972029

RESUMEN

BACKGROUND AND OBJECTIVE: Blood-based small molecule metabolites offer easy accessibility and hold significant potential for insights into health processes, the impact of lifestyle, and genetic variation on disease, enabling precise risk prevention. In a prospective study with records of heart failure (HF) incidence, we present metabolite profiling data from individuals without HF at baseline. METHODS: We uncovered the interconnectivity of metabolites using data-driven and causal networks augmented with polygenic factors. Exploring the networks, we identified metabolite broadcasters, receivers, mediators, and subnetworks corresponding to functional classes of metabolites, and provided insights into the link between metabolomic architecture and regulation in health. We incorporated the network structure into the identification of metabolites associated with HF to control the effect of confounding metabolites. RESULTS: We identified metabolites associated with higher and lower risk of HF incidence, such as glycine, ureidopropionic and glycocholic acids, and LPC 18:2. These associations were not confounded by the other metabolites due to uncovering the connectivity among metabolites and adjusting each association for the confounding metabolites. Examples of our findings include the direct influence of asparagine on glycine, both of which were inversely associated with HF. These two metabolites were influenced by polygenic factors and only essential amino acids, which are not synthesized in the human body and are obtained directly from the diet. CONCLUSION: Metabolites may play a critical role in linking genetic background and lifestyle factors to HF incidence. Revealing the underlying connectivity of metabolites associated with HF strengthens the findings and facilitates studying complex conditions like HF.


Asunto(s)
Insuficiencia Cardíaca , Metabolómica , Insuficiencia Cardíaca/metabolismo , Humanos , Metabolómica/métodos , Masculino , Femenino , Estudios Prospectivos , Persona de Mediana Edad , Metaboloma , Anciano , Redes y Vías Metabólicas
8.
Respir Res ; 25(1): 306, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39135076

RESUMEN

BACKGROUND: Small airway dysfunction not only affects asthma control, but also has adverse effects on the psychological and/or social activities of asthma patients. However, few long-term observational studies have explored the complex relationship between small airway dysfunction and asthma control and health-related quality of life in patients with asthma exacerbations. METHODS: The study recruited 223 patients with exacerbations of asthma (i.e. those with at least one asthma attack over the past year) and 228 patients without exacerbations of asthma (i.e. those without asthma attacks over the past year). We evaluated SAD in patients with asthma exacerbations using impulse oscillometry method. At each evaluation time point within one year of follow-up, the attending physician conducts a case investigation of the patients. We analyzed the correlation between SAD and general characteristics (age, obesity, smoking history), type 2 inflammation (blood eosinophils, exhaled nitric oxide), FEV1, as well as asthma control (ACT) and health-related quality of life (mini-AQLQ) in patients with asthma exacerbations, and constructed a structural equation model to evaluate the causality of these clinical variables. RESULTS: The SAD prevalence in patients with asthma exacerbation is as high as 75%. SAD is connected with poor asthma control and poor health-related quality of life. The structural equation model indicates that age, obesity, FeNO, and FEV1 are independent predictive factors of SAD. SAD is the main determinant factor of asthma control, which in turn affected health-related quality of life. FEV1 and age directly affect asthma control and affect health-related quality of life through asthma control. In addition, there is a bidirectional relationship between FEV1 and small airway dysfunction and between asthma control and health-related quality of life. CONCLUSIONS: Small airways are involved from an early stage in asthma. Abnormal function of the small airways can significantly increase airway resistance in asthma patients, while worsening their clinical symptoms. In addition, aging is also a key risk factor for asthma control. Especially, small airway dysfunction links asthma control with health-related quality of life.


Asunto(s)
Asma , Calidad de Vida , Humanos , Asma/epidemiología , Asma/fisiopatología , Asma/diagnóstico , Asma/psicología , Femenino , Masculino , Persona de Mediana Edad , Adulto , Progresión de la Enfermedad , Anciano , Estudios de Seguimiento
9.
Psychol Med ; : 1-11, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39228209

RESUMEN

BACKGROUND: Different aspects of social relationships (e.g., social network size or loneliness) have been associated with dementia risk, while their overlap and potentially underlying pathways remain largely unexplored. This study therefore aimed to (1) discriminate between different facets of social relationships by means of factor analysis, (2) examine their associations with dementia risk, and (3) assess mediation by depressive symptoms. METHODS: Thirty-six items from questionnaires on social relationships administered in Wave 2 (2004/2005) of the English Longitudinal Study of Ageing (n = 7536) were used for exploratory and confirmatory factor analysis. Factors were then used as predictors in Cox proportional hazard models with dementia until Wave 9 as outcome, adjusted for demographics and cardiovascular risk factors. Structural equation modeling tested mediation by depressive symptoms through effect decomposition. RESULTS: Factor analyses identified six social factors. Across a median follow-up time of 11.8 years (IQR = 5.9-13.9 years), 501 people developed dementia. Higher factor scores for frequency and quality of contact with children (HR = 0.88; p = 0.021) and more frequent social activity engagement (HR = 0.84; p < 0.001) were associated with lower dementia risk. Likewise, higher factor scores for loneliness (HR = 1.13; p = 0.011) and negative experiences of social support (HR = 1.10; p = 0.047) were associated with higher dementia risk. Mediation analyses showed a significant partial effect mediation by depressive symptoms for all four factors. Additional analyses provided little evidence for reverse causation. CONCLUSIONS: Frequency and quality of social contacts, social activity engagement, and feelings of loneliness are associated with dementia risk and might be suitable targets for dementia prevention programs, partly by lowering depressive symptoms.

10.
Behav Genet ; 54(2): 151-168, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38108996

RESUMEN

Contemporary genome-wide association study (GWAS) methods typically do not account for variability in genetic effects throughout development. We applied genomic structural equation modeling to combine developmentally-informative phenotype data and GWAS to create polygenic scores (PGS) for alcohol use frequency that are specific to developmental stage. Longitudinal cohort studies targeted for gene-identification analyses include the Collaborative Study on the Genetics of Alcoholism (adolescence n = 1,118, early adulthood n = 2,762, adulthood n = 5,255), the National Longitudinal Study of Adolescent to Adult Health (adolescence n = 3,089, early adulthood n = 3,993, adulthood n = 5,149), and the Avon Longitudinal Study of Parents and Children (ALSPAC; adolescence n = 5,382, early adulthood n = 3,613). PGS validation analyses were conducted in the COGA sample using an alternate version of the discovery analysis with COGA removed. Results suggest that genetic liability for alcohol use frequency in adolescence may be distinct from genetic liability for alcohol use frequency later in developmental periods. The age-specific PGS predicts an increase of 4 drinking days per year per PGS standard deviation when modeled separately from the common factor PGS in adulthood. The current work was underpowered at all steps of the analysis plan. Though small sample sizes and low statistical power limit the substantive conclusions that can be drawn regarding these research questions, this work provides a foundation for future genetic studies of developmental variability in the genetic underpinnings of alcohol use behaviors and genetically-informed, age-matched phenotype prediction.


Asunto(s)
Alcoholismo , Estudio de Asociación del Genoma Completo , Adulto , Adolescente , Niño , Humanos , Recién Nacido , Estudios Longitudinales , Alcoholismo/genética , Consumo de Bebidas Alcohólicas/genética , Estudios de Cohortes
11.
Cogn Neuropsychol ; : 1-16, 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38970815

RESUMEN

The exploration of naming error patterns in aphasia provides insights into the cognitive processes underlying naming performance. We investigated how semantic and phonological abilities correlate and how they influence naming performance in aphasia. Data from 296 individuals with aphasia, drawn from the Moss Aphasia Psycholinguistics Project Database, were analyzed using a structural equation model. The model incorporated latent variables for semantics and phonology and manifest variables for naming accuracy and error patterns. There was a moderate positive correlation between semantics and phonology after controlling for overall aphasia severity. Both semantic and phonological abilities influenced naming accuracy. Semantic abilities negatively related to semantic, mixed, unrelated errors, and no responses. Interestingly, phonology positively affected semantic errors. Additionally, phonological abilities negatively related to each of phonological and neologism errors. These results highlight the role of semantic and phonological skills on naming performance in aphasia and reveal a relationship between these cognitive processes.

12.
Ecol Appl ; 34(6): e3004, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38925578

RESUMEN

Compound effects of anthropogenic disturbances on wildlife emerge through a complex network of direct responses and species interactions. Land-use changes driven by energy and forestry industries are known to disrupt predator-prey dynamics in boreal ecosystems, yet how these disturbance effects propagate across mammal communities remains uncertain. Using structural equation modeling, we tested disturbance-mediated pathways governing the spatial structure of multipredator multiprey boreal mammal networks across a landscape-scale disturbance gradient within Canada's Athabasca oil sands region. Linear disturbances had pervasive direct effects, increasing site use for all focal species, except black bears and threatened caribou, in at least one landscape. Conversely, block (polygonal) disturbance effects were negative but less common. Indirect disturbance effects were widespread and mediated by caribou avoidance of wolves, tracking of primary prey by subordinate predators, and intraguild dependencies among predators and large prey. Context-dependent responses to linear disturbances were most common among prey and within the landscape with intermediate disturbance. Our research suggests that industrial disturbances directly affect a suite of boreal mammals by altering forage availability and movement, leading to indirect effects across a range of interacting predators and prey, including the keystone snowshoe hare. The complexity of network-level direct and indirect disturbance effects reinforces calls for increased investment in addressing habitat degradation as the root cause of threatened species declines and broader ecosystem change.


Asunto(s)
Mamíferos , Animales , Mamíferos/fisiología , Modelos Biológicos , Ecosistema
13.
Am J Bot ; 111(5): e16349, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38783552

RESUMEN

PREMISE: Leaf tensile resistance, a leaf's ability to withstand pulling forces, is an important determinant of plant ecological strategies. One potential driver of leaf tensile resistance is growing season length. When growing seasons are long, strong leaves, which often require more time and resources to construct than weak leaves, may be more advantageous than when growing seasons are short. Growing season length and other ecological conditions may also impact the morphological traits that underlie leaf tensile resistance. METHODS: To understand variation in leaf tensile resistance, we measured size-dependent leaf strength and size-independent leaf toughness in diverse genotypes of the widespread perennial grass Panicum virgatum (switchgrass) in a common garden. We then used quantitative genetic approaches to estimate the heritability of leaf tensile resistance and whether there were genetic correlations between leaf tensile resistance and other morphological traits. RESULTS: Leaf tensile resistance was positively associated with aboveground biomass (a proxy for fitness). Moreover, both measures of leaf tensile resistance exhibited high heritability and were positively genetically correlated with leaf lamina thickness and leaf mass per area (LMA). Leaf tensile resistance also increased with the growing season length in the habitat of origin, and this effect was mediated by both LMA and leaf thickness. CONCLUSIONS: Differences in growing season length may promote selection for different leaf lifespans and may explain existing variation in leaf tensile resistance in P. virgatum. In addition, the high heritability of leaf tensile resistance suggests that P. virgatum will be able to respond to climate change as growing seasons lengthen.


Asunto(s)
Hojas de la Planta , Estaciones del Año , Hojas de la Planta/anatomía & histología , Hojas de la Planta/genética , Hojas de la Planta/fisiología , Hojas de la Planta/crecimiento & desarrollo , Panicum/genética , Panicum/fisiología , Panicum/anatomía & histología , Panicum/crecimiento & desarrollo , Resistencia a la Tracción , Biomasa , Fenotipo , Genotipo , Carácter Cuantitativo Heredable
14.
Conserv Biol ; : e14364, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39225252

RESUMEN

Anthropogenic activities may alter felid assemblage structure, facilitating the persistence of tolerant species (commonly mesopredators), excluding ecologically demanding ones (top predators) and, consequently, changing coexistence rules. We aimed to determine how human activities influence intraguild relationships among top predators and their cascading effects on mesopredators, which remain poorly understood despite evidence of top carnivore decline. We used structural equation modeling at a continental scale to investigate how habitat quality and quantity, livestock density, and other human pressures modified the intraguild relations of the 3 species that are at the top of the food chain in the Neotropics: jaguars (Panthera onca), pumas (Puma concolor), and ocelots (Leopardus pardalis). We included presence-absence data derived from systematic studies compiled in Neocarnivores data set for these felid species at 0.0833° resolution. Human disturbance reduced the probability of jaguar occurrence by -0.35 standard deviations. Unexpectedly, the presence of sheep (Ovis aries) or goats (Capra aegagrus hircus) and jaguars was positively related to the presence of pumas, whereas puma presence was negatively related to the presence of ocelots. Extent of forest cover had more of an effect on jaguar (ß = 0.23) and ocelot (ß = 0.12) occurrences than the extent of protected area, which did not have a significant effect. The lack of effect of human activities on puma presence and the positive effect of small livestock supports the notion that pumas are more adaptable to habitat disturbance than jaguars. Our findings suggest that human disturbance has the potential to reverse the hierarchical competition dominance among large felids, leading to an unbalanced community structure. This shift disadvantages jaguars and elevates the position of pumas in the assemblage hierarchy, resulting in the exclusion of ocelots, despite their relatively lower susceptibility to anthropogenic disturbance. Our results suggest that conservation efforts should extend beyond protected areas to encompass the surrounding landscape, where complexities and potential conflicts are more pronounced.


Efectos de la tolerancia dispareja a las perturbaciones humanas sobre las interacciones de dominancia de los depredadores mayores Resumen Las actividades antropogénicas pueden alterar la estructura de las poblaciones de félidos, lo que facilita la persistencia de especies tolerantes (normalmente mesodepredadores), excluye a otras especies con exigencias ecológicas (depredadores mayores) y, en consecuencia, modifica las reglas de coexistencia. Buscamos determinar cómo influyen las actividades humanas sobre las relaciones entre gremios de los depredadores superiores y sus efectos en cascada sobre los mesodepredadores, que aún son poco conocidos a pesar de las pruebas del declive de los carnívoros superiores. Utilizamos modelos de ecuaciones estructurales a escala continental para investigar cómo la calidad y cantidad del hábitat, la densidad ganadera y otras presiones humanas modifican las relaciones entre gremios de las tres especies que se encuentran en la cima de la cadena trófica en el Neotrópico: jaguares (Panthera onca), pumas (Puma concolor) y ocelotes (Leopardus pardalis). Incluimos datos de presencia­ausencia derivados de estudios sistemáticos recopilados en el conjunto de datos Neocarnivores para estas especies de félidos con una resolución de 0.0833°. Las perturbaciones humanas redujeron la probabilidad de aparición del jaguar en ­0.35 desviaciones estándar. De forma inesperada, la presencia de ovejas (Ovis aries) o cabras (Capra aegargrus hircus) y jaguares tuvo una relación positiva con la presencia de pumas, mientras que la presencia de pumas tuvo una relación negativa con la presencia de ocelotes. La extensión de la cubierta forestal tuvo más efecto sobre la presencia de jaguares (ß = 0.23) y ocelotes (ß = 0.12) que la extensión del área protegida, que no tuvo un efecto significativo. La falta de efectos de las actividades humanas sobre la presencia del puma y el efecto positivo del ganado menor apoyan la idea de que los pumas son más adaptables a las perturbaciones del hábitat que los jaguares. Nuestros hallazgos sugieren que las perturbaciones humanas tienen el potencial de invertir la dominancia jerárquica de competencia entre los grandes félidos, lo que lleva a una estructura comunitaria desequilibrada. Este cambio perjudica a los jaguares y eleva la posición de los pumas en la jerarquía del ensamblaje, lo que excluye a los ocelotes, a pesar de su relativamente menor susceptibilidad a las perturbaciones antropogénicas. Nuestros resultados sugieren que los esfuerzos de conservación deberían extenderse más allá de las áreas protegidas para abarcar el paisaje circundante, donde las complejidades y los conflictos potenciales son más pronunciados.

15.
BMC Infect Dis ; 24(1): 642, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38926657

RESUMEN

OBJECTIVE: Given the high prevalence of hypertension among Chinese adults, this population is at a significantly increased risk of severe COVID-19 complications. The purpose of this study is to assess the willingness of Chinese hypertensive adults to receive the COVID-19 vaccine and to identify the diverse factors that shape their vaccination decisions. METHODS: Sampling was conducted utilizing multistage stratified random sampling, and ultimately, a total of 886 adult hypertensive patients from Luzhou City in Southwest China were included in this study. The questionnaire design was based on the Theory of Planned Behaviour and was used to investigate their willingness to be vaccinated with COVID-19. Structural equation modeling was employed for data analysis. RESULTS: The results showed that 75.6% of hypertensive individuals were willing to receive COVID-19 vaccination. The structural equation modeling revealed that Subjective Norms (path coefficient = 0.361, CR = 8.049, P < 0.001) and Attitudes (path coefficient = 0.253, CR = 4.447, P < 0.001) had positive effects on vaccination willingness, while Perceived Behavioral Control (path coefficient=-0.004, CR=-0.127, P = 0.899) had no significant impact on Behavioral Attitudes. Mediation analysis indicated that Knowledge (indirect path coefficient = 0.032, LLCI = 0.014, ULCI = 0.058), Risk Perception (indirect path coefficient = 0.077, LLCI = 0.038, ULCI = 0.124), and Subjective Norms (indirect path coefficient = 0.044, LLCI = 0.019, ULCI = 0.087) significantly influenced vaccination willingness through Attitudes as a mediating factor. CONCLUSION: The willingness of hypertensive individuals to receive the COVID-19 vaccination is not satisfactory. The Theory of Planned Behavior provides valuable insights into understanding their vaccination intentions. Efforts should be concentrated on enhancing the subjective norms, attitudes, and knowledge about vaccination of hypertensive patients.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Hipertensión , Intención , SARS-CoV-2 , Vacunación , Humanos , Hipertensión/epidemiología , Hipertensión/psicología , COVID-19/prevención & control , COVID-19/epidemiología , COVID-19/psicología , Masculino , Femenino , China/epidemiología , Persona de Mediana Edad , Vacunas contra la COVID-19/administración & dosificación , Vacunación/psicología , Vacunación/estadística & datos numéricos , Adulto , Encuestas y Cuestionarios , Análisis de Clases Latentes , Anciano , Conocimientos, Actitudes y Práctica en Salud , Aceptación de la Atención de Salud/psicología , Aceptación de la Atención de Salud/estadística & datos numéricos , Estudios Transversales , Pueblos del Este de Asia
16.
BMC Infect Dis ; 24(1): 788, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39107716

RESUMEN

INTRODUCTION: Despite COVID-19 being highly contagious and spreading to several countries, the university community has overlooked prevention measures. For more than five decades, the Health Belief Model (HBM) has been a widely used conceptual framework in health behavior. structural equation modeling(SEM) analysis is an advanced statistical method capable of rectifying failures of the basic models and showing complex relations Thus this study aimed to determine the magnitude of COVID-19 prevention behavior and identify its associated factors using HBM and SEM analysis. METHOD: An institutional-based cross-sectional study was conducted among academic staff of the University of Gondar in Ethiopia from April 10 to May 10/2021. Daniel Soper's sample size calculator was used to determine the sample size. Proportional allocation to each campus followed by a simple random sampling technique was employed to select study subjects. A pre-tested, structured questionnaire was used to collect the data. Structural equation modeling analysis was employed to show the relationship between health belief model constructs and their effect on preventive behavior. RESULT: A total of 602 academic staff participated. The magnitude of good COVID-19 preventive behavior was 24.8%. The HBM explained 55% of the variance in preventive behavior. Perceived barriers (ß = -0.37, p < 0.05), self-efficacy (ß = 0.32, p < 0.05), perceived susceptibility (ß = 0.23, p < 0.05), and perceived benefit (ß = 0.16, p < 0.05) were the direct significant predictors of COVID 19 prevention behavior. CONCLUSION: only a quarter of the academic staff have good COVID-19 preventive behavior. The HBM explained a great amount of variance in preventive behavior and Perceived barriers, benefits, susceptibility, and self-efficacy significantly associated with prevention behavior. Carefully planned intervention that considers those significant perceptions should be designed and implemented to raise COVID-19 prevention behavior.


Asunto(s)
COVID-19 , Conductas Relacionadas con la Salud , Modelo de Creencias sobre la Salud , SARS-CoV-2 , Humanos , COVID-19/prevención & control , COVID-19/epidemiología , COVID-19/psicología , Estudios Transversales , Masculino , Femenino , Adulto , Etiopía/epidemiología , Encuestas y Cuestionarios , Análisis de Clases Latentes , Universidades , Conocimientos, Actitudes y Práctica en Salud , Persona de Mediana Edad , Adulto Joven , Autoeficacia
17.
Environ Sci Technol ; 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39134052

RESUMEN

Methane fluxes (FCH4) vary significantly across wetland ecosystems due to complex mechanisms, challenging accurate estimations. The interactions among environmental drivers, while crucial in regulating FCH4, have not been well understood. Here, the interactive effects of six environmental drivers on FCH4 were first analyzed using 396,322 half-hourly measurements from 22 sites across various wetland types and climate zones. Results reveal that soil temperature, latent heat turbulent flux, and ecosystem respiration primarily exerted direct effects on FCH4, while air temperature and gross primary productivity mainly exerted indirect effects by interacting with other drivers. Significant spatial variability in FCH4 regulatory mechanisms was highlighted, with different drivers demonstrated varying direct, indirect, and total effects among sites. This spatial variability was then linked to site-specific annual-average air temperature (17.7%) and water table (9.0%) conditions, allowing the categorization of CH4 sources into four groups with identified critical drivers. An improved estimation approach using a random forest model with three critical drivers was consequently proposed, offering accurate FCH4 predictions with fewer input requirements. By explicitly accounting for environmental interactions and interpreting spatial variability, this study enhances our understanding of the mechanisms regulating CH4 emissions, contributing to more efficient modeling and estimation of wetland FCH4.

18.
Dev Sci ; 27(5): e13519, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38679927

RESUMEN

The present longitudinal study investigated the hypothesis that early musical skills (as measured by melodic and rhythmic perception and memory) predict later literacy development via a mediating effect of phonology. We examined 130 French-speaking children, 31 of whom with a familial risk for developmental dyslexia (DD). Their abilities in the three domains were assessed longitudinally with a comprehensive battery of behavioral tests in kindergarten, first grade, and second grade. Using a structural equation modeling approach, we examined potential longitudinal effects from music to literacy via phonology. We then investigated how familial risk for DD may influence these relationships by testing whether atypical music processing is a risk factor for DD. Results showed that children with a familial risk for DD consistently underperformed children without familial risk in music, phonology, and literacy. A small effect of musical ability on literacy via phonology was observed, but may have been induced by differences in stability across domains over time. Furthermore, early musical skills did not add significant predictive power to later literacy difficulties beyond phonological skills and family risk status. These findings are consistent with the idea that certain key auditory skills are shared between music and speech processing, and between DD and congenital amusia. However, they do not support the notion that music perception and memory skills can serve as a reliable early marker of DD, nor as a valuable target for reading remediation. RESEARCH HIGHLIGHTS: Music, phonology, and literacy skills of 130 children, 31 of whom with a familial risk for dyslexia, were examined longitudinally. Children with a familial risk for dyslexia consistently underperformed children without familial risk in musical, phonological, and literacy skills. Structural equation models showed a small effect of musical ability in kindergarten on literacy in second grade, via phonology in first grade. However, early musical skills did not add significant predictive power to later literacy difficulties beyond phonological skills and family risk status.


Asunto(s)
Dislexia , Música , Humanos , Dislexia/genética , Dislexia/fisiopatología , Estudios Longitudinales , Niño , Masculino , Femenino , Factores de Riesgo , Lectura , Preescolar , Percepción Auditiva/fisiología
19.
BMC Endocr Disord ; 24(1): 75, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38807076

RESUMEN

BACKGROUND: Metabolic syndrome (MetS) is associated to sleep duration. It is crucial to identify factors that disrupt sleep regulation. The study aimed to assess the indirect effect of risk factors related to MetS severity through sleep duration by utilizing a structural equation model (SEM). METHODS: The study involving 3,935 adults from the baseline data of the Ravansar Non-Communicable Disease (RaNCD) cohort study. MetS severity scores were the outcome variables. SEM was employed to explore the relationships, utilizing IBM SPSS and AMOS version 23. RESULTS: The mean MetS severity score was higher in women compared to men (0.25 vs. 0.16, P = 0.003). In men, socioeconomic status (SES) has a positive direct effect (ß = 0.048) and a negative indirect effect (ß=-0.006) on MetS severity. Increased physical activity is directly (ß=-0.036) and indirectly (ß=-0.093) associated with reducing MetS severity. Nap duration is directly linked to an increase (ß = 0.072) but has an indirect effect (ß=-0.008) in decreasing MetS severity. In women, SES has a direct (ß=-0.020) and indirect (ß=-0.001) inverse relationship with MetS severity. Increased physical activity is directly (ß=-0.048) and indirectly (ß=-0.036) associated with decreasing MetS severity in women. Nap duration is directly associated with an increase in MetS severity (ß=-0.018) but indirectly contributes to its reduction (ß=-0.002). Sleep duration not only directly affects MetS severity but is also influenced by age, SES, physical activity, obesity and nap duration. CONCLUSION: Physical activity, SES, and nap duration directly and indirectly effect the MetS severity. Sleep duration was recognized as a mediating variable that supports the indirect effects.


Asunto(s)
Síndrome Metabólico , Índice de Severidad de la Enfermedad , Sueño , Humanos , Síndrome Metabólico/epidemiología , Síndrome Metabólico/complicaciones , Femenino , Masculino , Adulto , Sueño/fisiología , Persona de Mediana Edad , Factores de Riesgo , Análisis de Clases Latentes , Estudios de Cohortes , Ejercicio Físico , Factores de Tiempo , Duración del Sueño
20.
Support Care Cancer ; 32(8): 501, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38985345

RESUMEN

OBJECTIVE: This study aims to use structural equation modeling to explore the pathways and effect sizes of factors influencing the adherence of postoperative patients with digestive tract tumor to oral nutritional supplements, providing a theoretical basis for future nursing intervention measures. METHODS: A total of 300 postoperative patients with digestive tract tumor within 30 days after surgery were conveniently sampled. Surveys were conducted using a General Information Questionnaire, Morisky Medication Adherence Scale, Digestive System Tumor Patient Nutrition Knowledge-Attitude-Behavior Questionnaire, Multidimensional Social Perception Scale, Beliefs about Medical Questionnaire, and General Self-Efficacy Scale. Structural equation modeling was employed to analyze the factors and pathways affecting adherence with oral nutritional supplements. RESULTS: The adherence score of postoperative patients with digestive tract tumor to oral nutritional supplements was 1.61 ± 1.38. The structural equation model had a good fit (χ2/df = 2.685, GFI = 0.930, CFI = 0.913, AGFI = 0.887, IFI = 0.915, and RMSEA = 0.075). Nutrition knowledge, social support, medication beliefs, and self-efficacy were found to be factors influencing adherence with oral nutritional supplements in postoperative patients with digestive tract tumor, with total effects of 0.539, 0.264, 0.215, and 0.180, respectively. Nutrition knowledge indirectly affected adherence through self-efficacy and medication beliefs, while social support indirectly affected adherence through self-efficacy. CONCLUSION: Adherence with oral nutritional supplements in postoperative patients with digestive tract tumor is at a low level. Improving social support, enhancing patients nutrition knowledge, increasing self-efficacy, and strengthening medication beliefs are effective ways to improve patient adherence.


Asunto(s)
Suplementos Dietéticos , Conocimientos, Actitudes y Práctica en Salud , Cumplimiento de la Medicación , Autoeficacia , Humanos , Estudios Transversales , Femenino , Masculino , Persona de Mediana Edad , Cumplimiento de la Medicación/estadística & datos numéricos , Encuestas y Cuestionarios , Anciano , Adulto , Neoplasias del Sistema Digestivo/cirugía , Neoplasias del Sistema Digestivo/psicología , Apoyo Social , Neoplasias Gastrointestinales/cirugía , Neoplasias Gastrointestinales/psicología , Periodo Posoperatorio
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