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Open Access May 13, 2025

Geochemistry distributions and statistics analysis of REE in stream sediments from the watershed west of Mambaka (Adamawa Plateau, Cameroun)

Abstract The Mambaka watershed is extends between latitudes 1 3°45'E and 14°15'E and longitudes 7°16'N and 6°45'N. The geology, various tectonic and structural events that have affected the Adamawa Plateau in Cameroon make it rich in multi-substance mining. The objective of this study is to map rare earth (REE) geochemical anomalies in the sediments of the watershed streams west of Mambaka, and to trace [...] Read more.
The Mambaka watershed is extends between latitudes 1 3°45'E and 14°15'E and longitudes 7°16'N and 6°45'N. The geology, various tectonic and structural events that have affected the Adamawa Plateau in Cameroon make it rich in multi-substance mining. The objective of this study is to map rare earth (REE) geochemical anomalies in the sediments of the watershed streams west of Mambaka, and to trace their origins and geochemical processes. Predictive maps from inverse distance interpolations (IDW), factor analysis (F1) or principal component analysis (PCA) and hierarchical bottom-up classification maps provided a better understanding of the central tendency, distribution and dispersion of REE in the samples and in the study area, based on standard deviation and variance values that generated two factors F1 (Ho-Tm-Er-Yb-Lu-Dy-Tb-Gd-Eu-Sm) and F2 (Pr-Nd-Ce-La-Sm) representing 92.44% of the total cumulative variance. The ratios Ce/Ce* > 0.78 and Eu/Eu* > 1 demonstrate positive anomalies in Ce and Eu, and clear differentiation. The normalized concentrations used to calculate fractionation ratios show that the values for LaN/YbN (0.58 to 1.34), LaN/SmN (0.61 to 0.88) and LaN/LuN (0.62 to 1.43) suggest higher fractionation in SS09 and lower fractionation in SS01. Similarly, the ratios La/Lu (61.71 to 143.46), La/Yb (9.00 to 20.72), La/Sm (4.02 to 5.83) and La/ Lu (61.71 to 143.46) confirm these higher ratios in SS09 and lower in SS01. The REE in the study area comes from hydrothermal processes based on high lineament densities at sampling points in igneous rocks with a mean ∑REE value of between 174-219 ppm.
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Open Access January 23, 2025

Brain-Wide Resting-State Functional Connectivity Partially Mediates Socioeconomic Disparities in Children's Cardiometabolic Health

Abstract Background: Although some neural mechanisms underlying socioeconomic status (SES) disparities are known, the role of brain-wide resting-state functional connectivity in these effects remains less understood. Aim: This study aims to identify brain-wide resting-state functional connectivity signatures that may mediate the effects of SES on body mass index (BMI) and blood pressure in [...] Read more.
Background: Although some neural mechanisms underlying socioeconomic status (SES) disparities are known, the role of brain-wide resting-state functional connectivity in these effects remains less understood. Aim: This study aims to identify brain-wide resting-state functional connectivity signatures that may mediate the effects of SES on body mass index (BMI) and blood pressure in children, using data from the Adolescent Brain Cognitive Development (ABCD) study. Methods: Data were drawn from the ABCD study, a large, diverse cohort of children aged 9-10. Pre-processed resting-state functional MRI data were used, and factor analysis was conducted to extract a whole-brain connectivity factor. The first factor, capturing the greatest variance in brain-wide resting-state connectivity, was selected for further analysis in a structural equation model (SEM). This connectivity factor was tested as a potential mediator of the relationship between SES (measured by parental education, family income, and neighborhood characteristics) and two indicators of cardiometabolic health: BMI and systolic blood pressure. Results: Factor analysis revealed a robust first factor that accounted for a significant proportion of variance in brain-wide resting-state functional connectivity. This factor was significantly associated with SES, indicating that children from lower SES backgrounds exhibited distinct connectivity patterns. Additionally, the factor was linked to both BMI and systolic blood pressure, suggesting its relevance to cardiometabolic health. Mediation analysis showed that this connectivity factor partially mediated the relationship between SES and both BMI and systolic blood pressure. Conclusions: Brain-wide functional connectivity may be a mediator of SES effects on BMI and blood pressure in children. The first connectivity factor provides a promising neural signature linking SES with cardiometabolic risk. Comprehensive brain-wide approaches to functional connectivity may offer valuable insights into how social determinants of health shape neural and physical development in childhood.
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Open Access October 22, 2023

An Appraisal of Work-Family Conflict on Management Staff of Star-Rated Hotels

Abstract The objective of this research was to investigate work-family conflict among management staff of hotels in the Accra Metropolis of Ghana. The study employs the pragmatism approach and Convergent parallel mixed methods research technique. The population of the study is all-star-rated management staff of star-rated hotels in the Accra metropolis. Stratified, random and convenient sampling techniques [...] Read more.
The objective of this research was to investigate work-family conflict among management staff of hotels in the Accra Metropolis of Ghana. The study employs the pragmatism approach and Convergent parallel mixed methods research technique. The population of the study is all-star-rated management staff of star-rated hotels in the Accra metropolis. Stratified, random and convenient sampling techniques were used to select 182 out of 356 respondents. One hundred (100) were sampled using a formula and a table determination of sample size based on the confidence level needed from a given population as provided by Krejcie and Morgan in 1970 for the study. Ten managers were conveniently interviewed on the issues of work-family conflict. The main instruments for data collection were a questionnaire and a semi-structured interview guide. This study adopted factor analysis and a structural equation model to examine factors that influence work-family conflict. This statistical technique was used in the research to investigate the factorability of the variables of work-related and family-related factors separately and a structural equation model was used to combine both factors to better understand the relationship. Linear regression was used to determine the relationship between work-family conflict. Pearson product-moment Correlation and structural equation model were used to determine the consequences of work-family conflict. It can be concluded that both work-related such as work overload, job type and involvement as well as family-related factors such as life cycle stage, and childcare arrangement predict work-family conflict among managers of hotels in the Accra metropolis. It is also deducted WFC affect managers’ performance on the job, exhaust them emotionally and also influences their intentions to leave the job for another. Managers usually feel fatigued to prepare for work and physically drained after work. They also feel depressed and emotionally drained sometimes. It is recommended that top management of hotels should allocate a budget to build an organisational culture that encourages work-family balance. Frontline managers should be trained to be aware of the benefit of providing support in the work environment that will help staff balance work and family. It is also recommended that hotel jobs be redesigned by the human resource unit to reduce workload and make it more interesting for managers so they may not feel overworked. Overworking of managers will enhance their intentions to quit the job and this will be costly for hotels.
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Keyword:  Factor Analysis

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