Additive Model Research Articles

Projected Changes of Kuroshio in a Warming Climate

Abstract The projected changes in the Kuroshio and the associated mechanisms in response to future warming scenarios remain unclear. While some studies propose a negative midlatitude wind stress curl (WSC) tendency could expedite Kuroshio recirculation, others suggest that the isopycnal transport of warmer subtropical mode water (STMW) to the east of the Kuroshio enhances only the velocity in the upper ocean. In the future projections under the shared socioeconomic pathways 5-8.5 (SSP5-8.5) within phase 6 of Coupled Model Intercomparison Project (CMIP6) model ensemble, a consistent enhancement of the Kuroshio along the Japanese coast (JP-Kuroshio) is observed. Particularly, the response of the JP-Kuroshio to WSC changes is more pronounced in high-resolution (HR) models than low-resolution (LR) ones. However, diverse results emerge in the East China Sea (ECS-Kuroshio). While most CMIP6 HR models indicate a reduction of Kuroshio within the upper 1000 m in the ECS-Kuroshio, the ensemble of CMIP6 LR models shows an intensification of Kuroshio within the upper 300 m and a deceleration below, suggesting a consistent baroclinic feature in ECS-Kuroshio. Additional ocean model sensitivity experiments confirm that the WSC influences the Kuroshio throughout the entire water column, particularly below 300 m. Within the upper 300 m, the primary driver of Kuroshio changes is the surface warming, aligning with the STMW mechanism. Moreover, the surface salinity flux may also play an important role in the dynamics of Kuroshio changes.

Association of Initial Side of Brain Atrophy With Clinical Features and Disease Progression in Patients With GRN Frontotemporal Dementia.

Pathogenic variants in the GRN gene cause frontotemporal dementia (FTD-GRN) with marked brain asymmetry. This study aims to assess whether the disease progression of FTD-GRN depends on the initial side of the atrophy. We also investigated the potential use of brain asymmetry as a biomarker of the disease. Retrospective examination of data from the prospective Genetic Frontotemporal Initiative (GENFI) cohort study that recruits individuals who carry or were at risk of carrying a pathogenic variant causing FTD. GENFI participants underwent a standardized clinical and neuropsychological assessment, MRI, and a blood sample test yearly. We generated an asymmetry index for brain MRI to characterize brain asymmetry in participants with or at risk of FTD-GRN. Depending on the side of the asymmetry, we classified symptomatic GRN patients as right-GRN or left-GRN and compared their clinical features and disease progression. We generated generalized additive models to study how the asymmetry index evolves in carriers and noncarriers and compare its models with others created with volumetric values and plasma neurofilament light chain. A total of 399 participants (mean age 49.7 years, 59% female) were included (63 symptomatic carriers, 177 presymptomatic carriers, and 159 noncarriers). Symptomatic carriers showed higher brain asymmetry (11.6) than noncarriers (1.0, p < 0.001) and presymptomatic carriers (1.0, p < 0.001), making it possible to classify most of them as right-GRN (n = 21) or left-GRN (n = 36). Patients with right-GRN showed more disease severity at baseline (β = 6.9, 95% CI 2.4-11.0, p = 0.003) but a lower deterioration by year (β = -1.5, 95% CI -2.7 to -0.31, p = 0.015) than patients with left-GRN. Brain asymmetry could be found in GRN carriers 10.4 years before the onset of the symptoms (standard difference 0.85, CI 0.01-1.68). FTD-GRN affects the brain hemispheres asymmetrically and causes 2 anatomical asymmetry patterns depending on the side of the disease onset. We demonstrated that these 2 anatomical asymmetry patterns present different symptoms, severity at the time of the first visit, and different disease courses. Our results also suggest brain asymmetry as a possible biomarker of conversion in GRN carriers.

Влияние направления печати на характер износа PLA-биоматериала, полученного методом FDM: исследование для имплантата тазобедренного сустава

Introduction: hip joint replacement surgery involves replacing the damaged joint with an implant that can re-create the joint's articulation functionality. 3D printing technology is more promising than the traditional manufacturing process when it comes to producing more complex parts and shapes. The goal of the current research project is to determine how quickly biomaterial implant can be manufactured using 3D printing for hip-joint replacement by studying the wear rate of parts manufactured using different printing orientations. Although there are several additive manufacturing technologies, fuse deposition modeling (FDM) technology has had a significant impact on healthcare, automotive industry, etc. This is mainly due to the adaptability of different polymer-based composite materials and its cost-effectiveness. Such 3D printed polymers need to be further studied to evaluate the wear rate depending on different 3D printing orientations. Polylactic acid (PLA) biomaterials were extensively studied to determine its suitability for use as hip joint materials. Purpose of the work: in this work, an experimental study was carried out on the effect of printing orientation on dry sliding wear of a polylactic acid (PLA) material obtained by fused deposition modeling (FDM) technology using the pin-on-disk (SS 316) scheme. In addition, experimental and empirical models are developed to predict the performance taking into account the influence of load and sliding speed. Grey relational analysis was used to determine the optimal parameters. The methods of investigation: the FDM printing was used to manufacture pins using different printing orientations. Printing direction refers to printing at angles of 0°, 45°, and 90°, while all other 3D printing parameters remained unchanged. Wear testing was performed using the pin-on-disk kinematic scheme. During the experiments, the normal pin load and disk rotation speed were varied. The experiments were methodically designed to study the effect of input parameters on the specific wear rate. About 13 experiments were conducted for each printing orientation with a friction path of 4 kilometers, in the load range of 400–800 N, at a sliding speed of 450–750 rpm. Result and discussion: the study provides important results especially regarding the direction of 3D printing of components. It was found that the lowest sliding wear was observed for the pin printed at an angle of 0°, while slightly higher wear was observed for the pin printed at an angle of 90°. The layer bonding in the pin printed at an angle of 45° deformed under higher load, mainly due to an increase in temperature. The low bond strength in the pin printed at an angle of 45° resulted in high sliding wear. The optimal result was achieved at a sliding speed of 451 rpm and a load of 600 N. The results of the study are very useful for choosing materials for 3D printing of biomedical implants, medical and industrial products.

Towards a social dialectometry: the analysis of internal border effects

We aim to broaden the scope of border studies in dialectology and show that intra-state political borders can impact dialect continua as significantly as inter-state political borders. Our analysis focuses on the processes of language change currently taking place on either side of the Catalonia-Aragon border in Spain. We aim to bring dialectometry and sociolinguistics closer together by using generalized additive mixed-effects regression modelling allowing us to simultaneously analyze a large corpus of items and assess which social variables are responsible for this internal border effect. Firstly, our results confirm that the internal border between Catalonia and Aragon, arising from two simultaneous processes of vertical advergence (towards standard Catalan in Catalonia and towards standard Spanish in Aragon), has a stronger effect than the international border between Spain and Andorra. This emphasizes the need to investigate internal borders in linguistic convergence and divergence studies. Secondly, our findings indicate that the main predictors of change are the speakers’ year and birth region. This provides evidence that the border effect should be attributed, more than any other social factor, to the long-term consequences of belonging to distinct administrations. Finally, after comparing various indicators of the sociolinguistic evolution of the Aragonese Catalan dialects, we conclude that in this process of language shift, the decline in ethnolinguistic vitality of the recessive language correlates with an increase in structural hybridization caused by advergence towards the expanding language. This prompts further exploration into whether hybridization is a cause, mechanism, or result of the processes of language substitution.

Adolescent maturation of dorsolateral prefrontal cortex glutamate:GABA and cognitive function is supported by dopamine-related neurobiology.

Developmental changes in prefrontal cortex (PFC) excitatory (glutamatergic, Glu) and inhibitory (gamma- aminobutryic acid, GABA) neurotransmitter balance (E:I) have been identified during human adolescence, potentially reflecting a critical period of plasticity that supports the maturation of PFC-dependent cognition. Animal models implicate increases in dopamine (DA) in regulating changes in PFC E:I during critical periods of development, however, mechanistic relationships between DA and E:I have not been studied in humans. Here, we used high field (7T) echo planar imaging (EPI) in combination with Magnetic Resonance Spectroscopic Imaging (MRSI) to assess the role of basal ganglia tissue iron-reflecting DA neurophysiology-in longitudinal trajectories of dorsolateral PFC Glu, GABA, and their relative levels (Glu:GABA) and working memory performance from adolescence to adulthood in 153 participants (ages 10-32 years old, 1-3 visits, 272 visits total). Using generalized additive mixed models (GAMMs) that capture linear and non-linear developmental processes, we show that basal ganglia tissue iron increases during adolescence, and Glu:GABA is biased towards heightened Glu relative to GABA early in adolescence, decreasing into adulthood. Critically, variation in basal ganglia tissue iron was linked to different age-related trajectories in Glu:GABA and working memory. Specifically, individuals with higher levels of tissue iron showed a greater degree of age-related declines in Glu and Glu:GABA, resulting in lower Glu relative to GABA (i.e., higher GABA relative to Glu) in young adulthood. Variation in tissue iron additionally moderated working memory trajectories, as higher levels of tissue iron were associated with steeper age-related improvements and better performance into adulthood. Our results provide novel evidence for a model of critical period plasticity whereby individual differences in DA may be involved in fine-tuning PFC E:I and PFC-dependent cognitive function at a critical transition from adolescence into adulthood.

L-shaped relationship between atherogenic index of plasma with uric acid levels and hyperuricemia risk

BackgroundHyperuricemia is a major risk factor for cardiovascular disease. This study aimed to investigate the relationship between the atherogenic index of plasma (AIP) and serum uric acid (SUA) levels, as well as the risk of hyperuricemia.MethodsUtilizing data from the National Health and Nutrition Examination Survey (NHANES), we conducted a cross-sectional study involving 9,439 participants aged 18 years and above with complete triglyceride (TG) and high-density lipoprotein cholesterol (HDL-C) data. AIP was calculated as the logarithm of the ratio of TG to HDL-C. Weighted linear regression, weighted logistic regression, subgroup analysis, generalized additive model, restricted cubic spline and two-part linear and logistic regression were utilized to examine the relationships between AIP and SUA levels and hyperuricemia risk.ResultsWe identified a non-linear and L-shaped relationship between AIP and both SUA levels and hyperuricemia prevalence, with significant increasing observed up to a saturation point (0.588 for uric acid levels and 0.573 for hyperuricemia prevalence). Below these thresholds, the odds ratios (OR) for increased SUA and hyperuricemia were 0.854 (95% confidence interval [CI]: 0.762, 0.946) and 4.4 (95% CI: 3.528, 5.488), respectively (P&amp;lt;0.001). Beyond these points, the associations were not statistically significant.ConclusionOur findings suggest that AIP is significantly and non-linear associated with SUA levels and hyperuricemia risk, with a saturation effect observed beyond specific thresholds. These insights could inform clinical strategies for managing cardiovascular and metabolic risks associated with elevated AIP. Further longitudinal studies are warranted to confirm these associations and elucidate the underlying mechanisms.

Global Study Revolutionizes Bankruptcy Prediction

This study evaluates bankruptcy potential in food and beverage companies listed on the Indonesia Stock Exchange during 2018-2022 using four methods: Grover, Springate, Zmijewski, and Altman. Analyzing data from 31 sampled companies, the research employs descriptive quantitative methods and SPSS 26 analysis. Findings reveal varied bankruptcy predictions: Grover predicts 3 potential bankruptcies, Springate identifies 18, Zmijewski finds none, and Altman predicts 14. Notably, Zmijewski's method demonstrates superior accuracy. These results aid investors in understanding company performance and inform future financial strategies, addressing a critical need in early bankruptcy prediction for the food and beverage industry. Future research may explore additional prediction models and extend the study period to enhance predictive accuracy further. Highlight: Diverse methods: Grover, Springate, Zmijewski, Altman offer varied bankruptcy predictions. Zmijewski's accuracy: Highest accuracy among methods for bankruptcy prediction. Investor insight: Guides future financial decisions based on company performance analysis. Keywoard: Bankruptcy, Food &amp; beverage, Stock Exchange, Analysis, Prediction.

A REVIEW OF ADDITIVE MANUFACTURING TECHNOLOGIES AND THEIR APPLICATIONS IN THE MEDICAL FIELD

This review paper contains a literature survey about some additive manufacturing technologies and their medical use. Additive Manufacturing is a generic term referring to several technologies used to create physical models or prototype parts based on 3D drawings. Additive Manufacturing models can be used for various testing methods. The paper summarizes the application of Additive Manufacturing Technologies in medicine. It describes the main steps for how to create 3D models for medical applications. Some details can be found on the topics: Data acquisition using medical scanners; Data transformation; Creation of virtual 3D models; Surgical planning and simulation on the virtual 3D model; and Creation of Physical 3D Models for Additive Manufacturing Technologies. 3D physical models can be extremely useful in planning complex surgical interventions, which can be simulated on these models before the actual procedure.

Associations between dietary macronutrient composition and cardiometabolic health: data from NHANES 1999–2014

PurposeDietary macronutrients significantly impact cardiometabolic health, yet research often focuses on individual macronutrient relationships. This study aimed to explore the associations between dietary macronutrient composition and cardiometabolic health.MethodsThis study included 33,681 US adults (49.7 ± 18.3 years; 52.5% female) from the National Health and Nutrition Examination Survey during 1999–2014. Dietary data was derived from 1 to 2 separate 24-hour recalls and cardiometabolic health included lipid profile, glycemic control, blood pressure, and adiposity collected in a mobile examination center. Associations between dietary macronutrient composition and cardiometabolic health were examined using generalized additive models adjusted for age, socio-demographics, lifestyle, and diet quality.ResultsIn females, triglycerides (P < 0.01) and HDL cholesterol (P < 0.01) were the least optimal in diets containing lower fat (10%) and higher carbohydrate (75%). In males, HDL cholesterol was positively associated with fat (P < 0.01) and no association with triglycerides was detected. Total-C associations were male specific (P = 0.01) and highest in diets composed of 25% protein, 30% carbohydrate, and 45% fat. In both sexes, systolic blood pressure (P ≤ 0.02) was highest in diets containing lower fat (10%) coupled with moderate protein (25%). Diastolic blood pressure associations were female specific (P < 0.01) with higher values in those consuming the upper range of fat (55%). There were no associations of macronutrient composition with glycemic control or adiposity.ConclusionThis study revealed sex-specific relationships between macronutrient composition and cardiometabolic health. Future research is needed to explore these relationships across age groups.

A Non-Linear Exploration of the Digital Economy’s Impact on Agricultural Carbon Emission Efficiency in China

As the global climate crisis intensifies, improving agricultural carbon emission efficiency has become crucial for achieving the sustainable development goals (SDGs). This study investigates the complex, non-linear relationship between China’s digital economy and agricultural carbon emission efficiency, utilizing panel data from Chinese provinces spanning 2012–2022. We employ a multi-method approach, including the Super-SBM model for efficiency measurement, two-way fixed effects models, quantile regression, and Generalized Additive Models (GAMs) for empirical analysis. Our findings reveal: (1) The digital economy significantly enhances agricultural carbon emission efficiency, but with distinct non-linear characteristics across different dimensions. (2) The impact varies among digital economy aspects: the digital economy foundation shows the most substantial influence, followed by the rural digital industry level, while rural digital infrastructure has a relatively minor effect. (3) A threshold effect is observed, with the digital economy’s impact more pronounced in regions with higher agricultural carbon emission efficiency. (4) GAM analysis unveils complex non-linear patterns: the rural digital industry’s impact initially decreases before increasing, the digital economy foundation shows an overall increasing trend with plateaus, and rural digital infrastructure exhibits a near-linear relationship. (5) Sensitivity analysis indicates that agricultural carbon emission efficiency is most responsive to changes in the digital economy foundation, followed by the rural digital industry level. These findings provide nuanced insights into the digital economy’s role in enhancing agricultural sustainability. We propose targeted policy recommendations, including accelerating rural digital infrastructure development, optimizing the rural digital industry structure, and implementing context-specific digital facility construction. These strategies aim to fully leverage the digital economy’s potential in improving agricultural carbon emission efficiency, contributing to China’s “dual carbon” goals and sustainable agricultural development.

Neurodegeneration in the cortical sulcus is a feature of chronic traumatic encephalopathy and associated with repetitive head impacts

Neurodegeneration is a seminal feature of many neurological disorders. Chronic traumatic encephalopathy (CTE) is caused by repetitive head impacts (RHI) and is characterized by sulcal tau pathology. However, quantitative assessments of regional neurodegeneration in CTE have not been described. In this study, we quantified three key neurodegenerative measures, including cortical thickness, neuronal density, and synaptic proteins, in contact sport athletes (n = 185) and non-athlete controls (n = 52) within the sulcal depth, middle, and gyral crest of the dorsolateral frontal cortex. Cortical thickness and neuronal density were decreased within the sulcus in CTE compared to controls (p’s < 0.05). Measurements of synaptic proteins within the gyral crest showed a reduction of α-synuclein with CTE stage (p = 0.002) and variable changes in PSD-95 density. After adjusting for age, multiple linear regression models demonstrated a strong association between the duration of contact sports play and cortical thinning (p = 0.001) and neuronal loss (p = 0.032) within the sulcus. Additional regression models, adjusted for tau pathology, suggest that within the sulcus, the duration of play was associated with neuronal loss predominantly through tau pathology. In contrast, the association of duration of play with cortical thinning was minimally impacted by tau pathology. Overall, CTE is associated with cortical atrophy and a predominant sulcal neurodegeneration. Furthermore, the duration of contact sports play is associated with measures of neurodegeneration that are more severe in the cortical sulcus and may occur through tau-dependent and independent mechanisms.

Dimensions of Audit Committee Quality and CEO Compensation: Examining the Linear Relationship

This study examined the linear relationship between audit committee attributes, proxied with audit committee female diversity, audit committee diligent meeting, audit committee independence and audit committee size and Chief Executive Officer’s compensation, with firm size as a control variable. The study utilised data from 53 non-financial firms between 2013 and 2022 listed in the Nigerian Exchange Group. Using, STAT 14, the study also presented the descriptive statistics information, the correlation matrix and results of Random-effects GLS regression of the study. The results indicate that approximately 6.88% of the variation in Chief Executive Officer’s compensation can be explained by the combined effect of the independent variables, as evidenced by an R-squared value of 0.0688 and an adjusted R-squared of 0.0599. The model’s overall significance is confirmed by an F-statistic of 7.75 and a very low P-value (0.0000), we therefore reject the null hypothesis. The findings reveal that audit committee female diversity, audit committee diligent meeting, and audit committee independence do not have significant linear relationships with CEO compensation, as indicated by their respective P-values (0.542, 0.814, and 0.916). However, audit committee size displays a statistically significant negative linear relationship with CEO compensation (P = 0.000), suggesting that larger audit committees may be associated with lower CEO compensation due to increased oversight or stronger corporate governance structures. Consequently, further investigation with additional variables or alternative modelling approaches is recommended to gain deeper insights into other determinants of CEO compensation.

Resilience or Collapse? Reconstructing the Water Quality Time Series of a Tropical River Impacted by a Mine Tailings Dam Failure

The 2015 Fundão tailings dam collapse in Mariana, Brazil, was a major environmental catastrophe. Assessing its long-term effects on water quality is critical for environmental restoration and policy development. In this study, we reconstructed a 15-year time series of five water quality parameters to assess whether the collapse caused permanent changes. Using public data from the Minas Gerais Water Institute (IGAM), we fitted generalized additive models for location, scale, and shape to model long-term trends in turbidity, total solids, conductivity, pH, and dissolved oxygen. Predictor variables included daily precipitation and smooth functions for time and longitudinal distance along the river. As expected, turbidity and total solids increased sharply after the collapse; however, the mean values returned to pre-collapse levels within four years. Conductivity, which was already elevated pre-collapse, remained high following the passage of the tailings plume. Although we observed a tendency toward pre-collapse values, the long-term conductivity mean did not fully stabilize to previous levels. No clear patterns were observed for pH or dissolved oxygen. This study highlights the acute impact of the dam collapse on five water quality parameters in the Doce River and illustrates the river’s subsequent stabilization process, although other important and chronic impacts are still persistent. Long-term studies such as this provide valuable insights into the dynamics of fluvial systems.

Additive interaction of family medical history of cardiovascular diseases with hypertension and diabetes on the diagnosis of cardiovascular diseases among older adults in India

IntroductionThe present study aimed to examine the additive interaction of family medical history of cardiovascular disease (CVD) and self-reported hypertension and diabetes on the diagnosis of CVD among older adults aged 45 years and above in India. A family medical history of CVD in individuals with hypertension and diabetes could identify a subpopulation with a higher risk of CVD.MethodsThe study used the data from the Longitudinal Ageing Study in India (LASI) Wave 1 (2017–2018). The total sample size for the study was 58,734 older adults aged 45 years and above. An additive model was applied to determine the additive interaction effect of the family medical history of CVD with hypertension and diabetes on the diagnosis of CVD by calculating three different measures of additive interaction: the relative excess risk due to interaction (RERI), attribution proportion due to interaction (AP), and synergy index (S).ResultsThe prevalence of CVD was higher among hypertensive individuals with a family medical history of CVD (18.6%) than individuals without the coexistence of family medical history of CVD and hypertension (4.7%), and hypertensive individuals without family medical history of CVD (11.3%). On the other hand, the prevalence of CVD was higher among individuals with diabetes and family history of CVD (20.5%) than individuals without the coexistence of family history of CVD and diabetes (5.0%). Individuals with parental and sibling medical history had two times higher odds of having chronic heart diseases and strokes, respectively than those without parental and sibling history. In the adjusted model, RERI, AP, and S for CVD were 2.30 (95% CI: 0.87–3.74), 35% (0.35; 95% CI: 0.20–0.51), and 1.71 (95% CI: 1.27–2.28) respectively, demonstrating significant positive interaction between family medical history and hypertension on the diagnosis of cardiovascular diseases.ConclusionsThe present study revealed that in the additive model, the interaction effects of family medical history and hypertension were significantly positive on cardiovascular diseases even after adjustment with potential confounding factors. Therefore, it is crucial to consider the presence of family medical history of CVD among individuals with hypertension and diabetes measured in research and clinical practice.

Kernel density regression in the additive model: a B-spline approach

Kernel density regression in the additive model: a B-spline approach

Dissection of X chromosome dosage compensation for quantitative traits in sheep using different statistical models

Since males and females have different number of X chromosome, different mechanisms have evolved to equalize dosage of gene products from the X chromosome between XX females and XY males. The aim of this study was to study X chromosome dosage compensation for growth rate (GR), Kleiber ratio (KR), efficiency of growth (EF) and relative growth rate (RGR) in Zandi sheep. A two steps procedure was adopted to analysis data. In the first step, each trait was analyzed with a series of 6 animal models including different combinations of direct and maternal effects. Using Akanke’s Information Criterion (AIC) the best model (Model I) was selected for each trait. In the second step, five additional models were fitted by adding X chromosome effects to the Model I, considering 5 strategies for modeling X chromosome dosage compensation: (1) no global dosage compensation (ngdc), (2) random inactivation in the homogametic sex (hori), (3) doubling of the single shared sex chromosome in the heterogametic sex (hedo), (4) halving expression of both sex chromosomes in the homogametic sex (hoha) or (5) inactivation of the paternal sex chromosome in the homogametic sex (hopi). Predictive ability of models was measured using the mean squared error of prediction (MSE) and Pearson’s correlation coefficient between the real and predicted values of records Correlations between traits due to autosomal- and X-linked genetic effects were estimated by bi-variate analyses. For GR and KR, models including X-linked effects lead to a much better fit of data, expressed by the strong decrease in the AIC criterion. Models including X-linked effects had also better predictive ability as they provided smaller MSE and higher For GR and KR, although all strategies for modeling X chromosome dosage compensation improved general properties of the model, the model “ngdc” fitted the data significantly better than other models. Including X-linked genetic effects in the model led to 10% (GR, KR) decrease in the autosomal additive variance, and 7% (KR) to 19% (GR) decrease in the residual variance. Estimates of autosomal heritability (), were 0.15 ± 0.03, 0.13 ± 0.03, 0.9 ± 0.03 and 0.13 ± 0.03 for GR, KR, EF and RGR, respectively. X-linked heritability () was 0.08 ± 0.03 for GR and 0.04 ± 0.03 for KR, respectively. Maternal heritability () were 0.02 ± 0.01, 0.01 ± 0.01, 0.03 ± 0.02 and 0.03 ± 0.02 for GR, KR, EF and RGR, respectively. For GR and KR, the Spearman’s correlation between breeding values obtained from the best model and model I deviated from unity, indicating re-ranking of top animals across models. The X-linked additive genetic correlation and autosomal additive genetic correlation were similar in terms of sign and magnitude in a way that they were all positive and high. As considering X-linked genetic effects resulted to an improvement in the general properties of the model and possibility of re-ranking of top animals, including these effects in the model, considering dosage compensation on the X chromosome was recommended.

Pacific nurse sharks Ginglymostoma unami exhibit yearly patterns of site fidelity to a tropical embayment subjected to seasonal upwelling

Seasonal upwelling in tropical coastal regions can create dynamic oceanographic conditions similar to temperate systems, which are known to influence the distribution and movement of marine species. Mobile marine species may seek warmer environments (i.e. exhibit behavioral thermoregulation) in response to stronger winds during the upwelling season, which cause cold, nutrient-rich waters to rise and cool shallower environments. Pacific nurse sharks Ginglymostoma unami are present in the upwelling regions of the Eastern Tropical Pacific coastline, serving as an ideal model species to study the effects of changing water temperatures on movement behavior. In this study, we analyzed 4 yr of passive acoustic telemetry data to quantify the movement, residency, and habitat use of G. unami in Santa Elena Bay, north Pacific coast of Costa Rica, located within the Papagayo upwelling system. A total of 28 sharks (15 males and 13 females) ranging from 85 to 256 cm total length were monitored inside the bay. The mean (±SD) residency index (i.e. number of days detected relative to the number of days monitored) of individual sharks was 37 ± 28%. Generalized additive mixed models revealed seasonal and diel patterns of G. unami use of Santa Elena Bay that were associated with water temperature and wind speed changes during the upwelling season. G. unami likely uses the warmer waters of Santa Elena Bay as a thermal refuge during the upwelling season to avoid colder adjacent waters. This research will serve as a baseline to understand the movement behavior of this species as climate change alters upwelling patterns.

The relationship of serum klotho levels and triglyceride glucose index-related indicators

BackgroundKlotho, an anti-aging protein, is linked to energy metabolism. There is limited research on the association of serum klotho and triglyceride glucose (TyG) index-related indicators. Our research aims to investigate the relationship of serum klotho with TyG-BMI (body mass index), TyG-WC (waist circumference), and TyG-WHtR (waist-to-height ratio).MethodsFrom 2007 to 2016, we examined 6,370 participants in the National Health and Nutrition Examination Survey (NHANES). The enzyme-linked immunosorbent assay (ELISA) was utilized to measure serum klotho. We calculated the TyG-BMI, TyG-WC, and TyG-WHtR based on fasting triglycerides, fasting glucose, BMI, WC, and WHtR. Multiple linear regression analysis was used to evaluate the association of serum klotho with TyG-BMI, TyG-WC, and TyG-WHtR. Additionally, generalized additive model (GAM) and smoothing curves were used to evaluate the linear and nonlinear relationships. A piecewise regression model was also utilized to test for threshold effects and determine the breakpoints. Finally, the potential independent associations of serum klotho with TyG-BMI, TyG-WC, and TyG-WHtR were further explored using subgroup analysis.ResultsWe observed a statistically significant difference in serum klotho levels across different quartiles of the population. Based on the multiple linear regression analysis, serum klotho levels were negatively associated with TyG-related indicators. There was a nonlinear relationship between the serum klotho and TyG-BMI, TyG-WC, and TyG-WHtR. The segmented regression analysis revealed that the breakpoints of TyG-BMI, TyG-WC, and TyG-WHtR were 5.42, 6.67, and 1.89, respectively. Subgroup analysis showed that TyG-related indicators interacted with gender and diabetes.ConclusionsIn this study, a negative and nonlinear relationship was identified between serum klotho and TyG-related indicators. Further research is needed to clarify the potential mechanisms that may link serum klotho to TyG-BMI, TyG-WC, and TyG-WHtR.

NONPARAMETRIC IDENTIFICATION AND ESTIMATION OF A GENERALIZED ADDITIVE MODEL WITH A FLEXIBLE ADDITIVE STRUCTURE AND UNKNOWN LINK

This paper proposes a nonparametric approach to identify and estimate the generalized additive model with a flexible additive structure and with possibly discrete variables when the link function is unknown. Our approach allows for a flexible additive structure which provides applied researchers the flexibility to specify their model according to economic theory or practical experience. Motivated by the concerns from empirical research, our method also allows for multiple discrete variables in the covariates. By transforming our model into a generalized additive model with univariate component functions, our identification and estimation thereby follows a procedure adapted from the case with univariate components. The estimators converge to normal distributions in large sample with a one-dimensional convergence rate for the link function and a $d_k$ -dimensional convergence rate for the component function $f_k(\cdot )$ defined on ${\mathbb R}^{d_k}$ for all k.

Nonlinear relationship between diabetes mellitus duration and diabetic retinopathy

To investigate the non-linear relationship between diabetes mellitus (DM) duration and the development of diabetic retinopathy (DR). By investigating the association between these variables, our goal is to contribute to the existing knowledge regarding the impact of DM duration on the development and severity of DR. A retrospective cross-sectional study was conducted on 420 patients in the Department of Endocrinology at Guangdong Provincial People’s Hospital, who had undergone ophthalmic consultations from December 2017 to November 2018. The analysis of DM duration and DR utilized a generalized additive model to identify both linear and non-linear connections. The threshold effect was determined using a two-piece regression model. The study included a total of 420 patients, with a mean age of 58.7 years. Of these, 56.9% (239/420) were male. The prevalence of DR was 38.33% (161/420). After adjusting for confounding factors, a nonlinear relationship between DM duration and DR was observed, with a turning point at 8 years. On the left side of the turning point, the prevalence increased by 24% per 1-year increase in DM duration (OR: 1.24; 95% CI: 1.11–1.38; P<0.0001). However, no statistically significant differences were found on the right side of the turning point (OR: 1.02; 95% CI: 0.97–1.08; P = 0.4987). Our study identified a non-linear relationship between DM duration and DR in patients. When the DM duration is less than 8 years, a positive correlation exists between DM duration and DR. However, once the DM duration exceeds 8 years, the effect reaches saturation, and no significant correlation is observed.