Inverted U-shaped Curve Research Articles

Does an environmental stringent policy really matter to achieve environmental sustainability in BRICS-T region? Evidence from novel method of moments quantile regression approach

Amidst pressing global environmental challenges, exacerbated by climate change and the imminent threat of global warming, there is a critical need to assess the efficacy of environmental policies. This study centers its attention on the pivotal role of these policies in addressing environmental concerns. Specifically, our research aims to scrutinize the impact of stringent environmental policies on environmental quality under the theoretical underpinnings of environmental Kuznets curve. To achieve this objective, the study collected data from BRICS-T economies over the period of 1990–2020. This study employed the method of moments quantile regression technique for empirical analysis. Our study validates the presence of the Environmental Kuznets curve (EKC hypothesis). Empirical findings reveal the sustained significance of environmental stringency across all quantiles, demonstrating a positive correlation in lower quantiles and a negative correlation in higher quantiles. At lower quantiles, the impact is insignificant initially, but pronounced due to efficiency improvements induced by stringent policies. The effects became negative at middle quantiles, indicating stringent policies might encounter diminishing returns where policy measures start stabilizing ecological impacts. At higher quantiles, the influence of ESI remains significant, reflecting ongoing adaptations in larger economies with higher ecological footprints. This suggests the potential effectiveness of stringent regulatory measures in mitigating environmental impacts and reducing ecological footprints. The identified inverted U-shaped curve signifies that while stringent policies may not inherently enhance environmental health, beyond a certain threshold, they can indeed contribute to its improvement. Our policy recommendation advocates for the widespread adoption and promotion of such stringent measures to safeguard environmental health.

Exploring the (dis)advantages of smart cities’ inclusive, integrative and social practices in new business creation: the effect of human capital inflow

ABSTRACT The term ‘smart’ has become key in cities’ development policies. The need to adapt to an increasingly global and dynamic context is fundamental to cities’ survival and development trajectories. Nonetheless, how this goal should be met and how the ‘smart’ dimension in cities impacts the social, economic and urban levels are still subject to debate. In the present paper, we focus on the relationship between the ‘smart living’ dimension, which includes integrative, inclusive and social practices, and the promotion of a local entrepreneurial environment by considering the moderating role of intra- and international human capital inflow. Using a GLS method and a panel dataset that includes 30 cities, we demonstrate that the relationship tends to be an inverted U-shaped curve, contributing to the discussion on the impact of smart cities’ social policies on entrepreneurship in urban contexts. Furthermore, we highlight that human capital inflow positively moderates this relationship, showing that intra- and international human capital flows contribute differently in this regard, producing divergent effects. We conclude with implications for academics and policymakers, and practical and theoretical suggestions.

The neural compensation phenomenon in schizophrenia with mild attention deficits during working memory task

BackgroundWorking memory (WM) and attention are essential cognitive processes, and their interplay is critical for efficient information processing. Schizophrenia often exhibits deficits in both WM and attention, contributing to function impairments. This study aims to investigate the neural mechanisms underlying the relationship between WM impairments and attention deficits in schizophrenia. MethodsWe assessed the functional-MRI scans of the 184 schizophrenias with different attention deficits (mild=133; severe=51) and 146 controls during an N-back WM task. We explored their whole-brain functional connectome profile by adopting the voxel-wise degree centrality (DC). Linear analysis was conducted to explore the associations among attention deficit severity, altered DC, and WM performance in patients. ResultsWe observed that all patients showed decreased DC in the pre-supplementary area (pre-SMA), and posterior cerebellum compared to the controls, and schizophrenia patients with mild attention deficits showed decreased DC in the supramarginal gyrus, insula, and precuneus compared with the other 2 groups. DC values of the detected brain regions displayed U-shaped or inverted U-shaped curves, rather than a linear pattern, in response to increasing attention deficits. The linear analysis indicated that altered DC of the pre-SMA can modulate the relationship between attention deficits and WM performance. ConclusionThe U-shaped or inverted U-shaped pattern in response to increasing attention deficits may reflect a compensation mechanism in schizophrenia with mild attention deficits. This notion is also supported by the linear analysis that schizophrenia patients with mild attention deficits can improve their WM performance by increasing the DC value of the pre-SMA.

Systemic immune-inflammatory indicators and bone mineral density in chronic kidney disease patients: A cross-sectional research from NHANES 2011 to 2018.

The purpose of this study was to look at the relationship between the Systemic Immune Inflammatory Index (SII) and bone mineral density (BMD) in the pelvis, left upper and lower limbs, lumbar spine, thoracic spine, and trunk in a chronic kidney disease (CKD) population in the United States. The National Health and Nutrition Examination Survey (2011-2016) yielded 2302 people with CKD aged >18 years. CKD was defined as eGFR less than 90 ml/min/1.73 m2 or eGFR greater than 90 ml/min/1.73 m2 with urine ACR greater than 30 mg/L.SII was calculated as PC * (NC / LC) from platelet count (PC), neutrophil count (NC), and lymphocyte count (LC). Multiple logistic regression was used to examine the relationship between BMD and SII at different sites in CKD patients, smoothed curve-fitting and generalized weighting models were used to investigate non-linear relationships, and a two-tailed linear regression model was used to find potential inflection points in the model. We discovered a negative correlation between SII and pelvic BMD among 2302 participants after controlling for gender, age, and race [β = -0.008; 95% confidence value -0.008; 95% confidence interval (CI) -0.014, -0.002]. Lower PEBMD was related to increasing SII (trend p = 0.01125). After additional correction, only pelvic BMD remained adversely linked with SII [value -0.006; 95% CI -0.012, -0.000, p = 0.03368]. Smoothed curve fitting revealed a consistent inverse relationship between SII and pelvic BMD. Further stratified analyses revealed a substantial positive negative connection between SII and pelvic BMD in individuals who did not have hypertension, diabetes, a BMI of more than 30 kg/m2, or stage 2 CKD. The connection between SII and PEBMD in people without diabetes revealed a strong inverted U-shaped curve. In individuals with CKD in the United States, there was a negative connection between the systemic immunoinflammatory index (SII) and pelvic BMD. The SII might be a low-cost and simple test for CKD-related BMD loss.

Dynamic evolution of urban resilience and its coupling mechanism with EF3D-driven natural capital utilization: Case study in three typical urban agglomerations of China

Improving urban resilience (UR) and natural capital utilization are critical for supporting regional sustainable development. However, most of the previous studies have separately assessed them, and their coupling mechanism is still unclear. This study develops a cloud model-based urban resilience (UR) assessment framework to explore the dynamic evolution of UR in the three typical urban agglomerations of the Yangtze River Economic Belt (YREB). Natural capital utilization is analyzed by an improved ecological footprint (EF3D) model. Coupling Coordination Degree (CCD) and Environmental Kuznets Theory (EKC) are integrated for revealing the relationship between UR and natural capital utilization. Results show that UR in the YREB shows an increasing trend with an average annual rate of 1.33%, and there is a significant difference in the sub-dimensions of UR. Water system resilience generally has a positive impact on UR in the early periods, but its impact later becomes negative, with over 45% of all cities' UR being negatively affected by water system resilience. The spatial distribution of EF3D shows a decentralized trend in the YREB. The consumption of resource stocks represented by ecological footprint depth increases during the period from 2000 to 2015, with increase rates of 1.09%, 4.73%, and 3.42% for the upstream, midstream, and downstream urban agglomerations, respectively. The CCD between UR and natural capital utilization increases from an intermediate coordination stage to a well-coordinated stage. The EKC analysis discloses that UR and natural capital utilization present inverted U-shaped curves in three urban agglomerations with spatial differences. The inflection point of UR in the upstream is earlier (in 2008) than that in the midstream (in 2014) and downstream (in 2015) urban agglomerations. Findings can help quantify the development space for each city to enter into coordinated development in the future.

Association between dietary fiber intake and diabetic nephropathy among adult diabetes mellitus in the United States: A cross-sectional study

ObjectiveThere has been some evidence that dietary fiber may be associated with diabetic nephropathy (DN), but the relationship is still unclear. The purpose of this study was to examine the association between dietary fiber intake and DN. MethodsThis cross-sectional study used National Health and Nutrition Examination Survey (NHANES) data collected between 2007 and 2020. Weighted multivariate logistic regression was used to examine the relation between dietary fiber intake and DN. In addition, fitted smoothed curves were used to explore potential non-linear relationships. If non-linearity was observed, inflection points were further calculated by a recursive algorithm. ResultsThe study finally included 5964 subjects ≥20 years of age. The mean age was 60.8 ± 13.4 years with males (52.4 %), and non-Hispanic Whites (62.4 %), and the weighted prevalence of DN was 36.7 %. Dietary fiber was negatively associated with the risk of DN after controlling for all confounding variables (OR = 0.89, 95%CI: 0.80, 0.99). Smoothed curve fit plots of the dose relationship showed that dietary fiber intake was linearly related to DN, whereas males (inflection point of 8.0 g/d) and non-Hispanic Blacks (inflection point of 14.9 g/d) followed a non-linear inverted U-shaped curve relationship. In United States adults aged 20 and older, dietary fiber intake may be associated with a reduced risk of DN. ConclusionAppropriate increases in dietary fiber intake may offer potential benefits for DN. In conclusion, it appears that increasing dietary fiber intake may be one of the most effective strategies for the prevention and management of DN.

Assessment of the influence of institutions and globalization on environmental pollution for open and closed economies

As the environmental sustainability effectiveness of various political systems is taken into consideration, it is doubtful as to whether the presumption of the overall efficiency of democracy can be sustained in global governance architecture. The effectiveness of autocracies and democracies (i.e., governance indicators are compared in the present study) with reference to strengths and weaknesses in environmental objectives. This analysis explores the effect of autocracy, democracy, as well as the trend of globalization on CO2 emissions for open and closed economies from 1990 to 2020. Crucial indicators such as economic growth, renewable energy and non-renewable energy are controlled for while examining the roles of economic expansion on the disaggregated energy consumption portfolios for both open and closed economies. The empirical analysis revealed some insightful results. First, for the open economies, with the exception of non-renewable energy which shows a positive significant impact on emissions, all variables show a negative effect on emissions. Furthermore, the closed economies result indicate that, apart from renewable energy which has a negative relationship with emissions, all the variables including the interaction terms have a positive relation with emissions. However, an inverted U-shaped environmental Kuznets curve hypothesis was validated for both economies.

Linear and curvilinear association of pain tolerance and social anxiety symptoms among youth with different subgroups of childhood trauma

BackgroundSocial anxiety is a common symptom that occurs after exposure to childhood trauma (CT), and pain tolerance is a protective factor against social anxiety in generic populations with CT. However, few studies have investigated whether and how this association varies across different CT subgroups. Thus, this study aimed to investigate (1) the effects of pain tolerance on social anxiety symptoms among youth with different subgroups of CT; (2) the nonlinear relationship between pain tolerance and social anxiety symptoms among different CT categories. MethodsIn this study, 15,682 college or university students with experiences of CT were identified in a large sample and divided into five CT subgroups. Linear and quadratic regression models were conducted to explore the association between pain tolerance and social anxiety symptoms among youth with different CT subgroups. ResultsThe results of model revealed a linear relationship between pain tolerance and social anxiety symptoms among youth with most CT subgroups. Notably, an inverted U-shaped curve was found between pain tolerance and social anxiety symptoms in youth with emotional abuse. Social anxiety symptoms increased gradually with pain tolerance scores between 0 and 16, and then sharply decreased when scores reached above 16. LimitationsLimited by self-report measurements, the results of this study focused only on perceived pain tolerance and ignored behavioral pain tolerance. ConclusionThese findings highlight the importance of assessing pain tolerance thresholds in youth with emotional abuse and improving pain tolerance to prevent social anxiety symptoms in youth with different subgroups of CT.

Pay structure and firm technological innovation: comparative research based on three pay gaps

While previous research has extensively explored the correlation between pay gaps and firm innovation, the comprehensive investigation of various pay gaps within a unified framework remains an understudied domain. We advance the understanding of the intricate relationship between pay gaps and firm innovation by examining the tournament effect and social comparison effect. Through empirical analysis spanning the period from 2009 to 2019 of Chinese listed companies, our findings reveal a potential inverted U-shaped curve in the impact of all pay gaps on firm innovation. Specifically, the effects of internal pay gap and management pay gap exhibit the left half of an inverted U-shaped curve, while the external pay gap demonstrates a complete inverted U shape. Additionally, utilizing fsQCA, we unveil that small firms can stimulate innovation through management pay incentives, internal tournaments, or employee tournaments. Conversely, large firms can pursue diverse paths, including management equity incentives, strategic emphasis on low pay for firm growth, or a harmonious combination of management pay and equity incentives. The intricate interplay between pay gaps and firm innovation is contingent upon industry and firm characteristics. Consequently, our study underscores the importance of meticulously designing pay structures that align with strategic goals and unique attributes.

The Association Between Blood Mercury and Lipid Biomarkers in US Hypertensive Adults.

This cross-sectional research gathered data from a total of 4415 participants sourced from the National Health and Nutrition Examination Survey (NHANES). The Holm-Bonferroni stepdown procedure was utilized to control the type I error rate in multiple comparisons. We employed multivariable linear regression models to assess the correlation between blood Hg and lipid biomarkers. Subsequently, subgroup analyses were conducted, categorized by both gender and race. Additionally, we used smooth curve fittings and generalized additive models to confirm the presence of non-linear relationships. When non-linearity was detected, we applied a recursive algorithm to calculate the inflection points. Finally, we established a weighted two-piecewise linear regression model to illustrate the associations on either side of the inflection point. In our multivariable linear regression models, clear associations emerged. Specifically, positive correlations were observed between blood mercury and TC (β = 0.025; 95% CI 0.009 to 0.041; corrected P = 0.011), LDL-C (β = 0.022; 95% CI 0.007 to 0.036; corrected P = 0.012), and HDL-C (β = 0.007; 95% CI 0.001 to 0.013; corrected P = 0.058). However, there was no significant correlation with TG (β = - 0.007; 95% CI - 0.018 to 0.004; corrected P = 0.526). Notably, it has been demonstrated that distinct inverted U-shaped and U-shaped curves exist when stratified by gender in our analysis. Blood Hg exhibited a positive correlation with TC, LDL-C, and HDL-C in hypertensive adults in the USA. Nonetheless, no significant association was observed with TG.

N-Isopropylbenzylamine-induced conditioned place preference, sensitization behaviour and self-administration in rodents.

N-Isopropylbenzylamine (N-ipb), a chain isomer of methamphetamine (METH) with similar physical properties, has been used as a substitute for METH in seized drug samples. However, the abuse potential of N-ipb remains unclear. Therefore, this study aimed to evaluate the abuse potential of N-ipb in comparison to METH, by using conditioned place preference (CPP), locomotor sensitization and intravenous self-administration tests. The results showed that N-ipb at a dose of 3 mg·kg-1 significantly induced CPP in mice, which was comparable to the effect of METH at 1mg·kg-1 . Either acute or repeated N-ipb injections (1 or 3mg·kg-1 ) failed to raise the locomotor activity. However, acute treatment with 10mg·kg-1 N-ipb elevated the locomotor activity compared with saline, while chronic injection of 10mg·kg-1 N-ipb induced a delayed and attenuated sensitization compared with 1mg·kg-1 METH. Rats could acquire N-ipb self-administration at a dose of 1mg·kg-1 ·infusion-1 , and a typical inverted U-shaped dose-response curve was obtained for N-ipb. The mean dose of N-ipb that maintained the maximum response was greater than that of METH, indicating that N-ipb is less potent for reinforcement than METH. In the economic behavioural analysis, comparison of essential values derived from the demand elasticity revealed that N-ipb is less efficacy as a reinforcer than METH. The present data demonstrate that N-ipb functions as a reinforcer and has a potential for abuse. However, the potency of psychomotor stimulation and the reinforcing effectiveness of N-ipb are lower than those of METH.

A longitudinal study of the effect of visuomotor learning on functional brain connectivity.

Neural adaptation in the frontoparietal and motor cortex-sensorimotor circuits is crucial for acquiring visuomotor skills. However, the specific nature of highly dynamic neural connectivity in these circuits during the acquisition of visuomotor skills remains unclear. To achieve a more comprehensive understanding of the relationship between acquisition of visuomotor skills and neural connectivity, we used electroencephalographic coherence to capture highly dynamic nature of neural connectivity. We recruited 60 male novices who were randomly assigned to either the experimental group (EG) or the control group (CG). Participants in EG were asked to engage in repeated putting practice, but CG did not engage in golf practice. In addition, we analyzed the connectivity by using 8-13 Hz imaginary inter-site phase coherence in the frontoparietal networks (Fz-P3 and Fz-P4) and the motor cortex-sensorimotor networks (Cz-C3 and Cz-C4) during a golf putting task. To gain a deeper understanding of the dynamic nature of learning trajectories, we compared data at three time points: baseline (T1), 50% improvement from baseline (T2), and 100% improvement from baseline (T3). The results primarily focused on EG, an inverted U-shaped coherence curve was observed in the connectivity of the left motor cortex-sensorimotor circuit, whereas an increase in the connectivity of the right frontoparietal circuit from T2 to T3 was revealed. These results imply that the dynamics of cortico-cortical communication, particularly involving the left motor cortex-sensorimotor and frontal-left parietal circuits. In addition, our findings partially support Hikosaka etal.'s model and provide additional insight into the specific role of these circuits in visuomotor learning.

High-fat diet effects on contractile performance of isolated mouse soleus and extensor digitorum longus when supplemented with high dose vitamin D.

Evidence suggests vitamin D3 (VD) supplementation can reduce accumulation of adipose tissue and inflammation and promote myogenesis in obese individuals, and thus could mitigate obesity-induced reductions in skeletal muscle (SkM) contractility. However, this is yet to be directly investigated. This study, using the work-loop technique, examined effects of VD (cholecalciferol) supplementation on isolated SkM contractility. Female mice (n = 37) consumed standard low-fat diet (SLD) or high-fat diet (HFD), with or without VD (20,000IU/kg-1 ) for 12weeks. Soleus and EDL (n = 8-10 per muscle per group) were isolated and absolute and normalized (to muscle size and body mass) isometric force and power output (PO) were measured, and fatigue resistance determined. Absolute and normalized isometric force and PO of soleus were unaffected by diet (P>0.087). However, PO normalized to body mass was reduced in HFD groups (P<0.001). Isometric force of extensor digitorum longus (EDL) was unaffected by diet (P>0.588). HFD reduced EDL isometric stress (P=0.048) and absolute and normalized PO (P<0.031), but there was no effect of VD (P>0.493). Cumulative work during fatiguing contractions was lower in HFD groups (P<0.043), but rate of fatigue was unaffected (P>0.060). This study uniquely demonstrated that high-dose VD had limited effects on SkM contractility and did not offset demonstrated adverse effects of HFD. However, small and moderate effect sizes suggest improvement in EDL muscle performance and animal morphology in HFD VD groups. Given effect sizes observed, coupled with proposed inverted U-shaped dose-effect curve, future investigations are needed to determine dose/duration specific responses to VD, which may culminate in improved function of HFD SkM.

The associations of erythrocyte membrane polyunsaturated fatty acids with skeletal muscle loss: A prospective cohort study

Polyunsaturated fatty acids (PUFAs) may play a vital role in maintaining skeletal muscle mass in the aged population. This study investigated the longitudinal relationship between the concentrations of erythrocyte membrane PUFAs and age-related changes in skeletal muscle mass over an average 6.5 years of follow-up in a Chinese middle-aged and older adult population. A total of 1494 participants aged 57.4±4.7 years were included in this study. Skeletal muscle mass was determined using dual-energy X-ray absorptiometry. Per year percent changes in the skeletal muscle index (Δ% SMI), appendicular skeletal muscle index (Δ% ASMI), and total body lean mass index (Δ% TBLMI) from baseline were calculated. Concentrations of total and individual cis-n-3 and cis-n-6 PUFAs of the erythrocyte membrane were determined using gas-liquid chromatography. Fully adjusted linear regression models showed that per unit increases in the concentrations of C18:2 n-6, C20:4 n-6, C22:4 n-6, and total n-6 PUFAs resulted in increases of 0.022%-0.155% in the Δ% SMI (P for linearity: <0.001-0.006). Restricted cubic spline analysis revealed an inverted U-shaped relationship between the concentrations of C20:2 n-6, C22:5 n-3, C22:6 n-3, and total n-3 PUFAs and the Δ% SMI (P for non-linearity: <0.001-0.036). In addition, an inverted U-shaped curve was also detected for the relationships of the linoleic acid/α-linolenic acid ratio (P for non-linearity=0.010) and n-6/n-3 PUFA ratio (P for non-linearity=0.013) with the Δ% SMI, with the Δ% SMI peaking at respective ratios of 124.96 and 3.69. Similar associations were revealed by the Bayesian kernel machine regression model. No interaction effect was detected between the individual PUFAs for the Δ% SMI in the bivariate exposure-response analysis. Overall, similar results were observed for the Δ% ASMI and Δ% TBLMI. The associations between different individual PUFAs and age-related muscle loss in middle-aged and older adults may be different. Our results suggest that high concentrations of erythrocyte membrane n-6 PUFAs may be correlated with less skeletal muscle mass loss, whereas extremely high concentrations of n-3 PUFAs may be correlated with more muscle loss.

Urban Comprehensive Carrying Capacity and Urbanization in Northeast China

The scientific evaluation and identification of the relationship between urban comprehensive carrying capacity and urbanization in Northeast China, a famous old industrial base, is an important basis for realizing the overall revitalization of the region. Using a panel data set of 34 prefecture-level cities in Northeast China from 2003 to 2019, this study constructs an ordinary panel data model to identify the relationship between urban comprehensive carrying capacity and urbanization. The results show that urbanization has significantly positive effects on urban comprehensive carrying capacity, and there is a significant inverted U-shaped curve relationship between urban comprehensive carrying capacity and comprehensive urbanization in Northeast China, especially in the shrinking cites. In addition, the economic urbanization variables of the fixed-asset investment, the total retail sales of social consumer goods, and the social urbanization variable of internet users play significantly important roles in forming of the inverted U-shaped curve relationship with the urban comprehensive carrying capacity of the shrinking cities in Northeast China. Hence, innovation-driven economic regrowth, promoting equalization of basic public services, alleviating talent outflow, and strengthening the leading roles of the core cities are effective measures for improving urban comprehensive carrying capacity and urbanization quality in Northeast China.

Do vertical ecological compensation policies promote green economic development: A case study of the transfer payments policy for China’s National Key Ecological Function Zones

The transfer payment policy for National Key Ecological Function Zones is a typical vertical ecological compensation (VEC) policy that has been in place in China since 2008. This study treats this VEC policy as a quasi-natural experiment and utilises a slack-based measure model to calculate each county’s green economic efficiency based on China’s county-level data for the period 2003–2020. Then, the difference-in-differences method is used to evaluate the impact of the VEC policy on green economic efficiency and to verify its possible mechanisms. The results indicate that the VEC policy significantly improves the green economic efficiency of compensated areas, demonstrating that this policy promotes regional green economic development. Moreover, we find that the VEC policy may improve green economic efficiency by reducing the pollution caused by industrial development, promoting eco-industrial development and accelerating technological innovation. From the perspective of realising its three policy goals, the VEC policy not only improves the compensated areas’ ecological environment quality, but also promotes economic growth and optimises public services in the compensated areas. Furthermore, an inverted U-shaped curve relationship between the scale of VEC and green economic efficiency is identified.

Trends in use of proton pump inhibitors among adults in the United States from 1999 to 2018.

Proton pump inhibitors (PPIs) are among the most commonly used drugs in the United States (U.S.). We aimed to determine the trends in use of PPIs among adults in the U.S. from 1999 through 2018, hypothesizing the trend would follow an inverted U-shaped curve, with a decline in recent years due to safety concerns. Temporal trends in use of prescription PPIs were assessed using the 1999-2018 National Health and Nutrition Examination Survey (NHANES), a nationally representative cross-sectional survey of non-institutionalized U.S. civilians. Use of PPIs was defined as any use during the month preceding the survey. Descriptive statistics were produced and trends in PPI use were examined, stratified by sex, age, race, body mass index (BMI), and poverty level. Use of prescription PPIs increased from 4.1% of U.S. adults in 1999-2000 to 8.6% in 2017-2018 (p for trend <0.01). All of the increase was observed during the first half of the study period (4.6% increase from 1999 to 2008 vs. 0.5% decrease from 2009 to 2018) and almost all of it was among those aged 55 or more (8.6% increase among those aged ≥ 55 compared to 1.2% increase among those aged < 55, p for interaction based on age <0.01). Use of prescription PPIs increased from 1999 to 2008 and then plateaued through 2018. This rise was driven by increased usage among older NHANES respondents.

Association between the Weight-Adjusted Waist Index and Serum Uric Acid: A Cross-Sectional Study.

Serum uric acid (SUA) was closely related to body metabolism. This study aimed to investigate the relationship between the adult weight-adjusted waist index (WWI) and SUA. In the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2020, 6494 eligible participants aged ≥20 were included. The multivariate logistic regression model was used to test the correlation between WWI and SUA. At the same time, subgroup analysis was carried out by using multivariate logistic regression according to age, sex, and race. Then, the fitting smooth curve was applied to solve the association between WWI and SUA. Finally, the recursive algorithm was used to calculate the inflection point in the nonlinear relationship, and the two-stage piecewise linear regression model was used to analyze the relationship between WWI and SUA on both sides of the inflection point. In all the 6494 participants, through the fully adjusted model, this study found that there was a positive correlation between WWI and SUA (β = 5.64; 95% CI: 2.62 and 8.66). In addition, this positive correlation still had certain statistical significance in the subgroup analysis stratified by sex, age, and race. Our research team found a significant positive correlation between the WWI and SUA in females, but the correlation was not significant in males. We also found a small inverted U-shaped curve between the WWI and SUA in men when we stratified the sex subgroups. The small inflection point was determined to be 11.5 cm/√ kg. In racial subgroup analysis, we also found a U-shaped relationship between the WWI and SUA in non-Hispanic White and other race/ethnicity (the inflection point was 11.08 cm/√ kg and 12.14 cm/√ kg, respectively). This study showed that the WWI was a newly developed and new predictor of centripetal obesity independent of body weight and there was a positive correlation between the WWI and SUA.

What drives income inequality? Bayesian evidence from the emerging market economies

ABSTRACT What drives income inequality in emerging market economies? To end it, we approach this topic utilizing Bayesian model averaging and 27 emerging market economies panel dataset from 1990 to 2019. First, differently, we find a U-shaped Kuznets curve in emerging market economies rather than the notable inverted U-shaped curve. Besides, we find four strictly robust determinants of income inequality in emerging market economies, including the population aging, the female labor force participation, the unemployment level and the share of labor compensation in output. These results remain stable through a series of robustness checks. In most cases, the government expenditure and real exchange rate could also robustly drive the dynamics of income inequality in emerging market economies. Further, a comparative analysis suggests that financial development, inflation, human capital condition, total factor productivity and urbanization are distinct determinants of income inequality in the market economies.

Unleashing the nexus among urban land use, national physical health inputs and environment: an environmental sustainability paradigm.

Nowadays, the contemporary ecological environment has a significant impact on human survival and development. Consequently, an in-depth examination of the link between humans and nature has significant practical significance and aspirational appeal. This research analyzes provincial panel data from 2011 to 2019 using an empirical model to determine the relationship between urban land use, the ecological environment, and national physical health inputs in China. The results indicate that (1) urbanization and air pollution do not have an "inverted U-shaped" traditional environmental Kuznets curve relationship, but rather a significant "positive U" relationship; (2) urbanization and environmental management do have an inverted U-shaped classical environmental Kuznets curve relationship; (3) GDP per capita and infrastructure have a negative impact on air quality and environmental quality, and strict environmental rules can improve air quality and green amenities; (4) national physical health investment has a substantial moderating effect on the relationship between urban land use and the ecological environment.