U-shaped Curve Research Articles

Prevalence, Awareness, Treatment, and Control of Type 2 Diabetes in South Korea (1998 to 2022): Nationwide Cross-Sectional Study.

Type 2 diabetes poses an increasing disease burden in South Korea. The development and management of type 2 diabetes are closely related to lifestyle and socioeconomic factors, which have undergone substantial changes over the past few decades, including during the COVID-19 pandemic. This study aimed to investigate long-term trends in type 2 diabetes prevalence, awareness, treatment, and control. It also aimed to determine whether there were substantial alterations in the trends during the pandemic and whether these changes were more pronounced within specific demographic groups. This study examined the prevalence, awareness, treatment, and control of type 2 diabetes in a representative sample of 139,786 South Koreans aged >30 years, using data from the National Health and Nutrition Examination Survey and covering the period from 1998 to 2022. Weighted linear regression and binary logistic regression were performed to calculate weighted β coefficients or odds ratios. Stratified analyses were performed based on sex, age, region of residence, obesity status, educational background, household income, and smoking status. β (difference) was calculated to analyze the trend difference between the prepandemic period and the COVID-19 pandemic. To identify groups more susceptible to type 2 diabetes, we estimated interaction terms for each factor and calculated weighted odds ratios. From 1998 to 2022, a consistent increase in the prevalence of type 2 diabetes was observed among South Koreans, with a notable rise to 15.61% (95% CI 14.83-16.38) during the pandemic. Awareness followed a U-shaped curve, bottoming out at 64.37% (95% CI 61.79-66.96) from 2013 to 2015 before increasing to 72.56% (95% CI 70.39-74.72) during the pandemic. Treatment also increased over time, peaking at 68.33% (95% CI 65.95-70.71) during the pandemic. Control among participants with diabetes showed no substantial change, maintaining a rate of 29.14% (95% CI 26.82-31.47) from 2020 to 2022, while control among treated participants improved to 30.68% (95% CI 27.88-33.48). During the pandemic, there was a steepening of the curves for awareness and treatment. However, while the slope of control among participants being treated increased, the slope of control among participants with diabetes showed no substantial change during the pandemic. Older populations and individuals with lower educational level exhibited less improvement in awareness and control trends than younger populations and more educated individuals. People with lower income experienced a deceleration in prevalence during the pandemic. Over the recent decade, there has been an increase in type 2 diabetes prevalence, awareness, treatment, and control. During the pandemic, a steeper increase in awareness, treatment, and control among participants being treated was observed. However, there were heterogeneous changes across different population groups, underscoring the need for targeted interventions to address disparities and improve diabetes management for susceptible populations.

Optimizing Defibrillator Deployment with Bus-Mounted Automated External Defibrillator

Objectives Early defibrillation with an automated external defibrillator (AED) can effectively improve the survival rate of patients with out-of-hospital cardiac arrest (OHCA). Placing AEDs in public locations can reduce the defibrillation response interval from collapse to defibrillation. Most public AEDs are currently placed in a stationary way (S-AED) with limited coverage area. Bus mounted AED (B-AED) can be delivered directly to the demand point. Although B-AEDs are only available during bus operating hours, they provide greater coverage area. When the number of available AEDs is insufficient, better coverage may be achieved by placing a portion of AEDs as B-AEDs. Our purpose is developing a model to determine the optimal locations of B-AEDs and S-AEDs with a predetermined number of available AEDs. The goal is to maximize the total coverage level of all demand points. Methods We proposed a joint location model to place B-AEDs and S-AEDs based on the p-median problem (JPMP). Using data from Chang’an District, Xi’an City, China, we determined the optimal AED deployment. The performance of JPMP was compared with several other models. The coverage results of JPMP are analyzed in details, including the quantity assignment, coverage level, and geographical location of B-AEDs and S-AEDs. The impact of the bus departure intervals on coverage was also discussed. Results The use of B-AEDs results in an average 98.43% increase in the number of covered demand points, and an average 74.05% increase in total coverage level. In optimal AED deployment, B-AEDs coverage follows an inverted U-shaped curve with increasing number of available AEDs. It begins to decrease when all demand points during the operating hours are covered. With a constant number of available AEDs, the total coverage level increases and then decreases as the bus departure interval increases. The larger the number of available AEDs, the smaller the optimal departure interval. Conclusions With a given number of available AEDs, combinational deployment of B-AEDs and S-AEDs significantly improves the coverage level. B-AEDs are recommended when AEDs are insufficient. If more AEDs are available, better coverage can be obtained with reasonable location of S-AEDs and B-AEDs.

Looking back on a gold standard: a systematic literature review of laparoscopic Nissen fundoplication as an anti-reflux treatment option

Summary Background Laparoscopic Nissen fundoplication is considered the gold standard in surgical management of gastroesophageal reflux disease. Therefore, exhaustive scrutiny of the procedure is necessary. The aim of this study was to perform a complete and systematic literature review of laparoscopic Nissen fundoplication to summarize the evidence for safety and efficacy over time. Methods MEDLINE, Embase, CINAHL, the Cochrane Library, and Web of Science were searched for randomized controlled trials investigating intra- and postoperative outcomes at follow-ups between 4–6 weeks and 17 years. Results Among 1675 screened articles, 63 articles were identified comprising 40 trials with a total of 2619 participants. Intraoperative events included bleeding (2.9%), gastroesophageal injury/perforation (0.9%), and spleen injury/splenectomy (0.9%). One-year clinical follow-up presented the following: dysphagia (22.4%), heartburn or epigastric/sternal pain (15.1%), gas bloating (30.1%), and inability to vomit/belch (16.4%). These outcomes displayed a U-shaped curve with a minimum of symptoms at 1 year. At 10 years postoperatively, clinical outcomes deteriorated, demonstrating dysphagia (45.3%), heartburn or epigastric/sternal pain (30.9%), inability to vomit/belch (48.8%), and gas bloating (44.4%). Furthermore, the surgical benefit seems to dissipate at 17 years. At 1 and 10 years after surgery, reoperation rates were 6.7% and 16.3%, whereas proton pump inhibitor (PPI) use was at 12.3% and 23.3%, respectively. Conclusion The performance of Nissen fundoplication declines over time, as demonstrated by increased PPI medication usage for recurrent symptoms and an increased reoperation rate reaching a combined 39.6%, representing failures after 10 years. The complication rates are dominated by dysphagia, gas bloating, inability to belch/vomit, and/or recurrent reflux symptoms with heartburn.

Elevated ALT/AST ratio as a marker for NAFLD risk and severity: insights from a cross-sectional analysis in the United States.

The prevalence and incidence of Nonalcoholic fatty liver disease (NAFLD) are increasing worldwide, and NAFLD has emerged as a prominent global health concern. The link between serum alanine aminotransferase (ALT) to aspartate aminotransferase (AST) ratio and NAFLD remains unclear. This study investigated the association between the ALT/AST ratio and NAFLD prevalence, including liver steatosis and fibrosis levels in the population. We conducted a cross-sectional study using data from the National Health and Nutrition Examination Survey (NHANES) 2017-2018, including 4753 participants. Subgroup analyses, stratified by age, gender, and body mass index (BMI), were performed, along with adjusted multivariable logistic regression analyses to evaluate the relationship between ALT/AST levels and the likelihood of NAFLD, liver steatosis, and hepatic fibrosis stage. A generalized additive model examined the non-linear relationship between ALT/AST and the probability of developing NAFLD. Among 4753 participants, 1508 (31.73%) were diagnosed with NAFLD. Significant positive correlations between ALT/AST and NAFLD risk were found across all models. In addition, the subgroup analysis by gender, age, and BMI suggested that ALT/AST showed a positive correlation with NAFLD. The ALT/AST ratio was positively correlated with the degree of liver steatosis and liver fibrosis. The correlation between ALT/AST and the incidence of NAFLD showed a non-linear pattern. In women, the non-linear trend is particularly evident, showing an inverted U-shaped curve with an inflection point of 1.302.A receiver operating characteristic (ROC) analysis showed that the predictive value of ALT/AST for NAFLD was better than that of traditional liver enzyme parameters. A higher ALT/AST ratio was independently associated with a significantly higher risk of NAFLD and liver fibrosis within American cohorts. This link is robust among females, children, and adolescents. ALT/AST ratio can be used as a simple and effective noninvasive biomarker to identify individuals with high risk of NAFLD.

Gender differences in the relationship between nicotine exposure and symptoms of depression

BackgroundTobacco-derived nicotine exposure is linked to depression. However, the associations of nicotine and its metabolites with symptoms of depression, particularly concerning gender differences, remain underexplored. MethodsThe characteristics and total nicotine equivalents (TNE) of 1001 subjects were determined. The association between the TNE and symptoms of depression, accounting for gender differences, was investigated using generalized linear models and subgroup analyses. ResultsMen exhibited significantly greater levels of the nicotine exposure indicators TNE2, TNE3, TNE6, and TNE7 (P < 0.005). A significantly greater percentage of women (23.45 %) than men (9.81 %) exhibited symptoms of depression (P < 0.0001). In women, the relationship between the TNE and depression was reflected by a U-shaped curve with significant inflection points, particularly for TNE3, TNE6, and TNE7. Furthermore, in women, concentrations above 48.98 nmol/mL for TNE3, 53.70 nmol/mL for TNE6, and 57.54 nmol/mL for TNE7 were associated with 154 %, 145 %, and 138 % increases in the risk of depression, respectively. In contrast, these associations did not reach significance among men. LimitationsThe cross-sectional design limits the ability to infer causality between nicotine exposure and depressive symptoms. Larger-scale studies are needed to confirm these findings. ConclusionsGender could be a significant factor influencing the relationship between nicotine exposure levels and symptoms of depression. The impact of nicotine exposure on symptoms of depression should be particularly considered among women. ImplicationsThis study revealed the complex relationship between tobacco-related nicotine exposure and depressive symptoms, with a particular focus on gender differences. Our results revealed a distinct U-shaped correlation between total nicotine equivalents and depression in women, which differed from that in men. These findings emphasize the importance of tailoring clinical approaches to address nicotine exposure and manage depressive symptoms based on gender.

Unhealthy weight control behaviors and health risk behaviors in American youth: a repeated cross-sectional study

BackgroundUnhealthy weight control behaviors (UWCBs) involve weight control strategies to reduce or maintain weight, such as fasting, taking diet pills, and vomiting or taking laxatives. UWCBs in teenagers can escalate into severe health issues such as eating disorders. Understanding the trends of UWCBs and their association with risk behaviors in teenagers is crucial, as early intervention and prevention strategies are pivotal.MethodsThis study utilized eight waves of the youth risk behavior surveillance system (YRBSS) data from 1999 to 2013. Our primary outcome was UWCBs engagement. We used multinomial logistic models to analyze the association between UWCBs and risk behaviors among adolescents including driving after alcohol consumption, suicide attempts, smoking, alcohol use, and sexual intercourse.ResultsAmong 109,023 participants, UWCBs prevalence was 16.64%. Body Mass Index (BMI) was significantly associated with UWCBs risk. In addition, we found the intention of weight management confounded the relationship between BMI and UWCBs. The unadjusted logistic regression indicated a monotone-increasing association between BMI and the risk of UWCBs. In contrast, the adjusted logistic regression indicated a U-shaped curve with the lowest (BMI < 17 kg/m2) and highest (BMI > 30 kg/m2) BMI groups having significantly higher odds of engaging in UWCBs compared to the reference BMI group (18.5 ≤ BMI ≤ 24.9 kg/m2).ConclusionsThe intention of weight management confounded the relationship between Body Mass Index (BMI) and the risk of UWCBs. These findings suggest that healthcare interventions for weight management behaviors should be tailored to adolescents with BMI ≥ 25 and BMI < 18.5.

Auditory Noise Facilitates Lower Visual Reaction Times in Humans.

Noise is commonly seen as a disturbance but can influence any system it interacts with. This influence may not always be desirable, but sometimes it can improve the system's performance. For example, stochastic resonance is a phenomenon where adding the right amount of noise to a weak signal makes it easier to detect. This is known as sub-threshold detection. This sub-threshold detection's natural fingerprint is the fact that the threshold values follow an inverse U-shaped curve as the noise intensity increases. The minimum threshold value is the point of maximum sensitivity and represents the optimal point that divides the dynamics in two. Below that point, we can find the beneficial noise branch, where the noise can facilitate better detection. Above that point, the common detrimental noise concept can be found: adding noise hinders signal detection. The nervous system controls the movements and bodily functions in the human body. By reducing the sensory thresholds, we can improve the balance of these functions. Additionally, researchers have wondered if noise could be applied to different senses or motor mechanisms to enhance our abilities. In this work, noise is used to improve human reaction times. We tested the hypothesis that visual reaction times decrease significantly when the subject's perception is in the beneficial noise branch and closer to the optimal point than outside of this condition. Auditory noise was introduced in 101 human subjects using an interface capable of searching for the right amount of noise to place the subject in the beneficial noise branch close to the optimal point. When comparing the results, the reaction times decreased when the subjects were at the optimal point compared to when the subjects were outside of such conditions. These results reveal the possibility of using this approach to enhance human performance in tasks requiring faster reaction times, such as sports.

2243 Modification effect of disability profiles on the association of blood pressure and mortality among older long-term care people

Abstract Introduction Evidence of the optimal blood pressure target for older people with disability in long-term care is limited. We aim to estimate the associations of blood pressure with all-cause and cause-specific mortality in older people with different profiles of disability. Methods This prospective cohort study was based on the government-led long-term care program in Chengdu, China, including 41,004 consecutive disabled adults aged ≥60 years. The association between blood pressure and mortality was analysed with doubly robust estimation, which combined exposure model by inverse probability weighting and outcome model fitted with Cox regression. The non-linearity was examined by restricted cubic spline. The primary endpoint was all-cause mortality, and the secondary endpoints were cardiovascular and non-cardiovascular mortality. Results The associations between systolic blood pressure (SBP) and all-cause mortality were close to a U-shaped curve in mild–moderate disability group (Barthel index ≥40), and a reversed J-shaped in severe disability group (Barthel index &amp;lt;40). In mild–moderate disability group, SBP &amp;lt; 135 mmHg was associated with elevated all-cause mortality risks (HR 1.21, 95% CI, 1.10–1.33), compared to SBP between 135–150 mmHg. In severe disability group, SBP &amp;lt;150 mmHg increased all-cause mortality risks (HR 1.21, 95% CI, 1.16–1.27), compared to SBP between 150–170 mmHg. The associations were robust in subgroup analyses in terms of age, cardiovascular comorbidity and antihypertensive treatment. Diastolic blood pressure (DBP) &amp;lt; 67 mmHg (HR 1.29, 95% CI, 1.18–1.42) in mild–moderate disability group and &amp;lt; 79 mmHg (HR 1.15, 95% CI, 1.11–1.20) in severe disability group both demonstrated an increased all-cause mortality risk. Conclusion The optimal blood pressure range was higher in older long-term care people with severe disability than those with mild–moderate disability. This study provides new evidence for optimal individualised management of blood pressure in disabled older people in long-term care settings.

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.

Are cities under bright lights more innovative? Evidence from China

The prosperity of the nighttime economy is an important criterion for measuring urban development. Based on regression analysis of data from 330 prefecture-level cities in China, this study explores the potential link between urban lighting and urban innovation capacity. The results show that the relationship between nighttime light intensity and urban innovation capacity follows an inverted U-shaped curve. Moreover, urban nighttime light stability moderates the above relationship. In addition, the heterogeneity analysis indicates that low population density, weak economic foundation, and high administrative grade weaken the relationship between lighting intensity and urban innovation capacity. Finally, the mechanism analysis suggested that the inverted U-shaped relationship between urban lighting and innovation capacity may be caused by the encroachment of the service industry and the loss of urban attractiveness. By exploring the proxy effect of nighttime lighting on urban innovation, this study reveals the imbalance between extrinsic image and the intrinsic capacity of cities, which not only extends the research on urban construction and development but also provides guidance for local governments concerning how to achieve all-round coordination of cities.

Historical Performance Gap, Readiness of Government, and Open Data Quality: Transnational Empirical Analysis Based on Performance Feedback Theory

Open government data has become an important movement for government administrations in numerous countries. Previous studies have paid less attention to the complex relationship among the historical performance gap, the readiness of government (including policy and action dimensions), and open data quality. Therefore, on the basis of performance feedback theory, a theoretical model has been developed and tested to analyze the impact of the historical performance gap on the readiness of government and open data quality. The model is empirically tested by the partial least squares method using sample data from 115 countries. The results show that the historical performance gap could indirectly contribute to a country's open data quality by promoting the readiness of government. In addition, the impact of this gap on the readiness of government and open data quality shows a U-shaped curve. In other words, a greater change in the effect of open data utilization in a country in the previous year entails a more significant promotion of readiness of government and open data quality in the next year. These findings drive governments to pay more attention to performance evaluation in open data and improve the readiness of government to improve their respective country's open data quality.

Molecular Pathway Changes Associated with Different Post-Conditioning Exercise Interventions After Experimental TBI.

Traumatic brain injury (TBI) causes complex, time-dependent molecular and cellular responses, which include adaptive changes that promote repair and recovery, as well as maladaptive processes such as chronic inflammation that contribute to chronic neurodegeneration and neurological dysfunction. Hormesis is a well-established biological phenomenon in which exposure to low-dose toxins or stressors results in protective responses to subsequent higher-level stressors or insults. Hormetic stimuli show a characteristic U-shaped or inverted J-shaped dose-response curve, as well as being time and exposure-frequency dependent, similar to pre-conditioning and post-conditioning actions. Voluntary exercise interventions, before or after injury, appear to follow these general hormetic principles. But the molecular alterations associated with exercise interventions or more general hormetic responses have received only limited attention. In this study, we used a well-characterized mouse TBI model to assess the effects of different post-conditioning exercise-intervention paradigms on diverse molecular pathways, including neuroinflammation regulators, and post-traumatic neurological deficits. We generated high-throughput gene expression data and associated molecular pathway analyses to assess the potential molecular mechanisms associated with time- and duration-dependent voluntary exercise intervention, as well as time after treatment. Importantly, we also used newer analytical methods to more broadly assess the impact of exercise on diverse molecular pathways. TBI caused long-term changes in multiple neuroinflammation markers and chronic cognitive dysfunction. Notably, all delayed, post-conditioning exercise interventions reduced post-traumatic neuroinflammation and/or attenuated the related cognitive changes, albeit with different pathway specificity and effects magnitude. Exercise comprehensively reversed injury-associated effects in the hippocampus across both activated inflammatory and inhibited neuronal pathways, consistent with a return toward the noninjured, homeostatic state. In contrast, the cortex showed a less consistent pattern with more limited attenuation of inflammatory pathway activation and an amplification in the injury-dependent inhibition of select noninflammatory pathways, indicating less effective and potentially detrimental responses to exercise. Exercise intervention beginning 2 weeks after injury and lasting 2 weeks was less effective than exercise continuing for 4 weeks. Exercise initiated at a more delayed timepoint of 6 weeks after injury and continuing for 4 weeks was more effective than that during the acute phase. The delayed paradigm was also more effective than exercise initiated at 10 weeks after injury and continuing for 8 weeks, consistent with hormetic responses in other models and species. Overall, our study delineates regional and interventional parameters, as well as related molecular pathway changes, associated with post-conditioning exercise treatment, which may help inform future translational interventional strategies.

Scenario analysis of the Indonesia carbon tax impact on carbon emissions using system dynamics modeling and STIRPAT model

This study aims to develop a system dynamic (SD) forecasting model based on the STIRPAT model to forecast the effect of an IDR 30 per kg CO2e carbon tax on carbon emissions, estimate future carbon emissions under ten scenarios, without and with the carbon tax, and estimate the environmental Kuznets curve (EKC) to predict Indonesia’s carbon emission peak. Carbon emission drivers in this study are decomposed into several factors, namely energy structure, energy intensity, industrial structure, GDP per capita, population, and fixed-asset investment. This study included nuclear power utilization starting in 2038. The research gaps addressed by this study compared to previous research are (1) use of the ex-ante approach, (2) inclusion of nuclear power plants, (3) testing the EKC hypothesis, and (4) contribution to government policy. The simulation results show that under the carbon tax, carbon emissions can be reduced by improving renewable energy structures, adjusting industrial structures to green businesses, and emphasizing fixed asset investment more environmentally friendly. Moreover, the result approved the EKC hypothesis. It shows an inverse U-shaped curve between GDP per capita and CO2 emissions in Indonesia. Indonesia’s fastest carbon emission peak is under scenario seven and is expected in 2040. Although an IDR 30 per kg CO2e carbon tax and nuclear power will take decades to reduce carbon emissions, the carbon tax can still be a reference and has advantages to implement. This result can be a good beginning step for Indonesia, which has yet to gain experience with a carbon tax that can be implemented immediately and is helpful to decision-makers in putting into practice sensible measures to attain Indonesia’s carbon emission peaking. This research provides actionable insights internationally on carbon tax policies, nuclear energy adoption, EKC dynamics, global policy implications, and fostering international cooperation for carbon emission reductions.

Unveiling the dynamics of urbanization and ecosystem services: insights from the Su-Xi-Chang Region, China

Assessing the impact of past and future urban land expansion on ecosystem services (ESs) is essential for the sustainable management of urban landscapes. Despite recent progress, it remains challenging to determine the influence mechanism of different urbanization stages and areas on ESs and their trade-offs/synergies. Here, we analyzed the responses of four ESs and their trade-offs/synergies to the spatial and temporal differentiation of urbanization in the Su-Xi-Chang region of China from 1990 to 2050. The results showed that the relationship between ESs and urbanization followed a U-shaped curve from 1990 to 2050. Between 1990 and 2020, urbanization weakened trade-offs and enhanced lose-lose situations, exhibiting an S-shaped curve. From 2020 to 2050, lose-lose situations are expected to diminish, and the curve is projected to display a downward trend. Our findings suggest the implementation of compact urban development, sustainable agricultural practices, reforestation, and the conversion of farmland to lakes.

Linkages between digital economy and ecosystem services: Revealing the spatiotemporal relationship based on U-shaped effect

This study employs geographically and temporally weighted regression and spatial Durbin models to investigate the impact of digital economy index (DEI) on ecosystem service value (ESV). Estimates of DEI are obtained from night-time light data, and ESV is assessed by the equivalent factor method. The findings indicate significant spatial agglomeration of both DEI and ESV in China. Overall, the impact of DEI on ESV exhibits a U-shaped effect: initially restrained, then promoted. Moreover, the analysis detects spatiotemporal heterogeneity in the DEI-ESV interaction. Spatially, higher DEI positively impacts lower ESV in eastern China, while lower DEI negatively impacts higher ESV in western China. Temporally, most cities in eastern China, unlike those in western China, surpassed the U-shaped curve's inflection point during the study period. Furthermore, the number of cities exceeding the inflection point has increased, amplifying the dual positive and negative impacts of DEI on ESV over time. By revealing the multi-staged and geographically diverse impact of DEI on ESV, this study helps to address the environmental sustainability challenges posed by the rapid advancement of digital technologies.

Renewable Energy, Economic Policy Uncertainty and Climate Policy Uncertainty: New Evidence for Environmental Kuznets Curve from Emerging and Developed Countries

Recent events, such as the financial crisis, oil price shocks or fluctuations, Brexit, the US–China trade war, the COVID-19 pandemic, the Russia–Ukraine conflict and the subsequent energy crisis, have surged global economic policy uncertainty. As climate change has recently been more pronounced around the globe, discussions about climate policies and related uncertainties have also become a major concern. This study investigates the role of economic policy uncertainty (EPU) and climate policy uncertainty (CPU) on climate change (environmental degradation) for selected emerging and developed economies, expanding the IPAT framework and merging it with the Environmental Kuznets Curve (EKC) hypothesis. The IPAT framework examines the impact (I) of population (P), affluence (A), and technology (T) on the environment, whereas the EKC hypothesis proposes an inverted U-shaped curve between affluence and environmental degradation. Two models were created and tested for emerging and developed countries, namely Model 1 with EPU and Model 2 with CPU. A Pooled Mean Group (PMG) estimator is employed to investigate the interrelation between carbon dioxide (CO2) emissions and selected variables; namely the real Gross Domestic Product (GDP) per capita, squared real GDP per capita, renewable share in consumption, the EPU, the CPU and population. Test results indicate that the EKC hypothesis is verified only in Model 1 and for emerging countries, whereas population escalates climate change in both country groups. Furthermore, in line with the consumption effect theorized earlier in the literature, EPU is negatively related to carbon emissions in emerging countries. Thus, the EPU leads to a decrease in the use of energy and pollution-intensive commodities and mitigates climate change in EMEs. Compatible with our ex-ante expectations, renewable energy consumption alleviates climate change in both country groups in the short term. In Model 2, with CPU, we find no evidence supporting the EKC hypothesis for any country groups. However, we reaffirm that renewable energy consumption decreases CO2 emissions in developed countries, which is in support of the argument that energy transition holds the key to tackling climate change. Finally, CPU is associated with a decrease in CO2 emissions in emerging countries in the short term, potentially leading to a reduction in overall economic activity and alleviating climate change. This might also be attributable to the fact that the decisions of economic agents substantially rely on current and future policy (both economic and climate) expectations. Overall, verifying the EKC hypothesis for emerging countries in Model 1, we might argue that there is good potential for emerging countries to save money and time on environmental costs via the adoption of clean technologies and related policies. Last but not least, on a global scale, energy transition with better utilization of renewable sources holds the key to tackling climate change and reducing emissions.

Response of Low Carbon Level to Transportation Efficiency in Megacities: A Case Study of Beijing, China

Global warming caused by massive carbon dioxide emissions can lead to a chain of ecological disasters. As one of the main sources of carbon emissions, transportation is of great significance, and the evaluation of its connections with carbon emissions is necessary to achieve “carbon neutrality”. Taking Beijing as an example, this study evaluated traffic efficiency (TE) by utilizing principal component analysis and fuzzy comprehensive evaluation. Using the Tapio decoupling model and coupling coordination degree model, the corresponding relationship between urban low carbon level (LCL) and TE was explored. The results showed the following: (1) The total carbon emission (CE) level exhibited fluctuating variation from increasing to decreasing. The carbon emission intensity (CEI) continued to slow down, and the rapid growth of population density played a key role in low-carbon development. (2) The traffic operations continually showed a positive trend in development. TE increased from a step-like to a slow shape, until it declined in 2020 due to the pandemic. (3) TE and LCL both developed from low coordination to an extreme level of coordination. Per capita carbon emission (CEP) and TE presented an inverted U-shaped curve; meanwhile, with increases in TE, the decline in CEI slowed. In addition, the weak decoupling of TE changed to become strong, due to CE and CEP, and maintained a strong decoupling state from CEI. (4) There is a necessity for the rational planning of land use for transportation infrastructure, the encouragement of a combination of public and private transportation, and the strengthening of the maintenance of the relative infrastructure and the management of traffic behaviors to attain a win–win situation. The results provide a reference for optimizing the traffic structure to achieve “carbon neutrality”.

The relationship between uric acid and bone mineral density in the intermediate stage of CKD 1–3

BackgroundSome studies have suggested that uric acid has antioxidant properties that can prevent bone loss, but the relationship between uric acid and bone mineral density is controversial. The aim of this study was to investigate the relationship between UA and BMD in patients with CKD stage 1–3.MethodsWe extracted 13,047 participants from the NHANES database, including 7342 male subjects and 5705 female subjects. Weighted multiple linear regression analysis was used to investigate the correlation between UA and BMD in patients with CKD stages 1–3.ResultsIn patients with CKD stage 1–3, UA was significantly correlated with BMD. In the male group, UA was positively associated with BMD (β, 7.94 [95%CI, 4.95, 10.94]). In the female group, there was a negative relationship between them (β, -5.33 [95%CI, -8.77, -1.89]). The relationship between UA and BMD in male group showed an inverted U-shaped curve, and UA was positively correlated before 6.1 mg/dl and negatively correlated after 6.1 mg/dl. The relationship was basically negative in the female group.ConclusionsFor the patients with CKD stage 1–3, the relationship between UA and BMD showed an inverted U-shaped curve in the males, while the relationship was largely negative in the females.

Directors tenure diversity and corporate sustainability performance: The non-linear evidence from Indonesia public listed companies

The primary objective of this study is to thoroughly investigate the association between director tenure diversity and corporate sustainability performance. This study utilizes a sample comprising 578 firm-year observations from non-financial companies listed on the Indonesia Stock Exchange. To test the hypothesis, the study employs the Ordinary Least Squares method, complemented by a series of endogeneity tests. This study reveals that the sustainability performance of corporations in Indonesia falls significantly short of satisfactory levels. Furthermore, the study indicates that there is a negative association between tenure diversity and sustainability performance, demonstrating a U-shaped curve pattern. To ensure the robustness of our findings, we performed additional analysis using coarsened exact matching and Heckman (1979) two-stage least square methodologies, confirming that the results remained consistent with those of the initial test. Intriguingly, our supplementary analyses also revealed an inverse association between tenure diversity in the boardroom and sustainability performance within companies. This study makes a significant contribution to the corporate governance literature by elucidating the inverse association between director tenure diversity and sustainability performance. In doing so, it enhances the originality and novelty of existing studies, particularly within the context of developing countries, such as Indonesia. This study exhibits novelty by embracing a quantitative approach to measure sustainability performance, revealing an intriguing inverse association between sustainability performance and ESG initiatives within the companies.

COVID-19 risk perception and food security in the MENA region: evidence from a multi-wave household survey

The COVID-19 pandemic had disruptive consequences for MENA countries’ agri-food value chains that exacerbated poverty and jeopardized food security. This study examines the relationship between individuals’ perception of contracting COVID-19 and their experience of food insecurity, using longitudinal data from the Combined COVID-19 MENA Monitor Household survey. It also investigates the underlying mechanisms of COVID-19 concerns and explores coping strategies employed by households to identify vulnerabilities in food security. The results provide compelling evidence of a strong association between individuals’ concern about the virus and various dimensions of food security, particularly reduced purchasing power and decreased meal frequency. Notably, this association follows an inverted U-shaped curve, with food insecurity initially increasing as worry grows, but declining after individuals contract the virus. High levels of concern were also linked to significant income decreases and worsening economic conditions. Moreover, individuals with higher concerns were more likely to rely on specific coping strategies, particularly spending savings and obtaining funds from relatives or friends. These findings underscore the need for government interventions during disease outbreaks and economic downturns to focus on alleviating individuals’ worry and fear to facilitate informed decision-making that minimizes food insecurity consequences. Additionally, the findings emphasize the need to strengthen social protection systems during public health and economic challenges to ensure food security for vulnerable populations.