Sampling Period Research Articles

The Effect of Military Expenditure on Economic Prosperity in Croatia

The objective of this study was to empirically evaluate the impact of military spending on the economic well-being of the Croatian economy. The objective of the study was as well to find out if military expenditure could bolster the economic growth. Croatia has been among the European nations with significant military expenditures over the past three decades. However, these expenses have substantially decreased due to successful peace initiatives and the country's accession to the European Union. Reflecting on Croatia's history, notably during the Croatian War of Independence, the government significantly augmented its military expenditures. The sample period of the study was for 40 years from 1981 to 2020. An applied econometrics methodology called the 2-Stage Least Squares with Instrumental Variables was utilised in the study. In the first stage, instrumental variables were used to instrument for the endogenous regressors. In the second stage, the predicted values obtained from the first stage were used as explanatory variables in the main regression equation. The study found that the effect of military expenditure on the economic prosperity of Croatia was positive and highly statistically significant. The study addressed an empirical gap in the literature by integrating distinctive characteristics into the model concerning the long-term relationship between Croatia's military expenditure and economic growth. These factors enhanced empirical accuracy and instilled confidence in the broader and diverse literature concerning military expenditure and economic growth. The implication of this study is that investing in the military provides an enabling environment for economic growth to increase.

Wild herbivores and cattle have differing effects on postfire herbaceous vegetation recovery in an African savanna.

Fire and herbivory have profound effects on vegetation in savanna ecosystems, but little is known about how different herbivore groups influence vegetation dynamics after fire. We assessed the separate and combined effects of herbivory by cattle and wild meso- and megaherbivores on postfire herbaceous vegetation cover, species richness, and species turnover in a savanna ecosystem in central Kenya. We measured these vegetation attributes for five sampling periods (from 2013 to 2017) in prescribed burns and unburned areas located within a series of replicated long-term herbivore exclosures that allow six different combinations of cattle and wild meso- and megaherbivores (elephants and giraffes). Vegetation cover (grasses, mainly) and species richness were initially reduced by burning but recovered by 15-27 months after fire, suggesting strong resilience to infrequent fire. However, the rates of recovery differed in plots accessible by different wild and domestic herbivore guilds. Wildlife (but not cattle) delayed postfire recovery of grasses, and the absence of wildlife (with or without cattle) delayed recovery of forbs. Herbivory by only cattle increased grass species richness in burned relative to unburned areas. Herbivory by cattle (with or without wildlife), however, reduced forb species richness in burned relative to unburned areas. Herbivory by wild ungulates (but not cattle) increased herbaceous species turnover in burned relative to unburned areas. Megaherbivores had negligible modifying effects on these results. This study demonstrates that savanna ecosystems are remarkably resilient to infrequent fires, but postfire grazing by cattle and wild mesoherbivores exerts different effects on recovery trajectories of herbaceous vegetation.

Long-read powered viral metagenomics in the oligotrophic Sargasso Sea

Dominant microorganisms of the Sargasso Sea are key drivers of the global carbon cycle. However, associated viruses that shape microbial community structure and function are not well characterised. Here, we combined short and long read sequencing to survey Sargasso Sea phage communities in virus- and cellular fractions at viral maximum (80 m) and mesopelagic (200 m) depths. We identified 2,301 Sargasso Sea phage populations from 186 genera. Over half of the phage populations identified here lacked representation in global ocean viral metagenomes, whilst 177 of the 186 identified genera lacked representation in genomic databases of phage isolates. Viral fraction and cell-associated viral communities were decoupled, indicating viral turnover occurred across periods longer than the sampling period of three days. Inclusion of long-read data was critical for capturing the breadth of viral diversity. Phage isolates that infect the dominant bacterial taxa Prochlorococcus and Pelagibacter, usually regarded as cosmopolitan and abundant, were poorly represented.

The effect of diversity on disease reverses from dilution to amplification in a 22-year biodiversity × N × CO2 experiment

Plant disease often increases with N, decreases with CO2, and increases as biodiversity is lost (i.e., the dilution effect). Additionally, all these factors can indirectly alter disease by changing host biomass and hence density-dependent disease transmission. Yet over long periods of time as communities undergo compositional changes, these biomass-mediated pathways might fade, intensify, or even reverse in direction. Using a field experiment that has manipulated N, CO2, and species richness for over 20 years, we compared severity of a specialist rust fungus (Puccinia andropogonis) on its grass host (Andropogon gerardii) shortly after the experiment began (1999) and twenty years later (2019). Between these two sampling periods, two decades apart, we found that disease severity consistently increased with N and decreased with CO2. However, the relationship between diversity and disease reversed from a dilution effect in 1999 (more severe disease in monocultures) to an amplification effect in 2019 (more severe disease in mixtures). The best explanation for this reversal centered on host density (i.e., aboveground biomass), which was initially highest in monoculture, but became highest in mixtures two decades later. Thus, the diversity-disease pattern reversed, but disease consistently increased with host biomass. These results highlight the consistency of N and CO2 as drivers of plant disease in the Anthropocene and emphasize the critical role of host biomass—despite potentially variable effects of diversity—for relationships between biodiversity and disease.

Navigating Real Estate Investment Trust Performance Dynamics: The Role of Style (Equity vs. Mortgage Real Estate Investment Trusts) and Diversification Amidst the COVID-19 Pandemic

In this paper, we investigate the impact of COVID-19 on different performance measures and the risk of US Real Estate Investment Trusts (REITs) with different styles. Our findings suggest a phenomenon with compelling evidence of reduced performance without any significant changes in risk profile amidst the COVID-19 pandemic. Particularly, mortgage REITs (MREITs) appear to be more adversely affected compared to equity REITs (EREITs). We further explore and analyze the performance of specialized REITs in contrast to diversified REITs in the distinctive conditions presented by COVID-19. We find that diversification creates value for the entire sample period, whereas, during the COVID-19 pandemic, property type specialization helps, although the results are weakly significant. The findings on risk suggest investors’ short-run outlook on market reaction. These results remain robust to additional tests. The implications provide insight for investors as a reference to reallocate assets in their portfolios during uncertain times.

Seasonality of submarine groundwater discharge to an Arctic coastal lagoon

AbstractSupra‐permafrost submarine groundwater discharge (SGD) in the Arctic is potentially important for coastal biogeochemistry and will likely increase over the coming decades owing to climate change. Despite this, land‐to‐ocean material fluxes via SGD in Arctic environments have seldom been quantified. This study used radium (Ra) isotopes to quantify SGD fluxes to an Arctic coastal lagoon (Simpson Lagoon, Alaska) during five sampling periods between 2021 and 2023. Using a Ra mass balance model, we found that the SGD water flux was substantial and dependent on environmental conditions. No measurable SGD was detected during the spring sampling period (June 2022), when the lagoon was partially ice‐covered. During ice‐free periods, the main driver of SGD in this location is wind‐driven lagoon water level changes, not tides, which control surface water recirculation through sediments along the lagoon boundary. A combination of wind strength and direction led to low SGD fluxes in July 2022, with an SGD flux of (6 ± 3) × 106 m3 d−1, moderate fluxes in August 2021 and July 2023, which had an average flux of (17 ± 9) × 106 m3 d−1, and high fluxes in October 2022, at (79 ± 16) × 106 m3 d−1. This work demonstrates how soil and environmental conditions in the Arctic impact Ra mobilization, laying a foundation for future SGD studies in the Arctic and shedding light on the major processes driving Ra fluxes in this important environment.

Social network dynamics, infant loss, and gut microbiota composition in female Colobus vellerosus during time periods with alpha male challenges.

The gut microbiota of group-living animals is strongly influenced by their social interactions, but it is unclear how it responds to social instability. We investigated whether social instability associated with the arrival of new males and challenges to the alpha male position could explain differences in the gut microbiota in adult female Colobus vellerosus at Boabeng-Fiema, Ghana. First, we used a data set collected during May-August 2007 and May 2008-2009 that consisted of (i) 50 fecal samples from adult females in eight social groups for V4 16S rRNA sequencing to determine gut microbiota composition, and (ii) demographic and behavioral data ad libitum to determine male immigration, challenges to the alpha male position, and infant births and deaths. Sørensen and Bray-Curtis beta diversity indices (i.e., between-sample microbiota variation) were predicted by year, alpha male stability, group identity, and age. Next, we used a more detailed behavioral data set collected during focal observations of adult females in one group with a prolonged alpha male takeover and three cases of infant loss, to create 12-month versus 3-month 1-m proximity networks that preceded and overlapped the gut microbiome sampling period in that group. The long versus short-term networks were not correlated, suggesting temporal variation in proximity networks. In this group, beta diversity among the five adult females was predicted by similarity in infant loss status and short-term (rather than yearly) 1-m proximity ties. Although the mechanism driving this association needs to be further investigated in future studies, our findings indicate that alpha male takeovers are associated with gut microbiota variation and highlight the importance of taking demographic and social network dynamics into account.

Embracing certainty in uncertain times: Macroeconomic uncertainty, third‐party assurance, and CSR performance

AbstractOur study investigates whether macro‐level uncertainty on the future economic prospects, referred to as macroeconomic uncertainty, affects corporate social responsibility (CSR) performance. Two competing theories, namely, the real options theory and the risk management theory, offer different perspectives on whether firms would increase or decrease their CSR performance in response to macroeconomic uncertainty. Existing literature documents inconclusive empirical evidence about this matter. Employing a novel and unbiased measure of macroeconomic uncertainty and drawing upon data from U.S. firms between 2006 and 2017, we find that CSR performance is negatively associated with macroeconomic uncertainty. We also document that the negative association between macro uncertainty and CSR performance is attenuated for firms that have their CSR reports independently assured by third‐party experts. The results are robust to controlling for firm characteristics, an alternative measure of macroeconomic uncertainty, and an alternative sample period excluding the 2008–2009 Financial Crisis.

A longitudinal examination of anti-corruption disclosure in the banking sector of a least-developed economy: does board composition make a difference?

PurposeThis study focuses on anti-corruption disclosure (ACD) as a critical indicator of a bank’s commitment to combat corruption. It seeks to measure the level of ACD in banking companies. Emphasizing the pivotal role of board directors in ensuring corporate accountability and transparency, the study further explores the connection between board composition and ACD.Design/methodology/approachThis study adopts automated content analysis (using keyword search) to measure the level of ACD in the annual reports of listed banks in Bangladesh. Drawing upon agency theory and resource-dependence theory, the study proposes that the collective monitoring and resources facilitated by a well-structured board (size, gender diversity and independence) significantly influence a bank’s commitment to combat corruption. The paper employs linear regression to examine the hypotheses. The reliability of the findings is further validated through the application of the Generalized Method of Moments (GMM) and Quantile Regression.FindingsThe results indicate a steady rise in ACD over the sample period (2014–2022). The analysis establishes that larger board sizes and a greater presence of female directors are positively associated with ACD. Notably, the study identifies a critical mass of at least three female directors for a significant positive relationship between gender diversity on the board and ACD. However, no significant relationship is observed between board independence and ACD.Practical implicationsThe study sheds light on the current state of ACD within the banking companies of a least-developed country. The findings carry significant implications for regulators to gauge banks' dedication to anti-corruption efforts and make informed decisions on issuing guidance for enhanced ACD. These findings can also assist regulators in assessing the implications of board composition and formulating guidelines within the corporate governance code.Originality/valueThis study contributes to the literature on ACD in the context of a least-developed economy. Notably, the study fills a research gap by exploring ACD in the banking industry. A key aspect of this study is its exploration of the determinants of ACD, explicitly emphasizing how board composition is likely to influence ACD.

A text mining analysis of European banks' and insurers' disclosures on climate‐related risks

AbstractThis paper empirically analyzes sustainability‐related disclosures of listed European banks and insurance companies by focusing on transition risks, physical risks as well as stranded assets as a possible consequence of transition and physical risks. We employ a text mining analysis and apply a comprehensive keyword catalog to 142 firms. The dataset used for the analysis comprises 852 annual and 551 sustainability reports, covering a sample period from 2017 to 2022. Our results show that disclosure on climate‐related risks considerably increases over the examined period, but that reporting on stranded assets is still in early stages. Moreover, European insurers report more on climate‐related risks relative to the number of analyzed tokens than banks. Finally, statistical evidence suggests that larger banks and insurers with above‐median market capitalization exhibit significantly more word hits on climate‐related risks as compared to smaller firms.

Get the balance right: lessons from UK higher education in managing environmental and economic performance

ABSTRACT Since 2008, there have been a growing number of social policies placed on UK higher education institutions (HEIs) to engage in reducing carbon emissions and meet self-imposed carbon reduction targets while producing graduates, publishing research papers and attracting research income. HEI managers thus face the challenging task of having to determine the optimal level between environmental performance and economic performance – from activities that generate income, to which we refer as overall efficiency. To that end, the current study measures the overall efficiency levels of UK HEIs from 2012/13 to 2018/19 using a slacks-based measure model that incorporates bad outputs. The study aims to determine the extent to which the optimal balance between environmental performance and economic performance has been achieved as evidenced by the efficiency of HEIs over the course of the sample period. The study also identifies factors associated with efficiency and provides policy recommendations. Over the study period, overall efficiency (incorporating the bad output of carbon emissions) initially fell and then rose in the last 2 years suggesting some optimism that carbon emissions management has improved since then. The second-stage analysis, which identifies factors associated with efficiency, suggests that the ratio of students to staff and HEIs in the Russell group is positively associated with the efficiency of inefficient HEIs. When both efficient and inefficient universities are considered, having an environmental management system is positively associated with efficiency, while the opposite is the case for having science, engineering and medicine disciplines and having carbon reduction targets.

Investigating the feasibility and potential of combining industry AMR monitoring systems: a comparison with WHO GLASS

Background Efforts to estimate the global burden of antimicrobial resistance (AMR) have highlighted gaps in existing surveillance systems. Data gathered from hospital networks globally by pharmaceutical industries to monitor antibiotic efficacy in different bacteria represent an additional source to track the temporal evolution of AMR. Here, we analysed available industry monitoring systems to assess to which extent combining them could help fill the gaps in our current understanding of AMR levels and trends. Methods We analysed six industry monitoring systems (ATLAS, GEARS, SIDERO-WT, KEYSTONE, DREAM, and SOAR) obtained from the Vivli platform and reviewed their respective isolates collection and analysis protocols. Using the R software, we designed a pipeline to harmonise and combine these into a single dataset. We assessed the reliability of resistance estimates from these sources by comparing the combined dataset to the publicly available subset of WHO GLASS for shared bacteria-antibiotic-country-year combinations. Results Combined, the industry monitoring systems cover 18 years (4 years for GLASS), 85 countries (71), 412 bacterial species (8), and 75 antibiotics (25). Although all industry systems followed a similar centralised testing approach, the criteria for isolate collection were unclear (patients selection, associated sampling periods…). For E.coli, K. pneumoniae and S. aureus, at least 65% of comparable resistance proportions were within 0.1 of the corresponding estimate in GLASS. We did not identify systemic bias towards resistance in industry systems compared to GLASS. Conclusions Combining industry monitoring systems can substantially strengthen our knowledge of global AMR burden across bacterial species and countries. High agreement values for available comparisons with GLASS suggest that data for other bacteria-antibiotic-country-year combinations only present in industry systems could complement GLASS, particularly for Priority Pathogens currently not covered. This valuable information on resistance levels could help clinicians and stakeholders prioritize testing and select appropriate antibiotics in settings with limited surveillance data.

Stability analysis of interval type-2 sampled-data polynomial fuzzy-model-based control system with a switching control scheme

AbstractThe stability of an interval type-2 (IT2) sampled-data (SD) polynomial fuzzy-model-based control system with a switching control scheme is studied in this paper. The uncertain nonlinear plant is depicted via an IT2 polynomial fuzzy model. To realize control, a switching IT2SD polynomial fuzzy controller is generated. This paper adopts a switching control scheme with a variable sampling period. The modeling domain consists of several sub-domains, and each sub-domain corresponds to a local IT2SD polynomial fuzzy controller. These local IT2SD polynomial fuzzy controllers form the switching IT2SD polynomial fuzzy controller. To aid in the stability analysis, this paper adopts a looped-functional-based technique. The imperfect premise matching concept is brought in to solve the mismatch dilemma caused by the SD control strategy and uncertainties. For decreasing the conservativeness, this paper takes into account the state information as well as the information of IT2 membership functions. The stability analysis is performed for each sub-domain, providing the potential for further relaxation. As polynomials exist in the stability conditions, this paper employs the sum-of-squares method for the stability investigation. The simulation outcomes confirm the efficacy of the proposed method.

Regulated public accessibility to municipalities’ financial reports and bond interest cost

PurposeIn this study, we examine regulated public accessibility to municipalities’ financial reports and bond interest cost. In particular, we examine whether there is information content in a component of a constrained filing period that is useful to municipal bond market participants. The component of a filing period that we focus on is the period of time between an audit report date and a regulated public accessibility date.Design/methodology/approachTo explore our research question, we collect a sample of observations from municipalities that: (1) are required to post annual/audit financial reports on a centralized state-level repository that includes a “transparent” date stamp on when reports are made publicly available and (2) have issued general obligation bonds. Our sample is limited to one observation per municipality. The sample period is 2006–2019. In terms of approach, we use an ordinary least square (OLS) regression model to empirically test whether the time period between municipalities’ audit report date and state-required repository filing date is associated with general obligation bond interest cost.FindingsWe find support for the idea that there is information content in a component of a constrained filing period. In particular, we hypothesize and find a positive association between the time period between an audit report date and a state filing date and general obligation bond interest cost. Seemingly, this component of time may provide something unique or not available in other components of a constrained filing period (e.g. the fiscal year-end date to the audit report date). In post hoc analyses, we also find that both components of the constrained filing period in our setting (i.e. the audit report date to state filing date and the fiscal year-end date to audit report date) need to be considered for either of the components to be significant. Moreover, although both components are necessary, the audit report date to state filing date component appears to have a slightly stronger association (in terms of statistical significance) with general obligation bond interest costs.Research limitations/implicationsTo our knowledge, Illinois is the only state that provides a date stamp on when municipalities’ financial information is made publicly available on a centralized repository. As such we focus on municipalities in Illinois. While this increases the internal validity of our research, it potentially limits generalizability across other states. Also, as a reflection of the sample constraint, the number of observations in our study is relatively small. As part of post hoc analyses, we take a closer look at our sample, model and variables used to test our hypothesis.Practical implicationsFor stakeholders, each component of a constrained filing period may provide unique information. For example, the time period between an audit report date and a regulated filing date may send a positive signal about the quality of financial management to investors. For regulators, requiring some sort of centralized public access to municipal financial reports that have transparent time constraints may help states provide stronger governance and help lower municipalities’ borrowing costs.Originality/valueWe use a novel approach (with the Illinois date stamp filing information) to examine our research question. Most prior research has often relied on an assumption that the time between fiscal year-end and the audit report date is the component of time that provides useful information to investors (e.g. Henke and Maher, 2016). In our setting, we explore and find that a component of a constrained filing time period (i.e. the date from an audit filing to a required public accessibility filing) may also provide impactful information to investors.

Adaptive neuro fuzzy technology to enhance PID performances within VCA for grid-connected wind system under nonlinear behaviors: FPGA hardware implementation

Wind Energy Conversion Systems (WECSs) exhibit nonlinear behavior due to internal and external disturbances, which can significantly impact the control performance. Firstly, this paper proposes a Vector Control Approach (VCA) based on Adaptive Neuro Fuzzy (ANF) of Proportional Integral Derivative (PID) controllers for a variable speed Permanent Magnet Synchronous Generator (PMSG)-based WECS connected to the grid to address these issues. The proposed ANF-PID controller combines the robustness of the fuzzy logic with the neural network's performance to ensure high accuracy, excellent tracking, and robustness against the WECS's nonlinear behavior. The neural network automates the placement of fuzzy logic membership functions. Secondly, this paper suggests a real-time hardware implementation of the VCA based on ANF-PID using a Field Programmable Gate Array (FPGA) to reduce the processing time and the WECS's sampling period. The effectiveness of the VCA based on ANF-PID controllers is validated by conducting a numerical simulation within the Matlab-Simulink using the Xilinx System Generator tool, alongside an experimental in-the-loop hardware implementation using FPGA board. Different scenarios are conducted to validate the robustness and stability of the proposed VCA based on ANF-PID control schemes, which is compared to Conventional Fuzzy PID (C-FPID) and PID controllers. The results exhibit that the VCA based on ANF-PID controllers outperforms VCA-C-FPID and VCA-PID controllers in terms of precision, tracking accuracy, and robustness against the WECS's nonlinear behavior and the PMSG parameter variations. The performances of the proposed controllers are tested under some criteria. In fact, the proposed ANF-PID controller provides a Mean Absolute Error (MAE), a Mean Squared Error (MSE) and a Root Mean Squared Error (RMSE) of 8.1911 × 10−04, 8.4181 × 10−05 and 0.0092, respectively. Compared to the C-FPID controller, the proposed controller offers an improvement gain of 98.96 %, 99.61 %, and 93.79 % of MAE, MSE, and RMSE, respectively. When compared to the PID controller, its improvement is even more significant, with a reduction of 99.9919 %, 99.9999 %, and 99.9288 % of MAE, MSE, and RMSE, respectively. In addition, the ANF-PID-based VCA utilizes hardware resources on the FPGA efficiently, requiring only 65.60 % slices LUT, 0.28 % LUTRAM, and 22.99 % FF. This makes it a more cost-effective option compared to the VCA-C-FPID controller for diverse control systems.

Resilience of ethical and nonethical stock during COVID-19 crisis: a case of Indonesia Stock Exchange

Purpose This study aims to empirically investigates the effect of the COVID-19 pandemic on ethical and nonethical stocks in Indonesia. Ethical stocks which are characterized by moral-based companies’ activities and lower debt are expected to have better resilience during the COVID-19 crisis compared to nonethical stock. Design/methodology/approach This study observes 589 firms of ethical and nonethical stock during sample periods ranging from March 2, 2020 (first case announced) to June 30, 2021. Panel regression, with some control variables, was applied. Findings Testing firms in Indonesia revealed a significant difference in stock resilience, in which ethical stock has a better resilience compared to nonethical, with Islamic socially responsible investment (SRI) stock having the highest resilience, followed by Islamic stock and then SRI stock. This study documents a significant effect of some financial criteria on the stock resilience, namely, return market (RM), market capitalization (MCAP) and share turnover (TURN). Overall, after splitting the sample into different time horizons, this study consistently reveals that ethical firms have better resilience compared to nonethical stocks. Research limitations/implications This study makes several contributions to the literature on Islamic finance, especially concerning Islamic screening with SRI factors. In practical terms, this study supports the argument that focusing on integrating environmental, social and governance criteria in sharia screening will improve the quality of Islamic firms. The “Islamic” label is not only a marketing label but also a quality certification. Originality/value This study can be used as a reference for developing Islamic finance more focused on sustainability issues including socioeconomic and human development by improving the quality of screening of Islamic firms. Therefore, this study suggests that the establishment of Islamic SRI index is very crucial and significant to promote ethical-based investment.

Critical speed models of high-resolution speed-duration profiles describe peak running demands in soccer

The purpose of this study was to characterize critical speed (CS) models for summarizing high-resolution speed-duration profiles from GPS tracking data obtained from soccer players. GPS data from 15 male NCAA Division I soccer players were collected during practices and games over a 6-week period. Moving averages of the speed data were computed for each file for duration windows spanning 0.1 to 600 seconds at 0.1-second resolution. Speed-duration profiles for each session and for the entire sampling period (“global”) were generated for each player by selecting the maximal mean speeds for each duration. Four models were fit to the profiles: the two-parameter CS (CS2) model, the three-parameter CS (CS3) model, the omni-domain speed-duration (OmSD) model, and the five-parameter logistic (5PL) model. The 5PL, CS3, and OmSD models exhibited similar goodness of fits, and all outperformed the CS2 model. Similar CS estimates were obtained for each model, whereas maximum speed ( Smax) estimates were lower for OmSD compared to the 5PL. Players exhibited a range of parameter values for CS, D′, and Smax. Smax and CS estimated from session-specific speed-duration profiles were on average higher for games compared to practices. We conclude that CS models are useful for empirically describing speed-duration profiles and for assessing peak running demands for soccer practices and games. The proposed approach could help coaches design practice activities to better mimic game demands.

Systematic review and meta-analysis of birth weight and perfluorohexane sulfonate exposures: examination of sample timing and study confidence

We examined the association between mean birth weight (BW) differences and perfluorohexane sulfonate (PFHxS) exposure biomarkers.We fit a random effects model to estimate the overall pooled effect and for different...

Characteristics, Sources Apportionment, and Health Risks of PM2.5-bound PAHs and Their Derivatives Before and After Heating in Zibo City

Atmospheric polycyclic aromatic hydrocarbons (PAHs) and their derivatives are a global problem that influences the environment and threatens human health. To investigate the characteristics, sources, and health risk assessment of PM2.5-bound PAHs and their derivatives, PM2.5 were collected at an urban site in Zibo from November 5 to December 26, 2020, and the concentrations of 16 conventional PAHs, nine NPAHs, and five OPAHs in PM2.5 were analyzed using gas chromatography-mass spectrometry. Source apportionment of PAHs and their derivatives was conducted using diagnostic ratios and a PMF model, and the health risks of PAHs and their derivatives to adult men and women were evaluated using the source-dependent incremental lifetime cancer risk (ILCR) model. The results showed that the average concentrations of ∑16pPAHs, ∑9NPAHs, and ∑5OPAHs in PM2.5 of Zibo City during the sampling period were (41.61 ± 13.40), (6.38 ± 5.70), and (53.20 ± 53.47) ng·m-3, respectively. The concentrations of the three PAHs increased significantly after heating, which were 1.31, 2.04, and 5.24 times larger than those before heating. During the sampling period, Chr, BaP, and BaA were the dominant components of pPAHs; 9N-Ant and 2N-Flt + 3N-Flt were the dominant components of NPAHs; and ATQ and BZO were the dominant components of OPAHs. Source apportionment results showed that motor vehicles were the main source of PAHs and their derivatives in PM2.5 before heating, whereas after heating, the main sources were the mixed source of coal and biomass combustion and secondary formation. The total BaP equivalent (TEQ) was 14.5 ng·m-3 during the sampling period, and the TEQ increased significantly after heating, which was approximately 1.2 times of that before heating. Assisted by the individual PAH source apportionment results, the ILCR of PM2.5-boundPAHs and NPAHs in Zibo City had a certain potential carcinogenic risk for adult males (1.06 × 10-5) and females (9.32 × 10-6). Among them, the health risks of PAHs from gasoline vehicles, diesel vehicles, and coal/biomass combustion were significantly higher than those from other emission sources.

Analyzing Nexus between Crude Oil, Gold, Dollar and Equity Markets with Structural Break: ARDL Evidence from India

This paper explores the price relations between the Crude oil, Gold, US dollar, and equities during several economic episodes. The long- and short-term causal relationships between asset markets are examined in this study. The research uses a ‘Vector Error Correction Model (VECM)’ and an ‘Autoregressive Distributed Lag (ARDL)’ bounds test to examine monthly data from April 1999 to March 2022. The results demonstrate the weak connections between asset markets throughout the different sample periods. Furthermore, the integration of most markets is uneven and changes over time. The currency and equity markets are adjusting to the long-run equilibrium only at a slow pace. We suggest that systematic risk factors must be taken into account while jointly modeling market linkages. This study improves on previous research in the subject by demonstrating the time-varying effects of asset price links on portfolio optimizations in different economic episodes.