Search Results (156)

Sectoral vulnerability to distinct crisis types in small, open, and geopolitically exposed markets—such as Jordan—remains insufficiently quantified, constraining targeted policy design and portfolio allocation. This study’s primary purpose is to establish a transparent, comparable metric of sector-level market resilience that reveals how crisis typology reorders vulnerabilities and shapes recovery speed. Applying this framework, we assess Jordan’s equity market across three archetypal episodes—the Global Financial Crisis, the Arab Spring, and COVID-19—to clarify how shock channels reconfigure sectoral risk. Using daily Amman Stock Exchange sector indices (2001–2025), we estimate $GARCH\left(\mathrm{1,1}\right)$ models for each sector–crisis window and summarize volatility dynamics by persistence $(\alpha +\beta )$, interpreted as an inverse proxy for resilience; complementary diagnostics include maximum drawdown and days-to-recovery, with nonparametric (Kruskal–Wallis) and rank-based (Spearman, Friedman) tests to evaluate within-crisis differences and cross-crisis reordering. Results show pronounced heterogeneity in every crisis and shifting sectoral rankings: financials—especially banking—display the highest persistence during the GFC; tourism and transportation dominate during COVID-19; and tourism/electric-related industries are most persistent around the Arab Spring. Meanwhile, food & beverages, pharmaceuticals/medical, and education recurrently exhibit lower persistence. Higher persistence aligns with slower post-shock normalization. We conclude that resilience is sector-specific and contingent on crisis characteristics, implying targeted policy and portfolio responses; regulators should prioritize liquidity backstops, timely disclosure, and contingency planning for fragile sectors, while investors can mitigate crisis risk via dynamic sector allocation and volatility-aware risk management in emerging markets. Full article

A novel thermal conductivity prediction model was developed to address the complex influence of pore structure in porous materials. This model incorporates pore size (d) and a pore distribution parameter (t) to calculate the material’s thermal conductivity. To validate the model’s accuracy, geopolymer foamed concrete (GFC) samples with varying pore structures were fabricated. These utilized ground granulated blast furnace slag (GGBS) as the precursor, a mixed solution of sodium hydroxide (NaOH) and sodium silicate as the alkaline activator, and sodium stearate (NaSt), hydroxypropyl methylcellulose (HPMC), and sodium carboxymethyl cellulose (CMC-Na) as foam stabilizers. Conventional pore size characterization techniques exhibit limitations; consequently, this research implements a high-fidelity machine vision-driven image analysis methodology. Pore size measurement is achieved through a combined technical approach involving equivalent diameter modeling and morphological optimization. The feasibility of the proposed theory is validated by our experimental data and data from previous literature, with the error between experimental and theoretical values maintained within 5%. The value of t increases with increasing porosity and increasing disorder in pore distribution. Based on the experimental data obtained in this study and the research data from previous scholars’ studies, the t value for porous materials can be categorized according to porosity: when porosity is approximately 30%, t ≈ 0.9; when porosity is 55~65%, t ranges from 1.2 to 1.3; and when porosity is approximately 80%, t ranges from 1.9 to 2.2. Full article

This study examined the factor structure of Green, Grey, and Red EU securities using extended asset pricing models built on the Fama–French and Carhart frameworks. The findings show improved return predictability and consistently negative risk-adjusted alpha across categories post-Global Financial Crisis (GFC), suggesting systematic overestimation of expected returns. All environmental asset types are positively linked to the MKTRF, SMB, HML, and HML^Devil factors, indicating exposure to core risk premia. Green securities exhibit elevated currency risk and persistent negative momentum, while Red assets transition from positive to negative momentum. Green and Red securities show stronger gold associations post-GFC, signaling a hedging role. Grey assets shift away from safe-haven behavior, becoming more sensitive to volatility. FEAR factor exposure and QML results suggest evolving sensitivity and declining quality, particularly in Grey assets. These findings underscore the need for enriched asset pricing models to capture dynamic risk characteristics in environmental assets within the EU financial markets. Full article

This paper uses a statistical test based on entropy theory to propose a new way to distinguish between interdependence, contagion, and the decoupling hypotheses in the context of shock transmission and spillover. Applying the proposed approach, the three hypotheses are examined when measuring the extent of shock spillover between selected developed and emerging markets during idiosyncratic crisis and normal periods. The US and EU are identified as developed economies. However, emerging markets are classified by regions to determine whether their responses to shocks from developed economies are homogeneous or heterogeneous depending on the region to which they belong. The suggested entropy test is based on the conditional correlations obtained from an asymmetric dynamic conditional correlation generalized autoregressive conditional heteroscedasticity (A-DCC GARCH) model. In addition to economic methods, statistical methods based on the regime-switching technique are used to date the different phases of the global financial crisis (GFC) and the European sovereign debt crisis (ESDC). Our findings show that all emerging markets decoupled from developed economies in at least one of the phases of the two crises. These findings provide valuable insights for policymakers, investors, and asset managers for portfolio allocation and financial regulations. Full article

Samphire (Crithmum matrimum), a halophyte, thrives in saline environments due to its salt tolerance, which is partly attributed to miR167. However, the functional role of miR167 in human cells is unclear. This study explores the role of extracellular vesicles (EVs) derived from C. matrimum callus in skin regeneration, highlighting the potential of miRNA tae-miR167c-5p (miR167). Calluses were successfully induced and scaled for EV isolation. Characterization confirmed the presence of plant EV biomarkers and EVs with an average size of 136.6 nm. Cm-callus EVs enhanced wound healing and skin regeneration in human fibroblasts (HFF cells and CCD-986Sk cells) by modulating key genes, in particular, by downregulating MMP1 and upregulating COL1A1 and VEGFA. Small RNA sequencing revealed an enrichment of miR167 in Cm-callus EVs. Transfection with an miR167 mimic replicated these regenerative effects. Computational predictions identified PPP3R2, which is linked to the MAPK and NFAT pathways, as a potential target of miR167. This study demonstrates the efficacy of Cm-callus EVs and miR167 in promoting skin regeneration without cytotoxicity, providing insights into their therapeutic potential and calling for further experimental validation of target interactions. Full article

Wound healing is a complex and dynamic process involving several stages of tissue repair. This study has shown that extracellular vesicles (EVs) derived from the callus of Camellia japonica L. and their associated microRNAs (miRNAs) possess significant wound healing activities. In human fibroblasts, EVs from C. japonica L. stimulated wound healing and upregulated collagen gene expression. The EVs also decreased inflammation levels in human keratinocytes, supporting wound healing. Among the miRNAs identified, miR408, one of the abundant miRNAs in the EVs, also showed similar wound healing efficacy. These findings suggest that both EVs and miR408 from the callus of C. japonica L. play a pivotal role in promoting wound healing. Additionally, this study shows that the regulation of miRNAs between different kingdoms can be achieved and suggests a new direction for the utilization of plant-derived components. Full article

This study examines the relationship between crude oil returns (CRT) and Islamic stock returns (ISR) in BRIC countries during the Global Financial Crisis (GFC), employing wavelet-based comovement analysis and regression models that incorporate both contemporaneous and lagged CRT across 40 cases. The wavelet analysis reveals strong long-term comovement at low frequencies between ISR and CRT during the GFC. Contemporaneous regressions show that increases (decreases) in CRT align with corresponding movements in ISR. Lagged regressions indicate that CRT can predict ISR up to one week ahead for Brazil, Russia, and China, and up to two weeks for India, although the predictive strength weakens beyond this window. These findings challenge the perception that Islamic stocks were immune to the GFC, showing they were affected by global oil market dynamics, albeit with varying degrees of resilience across countries and time horizons. Full article

Nanomaterials have been one of the latest trends used by geotechnical engineers for improving insufficient soil criteria. This study aims to assess the usability of CaCO₃, nano-CaCO₃ and Glass Fiber Chopped Strands (GFCSs) in the improvement procedures for clay soil media by performing traditional and laboratory model experiments. Clay samples mixed with CaCO₃ at 5%, nano-CaCO₃ at 0.75% and GFCSs at 2.0% separately provided 1.49, 1.68 and 1.86 times increments in the bearing capacity values in comparison with plain clay, respectively. Mixtures of clay, GFCSs at 1.5% and nano-CaCO₃ at 0.75% enabled the most optimal result of 2.58 times improved bearing capacities. Curing durations had a significant effect on increasing the bonding between nano-CaCO₃ and clay which led to further improved conditions. Settlement enhancements of up to 6.80% were recorded for the mixtures of nano-CaCO₃, GFCSs and clay as well. Thus, improvements were reached in terms of bearing capacity and settlements along with the applicability and economy of the related procedures, of which the details can be seen in the following sections of this study. Full article

This research investigates a novel hybrid E-glass fiber coated with a thin amorphous carbon (coke) layer, referred to as GF@C, designed to enhance the affinity of fiber with a polymer matrix. Acrylonitrile butadiene styrene (ABS), an engineering thermoplastic, was selected as the matrix to form the composite. The carbon coating was produced by pyrolyzing a lubricant oil (Lo) layer applied to the glass fiber strands. To promote the formation of graphite crystallites during carbonization, a small amount (x wt.% of Lo) of coronene (Cor) was added to Lo as a dopant. The resulting doped fibers, denoted GF@C_Lo-Cor(x%), were embedded in ABS at 70 wt.%, leading to significant improvements in mechanical properties. At the optimal doping level (x = 5), the composite achieved a Young’s modulus of 1.02 GPa and a tensile strength of 6.96 MPa, substantially higher than the 0.4 GPa and 3.81 MPa observed for the composite with the pristine GF. This enhancement is attributed to a distribution of graphite crystallites and their graphitization extent in the carbon coating, which improves interfacial bonding and increases chain entanglement. Additionally, GF@C_Lo-Cor(x%)–ABS composites (x = 0 and 5) exhibit significantly higher dielectric constant–temperature profiles than GF–ABS, attributed to the formation of diverse chain adsorption states on the C-coating. Full article

This study examines the behavioral mechanism of sustainable consumption through which greenwashing (GW) perception influences consumers’ intention to purchase green food, with a particular focus on Chinese consumers. Grounded in the value-based adoption model (VAM), we propose a structural model that incorporates perceived benefit (PB) and perceived sacrifice (PS) as mediating variables and GW perception as a moderating variable. Using survey data from 347 Chinese respondents, the analysis is conducted via partial least squares structural equation modeling. The results indicate that environmental knowledge, environmental awareness (EA), green food characteristics (GFCs), and consumer characteristics significantly enhance PB, whereas EA and GFCs reduce PS. PB has a positive effect on green food purchase intention, whereas PS has a negative effect. Notably, GW perception does not significantly moderate the relationship between PB and purchase intention, but it does intensify the negative impact of PS on purchase intention. This suggests that consumers who are sensitive to GW are more likely to reject green food products when they experience a high PS. This study contributes to the literature by extending the application of the VAM in the context of sustainable consumption and offering empirical insights into the psychological effects of GW. Practical implications include marketing strategies aimed at reducing PS and fostering trust through transparent, verifiable green claims. Policymakers are encouraged to improve certification systems and public education efforts to alleviate consumer skepticism in the green food market. Full article

Rising global temperatures increase skin exposure to heat stress, which can impair skin structure and function. While several cosmetic ingredients have been developed to mitigate heat-induced damage, most primarily aim to enhance hydration or suppress inflammation, lacking mechanistic insights into their action under heat stress. This study assessed E. artemiae-derived SUPER-T and its exosome form, Thermasome, in heat-stressed human skin fibroblasts. Transcriptomic profiling revealed that heat stress upregulated heat-related thermal receptors and downregulated key extracellular matrix (ECM)-related genes. Notably, treatment with SUPER-T upregulated expression of these genes, suggesting a reparative role as a barrier to alleviate heat stress at the dermal–epidermal junction. For its application in a field of cosmetics, SUPER-T encapsulated in exosomes (Thermasome) enhanced the heat resilience, suggesting its better transdermal and heat protective effects. Thermasome further improved skin heat resilience and enhanced ECM gene expression including collagen genes. Our findings provide a mechanistic basis for the development of functional cosmetical materials that target ECM remodeling under heat-stressed conditions. Full article

The electrical grid is undergoing increasing integration of decentralized power sources connected to the low-voltage network. In this context, the concept of a microgrid has emerged as a system comprising small-scale energy sources, loads, and storage devices, coordinated to operate as a single controllable entity capable of functioning in either grid-connected or islanded mode. The microgrid may be organized in a centralized configuration, such as a master-slave scheme, wherein the centralized converter, i.e., the grid-forming converter (GFC), plays a pivotal role in ensuring system stability and control. This paper introduces a plug-in repetitive controller (RC) strategy tuned to even harmonic orders for application in a three-phase GFC, diverging from the conventional approach that focuses on odd harmonics. The proposed control is designed within a synchronous reference frame and is targeted at centralized AC microgrids, particularly during islanded operation. Simulation results are presented to assess the microgrid’s power flow and power quality, thereby evaluating the performance of the GFC. Additionally, the proposed control was implemented on a Texas Instruments TMS320F28335 digital signal processor and validated through hardware-in-the-loop (HIL) simulation using the Typhoon HIL 600 platform, considering multiple scenarios with both linear and nonlinear loads. The main results highlight that the RC improves voltage regulation, mitigates harmonic distortion, and increases power delivery capability, thus validating its effectiveness for GFC operation. Full article

The implications of digital finance for financial stability has come under serious scrutiny since the aftermath of the 2008 global financial crisis (GFC). Empirical evidence on this nexus are somewhat inconsistent and ambiguous. This study therefore attributes this puzzle to multiple structural breaks (MSBs) which were long neglected by previous studies. Consequently, this study aims to identify possible MSBs in the digital finance–stability nexus and examine if its impact is consistent/weakened in the presence of MSBs in a sample of 41 developing African economies for the 2004–2023 periods. Results from the PCA index generation report that instability is more susceptible to bank crisis/Z-score. Again, the panel extension of BP98 MSBs detection identified three breaks with their confidence intervals overlapping the periods of the 2006–2011 GFC/subprime mortgage crises, the 2012–2016 Br-exit referendum and the 2017–2021 COVID 19 pandemic/Ukraine war. The quantile regression methodology also shows that these breaks weaken the impact of digital finance (i.e., mobile banking and internet banking) on financial stability, particularly for economies at lower quantiles of financial stability but with marginal effects for economies at higher quantiles. The study concludes that digital finance can stabilize the financial system of developing economies when shocks from structural breaks are controlled. Therefore, the study contributes to knowledge by developing a new econometric model for BP98 panel extension of MSBs detection, calibrating an index for financial stability and detecting valid break dates for three major breaks. Structural and financial development through policy coordination to forestall the effects of structural breaks were recommended. Full article

This study conducts a macro-level comparative analysis of the eco-efficiency in the agricultural sectors of the European Union (EU) member states and Türkiye from 2003 to 2022. By treating countries as decision-making units, this research offers a holistic overview of how national-level inputs and outputs shape the aggregate performance, focusing on the trade-offs between economic value generation and environmental pressures. An input-oriented Data Envelopment Analysis (DEA) model, based on Variable Returns to Scale (VRS), was employed. The model employs three inputs—compensation of employees (COE), energy consumption (EC), and gross fixed capital formation (GFC)—and two outputs—agricultural gross domestic product (GDP) and GHG emissions (GGEs). All variables were normalized by agricultural land area per country to account for scale differences. The findings reveal significant disparities in the eco-efficiency across countries and over time. Notably, Türkiye consistently demonstrated a high performance, frequently serving as a benchmark. In contrast, several Eastern European countries exhibited lower scores, suggesting significant room for structural improvement at the national level. The results point to the considerable potential for reducing energy and labor inputs in many countries. Instead of offering specific policy prescriptions, this study provides a diagnostic tool that identifies national-level performance gaps, informs policy discussions on resource allocation, and highlights priority areas for more detailed investigation. Full article

This study examines the explainability, validity, and applicability of multi-factor models in explaining the returns of Green (eco-friendly), Grey (neutral), and Red (environmentally harmful) EU securities. We apply the Fama–French three-factor and five-factor models, along with the Carhart four-factor model, to analyze changes in risk exposures and adjusted abnormal returns (alphas) before and after the 2009 global financial crisis (GFC). Green and Grey securities exhibit positive SMB loadings, while Grey’s HML shifts from negative to positive over time. Both Green and Red securities show positive SMB and HML factors but negative alphas in the second period, indicating systematic underperformance. Additionally, for Red assets, momentum (MOM), profitability (RMW), and investment (CMA) factors are positive and significant in the first period but become insignificant or negative later. These findings highlight structural shifts in factor exposures and contribute to the ongoing debate on the most suitable classical asset pricing framework for environmentally classified assets, offering insights into the effectiveness of traditional factor models in different classes of environmental assets in finance. Lastly, the three-factor model better captures the common variation in Green and Grey asset returns. Specifically, the 4-factor model and the HML Devil factor prove to be more effective in explaining returns for Red securities. Full article