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One gorgeous natural event which attracts tourists to a destination is an eclipse. This paper is an initial attempt to investigate the effective factors for early planning in destinations for a total solar eclipse. A qualitative-quantitative methods (with exploratory factor analysis) were used. The results reveal seventeen effective factors and five variables such as management and planning at different levels; setting up a news agency website and social networks to increase the level of public awareness and advertising; local involvement; organizing local festivals in nearby villages and cities; and public involvement as the main factors in early planning in destinations for a total solar eclipse. The results also illustrate that there is correlation between the identified variables. Eclipse events in a short period of time attract numerous tourists to a destination, and this is a form of mass tourism. Therefore, early management of the event plays an axial role in the sustainable development of the region.

The cryptocurrency market offers attractive but risky investment opportunities, characterized by rapid growth, extreme volatility, and uncertainty. Traditional risk management models, which rely on probabilistic assumptions and historical data, often fail to capture the market's unique dynamics and unpredictability. In response to these challenges, this paper introduces a novel portfolio optimization model tailored for the cryptocurrency market, leveraging a credibilistic CVaR framework. CVaR was chosen as the primary risk measure because it is a downside risk measure that focuses on extreme losses, making it particularly effective in managing the heightened risk of significant downturns in volatile markets like cryptocurrencies. The model employs credibility theory and trapezoidal fuzzy variables to more accurately capture the high levels of uncertainty and volatility that characterize digital assets. Unlike traditional probabilistic approaches, this model provides a more adaptive and precise risk management strategy. The proposed approach also incorporates practical constraints, including cardinality and floor and ceiling constraints, ensuring that the portfolio remains diversified, balanced, and aligned with real-world considerations such as transaction costs and regulatory requirements. Empirical analysis demonstrates the model's effectiveness in constructing well-diversified portfolios that balance risk and return, offering significant advantages for investors in the rapidly evolving cryptocurrency market. This research contributes to the field of investment management by advancing the application of sophisticated portfolio optimization techniques to digital assets, providing a robust framework for managing risk in an increasingly complex financial landscape. [ABSTRACT FROM AUTHOR]

In this study, we apply a novel approach of portfolio diversification—the robust maximum diversified (RMD)—to a small and developing economy's stock market. Using monthly returns data from August 2019 to May 2024 of 18/19 stocks listed on Fiji's South Pacific Stock Exchange (SPX), we construct the RMD portfolio and simulate with additional constraints. To implement the RMD portfolio, we replace the covariance matrix with a matrix comprising unexplained variations. The RMD procedure diversifies weights, and not risks, hence we need to run a pairwise regression between two assets (stocks) and extract the R-square to create a P-matrix. We compute each asset's beta using the market-weighted price index, and the CAPM to calculate market-adjusted returns. Next, together with other benchmark portfolios (1/N, minimum variance, market portfolio, semi-variance, maximum skewness, and the most diversified portfolio), we examine the expected returns against the risk-free (RF) rate. From the simulations, in terms of expected return, we note that eight portfolios perform up to the RF rate. Specifically, for returns between 4 and 5%, we find that max. RMD with positive Sharpe and Sortino (as constraints) and the most diversified portfolio offer comparable returns, although the latter has slightly lower standard deviation and downside volatility and contains 94% of all the stocks. Portfolios with returns between 5% and the RF rate are the minimum-variance, the semi-variance, and the max. RMD with positive Sharpe; the latter coincides with the RF rate and contains the most (94%) stocks compared to the other two. An investor with a diversification objective, some risk tolerance and return preference up to the RF rate can consider the max. RMD with positive Sharpe. However, depending on the level of risk-averseness, the minimum-variance or the semi-variance portfolio can be considered, with the latter having lower downside volatility. Two portfolios offer returns above the RF rate—the market portfolio (max. Sharpe) and the maximum Sortino. Although the latter has the highest return, this portfolio is the least diversified and has the largest standard deviation and downside volatility. To achieve diversification and returns above the RF rate, the market portfolio should be considered. [ABSTRACT FROM AUTHOR]

Assessments in education enables educators, curriculum designers, and program developers to evaluate the success of their programs. It also allows for assessing learners enrolled in the programs. Assessment frameworks emanate from a Western and positivistic stance and tend to disregard linguistic and cultural diversity from the mainstream European point of view. That said, failing to recognize the distinctions of diverse learners has led to inequitable learning experiences for minority learners, who have distinct ways of knowing, worldviews, and epistemologies, and have led to their high-rates of drop-out and under-performance in academe. Thus, this study reviews the literature on assessment and has found that current assessment frameworks have contributed to the high drop-out rate and academic under-performance among minority learners. This, however, could be resolved when educators indigenize and re-define assessment frameworks and assess their minority learners' academic performance using culturally appropriate frameworks that incorporate their Indigeneity and ways of knowing. [ABSTRACT FROM AUTHOR]

Objective(s): Peripheral nerve injury (PNI) is a critical clinical issue primarily caused by trauma. Tissue engineering approaches using nanofiber scaffolds have been extensively explored to improve material quality and create an environment resembling the natural extracellular matrix (ECM). Materials and Methods: In this study, we employed electrospinning technique to fabricate a composite scaffold comprising poly(ɛ-caprolactone) (PCL) and collagen (Col) loaded with all-trans retinoic acid (RA), a neural patterning and signaling chemical known to promote nerve regeneration. Results: The synthesized nanofiber scaffold exhibited a diameter of 391±79 nm and a tensile strength of 250±13 MPa, providing sufficient support for native peripheral nerve regeneration. The inclusion of Col enhanced the scaffold's hydrophilic behavior (contact angle: 43±6°), ensuring stability in an aqueous solution. Moreover, the results demonstrated the proliferation and adhesion of nerve cells on the scaffold, aligning with the directions of the warp and weft of the nanofiber mat. Importantly, the scaffolds demonstrated non-toxicity, making them a promising substitute for the native ECM for enhanced cell attachment and proliferation. Finally, immune-histochemistry analyses further confirmed that the scaffolds supported the release and growth of neurites, promoting cell differentiation toward nerve repair. Conclusion: The RA-loaded scaffolds demonstrated the enhanced biocompatibility, supported neurite growth, and showed potential as a capable candidate for nerve regeneration. [ABSTRACT FROM AUTHOR]

The 1/N investment strategy, characterized by equally allocating wealth among available investment options, has garnered significant scholarly attention. Simultaneously, risk assessment and management play a critical role in financial decision-making, leading to the development of a diverse array of risk measure models. This paper aims to synthesize these two strategies and propose a novel approach for constructing a naive diversification strategy by incorporating commonly employed risk measures in financial analysis. The research involves an in-depth exploration of various risk measures utilized by financial professionals to enhance effective risk management. These measures include Mean-Variance (MV), Mean Absolute Deviation (MAD), Semi Standard Deviation (MSV), Value at Risk (VaR), Conditional Value at Risk (CVaR), Entropic Value at Risk (EVaR), Drawdown at Risk (DaR) of uncompounded cumulative returns, Conditional Drawdown at Risk (CDaR) of uncompounded cumulative returns, and Entropic Drawdown at Risk (EDaR) of uncompounded cumulative returns. To validate the efficacy of the proposed model, a real-world empirical case study utilizing the annual financial statements of the NASDAQ100 (NDX) database is conducted. The empirical findings from this study carry practical implications for investors and risk managers engaged in portfolio management. [ABSTRACT FROM AUTHOR]

Introduction: Recently, membrane microfluidic chips (MFCs) have become available to study biological basement membranes. The nanofiber (NF) membranes are suitable substrates for cell attachment and trapping, as demonstrated by their surface properties. In this study, a novel microfluidic device based on the electrospun collagen-modified polyethylene terephthalate (PET)/polydimethylsiloxane (PDMS) was designed and fabricated to mimic biological basement membranes. Methods: Hybrid NF containing PDMS/PET and collagen were successfully fabricated by two-nozzle electrospinning, and then PDMS chips were fabricated by soft lithography. The integrity of the membrane and NFs structure before (BC) and after cross-linking (AC) was evaluated by SEM, AFM, contact angle, FT-IR, BET, and tensile analysis. For further studies, numerical simulations were performed to evaluate the microfluidic flow in the PDMS-based device and demonstrate the fluid flow on top of a membrane. In the simulation, we used COMSOL Multiphysics to study the influence of flow rate and different surface topographies on the velocity and shear rate characteristics. Results: Cross-linking of NFs increased the diameter of NF (from 391 ± 169 nm to 660 ± 199 nm), hydrophilicity, elongation, and surface roughness (from 66.9 nm to 296.7 nm), but decreased the pore size volume of NFs (0.06 cm³ g-1 to 0.01 cm³ g-1). Bonding of NFs was possible through the use of oxygen plasma activated materials based on PDMS and PET. After bonding the NFs in the channels with oxygenated plasma, human umbilical vein endothelial cells (HUVEC) and glial cell line (C6) were successfully cultured and stained in MFC with dynamic conditions for 24 h at a flow rate of 10 µl/min. Discussion: The rougher microchannels exhibited a non-uniform shear rate distribution, and the flow rate was a parameter with a significant influence on the shear rate and velocity (roughness=0.3 µm). These results provided reliable evidence that the combination of electrospun NFs and cell culture can closely resemble a cell matrix. [ABSTRACT FROM AUTHOR]

In the wake of recent turbulent events in the global economy, the need for robust methods to navigate uncertainties in financial markets has become increasingly apparent. Robust portfolio optimization (RPO) offers a solution by devising investment strategies that perform well even under adverse scenarios of uncertain inputs such as returns and covariances. This paper conducts a systematic review of recent developments and extensions in the field of RPO. Leveraging bibliometric analysis and visual mapping techniques, we scrutinize 1085 articles published between 2000 and 2023. Our analysis traces the evolution and trends within RPO, examining the interconnectedness among articles, authors, sources, countries, and keywords. The insights gleaned from our study can guide future research endeavors in this domain and aid practitioners in making more informed investment decisions. [ABSTRACT FROM AUTHOR]

One gorgeous natural event which attracts tourists to a destination is an eclipse. This paper is an initial attempt to investigate the effective factors for early planning in destinations for a total solar eclipse. A qualitative-quantitative methods (with exploratory factor analysis) were used. The results reveal seventeen effective factors and five variables such as management and planning at different levels; setting up a news agency website and social networks to increase the level of public awareness and advertising; local involvement; organizing local festivals in nearby villages and cities; and public involvement as the main factors in early planning in destinations for a total solar eclipse. The results also illustrate that there is correlation between the identified variables. Eclipse events in a short period of time attract numerous tourists to a destination, and this is a form of mass tourism. Therefore, early management of the event plays an axial role in the sustainable development of the region. [ABSTRACT FROM AUTHOR]