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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]

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]

Gold nanoparticles possess attractive properties that make them valuable in medicine. Recently, green synthesis of nanoparticles has been a target of research due to its simplicity, safety, eco-friendliness and cost-effectiveness. This study describes the green synthesis of gold nanoparticles via aqueous extract of Melissa officinalis L. (Mel). The various parameters affecting the synthesis of gold nanoparticles (pH, gold salt concentration, extract volume, temperature, and reaction time) were investigated and optimized. Ultraviolet–Visible spectrophotometry, Dynamic light scattering, Transmission electron microscopy, and Fourier-transform infrared spectroscopy were applied to characterize synthesized gold nanoparticles (GNP-Mel). The antioxidant activity of Mel extract and GNP-Mel was performed by 2,2-diphenyl-1-picrylhydrazyl free radical scavenging test. The effect of GNP-Mel on cell viability of H9C2 rat cardiomyocytes was evaluated using Alamar blue assay. The results indicated uniform sphericalshaped gold nanoparticles with an average particle size of 8 nm and a zeta potential value of -31.7 mV, which demonstrates the high stability of GNP-Mel. The Mel extract and GNP-Mel showed the highest antioxidant activity with percentages of 77.69 ± 1.18% and 59.64 ± 1.29% at a maximum concentration (of 100 μg/ml), respectively, which can be compared with Vitamin C (89.34 ± 1.34%). Moreover, the result of Alamar blue assay represented a higher than 80% cell viability in the presence of 20, and 50 μg/ml of GNP-Mel and likewise, a higher than 50% cell viability in the presence of 100 and 170 μg/ml of GNP-Mel. Overall, the findings show that the green synthesized gold nanoparticles are appropriate candidates for biomedical applications. [ABSTRACT FROM AUTHOR]

The risk of clot formation in blood-contacting devices is a significant concern. Therefore, development of biomaterials with improved hemocompatibility is a clinical need. Altering surface properties is an effective strategy to enhance the hemocompatibility. We have investigated the effect of hydrophilic polyethylene glycol (PEG) amount over the hydrophobic polycarbonate (PC) on hemocompatibility of polyurethanes. The presence of PEG on the surface was evaluated using ATR, AFM, and WCA. At above 20% of PEG to PC ratios, exhibit zero WCA, considerable improvement in hemocompatibility, was achieved. The results indicated the synthesized PUs could be used as coatings of cardiovascular devices. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of metal complexes have garnered significant attention due to their versatile applications in scientific and biomedical fields. In this research, two novel copper (Cu) complexes, [Cu(L)(L′)(H2O)2] (1) and [Cu(L)(Im)H2O] (2), where L = pyridine-2,6-dicarboxylic acid, L′ = 2,4-diamino-6-hydroxypyrimidine, and Im = imidazole, were investigated concerning their sonochemical synthesis, spectroscopic analysis, and biological activity. The complexes' structural characterization was achieved using analytical techniques, including single-crystal X-ray structure determination, FTIR, PXRD, TGA and DTA, SEM, TEM, and EDS. Complex (1) displayed a six-coordinated Cu2+ ion, while complex (2) exhibited a five-coordinated Cu2+ ion. The crystal structures revealed monoclinic (C2/c) and triclinic (P-1) space groups, respectively. Both complexes showcased zero-dimensional (0D) supramolecular networks, primarily driven by hydrogen bonding and π–π stacking interactions, which played pivotal roles in stabilizing the structures and shaping the unique supramolecular architecture. Both complexes demonstrated significant antioxidant activity, suggesting their capability to neutralize free radicals and mitigate oxidative stress-related diseases. Hemolysis percentages were less than 2%, per the ASTM F756-00 standard, indicating non-hemolytic behavior. Low cytotoxicity was observed against fibroblast and MCF-7 cell lines. They do not exhibit antibacterial activity against Escherichia coli and Staphylococcus aureus. These findings suggest that the synthesized Cu2+‒complexes hold considerable promise for applications in drug delivery and cancer treatment. This research contributes to the advancement of supramolecular chemistry and the development of multifunctional materials for diverse scientific and medical applications. [ABSTRACT FROM AUTHOR]

Most Artificial Intelligence (AI) implementations so far are based on the exploration of how the human brain is designed. Nevertheless, while significant progress is shown on specialized tasks, creating an Artificial General Intelligence (AGI) remains elusive. This manuscript proposes that instead of asking how the brain is constructed, the main question should be how it was evolved. Since neurons can be understood as intelligent agents, intelligence can be thought of as a construct of multiple agents working and evolving together as a society, within a long-term memory and evolution context. More concretely, we suggest placing Multiple Neighborhood Cellular Automata (MNCA) on a blockchain with an interaction protocol and incentives to create an AGI. Given that such a model could become a "strong" AI, we present the conjecture that this infrastructure is possible to simulate the properties of cognition as an emergent phenomenon. [ABSTRACT FROM AUTHOR]

This paper was designed and prepared a new nanoarchitectonics of LDH/polymer composite with specific morphology. For this purpose, CTAB surfactant was used to control the morphology of layered double hydroxide (LDH) and to prepare LDH/polymer nanocomposites (LDH–APS–PEI–DTPA). The polymer was synthesized using diethylenetriaminepentaacetic acid (DTPA), polyethylenimine and used with LDH to form a nanocomposite with high thermal stability. Subsequently, the prepared nanocomposite was identified using FTIR, EDX, TGA, XRD, FESEM, and BET techniques. In addition, the prepared LDH–APS–PEI–DTPA nanocomposite was used as a heterogeneous and recyclable catalyst for the synthesis of imidazole derivatives under green conditions. The results showed that the LDH–APS–PEI–DTPA nanocomposite benefit from suitable morphology, simple preparation, high catalytic activity, and high surface area. Also, the proposed LDH–APS–PEI–DTPA heterogeneous catalyst showed high stability and reusability for five consecutive runs which was consistent with the principles of green chemistry. [ABSTRACT FROM AUTHOR]