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A major challenge in upscaling and commercializing dye-sensitized solar cells (DSSC) is to simultaneously rely on a robust photoconversion efficiency (PCE) along with long-term device stability. Two-dimensional (2D) nanocarbon materials are known to improve the PCE and stability of devices made of hybrid nanocomposite photoanodes. However, there is inadequate knowledge on how the morphology of 2D nanocarbon materials plays an important role in improving photovoltaic (PV) performance and stability. Here we report the comparative effect on the PV performance and the long-term stability of DSSCs made of optimal loadings of few-layer graphene (FLG) flakes and graphene nanoribbons (GNR) into the mesoporous TiO₂ active layer. DSSCs were fabricated by using standard nanocrystalline TiO₂, GNR-TiO₂ and FLG-TiO₂ hybrid mesoporous films as anodes and subjected to continuous visible light irradiation to monitor their long-term stability. Results show that the optimized incorporation of GNR (0.005 wt%) and FLG (0.010 wt%) in the mesoporous TiO₂ active layer enhances the PCE by 34% and 21% compared to pristine TiO₂, respectively. Moreover, the operational stability of hybrid devices shows a 51.6% (for GNR-TiO₂) and a 10% (for FLG-TiO₂) sustained higher PCE than the device based on bare TiO₂, after 273 h of continuous one sunlight soaking. The electrochemical impedance spectroscopy (EIS) and transient photovoltage decay were studied to investigate how GNR strikingly reduces degradation of device performance as compared to its counterpart FLG-TiO₂ and TiO₂ based cells. This significant enhancement can be attributed to the structural modifications induced by GNR within the TiO₂ photoanode, which improves the electron lifetime and reduces non-radiative carrier recombination.

Human dopamine transporter gene (SLC6A3) is one of the neurotransmission genes that plays an important role in controlling the behavior and psychological reactions toward various physical activities. The aim of the present study is to evaluate the associations between SLC6A3 3’-UTR VNTR (3’VNTR) genotypes and eight personality traits in Egyptian athletes. One hundred athletes (50 males and 50 females) and one hundred non-athletes participated in this investigation either in individual or team games. The Freiburg Personality inventory-Revised questionnaire was applied to athletes to evaluate personality traits according to the scale, at a scheduled time, using descriptive analysis. Genotyping for SLC6A3 3’-UTR VNTR polymorphism in athletes was realized to detect the different genotypes by PCR amplifications using desired primers. Three different genotypes of the 3’VNTR polymorphism; namely (9/9), (9/10), (10/10) were identified. The 9/10 and 10/10 genotypes of SLC6A3 gene were significantly higher in players than those in the control group. There were no statistically significant differences in personality traits values among males and females. The Cronbach’s alpha stability coefficient for four items is higher than 0.7 suggesting that these items (Neuroticism, Aggressiveness, Depression and Excitability) have a good reliability and support the used personality dimensions for this investigation. Our findings revealed a significant association between the genotypes of 3’VNTR and the personality traits in Egyptian athletes. These data shed light on the role of SLC6A3 gene in athletes’ behavioral performance and could serve as the basis for further characterization in the large number of Egyptian athletes.

In Taiwan, the digitalization of banks has imparted a future trend and a national financial technology (FinTech) policy. This paper aims to study which factors will affect the promotion of digital banking amongst digital accounts. Categorically, we applied the principal components analysis (PCA) method to analyze and identify the main factors of digital banking development. In addition, this study used three years of data from 2017 to 2020 since the data were relatively comprehensive and included all the large financial holding companies (15 in total) in Taiwan. The empirical findings can briefly be summarized as follows: a bank that wants to promote digital accounts must start with a credit card since that is what digital finance must be bound to. They also need to let people know that digital accounts have many advantages, such as no deposit limits or interest-free cross-bank withdrawals. There are a few crucial factors that need to be considered, including the number of free transfers, the card in force, active cards, and the number of free withdrawals. If banks effectively promote and attract people to apply for digital accounts, it could strongly contribute to the development of digital banking in Taiwan. JEL classification numbers: C45, G10. Keywords: Financial technology, Digital banking, Digital account, Principal components analysis.

Lignin is a potential resource for biobased aromatics with applications in the field of fuel additives, resins, and bioplastics. Via a catalytic depolymerization process using supercritical ethanol and a mixed metal oxide catalyst (CuMgAlOx), lignin can be converted into a lignin oil, containing phenolic monomers that are intermediates to the mentioned applications. Herein, we evaluated the viability of this lignin conversion technology through a stage-gate scale-up methodology. Optimization was done with a day-clustered Box-Behnken design to accommodate the large number of experimental runs in which five input factors (temperature, lignin-to-ethanol ratio, catalyst particle size, catalyst concentration, and reaction time) and three output product streams (monomer yield, yield of THF-soluble fragments, and yield of THF-insoluble fragments and char) were considered. Qualitative relationships between the studied process parameters and the product streams were determined based on mass balances and product analyses. Linear mixed models with random intercept were employed to study quantitative relationships between the input factors and the outcomes through maximum likelihood estimation. The response surface methodology study reveals that the selected input factors, together with higher order interactions, are highly significant for the determination of the three response surfaces. The good agreement between the predicted and experimental yield of the three output streams is a validation of the response surface methodology analysis discussed in this contribution.