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G-quadruplexes (G4) are non-canonical, four-stranded, nucleic acid secondary structures formed in the guanine-rich sequences, where guanine nucleotides associate with each other via Hoogsteen hydrogen bonding. These structures are widely found near the functional regions of the mammalian genome, such as telomeres, oncogenic promoters, and replication origins, and play crucial regulatory roles in replication and transcription. Destabilization of G4 by various carcinogenic agents allows oncogene overexpression and extension of telomeric ends resulting in dysregulation of cellular growth–promoting oncogenesis. Therefore, targeting and stabilizing these G4 structures with potential ligands could aid cancer prevention and therapy. The field of G-quadruplex targeting is relatively nascent, although many articles have demonstrated the effect of G4 stabilization on oncogenic expressions; however, no previous study has provided a comprehensive analysis about the potency of a wide variety of nutraceuticals and some of their derivatives in targeting G4 and the lattice of oncogenic cell signaling cascade affected by them. In this review, we have discussed bioactive G4-stabilizing nutraceuticals, their sources, mode of action, and their influence on cellular signaling, and we believe our insight would bring new light to the current status of the field and motivate researchers to explore this relatively poorly studied arena. Schematic diagram depicting nutraceuticals' role in attenuating cancer progression [ABSTRACT FROM AUTHOR]

Using composite methods of quantum chemical calculations and the atomization method, the values of the enthalpy of formation for a test set of 79 compounds in gas phase have been calculated with accuracy of 3.8, 4.5, and 4.7 kJ/mol for the G4, G4MP2, and CBS-QB3 methods, respectively. According to the results of statistical analysis of deviations of theoretical values from experimental ones, the presence of an error occurring at the geometry optimization step due to neglected correlation effects has been revealed. For aliphatic amines and alcohols from the considered set of compounds, the values of the pKa for aqueous solutions have been calculated using the G4 method including solvent effects according to the CPCM model. The existence of a correlation between the error in the pKa calculation and the differences in energy values between the highest occupied and lowest unoccupied molecular orbitals for conjugated acid and base forms in the solution phase has been revealed. A method has been suggested to refine the calculation results, using which the pKa values for 20 amines and 20 alcohols have been determined with accuracy of 0.67 and 0.87 pKa units, respectively. [ABSTRACT FROM AUTHOR]

The study aims to show the impact of financial knowledge among rural consumers' access to financial technology services. In general, knowledge regarding any particular fact helps consumers to select or reject different options. Therefore, knowledge regarding financial services is considered a factor that influences access to financial technology services. This study carries out a survey-oriented method with a structured questionnaire. According to the data category, this study uses three well-known econometric models: logistic regression, probit regression, and complementary log–log regression, have been experimented. This study finds that knowledge regarding various factors significantly impact on access to financial technology services. Mainly, this study has important practical significance for the use of rural finance and financial technology in rural areas, which affects the entire economy. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the growth response of G4 transgenic mutiara catfish reared at different stocking densities. The relative expression ratio levels of CgGH/ß-actin and IGF-1/ß-actin mRNA was measured using quantitative real-time PCR (qRT-P CR) in G4 mutiara catfish. Fish were kept for 8 weeks at different stocking densities (treatment A, 15 fish/100 L; B, 12 fish/100 L; C, 10 fish/100 L for transgenic fish; and A*, 15 fish/100 L for non-transgenic fish). The average increase in body weight of G4 mutiara catfish was 1.9–2.3 times higher compared to non-transgenic mutiara catfish at the same stocking densities. The growth response indicates an overexpression of the growth hormone (GH) in G4 mutiara catfish, displaying expression levels 1.3–2.9 higher than in non-transgenic fish. The use of high stocking density (treatment A, 15 fish/100 L) induced overexpression of the exogenous GH (CgGH) and increased the body protein content, as well as improved the feed conversion ratio, protein retention value, and fish protein efficiency ratio, leading to faster body weight gain of G4 transgenic versus non-transgenic mutiara catfish. The growth of G4 catfish in treatments B and C remained higher than in treatment A* (non-transgenic fish), but the growth of non-transgenic catfish was slower. The induction of the CgGH expression level caused an increase in the growth, protein retention, protein efficiency ratio, and IGF-1 expression level of G4 transgenic mutiara catfish. The permanent inheritance of CgGH in G4 fish has the potential to increase the mass production of commercial catfish culture. [ABSTRACT FROM AUTHOR]

Cell metabolism depends, to a large extent, on correct regulation of gene expression. One of the mechanisms of regulation is the formation of nucleic acid secondary structures, among which guanine quadruplexes (G-quadruplexes, or G4) are of particular importance. G-quadruplexes are dynamic structures whose stability is determined by their size, ionic composition, and the nature of the nucleic acids forming them. They are regulated by various protein factors. Guanine quadruplexes play an important role in the regulation of many processes occurring in DNA and RNA, from maintaining telomere homeostasis to determining the ribosome landing site on mRNA. Therefore, these structures are considered a promising target for antitumor therapy, and their detailed study is important to modern biology. This review is focused on the structure and thermodynamic properties of G-quadruplexes together with their interaction with some nuclear proteins. [ABSTRACT FROM AUTHOR]

This study attempts to examine the adaptive market hypothesis and evolving predictability of stock returns using four decades of daily data from the Bombay Stock Exchange (BSE) and the National Stock Exchange (NSE) in India. The recent developed automatic portmanteau ratio (AVR) and wild bootstrap automatic variance ratio (WAVR) test are used for analysis. We also estimate both the AVR and WAVR statistics in the rolling window framework to examine evolving predictability. The results revealed that BSE and NSE are informationally inefficient in the weak-form. The results of rolling window analysis suggested that the degree of predictable patterns evolves over the period due to global and regional economic and non-economic events. Further, the study compare which stock market is more efficient and found that NSE is more efficient than BSE. The findings of this study provide essential inputs to investors on trading strategies in dynamic economic situations and policymakers to formulate an appropriate policy that can make the Indian stock markets efficient. [ABSTRACT FROM AUTHOR]

This paper explores the role of sentiment in style investing for a sample of eight Eurozone markets and makes a distinction between fundamentals-driven sentiment and sentiment based on non-fundamental information. The findings indicate that style portfolio returns are statistically and economically significant, however, their return differential is not. Style portfolio returns are sensitive to changes in sentiment with value portfolios exhibiting higher sensitivity, and sentiment variance explains a significant percentage of style portfolio return variance. For example, for Germany during the US financial crisis the variance of fundamentals-driven sentiment accounts for 19.65% of the value portfolio variance and the variance of non-fundamental sentiment for a further 24.67%. The results are robust to the choice of valuation ratios in defining investment style. Finally, style portfolio returns tend to be higher, on average, during optimistic months (high sentiment), for the majority of the markets. For instance, during the US crisis, when high non-fundamental sentiment prevails, for five northern Eurozone markets, value portfolio monthly returns range between 2.54 and 3.87%. [ABSTRACT FROM AUTHOR]

In this paper, we employ the Heston stochastic volatility model to describe the stock's volatility and apply the model to derive and analyze trading strategies for dealers in a security market with price discovery. The problem is formulated as a stochastic optimal control problem, and the controlled state process is the dealer's mark-to-market wealth. Dealers in the security market can optimally determine their ask and bid quotes on the underlying stocks continuously over time. Their objective is to maximize an expected profit from transactions with a penalty proportional to the variance of cumulative inventory cost. We provide an approximate, analytically tractable solution to the stochastic control problem. Numerical experiments are given to illustrate the effects of various parameters on the performances of trading strategies. [ABSTRACT FROM AUTHOR]

Based upon my experience in research, teaching, writing textbooks, and editing handbooks and journals, this review paper discusses how financial econometrics, mathematics, statistics, and financial technology can be used in research and teaching for students majoring in quantitative finance. A major portion of this paper discusses essential content of Lee and Lee (Handbook of financial econometrics, mathematics, statistics, and machine learning, World Scientific, Singapore, 2020). Then Lee (From east to west: memoirs of a finance professor on academia, practice, and policy, World Scientific, Singapore, 2017), Lee et al. (Financial econometrics, mathematics and statistics, Springer, New York, 2019a; Machine learning for predicting default of credit card holders and success of kickstarters. Working paper, 2019b), and Lee and Lee (Handbook of financial econometrics and statistics, Springer, New York, 2015) are used to enhance the content of this paper. In addition, important and relevant papers, which have been published in different journals are also used to support the issues discussed in this paper. I have found the applications of financial econometrics, mathematics, statistics, and technology have improved drastically over the last five decades. Therefore, both practitioners and academicians need to update their skills in this area to compete in both financial market and academic research. [ABSTRACT FROM AUTHOR]

Although methyl transfer reactions are important in both chemical and biological systems, there is a need for thermodynamic parameters related to methyl affinity and O–CH3 bond dissociation enthalpies (BDEs) relevant to a full understanding of the mechanisms of methyl transfer reactions. As a prelude to the construction of a database of O–CH3 BDEs, the present work examines the reliability of a series of theoretical methods for the prediction of O–CH3 BDEs using a set of 25 compounds that included both aromatic and non-aromatic molecules. The BDEs calculated by density functional theory (DFT) with traditional exchange–correlation functions exhibited much larger errors than those obtained by either the M06-2X or G4 methods. For the non-aromatic compounds, M06-2X/def2-TZVP performed slightly better than G4, but G4 was more accurate for the aromatic molecules. As a result, we recommend G4 as the preferred method for the theoretical estimation of O–CH3 bond dissociation enthalpies, although M06-2X may be a good alternative for large complex molecules when the use of G4 is impractical. [ABSTRACT FROM AUTHOR]

We document how online lenders exploit a flawed, new pricing mechanism in a peer-to-peer lending platform: Prosper.com. Switching from auctions to a posted-price mechanism in December 2010, Prosper assigned loan listings with different estimated loss rates into seven distinctive rating grades and adopted a single price for all listings with the same rating grade. We show that lenders adjusted their investment portfolios towards listings at the low end of the risk spectrum of each Prosper rating grade. We find heterogeneity in the speed of adjustment by lender experience, investment size, and diversification strategies. It took about 16–17 months for an average lender to take full advantage of the "cherry-picking" opportunity under the single-price regime, which is roughly when Prosper switched to a more flexible pricing mechanism. [ABSTRACT FROM AUTHOR]

We conduct a series of experiments to examine the effects of the make and take fee structure currently used by equity exchanges in the U.S. We examine the effects of these fees on measures of market quality (efficiency, book depth, and the bid-ask spread). We find spreads to be smaller in the presence of make and take fees, and we note that this fee structure seems to induce buyers (moreso than sellers) to compete for rebates from the exchange leading to higher prices and lower profits. To test whether our results are due to the make and take fee structure or are artefacts of trading fees in general, we performed a second set of experiments in which traders on both sides of a transaction were assessed an identical fee. These identical trading fees do not appear to significantly affect our market quality measures. [ABSTRACT FROM AUTHOR]

In recent years, thematic exchange-traded funds (ETF) have increased in economic significance. Investors in thematic ETFs have more than just financial objectives and gain a non-monetary added value from a thematic portion in their portfolios. Therefore, traditional portfolio optimization models which target only financial criteria cannot suit these investors' needs anymore. Nevertheless, to account for their thematic interests, investors adapt a core satellite strategy in which conventional core portfolios and thematic satellite portfolios are combined. Thus, these portfolios are separately optimized without further considering inter-portfolio correlation effects. Since modern portfolio theory has originally been established to, inter alia, optimize these correlation effects, portfolios can only be efficient by chance. Therefore, this study targets the correlation effects between conventional and thematic portfolios and uses a tri-criterion thematic portfolio optimization model as an overall framework. Throughout a two-part analysis with tradable ETFs and a simulation with 250,000 draws and 1,750,000 portfolio optimizations performed, the status quo is compared to the tri-criterion model. Quantifying the suboptimality, simulation results show a mean portfolio improvement of 6.23% measured as relative yield enhancement. Further, our analysis concludes that the more narrowly a theme is defined and the more particular it is, relative yield enhancements can increase up to 46.88%. [ABSTRACT FROM AUTHOR]

We evaluate monetary policy divergence in the G4. A Taylor rule is extended that admits a global element and also allows for unconventional monetary policy to be reflected in a shadow policy rate. We propose a policy divergence index based on observed, fitted, or shadow policy rates but which interprets the stance of monetary as dictated by the real interest rate. In spite of flexible exchange rates, each economy's monetary policy is significantly impacted by a global element, pre and post-crisis. Our divergence index also suggests more divergence in the stance of monetary policy than if nominal policy rates alone are compared, whether observed or shadow rates are used. Nevertheless, we conclude that US monetary policy's impact among other systemically important economies has increased since the global financial crisis although divergences persist. [ABSTRACT FROM AUTHOR]

We define quality as characteristics that investors should be willing to pay a higher price for. Theoretically, we provide a tractable valuation model that shows how stock prices should increase in their quality characteristics: profitability, growth, and safety. Empirically, we find that high-quality stocks do have higher prices on average but not by a large margin. Perhaps because of this puzzlingly modest impact of quality on price, high-quality stocks have high risk-adjusted returns. Indeed, a quality-minus-junk (QMJ) factor that goes long high-quality stocks and shorts low-quality stocks earns significant risk-adjusted returns in the United States and across 24 countries. The price of quality varies over time, reaching a low during the internet bubble, and a low price of quality predicts a high future return of QMJ. Analysts' price targets and earnings forecasts imply systematic quality-related errors in return and earnings expectations. [ABSTRACT FROM AUTHOR]

This article is the first one to examine the moderating role of bitcoin sentiment indices on the short term and long-term time–frequency-based good and bad network connectedness of all US sectors. In more detail, the paper quantifies the above relationship between the 11 US sectoral high frequency returns and then identifies the moderating impact of bitcoin investors’ fear and greed sentiment on good and bad network connectedness during pre-Covid-19 and Covid-19. For the said purpose, we decompose the returns into good and bad volatility, and rely on time and frequency dependent spillover measures and quantify a spillover symmetrical and asymmetrical measure for network connectedness for different investment horizons. Furthermore, we also quantify the NET good–bad volatility transmission and reception capability of all our sectors within the frequency dependent network. The extracted good and bad network connectedness indices are then regressed on multiple thresholds of bitcoin sentiment indices. Quantile regression results revealed that fear, extreme fear, greed and extreme greed moderate the short term and long term good and bad volatility spillovers within the network connectedness. Finally, we also utilize hedge ratios and optimal portfolio weight selection strategies to explain whether short positioning in the US sectoral returns can be used to hedge against bitcoin sentiment risk. [ABSTRACT FROM AUTHOR]

The underlying hypothesis is that there are significant abnormal returns during the 10 days (the window of analysis established within the event studies literature) before and after the last federal minimum wage change for major companies that employ minimum wage workers. They found little change in the stock prices of firms employing large numbers of minimum wage workers. Event study methodology was also used by Farber & Hallock ( I Cornell University Center for Advanced Human Resource Studies Working Paper i , 2007) to study the reaction of stock prices to announcements of reductions in labor force. [Extracted from the article]

REIT characteristics pose unique risks and benefits to investors who seek liquid diversification and hedging vehicles to complement their portfolios. This paper tests for the asymmetric effect of individual and institutional investor sentiment on REIT industry returns and conditional volatility. We simultaneously model the impact of two markedly different groups of investors on the return generating process of the REIT industry. Our findings suggest that noise trading imposes significant systemic risk on the realization of REIT industry returns. Interestingly, corrections in institutional investor expectations have a larger effect on REIT industry returns and volatility than changes in individual investor expectations. More specifically, bearish shifts in institutional investor expectations of future market conditions have a significantly larger impact on returns and volatility than bullish shifts. Results align with the overreaction to negative information and loss aversion hypotheses. [ABSTRACT FROM AUTHOR]

Is a firm that is known for positively engaging stakeholders expected to voluntarily disclose bad financial news? If it makes the announcement, does its corporate goodness help to mitigate the stock price reaction? We examine these issues using a sample of profit warnings, and a sample of firms with negative earnings surprises that did not warn. Firms that have positive corporate social responsibility ratings are more likely to provide earnings warnings than other firms. When they do provide a profit warning, the event negative abnormal returns are of significantly smaller magnitude than the returns of other firms providing warnings. This effect does not occur for social firms that decide not to warn. They suffer the same negative stock price impact on the earnings announcement day as other firms. [ABSTRACT FROM AUTHOR]

The geometries, electronic structures and energies of small ScSi species ( n = 1−6) and their anions have been systematically investigated by means of the higher level of the ccCA-TM, G4, and G4(MP2) schemes. The global minima of these clusters have been presented. The global minima of neutral ScSi ( n = 1-6) and their anions are 'substitutional structure' which is derived from Si by replacing a Si atom with a Sc atom. The adiabatic electron affinities for ScSi have been estimated. Compared with limited experimental data, the average absolute deviations from experiment for ccCA-TM, G4, and G4(MP2) are 0.21 eV, 0.22 eV, and 0.25 eV, respectively. The dissociation energies of Sc atom from the lowest-energy structure of ScSi clusters have been evaluated to examine relative stabilities. The electron affinities and dissociation energies predicted by ccCA-TM, G4, and G4(MP2) methods, especially for ccCA-TM and G4, differ little from each other. The agreement may indicate they are reliable. [ABSTRACT FROM AUTHOR]

We have computed the Gaussian G4 structures, enthalpies of formation, and Gibbs free energies of formation of four trans-1,2-dialkylcyclopentanes. Aside from their intrinsic interest as products of petroleum refining, we wish to use these simple trans-1,2-dialkylcyclopentanes as a database in the study of larger, more complicated molecules like prostanoic acid and its derivatives, the prostaglandins. [ABSTRACT FROM AUTHOR]