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Item Methylation Level Differences between the Housekeeping and the Specialized Genes Identified during Ontogenesis(B P International, 2022-12-01) Pinsky, Eugene; Goldberg, Saveli; Sukumaran, Parvathy; Salnikov, Lev; Hanif, AsmaThe genome methylation is one of the leading areas in the study of aging. The theoretical model we proposed earlier explains aging by redistribution of limited resources between two main tasks of the organism: its self-sustenance based on the function of the housekeeping gene group (HG) and functional differentiation provided by the IntG integrative gene group. To test our model, we used methylation level data of 100 genes, (gene body and its promoter) of 50 in the HG group and 50 in IntG. We found reliable differences ( p<0.0001) between our groups in the level of absolute methylation values, more pronounced in the promoters of the studied genes. We showed their significant decrease in IntG with age in contrast to HG, where this level remained relatively constant. The decrease in methylation in the IntG group is indirectly confirmed by the analysis of data variance, which also decreased in the genes of this group. The increasing imbalance between HG and IntG by methylation levels suggests that this IntG-shift reflects a side effect of the ontogenesis program and its connection to the main cause of aging.Item DNA methylation meta-analysis confirms the division of the genome into two functional groups(2022-05-16) Pinsky, Eugene; Salnikov, Lev; Sukumaran, Parvathy; Goldberg, SaveliBased on a meta-analysis of human genome methylation data, we tested a theoretical model in which aging is explained by the redistribution of limited resources in cells between two main tasks of the organism: its selfsustenance based on the function of the Housekeeping Gene Group (HG) and functional differentiation, provided by the (IntG) integrative gene group. A meta-analysis of methylation of 100 genes, 50 in the HG group and 50 in IntG, showed significant differences (p<0.0001) between our groups in the level of absolute methylation values of genes bodies and its promoters. We showed a reliable decrease of absolute methylation values in IntG with rising age in contrast to HG, where this level remained constant. The one-sided decrease in methylation in the IntG group is indirectly confirmed by the dispersion data analysis, which also decreased in the genes of this group. The imbalance between HG and IntG in methylation levels suggests that this IntG-shift is a side effect of the ontogenesis grownup program and the main cause of aging. The theoretical model of functional genome division also suggests the leading role of slow dividing and post mitotic cells in triggering and implementing the aging process.Item Constructing portfolios using stable distributions: the case of S&P 500 sectors exchange-traded funds(Elsevier BV, 2022-12) Vasiukevich, Andrei; Pinsky, EugenePortfolio construction is an important practical problem in finance. In the traditional approach, introduced by Markowitz, one assumes normally distributed returns and constructs a portfolio with a minimum risk (measured by the standard deviation of portfolio returns) for a specified (and minimally acceptable) return. In practice, returns are not normally distributed and have heavy tails. As a result, the normality assumption severely underestimates risk. It has been long suggested that a more appropriate way is to model returns by using alpha-stable distributions. In this paper, we use elliptical stable distributions for optimal stable portfolio construction. We illustrate this by considering portfolios from S&P 500 sector exchange-traded funds (ETFs). Our main results indicate that stable portfolios are in general comparable with standard Markowitz portfolios. But we discovered a few properties of stable distributions that are promising for optimal portfolio selection problem. Stable risk estimation for next year is much closer to the actual portfolio risk, stable portfolios are more balanced, so they better handle maximum restriction on component weights, and stable portfolios are more resilient to extreme market conditions. Both stable and normal optimal portfolios outperform S&P 500 index and equally-weighted ETF portfolio in most years. We propose an investment strategy that uses both stable and normal distributions for building optimal portfolios. The return of this strategy exceeds the return of the strategies which use only stable or only normal distributions.Item A clustering-based approach to automatic harmonic analysis: an exploratory study of harmony and form in Mozart’s piano sonatas(Ubiquity Press, Ltd., 2022-10-13) Yust, Jason; Lee, Jaeseong; Pinsky, EugeneWe implement a novel approach to automatic harmonic analysis using a clustering method on pitch-class vectors (chroma vectors). The advantage of this method is its lack of top-down assumptions, allowing us to objectively validate the basic music theory premise of a chord lexicon consisting of triads and seventh chords, which is presumed by most research in automatic harmonic analysis. We use the discrete Fourier transform and hierarchical clustering to analyse features of the clustering solutions and illustrate associations between the features and the distribution of clusters over sections of the sonata forms. We also analyse the transition matrix, recovering elements of harmonic function theory.Item A critical bioenergetic switch is regulated by IGF2 during murine cartilage development(Springer Science and Business Media LLC, 2022-11-11) Hollander, Judith M.; Li, Lingyun; Rawal, Miraj; Wang, Si Kun; Shu, Yue; Zhang, Ming; Nielsen, Heber C.; Rosen, Clifford J.; Zeng, LiLong bone growth requires the precise control of chondrocyte maturation from proliferation to hypertrophy during endochondral ossification, but the bioenergetic program that ensures normal cartilage development is still largely elusive. We show that chondrocytes have unique glucose metabolism signatures in these stages, and they undergo bioenergetic reprogramming from glycolysis to oxidative phosphorylation during maturation, accompanied by an upregulation of the pentose phosphate pathway. Inhibition of either oxidative phosphorylation or the pentose phosphate pathway in murine chondrocytes and bone organ cultures impaired hypertrophic differentiation, suggesting that the appropriate balance of these pathways is required for cartilage development. Insulin-like growth factor 2 (IGF2) deficiency resulted in a profound increase in oxidative phosphorylation in hypertrophic chondrocytes, suggesting that IGF2 is required to prevent overactive glucose metabolism and maintain a proper balance of metabolic pathways. Our results thus provide critical evidence of preference for a bioenergetic pathway in different stages of chondrocytes and highlight its importance as a fundamental mechanism in skeletal development.Item Smartphone-based neuropsychological assessment in Parkinson's disease: feasibility, validity, and contextually driven variability in cognition(Cambridge University Press (CUP), 2022-04) Weizenbaum, Emma L.; Fulford, Daniel; Torous, John; Pinsky, Emma; Kolachalama, Vijaya B.; Cronin-Golomb, AliceOBJECTIVES: The prevalence of neurodegenerative disorders demands methods of accessible assessment that reliably captures cognition in daily life contexts. We investigated the feasibility of smartphone cognitive assessment in people with Parkinson's disease (PD), who may have cognitive impairment in addition to motor-related problems that limit attending in-person clinics. We examined how daily-life factors predicted smartphone cognitive performance and examined the convergent validity of smartphone assessment with traditional neuropsychological tests. METHODS: Twenty-seven nondemented individuals with mild-moderate PD attended one in-lab session and responded to smartphone notifications over 10 days. The smartphone app queried participants 5x/day about their location, mood, alertness, exercise, and medication state and administered mobile games of working memory and executive function. RESULTS: Response rate to prompts was high, demonstrating feasibility of the approach. Between-subject reliability was high on both cognitive games. Within-subject variability was higher for working memory than executive function. Strong convergent validity was seen between traditional tests and smartphone working memory but not executive function, reflecting the latter's ceiling effects. Participants performed better on mobile working memory tasks when at home and after recent exercise. Less self-reported daytime sleepiness and lower PD symptom burden predicted a stronger association between later time of day and higher smartphone test performance. CONCLUSIONS: These findings support feasibility and validity of repeat smartphone assessments of cognition and provide preliminary evidence of the effects of context on cognitive variability in PD. Further development of this accessible assessment method could increase sensitivity and specificity regarding daily cognitive dysfunction for PD and other clinical populations.Item Plagiarism abatement with assignment templates(Springer, 2022-11-07) Braude, Eric; Polnar, JackThe ubiquity of plagiarism sites has made it imperative that faculty change assignments every time they teach a course. However, this can be very time consuming. We describe a way to make such changes that consumes a reasonable amount of time and also enhances students’ learning.Item Neuromarketing’s socioeconomic status and racial discrimination and lack of transparency(Research Publishing Academy, 2022-12-31) Goncalves, Marcus; Luther, Valorie; Hayes, SydneyNeuromarketing, the scientific study of the nervous system applied to marketing, is evolving rapidly. Marketers recognize that brain and biometric studies lead to a deeper understanding of consumer preferences. This research provides a historically accurate timeline of significant discoveries and a review of present-day neuromarketing tools and corporate case studies. A systematic methodological review was conducted, and findings were synthesized using secondary peer-reviewed research, media reports, and academic studies by marketing associations. This study shows that this area of neuroscience has challenges due to a lack of transparency, minimal standardization, and little to no corroboration among scientists. Additionally, neuromarketing researchers may not address the effects of racism and socioeconomic status on the brain, which, if not considered, can render the sampling results incomplete. With multinational corporations driving the demand for neuromarketing, attaining reliable data from a diverse and robust cross-section of subjects should be prioritized.Item Neuromarketing and global branding reaction analysis based on real-time monitoring of multiple consumer's biosignals and emotions(2022-11-11) Goncalves, MarcusConsumers' selections and decision-making processes are some of the most exciting and challenging topics in neuromarketing, sales, and branding. Multicultural influences and societal conditions are also crucial to consider from a global perspective. Applying neuroscience tools and techniques in international marketing and consumer behavior is an emergent and multidisciplinary field that aims to understand consumers' thoughts, reactions, and selection processes in branding and sales. This study focuses on real-time monitoring of different physiological signals using eye-tracking, facial expressions recognition, and Galvanic Skin Response (GSR) acquisition methods to analyze consumers' responses, detect emotional arousal, measure attention or relaxation levels, analyze perception, consciousness, memory, learning, motivation, preference, and decision-making. The primary purpose of this research was to monitor human subjects' reactions to these signals during an experiment designed in three phases consisting of different types of branding advertisements. The non-advertisement exposition was also monitored while gathering survey responses at the end of each phase. A feature extraction module was implemented with a data analytics module to calculate statistical metrics and decision-making supporting tools based on Principal Component Analysis (PCA) and Feature Importance (FI) determination based on the Random Forest technique. The results indicate that when compared to image ads, video ads are more effective in attracting consumers' attention and creating more emotional arousal.Item Internationalization strategies of Lusophone-African SMEs: a case study analysis(2022-11-06) Goncalves, MarcusThis study investigates Lusophone Africa multi-national enterprises (MNEs) internationalization strategies from Angola and Mozambique, specifically their entry mode. Information was gathered through a survey of 29 MNE’s upper management respondents and subsequent face-to-face semi-structured interviews with 24 of them in their countries. The results suggest that most MNEs opted for equity-based investment strategies, mainly joint ventures and mergers and acquisitions (M&A), as their preferred mode of entry when internationalizing. A significant group opted for e-commerce/e-business strategies and direct and indirect exports. A smaller portion of the interviewees chose Greenfield investment as a mode of entry. These MNEs could be classified as born global/international new ventures (INV). Finally, this study presents a conceptual framework for studying the entry mode choice of enterprises from Lusophone Africa frontier markets. It presents research propositions for better understanding the determinants of entry mode strategies of enterprises from Angola and Mozambique. Case study analysis of internationalization strategies of Lusophone-African SMEs in Angola and Mozambique. A proposal of an integrated internationalization approach.Item Analysis of cryptocurrency dependencies(2021-04-30) Todorovska, Ana; Spirovska, Eva; Angelovski, Gorast; Peshov, Hristijan; Rusevski, Ivan; Marojevikj, Jovana; Vodenska, Irena; Chitkushev, Lubomir T.; Trajanov, DimitarIn a world where no country, market, or economy is an island, interconnectivity is becoming a fundamental feature of almost all social and economic systems. In the case of digital assets like cryptocurrencies, the impact of interconnectivity on their performance and price trajectory is amplified. Studying these phenomena is essential for understanding the processes driving the crypto-markets. In this paper, we propose seven different approaches to create a network of eighteen most important cryptocurrencies. The first three approaches discover correlations between cryptocurrencies based on their daily prices, daily returns, and sentiment extracted from Reddit data. The following two approaches offer insights from the frequency of joint appearance of cryptocurrencies in Google news and Reddit data. The remaining two approaches determine each cryptocurrency’s impact over the others when forecasting prices and returns. Furthermore, we explore the networks’ interdependencies to explore the similarities of the cryptocurrency networks generated by different approaches. The proposed methodology allows us to understand the dynamics in the cryptocurrency markets and the different processes that influence their performance.Item Mitigation of cascading failures in complex networks(2020-09-30) Smolyak, Alex; Levy, Orr; Vodenska, Irena; Buldyrev, Sergey V.; Havlin, ShlomoCascading failures in many systems such as infrastructures or financial networks can lead to catastrophic system collapse. We develop here an intuitive, powerful and simple-to-implement approach for mitigation of cascading failures on complex networks based on local network structure. We offer an algorithm to select critical nodes, the protection of which ensures better survival of the network. We demonstrate the strength of our approach compared to various standard mitigation techniques. We show the efficacy of our method on various network structures and failure mechanisms, and finally demonstrate its merit on an example of a real network of financial holdings.Item Systemic stress test model for shared portfolio networks(2021-02-08) Vodenska, Irena; Dehmamy, Nima; Becker, Alexander P.; Buldyrev, Sergey V.; Havlin, ShlomoWe propose a dynamic model for systemic risk using a bipartite network of banks and assets in which the weight of links and node attributes vary over time. Using market data and bank asset holdings, we are able to estimate a single parameter as an indicator of the stability of the financial system. We apply the model to the European sovereign debt crisis and observe that the results closely match real-world events (e.g., the high risk of Greek sovereign bonds and the distress of Greek banks). Our model could become complementary to existing stress tests, incorporating the contribution of interconnectivity of the banks to systemic risk in time-dependent networks. Additionally, we propose an institutional systemic importance ranking, BankRank, for the financial institutions analyzed in this study to assess the contribution of individual banks to the overall systemic risk.Item Relationship between macroeconomic indicators and economic cycles in U.S.(2020-05-21) Iyetomi, Hiroshi; Aoyama, Hideaki; Fujiwara, Yoshi; Souma, Wataru; Vodenska, Irena; Yoshikawa, HiroshiWe analyze monthly time series of 57 US macroeconomic indicators (18 leading, 30 coincidental, and 9 lagging) and 5 other trade/money indexes. Using novel methods, we confirm statistically significant co-movements among these time series and identify noteworthy economic events. The methods we use are Complex Hilbert Principal Component Analysis (CHPCA) and Rotational Random Shuffling (RRS). We obtain significant complex correlations among the US economic indicators with leads/lags. We then use the Hodge decomposition to obtain the hierarchical order of each time series. The Hodge potential allows us to better understand the lead/lag relationships. Using both CHPCA and Hodge decomposition approaches, we obtain a new lead/lag order of the macroeconomic indicators and perform clustering analysis for positively serially correlated positive and negative changes of the analyzed indicators. We identify collective negative co-movements around the Dot.com bubble in 2001 as well as the Global Financial Crisis (GFC) in October 2008. We also identify important events such as the Hurricane Katrina in August 2005 and the Oil Price Crisis in July 2008. Additionally, we demonstrate that some coincidental and lagging indicators actually show leading indicator characteristics. This suggests that there is a room for existing indicators to be improved.Item Socio-economic impact of the Covid-19 pandemic(2020-12-15) Barlow, Jonathan; Vodenska, IrenaThis paper proposes a dynamic cascade model to investigate the systemic risk posed by sector-level industries within the U.S. inter-industry network. We then use this model to study the effect of the disruptions presented by Covid-19 on the U.S. economy. We construct a weighted digraph G = (V,E,W) using the industry-by-industry total requirements table for 2018, provided by the Bureau of Economic Analysis (BEA). We impose an initial shock that disrupts the production capacity of one or more industries, and we calculate the propagation of production shortages with a modified Cobb–Douglas production function. For the Covid-19 case, we model the initial shock based on the loss of labor between March and April 2020 as reported by the Bureau of Labor Statistics (BLS). The industries within the network are assigned a resilience that determines the ability of an industry to absorb input losses, such that if the rate of input loss exceeds the resilience, the industry fails, and its outputs go to zero. We observed a critical resilience, such that, below this critical value, the network experienced a catastrophic cascade resulting in total network collapse. Lastly, we model the economic recovery from June 2020 through March 2021 using BLS data.Item Internationalisation as an integrated process: evidence from SMEs in Lusophone Africa(Taylor & Francis, 2022-05-13) Goncalves, MarcusThis study focuses on extant internationalization theories, attempting to elucidate the entry modes adopted by Lusophone African SMEs. It offers a critical overview of the leading frameworks, focusing on their primary attributes, chal- lenges, and pitfalls in depicting similarities in the international- ization process and shortfalls in entry mode predictions. Based on the author’s challenges when investigating 29 Lusophone African SMEs in Mozambique and Angola in 2016, an inte- grated and more holistic framework for internationalization is proposed. It considers advancements in ICT and business digitalization via the internet, web-enabled tools, and platforms, including social media and online professional communities of practices.Item Conway’s Circle Theorem: a short proof, enabling generalization to polygons(2021-11-02) Braude, EricJohn Conway’s Circle Theorem is a gem of plane geometry: the six points formed by continuing the sides of a triangle beyond every vertex by the length of its opposite side, are concyclic. The theorem has attracted several proofs, even adorned Mathcamp T-shirts. We present a short proof that views the extended sides as equal tangents of the incircle, a perspective that enables generalization to polygons.Item Internationalisation as an integrated process: evidence from SMEs in Lusophone Africa(2021-10) Goncalves, MarcusItem Local response to global crisis – the effect of COVID-19 pandemic on SMEs and government export assistance programs in Central California(Informa UK Limited, 2021-10-02) Xia, Hui (Harry); Milevoj, Emil; Goncalves, MarcusThis study focuses on the effectiveness of export assistance programs (EAPs) perceived by the SMEs in Central California before and during the Covid-19 pandemic. Through the survey data and semi-structured interviews conducted with representatives from community banks and related government agencies, we find that EAPs were perceived less effective in financial support, information services, export facilitating, and education and training-related programs during the pandemic. Meanwhile, SMEs engaged in international trade more actively sought government assistance benefits, including the Paycheck Protection Program and Economic Injury Disaster Loan during the pandemic, besides EAPs such as Export Credit Insurance.Item How to facilitate productive project planning meetings: a practical guide to ensuring project success(Maven House, 2018) Maltzman, Richard (Rich); Stewart, JimRigorous planning is vital to your project execution and success. Projects are often multifunctional, requiring input from various stakeholders. Project planning often tends to be done piecemeal or not at all, often leading to missing and/or incomplete information and correspondingly poor results. This book will show you how to do it right. How to Facilitate Productive Project Planning Meetings is a guide to help you plan your projects by showing you how to effectively facilitate productive face-to-face kickoff sessions (both in person and virtual) and ongoing planning meetings. Effective planning meetings will help you not only develop key artifacts but also provide continuous team building. You’ll also learn about the impacts of culture (organizational and global) on team dynamics and discover methods to ameliorate these impacts. A case study of building a sustainable house will help you understand the concepts and grasp the terminology. The book will also feature dozens of illustrative stories (from the authors as well as other practicing project managers) that will illustrate meeting techniques that went well (or not so well). Numerous templates, sample schedules, and checklists round out the value of this book in helping you facilitate effective meetings.