Achieving the Optimal Steaming Capacity and Delay Using Random Regular Digraphs in P2P Networks

In earlier work, we showed that it is possible to achieve $O(\log N)$ streaming delay with high probability in a peer-to-peer network, where each peer has as little as four neighbors, while achieving any arbitrary fraction of the maximum possible streaming rate. However, the constant in the $O(log N)$ delay term becomes rather large as we get closer to the maximum streaming rate. In this paper, we design an alternative pairing and chunk dissemination algorithm that allows us to transmit at the maximum streaming rate while ensuring that all, but a negligible fraction of the peers, receive the data stream with $O(\log N)$ delay with high probability. The result is established by examining the properties of graph formed by the union of two or more random 1-regular digraphs, i.e., directed graphs in which each node has an incoming and an outgoing node degree both equal to one

Neoliberalism and the Politics of Social Enterprises in South Korea: The Dynamics of Neoliberal Governmentality and Hegemony

Social enterprises have been promoted globally as alternative economic institutions to neoliberalism for the last few decades. In this study, I explored how social enterprises and the subjectivities of social entrepreneurs emerged as new discursive formations and institutional mechanisms in the neoliberal transformation of governance strategies in South Korea. Three broader questions guide this study. First, how have social enterprises emerged as a new discursive formation and a new institutional mechanism in neoliberal South Korean society? Second, how are the new subjectivities of social entrepreneurs produced in ways that are consistent with neoliberalism? Finally what are the implications of the emergence of social enterprises and the subjectivities of social entrepreneurs in terms of the neoliberal transformations of South Korean society? I situated these research questions within the theoretical frameworks of Neo-Marxist social theory and Foucauldian governmentality theory. In order to answer these questions, I analyzed newspaper articles, South Korean governmental policy reports, academic journal articles, and guidebooks for social entrepreneurs. I argue that the promotion of social enterprises operates as a new neoliberal government strategy that captures anti-neoliberal progressive social movements and shifts the responsibilities of the state for solving particularly problems of poverty and unemployment onto civil society and social activists. Central findings demonstrate that, despite the pervasiveness of the statements of progressive social movements—solidarity, public good, feminist empowerment, and social change—in the discourses of social enterprises, these statements are dominated by the logic and principles of the market regardless of the discourse producers’ political orientations. In forming the partnership with progressive social movement forces, state power mobilizes them into the mechanisms to promote social enterprises. Social activists are encouraged to be professional social entrepreneurs by arming themselves with an entrepreneurial spirit, knowledge of business administration, and a sense of responsibility for the disadvantaged. Theoretically, this study has broader implications in terms of its exploration of new neoliberal governance mechanisms inscribed in the promotion of social enterprises and social entrepreneurs. This study also has important practical implications insofar as it reveals how Korean progressive leftists are unintentionally allied with neoliberalism, and thereby ironically reinforce its hegemony

Alternative splicing and extra-telomeric role of telomerase reverse transcriptase isoforms in human embryonic stem cells

Human telomerase, a ribonucleoprotein complex consisting of a catalytic subunit (hTERT) and a RNA template component (TERC), prevents telomere attrition in human embryonic stem cells (hESCs) providing these cells with prolonged replicative capacity. Interestingly, hTERT has several alternatively spliced isoforms, most of which are catalytically inactive. One alternative splicing event involving a complete loss of exons 7 and 8 results in a catalytically inactive isoform called β-hTERT. The β-hTERT is highly expressed in certain cancer types and hESCs. Full-length hTERT (FL-hTERT) is known to translocate from nuclei to mitochondria when cells are exposed to either chronic (oxygen tension) or acute (hydrogen peroxide) oxidative stress. In this study, I examined the alternative splicing of endogenous hTERT transcript in hESC, intra-cellular localization of FL-hTERT and β-hTERT in hESCs, and the effect of overexpressing recombinant hTERT on hESC mitochondria. Human ESCs (HES2 line) were cultured under 2% oxygen and 3xFLAG tagged FL-hTERT and β-hTERT were induced by doxycycline prior to 100μM H2O2 treatment. My results demonstrate that overexpression of transgenic FL-hTERT resulted in a significant increase in endogenous β-hTERT transcript level. Additionally, doxycycline and H2O2 altered the splicing pattern of hTERT in favor of β-hTERT. I demonstrate that not only the full-length- but also β-hTERT can bind TERC, and that β-hTERT overexpression inhibits telomerase activity in vitro. However, I failed to observe the mitochondrial localization of recombinant FL-hTERT or β-hTERT. Lastly, my results demonstrate the pro-apoptotic role of β-hTERT and the pro-survival effect of FL-hTERT under H2O2-induced oxidative stress

The role of telomeres and telomerase reverse transcriptase isoforms in pluripotency induction and maintenance

Telomeres are linear guanine-rich DNA structures at the ends of chromosomes. The length of telomeric DNA is actively regulated by a number of mechanisms in highly proliferative cells such as germ cells, cancer cells, and pluripotent stem cells. Telomeric DNA is synthesized by way of the ribonucleoprotein called telomerase containing a reverse transcriptase (TERT) subunit and RNA component (TERC). TERT is highly conserved across species and ubiquitously present in their respective pluripotent cells. Recent studies have uncovered intricate associations between telomeres and the self-renewal and differentiation properties of pluripotent stem cells. Interestingly, the past decade\u27s work indicates that the TERT subunit also has the capacity to modulate mitochondrial function, to remodel chromatin structure, and to participate in key signaling pathways such as the Wnt/β-catenin pathway. Many of these non-canonical functions do not require TERT\u27s catalytic activity, which hints at possible functions for the extensive number of alternatively spliced TERT isoforms that are highly expressed in pluripotent stem cells. In this review, some of the established and potential routes of pluripotency induction and maintenance are highlighted from the perspectives of telomere maintenance, known TERT isoform functions and their complex regulation

NFTs to MARS: Multi-Attention Recommender System for NFTs

Recommender systems have become essential tools for enhancing user experiences across various domains. While extensive research has been conducted on recommender systems for movies, music, and e-commerce, the rapidly growing and economically significant Non-Fungible Token (NFT) market remains underexplored. The unique characteristics and increasing prominence of the NFT market highlight the importance of developing tailored recommender systems to cater to its specific needs and unlock its full potential. In this paper, we examine the distinctive characteristics of NFTs and propose the first recommender system specifically designed to address NFT market challenges. In specific, we develop a Multi-Attention Recommender System for NFTs (NFT-MARS) with three key characteristics: (1) graph attention to handle sparse user-item interactions, (2) multi-modal attention to incorporate feature preference of users, and (3) multi-task learning to consider the dual nature of NFTs as both artwork and financial assets. We demonstrate the effectiveness of NFT-MARS compared to various baseline models using the actual transaction data of NFTs collected directly from blockchain for four of the most popular NFT collections. The source code and data are available at https://anonymous.4open.science/r/RecSys2023-93ED

A Recommender System for NFT Collectibles with Item Feature

Recommender systems have been actively studied and applied in various domains to deal with information overload. Although there are numerous studies on recommender systems for movies, music, and e-commerce, comparatively less attention has been paid to the recommender system for NFTs despite the continuous growth of the NFT market. This paper presents a recommender system for NFTs that utilizes a variety of data sources, from NFT transaction records to external item features, to generate precise recommendations that cater to individual preferences. We develop a data-efficient graph-based recommender system to efficiently capture the complex relationship between each item and users and generate node(item) embeddings which incorporate both node feature information and graph structure. Furthermore, we exploit inputs beyond user-item interactions, such as image feature, text feature, and price feature. Numerical experiments verify the performance of the graph-based recommender system improves significantly after utilizing all types of item features as side information, thereby outperforming all other baselines.Comment: Presented at the AAAI 2023 Bridge on AI for Financial Services (https://sites.google.com/view/aaai-ai-fin/home

Diffusion-EDFs: Bi-equivariant Denoising Generative Modeling on SE(3) for Visual Robotic Manipulation

Diffusion generative modeling has become a promising approach for learning robotic manipulation tasks from stochastic human demonstrations. In this paper, we present Diffusion-EDFs, a novel SE(3)-equivariant diffusion-based approach for visual robotic manipulation tasks. We show that our proposed method achieves remarkable data efficiency, requiring only 5 to 10 human demonstrations for effective end-to-end training in less than an hour. Furthermore, our benchmark experiments demonstrate that our approach has superior generalizability and robustness compared to state-of-the-art methods. Lastly, we validate our methods with real hardware experiments. Project Website: https://sites.google.com/view/diffusion-edfs/homeComment: 31 pages, 13 figure

Visual discomfort with stereo displays: Effects of viewing distance and direction of vergence-accommodation conflict

ABSTRACT Prolonged use of conventional stereo displays causes viewer discomfort and fatigue because of the vergenceaccommodation conflict. We used a novel volumetric display to examine how viewing distance and the sign of the vergence-accommodation conflict affect discomfort and fatigue. In the first experiment, we presented a fixed conflict at short, medium, and long viewing distances. We compared subjects' symptoms in that condition and one in which there was no conflict. We observed more discomfort and fatigue with a given vergence-accommodation conflict at the longer distances. The second experiment compared symptoms when the conflict had one sign compared to when it had the opposite sign at short, medium, and long distances. We observed greater symptoms with uncrossed disparities at long distances and with crossed disparities at short distances. These findings help define comfortable viewing conditions for stereo displays