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  1. Article ; Online: Dimension-Free Bounds for the Union-Closed Sets Conjecture.

    Yu, Lei

    Entropy (Basel, Switzerland)

    2023  Volume 25, Issue 5

    Abstract: The union-closed sets conjecture states that, in any nonempty union-closed family F of subsets of a finite set, there exists an element contained in at least a proportion 1/2 of the sets of F. Using an information-theoretic method, Gilmer recently showed ...

    Abstract The union-closed sets conjecture states that, in any nonempty union-closed family F of subsets of a finite set, there exists an element contained in at least a proportion 1/2 of the sets of F. Using an information-theoretic method, Gilmer recently showed that there exists an element contained in at least a proportion 0.01 of the sets of such F. He conjectured that their technique can be pushed to the constant 3-52 which was subsequently confirmed by several researchers including Sawin. Furthermore, Sawin also showed that Gilmer's technique can be improved to obtain a bound better than 3-52 but this new bound was not explicitly given by Sawin. This paper further improves Gilmer's technique to derive new bounds in the optimization form for the union-closed sets conjecture. These bounds include Sawin's improvement as a special case. By providing cardinality bounds on auxiliary random variables, we make Sawin's improvement computable and then evaluate it numerically, which yields a bound approximately 0.38234, slightly better than 3-52≈0.38197.
    Language English
    Publishing date 2023-05-08
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2014734-X
    ISSN 1099-4300 ; 1099-4300
    ISSN (online) 1099-4300
    ISSN 1099-4300
    DOI 10.3390/e25050767
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Synthesis of Indenones via Persulfate Promoted Radical Alkylation/Cyclization of Biaryl Ynones with 1,4-Dihydropyridines.

    Wang, Wanwan / Yu, Lei

    Molecules (Basel, Switzerland)

    2024  Volume 29, Issue 2

    Abstract: The oxidative radical cascade cyclization of alkynes has emerged as a versatile strategy for the efficient construction of diverse structural units and complex molecules in organic chemistry. This work reports an alkyl radical initiated 5- ...

    Abstract The oxidative radical cascade cyclization of alkynes has emerged as a versatile strategy for the efficient construction of diverse structural units and complex molecules in organic chemistry. This work reports an alkyl radical initiated 5-
    Language English
    Publishing date 2024-01-17
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 1413402-0
    ISSN 1420-3049 ; 1431-5165 ; 1420-3049
    ISSN (online) 1420-3049
    ISSN 1431-5165 ; 1420-3049
    DOI 10.3390/molecules29020458
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    In stock of ZB MED Cologne/Königswinter

    Zs.MO 81: Show issues

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  3. Article ; Online: Residents’ Sense of Place on Micro Small Public Spaces on Epidemic Perspective

    Yu Lei / Chang Jinming

    SHS Web of Conferences, Vol 163, p

    2023  Volume 04023

    Abstract: Like other historical preservation areas, the Fayuansi Community in Beijing’s old city zone faces many problems such as high population density and a shortage of public spaces. As a community that has lasted for more than a thousand years, its block ... ...

    Abstract Like other historical preservation areas, the Fayuansi Community in Beijing’s old city zone faces many problems such as high population density and a shortage of public spaces. As a community that has lasted for more than a thousand years, its block pattern embodies the early historical pattern of Beijing city. Micro Small Public Spaces (MSPS) in the community are of great significance to the physical and mental health of residents, especially during the COVID-19 epidemic. This research investigates the habit shifts of residents’ usage of these spaces and introduces the theory of “Sense of Place”, which is a concept that refers to the manner in which individuals relate or feel about the place they live, and conducts a questionnaire survey of residents in the Fayuansi community. After analyzing the residents’ needs according to the survey, this study gives suggestions on the management of MSPSs, such as increasing the supply of both spaces and facilities, strengthening management, paying more attention to senior residents’ needs, and providing more cultural events. All these measures would strengthen residents’ sense of place and develop popular support for policy.
    Keywords Social Sciences ; H
    Subject code 710
    Language English
    Publishing date 2023-01-01T00:00:00Z
    Publisher EDP Sciences
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Book ; Online: Dimension-Free Bounds for the Union-Closed Sets Conjecture

    Yu, Lei

    2022  

    Abstract: The union-closed sets conjecture states that in any nonempty union-closed family $\mathcal{F}$ of subsets of a finite set, there exists an element contained in at least a proportion $1/2$ of the sets of $\mathcal{F}$. Using the information-theoretic ... ...

    Abstract The union-closed sets conjecture states that in any nonempty union-closed family $\mathcal{F}$ of subsets of a finite set, there exists an element contained in at least a proportion $1/2$ of the sets of $\mathcal{F}$. Using the information-theoretic method, Gilmer \cite{gilmer2022constant} recently showed that there exists an element contained in at least a proportion $0.01$ of the sets of such $\mathcal{F}$. He conjectured that his technique can be pushed to the constant $\frac{3-\sqrt{5}}{2}$ which was subsequently confirmed by several researchers \cite{sawin2022improved,chase2022approximate,alweiss2022improved,pebody2022extension}. Furthermore, Sawin \cite{sawin2022improved} showed that Gilmer's technique can be improved to obtain a bound better than $\frac{3-\sqrt{5}}{2}$, but this new bound is not explicitly given by Sawin. This paper further improves Gilmer's technique to derive new bounds in the optimization form for the union-closed sets conjecture. These bounds include Sawin's improvement as a special case. By providing cardinality bounds on auxiliary random variables, we make Sawin's improvement computable, and then evaluate it numerically which yields a bound around $0.38234$, slightly better than $\frac{3-\sqrt{5}}{2}\approx0.38197$. }

    Comment: 10 pages, to appear in Entropy as an invited paper
    Keywords Mathematics - Combinatorics ; Computer Science - Information Theory
    Subject code 511
    Publishing date 2022-12-01
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  5. Book ; Online: The Entropy Method in Large Deviation Theory

    Yu, Lei

    2022  

    Abstract: This paper illustrates the power of the entropy method in addressing problems from large deviation theory. We provide and review entropy proofs for most fundamental results in large deviation theory, including Cramer's theorem, the G\"artner--Ellis ... ...

    Abstract This paper illustrates the power of the entropy method in addressing problems from large deviation theory. We provide and review entropy proofs for most fundamental results in large deviation theory, including Cramer's theorem, the G\"artner--Ellis theorem, and Sanov's theorem. Moreover, by the entropy method, we also strengthen Sanov's theorem to the strong version.

    Comment: 32 pages. For this version, more results and references are added
    Keywords Mathematics - Probability ; Computer Science - Information Theory
    Publishing date 2022-10-24
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Book ; Online: Exponents for Concentration of Measure and Isoperimetry in Product Spaces

    Yu, Lei

    2022  

    Abstract: In this paper, we provide variational formulas for the asymptotic exponents of the concentration function in the product probability space. The variational formulas for the exponents are expressed in terms of relative entropies (which are from ... ...

    Abstract In this paper, we provide variational formulas for the asymptotic exponents of the concentration function in the product probability space. The variational formulas for the exponents are expressed in terms of relative entropies (which are from information theory) and optimal transport cost functionals (which are from optimal transport theory). Moreover, in the concentration of measure regime, our variational formula is in fact a dimension-free bound on the concentration function, which is valid for any finite dimensions. Our proofs in this paper are based on information-theoretic and optimal transport techniques, and our results verify an intimate connection among information theory, optimal transport, and concentration of measure.

    Comment: 27 pages, preliminary version
    Keywords Mathematics - Probability ; Computer Science - Information Theory ; Mathematics - Functional Analysis ; Mathematics - Metric Geometry
    Publishing date 2022-05-16
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  7. Book ; Online: Gray--Wyner and Mutual Information Regions for Doubly Symmetric Binary Sources and Gaussian Sources

    Yu, Lei

    2022  

    Abstract: Nonconvex optimization plays a key role in multi-user information theory and related fields, but it is usually difficult to solve. The rate region of the Gray--Wyner source coding system (or almost equivalently, the mutual information region) is a ... ...

    Abstract Nonconvex optimization plays a key role in multi-user information theory and related fields, but it is usually difficult to solve. The rate region of the Gray--Wyner source coding system (or almost equivalently, the mutual information region) is a typical example in nonconvex optimization, whose single-letter expression was given by Gray and Wyner. However, due to the nonconvexity of the optimization involved in this expression, previously, there was none nontrivial discrete source for which the analytic expression is known. In this paper, we propose a new strategy to solve nonconvex optimization problems. By this strategy, we provide the analytic expression for the doubly symmetric binary source (DSBS), which confirms positively a conjecture of Gray and Wyner in 1974. We also provide the analytic expression of the mutual information region for the Gaussian source, and provide (or recover) the analytic expressions of the lossy Gray--Wyner region for both the DSBS and Gaussian source. Our proof strategy relies on an auxiliary measure technique and the analytical expression of the optimal-transport divergence region.

    Comment: 18 pages. To appear in the IEEE Transactions on Information Theory
    Keywords Computer Science - Information Theory
    Subject code 003
    Publishing date 2022-12-30
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Thesis ; Online: Multi-level genetic variation and somatic genetic drift in the model seagrass species, eelgrass (Zostera marina L.)

    Yu, Lei

    2022  

    Abstract: Clonal species, such as seagrass Zostera marina, have two levels of “population”, an asexual population of ramets belonging to a single clone/genet, which is nested into the population of clones/genets, the “classical”, sexually reproducing population. ... ...

    Abstract Clonal species, such as seagrass Zostera marina, have two levels of “population”, an asexual population of ramets belonging to a single clone/genet, which is nested into the population of clones/genets, the “classical”, sexually reproducing population. Although earlier theoretical and conceptual work has repeatedly suggested that somatically generated variation plays an important role in modular species, population genetics of such species has been focused on the “classical” germline genetic variation. This thesis extends the knowledge on the multi-level genetic variation in the model seagrass species Z. marina using whole-genome resequencing. In Chapter 1, I studied the somatic genetic variation (SoGV) in a Z. marina meadow tracing back to one single sexual event. In chapter 2, I studied population genomics of Z. marina, based on the worldwide distribution of the “classical” germline genetic variation. In chapter 3, I proposed the concept of identity by heterozygosity (IBH), meaning that two diploid genomes are identically heterozygous at some genetic markers such as SNPs (single-nucleotide polymorphisms). This was used to detect ramets of the same clone/genet. In summary, two levels of SoGV, namely among cell populations, and among ramets/modules, are nested within “classical” germline genetic variation in clonal species, owing to somatic mutation and somatic genetic drift. This thesis opens up new avenues of studying multi-level genetic variation by using clonal species as model. Further modeling and theoretical work based on clonal species will broaden the current population genetics theory.
    Subject code 590
    Language English
    Publishing date 2022-05-05
    Publishing country de
    Document type Thesis ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article ; Online: The Current Situation and Development Prospect of Whole-Genome Screening

    Caiting Yang / Yu Lei / Tinglin Ren / Mingze Yao

    International Journal of Molecular Sciences, Vol 25, Iss 1, p

    2024  Volume 658

    Abstract: High-throughput genetic screening is useful for discovering critical genes or gene sequences that trigger specific cell functions and/or phenotypes. Loss-of-function genetic screening is mainly achieved through RNA interference (RNAi), CRISPR knock-out ( ... ...

    Abstract High-throughput genetic screening is useful for discovering critical genes or gene sequences that trigger specific cell functions and/or phenotypes. Loss-of-function genetic screening is mainly achieved through RNA interference (RNAi), CRISPR knock-out (CRISPRko), and CRISPR interference (CRISPRi) technologies. Gain-of-function genetic screening mainly depends on the overexpression of a cDNA library and CRISPR activation (CRISPRa). Base editing can perform both gain- and loss-of-function genetic screening. This review discusses genetic screening techniques based on Cas9 nuclease, including Cas9-mediated genome knock-out and dCas9-based gene activation and interference. We compare these methods with previous genetic screening techniques based on RNAi and cDNA library overexpression and propose future prospects and applications for CRISPR screening.
    Keywords genome screening ; CRISPR screen ; RNAi ; cDNA ; Biology (General) ; QH301-705.5 ; Chemistry ; QD1-999
    Language English
    Publishing date 2024-01-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  10. Article ; Online: Profiling Single-Cell Genome and Transcriptome by scONE-Seq.

    Yu, Lei / Wu, Angela Ruohao

    Methods in molecular biology (Clifton, N.J.)

    2023  Volume 2689, Page(s) 191–209

    Abstract: Single-cell multi-omics technologies can provide a unique perspective on tumor cellular heterogeneity. We have developed a versatile method for simultaneous transcriptome and genome profiling of single cells or single nuclei in one tube reaction, named ... ...

    Abstract Single-cell multi-omics technologies can provide a unique perspective on tumor cellular heterogeneity. We have developed a versatile method for simultaneous transcriptome and genome profiling of single cells or single nuclei in one tube reaction, named scONE-seq. It is conveniently compatible with frozen tissue from biobanks, which are a major source of patient samples for research. Here, we describe the detailed procedures to profile single-cell/nucleus transcriptome and genome. The sequencing library is compatible with both Illumina and MGI sequencers; it is also compatible with frozen tissue from biobanks, which are a major source of patient samples for research and drug discovery.
    MeSH term(s) Humans ; Transcriptome ; Cell Nucleus ; Drug Discovery ; Food ; Multiomics
    Language English
    Publishing date 2023-07-10
    Publishing country United States
    Document type Journal Article
    ISSN 1940-6029
    ISSN (online) 1940-6029
    DOI 10.1007/978-1-0716-3323-6_15
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