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  1. Book ; Online: Open Problems and Modern Solutions for Deep Reinforcement Learning

    Chen, Weiqin

    2023  

    Abstract: Deep Reinforcement Learning (DRL) has achieved great success in solving complicated decision-making problems. Despite the successes, DRL is frequently criticized for many reasons, e.g., data inefficient, inflexible and intractable reward design. In this ... ...

    Abstract Deep Reinforcement Learning (DRL) has achieved great success in solving complicated decision-making problems. Despite the successes, DRL is frequently criticized for many reasons, e.g., data inefficient, inflexible and intractable reward design. In this paper, we review two publications that investigate the mentioned issues of DRL and propose effective solutions. One designs the reward for human-robot collaboration by combining the manually designed extrinsic reward with a parameterized intrinsic reward function via the deterministic policy gradient, which improves the task performance and guarantees a stronger obstacle avoidance. The other one applies selective attention and particle filters to rapidly and flexibly attend to and select crucial pre-learned features for DRL using approximate inference instead of backpropagation, thereby improving the efficiency and flexibility of DRL. Potential avenues for future work in both domains are discussed in this paper.
    Keywords Computer Science - Machine Learning
    Subject code 629
    Publishing date 2023-02-04
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: Exploring AI Literacy Among Older Adults.

    Kaur, Amrat / Chen, Weiqin

    Studies in health technology and informatics

    2023  Volume 306, Page(s) 9–16

    Abstract: Artificial Intelligence (AI) technology is increasingly being integrated into our daily lives and many aspects of society. AI is viewed as a new opportunity to promote independent living and well-being for older adults. AI literacy plays an important ... ...

    Abstract Artificial Intelligence (AI) technology is increasingly being integrated into our daily lives and many aspects of society. AI is viewed as a new opportunity to promote independent living and well-being for older adults. AI literacy plays an important role in older adults' acceptance and use of AI-enabled products and services. However, to our knowledge, no research has investigated AI literacy among older adults. The study aims to address this gap by collecting and analysing data on older adults' knowledge and understanding of AI and their experiences and concerns regarding AI-enabled products and services. In total, 207 older adults, aged 60 years and over, participated in the study, including 182 who answered a survey and 25 who participated in semi-structured interviews. The results show a variety levels of AI literacy among the participants. Many are interested in learning more about AI so they can make informed decisions about AI-enabled products and services. This study has not only produced insights into AI literacy among older adults but also contributed to increasing the awareness of AI among the participants and has provided recommendations on measures to enhance older adults' AI competencies.
    MeSH term(s) Humans ; Middle Aged ; Aged ; Artificial Intelligence ; Literacy ; Independent Living ; Knowledge ; Learning
    Language English
    Publishing date 2023-08-25
    Publishing country Netherlands
    Document type Journal Article
    ISSN 1879-8365
    ISSN (online) 1879-8365
    DOI 10.3233/SHTI230589
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Comparative transcriptome analysis explored the molecular mechanisms of a luxR-type regulator regulating intracellular survival of Aeromonas hydrophila.

    Chen, Weiqin / Mao, Leilei / Yan, Qingpi / Zhao, Lingmin / Huang, Lixing / Zhang, Jiaonan / Qin, Yingxue

    Journal of fish diseases

    2024  , Page(s) e13949

    Abstract: Aeromonas hydrophila is not a traditional intracellular bacterium. However, previous studies revealed that pathogenic A. hydrophila B11 could temporarily survive for at least 24 h in fish phagocytes, and the regulation of intracellular survival in ... ...

    Abstract Aeromonas hydrophila is not a traditional intracellular bacterium. However, previous studies revealed that pathogenic A. hydrophila B11 could temporarily survive for at least 24 h in fish phagocytes, and the regulation of intracellular survival in bacteria was associated with regulators of the LuxR-type. The mechanisms of luxR
    Language English
    Publishing date 2024-03-31
    Publishing country England
    Document type Journal Article
    ZDB-ID 432109-1
    ISSN 1365-2761 ; 0140-7775
    ISSN (online) 1365-2761
    ISSN 0140-7775
    DOI 10.1111/jfd.13949
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: What do faculty members know about universal design and digital accessibility? A qualitative study in computer science and engineering disciplines.

    Sanderson, Norun Christine / Kessel, Siri / Chen, Weiqin

    Universal access in the information society

    2022  Volume 21, Issue 2, Page(s) 351–365

    Abstract: ... ...

    Abstract Purpose
    Language English
    Publishing date 2022-03-29
    Document type Journal Article
    ISSN 1615-5297
    ISSN (online) 1615-5297
    DOI 10.1007/s10209-022-00875-x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Book ; Online: Probabilistic Constraint for Safety-Critical Reinforcement Learning

    Chen, Weiqin / Subramanian, Dharmashankar / Paternain, Santiago

    2023  

    Abstract: In this paper, we consider the problem of learning safe policies for probabilistic-constrained reinforcement learning (RL). Specifically, a safe policy or controller is one that, with high probability, maintains the trajectory of the agent in a given ... ...

    Abstract In this paper, we consider the problem of learning safe policies for probabilistic-constrained reinforcement learning (RL). Specifically, a safe policy or controller is one that, with high probability, maintains the trajectory of the agent in a given safe set. We establish a connection between this probabilistic-constrained setting and the cumulative-constrained formulation that is frequently explored in the existing literature. We provide theoretical bounds elucidating that the probabilistic-constrained setting offers a better trade-off in terms of optimality and safety (constraint satisfaction). The challenge encountered when dealing with the probabilistic constraints, as explored in this work, arises from the absence of explicit expressions for their gradients. Our prior work provides such an explicit gradient expression for probabilistic constraints which we term Safe Policy Gradient-REINFORCE (SPG-REINFORCE). In this work, we provide an improved gradient SPG-Actor-Critic that leads to a lower variance than SPG-REINFORCE, which is substantiated by our theoretical results. A noteworthy aspect of both SPGs is their inherent algorithm independence, rendering them versatile for application across a range of policy-based algorithms. Furthermore, we propose a Safe Primal-Dual algorithm that can leverage both SPGs to learn safe policies. It is subsequently followed by theoretical analyses that encompass the convergence of the algorithm, as well as the near-optimality and feasibility on average. In addition, we test the proposed approaches by a series of empirical experiments. These experiments aim to examine and analyze the inherent trade-offs between the optimality and safety, and serve to substantiate the efficacy of two SPGs, as well as our theoretical contributions.

    Comment: arXiv admin note: text overlap with arXiv:2210.00596
    Keywords Computer Science - Machine Learning ; Computer Science - Artificial Intelligence
    Subject code 006
    Publishing date 2023-06-29
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article ; Online: A hybrid level set model for image segmentation.

    Chen, Weiqin / Liu, Changjiang / Basu, Anup / Pan, Bin

    PloS one

    2021  Volume 16, Issue 6, Page(s) e0251914

    Abstract: Active contour models driven by local binary fitting energy can segment images with inhomogeneous intensity, while being prone to falling into a local minima. However, the segmentation result largely depends on the location of the initial contour. We ... ...

    Abstract Active contour models driven by local binary fitting energy can segment images with inhomogeneous intensity, while being prone to falling into a local minima. However, the segmentation result largely depends on the location of the initial contour. We propose an active contour model with global and local image information. The local information of the model is obtained by bilateral filters, which can also enhance the edge information while smoothing the image. The local fitting centers are calculated before the contour evolution, which can alleviate the iterative process and achieve fast image segmentation. The global information of the model is obtained by simplifying the C-V model, which can assist contour evolution, thereby increasing accuracy. Experimental results show that our algorithm is insensitive to the initial contour position, and has higher precision and speed.
    MeSH term(s) Algorithms ; Computer Simulation ; Image Interpretation, Computer-Assisted/methods ; Image Processing, Computer-Assisted/methods ; Models, Statistical ; Pattern Recognition, Automated/methods
    Language English
    Publishing date 2021-06-07
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 1932-6203
    ISSN (online) 1932-6203
    DOI 10.1371/journal.pone.0251914
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Neddylation Regulates Class IIa and III Histone Deacetylases to Mediate Myoblast Differentiation.

    Zhou, Hongyi / Su, Huabo / Chen, Weiqin

    International journal of molecular sciences

    2021  Volume 22, Issue 17

    Abstract: As the largest tissue in the body, skeletal muscle has multiple functions in movement and energy metabolism. Skeletal myogenesis is controlled by a transcriptional cascade including a set of muscle regulatory factors (MRFs) that includes Myogenic ... ...

    Abstract As the largest tissue in the body, skeletal muscle has multiple functions in movement and energy metabolism. Skeletal myogenesis is controlled by a transcriptional cascade including a set of muscle regulatory factors (MRFs) that includes Myogenic Differentiation 1 (MYOD1), Myocyte Enhancer Factor 2 (MEF2), and Myogenin (MYOG), which direct the fusion of myogenic myoblasts into multinucleated myotubes. Neddylation is a posttranslational modification that covalently conjugates ubiquitin-like NEDD8 (neural precursor cell expressed, developmentally downregulated 8) to protein targets. Inhibition of neddylation impairs muscle differentiation; however, the underlying molecular mechanisms remain less explored. Here, we report that neddylation is temporally regulated during myoblast differentiation. Inhibition of neddylation through pharmacological blockade using MLN4924 (Pevonedistat) or genetic deletion of NEDD8 Activating Enzyme E1 Subunit 1 (NAE1), a subunit of the E1 neddylation-activating enzyme, blocks terminal myoblast differentiation partially through repressing MYOG expression. Mechanistically, we found that neddylation deficiency enhances the mRNA and protein expressions of class IIa histone deacetylases 4 and 5 (HDAC4 and 5) and prevents the downregulation and nuclear export of class III HDAC (NAD-Dependent Protein Deacetylase Sirtuin-1, SIRT1), all of which have been shown to repress MYOD1-mediated MYOG transcriptional activation. Together, our findings for the first time identify the crucial role of neddylation in mediating class IIa and III HDAC co-repressors to control myogenic program and provide new insights into the mechanisms of muscle disease and regeneration.
    MeSH term(s) Cell Differentiation ; Cell Line ; Histone Deacetylases/genetics ; Histone Deacetylases/metabolism ; Humans ; MyoD Protein/genetics ; MyoD Protein/metabolism ; Myoblasts, Skeletal/metabolism ; Myogenin/genetics ; Myogenin/metabolism ; NEDD8 Protein/genetics ; NEDD8 Protein/metabolism ; Protein Processing, Post-Translational ; Repressor Proteins/genetics ; Repressor Proteins/metabolism ; Sirtuin 1/genetics ; Sirtuin 1/metabolism ; Ubiquitin-Activating Enzymes/genetics ; Ubiquitin-Activating Enzymes/metabolism
    Chemical Substances MYOG protein, human ; MyoD Protein ; MyoD1 myogenic differentiation protein ; Myogenin ; NEDD8 Protein ; NEDD8 protein, human ; Repressor Proteins ; SIRT1 protein, human (EC 3.5.1.-) ; Sirtuin 1 (EC 3.5.1.-) ; HDAC4 protein, human (EC 3.5.1.98) ; HDAC5 protein, human (EC 3.5.1.98) ; Histone Deacetylases (EC 3.5.1.98) ; Ubiquitin-Activating Enzymes (EC 6.2.1.45) ; NAE protein, human (EC 6.3.2.-)
    Language English
    Publishing date 2021-09-01
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2019364-6
    ISSN 1422-0067 ; 1422-0067 ; 1661-6596
    ISSN (online) 1422-0067
    ISSN 1422-0067 ; 1661-6596
    DOI 10.3390/ijms22179509
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: AGPAT3 Deficiency Impairs Adipocyte Differentiation and Leads to a Lean Phenotype in Mice.

    Zhou, Hongyi / Fick, Kendra / Patel, Vijay / Hilton, Lisa Renee / Kim, Ha Won / Bagi, Zsolt / Weintraub, Neal L / Chen, Weiqin

    American journal of physiology. Endocrinology and metabolism

    2024  

    Abstract: Acylglycerophosphate acyltransferases (AGPATs) catalyze the de novo formation of phosphatidic acid to synthesize glycerophospholipids and triglycerides. AGPATs demonstrate unique physiological roles despite a similar biochemical function. AGPAT3 is ... ...

    Abstract Acylglycerophosphate acyltransferases (AGPATs) catalyze the de novo formation of phosphatidic acid to synthesize glycerophospholipids and triglycerides. AGPATs demonstrate unique physiological roles despite a similar biochemical function. AGPAT3 is highly expressed in the testis, kidney, and liver, with intermediate expression in adipose tissue. Loss of Agpat3 is associated with reproductive abnormalities and visual dysfunction. However, the role of AGPAT3 in adipose tissue and whole-body metabolism has not been investigated. We found that male
    Language English
    Publishing date 2024-05-08
    Publishing country United States
    Document type Journal Article
    ZDB-ID 603841-4
    ISSN 1522-1555 ; 0193-1849
    ISSN (online) 1522-1555
    ISSN 0193-1849
    DOI 10.1152/ajpendo.00012.2024
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Book ; Online: Policy Gradients for Probabilistic Constrained Reinforcement Learning

    Chen, Weiqin / Subramanian, Dharmashankar / Paternain, Santiago

    2022  

    Abstract: This paper considers the problem of learning safe policies in the context of reinforcement learning (RL). In particular, we consider the notion of probabilistic safety. This is, we aim to design policies that maintain the state of the system in a safe ... ...

    Abstract This paper considers the problem of learning safe policies in the context of reinforcement learning (RL). In particular, we consider the notion of probabilistic safety. This is, we aim to design policies that maintain the state of the system in a safe set with high probability. This notion differs from cumulative constraints often considered in the literature. The challenge of working with probabilistic safety is the lack of expressions for their gradients. Indeed, policy optimization algorithms rely on gradients of the objective function and the constraints. To the best of our knowledge, this work is the first one providing such explicit gradient expressions for probabilistic constraints. It is worth noting that the gradient of this family of constraints can be applied to various policy-based algorithms. We demonstrate empirically that it is possible to handle probabilistic constraints in a continuous navigation problem.
    Keywords Computer Science - Machine Learning
    Subject code 006
    Publishing date 2022-10-02
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  10. Article ; Online: Integrating Universal Design and Accessibility into Computer Science Curricula - A Review of Literature and Practices in Europe.

    Nishchyk, Anna / Chen, Weiqin

    Studies in health technology and informatics

    2018  Volume 256, Page(s) 56–66

    Abstract: The absence of accessibility in many ICT systems and products indicates insufficient accessibility competence among designers, developers and project managers. Higher education institutions play an important role in raising awareness and competence and ... ...

    Abstract The absence of accessibility in many ICT systems and products indicates insufficient accessibility competence among designers, developers and project managers. Higher education institutions play an important role in raising awareness and competence and in preparing universal design and digital accessibility specialists. Although many universities are teaching accessibility as part of the biomedical, special education and disability studies programmes, few provide accessibility education in technical specialisations such as computer science. By combining literature review and manual search and inspection we aim at investigating the state of the art in integrating universal design and digital accessibility into the curricula of computer sciences-related programmes.
    MeSH term(s) Curriculum ; Disabled Persons ; Equipment Design ; Europe ; Humans ; Research ; Universities ; User-Computer Interface
    Language English
    Publishing date 2018-10-29
    Publishing country Netherlands
    Document type Journal Article ; Review
    ISSN 1879-8365
    ISSN (online) 1879-8365
    Database MEDical Literature Analysis and Retrieval System OnLINE

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