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  1. Article ; Online: Predicting cell types with supervised contrastive learning on cells and their types

    Yusri Dwi Heryanto / Yao-zhong Zhang / Seiya Imoto

    Scientific Reports, Vol 14, Iss 1, Pp 1-

    2024  Volume 16

    Abstract: Abstract Single-cell RNA-sequencing (scRNA-seq) is a powerful technique that provides high-resolution expression profiling of individual cells. It significantly advances our understanding of cellular diversity and function. Despite its potential, the ... ...

    Abstract Abstract Single-cell RNA-sequencing (scRNA-seq) is a powerful technique that provides high-resolution expression profiling of individual cells. It significantly advances our understanding of cellular diversity and function. Despite its potential, the analysis of scRNA-seq data poses considerable challenges related to multicollinearity, data imbalance, and batch effect. One of the pivotal tasks in single-cell data analysis is cell type annotation, which classifies cells into discrete types based on their gene expression profiles. In this work, we propose a novel modeling formalism for cell type annotation with a supervised contrastive learning method, named SCLSC (Supervised Contrastive Learning for Single Cell). Different from the previous usage of contrastive learning in single cell data analysis, we employed the contrastive learning for instance-type pairs instead of instance-instance pairs. More specifically, in the cell type annotation task, the contrastive learning is applied to learn cell and cell type representation that render cells of the same type to be clustered in the new embedding space. Through this approach, the knowledge derived from annotated cells is transferred to the feature representation for scRNA-seq data. The whole training process becomes more efficient when conducting contrastive learning for cell and their types. Our experiment results demonstrate that the proposed SCLSC method consistently achieves superior accuracy in predicting cell types compared to five state-of-the-art methods. SCLSC also performs well in identifying cell types in different batch groups. The simplicity of our method allows for scalability, making it suitable for analyzing datasets with a large number of cells. In a real-world application of SCLSC to monitor the dynamics of immune cell subpopulations over time, SCLSC demonstrates a capability to discriminate cell subtypes of CD19+ B cells that were not present in the training dataset.
    Keywords Medicine ; R ; Science ; Q
    Subject code 004
    Language English
    Publishing date 2024-01-01T00:00:00Z
    Publisher Nature Portfolio
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: Examining the cooperation between extrachromosomal DNA circles

    Jiahui Zhang / Cheng-Zhong Zhang

    eLife, Vol

    2022  Volume 11

    Abstract: In a departure from previous findings, new results suggest that free-floating pieces of DNA which carry additional copies of cancer-driving genes do not tend to cluster or have increased transcription. ...

    Abstract In a departure from previous findings, new results suggest that free-floating pieces of DNA which carry additional copies of cancer-driving genes do not tend to cluster or have increased transcription.
    Keywords extrachromosomal DNA ; oncogenes ; super-resolution imaging ; transcription factors hub ; glioblastoma ; cancer ; Medicine ; R ; Science ; Q ; Biology (General) ; QH301-705.5
    Language English
    Publishing date 2022-12-01T00:00:00Z
    Publisher eLife Sciences Publications Ltd
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: mPrivacy

    Zhong Zhang / Minho Shin

    Applied Sciences, Vol 11, Iss 11629, p

    A Privacy Policy Engine and Safeguard Mechanism in Mobile Devices

    2021  Volume 11629

    Abstract: Within the scope of mobile privacy, there are many attack methods that can leak users’ private information. The communication between applications can be used to violate permissions and access private information without asking for the user’s ... ...

    Abstract Within the scope of mobile privacy, there are many attack methods that can leak users’ private information. The communication between applications can be used to violate permissions and access private information without asking for the user’s authorization. Hence, many researchers made protection mechanisms against privilege escalation. However, attackers can further utilize inference algorithms to derive new information out of available data or improve the information quality without violating privilege limits. In this work. we describe the notion of Information Escalation Attack and propose a detection and protection mechanism using Inference Graph and Policy Engine for the user to control their policy on the App’s privilege in information escalation. Our implementation results show that the proposed privacy protection service is feasible and provides good useability.
    Keywords mobile privacy ; privacy protection mechanism ; information escalation ; inference algorithm ; Technology ; T ; Engineering (General). Civil engineering (General) ; TA1-2040 ; Biology (General) ; QH301-705.5 ; Physics ; QC1-999 ; Chemistry ; QD1-999
    Subject code 005
    Language English
    Publishing date 2021-12-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Article ; Online: Practical Straits of the Forensic Examination in China

    Zhong Zhang

    Journal of Forensic Science and Medicine, Vol 2, Iss 1, Pp 33-

    2016  Volume 38

    Abstract: With the revision of the Criminal Procedural Law of the PRC and the Civil Procedural Law of the PRC in 2012, it has entered a new historical stage of litigation system and made significant progress in forensic examination system in China. However, for a ... ...

    Abstract With the revision of the Criminal Procedural Law of the PRC and the Civil Procedural Law of the PRC in 2012, it has entered a new historical stage of litigation system and made significant progress in forensic examination system in China. However, for a long time, the illegal forensic examinations have been commonly seen in forensic practice, the right to start the forensic examination process only lies with public security and judicial authorities, while the parties only have the limited right to apply for supplementary forensic examination or re-examination. To the problem of experts′ refusal to appear in court to testify, the Criminal Procedural Law and the Civil Procedural Law have further improved the expert testimony system, but the situation has not fundamentally changed. To compensate for judges′ lack of knowledge of professional issues, the expert advisor system is introduced, but there are no workable rules. Besides, judges depend too much on and accept the expert opinions blindly become a common phenomenon in the proceedings.
    Keywords Expert advisor ; expert opinion ; forensic examination ; Public aspects of medicine ; RA1-1270
    Subject code 340
    Language English
    Publishing date 2016-01-01T00:00:00Z
    Publisher Wolters Kluwer Medknow Publications
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  5. Article ; Online: Hydrothermal synthesis, structure, and catalytic properties of a (4,6)-connected framework constructed from Keggin-type polyoxometalate units and tetranuclear copper complexes

    Jia-Yu Sun / Zi-Lan Wang / Zhong Zhang / Guo-Cheng Liu / Xiu-Li Wang

    Polyoxometalates, Vol 3, Iss 1, p

    2024  Volume 9140039

    Abstract: Under hydrothermal conditions, a Keggin-type polyoxometalate-based metal–organic complex, H4{[Cu4(EDDP)2(H2O)5]1.5(SiW12O40)}∙7.5H2O (CuW-EDDP, H4EDDP = ethylene-diamine-N,N'-dipropionic acid), was synthesized by reacting Na10[A-α-SiW9O34]·18H2O and ... ...

    Abstract Under hydrothermal conditions, a Keggin-type polyoxometalate-based metal–organic complex, H4{[Cu4(EDDP)2(H2O)5]1.5(SiW12O40)}∙7.5H2O (CuW-EDDP, H4EDDP = ethylene-diamine-N,N'-dipropionic acid), was synthesized by reacting Na10[A-α-SiW9O34]·18H2O and CuCl2·2H2O in the presence of H4EDDP ligands and characterized by powder and single-crystal X-ray diffraction, infrared spectroscopy, elemental analysis, and thermogravimetry. Interestingly, CuW-EDDP exhibited a three-dimensional structure with (4,6)-connected constructed from [SiW12O40]4− units and tetranuclear Cu complexes [Cu4(EDDP)2(H2O)5]. As an effective heterogeneous catalyst, CuW-EDDP exhibited excellent performance, good reusability, and structural stability in the selective oxidation of methyl phenyl sulfide with high conversion (100%) and selectivity (98%) within 30 min. Furthermore, the catalytic activity of CuW-EDDP in the oxidation of other sulfide derivatives was investigated.
    Keywords polyoxometalates ; keggin-type ; metal–organic complex ; catalytic oxidation ; sulfides ; Inorganic chemistry ; QD146-197
    Subject code 540
    Language English
    Publishing date 2024-03-01T00:00:00Z
    Publisher Tsinghua University Press
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article ; Online: ZNF655 mediated by LINC01210/miR‐124‐3p axis promotes the progression of gastric cancer

    Wei Bo / Xu‐Guang Wang / Min Zhang / Zhong Zhang

    Kaohsiung Journal of Medical Sciences, Vol 39, Iss 3, Pp 200-

    2023  Volume 208

    Abstract: Abstract Gastric cancer (GC) is a common malignant tumor that usually originates from the epithelium of the gastric mucosa. ZNF655 was a suppressor gene of many cancers. However, the mechanism of ZNF655 in GC remains unknown. Quantitative polymerase ... ...

    Abstract Abstract Gastric cancer (GC) is a common malignant tumor that usually originates from the epithelium of the gastric mucosa. ZNF655 was a suppressor gene of many cancers. However, the mechanism of ZNF655 in GC remains unknown. Quantitative polymerase chain reaction was used to assess the expression of ZNF655, LINC01210, and miR‐124‐3p. Western blotting was used to monitor ZNF655 protein expression. MTT, clone formation, transwell, and flow cytometry were all used to investigate the functions of GC cells. The interactions between ZNF655, LINC01210, and miR‐124‐3p were confirmed using the dual‐luciferase reporter gene assay and the RIP assay. ZNF655 was highly expressed in GC cells. ZNF655 knockdown reduced GC cell viability, proliferation, migration, invasion, and induced apoptosis. The level of miR‐124‐3p was significantly reduced in GC cells. Besides, miR‐124‐3p targeted ZNF655 and inhibited its expression. MiR‐124‐3p mimics inhibited GC cell progression, but ZNF655 overexpression reversed these effects. Moreover, LINC01210 was found to be highly expressed in GC cells and to be able to sponge miR‐124‐3p. Furthermore, inhibiting miR‐124‐3p or increasing ZNF655 could counteract the effects of LINC01210 knockdown on GC cell development. Finally, ZNF655 promoted GC cell progression and was regulated by the LINC01210/miR‐124‐3p axis.
    Keywords GC ; LINC01210 ; miR‐124‐3p ; ZNF655 ; Medicine (General) ; R5-920
    Subject code 500
    Language English
    Publishing date 2023-03-01T00:00:00Z
    Publisher Wiley
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  7. Article ; Online: Bearing-Fault Diagnosis with Signal-to-RGB Image Mapping and Multichannel Multiscale Convolutional Neural Network

    Ming Xu / Jinfeng Gao / Zhong Zhang / Heshan Wang

    Entropy, Vol 24, Iss 1569, p

    2022  Volume 1569

    Abstract: Deep learning bearing-fault diagnosis has shown strong vitality in recent years. In industrial practice, the running state of bearings is monitored by collecting data from multiple sensors, for instance, the drive end, the fan end, and the base. Given ... ...

    Abstract Deep learning bearing-fault diagnosis has shown strong vitality in recent years. In industrial practice, the running state of bearings is monitored by collecting data from multiple sensors, for instance, the drive end, the fan end, and the base. Given the complexity of the operating conditions and the limited number of bearing-fault samples, obtaining complementary fault features using the traditional fault-diagnosis method, which uses statistical characteristic in time or frequency, is difficult and relies heavily on prior knowledge. In addition, intelligent bearing-fault diagnosis based on a convolutional neural network (CNN) has several deficiencies, such as single-scale fixed convolutional kernels, excessive dependence on experts’ experience, and a limited capacity for learning a small training dataset. Considering these drawbacks, a novel intelligent bearing-fault-diagnosis method based on signal-to-RGB image mapping (STRIM) and multichannel multiscale CNN (MCMS-CNN) is proposed. First, the signals from three different sensors are converted into RGB images by the STRIM method to achieve feature fusion. To extract RGB image features effectively, the proposed MCMS-CNN is established, which can automatically learn complementary and abundant features at different scales. By increasing the width and decreasing the depth of the network, the overfitting caused by the complex network for a small dataset is eliminated, and the fault classification capability is guaranteed simultaneously. The performance of the method is verified through the Case Western Reserve University’s (CWRU) bearing dataset. Compared with different DL approaches, the proposed approach can effectively realize fault diagnosis and substantially outperform other methods.
    Keywords fault diagnosis ; multichannel and multiscale convolutional neural network (MCMS-CNN) ; rotating machinery ; sensor fusion ; signal-to-RGB image mapping (STRIM) ; Science ; Q ; Astrophysics ; QB460-466 ; Physics ; QC1-999
    Subject code 006
    Language English
    Publishing date 2022-10-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article ; Online: ACS Physical Chemistry Au

    Gemma C. Solomon / Jin Zhong Zhang / Tanja Cuk

    ACS Physical Chemistry Au, Vol 2, Iss 1, Pp 1-

    One Year In

    2022  Volume 2

    Keywords Physical and theoretical chemistry ; QD450-801
    Language English
    Publishing date 2022-01-01T00:00:00Z
    Publisher American Chemical Society
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article: Hidden biodiversity revealed by DNA barcoding in black fly genus

    Ruiling, Zhang / Zhong, Zhang

    Journal of vector borne diseases

    2021  Volume 57, Issue 2, Page(s) 128–138

    Abstract: Background & objectives: The black fly genus Simulium Latreille is one of the most important medical insect group of the family Simuliidae (Diptera) and many species of this genus are important pests of human and animals, while some of them also ... ...

    Abstract Background & objectives: The black fly genus Simulium Latreille is one of the most important medical insect group of the family Simuliidae (Diptera) and many species of this genus are important pests of human and animals, while some of them also represent vectors of pathogens. Correct species identification is essential to the implementation of control measures for species of medical or agricultural importance.
    Methods: In this study, the usefulness of DNA barcoding was discussed in distinguishing species of Simulium.
    Results: Analysis showed hidden biodiversity, usually referred to in Simuliidae as cryptic species, which was detected in 15 species. Firstly, intraspecific divergences of eleven species was unexpectedly high and the maximum distances of them ranged from 5.1-16.8%. Based on the differential of K2P (Kimura 2-Parameter) distances, sequences were subdivided into two or three groups, respectively. Secondly, extremely low interspecific divergences were detected in eight groups of species, and shared haplotypes were also found among them. Furthermore, the subdivision within species and shared haplotypes among some species were all supported by the NJ (Neighbour-Joining) analysis.
    Interpretation & conclusion: Our results confirmed that DNA barcoding was a powerful tool for revealing hidden species diversity of black flies. Further work is needed to reveal ambiguous species delimitation in some problematic species groups.
    MeSH term(s) Animals ; Biodiversity ; DNA Barcoding, Taxonomic ; Haplotypes ; Humans ; Simuliidae/classification ; Simuliidae/genetics
    Language English
    Publishing date 2021-07-21
    Publishing country India
    Document type Evaluation Study ; Journal Article
    ZDB-ID 2161218-3
    ISSN 0972-9062
    ISSN 0972-9062
    DOI 10.4103/0972-9062.310862
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Leakage Current Sensor and Neural Network for MOA Monitoring

    Tao He / Yang Li / Zhong Zhang / Pengfei Shen / Yu Zhang

    Computational Intelligence and Neuroscience, Vol

    2022  Volume 2022

    Abstract: Metal-oxide arrester (MOA) has been widely used in electric power systems. The leakage current monitoring of MOA can not only detect the MOA’s running state continuously and intelligently but also reduce the unexpected outage of the equipment, which is ... ...

    Abstract Metal-oxide arrester (MOA) has been widely used in electric power systems. The leakage current monitoring of MOA can not only detect the MOA’s running state continuously and intelligently but also reduce the unexpected outage of the equipment, which is also beneficial to the stability of the grid. The MOA loses its protection function due to various faults caused by excessive leakage current in actual running. This article studies the monitoring method of MOA based on leakage current sensor and back propagation (BP) neural network. At first, we design a novel leakage current sensor to acquire the leakage current of MOA. Then, the leakage current measurement of MOA based on harmonic analysis is proposed. Finally, the strong training ability of the BP neural network is used to train some key parameters that can reflect the aging of MOA so as to monitor the MOA state. The experimental results show that the leakage current acquired from the simulation is close to the actual leakage current that needs to be measured. It is also shown that the proposed method has good anti-interference and can effectively monitor the aging of MOA. Through the training of the BP neural network, the experiments prove that the training method in this article is superior to other neural network training methods obviously.
    Keywords Computer applications to medicine. Medical informatics ; R858-859.7 ; Neurosciences. Biological psychiatry. Neuropsychiatry ; RC321-571
    Subject code 620
    Language English
    Publishing date 2022-01-01T00:00:00Z
    Publisher Hindawi Limited
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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