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  1. Article ; Online: Electrostatic interactions between rough dielectric particles.

    Gorman, Matthew / Ruan, Xuan / Ni, Rui

    Physical review. E

    2024  Volume 109, Issue 3-1, Page(s) 34902

    Abstract: From colloid suspension to particle aggregation in protoplanetary formation, electrostatic attraction and repulsion between particles is a key mechanism behind the aggregation and clustering of particles. Although most studies have focused on canonical ... ...

    Abstract From colloid suspension to particle aggregation in protoplanetary formation, electrostatic attraction and repulsion between particles is a key mechanism behind the aggregation and clustering of particles. Although most studies have focused on canonical spherical particles, it remains unclear how nonspherical and rough dielectric particles interact and whether the complicated interplay between roughness and charge distribution affects their force couplings. Here a boundary-element method model was leveraged to study electrostatic interactions between charged dielectric particles with modular, axisymmetric surface features. Charge accumulation at convex surface asperities decreases the strength of electrostatic interactions between particles, and the sensitivity of the electrostatic force to the particle surface roughness and orientation is especially apparent at small particle separations. Surface interactions between the particle near-contact regions were isolated to determine the degree that near-contact interactions dictate the relationship between the net electrostatic force and the particle roughness and orientation. A correction factor ΔF is introduced to recover higher order dielectric effects from a low order analytical model. Finally, implications of surface charge asymmetries produced for different particle orientations and surface roughnesses on the long-standing problem of triboelectrification are discussed.
    Language English
    Publishing date 2024-04-18
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2844562-4
    ISSN 2470-0053 ; 2470-0045
    ISSN (online) 2470-0053
    ISSN 2470-0045
    DOI 10.1103/PhysRevE.109.034902
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Universality and Intermittency of Pair Dispersion in Turbulence.

    Tan, Shiyong / Ni, Rui

    Physical review letters

    2022  Volume 128, Issue 11, Page(s) 114502

    Abstract: Turbulence can disperse a concentrated parcel of pollutants at a rate over nine orders of magnitude higher than its purely diffusive counterpart. One intriguing signature of turbulent dispersion is its superdiffusive scaling. However, the universality of ...

    Abstract Turbulence can disperse a concentrated parcel of pollutants at a rate over nine orders of magnitude higher than its purely diffusive counterpart. One intriguing signature of turbulent dispersion is its superdiffusive scaling. However, the universality of this scaling law is still in question. By leveraging a new laboratory facility, particle pairs with small initial separations can be tracked over four decades of separation in time and five decades of separation in squared displacement, thereby observing the full range of dispersion scaling laws. The results show that the classical Richardson cubic scaling will be reached not for an initial separation asymptotically close to zero but at a critical value, and this value does not appear to depend on the Reynolds number, providing an effective way to study universal dispersion dynamics. Additionally, the results agree well with the prediction based on the multifractal model and may help reconcile different reported scaling laws from laboratory experiments and field studies.
    Language English
    Publishing date 2022-04-01
    Publishing country United States
    Document type Journal Article
    ZDB-ID 208853-8
    ISSN 1079-7114 ; 0031-9007
    ISSN (online) 1079-7114
    ISSN 0031-9007
    DOI 10.1103/PhysRevLett.128.114502
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Tan and Ni Reply.

    Tan, Shiyong / Ni, Rui

    Physical review letters

    2022  Volume 130, Issue 2, Page(s) 29402

    Language English
    Publishing date 2022-04-01
    Publishing country United States
    Document type Journal Article
    ZDB-ID 208853-8
    ISSN 1079-7114 ; 0031-9007
    ISSN (online) 1079-7114
    ISSN 0031-9007
    DOI 10.1103/PhysRevLett.130.029402
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Tmed10 deficiency results in impaired exocrine pancreatic differentiation in zebrafish larvae.

    Tao, Zewen / Yang, Di / Ni, Rui

    Developmental biology

    2023  Volume 503, Page(s) 43–52

    Abstract: Transmembrane p24 trafficking protein 10 (TMED10) is a conserved vesicle trafficking protein. It is dysregulated in Alzheimer disease and plays a pivotal role in the pathogenesis of Alzheimer disease. In addition to the brain, TMED10 is highly expressed ... ...

    Abstract Transmembrane p24 trafficking protein 10 (TMED10) is a conserved vesicle trafficking protein. It is dysregulated in Alzheimer disease and plays a pivotal role in the pathogenesis of Alzheimer disease. In addition to the brain, TMED10 is highly expressed in the exocrine pancreas; however, its biological functions and underlying mechanisms remain largely unknown. We studied reduced Tmed10 in zebrafish embryos by morpholino oligonucleotide knockdown and CRISPR-Cas9 mutagenesis. Tmed10-deficient embryos showed extensive loss of acinar mass and impaired acinar differentiation. TMED10 has been reported to have an inhibitory effect on γ-secretase. As one of the substrates of γ-secretase, membrane-bound β-catenin was significantly reduced in Tmed10-deficient embryos. Increased γ-secretase activity in wild-type embryos resulted in a phenotype similar to that of tmed10 mutants. And the mutant phenotype could be rescued by treatment with the γ-secretase inhibitor, N-[N-(3, 5-difluorophenacetyl)-l-alanyl]-s-phenylglycinet-butyl ester (DAPT). In addition, the reduced membrane-bound β-catenin was accompanied with up-regulated β-catenin target genes in Tmed10-deficient embryos. Overexpression of β-catenin signaling inhibitor Dickkopf-1 (DKK-1) could rescue the exocrine pancreas defects. Taken together, our study reveals that Tmed10 regulates exocrine pancreatic differentiation through γ-secretase. Reduced membrane-bound β-catenin, accompanied with hyperactivation of β-catenin signaling, is an important cause of exocrine pancreas defects in Tmed10-deficient embryos. Our study reaffirms the importance of appropriate β-catenin signaling in exocrine pancreas development. These findings may provide a theoretical basis for the development of treatment strategies for TMED10-related diseases.
    MeSH term(s) Animals ; Alzheimer Disease ; Amyloid Precursor Protein Secretases/genetics ; beta Catenin/genetics ; Larva ; Pancreas, Exocrine/embryology ; Pancreas, Exocrine/metabolism ; Zebrafish/genetics ; Nucleocytoplasmic Transport Proteins/metabolism
    Chemical Substances Amyloid Precursor Protein Secretases (EC 3.4.-) ; beta Catenin ; Nucleocytoplasmic Transport Proteins
    Language English
    Publishing date 2023-08-17
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1114-9
    ISSN 1095-564X ; 0012-1606
    ISSN (online) 1095-564X
    ISSN 0012-1606
    DOI 10.1016/j.ydbio.2023.08.003
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Eradicating the tumor "seeds": nanomedicines-based therapies against cancer stem cells.

    Li, Lin / Ni, Rui / Zheng, Dan / Chen, Lin

    Daru : journal of Faculty of Pharmacy, Tehran University of Medical Sciences

    2023  Volume 31, Issue 1, Page(s) 83–94

    Abstract: Objectives: Cancer stem cells (CSCs), a small subpopulation of cells with high tumorigenesis and strong intrinsic drug resistance, exhibit self-renewal and differentiation abilities. CSCs play a crucial role in tumor progression, drug resistance, ... ...

    Abstract Objectives: Cancer stem cells (CSCs), a small subpopulation of cells with high tumorigenesis and strong intrinsic drug resistance, exhibit self-renewal and differentiation abilities. CSCs play a crucial role in tumor progression, drug resistance, recurrence and metastasis,and conventional therapy is not enough to eradicate them. Therefore, developing novel therapies targeting CSCs to increase drug sensitivity and preventing relapse is essential. The objective of this review is to present nanotherapies that target and eradicate the tumor "seeds".
    Evidence acquisition: Evidence was collected and sorted from the literature ranging from 2000 to 2022, using appropriate keywords and key phrases as search terms within scientific databases such as Web of Science, PubMed and Google Scholar.
    Results: Nanoparticle drug delivery systems have been successfully applied to gain longer circulation time, more precise targeting capability and better stability during cancer treatment. Nanotechnology-based strategies that have been used to target CSCs, include (1) encapsulating small molecular drugs and genes by nanotechnology, (2) targeting CSC signaling pathways, (3) utilizing nanocarriers targeting for specific markers of CSCs, (4) improving photothermal/ photodynamic therapy (PTT/PDT), 5)targeting the metabolism of CSCs and 6) enhancing nanomedicine-aided immunotherapy.
    Conclusion: This review summarizes the biological hallmarks and markers of CSCs, and the nanotechnology-based therapies to kill them. Nanoparticle drug delivery systems are appropriate means for delivering drugs to tumors through enhanced permeability and retention (EPR) effect. Furthermore, surface modification with special ligands or antibodies improves the recognition and uptake of tumor cells or CSCs. It is expected that this review can offer insights into features of CSCs and the exploration of targeting nanodrug delivery systems.
    MeSH term(s) Humans ; Antineoplastic Agents/pharmacology ; Antineoplastic Agents/therapeutic use ; Nanomedicine ; Neoplasms/drug therapy ; Neoplasms/metabolism ; Immunotherapy ; Neoplastic Stem Cells/metabolism ; Neoplastic Stem Cells/pathology
    Chemical Substances Antineoplastic Agents
    Language English
    Publishing date 2023-03-27
    Publishing country Switzerland
    Document type Journal Article ; Review
    ZDB-ID 2129183-4
    ISSN 2008-2231 ; 1560-8115
    ISSN (online) 2008-2231
    ISSN 1560-8115
    DOI 10.1007/s40199-023-00456-0
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  6. Article ; Online: Tmed10 deficiency results in impaired exocrine pancreatic differentiation in zebrafish larvae

    Tao, Zewen / Yang, Di / Ni, Rui

    Developmental Biology. 2023 Nov., v. 503 p.43-52

    2023  

    Abstract: Transmembrane p24 trafficking protein 10 (TMED10) is a conserved vesicle trafficking protein. It is dysregulated in Alzheimer disease and plays a pivotal role in the pathogenesis of Alzheimer disease. In addition to the brain, TMED10 is highly expressed ... ...

    Abstract Transmembrane p24 trafficking protein 10 (TMED10) is a conserved vesicle trafficking protein. It is dysregulated in Alzheimer disease and plays a pivotal role in the pathogenesis of Alzheimer disease. In addition to the brain, TMED10 is highly expressed in the exocrine pancreas; however, its biological functions and underlying mechanisms remain largely unknown. We studied reduced Tmed10 in zebrafish embryos by morpholino oligonucleotide knockdown and CRISPR-Cas9 mutagenesis. Tmed10-deficient embryos showed extensive loss of acinar mass and impaired acinar differentiation. TMED10 has been reported to have an inhibitory effect on γ-secretase. As one of the substrates of γ-secretase, membrane-bound β-catenin was significantly reduced in Tmed10-deficient embryos. Increased γ-secretase activity in wild-type embryos resulted in a phenotype similar to that of tmed10 mutants. And the mutant phenotype could be rescued by treatment with the γ-secretase inhibitor, N-[N-(3, 5-difluorophenacetyl)-l-alanyl]-s-phenylglycinet-butyl ester (DAPT). In addition, the reduced membrane-bound β-catenin was accompanied with up-regulated β-catenin target genes in Tmed10-deficient embryos. Overexpression of β-catenin signaling inhibitor Dickkopf-1 (DKK-1) could rescue the exocrine pancreas defects. Taken together, our study reveals that Tmed10 regulates exocrine pancreatic differentiation through γ-secretase. Reduced membrane-bound β-catenin, accompanied with hyperactivation of β-catenin signaling, is an important cause of exocrine pancreas defects in Tmed10-deficient embryos. Our study reaffirms the importance of appropriate β-catenin signaling in exocrine pancreas development. These findings may provide a theoretical basis for the development of treatment strategies for TMED10-related diseases.
    Keywords Alzheimer disease ; Biological Sciences ; CRISPR-Cas systems ; Danio rerio ; brain ; mutagenesis ; mutants ; oligonucleotides ; pancreas ; pathogenesis ; phenotype ; Transmembrane p24 trafficking protein 10 ; γ-secretase ; Exocrine pancreas development ; β-catenin ; Zebrafish
    Language English
    Dates of publication 2023-11
    Size p. 43-52.
    Publishing place Elsevier Inc.
    Document type Article ; Online
    ZDB-ID 1114-9
    ISSN 1095-564X ; 0012-1606
    ISSN (online) 1095-564X
    ISSN 0012-1606
    DOI 10.1016/j.ydbio.2023.08.003
    Database NAL-Catalogue (AGRICOLA)

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  7. Article ; Online: Diagnosis of pancreatic cancer based on biological information of saliva

    NI Rui

    Journal of Clinical Hepatology, Vol 31, Iss 5, Pp 678-

    an analysis of current status

    2015  Volume 680

    Abstract: Pancreatic cancer is one of common malignant tumors in the digestive system. There is still no effective means for the early diagnosis of pancreatic cancer. As a mixture of oral gland secretion and oral mucosal transudate, saliva contains abundant ... ...

    Abstract Pancreatic cancer is one of common malignant tumors in the digestive system. There is still no effective means for the early diagnosis of pancreatic cancer. As a mixture of oral gland secretion and oral mucosal transudate, saliva contains abundant biological information including microorganisms, proteins, and nucleic acids, which will change when the disease occurs. So saliva can be used for the early diagnosis of pancreatic cancer. Through summarizing and analyzing the current studies and advantages of its application for early diagnosis, this article suggests that saliva bioinformatics holds promise for the application in the early diagnosis of pancreatic cancer.
    Keywords pancreatic neoplasms; saliva; biological markers; early diagnosis ; Medicine (General) ; R5-920 ; Medicine ; R
    Language Chinese
    Publishing date 2015-05-01T00:00:00Z
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article ; Online: Folding Dynamics and Its Intermittency in Turbulence.

    Qi, Yinghe / Meneveau, Charles / Voth, Greg A / Ni, Rui

    Physical review letters

    2023  Volume 130, Issue 15, Page(s) 154001

    Abstract: Fluid elements deform in turbulence by stretching and folding. In this Letter, by projecting the material deformation tensor onto the largest stretching direction, we depict the dynamics of folding through the evolution of the material curvature. Results ...

    Abstract Fluid elements deform in turbulence by stretching and folding. In this Letter, by projecting the material deformation tensor onto the largest stretching direction, we depict the dynamics of folding through the evolution of the material curvature. Results from direct numerical simulation (DNS) show that the curvature growth exhibits two regimes: first, a linear stage dominated by folding fluid elements through a persistent velocity Hessian that then transition to an exponential-growth stage driven by the stretching of already strongly bent fluid elements. This transition leads to strong curvature intermittency at later stages, which can be explained by a proposed curvature-evolution model. The link between velocity Hessian to folding provides a new way to understand the crucial steps in energy cascade and mixing in turbulence beyond the classical linear description of stretching dynamics.
    Language English
    Publishing date 2023-04-28
    Publishing country United States
    Document type Journal Article
    ZDB-ID 208853-8
    ISSN 1079-7114 ; 0031-9007
    ISSN (online) 1079-7114
    ISSN 0031-9007
    DOI 10.1103/PhysRevLett.130.154001
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Reconstructing the pressure field around swimming fish using a physics-informed neural network.

    Calicchia, Michael A / Mittal, Rajat / Seo, Jung-Hee / Ni, Rui

    The Journal of experimental biology

    2023  Volume 226, Issue 8

    Abstract: Fish detect predators, flow conditions, environments and each other through pressure signals. Lateral line ablation is often performed to understand the role of pressure sensing. In the present study, we propose a non-invasive method for reconstructing ... ...

    Abstract Fish detect predators, flow conditions, environments and each other through pressure signals. Lateral line ablation is often performed to understand the role of pressure sensing. In the present study, we propose a non-invasive method for reconstructing the instantaneous pressure field sensed by a fish's lateral line system from two-dimensional particle image velocimetry (PIV) measurements. The method uses a physics-informed neural network (PINN) to predict an optimized solution for the pressure field near and on the fish's body that satisfies both the Navier-Stokes equations and the constraints put forward by the PIV measurements. The method was validated using a direct numerical simulation of a swimming mackerel, Scomber scombrus, and was applied to experimental data of a turning zebrafish, Danio rerio. The results demonstrate that this method is relatively insensitive to the spatio-temporal resolution of the PIV measurements and accurately reconstructs the pressure on the fish's body.
    MeSH term(s) Animals ; Zebrafish ; Swimming ; Models, Biological ; Physics ; Neural Networks, Computer
    Language English
    Publishing date 2023-04-27
    Publishing country England
    Document type Journal Article ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 218085-6
    ISSN 1477-9145 ; 0022-0949
    ISSN (online) 1477-9145
    ISSN 0022-0949
    DOI 10.1242/jeb.244983
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Effect of target contrast and divided attention on the useful field of view.

    Plummer, John Paul / Chaparro, Alex / Ni, Rui

    Vision research

    2022  Volume 197, Page(s) 108050

    Abstract: Previous research has shown that there is a cost of dividing attention between the central and peripheral visual fields in a complex environment. However, it is not clear how stimulus factors, such as the contrast of the scene, affect the cost. The ... ...

    Abstract Previous research has shown that there is a cost of dividing attention between the central and peripheral visual fields in a complex environment. However, it is not clear how stimulus factors, such as the contrast of the scene, affect the cost. The current study reports the results of two studies that address this question. In Experiment 1, temporal thresholds of the Useful Field of View (UFOV) tests were measured as a function of contrast and retinal eccentricity. The results showed that central-focused attention thresholds increased (i.e., performance decreased) as contrast decreased. Peripheral and divided attention task performance decreased as eccentricity increased. Surprisingly, peripheral and divided attention task performance were the best for medium rather than high contrast targets. The unexpected poorer performance under the high contrast condition might possibly be explained by the crowding effect. To test this possible explanation, in Experiment 2 the peripheral stimuli were simplified to minimize the potential crowding effect on peripheral target detection. The results showed that the unexpected effect of contrast on the cost of dividing attention could be accounted for by the crowding effect. When combined, the results from the two experiments suggest that the cost of dividing attention between central and peripheral targets is more pronounced for objects at greater eccentricity under lower contrast conditions, consistent with a tunnel effect. The implications of this finding are discussed in the paper.
    MeSH term(s) Attention ; Humans ; Retina ; Visual Fields
    Language English
    Publishing date 2022-04-08
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 200427-6
    ISSN 1878-5646 ; 0042-6989
    ISSN (online) 1878-5646
    ISSN 0042-6989
    DOI 10.1016/j.visres.2022.108050
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