392 research outputs found

    BioModels Database: An enhanced, curated and annotated resource for published quantitative kinetic models

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    Background: Quantitative models of biochemical and cellular systems are used to answer a variety of questions in the biological sciences. The number of published quantitative models is growing steadily thanks to increasing interest in the use of models as well as the development of improved software systems and the availability of better, cheaper computer hardware. To maximise the benefits of this growing body of models, the field needs centralised model repositories that will encourage, facilitate and promote model dissemination and reuse. Ideally, the models stored in these repositories should be extensively tested and encoded in community-supported and standardised formats. In addition, the models and their components should be cross-referenced with other resources in order to allow their unambiguous identification. Description: BioModels Database http://www.ebi.ac.uk/biomodels/ is aimed at addressing exactly these needs. It is a freely-accessible online resource for storing, viewing, retrieving, and analysing published, peer-reviewed quantitative models of biochemical and cellular systems. The structure and behaviour of each simulation model distributed by BioModels Database are thoroughly checked; in addition, model elements are annotated with terms from controlled vocabularies as well as linked to relevant data resources. Models can be examined online or downloaded in various formats. Reaction network diagrams generated from the models are also available in several formats. BioModels Database also provides features such as online simulation and the extraction of components from large scale models into smaller submodels. Finally, the system provides a range of web services that external software systems can use to access up-to-date data from the database. Conclusions: BioModels Database has become a recognised reference resource for systems biology. It is being used by the community in a variety of ways; for example, it is used to benchmark different simulation systems, and to study the clustering of models based upon their annotations. Model deposition to the database today is advised by several publishers of scientific journals. The models in BioModels Database are freely distributed and reusable; the underlying software infrastructure is also available from SourceForge https://sourceforge.net/projects/biomodels/ under the GNU General Public License

    Tissue Determinants of Human NK Cell Development, Function, and Residence.

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    Immune responses in diverse tissue sites are critical for protective immunity and homeostasis. Here, we investigate how tissue localization regulates the development and function of human natural killer (NK) cells, innate lymphocytes important for anti-viral and tumor immunity. Integrating high-dimensional analysis of NK cells from blood, lymphoid organs, and mucosal tissue sites from 60 individuals, we identify tissue-specific patterns of NK cell subset distribution, maturation, and function maintained across age and between individuals. Mature and terminally differentiated NK cells with enhanced effector function predominate in blood, bone marrow, spleen, and lungs and exhibit shared transcriptional programs across sites. By contrast, precursor and immature NK cells with reduced effector capacity populate lymph nodes and intestines and exhibit tissue-resident signatures and site-specific adaptations. Together, our results reveal anatomic control of NK cell development and maintenance as tissue-resident populations, whereas mature, terminally differentiated subsets mediate immunosurveillance through diverse peripheral sites. VIDEO ABSTRACT

    Design of Polyurethane Fibers: Relation between the Spinning Technique and the Resulting Fiber Topology

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    Masjid Kowloon: A Case Study of Coexistence Culture in Hong Kong

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    Hong Kong is an international city, located in Southern China. It used to be a British colony before 1997. While the British arrived in Hong Kong and developed it as an important seaport in the far East, Islam was believed to have spread in Hong Kong with the arrival of South Asian sailors and soldiers. Islam is not a strange religion to the Hong Kong people; it can be seen in their daily life. In Hong Kong, every people enjoys the right to practice their religion in daily life. However, due to the population structure and cultural homogeneity, people are not really familiar with Islam. Due to the negative footage in the past and an inadequate understanding of Islam, non-Muslims in Hong Kong misunderstood Muslims and caused unnecessary conflicts. The chapter aims to analyze the role of Masjid Kowloon in maintaining religious function and promoting social harmony. The chapter will use historical analysis and textual analysis to show that coexistence culture is possible in the real world, together with the analysis of prerequisites to achieving a harmonic coexistence culture in society

    Experimental Study of Broadcatching in BitTorrent

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    Abstract—Broadcatching is a promising mechanism to improve the experience of BitTorrent users by automatically downloading files advertised through RSS feeds. However, though widely used, the mechanism itself has not been well studied. In this paper, we conducted extensive experiments on PlanetLab to evaluate the performance of Broadcatching under different typical scenarios. The results demonstrated the effectiveness of the Broadcatching: it reduces the average completion time and downloading failure ratio. It also improves the overall fairness of the system: the subscribers are encouraged to share more while downloading faster, which results in the increased share ratio. Our study is the first work to systematically evaluate the benefit of Broadcatching and sheds lights on how to improve performance of BitTorrrent by manipulating peer’s behavior like Broadcatching. I

    Towards an understanding of the nature of dynamic capabilities in high-velocity markets of China

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    Dynamic capabilities are arguably of more value in the internationalization process, particularly of multinational companies (MNCs) that operate in highly dynamic international markets. Yet there is a scarcity of research on the nature of dynamic capabilities in such highly relevant contexts. This exploratory study presents observations of dynamic capabilities of MNCs operating in ten tightly-defined high-velocity industries of China that shed light on the nature of the concept. The findings suggest that (1) dynamic capabilities of MNCs in high-velocity markets are analytic, strategically planned high-frequency processes and routines, (2) they are highly complicated, and (3) they rely extensively on combined knowledge derived from global and local knowledge. They are likely influenced by diverse sources of environmental velocity and the degree of the MNC’s ownership advantages. The complexity and sophistication observed have led us to propose a way to conceptualize dynamic capabilities of MNCs in high-velocity markets

    Aggregation-Induced Emission Luminogens for Direct Exfoliation of 2D Layered Materials in Ethanol

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    © 2020 Wiley-VCH GmbH Aggregation-induced emission (AIE) luminogens are an important type of advanced functional materials with fantastic optical properties and have found potential applications in organic electronics, biochemistry, and molecular imaging. Herein, this article presents a novel application of AIE luminogens (AIEgens) for efficient exfoliation of layered transition metal dichalcogenides (TMDs, such as MoS2 and WSe2). From the 1H NMR spectroscopic analysis, the designed AIEgens can insert into the space between layers of MoS2 in ethanol solution and the dynamic molecular rotation against the weak interactions affords large-scale few-layer MoS2 nanosheets (7–8 layers) with enhanced smoothness. The 3D AIEgens play a significant role in preserving the crystal lattice of MoS2 even at high pressure (>15 GPa). More importantly, the new approach can also be used for exfoliation of WSe2 to achieve large-scale few-layer nanosheets. The present work thus provides a facile and high yielding synthetic method for accessing on a large scale 2D layered materials with enhanced properties for high-technology applications

    An Auditable Confidentiality Protocol for Blockchain Transactions

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    Blockchain exposes all users’ transaction data to the public, including account balances, asset holdings, trading history, etc. Such data exposure leads to potential security and personal privacy risks that restrict blockchain from broader adoption. Although some existing projects focus on single-chain confidential payment, no existing cross-chain system supports private transactions yet, which is incompatible with privacy regulations such as GDPR. Also, current confidential payment systems require users to pay high extra fees. However, a private and anonymous protocol encrypting all transaction data raises concerns about malicious and illegal activities since the protocol is difficult to audit. We need to balance privacy and auditability in blockchain. We propose an auditable and affordable protocol for cross-chain and single-chain transactions. This protocol leverages zero-knowledge proofs to encrypt transactions and perform validation without disclosing sensitive users\u27 data. To meet regulations, each auditor from an auditing committee will have an encrypted secret share of the transaction data. Auditors may view the private transaction data only if a majority of the committee agrees to decrypt the data. We employ a ZK-rollup scheme by processing multiple transactions in batches, which reduces private transaction costs to 90\% lower compared with solutions without ZK-rollup. We implemented the proposed scheme using Zokrates and Solidity and evaluated the protocol on the Ethereum test network, and the total one-to-one private transactions cost only 5 seconds. We also proved the security of the protocol utilizing the standard real/ideal world paradigm
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