3,937 research outputs found

    Identification of a CD11b(+)/Gr-1(+)/CD31(+) myeloid progenitor capable of activating or suppressing CD8(+) T cells

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    Apoptotic death of CD8(+) T cells can be induced by a population of inhibitory myeloid cells that are double positive for the CD11b and Gr-1 markers. These cells are responsible for the immunosuppression observed in pathologies as dissimilar as tumor growth and overwhelming infections, or after immunization with viruses. The appearance of a CD11b(+)/Gr-1(+) population of inhibitory macrophages (iMacs) could be attributed to high levels of granulocyte-macrophage colony-stimulating factor (GM-CSF) in vivo. Deletion of iMacs in vitro or in vivo reversed the depression of CD8(+) T-cell function. We isolated iMacs from the spleens of immunocompromised mice and found that these cells were positive for CD31, ER-MP20 (Ly-6C), and ER-MP58, markers characteristic of granulocyte/monocyte precursors. Importantly, although iMacs retained their inhibitory properties when cultured in vitro in standard medium, suppressive functions could be modulated by cytokine exposure. Whereas culture with the cytokine interleukin 4 (IL-4) increased iMac inhibitory activity, these cells could be differentiated into a nonadherent population of fully mature and highly activated dendritic cells when cultured in the presence of IL-4 and GM-CSF. A common CD31(+)/CD11b(+)/Gr-1(+) progenitor can thus give rise to cells capable of either activating or inhibiting the function of CD8(+) T lymphocytes, depending on the cytokine milieu that prevails during antigen-presenting cell maturation

    np-CECADA: Enhancing Ubiquitous Connectivity of LoRa Networks

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    Long Range Wide Area Networks (LoRaWAN) offer ubiquitous communications for The Internet of Things (IoT). However, there are many challenges in rolling out LoRaWAN - mainly scalability, energy efficiency, Packet Reception Ratio (PRR), and keeping the channel access as simple as unslotted ALOHA. To this end, we design non-persistent Capture Effect Channel Activity Detection Algorithm (np-CECADA), which is a novel, distributed protocol for the MAC layer of LoRaWAN. It utilizes Channel Activity Detection (CAD), which is a built-in imperfect mechanism for channel sensing and minimal feedback from the gateways. In np-CECADA each device independently adapts backoff times based on the traffic in its vicinity and the transmission power based on the heuristically inferred probability of capturing the channel. To achieve this, first, we carried out an extensive on-field evaluation to measure the effectiveness of CAD and capture effect in LoRa. Using them we designed np CECADA and developed ns-3 modules. Packet Reception Ratio of np-CECADA is 15.74× and 5.13× higher than vanilla LoRaWAN and p-CARMA, respectively. Channel utilization is 11.24× higher compared to LMAC. Further, on a testbed of 30 LoRa devices np-CECADA outperforms LoRaWAN up to 5 times.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Embedded System

    P≠NP

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    Here, the author tries to build the structure of the Theory of computation based on considering time as a fuzzy concept. In fact, there are reasons to consider time as a fuzzy concept. In this article, the author doesn’t go to this side but note that Brower and Husserl views on the concept of time were similar [8]. Some reasons have been given for it in [3]. Throughout this article, the author presents the Theory of Computation with Fuzzy Time. Given the classic definition of Turing Machine, the concept of Time is modified to Fuzzy time. This new term calls as Theory TC* [2] and this type of computation “Fuzzy time Computation”. We have relatively large number of fundamental unsolved problems in Complexity Theory. In the new theory, some of the major obstacles and unsolved problems have been solved [2]. It should be noted that in this article, the writer considers fuzzy number associated to instants of time as a symmetric one. The point about the symmetry is in the proof of Lemma 3, although it is generalizable. In particular, the new classes of complexity Theory, P*, NP*, BPP* in the TC* analogues to the definitions of P, NP, BPP defines as their natural alternative definition. Here, we will see P*≠ NP*, P*= BPP*. Finally, we have Theorem 4

    P≠NP

    No full text
    Here, the author tries to build the structure of the Theory of computation based on considering time as a fuzzy concept. In fact, there are reasons to consider time as a fuzzy concept. In this article, the author doesn’t go to this side but note that Brower and Husserl views on the concept of time were similar [8]. Some reasons have been given for it in [3]. Throughout this article, the author presents the Theory of Computation with Fuzzy Time. Given the classic definition of Turing Machine, the concept of Time is modified to Fuzzy time. This new term calls as Theory TC* [2] and this type of computation “Fuzzy time Computation”. We have relatively large number of fundamental unsolved problems in Complexity Theory. In the new theory, some of the major obstacles and unsolved problems have been solved [2]. It should be noted that in this article, the writer considers fuzzy number associated to instants of time as a symmetric one. The point about the symmetry is in the proof of Lemma 3, although it is generalizable. In particular, the new classes of complexity Theory, P*, NP*, BPP* in the TC* analogues to the definitions of P, NP, BPP defines as their natural alternative definition. Here, we will see P*≠ NP*, P*= BPP*. Finally, we have Theorem 4

    NP vyhledávací problémy

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    Title: NP search problems Author: Tomáš Jirotka Department: Department of Algebra Supervisor: Prof. RNDr. Jan Krajíček, DrSc. Abstract: The thesis summarizes known results in the field of NP search pro- blems. We discuss the complexity of integer factoring in detail, and we propose new results which place the problem in known classes and aim to separate it from PLS in some sense. Furthermore, we define several new search problems. Keywords: Computational complexity, TFNP, integer factorization.

    NP-MOVEMENT AND THE POSSESSIVE GENITIVE

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    U članku se raspravlja o mjestu genitiva u izgradnji složenih NP te posebice o odnosu s drugim konkurentnim sintaktičkim sredstvima. U žarištu istraživanja, u kojem su primijenjene neke od modularnih sastavnica teorije načela i paramatera (TNP): X'-teorija, padežna teorija i teorija tematskih uloga, nalazi se NP-pomicanje posvojnoga genitiva s temeljno generiranog položaja na mjesto odrednika, odnosno na projekciju gdje se nalazi posvojni sufiks. Autor smatra kako između DP i NP u objašnjavanju toga fenomena valja uvesti novi sloj - funkcionalnu kategoriju Poss, a NP–pomicanje objašnjava se težnjom svake imenice da bude što bolje određena, aktualizirana. Provjerava se i utjecaj morfosintaktičkog obilježja određenosti kod morfoloških posvojnih oblika na druge sročne atribute.The paper discusses the place of the genitive in the derivation of complex NPs, particularly in relation to other, competing syntactic means. The study that relies on some modular components of the theory or principles and parametres (X' theory, case theory, and the theory of thematic roles) focuses on the NP-movement of the possessive genitive out of the basegenerated position into the specifier position or into the projection occupied by the possessive suffix. The author argues that in order to explan the phenomenon a new level should be recognized between DP and NP—the functional category Poss. NP-movement is explained as the tendency of nouns to be as determined and actualised as possible. The influence of the morphosyntactic property of determination of possessive forms on other congruent attributes is examined

    Minimizing the effective graph resistance by adding links is NP-hard

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    The effective graph resistance, also known as the Kirchhoff index, is metric that is used to quantify the robustness of a network. We show that the optimisation problem of minimizing the effective graph resistance of a graph by adding a fixed number of links, is NP-hard.Quantum & Computer EngineeringNetwork Architectures and Service

    NP Photonic lasers and a new laser-frequency offset device

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    Author Institution: NP PhotonicsSlides presented at the 5th Annual Photonic Doppler Velocimetry (PDV) Users Conference held at The Ohio State University, Columbus, Ohio, September 8-9, 2010

    STRUCTURAL PECULIARITIES OF OLD ENGLISH NP IN GENERATIVE FRAMEWORK

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    The article considers peculiarities of the Old English syntax in general with the specif c reference to OE Noun phrase. The paper highlights basic structural components of NP used in Old English prose and verse. The author makes a brief comparison between structural peculiarities of NP in OE and ModE. The results of the analysis are interpreted in the light of a modern linguistic approach namely X-bar theor
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