2,317 research outputs found
Control and Filtering for Discrete Linear Repetitive Processes with H infty and ell 2--ell infty Performance
No full textRepetitive processes are characterized by a series of sweeps, termed passes, through a set of dynamics defined over a finite duration known as the pass length. On each pass an output, termed the pass profile, is produced which acts as a forcing function on, and hence contributes to, the dynamics of the next pass profile. This can lead to oscillations which increase in amplitude in the pass to pass direction and cannot be controlled by standard control laws. Here we give new results on the design of physically based control laws for the sub-class of so-called discrete linear repetitive processes which arise in applications areas such as iterative learning control. The main contribution is to show how control law design can be undertaken within the framework of a general robust filtering problem with guaranteed levels of performance. In particular, we develop algorithms for the design of an H? and dynamic output feedback controller and filter which guarantees that the resulting controlled (filtering error) process, respectively, is stable along the pass and has prescribed disturbance attenuation performance as measured by and – norms
TIM-4 is a critical EBOV receptor on peritoneal macrophages.
No full textA) TIM-4 surface expression. Matured bone marrow derived macrophages and pmacs from C57BL/6 Ifnar-/- mice were lifted from tissue culture plates, stained with directly conjugated F4/80 and CD11b mAb. Positively gated cells were analyzed for TIM-4 (grey histogram) or isotype control (white histogram) by flow cytometry. B) TIM-4 expression is required for robust rVSV/EBOV GP infection. C57BL/6 Ifnar-/- or Ifnar/Timd-4 -/- pmacs were infected with the indicated infectious units of rVSV/EBOV GP. Twenty-four hours following infection, cells were quantified for GFP expression by flow cytometry. C) Infection of BMDMs is not affected by the absence of TIM-4 expression. Bone marrow cells were isolated from C57BL/6 Ifnar-/- or Ifnar/Timd-4 -/- mice. Adherent cells were matured into macrophages by incubating for 6 days in the presence of 50ng/mL MCSF. Matured macrophages were infected with the indicated infectious units of rVSV/EBOV GP and number of infected cells were quantified by GFP expression at 24 hour following infection by flow cytometry. D) Pmacs were harvested from C57BL/6 Ifnar-/- or Ifnar/Timd-4 -/- mice and incubated with VLPs expressing EBOV GP and EBOV VP40 fused to beta lactamase. Virus/cell membrane fusion was subsequently quantified by loading cells with CCF2-AM, a β-lactam-containing fluorescent substrate, and analyzed on flow cytometry to determine the relative amount of cleaved and un-cleaved substrate. Data are shown as mean ± S.D. Statistics were calculated using Student’s t-test, *p<0.05.</p
Output Feedback Control of Discrete Linear Repetitive Processes
No full textRepetitive processes are a distinct class of 2D systems (i.e. information propagation in two independent directions) of both systems theoretic and applications interest. They cannot be controlled by direct extension of existing techniques from either standard (termed 1D here) or 2D systems theory. Here we give new results on the relatively open problem of the design of physically based control laws using an LMI setting. These results are for the sub-class of so-called discrete linear repetitive processes which arise in applications areas such as iterative learning control
TIM-1 serves as a receptor for Ebola virus in vivo, enhancing viremia and pathogenesis
No full textBackgroundT cell immunoglobulin mucin domain-1 (TIM-1) is a phosphatidylserine (PS) receptor, mediating filovirus entry into cells through interactions with PS on virions. TIM-1 expression has been implicated in Ebola virus (EBOV) pathogenesis; however, it remains unclear whether this is due to TIM-1 serving as a filovirus receptor in vivo or, as others have suggested, TIM-1 induces a cytokine storm elicited by T cell/virion interactions. Here, we use a BSL2 model virus that expresses EBOV glycoprotein to demonstrate the importance of TIM-1 as a virus receptor late during in vivo infection.Methodology/Principal findingsInfectious, GFP-expressing recombinant vesicular stomatitis virus encoding either full length EBOV glycoprotein (EBOV GP/rVSV) or mucin domain deleted EBOV glycoprotein (EBOV GPΔO/rVSV) was used to assess the role of TIM-1 during in vivo infection. GFP-expressing rVSV encoding its native glycoprotein G (G/rVSV) served as a control. TIM-1-sufficient or TIM-1-deficient BALB/c interferon α/β receptor-/- mice were challenged with these viruses. While G/rVSV caused profound morbidity and mortality in both mouse strains, TIM-1-deficient mice had significantly better survival than TIM-1-expressing mice following EBOV GP/rVSV or EBOV GPΔO/rVSV challenge. EBOV GP/rVSV or EBOV GPΔO/rVSV in spleen of infected animals was high and unaffected by expression of TIM-1. However, infectious virus in serum, liver, kidney and adrenal gland was reduced late in infection in the TIM-1-deficient mice, suggesting that virus entry via this receptor contributes to virus load. Consistent with higher virus loads, proinflammatory chemokines trended higher in organs from infected TIM-1-sufficient mice compared to the TIM-1-deficient mice, but proinflammatory cytokines were more modestly affected. To assess the role of T cells in EBOV GP/rVSV pathogenesis, T cells were depleted in TIM-1-sufficient and -deficient mice and the mice were challenged with virus. Depletion of T cells did not alter the pathogenic consequences of virus infection.ConclusionsOur studies provide evidence that at late times during EBOV GP/rVSV infection, TIM-1 increased virus load and associated mortality, consistent with an important role of this receptor in virus entry. This work suggests that inhibitors which block TIM-1/virus interaction may serve as effective antivirals, reducing virus load at late times during EBOV infection.</div
Using bacterial biomarkers to identify early indicators of cystic fibrosis pulmonary exacerbation onset
No full textAcute periods of pulmonary exacerbation are the single most important cause of morbidity in cystic fibrosis patients, and may be associated with a loss of lung function. Intervening prior to the onset of a substantially increased inflammatory response may limit the associated damage to the airways. While a number of biomarker assays based on inflammatory markers have been developed, providing useful and important measures of disease during these periods, such factors are typically only elevated once the process of exacerbation has been initiated. Identifying biomarkers that can predict the onset of pulmonary exacerbation at an early stage would provide an opportunity to intervene before the establishment of a substantial immune response, with major implications for the advancement of cystic fibrosis care. The precise triggers of pulmonary exacerbation remain to be determined; however, the majority of models relate to the activity of microbes present in the patient's lower airways of cystic fibrosis. Advances in diagnostic microbiology now allow for the examination of these complex systems at a level likely to identify factors on which biomarker assays can be based. In this article, we discuss key considerations in the design and testing of assays that could predict pulmonary exacerbations
Actor and cowboy star Will Rogers
No full textActor and cowboy Will Rogers, b&w. Typed label on back reads: The poet Lariat of America, author of WILL ROGER\u27S ILLITERATE DIGEST. It was on a flight to Alaska in 1935 with a daring one-eyed Oklahoma pilot named Wiley Post that their plane crashed and both men lost their lives.https://mds.marshall.edu/bliss_enslow_add/1133/thumbnail.jp
Decoupling and iterative approaches to the control of discrete linear repetitive processes
No full textThis paper reports new results on the analysis and control of discrete linear repetitive processes which are a distinct class of 2D discrete linear systems of both systems theoretic and applications interest. In particular, we first propose an extension to the basic state-space model to include a coupling term previously neglected but which arises in some applications and then proceed to show how computationally efficient control laws can be designed for this new model
From pattern appraisal to unitary appreciative inquiry - a critical reflection on the development of the unitary appreciative inquiry method
No full textSummative Assessment of the Core Module „Theoretical Developments in the Science and Art of Nursing“. The purpose of this article is to place Cowling’s unitary appreciative inquiry method in the context of nursing science and the development of unique nursing research methods. Unitary appreciative inquiry is one of a few nursing research and practice methodologies based on Martha Rogers’ theory, the Science of Unitary Human Beings. This article is reflecting the development of the unitary appreciative inquiry method in analyzing articles and literature published by Cowling and other authors that are related to Cowling’s ideas and approaches. A brief overview of the basic concepts, assumptions and principles of Rogers’ theory is given as well as some insights on other major influences on Cowling’s work. The changes that have been made over the past seventeen years from pattern appraisal to pattern appreciation and unitary appreciative inquiry in its current use are mapped and its contribution to current nursing knowledge and practice is critically reviewed. The author of this article strongly beliefs that nursing needs to develop its own research methods based on nursing theories for further development and improvement of nursing science as an independent and accepted discipline in human health care. It is from that perspective that Cowling’s work is reviewed
Henri Lefebvre, Space and Folklore
No full textNous explorons la pensée complexe d’Henri Lefebvre concernant l’espace, ainsi que ses implications pour les ethnologues, au moyen d’une conversation fictive entre Lefebvre et l’auteur de cet article, au cours d’une promenade dans une petite ferme du sud-est de la Colombie britannique. Certains aspects des points de vue de Lefebvre sont exposés et illustrés à partir d’exemples se présentant sur place, tels que des clôtures ou des emplacements de feux de camp. Le schéma tripartite de Lefebvre pour conceptualiser l’espace s’articule dans le cours de la conversation, en mettant en avant l’importance du concept souvent éludé d’« espace vécu ». Nous voulons démontrer que considérer l’espace de cette manière dialogique, inclusive et ouverte, amènerait à une régénération et à une approche potentiellement transformative de notre compréhension de l’espace — une approche qui aurait de nombreuses implications dans l’étude des traditions culturelles.The complex spatial thinking of Henri Lefebvre and its implications for folkloristics are explored in the context of a fictitious conversation between him and the author as they walk around a small farm in southeastern British Columbia. Aspects of Lefebvre’s position are explored and illustrated using examples from this setting, such as fences and campfire pits. Lefebvre’s tripartite schema for conceptualizing space is articulated during this conversation, foregrounding the importance of the oft-occluded espace vécu (lived space). Viewing this as a dialogic, embodied, open-ended domain of space is shown to be a highly generative and potentially transformative approach to understanding space — an approach which has numerous implications for the study of cultural tradition
- …
