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Sample records for controls integrin-mediated responses

  1. Receptor protein tyrosine phosphatase alpha activates Src-family kinases and controls integrin-mediated responses in fibroblasts

    DEFF Research Database (Denmark)

    Su, J; Muranjan, M; Sap, J

    1999-01-01

    BACKGROUND: Fyn and c-Src are two of the most widely expressed Src-family kinases. Both are strongly implicated in the control of cytoskeletal organization and in the generation of integrin-dependent signalling responses in fibroblasts. These proteins are representative of a large family of tyros......BACKGROUND: Fyn and c-Src are two of the most widely expressed Src-family kinases. Both are strongly implicated in the control of cytoskeletal organization and in the generation of integrin-dependent signalling responses in fibroblasts. These proteins are representative of a large family...... of tyrosine kinases, the activity of which is tightly controlled by inhibitory phosphorylation of a carboxyterminal tyrosine residue (Tyr527 in chicken c-Src); this phosphorylation induces the kinases to form an inactive conformation. Whereas the identity of such inhibitory Tyr527 kinases has been well...... these RPTPalpha-/- mice had impaired tyrosine kinase activity of both c-Src and Fyn, and this was accompanied by a concomitant increase in c-Src Tyr527 phosphorylation. RPTPalpha-/- fibroblasts also showed a reduction in the rate of spreading on fibronectin substrates, a trait that is a phenocopy of the effect...

  2. Integrin-mediated mechanotransduction.

    Science.gov (United States)

    Sun, Zhiqi; Guo, Shengzhen S; Fässler, Reinhard

    2016-11-21

    Cells can detect and react to the biophysical properties of the extracellular environment through integrin-based adhesion sites and adapt to the extracellular milieu in a process called mechanotransduction. At these adhesion sites, integrins connect the extracellular matrix (ECM) with the F-actin cytoskeleton and transduce mechanical forces generated by the actin retrograde flow and myosin II to the ECM through mechanosensitive focal adhesion proteins that are collectively termed the "molecular clutch." The transmission of forces across integrin-based adhesions establishes a mechanical reciprocity between the viscoelasticity of the ECM and the cellular tension. During mechanotransduction, force allosterically alters the functions of mechanosensitive proteins within adhesions to elicit biochemical signals that regulate both rapid responses in cellular mechanics and long-term changes in gene expression. Integrin-mediated mechanotransduction plays important roles in development and tissue homeostasis, and its dysregulation is often associated with diseases. © 2016 Sun et al.

  3. Endosomes: Emerging Platforms for Integrin-Mediated FAK Signalling.

    Science.gov (United States)

    Alanko, Jonna; Ivaska, Johanna

    2016-06-01

    Integrins are vital cell adhesion receptors with the ability to transmit extracellular matrix (ECM) cues to intracellular signalling pathways. ECM-integrin signalling regulates various cellular functions such as cell survival and movement. Integrin signalling has been considered to occur exclusively from adhesion sites at the plasma membrane (PM). However, recent data demonstrates integrin signalling also from endosomes. Integrin-mediated focal adhesion kinase (FAK) signalling is strongly dependent on integrin endocytosis, and endosomal FAK signalling facilitates cancer metastasis by supporting anchorage-independent growth and anoikis resistance. Here we discuss the possible mechanisms and functions of endosomal FAK signalling compared with its previously known roles in other cellular locations and discuss the potential of endosomal FAK as novel target for future cancer therapies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Participation of caveolae in beta1 integrin-mediated mechanotransduction.

    Science.gov (United States)

    Radel, Chris; Carlile-Klusacek, Maryellen; Rizzo, Victor

    2007-06-29

    We previously reported that caveolin-1 is a key component in a beta1 integrin-dependent mechanotransduction pathway suggesting that caveolae organelles and integrins are functionally linked in their mechanotransduction properties. Here, we exposed BAEC monolayers to shear stress then isolated caveolae vesicles form the plasma membrane. While little beta1 integrin was detected in caveolae derived from cells kept in static culture, shear stress induced beta1 integrin transposition to the caveolae. To evaluate the significance of shear-induced beta1 integrin localization to caveolae, cells were pretreated with cholesterol sequestering compounds or caveolin-1 siRNA to disrupt caveolae structural domains. Cholesterol depletion attenuated integrin-dependent caveolin-1 phosphorylation, Src activation and Csk association with beta1 integrin. Reduction of both caveolin-1 protein and membrane cholesterol inhibited downstream shear-induced, integrin-dependent phosphorylation of myosin light chain. Taken together with our previous findings, the data supports the concept that beta1 integrin-mediated mechanotransduction is mediated by caveolae domains.

  5. Participation of caveolae in β1 integrin-mediated mechanotransduction

    Science.gov (United States)

    Radel, Chris; Carlile-Klusacek, MaryEllen; Rizzo, Victor

    2007-01-01

    We previously reported that caveolin-1 is a key component in a β1 integrin-dependent mechanotransduction pathway suggesting that caveolae organelles and integrins are functionally linked in their mechanotransduction properties. Here, we exposed BAEC monolayers to shear stress then isolated caveolae vesicles form the plasma membrane. While little β1 integrin was detected in caveolae derived from cells kept in static culture, shear stress induced β1 integrin transposition to the caveolae. To evaluate the significance of shear-induced β1 integrin localization to caveolae, cells were pretreated with cholesterol sequestering compounds or caveolin-1 siRNA to disrupt caveolae structural domains. Cholesterol depletion attenuated integrin-dependent caveolin-1 phosphorylation, Src activation and Csk association with β1 integrin. Reduction of both caveolin-1 protein and membrane cholesterol inhibited downstream shear-induced, integrin–dependent phosphorylation of myosin light chain. Taken together with our previous findings, the data supports the concept that β1 integrin-mediated mechanotransduction is mediated by caveolae domains. PMID:17498653

  6. A proteomics view on integrin-mediated adhesions.

    Science.gov (United States)

    Manninen, Aki; Varjosalo, Markku

    2017-02-01

    Individual cells in multicellular organisms constantly explore their microenvironment, or niche, to obtain spatial information that is used to regulate cell behavior to maintain tissue integrity. The extracellular matrix (ECM) is an important source of such spatial information. Binding of the integrin family receptors to the ECM triggers formation of integrin adhesion complexes (IACs) that link the ECM network to cellular cytoskeleton via remarkably large multiprotein complexes collectively referred to as the integrin adhesome. Recent advances in proteomics have enabled researchers to study the IAC composition in detail. Various biochemical IAC isolation methods and culture conditions have been employed to study the composition and dynamics of integrin-mediated adhesions mainly in fibroblasts and lymphoblasts. These studies have led to identification of daunting lists of potential IAC components. This review focuses on the current status of proteomics-driven research seeking to understand integrin functions by comprehensive analysis of IAC components. These systems level approaches have revealed the complexity of biochemical and biomechanical signals that are processed at IACs and provide a novel insight into how these signals are conveyed to regulate cellular behavior. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Integrin-mediated cell surface recruitment of autotaxin promotes persistent directional cell migration

    Science.gov (United States)

    Wu, Tao; Kooi, Craig Vander; Shah, Pritom; Charnigo, Richard; Huang, Cai; Smyth, Susan S.; Morris, Andrew J.

    2014-01-01

    Autotaxin (ATX) is a secreted lysophospholipase D (lysoPLD) that binds to integrin adhesion receptors. We dissected the roles of integrin binding and lysoPLD activity in stimulation of human breast cancer and mouse aortic vascular smooth muscle cell migration by ATX. We compared effects of wild-type human ATX, catalytically inactive ATX, an integrin binding-defective ATX variant with wild-type lysoPLD activity, the isolated ATX integrin binding N-terminal domain, and a potent ATX selective lysoPLD inhibitor on cell migration using transwell and single-cell tracking assays. Stimulation of transwell migration was reduced (18 or 27% of control, respectively) but not ablated by inactivation of integrin binding or inhibition of lysoPLD activity. The N-terminal domain increased transwell migration (30% of control). ATX lysoPLD activity and integrin binding were necessary for a 3.8-fold increase in the fraction of migrating breast cancer cell step velocities >0.7 μm/min. ATX increased the persistent directionality of single-cell migration 2-fold. This effect was lysoPLD activity independent and recapitulated by the integrin binding N-terminal domain. Integrin binding enables uptake and intracellular sequestration of ATX, which redistributes to the front of migrating cells. ATX binding to integrins and lysoPLD activity therefore cooperate to promote rapid persistent directional cell migration.—Wu, T., Kooi, C. V., Shah, P., Charnigo, R., Huang, C., Smyth, S. S., Morris, A. J. Integrin-mediated cell surface recruitment of autotaxin promotes persistent directional cell migration. PMID:24277575

  8. Integrin-mediated targeting of protein polymer nanoparticles carrying a cytostatic macrolide

    Science.gov (United States)

    Shi, Pu

    chapter illustrates how to tune the ELP sequence and architecture for either coassembly or sorting of distinct proteins into microdomains within a living cell. Passive tumor targeting utilizing enhanced permeability and retention (EPR) effect has limited efficiency in targeting non-leaky tumors such as MDA-MB-468 breast tumor; however, an RGD tri-peptide decorated micelle nanoparticle can effectively accumulate in tumor site via integrin-mediated active tumor targeting. Different from inefficient and cytotoxic chemical linkage reactions, an elastin-based multi-functional nanocarrier can be assembled by genetic protein fusion and micelle co-assembly technology. The novel drug carrier contains the cognate Rapamycin (Rapa) receptor -- FK506 binding protein (FKBP) as the high-avidity drug binding domain and an RGD peptide as the active tumor targeting domain. Here we show that by co-assembling FKBP and RGD contained protein polymers into mixed micelle nanoparticles, they not only competently targeted endothelial and tumor cells in cell assays, but specifically delivered the drug with a slow release half-life of 38h. It was demonstrated that the active tumor targeting formulation of Rapa more effectively suppressed tumor growth compared to the passive tumor targeting formulation and free drug in tumor regression studies of mouse MDA-MB-468 xenografts. We believe that the exciting results will provide a new tool for the development of next-generation "smart" multi-functional drug carriers. (Abstract shortened by UMI.).

  9. Molecular mechanisms of mechanotransduction in integrin-mediated cell-matrix adhesion.

    Science.gov (United States)

    Li, Zhenhai; Lee, Hyunjung; Zhu, Cheng

    2016-11-15

    Cell-matrix adhesion complexes are multi-protein structures linking the extracellular matrix (ECM) to the cytoskeleton. They are essential to both cell motility and function by bidirectionally sensing and transmitting mechanical and biochemical stimulations. Several types of cell-matrix adhesions have been identified and they share many key molecular components, such as integrins and actin-integrin linkers. Mechanochemical coupling between ECM molecules and the actin cytoskeleton has been observed from the single cell to the single molecule level and from immune cells to neuronal cells. However, the mechanisms underlying force regulation of integrin-mediated mechanotransduction still need to be elucidated. In this review article, we focus on integrin-mediated adhesions and discuss force regulation of cell-matrix adhesions and key adaptor molecules, three different force-dependent behaviors, and molecular mechanisms for mechanochemical coupling in force regulation. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Integrin-mediated internalization of Staphylococcus aureus does not require vinculin

    Directory of Open Access Journals (Sweden)

    Borisova Marina

    2013-01-01

    Full Text Available Abstract Background Disease manifestations of Staphylococcus aureus are connected to the fibronectin (Fn-binding capacity of these Gram-positive pathogens. Fn deposition on the surface of S. aureus allows engagement of α5β1 integrins and triggers uptake by host cells. For several integrin- and actin-associated cytoplasmic proteins, including FAK, Src, N-WASP, tensin and cortactin, a functional role during bacterial invasion has been demonstrated. As reorganization of the actin cytoskeleton is critical for bacterial entry, we investigated whether vinculin, an essential protein linking integrins with the actin cytoskeleton, may contribute to the integrin-mediated internalization of S. aureus. Results Complementation of vinculin in vinculin -/- cells, vinculin overexpression, as well as shRNA-mediated vinculin knock-down in different eukaryotic cell types demonstrate, that vinculin does not have a functional role during the integrin-mediated uptake of S. aureus. Conclusions Our results suggest that vinculin is insignificant for the integrin-mediated uptake of S. aureus despite the critical role of vinculin as a linker between integrins and F-actin.

  11. Reinforcement of integrin-mediated T-Lymphocyte adhesion by TNF-induced Inside-out Signaling.

    Science.gov (United States)

    Li, Qian; Huth, Steven; Adam, Dieter; Selhuber-Unkel, Christine

    2016-07-28

    Integrin-mediated leukocyte adhesion to endothelial cells is a crucial step in immunity against pathogens. Whereas the outside-in signaling pathway in response to the pro-inflammatory cytokine tumour necrosis factor (TNF) has already been studied in detail, little knowledge exists about a supposed TNF-mediated inside-out signaling pathway. In contrast to the outside-in signaling pathway, which relies on the TNF-induced upregulation of surface molecules on endothelium, inside-out signaling should also be present in an endothelium-free environment. Using single-cell force spectroscopy, we show here that stimulating Jurkat cells with TNF significantly reinforces their adhesion to fibronectin in a biomimetic in vitro assay for cell-surface contact times of about 1.5 seconds, whereas for larger contact times the effect disappears. Analysis of single-molecule ruptures further demonstrates that TNF strengthens sub-cellular single rupture events at short cell-surface contact times. Hence, our results provide quantitative evidence for the significant impact of TNF-induced inside-out signaling in the T-lymphocyte initial adhesion machinery.

  12. Extracellular Alix regulates integrin-mediated cell adhesions and extracellular matrix assembly.

    Science.gov (United States)

    Pan, Shujuan; Wang, Ruoning; Zhou, Xi; Corvera, Joe; Kloc, Malgorzata; Sifers, Richard; Gallick, Gary E; Lin, Sue-Hwa; Kuang, Jian

    2008-08-06

    Alix (ALG-2-interacting protein X), a cytoplasmic adaptor protein involved in endosomal sorting and actin cytoskeleton assembly, is required for the maintenance of fibroblast morphology. As Alix has sequence similarity to adhesin in Entamoeba histolytica, and we observed that Alix is secreted, we determined whether extracellular Alix affects fibroblast morphology. Here, we demonstrate that secreted Alix is deposited on the substratum of non-immortalized WI38 fibroblasts. Antibody binding to extracellular Alix retards WI38 cell adhesion and spreading on fibronectin and vitronectin. Alix knockdown in WI38 cells reduces spreading and fibronectin assembly, and the effect is partially complemented by coating recombinant Alix on the cell substratum. Immortalized NIH/3T3 fibroblasts deposit less Alix on the substratum and have defects in alpha5beta1-integrin functions. Coating recombinant Alix on the culture substratum for NIH/3T3 cells promotes alpha5beta1-integrin-mediated cell adhesions and fibronectin assembly, and these effects require the aa 605-709 region of Alix. These findings demonstrate that a sub-population of Alix localizes extracellularly and regulates integrin-mediated cell adhesions and fibronectin matrix assembly.

  13. Stromal cell-derived factor-1 (SDF-1) enhances cells invasion by αvβ6 integrin-mediated signaling in ovarian cancer.

    Science.gov (United States)

    Xue, Baoyao; Wu, Weiguang; Huang, Kan; Xie, Tingting; Xu, Xiaobo; Zhang, Hongju; Qi, Chunlei; Ge, Junli; Yu, Yuecheng

    2013-08-01

    Ovarian carcinoma is a common gynecological malignancy and a great threat to health as a result of metastasis. The chemokine stromal-derived factor (SDF-1) plays multiple roles in tumor pathogenesis. However, the precise molecular mechanism underlying SDF-1-induced ovarian cancer cell invasion is still undefined. αvβ6 integrin is an important factor in tumor progression. Therefore, we speculate that SDF-1-enhanced ovarian cancer cell invasion is related to αvβ6 integrin-mediated signaling. After culturing with SDF-1, an obvious time- and dose-dependent increase in αvβ6 integrin was demonstrated. Furthermore, CXC receptor 4 (CXCR4) was responsible for SDF-1-induced αvβ6 integrin expression. Simultaneously, SDF-1 was found to dramatically enhance extracellular matrix degradation via urokinase-type plasminogen activator (uPA) expression and cell invasion by αvβ6 integrin expression; these reinforce failed to be increased when pretreatment was performed with the CXCR4 inhibitor AMD3100 or anti-αvβ6 integrin antibody, respectively. In addition, αvβ6 integrin induced the phosphorylation of p38 MAPK and PI3 K/Akt, contributing to the up-regulation of uPA, as treatment with the specific inhibitor for p38 mitogen-activated protein kinases (MAPK) (SB203580) or phosphatidylinositol 3-kinase (PI3 K)/Akt (LY294002) strikingly abrogated uPA expression. Taken together, these results demonstrated that SDF-1 enhanced ovarian cancer cell invasion through αvβ6 integrin-mediated uPA expression via the p38 MAPK and PI3 K/Akt pathway. Consequently, our findings will provide a new explanation about how SDF-1 aggravates the pathogenesis of ovarian cancer.

  14. Integrin-mediated cell migration is blocked by inhibitors of human neuraminidase.

    Science.gov (United States)

    Jia, Feng; Howlader, Md Amran; Cairo, Christopher W

    2016-09-01

    Integrins are critical receptors in cell migration and adhesion. A number of mechanisms are known to regulate the function of integrins, including phosphorylation, conformational change, and cytoskeletal anchoring. We investigated whether native neuraminidase (Neu, or sialidase) enzymes which modify glycolipids could play a role in regulating integrin-mediated cell migration. Using a scratch assay, we found that exogenously added Neu3 and Neu4 activity altered rates of cell migration. We observed that Neu4 increased the rate of migration in two cell lines (HeLa, A549); while Neu3 only increased migration in HeLa cells. A bacterial neuraminidase was able to increase the rate of migration in HeLa, but not in A549 cells. Treatment of cells with complex gangliosides (GM1, GD1a, GD1b, and GT1b) resulted in decreased cell migration rates, while LacCer was able to increase rates of migration in both lines. Importantly, our results show that treatment of cells with inhibitors of native Neu enzymes had a dramatic effect on the rates of cell migration. The most potent compound tested targeted the human Neu4 isoenzyme, and was able to substantially reduce the rate of cell migration. We found that the lateral mobility of integrins was reduced by treatment of cells with Neu3, suggesting that Neu3 enzyme activity resulted in changes to integrin-co-receptor or integrin-cytoskeleton interactions. Finally, our results support the hypothesis that inhibitors of human Neu can be used to investigate mechanisms of cell migration and for the development of anti-adhesive therapies. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Endoglin involvement in integrin-mediated cell adhesion as a putative pathogenic mechanism in Hereditary Hemorrhagic Telangectasia type 1 (HHT1

    Directory of Open Access Journals (Sweden)

    Elisa eRossi

    2015-01-01

    Full Text Available Mutations in the endoglin gene (ENG are responsible for approximately 50% of all cases with Hereditary Hemorrhagic Telangectasia (HHT. Because of the absence of effective treatments for HHT symptoms, studies aimed at identifying novel biological functions of endoglin which could serve as therapeutic targets of the disease are needed. Endoglin is an endothelial membrane protein, whose most studied function has been its role as an auxiliary receptor in the TGF-β receptor complex. However, several lines of evidence suggest the involvement of endoglin in TGF-β-independent functions. Endoglin displays, within its zona pellucida (ZP domain, an RGD motif, which is a prototypic sequence involved in integrin-based interactions with other proteins. Indeed, we have recently described a novel role for endothelial endoglin in leukocyte trafficking and extravasation via its interaction with leukocyte integrins. In addition, functional, as well as protein and gene expression analysis have shown that ectopic endoglin represses the synthesis of several members of the integrin family and modulates integrin-mediated cell adhesions. This review focuses on the tight link between endoglin and integrins and how the role of endothelial endoglin in integrin-dependent cell adhesion processes can provide a better understanding of the pathogenic mechanisms leading to vascular lesions in endoglin haploinsufficient HHT1 patients.

  16. The PI3-kinase delta inhibitor idelalisib (GS-1101) targets integrin-mediated adhesion of chronic lymphocytic leukemia (CLL) cell to endothelial and marrow stromal cells.

    Science.gov (United States)

    Fiorcari, Stefania; Brown, Wells S; McIntyre, Bradley W; Estrov, Zeev; Maffei, Rossana; O'Brien, Susan; Sivina, Mariela; Hoellenriegel, Julia; Wierda, William G; Keating, Michael J; Ding, Wei; Kay, Neil E; Lannutti, Brian J; Marasca, Roberto; Burger, Jan A

    2013-01-01

    CLL cell trafficking between blood and tissue compartments is an integral part of the disease process. Idelalisib, a phosphoinositide 3-kinase delta (PI3Kδ) inhibitor causes rapid lymph node shrinkage, along with an increase in lymphocytosis, prior to inducing objective responses in CLL patients. This characteristic activity presumably is due to CLL cell redistribution from tissues into the blood, but the underlying mechanisms are not fully understood. We therefore analyzed idelalisib effects on CLL cell adhesion to endothelial and bone marrow stromal cells (EC, BMSC). We found that idelalisib inhibited CLL cell adhesion to EC and BMSC under static and shear flow conditions. TNFα-induced VCAM-1 (CD106) expression in supporting layers increased CLL cell adhesion and accentuated the inhibitory effect of idelalisib. Co-culture with EC and BMSC also protected CLL from undergoing apoptosis, and this EC- and BMSC-mediated protection was antagonized by idelalisib. Furthermore, we demonstrate that CLL cell adhesion to EC and VLA-4 (CD49d) resulted in the phosphorylation of Akt, which was sensitive to inhibition by idelalisib. These findings demonstrate that idelalisib interferes with integrin-mediated CLL cell adhesion to EC and BMSC, providing a novel mechanism to explain idelalisib-induced redistribution of CLL cells from tissues into the blood.

  17. Ubc9 Binds to ADAP and Is Required for Rap1 Membrane Recruitment, Rac1 Activation, and Integrin-Mediated T Cell Adhesion.

    Science.gov (United States)

    Xiong, Yiwei; Ye, Chengjin; Yang, Naiqi; Li, Madanqi; Liu, Hebin

    2017-11-10

    Although the immune adaptor adhesion and degranulation-promoting adaptor protein (ADAP) acts as a key mediator of integrin inside-out signaling leading to T cell adhesion, the regulation of this adaptor during integrin activation and clustering remains unclear. We now identify Ubc9, the sole small ubiquitin-related modifier E2 conjugase, as an essential regulator of ADAP where it is required for TCR-induced membrane recruitment of the small GTPase Rap1 and its effector protein RapL and for activation of the small GTPase Rac1 in T cell adhesion. We show that Ubc9 interacted directly with ADAP in vitro and in vivo, and the association was increased in response to anti-CD3 stimulation. The Ubc9-binding domain on ADAP was mapped to a nuclear localization sequence (aa 674-700) within ADAP. Knockdown of Ubc9 by short hairpin RNA or expression of the Ubc9-binding-deficient ADAP mutant significantly decreased TCR-induced integrin adhesion to ICAM-1 and fibronectin, as well as LFA-1 clustering, although it had little effect on the TCR proximal signaling responses and TCR-induced IL-2 transcription. Furthermore, downregulation of Ubc9 impaired TCR-mediated Rac1 activation and attenuated the membrane targeting of Rap1 and RapL, but not Rap1-interacting adaptor molecule. Taken together, our data demonstrate for the first time, to our knowledge, that Ubc9 acts as a functional binding partner of ADAP and plays a selective role in integrin-mediated T cell adhesion via modulation of Rap1-RapL membrane recruitment and Rac1 activation. Copyright © 2017 by The American Association of Immunologists, Inc.

  18. Carbon nanotube-composite hydrogels promote intercalated disc assembly in engineered cardiac tissues through β1-integrin mediated FAK and RhoA pathway.

    Science.gov (United States)

    Sun, Hongyu; Tang, Jiajia; Mou, Yongchao; Zhou, Jing; Qu, Linlin; Duval, Kayla; Huang, Zhu; Lin, Ning; Dai, Ruiwu; Liang, Chengxiao; Chen, Zi; Tang, Lijun; Tian, Fuzhou

    2017-01-15

    Carbon nanotube (CNT)-based hydrogels have been shown to support cardiomyocyte growth and function. However, their role in cellular integrity among cardiomyocytes has not been studied in detail and the mechanisms underlying this process remain unclear. Here, single walled CNTs incorporated into gelatin with methacrylate anhydride (CNT/GelMA) hydrogels were utilized to construct cardiac tissues, which enhanced cardiomyocyte adhesion and maturation. Furthermore, through the use of immunohistochemical staining, transmission electron microscopy and intracellular calcium transient measurement, the incorporation of CNTs into the scaffolds was observed to markedly enhance the assembly and formation in the cardiac constructs. Importantly, we further explored the underlying mechanism behind these effects through the use of immunohistochemical staining and western blotting. The β1-integrin-mediated FAK and RhoA signaling pathways were found to be responsible for CNT-induced upregulation of electrical and mechanical junction proteins respectively. Together, our study provides new insights into the facilitative effects of CNTs on ID formation, which has important significance for improving the quality of engineered cardiac tissue and applying them to cardiac regenerative therapies. Currently, the bottleneck to engineering cardiac tissues (ECTs) for cardiac regeneration is the lack of efficient cellular integrity among adjacent cells, especially the insufficient remodeling of intercalated discs (IDs) in ECTs. Recently, carbon nanotube (CNT) hydrogels provide an advantageous supporting microenvironment and therefore benefit greatly the functional performance of ECTs. Although their beneficial effect in modulating ECT performance is evident, the influence of CNTs on structural integrity of ECTs has not been studied in detail, and the mechanisms underlying the process remain to be determined. Here, we utilized carbon nanotube incorporated into gelatin with methacrylate anhydride

  19. β-1 Integrin-Mediated Adhesion May Be Initiated by Multiple Incomplete Bonds, Thus Accounting for the Functional Importance of Receptor Clustering

    OpenAIRE

    Vitte, Joana; Benoliel, Anne-Marie; Eymeric, Philippe; Bongrand, Pierre; Pierres, Anne

    2004-01-01

    The regulation of cell integrin receptors involves modulation of membrane expression, shift between different affinity states, and topographical redistribution on the cell membrane. Here we attempted to assess quantitatively the functional importance of receptor clustering. We studied β-1 integrin-mediated attachment of THP-1 cells to fibronectin-coated surfaces under low shear flow. Cells displayed multiple binding events with a half-life of the order of 1 s. The duration of binding events a...

  20. beta1-integrin mediates myelin-associated glycoprotein signaling in neuronal growth cones

    Directory of Open Access Journals (Sweden)

    Goh Eyleen LK

    2008-10-01

    Full Text Available Abstract Several myelin-associated factors that inhibit axon growth of mature neurons, including Nogo66, myelin-associated glycoprotein (MAG and oligodendrocyte myelin glycoprotein (OMgp, can associate with a common GPI-linked protein Nogo-66 receptor (NgR. Accumulating evidence suggests that myelin inhibitors also signal through unknown NgR-independent mechanisms. Here we show that MAG, a RGD tri-peptide containing protein, forms a complex with β1-integrin to mediate axonal growth cone turning responses of several neuronal types. Mutations that alter the RGD motif in MAG or inhibition of β1-integrin function, but not removal of NgRs, abolish these MAG-dependent events. In contrast, OMgp-induced repulsion is not affected by inhibition of b1-integrin function. We further show that MAG stimulates tyrosine phosphorylation of focal adhesion kinase (FAK, which in turn is required for MAG-induced growth cone turning. These studies identify β1-integrin as a specific mediator for MAG in growth cone turning responses, acting through FAK activation.

  1. Assessment of the effect of potential antifibrotic compounds on total and αVβ6 integrin-mediated TGF-β activation.

    Science.gov (United States)

    Porte, Joanne; Jenkins, Gisli

    2014-08-01

    Transforming growth factor-β (TGF-β) plays an important role in the development of tissue fibrosis, and molecules inhibiting this pathway are attractive therapeutic targets for fibrotic diseases such as idiopathic pulmonary fibrosis (IPF). Activation of TGF-β is the rate-limiting step in TGF-β bioavailability, and activation by the αVβ6 integrin is important in fibrosis of the lung, liver, and kidney. Activation of TGF-β by αVβ6 requires direct cell-cell contact and measurable release of active TGF-β in extracellular fluid compartments does not reflect tissue specific activation. The aim of this study was to determine the effect of antifibrotic compounds on both total, and specific αVβ6 integrin-mediated TGF-β activity. Using a transformed mink lung cell (TMLC) TGF-β reporter, the effects of potential antifibrotic therapies including an activin-like kinase (Alk5) inhibitor, Dexamethasone, Pirfenidone, N-acetylcysteine (NAC), and BIBF1120 were assessed. Effects due to αVβ6 integrin-mediated TGF-β activity were measured using reporter cells cocultured with cells expressing αVβ6 integrins. These high-throughput studies were validated using a phosphorylated Smad2 Enzyme-Linked Immunosorbent Assay. Alk5 inhibitors are potent inhibitors of TGF-β activity, whereas the novel antifibrotics, Pirfenidone, BIBF1120, and NAC are only moderate inhibitors, and Dexamethasone does not specifically affect TGF-βactivity, but inhibits TGF-β-induced gene expression. None of the current small molecular inhibitors inhibit αVβ6-mediated TGF-β activity. These results demonstrate the potential of this high-throughput assay of αVβ6-specific TGF-β activity and illustrate that currently available antifibrotics have limited effects on αVβ6 integrin-mediated TGF-β activity.

  2. Effect of hypoxia on integrin-mediated adhesion of endothelial progenitor cells.

    Science.gov (United States)

    Kaiser, Ralf; Friedrich, Denise; Chavakis, Emmanouil; Böhm, Michael; Friedrich, Erik B

    2012-10-01

    Homing of endothelial progenitor cells (EPCs) is crucial for neoangiogenesis, which might be negatively affected by hypoxia. We investigated the influence of hypoxia on fibronectin binding integrins for migration and cell-matrix-adhesion. AMP-activated kinase (AMPK) and integrin-linked kinase (ILK) were examined as possible effectors of hypoxia. Human EPCs were expanded on fibronectin (FN) and integrin expression was profiled by flow cytometry. Cell-matrix-adhesion- and migration-assays on FN were performed to examine the influence of hypoxia and AMPK-activation. Regulation of AMPK and ILK was shown by Western blot analysis. We demonstrate the presence of integrin β(1), β(2) and α(5) on EPCs. Adhesion to FN is reduced by blocking β(1) and α(5) (49% and 2% of control, P effect. Corresponding effects were shown for migration. Hypoxia and AMPK-activation decrease adhesion on FN. Although total AMPK-expression remains unchanged, phospho-AMPK increases eightfold. The EPCs require α(5) for adhesion on FN. Hypoxia and AMPK-activation decrease adhesion. As α(5) is the major adhesive factor for EPCs on FN, this suggests a link between AMPK and α(5)-integrins. We found novel evidence for a connection between hypoxia, AMPK-activity and integrin activity. This might affect the fate of EPCs in ischaemic tissue. © 2012 The Authors Journal of Cellular and Molecular Medicine © 2012 Foundation for Cellular and Molecular Medicine/Blackwell Publishing Ltd.

  3. Type VI collagen increases cell survival and prevents anti-beta 1 integrin-mediated apoptosis.

    Science.gov (United States)

    Howell, S J; Doane, K J

    1998-05-25

    Cell-matrix interactions are important in the development of the avian cornea. Type VI collagen is present within the periocular mesenchyme prior to the migration of cells into the corneal stroma and is abundant in the mature stroma. Whether the interaction of cells with type VI collagen is essential for cellular survival in the cornea is not known. In the present study, we examined the interaction of corneal cells with type VI collagen in vitro to determine if it can increase cell proliferation and decrease apoptosis. In vivo analysis demonstrated that apoptosis occurs in the periocular region during early stages of avian corneal development, but in fully mature corneas apoptosis only occurs in the corneal epithelium and not in the stroma. In vitro analysis examined the importance of beta 1 integrin interactions with type VI collagen in mature corneal fibroblasts and the precursor cells. Using an anti-beta 1 integrin blocking antibody, CSAT, integrin/matrix interactions were disrupted. Results indicated that viability of both corneal fibroblasts and periocular mesenchyme cells was greater on type VI collagen than on type I collagen or BSA-blocked glass. In addition, less apoptosis was observed for both cell types on type VI collagen when beta 1 integrin--matrix interactions were disrupted. These data indicated that these cells require intact beta 1 interactions with type I collagen and with BSA-coated glass controls to remain viable. Thus, type VI collagen may play a role in the rescue of corneal cells from anti-beta 1 integrin-induced apoptosis by increasing cell survival, probably via a non-beta 1 integrin-dependent mechanism.

  4. Integrin-mediated mechanotransduction

    National Research Council Canada - National Science Library

    Sun, Zhiqi; Guo, Shengzhen S; Fässler, Reinhard

    2016-01-01

      Cells can detect and react to the biophysical properties of the extracellular environment through integrin-based adhesion sites and adapt to the extracellular milieu in a process called mechanotransduction...

  5. Beta-1 integrin-mediated adhesion may be initiated by multiple incomplete bonds, thus accounting for the functional importance of receptor clustering.

    Science.gov (United States)

    Vitte, Joana; Benoliel, Anne-Marie; Eymeric, Philippe; Bongrand, Pierre; Pierres, Anne

    2004-06-01

    The regulation of cell integrin receptors involves modulation of membrane expression, shift between different affinity states, and topographical redistribution on the cell membrane. Here we attempted to assess quantitatively the functional importance of receptor clustering. We studied beta-1 integrin-mediated attachment of THP-1 cells to fibronectin-coated surfaces under low shear flow. Cells displayed multiple binding events with a half-life of the order of 1 s. The duration of binding events after the first second after arrest was quantitatively accounted for by a model assuming the existence of a short-time intermediate binding state with 3.6 s(-1) dissociation rate and 1.3 s(-1) transition frequency toward a more stable state. Cell binding to surfaces coated with lower fibronectin densities was concluded to be mediated by single molecular interactions, whereas multiple bonds were formed Cell treatment with microfilament inhibitors or a neutral antiintegrin antibody decreased bond number without changing aforementioned kinetic parameters whereas a function enhancing antibody increased the rate of bond formation and/or the lifetime of intermediate state. Receptor aggregation was induced by treating cells with neutral antiintegrin antibody and antiimmunoglobulin antibodies. A semiquantitative confocal microscopy study suggested that this treatment increased between 40% and 100% the average number of integrin receptors located in a volume of approximately 0.045 microm(3) surrounding each integrin. This aggregation induced up to 2.7-fold increase of the average number of bonds. Flow cytometric analysis of fluorescent ligand binding showed that THP-1 cells displayed low-affinity beta-1 integrins with a dissociation constant in the micromolar range. It is concluded that the initial step of cell adhesion was mediated by multiple incomplete bonds rather than a single equilibrium-state ligand receptor association. This interpretation accounts for the functional

  6. Effect of alpha 2,6 sialylation on integrin-mediated adhesion of breast cancer cells to fibronectin and collagen IV.

    Science.gov (United States)

    Yuan, Ye; Wu, Larry; Shen, Siqi; Wu, Shiyong; Burdick, Monica M

    2016-03-15

    To determine the role of sialylation on α5β1 and α2β1 integrins in the regulation of adhesion between breast cancer cells and extracellular matrix (ECM). Static cell adhesion assays were performed to quantify avidity of breast cancer cells to ECM. The effects of sialidases on α2,6 sialylation was assessed by flow cytometry using biotin conjugated Sambucus nigra lectin. Lectin affinity assays were used to determine expression of α2,6 sialylated integrins. Cell migration and invasion were investigated by wound healing and transwell invasion assays. α2, α5 and β1 integrins had considerable α2,6 sialylation on MDA-MB-231 cells, whereas signals from MCF-7 cells were undetectable. Cleavage of α2,6 sialylation increased adhesion of MDA-MB-231 cells to ECM, while adhesion of MCF-7 cells was unaffected, consistent with the latter's lack of endogenous α2,6 sialylated surface integrins. Neither surface expression of α2β1 and α5β1 integrins, nor activated β1 integrin, changed in MDA-MB-231 cells after sialidase treatment. However, sialidase treatment did not have significant impact on migration or invasion of MDA-MB-231 cells. Cell adhesion is an important early step of cancer metastasis, yet the roles of sialylation in regulating integrin-mediated breast cancer cell adhesion in comparison to migration and invasion are not well-understood. Our data suggest desialylation of α2,6-sialylated integrins increases adhesion, but not migration or invasion, of MDA-MB-231 cells to ECM without altering integrin expression. It should be considered that α2,6 sialylation may play different roles in regulating cell adhesion of different cancer cells when developing potential therapeutics targeting α2,6 sialylation. Published by Elsevier Inc.

  7. β2 integrin-mediated crawling on endothelial ICAM-1 and ICAM-2 is a prerequisite for transcellular neutrophil diapedesis across the inflamed blood-brain barrier.

    Science.gov (United States)

    Gorina, Roser; Lyck, Ruth; Vestweber, Dietmar; Engelhardt, Britta

    2014-01-01

    In acute neuroinflammatory states such as meningitis, neutrophils cross the blood-brain barrier (BBB) and contribute to pathological alterations of cerebral function. The mechanisms that govern neutrophil migration across the BBB are ill defined. Using live-cell imaging, we show that LPS-stimulated BBB endothelium supports neutrophil arrest, crawling, and diapedesis under physiological flow in vitro. Investigating the interactions of neutrophils from wild-type, CD11a(-/-), CD11b(-/-), and CD18(null) mice with wild-type, junctional adhesion molecule-A(-/-), ICAM-1(null), ICAM-2(-/-), or ICAM-1(null)/ICAM-2(-/-) primary mouse brain microvascular endothelial cells, we demonstrate that neutrophil arrest, polarization, and crawling required G-protein-coupled receptor-dependent activation of β2 integrins and binding to endothelial ICAM-1. LFA-1 was the prevailing ligand for endothelial ICAM-1 in mediating neutrophil shear resistant arrest, whereas Mac-1 was dominant over LFA-1 in mediating neutrophil polarization on the BBB in vitro. Neutrophil crawling was mediated by endothelial ICAM-1 and ICAM-2 and neutrophil LFA-1 and Mac-1. In the absence of crawling, few neutrophils maintained adhesive interactions with the BBB endothelium by remaining either stationary on endothelial junctions or displaying transient adhesive interactions characterized by a fast displacement on the endothelium along the direction of flow. Diapedesis of stationary neutrophils was unchanged by the lack of endothelial ICAM-1 and ICAM-2 and occurred exclusively via the paracellular pathway. Crawling neutrophils, although preferentially crossing the BBB through the endothelial junctions, could additionally breach the BBB via the transcellular route. Thus, β2 integrin-mediated neutrophil crawling on endothelial ICAM-1 and ICAM-2 is a prerequisite for transcellular neutrophil diapedesis across the inflamed BBB.

  8. Integrin-mediated tyrosine phosphorylation and cytokine message induction in monocytic cells. A possible signaling role for the Syk tyrosine kinase.

    Science.gov (United States)

    Lin, T H; Rosales, C; Mondal, K; Bolen, J B; Haskill, S; Juliano, R L

    1995-07-07

    Activation of cytoplasmic tyrosine kinases is an important aspect of signal transduction mediated by integrins. In the human monocytic cell line THP-1, either integrin-dependent cell adhesion to fibronectin or ligation of beta 1 integrins with antibodies causes a rapid and intense tyrosine phosphorylation of two sets of proteins of about 65-75 and 120-125 kDa. In addition, integrin ligation leads to nuclear translocation of the p50 and p65 subunits of the NF-kappa B transcription factor, to activation of a reporter gene driven by a promoter containing NF-kappa B sites, and to increased levels of mRNAs for immediate-early genes, including the cytokine interleukin (IL)-1 beta. The tyrosine kinase inhibitors genistein and herbimycin A block both integrin-mediated tyrosine phosphorylation and increases in IL-1 beta message levels, indicating a causal relationship between the two events. The components tyrosine phosphorylated subsequent to cell adhesion include paxillin, pp125FAK, and the SH2 domain containing tyrosine kinase Syk. In contrast, integrin ligation with antibodies induces tyrosine phosphorylation of Syk but not of FAK or paxillin. In adhering cells, pre-treatment with cytochalasin D suppresses tyrosine phosphorylation of FAK and paxillin but not of Syk, while IL-1 beta message induction is unaffected. These observations indicate that the Syk tyrosine kinase may be an important component of an integrin signaling pathway in monocytic cells, leading to activation of NF-kappa B and to increased levels of cytokine messages.

  9. A novel monoclonal antibody to human laminin α5 chain strongly inhibits integrin-mediated cell adhesion and migration on laminins 511 and 521.

    Directory of Open Access Journals (Sweden)

    Zenebech Wondimu

    Full Text Available Laminins, a large family of αβγ heterotrimeric proteins mainly found in basement membranes, are strong promoters of adhesion and migration of multiple cell types, such as tumor and immune cells, via several integrin receptors. Among laminin α (LMα chains, α5 displays the widest tissue distribution in adult life and is synthesized by most cell types. Here, we have generated and characterized five novel monoclonal antibodies (mAbs to the human LMα5 chain to further study the biological relevance of α5 laminins, such as laminins 511 (α5β1γ1 and 521 (α5β2γ1. As detected by ELISA, immunohistochemistry, immunoprecipitation and Western blotting, each antibody displayed unique properties when compared to mAb 4C7, the prototype LMα5 antibody. Of greatest interest, mAb 8G9, but not any other antibody, strongly inhibited α3β1/α6β1 integrin-mediated adhesion and migration of glioma, melanoma, and carcinoma cells on laminin-511 and, together with mAb 4C7, on laminin-521. Accordingly, mAb 8G9 abolished the interaction of soluble α3β1 integrin with immobilized laminins 511 and 521. Binding of mAb 8G9 to laminin-511 was unaffected by the other mAbs to the LMα5 chain but largely hindered by mAb 4E10 to a LMβ1 chain epitope near the globular domain of laminin-511. Thus, mAb 8G9 defines a novel epitope localized at or near the integrin-binding globular domain of the LMα5 chain, which is essential for cell adhesion and migration, and identifies a potential therapeutic target in malignant and inflammatory diseases.

  10. Effects of fluorescent dyes on selectin and integrin-mediated stages of adhesion and migration of flowing leukocytes.

    Science.gov (United States)

    Abbitt, K B; Rainger, G E; Nash, G B

    2000-05-26

    Fluorescent dyes assist visualisation of leukocytes for intravital studies of adhesion or for in vitro studies utilising whole blood. We have used in vitro flow-based assays to investigate the effects of three fluorescent dyes (acridine orange, AO, 5-100 microg/ml; calcein-AM, C-AM, 5-20 microg/ml; rhodamine 6G, R6G, 10-100 microg/ml) on adhesion and migration of isolated neutrophils and mononuclear cells. AO had little effect on the number or velocity of neutrophils rolling on P-selectin presented by a surface coated with platelets. However, AO did cause a dose- and time-dependent conversion of rolling to immobilisation. Pretreatment of neutrophils with an antibody against CD18 prevented this conversion to stationary adhesion, indicating that beta(2) integrins were activated by AO. C-AM had little effect on neutrophil behaviour, but tended to cause some immobilisation at the highest concentration. R6G did not affect the number of neutrophils that bound to the platelet monolayer or the percentage rolling, but the rolling velocity of the neutrophils was increased in a dose-dependent manner. None of the dyes impaired the ability of neutrophils to respond to formyl peptide by converting from rolling to stationary adhesion. Neither C-AM nor R-6G reduced the number of flowing neutrophils or mononuclear cells binding to endothelial cells stimulated with tumour necrosis factor. Interestingly, R-6G inhibited transendothelial migration of mononuclear cells but not neutrophils, while C-AM did not affect transmigration of either cell type. The dose-dependent effects of dyes should be taken into consideration when designing any experimental protocol. AO does not appear to be a suitable dye for adhesion studies. R6G and C-AM can be used at approximately 10 microg/ml (a concentration at which cells can be clearly visualised) although R-6G specifically inhibits the migratory response of mononuclear cells.

  11. Controlling Self-Renewal and Differentiation of Stem Cells via Mechanical Cues

    Directory of Open Access Journals (Sweden)

    Michele M. Nava

    2012-01-01

    Full Text Available The control of stem cell response in vitro, including self-renewal and lineage commitment, has been proved to be directed by mechanical cues, even in the absence of biochemical stimuli. Through integrin-mediated focal adhesions, cells are able to anchor onto the underlying substrate, sense the surrounding microenvironment, and react to its properties. Substrate-cell and cell-cell interactions activate specific mechanotransduction pathways that regulate stem cell fate. Mechanical factors, including substrate stiffness, surface nanotopography, microgeometry, and extracellular forces can all have significant influence on regulating stem cell activities. In this paper, we review all the most recent literature on the effect of purely mechanical cues on stem cell response, and we introduce the concept of “force isotropy” relevant to cytoskeletal forces and relevant to extracellular loads acting on cells, to provide an interpretation of how the effects of insoluble biophysical signals can be used to direct stem cells fate in vitro.

  12. Voltage Controlled Dynamic Demand Response

    DEFF Research Database (Denmark)

    Bhattarai, Bishnu Prasad; Bak-Jensen, Birgitte; Mahat, Pukar

    2013-01-01

    central or dispersed generations might not be sufficient for future scenario. One of the effective methods to cope with this scenario is to enable demand response. This paper proposes a dynamic voltage regulation based demand response technique to be applied in low voltage (LV) distribution feeders....... An adaptive dynamic model has been developed to determine composite voltage dependency of an aggregated load on feeder level. Following the demand dispatch or control signal, optimum voltage setting at the LV substation is determined based on the voltage dependency of the load. Furthermore, a new technique...... has been proposed to estimate the voltage at consumer point of connection (POC) to ensure operation within voltage limits. Finally, the effectiveness of the proposed method is analyzed comprehensively with reference to three different scenarios on a low voltage (LV) feeder (Borup feeder) owned...

  13. The Kindlin 3 Pleckstrin Homology Domain Has an Essential Role in Lymphocyte Function-associated Antigen 1 (LFA-1) Integrin-mediated B Cell Adhesion and Migration

    Science.gov (United States)

    Hart, Rosie; Stanley, Paula; Chakravarty, Probir; Hogg, Nancy

    2013-01-01

    The protein kindlin 3 is mutated in the leukocyte adhesion deficiency III (LAD-III) disorder, leading to widespread infection due to the failure of leukocytes to migrate into infected tissue sites. To gain understanding of how kindlin 3 controls leukocyte function, we have focused on its pleckstrin homology (PH) domain and find that deletion of this domain eliminates the ability of kindlin 3 to participate in adhesion and migration of B cells mediated by the leukocyte integrin lymphocyte function-associated antigen 1 (LFA-1). PH domains are often involved in membrane localization of proteins through binding to phosphoinositides. We show that the kindlin 3 PH domain has binding affinity for phosphoinositide PI(3,4,5)P3 over PI(4,5)P2. It has a major role in membrane association of kindlin 3 that is enhanced by the binding of LFA-1 to intercellular adhesion molecule 1 (ICAM-1). A splice variant, kindlin 3-IPRR, has a four-residue insert in the PH domain at a critical site that influences phosphoinositide binding by enhancing binding to PI(4,5)P2 as well as by binding to PI(3,4,5)P3. However kindlin 3-IPRR is unable to restore the ability of LAD-III B cells to adhere to and migrate on LFA-1 ligand ICAM-1, potentially by altering the dynamics or PI specificity of binding to the membrane. Thus, the correct functioning of the kindlin 3 PH domain is central to the role that kindlin 3 performs in guiding lymphocyte adhesion and motility behavior, which in turn is required for a successful immune response. PMID:23595985

  14. Activation of AKT signaling promotes cell growth and survival in α7β1 integrin-mediated alleviation of muscular dystrophy.

    Science.gov (United States)

    Boppart, Marni D; Burkin, Dean J; Kaufman, Stephen J

    2011-04-01

    Transgenic expression of the α7 integrin can ameliorate muscle pathology in a mouse model of Duchenne muscular dystrophy (mdx/utr(-/-)) and thus can compensate for the loss of dystrophin in diseased mice. In spite of the beneficial effects of the α7 integrin in protecting mice from dystrophy, identification of molecular signaling events responsible for these changes remains to be established. The purpose of this study was to determine a role for signaling in the amelioration of muscular dystrophy by α7 integrin. Activation of PI3K, ILK, AKT, mTOR, p70S6K, BAD, ERK, and p38 was measured in the muscle from wild type (WT), mdx/utr(-/-) and α7BX2-mdx/utr(-/-) mice using in vitro activity assays or phosphospecific antibodies and western blotting. Significant increases in PI3K activity (47%), ILK activity (2.0-fold), mTOR (Ser2448) (57%), p70S6K (Thr389) (11.7-fold), and ERK (Thr202/Tyr204) (66%) were demonstrated in dystrophic mdx/utr(-/-) muscle compared to WT. A significant decrease in p38 phosphorylation (2.9-fold) was also observed. Although most of these signaling events were similar in dystrophic mdx/utr(-/-) mice overexpressing the α7 integrin, the AKT (Ser473):AKT ratio (2-fold vs. WT) and p70S6K phosphorylation (18-fold vs. WT) were higher in α7BX2-mdx/utr(-/-) compared to mdx/utr(-/-) mice. In addition, increased phosphorylation of BAD Serine 112 may contribute to the significant reduction in TUNEL(+) cells observed in α7BX2-mdx/utr(-/-) mice. We conclude that the α7β1 integrin confers a protective effect in dystrophic muscle through the activation of the ILK, AKT, p70S6K and BAD signaling to promote muscle cell survival. Copyright © 2010 Elsevier B.V. All rights reserved.

  15. Mobility of the Arg-Gly-Asp ligand on the outermost surface of biomaterials suppresses integrin-mediated mechanotransduction and subsequent cell functions.

    Science.gov (United States)

    Kakinoki, Sachiro; Seo, Ji-Hun; Inoue, Yuuki; Ishihara, Kazuhiko; Yui, Nobuhiko; Yamaoka, Tetsuji

    2015-02-01

    Mechanotransduction in the regulation of cellular responses has been previously studied using elastic hydrogels. Because cells interact only with the surface of biomaterials, we are focusing on the molecular mobility at the outermost surface of biomaterials. In this study, surfaces with the mobile Arg-Gly-Asp-Ser (RGDS) peptide have been constructed. Cell culture substrates were coated with ABA-type block copolymers composed of poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate) segments (A) and a polyrotaxane (PRX) unit with RGDS bound to α-cyclodextrin (B). Adhesion, morphological changes and actin filament formation of human umbilical vein endothelial cells were reduced on the surfaces containing mobile PRX-RGDS in comparison to the immobile RGDS surfaces constructed from random copolymers with RGDS side groups (Prop-andom-RGDS). In the neurite outgrowth assay using rat adrenal pheochromocytoma cells (PC12), only ∼20% of adherent PC12 cells had neurites on PRX-RGDS surfaces, but more than 50% did on the Random-RGDS surface. The beating colony of dimethyl-sulfoxide-treated mouse embryonic carcinoma cells (P19CL6) were found 10 and 14 days after induction on PRX-RGDS and Random-RGDS surfaces, respectively. After 22 days, the beating colony disappeared on PRX-RGDS surfaces, but many colonies remained on Random-RGDS surfaces. These data suggest that the molecular mobility of the cell-binding ligand on the outermost surface of materials effectively suppresses the actin filament formation and differentiation of these functional cell lines, and may be used as a culture substrate for immature stem cells or progenitor cells. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  16. Alternagin-C, a disintegrin-like protein from the venom of Bothrops alternatus, modulates a2ß1 integrin-mediated cell adhesion, migration and proliferation

    Directory of Open Access Journals (Sweden)

    Selistre-de-Araujo H.S.

    2005-01-01

    Full Text Available The alpha2ß1 integrin is a major collagen receptor that plays an essential role in the adhesion of normal and tumor cells to the extracellular matrix. Alternagin-C (ALT-C, a disintegrin-like protein purified from the venom of the Brazilian snake Bothrops alternatus, competitively interacts with the alpha2ß1 integrin, thereby inhibiting collagen binding. When immobilized in plate wells, ALT-C supports the adhesion of fibroblasts as well as of human vein endothelial cells (HUVEC and does not detach cells previously bound to collagen I. ALT-C is a strong inducer of HUVEC proliferation in vitro. Gene expression analysis was done using an Affimetrix HU-95A probe array with probe sets of ~10,000 human genes. In human fibroblasts growing on collagen-coated plates, ALT-C up-regulates the expression of several growth factors including vascular endothelial growth factor, as well as some cell cycle control genes. Up-regulation of the vascular endothelial growth factor gene and other growth factors could explain the positive effect on HUVEC proliferation. ALT-C also strongly activates protein kinase B phosphorylation, a signaling event involved in endothelial cell survival and angiogenesis. In human neutrophils, ALT-C has a potent chemotactic effect modulated by the intracellular signaling cascade characteristic of integrin-activated pathways. Thus, ALT-C acts as a survival factor, promoting adhesion, migration and endothelial cell proliferation after binding to alpha2ß1 integrin on the cell surface. The biological activities of ALT-C may be helpful as a therapeutic strategy in tissue regeneration as well as in the design of new therapeutic agents targeting alpha2ß1 integrin.

  17. Chronic mild hypoxia promotes profound vascular remodeling in spinal cord blood vessels, preferentially in white matter, via an α5β1 integrin-mediated mechanism.

    Science.gov (United States)

    Halder, Sebok K; Kant, Ravi; Milner, Richard

    2018-01-03

    Spinal cord injury (SCI) leads to rapid destruction of neuronal tissue, resulting in devastating motor and sensory deficits. This is exacerbated by damage to spinal cord blood vessels and loss of vascular integrity. Thus, approaches that protect existing blood vessels or stimulate the growth of new blood vessels might present a novel approach to minimize loss or promote regeneration of spinal cord tissue following SCI. In light of the remarkable power of chronic mild hypoxia (CMH) to stimulate vascular remodeling in the brain, the goal of this study was to examine how CMH (8% O2 for up to 7 days) affects blood vessel remodeling in the spinal cord. We found that CMH promoted the following: (1) endothelial proliferation and increased vascularity as a result of angiogenesis and arteriogenesis, (2) increased vascular expression of the angiogenic extracellular matrix protein fibronectin as well as concomitant increases in endothelial expression of the fibronectin receptor α5β1 integrin, (3) strongly upregulated endothelial expression of the tight junction proteins claudin-5, ZO-1 and occludin and (4) astrocyte activation. Of note, the vascular remodeling changes induced by CMH were more extensive in white matter. Interestingly, hypoxic-induced vascular remodeling in spinal cord blood vessels was markedly attenuated in mice lacking endothelial α5 integrin expression (α5-EC-KO mice). Taken together, these studies demonstrate the considerable remodeling potential of spinal cord blood vessels and highlight an important angiogenic role for the α5β1 integrin in promoting endothelial proliferation. They also imply that stimulation of the α5β1 integrin or controlled use of mild hypoxia might provide new approaches for promoting angiogenesis and improving vascular integrity in spinal cord blood vessels.

  18. Social Responsibility as a Management Control System

    National Research Council Canada - National Science Library

    Barger, Anthony

    2004-01-01

    In this report, the authors examine how businesses with social responsibility as part of their core strategy use related management control systems within the business strategy control model set forth...

  19. Process Control Minitoring by Stress Response

    Energy Technology Data Exchange (ETDEWEB)

    Hazen, Terry C.; Stahl, David A.

    2006-04-17

    Environmental contamination with a variety of pollutants hasprompted the development of effective bioremediation strategies. But howcan these processes be best monitored and controlled? One avenue underinvestigation is the development of stress response systems as tools foreffective and general process control. Although the microbial stressresponse has been the subject of intensive laboratory investigation, theenvironmental reflection of the laboratory response to specific stresseshas been little explored. However, it is only within an environmentalcontext, in which microorganisms are constantly exposed to multiplechanging environmental stresses, that there will be full understanding ofmicrobial adaptive resiliency. Knowledge of the stress response in theenvironment will facilitate the control of bioremediation and otherprocesses mediated by complex microbial communities.

  20. On Control Strategies for Responsive Architectural Structures

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Parigi, Dario

    2012-01-01

    The present paper considers control of responsive architectural structures for improvement of structural performance by recognizing changes in their environments and loads, adapting to meet goals, and using past events to improve future performance or maintain serviceability. The general scope...... of the paper is to discuss control strategies for responsive architectural structures, particularly reconfigurable architectural structures which can transform body shape, i.e. a transformation into more than one or two different shape alternatives....

  1. Wireless Demand Response Controls for HVAC Systems

    Energy Technology Data Exchange (ETDEWEB)

    Federspiel, Clifford

    2009-06-30

    The objectives of this scoping study were to develop and test control software and wireless hardware that could enable closed-loop, zone-temperature-based demand response in buildings that have either pneumatic controls or legacy digital controls that cannot be used as part of a demand response automation system. We designed a SOAP client that is compatible with the Demand Response Automation Server (DRAS) being used by the IOUs in California for their CPP program, design the DR control software, investigated the use of cellular routers for connecting to the DRAS, and tested the wireless DR system with an emulator running a calibrated model of a working building. The results show that the wireless DR system can shed approximately 1.5 Watts per design CFM on the design day in a hot, inland climate in California while keeping temperatures within the limits of ASHRAE Standard 55: Thermal Environmental Conditions for Human Occupancy.

  2. Resurgence: Response competition, stimulus control, and reinforcer control.

    Science.gov (United States)

    Podlesnik, Christopher A; Kelley, Michael E

    2014-09-01

    Resurgence is the relapse of a previously reinforced and then extinguished target response when extinguishing a more recently reinforced alternative response. We designed the present study to assess the contribution of stimulus-control and reinforcer-control processes in determining resurgence. In a modified resurgence procedure, we removed the alternative discriminative stimulus signaling alternative reinforcement when extinguishing the alternative response. This produced more abrupt resurgence of target responding than in a typical resurgence procedure maintaining the alternative discriminative stimulus when extinguishing the alternative response. The overall amount of resurgence did not differ. Importantly, a "renewal" control added and removed the alternative stimulus during extinction, identically as in the modified resurgence procedure. However, alternative responding was never reinforced, which produced no relapse of target responding. Therefore, the more abrupt resurgence with the modified procedure than with the typical procedure suggests removing the alternative stimulus reduced the competition between alternative and target responding. These findings revealed the importance of adding and removing alternative reinforcement in producing resurgence (reinforcer control) but little influence of simply adding and removing the alternative stimulus (stimulus control). These data suggest that clinicians should consider the long-term availability of the alternative response option when developing differential-reinforcement interventions. © Society for the Experimental Analysis of Behavior.

  3. Stimuli responsive nanomaterials for controlled release applications

    KAUST Repository

    Li, Song

    2012-01-01

    The controlled release of therapeutics has been one of the major challenges for scientists and engineers during the past three decades. Coupled with excellent biocompatibility profiles, various nanomaterials have showed great promise for biomedical applications. Stimuli-responsive nanomaterials guarantee the controlled release of cargo to a given location, at a specific time, and with an accurate amount. In this review, we have combined the major stimuli that are currently used to achieve the ultimate goal of controlled and targeted release by "smart" nanomaterials. The most heavily explored strategies include (1) pH, (2) enzymes, (3) redox, (4) magnetic, and (5) light-triggered release.

  4. A Responsive Battery with Controlled Energy Release.

    Science.gov (United States)

    Wang, Xiaopeng; Gao, Jian; Cheng, Zhihua; Chen, Nan; Qu, Liangti

    2016-11-14

    A new type of responsive battery with the fascinating feature of pressure perceptibility has been developed, which can spontaneously, timely and reliably control the power outputs (e.g., current and voltage) in response to pressure changes. The device design is based on the structure of the Zn-air battery, in which graphene-coated sponge serves as pressure-sensitive air cathode that endows the whole system with the capability of self-controlled energy release. The responsive batteries exhibit superior battery performance with high open-circuit voltage (1.3 V), and competitive areal capacity of 1.25 mAh cm -2 . This work presents an important move towards next-generation intelligent energy storage devices with energy management function. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Human response to an individually controlled microenvironment

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor; Knudsen, G.L.

    2007-01-01

    The response of 48 subjects to an individually controlled microenvironment was studied at room air temperatures of 20 degrees C, 22 degrees C, and 26 degrees C An individually controlled system (ICS) comprising personalized ventilation, an under-desk air terminal device supplying cool air, a chair...... with convectively heated backrest, an under-desk radiant heating panel, and a floor-heating panel were used. The temperature of the air supplied from the personalized ventilation and the under-desk device was 20 degrees C The subjects were provided with control of the flow rate and direction of the personalized air...... at a room temperature of 22 degrees C without ICS. Thus, ICS will increase the number of satisfied occupants when applied in practice. The design and control of the ICS, as well as the background air distribution in a room, should be carefully considered in order to obtain the maximum number of occupants...

  6. Human response to an individually controlled environment

    DEFF Research Database (Denmark)

    Knudsen, G.L.; Melikov, Arsen Krikor

    2005-01-01

    Forty-eight subjects tested an individually controlled system (ICS) at room air temperatures of 20, 22 and 26 degrees C. Human response to a reference condition without the ICS at a room air temperature of 22 degrees C was also collected. ne ICS incorporated Personalized Ventilation (PV), an under......-desk air terminal device supplying cool air, a chair with convectively heated backrest, an under-desk radiant heating panel and a floor-heating panel. The temperature of the PV air and the under-desk air was kept at 20 degrees C. The subjects were provided with control of the flow rate and direction...

  7. 21 CFR 211.22 - Responsibilities of quality control unit.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Responsibilities of quality control unit. 211.22... Personnel § 211.22 Responsibilities of quality control unit. (a) There shall be a quality control unit that... have been fully investigated. The quality control unit shall be responsible for approving or rejecting...

  8. Control of the skin scarring response

    Directory of Open Access Journals (Sweden)

    Lydia M. Ferreira

    2009-09-01

    Full Text Available There comes a time when the understanding of the cutaneous healing process becomes essential due to the need for a precocious tissue repair to reduce the physical, social, and psychological morbidity. Advances in the knowledge on the control of interaction among cells, matrix and growth factors will provide more information on the Regenerative Medicine, an emerging area of research in medical bioengineering. However, considering the dynamism and complexity of the cutaneous healing response, it is fundamental to understand the control mechanism exerted by the interaction and synergism of both systems, cutaneous nervous and central nervous, via hypothalamus hypophysis-adrenal axis, a relevant subject, but hardly ever explored. The present study reviews the neuro-immune-endocrine physiology of the skin responsible for its multiple functions and the extreme disturbances of the healing process, like the excess and deficiency of the extracellular matrix deposition.Aproxima-se uma época na qual é fundamental a compreensão do processo cicatricial cutâneo frente à necessidade da restauração tecidual precoce, visando a diminuição das morbidades física, social e psicológica. O avanço no conhecimento acerca do controle das interações entre as células, a matriz e os fatores de crescimento dará maiores informações à Medicina Regenerativa, área de pesquisa emergente da bioengenharia médica. Entretanto, diante do dinamismo e complexidade da resposta cicatricial cutânea torna-se indispensável o entendimento do mecanismo de controle exercido pela interação e sinergismo do sistema nervoso cutâneo e o sistema nervoso central, via eixo hipotálamo-hipófise-adrenal, tema relevante, porém, pouco abordado. O presente estudo revisa a fisiologia neuro-imuno-endócrina da pele, responsável por suas múltiplas funções, e os distúrbios extremos do processocicatricial, como o excesso e deficiência de deposição da matriz extracelular.

  9. Shape Control of Responsive Building Envelopes

    DEFF Research Database (Denmark)

    Foged, Isak Worre; Kirkegaard, Poul Henning; Christensen, Jesper Thøger

    2010-01-01

    alternatives. The adaptive structure is a proposal for a responsive building envelope which is an idea of a first level operational framework for present and future investigations towards performance based responsive architectures through a set of responsive typologies. A mock-up concept of a secondary...

  10. Possible involvement of integrin-mediated signalling in oocyte activation: evidence that a cyclic RGD-containing peptide can stimulate protein kinase C and cortical granule exocytosis in mouse oocytes.

    Science.gov (United States)

    Tatone, Carla; Carbone, Maria Cristina

    2006-09-25

    Mammalian sperm-oocyte interaction at fertilization involves several combined interactions between integrins on the oocyte and integrin ligands (disintegrins) on the sperm. Recent research has indicated the ability of peptides containing the RGD sequence that characterized several sperm disintegrins, to induce intracellular Ca2+ transients and to initiate parthenogenetic development in amphibian and bovine oocytes. In the present study, we investigate the hypothesis that an integrin-associated signalling may participate in oocyte activation signalling by determining the ability of a cyclic RGD-containing peptide to stimulate the activation of protein kinase C (PKC) and the exocytosis of cortical granules in mouse oocytes. An In-Vitro-Fertilization assay (IVF) was carried in order to test the condition under which a peptide containing the RGD sequence, cyclo(Arg-Gly-Asp-D-Phe-Val), was able to inhibit sperm fusion with zona-free mouse oocytes at metaphase II stage. PKC activity was determined by means of an assay based on the ability of cell lysates to phosphorylate MARKS peptide, a specific PKC substrate. Loss of cortical granules was evaluated by measuring density in the oocyte cortex of cortical granules stained with LCA-biotin/Texas red-streptavidin. In all the experiments, effects of a control peptide containing a non RGD sequence, cyclo(Arg-Ala-Asp-D-Phe-Val), were evaluated. The IVF assay revealed that the fusion rate declined significantly when insemination was carried out in the presence of cyclic RGD peptide at concentrations > or = 250 microM (P exocytosis of cortical granules. These data support the view that RGD-binding receptors may function as signalling receptors giving rise integrated signalling not sufficient for a full oocyte activation response. This study may contribute to the understanding of possible negative effects of skipping gamete interaction in IVF techniques.

  11. Possible involvement of integrin-mediated signalling in oocyte activation: evidence that a cyclic RGD-containing peptide can stimulate protein kinase C and cortical granule exocytosis in mouse oocytes

    Directory of Open Access Journals (Sweden)

    Carbone Maria

    2006-09-01

    Full Text Available Abstract Background Mammalian sperm-oocyte interaction at fertilization involves several combined interactions between integrins on the oocyte and integrin ligands (disintegrins on the sperm. Recent research has indicated the ability of peptides containing the RGD sequence that characterized several sperm disintegrins, to induce intracellular Ca2+ transients and to initiate parthenogenetic development in amphibian and bovine oocytes. In the present study, we investigate the hypothesis that an integrin-associated signalling may participate in oocyte activation signalling by determining the ability of a cyclic RGD-containing peptide to stimulate the activation of protein kinase C (PKC and the exocytosis of cortical granules in mouse oocytes. Methods An In-Vitro-Fertilization assay (IVF was carried in order to test the condition under which a peptide containing the RGD sequence, cyclo(Arg-Gly-Asp-D-Phe-Val, was able to inhibit sperm fusion with zona-free mouse oocytes at metaphase II stage. PKC activity was determined by means of an assay based on the ability of cell lysates to phosphorylate MARKS peptide, a specific PKC substrate. Loss of cortical granules was evaluated by measuring density in the oocyte cortex of cortical granules stained with LCA-biotin/Texas red-streptavidin. In all the experiments, effects of a control peptide containing a non RGD sequence, cyclo(Arg-Ala-Asp-D-Phe-Val, were evaluated. Results The IVF assay revealed that the fusion rate declined significantly when insemination was carried out in the presence of cyclic RGD peptide at concentrations > or = 250 microM (P Conclusion The presents results provide evidence that a cyclic RGD peptide highly effective in inhibiting sperm-oocyte interaction stimulates in mouse oocytes the activation of PKC and the exocytosis of cortical granules. These data support the view that RGD-binding receptors may function as signalling receptors giving rise integrated signalling not sufficient for

  12. Rotor Flapping Response to Active Control

    Science.gov (United States)

    Nguyen, Khanh; Johnson, Wayne

    2004-01-01

    Rotor active control using higher harmonic blade pitch has been proposed as a means to reduce both rotor radiated noise and airframe vibration and to enhance rotor performance. The higher harmonic input, however, can affect rotor thrust and cyclic flapping - the basic trim characteristics of the rotor. Some of the trim changes can negate the active control benefits. For example, wind tunnel test results of a full scale BO-105 rotor with individual-blade control indicate some rotor performance improvements, accompanied with changes in rotor trim, using two-per-rev blade pitch input. The observed performance benefits could therefore be a simple manifestation of the trim change rather than an efficient redistribution of the rotor airloads. More recently, the flight test of the BO-105 helicopter equip,ped with individual-blade-control actuators also reported trim changes whenever the two-per-rev blade pitch for noise reduction was activated. The pilot had to adjust the trim control to maintain the aircraft under a constant flight path. These two cases highlight the, importance of trim considerations in the application of active control to rotorcraft.

  13. Demand Response on domestic thermostatically controlled loads

    DEFF Research Database (Denmark)

    Lakshmanan, Venkatachalam

    Electricity has become an inevitable part of human life in present day world. In the past two centuries, the electric power system has undergone a lot of changes. Due to the awareness about the adverse impact of the fossil fuels, the power industry is adopting green and sustainable energy sources....... For a safe and reliable operation of electric power systems, the balance between electricity generation and consumption has to be maintained. The conventional fossil fuel based power generation achieves this balance by adjusting the generation to follow the consumption. In the electric power system...... with renewable energy sources, the production cannot be adjusted to match the demand due to the fluctuating nature of the renewable energy sources. Therefore, the demand has to be adjusted to match the power production. The concept of adjusting the demand to match the production is called demand response...

  14. Reward prospect rapidly speeds up response inhibition via reactive control.

    Science.gov (United States)

    Boehler, Carsten N; Schevernels, Hanne; Hopf, Jens-Max; Stoppel, Christian M; Krebs, Ruth M

    2014-06-01

    Response inhibition is an important cognitive-control function that allows for already-initiated or habitual behavioral responses to be promptly withheld when needed. A typical paradigm to study this function is the stop-signal task. From this task, the stop-signal response time (SSRT) can be derived, which indexes how rapidly an already-initiated response can be canceled. Typically, SSRTs range around 200 ms, identifying response inhibition as a particularly rapid cognitive-control process. Even so, it has recently been shown that SSRTs can be further accelerated if successful response inhibition is rewarded. Since this earlier study effectively ruled out differential preparatory (proactive) control adjustments, the reward benefits likely relied on boosted reactive control. Yet, given how rapidly such control processes would need to be enhanced, alternative explanations circumventing reactive control are important to consider. We addressed this question with an fMRI study by gauging the overlap of the brain networks associated with reward-related and response-inhibition-related processes in a reward-modulated stop-signal task. In line with the view that reactive control can indeed be boosted swiftly by reward availability, we found that the activity in key brain areas related to response inhibition was enhanced for reward-related stop trials. Furthermore, we observed that this beneficial reward effect was triggered by enhanced connectivity between task-unspecific (reward-related) and task-specific (inhibition-related) areas in the medial prefrontal cortex (mPFC). The present data hence suggest that reward information can be translated very rapidly into behavioral benefits (here, within ~200 ms) through enhanced reactive control, underscoring the immediate responsiveness of such control processes to reward availability in general.

  15. Stress Response and Translation Control in Rotavirus Infection

    Directory of Open Access Journals (Sweden)

    Susana López

    2016-06-01

    Full Text Available The general stress and innate immune responses are closely linked and overlap at many levels. The outcomes of these responses serve to reprogram host expression patterns to prevent viral invasions. In turn, viruses counter attack these cell responses to ensure their replication. The mechanisms by which viruses attempt to control host cell responses are as varied as the number of different virus families. One of the most recurrent strategies used by viruses to control the antiviral response of the cell is to hijack the translation machinery of the host, such that viral proteins are preferentially synthesized, while the expression of the stress and antiviral responses of the cell are blocked at the translation level. Here, we will review how rotaviruses, an important agent of acute severe gastroenteritis in children, overcome the stress responses of the cell to establish a productive infectious cycle.

  16. Responsibility for Birth Control: Sex Differences and Personality Correlates.

    Science.gov (United States)

    Jacobs, Keith W.

    A locally-constructed family planning questionnaire and a series of personality instruments were administered to 100 sexually active, unmarried, undergraduate students (60 females, 40 males). Responses to a question of "whose responsibility is it for using birth control measures" showed that 80% of the women and 83% of the men see that…

  17. Optimal Control Strategy for Abnormal Innate Immune Response

    Directory of Open Access Journals (Sweden)

    Jinying Tan

    2015-01-01

    Full Text Available Innate immune response plays an important role in control and clearance of pathogens following viral infection. However, in the majority of virus-infected individuals, the response is insufficient because viruses are known to use different evasion strategies to escape immune response. In this study, we use optimal control theory to investigate how to control the innate immune response. We present an optimal control model based on an ordinary-differential-equation system from a previous study, which investigated the dynamics and regulation of virus-triggered innate immune signaling pathways, and we prove the existence of a solution to the optimal control problem involving antiviral treatment or/and interferon therapy. We conduct numerical experiments to investigate the treatment effects of different control strategies through varying the cost function and control efficiency. The results show that a separate treatment, that is, only inhibiting viral replication (u1(t or enhancing interferon activity (u2(t, has more advantages for controlling viral infection than a mixed treatment, that is, controlling both (u1(t and (u2(t simultaneously, including the smallest cost and operability. These findings would provide new insight for developing effective strategies for treatment of viral infectious diseases.

  18. Design and Implementation of Frequency-responsive Thermostat Control

    DEFF Research Database (Denmark)

    Nyeng, Preben; Østergaard, Jacob; Togeby, Mikael

    2010-01-01

    of experiments are conducted, where the controller is subject to the actual grid frequency as well as designed frequency inputs, such as step inputs. The results demonstrate that frequency-responsive thermostats can indeed provide a wide range of the frequency-responsive ancillary services requested...... studies indicate that this service might as well be provided by demand-side control. In this paper we investigate in detail how thermal energy storage capacity in thermostatically controlled electric loads can be utilised for frequency-responsive control. We use two specific applications as cases for our...... work: Refrigerators and electric space heating. These two cases clearly illustrate the vast diversity of critical parameters like heat capacity, switching cycles, and temperature tolerance. Based on these, we design appropriate control algorithms that bridge the gap, between on the one hand, the unique...

  19. Participation of caveolae in β1 integrin-mediated mechanotransduction

    OpenAIRE

    Radel, Chris; Carlile-Klusacek, MaryEllen; Rizzo, Victor

    2007-01-01

    We previously reported that caveolin-1 is a key component in a β1 integrin-dependent mechanotransduction pathway suggesting that caveolae organelles and integrins are functionally linked in their mechanotransduction properties. Here, we exposed BAEC monolayers to shear stress then isolated caveolae vesicles form the plasma membrane. While little β1 integrin was detected in caveolae derived from cells kept in static culture, shear stress induced β1 integrin transposition to the caveolae. To ev...

  20. Model Predictive Control based on Finite Impulse Response Models

    DEFF Research Database (Denmark)

    Prasath, Guru; Jørgensen, John Bagterp

    2008-01-01

    We develop a regularized l2 finite impulse response (FIR) predictive controller with input and input-rate constraints. Feedback is based on a simple constant output disturbance filter. The performance of the predictive controller in the face of plant-model mismatch is investigated by simulations...

  1. Controlling Electricity Consumption by Forecasting its Response to Varying Prices

    DEFF Research Database (Denmark)

    Corradi, Olivier; Ochsenfeld, Henning Peter; Madsen, Henrik

    2013-01-01

    In a real-time electricity pricing context where consumers are sensitive to varying prices, having the ability to anticipate their response to a price change is valuable. This paper proposes models for the dynamics of such price-response, and shows how these dynamics can be used to control...... electricity consumption using a one-way price signal. Estimation of the price-response is based on data measurable at grid level, removing the need to install sensors and communication devices between each individual consumer and the price-generating entity. An application for price-responsive heating systems...... is studied based on real data, before conducting a control by price experiment using a mixture of real and synthetic data. With the control objective of following a constant consumption reference, peak heating consumption is reduced by nearly 5%, and 11% of the mean daily heating consumption is shifted....

  2. The Case for Intelligent Propulsion Control for Fast Engine Response

    Science.gov (United States)

    Litt, Jonathan S.; Frederick, Dean K.; Guo, Ten-Huei

    2009-01-01

    Damaged aircraft have occasionally had to rely solely on thrust to maneuver as a consequence of losing hydraulic power needed to operate flight control surfaces. The lack of successful landings in these cases inspired research into more effective methods of utilizing propulsion-only control. That research demonstrated that one of the major contributors to the difficulty in landing is the slow response of the engines as compared to using traditional flight control. To address this, research is being conducted into ways of making the engine more responsive under emergency conditions. This can be achieved by relaxing controller limits, adjusting schedules, and/or redesigning the regulators to increase bandwidth. Any of these methods can enable faster response at the potential expense of engine life and increased likelihood of stall. However, an example sensitivity analysis revealed a complex interaction of the limits and the difficulty in predicting the way to achieve the fastest response. The sensitivity analysis was performed on a realistic engine model, and demonstrated that significantly faster engine response can be achieved compared to standard Bill of Material control. However, the example indicates the need for an intelligent approach to controller limit adjustment in order for the potential to be fulfilled.

  3. Regulation of Stress Responses and Translational Control by Coronavirus.

    Science.gov (United States)

    Fung, To Sing; Liao, Ying; Liu, Ding Xiang

    2016-07-04

    Similar to other viruses, coronavirus infection triggers cellular stress responses in infected host cells. The close association of coronavirus replication with the endoplasmic reticulum (ER) results in the ER stress responses, which impose a challenge to the viruses. Viruses, in turn, have come up with various mechanisms to block or subvert these responses. One of the ER stress responses is inhibition of the global protein synthesis to reduce the amount of unfolded proteins inside the ER lumen. Viruses have evolved the capacity to overcome the protein translation shutoff to ensure viral protein production. Here, we review the strategies exploited by coronavirus to modulate cellular stress response pathways. The involvement of coronavirus-induced stress responses and translational control in viral pathogenesis will also be briefly discussed.

  4. Stimuli-Responsive Materials for Controlled Release Applications

    KAUST Repository

    Li, Song

    2015-04-01

    The controlled release of therapeutics has been one of the major challenges for scientists and engineers during the past three decades. To address this outstanding problem, the design and fabrication of stimuli-responsive materials are pursued to guarantee the controlled release of cargo at a specific time and with an accurate amount. Upon applying different stimuli such as light, magnetic field, heat, pH change, enzymes or redox, functional materials change their physicochemical properties through physical transformation or chemical reactions, allowing the release of payload agents on demand. This dissertation studied three stimuli-responsive membrane systems for controlled release from films of macro sizes to microcapsules of nano sizes. The first membrane system is a polymeric composite film which can decrease and sustain diffusion upon light irradiation. The photo-response of membranes is based on the photoreaction of cinnamic derivatives. The second one is composite membrane which can improve diffusion upon heating. The thermo-response of membranes comes from the volume phase transition ability of hydrogels. The third one is microcapsule which can release encapsulated agents upon light irradiation. The photo-response of capsules results from the photoreaction of nitrobenzyl derivatives. The study on these membrane systems reveals that stimuli-responsive release can be achieved by utilizing different functional materials on either macro or micro level. Based on the abundant family of smart materials, designing and fabricating stimuli-responsive systems shall lead to various advanced release processes on demand for biomedical applications.

  5. Mechanotransduction molecules in the plant gravisensory response: amyloplast/statolith membranes contain a beta 1 integrin-like protein

    Science.gov (United States)

    Lynch, T. M.; Lintilhac, P. M.; Domozych, D.

    1998-01-01

    It has been hypothesized that the sedimentation of amyloplasts within root cap cells is the primary event in the plant gravisensory-signal transduction cascade. Statolith sedimentation, with its ability to generate weighty mechanical signals, is a legitimate means for organisms to discriminate the direction of the gravity vector. However, it has been demonstrated that starchless mutants with reduced statolith densities maintain some ability to sense gravity, calling into question the statolith sedimentation hypothesis. Here we report on the presence of a beta 1 integrin-like protein localized inside amyloplasts of tobacco NT-1 suspension culture, callus cells, and whole-root caps. Two different antibodies to the beta 1 integrin, one to the cytoplasmic domain and one to the extracellular domain, localize in the vicinity of the starch grains within amyloplasts of NT-1. Biochemical data reveals a 110-kDa protein immunoprecipitated from membrane fractions of NT-1 suspension culture indicating size homology to known beta 1 integrin in animals. This study provides the first direct evidence for the possibility of integrin-mediated signal transduction in the perception of gravity by higher plants. An integrin-mediated pathway, initiated by starch grain sedimentation within the amyloplast, may provide the signal amplification necessary to explain the gravitropic response in starch-depleted cultivars.

  6. Supervisors' Responses to Subordinate Performance: Effect of Personal-Control Orientation and Situational Control.

    Science.gov (United States)

    Ashkanasy, Neal M.

    1991-01-01

    Presents a study extending a model of leadership response based on attribution theories to include measures of locus of control and situational control. Describes a procedure by which subjects responded to descriptions of subordinate performance. Concludes that supervisors with an external locus of control were less sensitive to subordinate…

  7. A study of helicopter gust response alleviation by automatic control

    Science.gov (United States)

    Saito, S.

    1983-01-01

    Two control schemes designed to alleviate gust-induced vibration are analytically investigated for a helicopter with four articulated blades. One is an individual blade pitch control scheme. The other is an adaptive blade pitch control algorithm based on linear optimal control theory. In both controllers, control inputs to alleviate gust response are superimposed on the conventional control inputs required to maintain the trim condition. A sinusoidal vertical gust model and a step gust model are used. The individual blade pitch control, in this research, is composed of sensors and a pitch control actuator for each blade. Each sensor can detect flapwise (or lead-lag or torsionwise) deflection of the respective blade. The acturator controls the blade pitch angle for gust alleviation. Theoretical calculations to predict the performance of this feedback system have been conducted by means of the harmonic method. The adaptive blade pitch control system is composed of a set of measurements (oscillatory hub forces and moments), an identification system using a Kalman filter, and a control system based on the minimization of the quadratic performance function.

  8. THE COMMUNICATION OF INTERNAL CONTROL SYSTEM WEAKNESSES - NECESSITY AND RESPONSIBILITY

    Directory of Open Access Journals (Sweden)

    Mariana, NEDELCU (BUNEA

    2014-11-01

    Full Text Available In terms of its mission, the control is an inherent part of management, being a specifically human activity, especially useful serving both the management, business partners, public institutions and public. Especially in the last period, amid the economic and financial crisis manifested in recent years, the control has evolved and evolving both by the improvement of organization and management systems and by the response to continuous development of the environment in which it operates. The control activities are an integral part of the management process by which the entity aims to achieve their objectives. The research methodology consists essentially in a literature review and recent regulations in the analyzed field.The objective of this study is to highlight the way in which shall be communicated the deficiencies of internal control systems, to the persons responsible for their governance, inclusively in the banking system.

  9. Transient response characteristics in a biomolecular integral controller.

    Science.gov (United States)

    Sen, Shaunak

    2016-04-01

    The cellular behaviour of perfect adaptation is achieved through the use of an integral control element in the underlying biomolecular circuit. It is generally unclear how integral action affects the important aspect of transient response in these biomolecular systems, especially in light of the fact that it typically deteriorates the transient response in engineering contexts. To address this issue, the authors investigated the transient response in a computational model of a simple biomolecular integral control system involved in bacterial signalling. They find that the transient response can actually speed up as the integral gain parameter increases. On further analysis, they find that the underlying dynamics are composed of slow and fast modes and the speed-up of the transient response is because of the speed-up of the slow-mode dynamics. Finally, they note how an increase in the integral gain parameter also leads to a decrease in the amplitude of the transient response, consistent with the overall improvement in the transient response. These results should be useful in understanding the overall effect of integral action on system dynamics, particularly for biomolecular systems.

  10. Towards Location-Based Access Control in Healthcare Emergency Response

    DEFF Research Database (Denmark)

    Vicente, Carmen Ruiz; Kirkpatrick, Michael; Ghinita, Gabriel

    2009-01-01

    Recent advances in positioning and tracking technologies have led to the emergence of novel location-based applications that allow participants to access information relevant to their spatio-temporal context. Traditional access control models, such as role-based access control (RBAC...... of complex access control decisions based on spatio-temporal relationships among subjects and objects. Furthermore, such relationships change frequently in dynamic environments, requiring efficient mechanisms to monitor and re-evaluate access control decisions. In this position paper, we present a healthcare...... emergency response scenario which highlights the novel challenges that arise when enforcing access control in an environment with moving subjects and objects. To address a realistic application scenario, we consider movement on road networks, and we identify complex access control decisions relevant...

  11. A Substractive Clustering Based Fuzzy Hybrid Reference Control Design for Transient Response Improvement of PID Controller

    Directory of Open Access Journals (Sweden)

    Endra Joelianto

    2009-11-01

    Full Text Available The well known PID controller has inherent limitations in fulfilling simultaneously the conflicting control design objectives. Parameters of the tuned PID controller should trade off the requirement of tracking set-point performances, disturbance rejection and stability robustness. Combination of hybrid reference control (HRC with PID controller results in the transient response performances can be independently achieved without deteriorating the disturbance rejection properties and the stability robustness requirement. This paper proposes a fuzzy based HRC where the membership functions of the fuzzy logic system are obtained by using a substractive clustering technique. The proposed method guarantees the transient response performances satisfaction while preserving the stability robustness of the closed loop system controlled by the PID controller with effective and systematic procedures in designing the fuzzy hybrid reference control system.

  12. Response of maize and cucumber intercrop to soil moisture control ...

    African Journals Online (AJOL)

    GREGO

    2007-03-05

    Mar 5, 2007 ... Response of maize and cucumber intercrop to soil moisture control through irrigation and mulching during the dry season in Nigeria. Josiah M. Ayotamuno1*, K. Zuofa2, Sunday A. Ofori2 and Reginald B. Kogbara1. 1Department of Agricultural and Environmental Engineering, Rivers State University of ...

  13. Responses of Lens esculenta Moench to controlled environmental factors

    NARCIS (Netherlands)

    Saint-Clair, P.M.

    1972-01-01

    Many experiments were undertaken to study the responses of the lentil cultivars 'Large blonde' and 'Anicia' to controlled environmental factors. They covered different aspects of the physiology and the ecology of the crop.

    The orientation experiments (2) involved germination and

  14. Dendritic Cell Immune Responses in HIV-1 Controllers.

    Science.gov (United States)

    Martin-Gayo, Enrique; Yu, Xu G

    2017-02-01

    Robust HIV-1-specific CD8 T cell responses are currently regarded as the main correlate of immune defense in rare individuals who achieve natural, drug-free control of HIV-1; however, the mechanisms that support evolution of such powerful immune responses are not well understood. Dendritic cells (DCs) are specialized innate immune cells critical for immune recognition, immune regulation, and immune induction, but their possible contribution to HIV-1 immune defense in controllers remains ill-defined. Recent studies suggest that myeloid DCs from controllers have improved abilities to recognize HIV-1 through cytoplasmic immune sensors, resulting in more potent, cell-intrinsic type I interferon secretion in response to viral infection. This innate immune response may facilitate DC-mediated induction of highly potent antiviral HIV-1-specific T cells. Moreover, protective HLA class I isotypes restricting HIV-1-specific CD8 T cells may influence DC function through specific interactions with innate myelomonocytic MHC class I receptors from the leukocyte immunoglobulin-like receptor family. Bi-directional interactions between dendritic cells and HIV-1-specific T cells may contribute to natural HIV-1 immune control, highlighting the importance of a fine-tuned interplay between innate and adaptive immune activities for effective antiviral immune defense.

  15. Response Times of Operators in a Control Room

    DEFF Research Database (Denmark)

    Platz, O.; Rasmussen, Jens; Skanborg, Preben Zacho

    A statistical analysis was made of operator response times recorded in the control room of a research reactor during the years 1972-1974. A homogeneity test revealed that the data consist of a mixture of populations. A small but statistically significant difference is found between day and night...

  16. Hierarchical Control Architecture for Demand Response in Smart Grid Scenario

    DEFF Research Database (Denmark)

    Bhattarai, Bishnu Prasad; Bak-Jensen, Birgitte; Mahat, Pukar

    2013-01-01

    , a number of issues, including DR enabling technologies, control strategy, and control architecture, are still under discussion. This paper outlines novel control requirements based on the categorization of existing DR techniques. More specifically, the roles and responsibilities of smart grid actors...... effective tool for optimum asset utilization and to avoid or delay the need for new infrastructure investment. Furthermore, most of the power networks are under the process of reconfiguration to realize the concept of smart grid and are at the transforming stage to support various forms of DR. However...

  17. Patterns of responses to alternative medicines in controlling allergic conjunctivitis

    Directory of Open Access Journals (Sweden)

    Batra Deepak

    1988-01-01

    Full Text Available This analysis identifies the various patterns of the responses of the medicines in controlling allergic conjunctivitis. The mean S Deviation coefficient of variation, correlation matrix and loading of factors are worked out as stated in the tables. In the present case the Eigen values greater than 1.50 are retained. The four factors retained explain 68% of the total variations of the 16 responses. The first factor shows 23.38% of variations in total responses while first two and first three factors show 42.39% and 58.64% respectively. Thus medicine affective in controlling the symptoms are given In the descending order: oxymetazoline and sodium salicylate and Sodium cromoglycate, Oxymetazoline and Disodium CCromoglycate & Sodium Salicylate and disodium Cromoglycate.

  18. Circadian control of antigen-specific T cell responses

    Directory of Open Access Journals (Sweden)

    Nobis CC

    2016-09-01

    Full Text Available Chloé C Nobis,1–3 Nathalie Labrecque,2–4 Nicolas Cermakian1,5–8 1Douglas Mental Health University Institute, 2Maisonneuve-Rosemont Hospital Research Centre, 3Department of Microbiology, Infectious Diseases and Immunology, 4Department of Medicine, University of Montreal, 5Department of Psychiatry, 6Department of Microbiology and Immunology, 7Department of Neurology and Neurosurgery, 8Department of Physiology, McGill University, Montreal, QC, Canada Abstract: The immune system is composed of two arms, the innate and the adaptive immunity. While the innate response constitutes the first line of defense and is not specific for a particular pathogen, the adaptive response is highly specific and allows for long-term memory of the pathogen encounter. T lymphocytes (or T cells are central players in the adaptive immune response. Various aspects of T cell functions vary according to the time of day. Circadian clocks located in most tissues and cell types generate 24-hour rhythms of various physiological processes. These clocks are based on a set of clock genes, and this timing mechanism controls rhythmically the expression of numerous other genes. Clock genes are expressed in cells of the immune system, including T cells. In this review, we provide an overview of the circadian control of the adaptive immune response, with emphasis on T cells, including their development, trafficking, response to antigen, and effector functions. Keywords: circadian clock, adaptive immune response, T lymphocyte, antigen, cytokine, proliferation

  19. A Modular Telerobot Control System for Accident Response

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Robert J.; Shirey, David L.

    1999-07-20

    The Accident Response Mobile Manipulator System (ARMMS) is a teleoperated emergency response vehicle that deploys two hydraulic manipulators, five cameras, and an array of sensors to the scene of an incident. It is operated from a remote base station that can be situated up to four kilometers away from the site. Recently, a modular telerobot control architecture called SMART (Sandia's Modular Architecture for Robotic and Teleoperation) was applied to ARMMS to improve the precision, safety, and operability of the manipulators on board. Using SMART, a prototype manipulator control system was developed in a couple of days, and an integrated working system was demonstrated within a couple of months. New capabilities such as camera teleoperation, autonomous tool changeout and dual manipulator control have been incorporated. The final system incorporates twenty-two separate modules and implements eight different behavior modes. This paper describes the integration of SMART into the ARMMS system.

  20. Direct Torque Control Induction Motor Drive with Improved Flux Response

    Directory of Open Access Journals (Sweden)

    Bhoopendra Singh

    2012-01-01

    Full Text Available Accurate flux estimation and control of stator flux by the flux control loop is the determining factor in effective implementation of DTC algorithm. In this paper a comparison of voltage-model-based flux estimation techniques for flux response improvement is carried out. The effectiveness of these methods is judged on the basis of Root Mean Square Flux Error (RMSFE, Total Harmonic Distortion (THD of stator current, and dynamic flux response. The theoretical aspects of these methods are discussed and a comparative analysis is provided with emphasis on digital signal processor (DSP based controller implementation. The effectiveness of the proposed flux estimation algorithm is investigated through simulation and experimentally validated on a test drive.

  1. Executive control suppresses pupillary responses to aversive stimuli.

    Science.gov (United States)

    Cohen, Noga; Moyal, Natali; Henik, Avishai

    2015-12-01

    Adaptive behavior depends on the ability to effectively regulate emotional responses. Continuous failure in the regulation of emotions can lead to heightened physiological reactions and to various psychopathologies. Recently, several behavioral and neuroimaging studies showed that exertion of executive control modulates emotion. Executive control is a high-order operation involved in goal-directed behavior, especially in the face of distractors or temptations. However, the role of executive control in regulating emotion-related physiological reactions is unknown. Here we show that exercise of executive control modulates reactivity of both the sympathetic and the parasympathetic components of the autonomic nervous system. Specifically, we demonstrate that both pupillary light reflex and pupil dilation for aversive stimuli are attenuated following recruitment of executive control. These findings offer new insights into the very basic mechanisms of emotion processing and regulation, and can lead to novel interventions for people suffering from emotion dysregulation psychopathologies. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Switchable Bioelectrocatalysis Controlled by Dual Stimuli-Responsive Polymeric Interface.

    Science.gov (United States)

    Parlak, Onur; Ashaduzzaman, Md; Kollipara, Suresh B; Tiwari, Ashutosh; Turner, Anthony P F

    2015-11-04

    The engineering of bionanointerfaces using stimuli-responsive polymers offers a new dimension in the design of novel bioelectronic interfaces. The integration of electrode surfaces with stimuli-responsive molecular cues provides a direct control and ability to switch and tune physical and chemical properties of bioelectronic interfaces in various biodevices. Here, we report a dual-responsive biointerface employing a positively responding dual-switchable polymer, poly(NIPAAm-co-DEAEMA)-b-HEAAm, to control and regulate enzyme-based bioelectrocatalysis. The design interface exhibits reversible activation-deactivation of bioelectrocatalytic reactions in response to change in temperature and in pH, which allows manipulation of biomolecular interactions to produce on/off switchable conditions. Using electrochemical measurements, we demonstrate that interfacial bioelectrochemical properties can be tuned over a modest range of temperature (i.e., 20-60 °C) and pH (i.e., pH 4-8) of the medium. The resulting dual-switchable interface may have important implications not only for the design of responsive biocatalysis and on-demand operation of biosensors, but also as an aid to elucidating electron-transport pathways and mechanisms in living organisms by mimicking the dynamic properties of complex biological environments and processes.

  3. The influence of various types of control on anxiety responses

    OpenAIRE

    生和, 秀敏; 横山, 博司

    1988-01-01

    The purpose of this study was to examine the influence of varied types of control on anxiety responses. Fifty-four paired subjects were randomly assigned into the four experimental groups varied in the probabilities of self-administration and desired outcome. These groups were named, respectivly, SELF (N = 9), OTHER (N = 11), OR (N = 10), and AND (N = 11). The subjects were initially asked to state their preferences for the four avoidance conditions by the method of paired comparisons. After ...

  4. Computer model of cardiovascular control system responses to exercise

    Science.gov (United States)

    Croston, R. C.; Rummel, J. A.; Kay, F. J.

    1973-01-01

    Approaches of systems analysis and mathematical modeling together with computer simulation techniques are applied to the cardiovascular system in order to simulate dynamic responses of the system to a range of exercise work loads. A block diagram of the circulatory model is presented, taking into account arterial segments, venous segments, arterio-venous circulation branches, and the heart. A cardiovascular control system model is also discussed together with model test results.

  5. Controlled Optimal Design Program for the Logit Dose Response Model

    Directory of Open Access Journals (Sweden)

    Jiaqiao Hu

    2010-10-01

    Full Text Available The assessment of dose-response is an integral component of the drug development process. Parallel dose-response studies are conducted, customarily, in preclinical and phase 1, 2 clinical trials for this purpose. Practical constraints on dose range, dose levels and dose proportions are intrinsic issues in the design of dose response studies because of drug toxicity, efficacy, FDA regulations, protocol requirements, clinical trial logistics, and marketing issues. We provide a free on-line software package called Controlled Optimal Design 2.0 for generating controlled optimal designs that can incorporate prior information and multiple objectives, and meet multiple practical constraints at the same time. Researchers can either run the web-based design program or download its stand-alone version to construct the desired multiple-objective controlled Bayesian optimal designs. Because researchers often adopt ad-hoc design schemes such as the equal allocation rules without knowing how efficient such designs would be for the design problem, the program also evaluates the efficiency of user-supplied designs.

  6. Prediction and control of neural responses to pulsatile electrical stimulation

    Science.gov (United States)

    Campbell, Luke J.; Sly, David James; O'Leary, Stephen John

    2012-04-01

    This paper aims to predict and control the probability of firing of a neuron in response to pulsatile electrical stimulation of the type delivered by neural prostheses such as the cochlear implant, bionic eye or in deep brain stimulation. Using the cochlear implant as a model, we developed an efficient computational model that predicts the responses of auditory nerve fibers to electrical stimulation and evaluated the model's accuracy by comparing the model output with pooled responses from a group of guinea pig auditory nerve fibers. It was found that the model accurately predicted the changes in neural firing probability over time to constant and variable amplitude electrical pulse trains, including speech-derived signals, delivered at rates up to 889 pulses s-1. A simplified version of the model that did not incorporate adaptation was used to adaptively predict, within its limitations, the pulsatile electrical stimulus required to cause a desired response from neurons up to 250 pulses s-1. Future stimulation strategies for cochlear implants and other neural prostheses may be enhanced using similar models that account for the way that neural responses are altered by previous stimulation.

  7. Genetic and epigenetic control of plant heat responses

    Directory of Open Access Journals (Sweden)

    Junzhong eLiu

    2015-04-01

    Full Text Available Plants have evolved sophisticated genetic and epigenetic regulatory systems to respond quickly to unfavorable environmental conditions such as heat, cold, drought, and pathogen infections. In particular, heat greatly affects plant growth and development, immunity and circadian rhythm, and poses a serious threat to the global food supply. According to temperatures exposing, heat can be usually classified as warm ambient temperature (about 22-27℃, high temperature (27-30℃ and extremely high temperature (37-42℃, also known as heat stress for the model plant Arabidopsis thaliana. The genetic mechanisms of plant responses to heat have been well studied, mainly focusing on elevated ambient temperature-mediated morphological acclimation and acceleration of flowering, modulation of plant immunity and circadian clock by high temperatures, and thermotolerance to heat stress. Recently, great progress has been achieved on epigenetic regulation of heat responses, including DNA methylation, histone modifications, histone variants, ATP-dependent chromatin remodeling, histone chaperones, small RNAs, long non-coding RNAs and other undefined epigenetic mechanisms. These epigenetic modifications regulate the expression of heat-responsive genes and function to prevent heat-related damage. This review focuses on recent progresses regarding the genetic and epigenetic control of heat responses in plants, and pays more attention to the role of the major epigenetic mechanisms in plant heat responses. Further research perspectives are also discussed.

  8. Real Time Optimal Control of Supercapacitor Operation for Frequency Response

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Yusheng; Panwar, Mayank; Mohanpurkar, Manish; Hovsapian, Rob

    2016-07-01

    Supercapacitors are gaining wider applications in power systems due to fast dynamic response. Utilizing supercapacitors by means of power electronics interfaces for power compensation is a proven effective technique. For applications such as requency restoration if the cost of supercapacitors maintenance as well as the energy loss on the power electronics interfaces are addressed. It is infeasible to use traditional optimization control methods to mitigate the impacts of frequent cycling. This paper proposes a Front End Controller (FEC) using Generalized Predictive Control featuring real time receding optimization. The optimization constraints are based on cost and thermal management to enhance to the utilization efficiency of supercapacitors. A rigorous mathematical derivation is conducted and test results acquired from Digital Real Time Simulator are provided to demonstrate effectiveness.

  9. Resilient controls for ordering uncertain prospects change and response

    CERN Document Server

    Pham, Khanh D

    2014-01-01

    Providing readers with a detailed examination of resilient controls in risk-averse decision, this monograph is aimed toward researchers and graduate students in applied mathematics and electrical engineering with a systems-theoretic concentration. This work contains a timely and responsive evaluation of reforms on the use of asymmetry or skewness pertaining to the restrictive family of quadratic costs that have been appeared in various scholarly forums.  Additionally, the book includes a discussion of the current and ongoing efforts in the usage of risk, dynamic game decision optimization and disturbance mitigation techniques with output feedback measurements tailored toward the worst-case scenarios. This work encompasses some of the current changes across uncertainty quantification, stochastic control communities, and the creative efforts that are being made to increase the understanding of resilient controls. Specific considerations are made in this book for the application of decision theory to resilient ...

  10. Brushless DC motor control system responsive to control signals generated by a computer or the like

    Science.gov (United States)

    Packard, Douglas T. (Inventor); Schmitt, Donald E. (Inventor)

    1987-01-01

    A control system for a brushless DC motor responsive to digital control signals is disclosed. The motor includes a multiphase wound stator and a permanent magnet rotor. The rotor is arranged so that each phase winding, when energized from a DC source, will drive the rotor through a predetermined angular position or step. A commutation signal generator responsive to the shaft position provides a commutation signal for each winding. A programmable control signal generator such as a computer or microprocessor produces individual digital control signals for each phase winding. The control signals and commutation signals associated with each winding are applied to an AND gate for that phase winding. Each gate controls a switch connected in series with the associated phase winding and the DC source so that each phase winding is energized only when the commutation signal and the control signal associated with that phase winding are present. The motor shaft may be advanced one step at a time to a desired position by applying a predetermined number of control signals in the proper sequence to the AND gates and the torque generated by the motor may be regulated by applying a separate control signal to each AND gate which is pulse width modulated to control the total time that each switch connects its associated winding to the DC source during each commutation period.

  11. Brushless DC motor control system responsive to control signals generated by a computer or the like

    Science.gov (United States)

    Packard, D. T.

    1985-04-01

    A control system for a brushless DC motor responsive to digital control signals is disclosed. The motor includes a multiphase wound stator and a permanent magnet rotor. The motor is arranged so that each phase winding, when energized from a DC source, will drive the rotor through a predetermined angular position or step. A commutation signal generator responsive to the shaft position provides a commutation signal for each winding. A programmable control signal generator such as a computer or microprocessor produces individual digital control signals for each phase winding. The control signals and commutation signals associated with each winding are applied to an AND gate for that phase winding. Each gate controls a switch connected in series with the associated phase winding and the DC source so that each phase winding is energized only when the commutation signal and the control signal associated with that phase winding are present. The motor shaft may be advanced one step at a time to a desired position by applying a predetermined number of control signals in the proper sequence to the AND gates and the torque generated by the motor be regulated by applying a separate control signal and each AND gate which is pulse width modulated to control the total time that each switch connects its associated winding to the DC source during each commutation period.

  12. Stimuli-Responsive Liposomes for Controlled Drug Delivery

    KAUST Repository

    Li, Wengang

    2014-09-01

    Liposomes are promising drug delivery vesicles due to their biodegradibility, large volume and biocompatibility towards both hydrophilic and hydrophobic drugs. They suffer, however, from poor stability which limits their use in controlled delivery applications. Herein, a novel method was devised for modification of liposomes with small molecules, polymers or nanoparticles to afford stimuli responsive systems that release on demand and stay relatively stable in the absence of the trigger.. This dissertation discusses thermosensitive, pH sensitive, light sensitive and magnetically triggered liposomes that have been prepared for controlled drug delivery application. RAFT polymerization was utilized for the preparation of thermosensitive liposomes (Cholesterol-PNIPAm) and acid-labile liposomes (DOPE-PAA). With low Mw Cholesterol-PNIPAm, the thermosensitive liposomes proved to be effective for controlled release and decreased the cytotoxicity of PNIPAm by eliciting the polymer doses. By crosslinking the DOPE-PAA on liposome surface with acid-labile diamine linkers, DOPE-PAA liposomes were verified to be sensitive at low pH. The effects of polymer structures (linear or hyperbranched) have also been studied for the stability and release properties of liposomes. Finally, a dual-responsive Au@SPIO embedded liposome hybrid (ALHs) was prepared with light-induced “on-and-off” function by photo-thermal process (visible light) and instant release properties triggered by alternating magnetic field, respectively. The ALH system would be further applied into the cellular imaging field as MRI contrast agent.

  13. Controlled Delivery of Human Cells by Temperature Responsive Microcapsules

    Science.gov (United States)

    Mak, W.C.; Olesen, K.; Sivlér, P.; Lee, C.J.; Moreno-Jimenez, I.; Edin, J.; Courtman, D.; Skog, M.; Griffith, M.

    2015-01-01

    Cell therapy is one of the most promising areas within regenerative medicine. However, its full potential is limited by the rapid loss of introduced therapeutic cells before their full effects can be exploited, due in part to anoikis, and in part to the adverse environments often found within the pathologic tissues that the cells have been grafted into. Encapsulation of individual cells has been proposed as a means of increasing cell viability. In this study, we developed a facile, high throughput method for creating temperature responsive microcapsules comprising agarose, gelatin and fibrinogen for delivery and subsequent controlled release of cells. We verified the hypothesis that composite capsules combining agarose and gelatin, which possess different phase transition temperatures from solid to liquid, facilitated the destabilization of the capsules for cell release. Cell encapsulation and controlled release was demonstrated using human fibroblasts as model cells, as well as a therapeutically relevant cell line—human umbilical vein endothelial cells (HUVECs). While such temperature responsive cell microcapsules promise effective, controlled release of potential therapeutic cells at physiological temperatures, further work will be needed to augment the composition of the microcapsules and optimize the numbers of cells per capsule prior to clinical evaluation. PMID:26096147

  14. Controlled Delivery of Human Cells by Temperature Responsive Microcapsules

    Directory of Open Access Journals (Sweden)

    W.C. Mak

    2015-06-01

    Full Text Available Cell therapy is one of the most promising areas within regenerative medicine. However, its full potential is limited by the rapid loss of introduced therapeutic cells before their full effects can be exploited, due in part to anoikis, and in part to the adverse environments often found within the pathologic tissues that the cells have been grafted into. Encapsulation of individual cells has been proposed as a means of increasing cell viability. In this study, we developed a facile, high throughput method for creating temperature responsive microcapsules comprising agarose, gelatin and fibrinogen for delivery and subsequent controlled release of cells. We verified the hypothesis that composite capsules combining agarose and gelatin, which possess different phase transition temperatures from solid to liquid, facilitated the destabilization of the capsules for cell release. Cell encapsulation and controlled release was demonstrated using human fibroblasts as model cells, as well as a therapeutically relevant cell line—human umbilical vein endothelial cells (HUVECs. While such temperature responsive cell microcapsules promise effective, controlled release of potential therapeutic cells at physiological temperatures, further work will be needed to augment the composition of the microcapsules and optimize the numbers of cells per capsule prior to clinical evaluation.

  15. Electrochemically responsive heterogeneous catalysis for controlling reaction kinetics.

    Science.gov (United States)

    Mao, Xianwen; Tian, Wenda; Wu, Jie; Rutledge, Gregory C; Hatton, T Alan

    2015-01-28

    We report a method to control reaction kinetics using electrochemically responsive heterogeneous catalysis (ERHC). An ERHC system should possess a hybrid structure composed of an electron-conducting porous framework coated with redox-switchable catalysts. In contrast to other types of responsive catalysis, ERHC combines all the following desired characteristics for a catalysis control strategy: continuous variation of reaction rates as a function of the magnitude of external stimulus, easy integration into fixed-bed flow reactors, and precise spatial and temporal control of the catalyst activity. Herein we first demonstrate a facile approach to fabricating a model ERHC system that consists of carbon microfibers with conformal redox polymer coating. Second, using a Michael reaction whose kinetics depends on the redox state of the redox polymer catalyst, we show that use of different electrochemical potentials permits continuous adjustment of the reaction rates. The dependence of the reaction rate on the electrochemical potential generally agrees with the Nernstian prediction, with minor discrepancies due to the multilayer nature of the polymer film. Additionally, we show that the ERHC system can be employed to manipulate the shape of the reactant concentration-time profile in a batch reactor through applying customized potential-time programs. Furthermore, we perform COMSOL simulation for an ERHC-integrated flow reactor, demonstrating highly flexible manipulation of reactant concentrations as a function of both location and time.

  16. Maturation of cognitive control: delineating response inhibition and interference suppression.

    Directory of Open Access Journals (Sweden)

    Christopher R Brydges

    Full Text Available Cognitive control is integral to the ability to attend to a relevant task whilst suppressing distracting information or inhibiting prepotent responses. The current study examined the development of these two subprocesses by examining electrophysiological indices elicited during each process. Thirteen 18 year-old adults and thirteen children aged 8-11 years (mean=9.77 years completed a hybrid Go/Nogo flanker task while continuous EEG data were recorded. The N2 topography for both response inhibition and interference suppression changed with increasing age. The neural activation associated with response inhibition became increasingly frontally distributed with age, and showed decreases of both amplitude and peak latency from childhood to adulthood, possibly due to reduced cognitive demands and myelination respectively occurring during this period. Interestingly, a significant N2 effect was apparent in adults, but not observed in children during trials requiring interference suppression. This could be due to more diffuse activation in children, which would require smaller levels of activation over a larger region of the brain than is reported in adults. Overall, these results provide evidence of distinct maturational processes occurring throughout late childhood and adolescence, highlighting the separability of response inhibition and interference suppression.

  17. Genes Acting on Transcriptional Control during Abiotic Stress Responses

    Directory of Open Access Journals (Sweden)

    Glacy Jaqueline da Silva

    2014-01-01

    Full Text Available Abiotic stresses are the major cause of yield loss in crops around the world. Greater genetic gains are possible by combining the classical genetic improvement with advanced molecular biology techniques. The understanding of mechanisms triggered by plants to meet conditions of stress is of fundamental importance for the elucidation of these processes. Current genetically modified crops help to mitigate the effects of these stresses, increasing genetic gains in order to supply the agricultural market and the demand for better quality food throughout the world. To obtain safe genetic modified organisms for planting and consumption, a thorough grasp of the routes and genes that act in response to these stresses is necessary. This work was developed in order to collect important information about essential TF gene families for transcriptional control under abiotic stress responses.

  18. Human regulatory B cells control the TFH cell response.

    Science.gov (United States)

    Achour, Achouak; Simon, Quentin; Mohr, Audrey; Séité, Jean-François; Youinou, Pierre; Bendaoud, Boutahar; Ghedira, Ibtissem; Pers, Jacques-Olivier; Jamin, Christophe

    2017-07-01

    Follicular helper T (TFH) cells support terminal B-cell differentiation. Human regulatory B (Breg) cells modulate cellular responses, but their control of TFH cell-dependent humoral immune responses is unknown. We sought to assess the role of Breg cells on TFH cell development and function. Human T cells were polyclonally stimulated in the presence of IL-12 and IL-21 to generate TFH cells. They were cocultured with B cells to induce their terminal differentiation. Breg cells were included in these cultures, and their effects were evaluated by using flow cytometry and ELISA. B-cell lymphoma 6, IL-21, inducible costimulator, CXCR5, and programmed cell death protein 1 (PD-1) expressions increased on stimulated human T cells, characterizing TFH cell maturation. In cocultures they differentiated B cells into CD138(+) plasma and IgD(-)CD27(+) memory cells and triggered immunoglobulin secretions. Breg cells obtained by Toll-like receptor 9 and CD40 activation of B cells prevented TFH cell development. Added to TFH cell and B-cell cocultures, they inhibited B-cell differentiation, impeded immunoglobulin secretions, and expanded Foxp3(+)CXCR5(+)PD-1(+) follicular regulatory T cells. Breg cells modulated IL-21 receptor expressions on TFH cells and B cells, and their suppressive activities involved CD40, CD80, CD86, and intercellular adhesion molecule interactions and required production of IL-10 and TGF-β. Human Breg cells control TFH cell maturation, expand follicular regulatory T cells, and inhibit the TFH cell-mediated antibody secretion. These novel observations demonstrate a role for the Breg cell in germinal center reactions and suggest that deficient activities might impair the TFH cell-dependent control of humoral immunity and might lead to the development of aberrant autoimmune responses. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  19. Augmenting Plant Immune Responses and Biological Control by Microbial Determinants

    Directory of Open Access Journals (Sweden)

    Sang Moo Lee

    2015-09-01

    Full Text Available Plant have developed sophisticated defence mechanisms against microbial pathogens. The recent accumulated information allow us to understand the nature of plant immune responses followed by recognition of microbial factors/determinants through cutting-edge genomics and multi-omics techniques. However, the practical approaches to sustain plant health using enhancement of plant immunity is yet to be fully appreciated. Here, we overviewed the general concept and representative examples on the plant immunity. The fungal, bacterial, and viral determinants that was previously reported as the triggers of plant immune responses are introduced and described as the potential protocol of biological control. Specifically, the role of chitin, glucan, lipopolysaccharides/extracellular polysaccharides, microbe/pathogen-associated molecular pattern, antibiotics, mimic-phytohormones, N-acyl homoserine lactone, harpin, vitamins, and volatile organic compounds are considered. We hope that this review stimulates scientific community and farmers to broaden their knowledge on the microbial determinant-based biological control and to apply the technology on the integrated pest management program.

  20. Powdery Mildew Control and Yield Response of Inodorus Melon

    Directory of Open Access Journals (Sweden)

    Ippolito Camele

    Full Text Available The research was carried out on melon (Cucumis melo L. var. inodorus Naud. in 2006 and 2007 at “Pantanello” Experimental Farm (40° 24’N; 16° 48’E; 10 m a.s.l.; Metaponto, southern Italy to evaluate the efficacy of a low environmental impact control strategy against powdery mildew of cucurbits. Winter melon was treated with a new anti-oidium formulation, called Stifénia, obtained from fenugreek seeds and stimulating the plant self-defence. The adopted experimental design included two control strategies (1. biological, using Stifénia and 2. conventional, using penconazole, myclobutanil and sulphur and an untreated control (treated with water alone applied to two cultivars of inodorus melon (cv ‘Amarillo’ and HF1 ‘Cocorito’, the latter a genotype resistant to powdery mildew. Stifénia applications were not effective against the disease; in fact, there were no differences in percentage of attacked plant surface between treated plots and untreated ones. The melon marketable yield was significantly higher with the conventional strategy respect to Stifénia and control. Repeated applications of Stifénia resulted in a significant decrease of marketable yield even in comparison with the untreated control. The cultivars significantly affected powdery mildew development, since the resistant one (‘Cocorito’ was attacked later and damaged always lower than the non-resistant genotype (‘Amarillo’. Laboratory analyses carried out on infected leaves always confirmed that Golovinomyces cichoracearum D.C. was responsible of the disease.

  1. Energy consumption and control response evaluations of AODV routing in WSANs for building-temperature control.

    Science.gov (United States)

    Booranawong, Apidet; Teerapabkajorndet, Wiklom; Limsakul, Chusak

    2013-06-27

    The main objective of this paper is to investigate the effects of routing protocols on wireless sensor and actuator networks (WSANs), focusing on the control system response and the energy consumption of nodes in a network. We demonstrate that routing algorithms designed without considering the relationship between communication and control cannot be appropriately used in wireless networked control applications. For this purpose, an ad-hoc on-demand distance vector (AODV) routing, an IEEE 802.15.4, and a building-temperature control system are employed for this exploration. The findings from our scenarios show that the AODV routing can select a path with a high traffic load for data transmission. It takes a long time before deciding to change a new route although it experiences the unsuccessful transmission of packets. As a result, the desirable control target cannot be achieved in time, and nodes consume more energy due to frequent packet collisions and retransmissions. Consequently, we propose a simple routing solution to alleviate these research problems by modifying the original AODV routing protocol. The delay-threshold is considered to avoid any congested connection during routing procedures. The simulation results demonstrate that our solution can be appropriately applied in WSANs. Both the energy consumption and the control system response are improved.

  2. Energy Consumption and Control Response Evaluations of AODV Routing in WSANs for Building-Temperature Control

    Directory of Open Access Journals (Sweden)

    Chusak Limsakul

    2013-06-01

    Full Text Available The main objective of this paper is to investigate the effects of routing protocols on wireless sensor and actuator networks (WSANs, focusing on the control system response and the energy consumption of nodes in a network. We demonstrate that routing algorithms designed without considering the relationship between communication and control cannot be appropriately used in wireless networked control applications. For this purpose, an ad-hoc on-demand distance vector (AODV routing, an IEEE 802.15.4, and a building-temperature control system are employed for this exploration. The findings from our scenarios show that the AODV routing can select a path with a high traffic load for data transmission. It takes a long time before deciding to change a new route although it experiences the unsuccessful transmission of packets. As a result, the desirable control target cannot be achieved in time, and nodes consume more energy due to frequent packet collisions and retransmissions. Consequently, we propose a simple routing solution to alleviate these research problems by modifying the original AODV routing protocol. The delay-threshold is considered to avoid any congested connection during routing procedures. The simulation results demonstrate that our solution can be appropriately applied in WSANs. Both the energy consumption and the control system response are improved.

  3. Controlling rotordynamic response without squeeze-film dampers (SFDs)

    Science.gov (United States)

    Jiffri, S.; Garvey, S.

    2009-08-01

    SFDs are widely used in rotating machinery to provide damping in order to control rotordynamic response. Although popular, under certain conditions SFDs pose problems such as causing non-synchronous vibration arising from unbalance forces interacting with fluid-film forces affected by cavitation. Furthermore, in the interests of moving towards oil-free rotating machines, the need arises to find alternative means of rotordynamic response control. In choosing a new vibration control technology, it is first necessary to consider certain general, configuration-independent criteria. For example, does the actuation method provide a limited stroke (eg. piezoelectric or giant magnetostrictive) or is the stroke a "motorised" solution (eg. an ultrasonic motor directly driving the actuator or a pump acting to vary the fill level of closed deformable volumes with incompressible fluid) Is the work per stroke per unit mass of the actuator material sufficient to provide the maximum stroke and force required for the control? What is the bandwidth of the actuator? In the case of electromechanical actuation, what is the coupling factor? Can the elements of the actuator withstand the high temperatures of the operating environment? Is the solution an active or passive one? What are the fatigue properties of the materials used in the actuator? These are some of the questions that need to be considered when evaluating a new control method. Once the significant properties have been identified, it is necessary to consider each of these in the context of the intended application. If one considers the actuation type, in the limited stroke case it will be required for the actuation to take place at synchronous frequency and the work per stroke per unit mass will determine the quantity of material required. For some applications - particularly aero-engines - one seeks to minimise overall mass and therefore materials with high values of work per stroke per unit mass are attractive. By contrast

  4. Block factorization of step response model predictive control problems

    DEFF Research Database (Denmark)

    Kufoalor, D. K.M.; Frison, Gianluca; Imsland, L.

    2017-01-01

    in a traditional manner and use the computationally efficient block factorization facilities in QP solution methods. In order to solve the MPC problem efficiently, both tailored Riccati recursion and condensing algorithms are proposed and embedded into an interior-point method. The proposed algorithms were...... implemented in the HPMPC framework, and the performance is evaluated through simulation studies. The results confirm that a computationally fast controller is achieved, compared to the traditional step response MPC scheme that relies on an explicit prediction formulation. Moreover, the tailored condensing...... algorithm exhibits superior performance and produces solution times comparable to that achieved when using a condensing scheme for an equivalent (but much smaller) state-space model derived from first-principles. Implementation aspects necessary for high performance on embedded platforms are discussed...

  5. The Unfolded Protein Response and Cell Fate Control.

    Science.gov (United States)

    Hetz, Claudio; Papa, Feroz R

    2017-10-25

    The secretory capacity of a cell is constantly challenged by physiological demands and pathological perturbations. To adjust and match the protein-folding capacity of the endoplasmic reticulum (ER) to changing secretory needs, cells employ a dynamic intracellular signaling pathway known as the unfolded protein response (UPR). Homeostatic activation of the UPR enforces adaptive programs that modulate and augment key aspects of the entire secretory pathway, whereas maladaptive UPR outputs trigger apoptosis. Here, we discuss recent advances into how the UPR integrates information about the intensity and duration of ER stress stimuli in order to control cell fate. These findings are timely and significant because they inform an evolving mechanistic understanding of a wide variety of human diseases, including diabetes mellitus, neurodegeneration, and cancer, thus opening up the potential for new therapeutic modalities to treat these diverse diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. The response of anosteocytic bone to controlled loading.

    Science.gov (United States)

    Atkins, Ayelet; Milgram, Joshua; Weiner, Steve; Shahar, Ron

    2015-11-01

    The bones of the skeleton of most advanced teleost fish do not contain osteocytes. Considering the pivotal role assigned to osteocytes in the process of modeling and remodeling (the adaptation of external and internal bone structure and morphology to external loads and the repair of areas with micro-damage accumulation, respectively) it is unclear how, and even whether, their skeleton can undergo modeling and remodeling. Here, we report on the results of a study of controlled loading of the anosteocytic opercula of tilapia (Oreochromis aureus). Using a variety of microscopy techniques we show that the bone of the anosteocytic tilapia actively adapts to applied loads, despite the complete absence of osteocytes. We show that in the directly loaded area, the response involves a combination of bone resorption and bone deposition; we interpret these results and the structure of the resultant bone tissue to mean that both modeling and remodeling are taking place in response to load. We further show that adjacent to the loaded area, new bone is deposited in an organized, layered manner, typical of a modeling process. The material stiffness of the newly deposited bone is higher than that of the bone which was present prior to loading. The absence of osteocytes requires another candidate cell for mechanosensing and coordinating the modeling process, with osteoblasts seeming the most likely candidates. © 2015. Published by The Company of Biologists Ltd.

  7. [Metabolic response to stress, can we control it?].

    Science.gov (United States)

    Longarela, A; Olarra, J; Suárez, L; García de Lorenzo, A

    2000-01-01

    When faced by an external aggression such as shock, sepsis, burns or surgery, the body develops a response, known as stress, comprising hypermetabolism and hypercatabolism related to an alteration in tissue sensitivity to insulin. This alteration seems to be rooted in the transmembrane protein GLUT-4 which takes care of the cell uptake of glucose in skeletal muscle. As a result, there are alterations in the metabolism of carbohydrates, fats and proteins (reduction of immunoglobulins). In the case of surgery, it has been shown that, on the one hand, factors such as rest, pre-operative fasting or the release of inflammatory response factors constrain an even greater alteration in the sensitivity to insulin; and on the other hand that the degree of resistance to insulin depends on the magnitude of the surgery, its duration, bleeding, or on hypothermia and extracorporeal circulation in the case of heart surgery. These metabolic alterations may lead to an increase in the number of infections, mean stay in hospital, and even lead to diabetes mellitus in the long term. Over the last few years, all of this has led several researchers to try to minimize the stress response associated with planned surgery through replacing pre-operative fasting by the administration of carbohydrates, whether or not in association with insulin in perfusion. Beneficial results have been described: control of hyperglycaemia, lower consumption of neoglycogenic amino acids and less alteration of plasma immunity (interleukins, TNF). Future studies will evaluate the influence of these measures on plasma immunity, mean hospital stay and morbidity/mortality.

  8. Modeling, Analysis, and Control of Demand Response Resources

    Energy Technology Data Exchange (ETDEWEB)

    Mathieu, Johanna L. [Univ. of California, Berkeley, CA (United States)

    2012-05-01

    While the traditional goal of an electric power system has been to control supply to fulfill demand, the demand-side can plan an active role in power systems via Demand Response (DR), defined by the Department of Energy (DOE) as “a tariff or program established to motivate changes in electric use by end-use customers in response to changes in the price of electricity over time, or to give incentive payments designed to induce lower electricity use at times of high market prices or when grid reliability is jeopardized” [29]. DR can provide a variety of benefits including reducing peak electric loads when the power system is stressed and fast timescale energy balancing. Therefore, DR can improve grid reliability and reduce wholesale energy prices and their volatility. This dissertation focuses on analyzing both recent and emerging DR paradigms. Recent DR programs have focused on peak load reduction in commercial buildings and industrial facilities (C&I facilities). We present methods for using 15-minute-interval electric load data, commonly available from C&I facilities, to help building managers understand building energy consumption and ‘ask the right questions’ to discover opportunities for DR. Additionally, we present a regression-based model of whole building electric load, i.e., a baseline model, which allows us to quantify DR performance. We use this baseline model to understand the performance of 38 C&I facilities participating in an automated dynamic pricing DR program in California. In this program, facilities are expected to exhibit the same response each DR event. We find that baseline model error makes it difficult to precisely quantify changes in electricity consumption and understand if C&I facilities exhibit event-to-event variability in their response to DR signals. Therefore, we present a method to compute baseline model error and a metric to determine how much observed DR variability results from baseline model error rather than real

  9. Balancing the dual responsibilities of business unit controllers: field and survey evidence

    NARCIS (Netherlands)

    Maas, V.S.; Matejka, M.

    2009-01-01

    We examine how business unit (BU) controllers balance their dual roles of providing information for both local decision-making (local responsibility) and corporate control (functional responsibility). The existing literature suggests that organizations can improve the quality of financial reporting

  10. Does the Environment Responsibility Affect the Management Control System?

    Directory of Open Access Journals (Sweden)

    Hichem DKHILI

    2013-06-01

    Full Text Available The literature suggests a problem emerging between management controls systems with the new responsibilities that companies must take into consideration. This study examines a system design management control tool orientation as behaviors that can overcome the uncertainties related to the environment and register the company in a voluntary approach which takes into account the environmental dimensions. A questionnaire survey sent to 306 Tunisian industrial companies was conducted. The results of the exploratory and confirmatory analysis are required. The results of the principal component factor analysis evidenced by Cronbach's alpha and KMO test, helped to cleanse the items selected from the literature. Similarly, the results of structural equations with indices of structural adjustment and parcimonies have devoted a good quality adjustment. Overall, findings suggest that most of the firm’s environment is uncertain, more tools to include in its environmental dimensions. On the other hand, the voluntary integration of an environmental approach is part of a strategy of cost leadership in the Tunisian industrial companies.

  11. Size-controlled and redox-responsive supramolecular nanoparticles

    Directory of Open Access Journals (Sweden)

    Raquel Mejia-Ariza

    2015-12-01

    Full Text Available Control over the assembly and disassembly of nanoparticles is pivotal for their use as drug delivery vehicles. Here, we aim to form supramolecular nanoparticles (SNPs by combining advantages of the reversible assembly properties of SNPs using host–guest interactions and of a stimulus-responsive moiety. The SNPs are composed of a core of positively charged poly(ethylene imine grafted with β-cyclodextrin (CD and a positively charged ferrocene (Fc-terminated poly(amidoamine dendrimer, with a monovalent stabilizer at the surface. Fc was chosen for its loss of CD-binding properties when oxidizing it to the ferrocenium cation. The ionic strength was shown to play an important role in controlling the aggregate growth. The attractive supramolecular and repulsive electrostatic interactions constitute a balance of forces in this system at low ionic strengths. At higher ionic strengths, the increased charge screening led to a loss of electrostatic repulsion and therefore to faster aggregate growth. A Job plot showed that a 1:1 stoichiometry of host and guest moieties gave the most efficient aggregate growth. Different stabilizers were used to find the optimal stopper to limit the growth. A weaker guest moiety was shown to be less efficient in stabilizing the SNPs. Also steric repulsion is important for achieving SNP stability. SNPs of controlled particle size and good stability (up to seven days were prepared by fine-tuning the ratio of multivalent and monovalent interactions. Finally, reversibility of the SNPs was confirmed by oxidizing the Fc guest moieties in the core of the SNPs.

  12. Vena Cava Responsiveness to Controlled Isovolumetric Respiratory Efforts.

    Science.gov (United States)

    Folino, Anna; Benzo, Marco; Pasquero, Paolo; Laguzzi, Andrea; Mesin, Luca; Messere, Alessandro; Porta, Massimo; Roatta, Silvestro

    2017-10-01

    Respirophasic variation of inferior vena cava (IVC) size is affected by large variability with spontaneous breathing. This study aims at characterizing the dependence of IVC size on controlled changes in intrathoracic pressure. Ten healthy subjects, in supine position, performed controlled isovolumetric respiratory efforts at functional residual capacity, attaining positive (5, 10, and 15 mmHg) and negative (-5, -10, and -15 mmHg) alveolar pressure levels. The isovolumetric constraint implies that equivalent changes are exhibited by alveolar and intrathoracic pressures during respiratory tasks. The IVC cross-sectional area equal to 2.88 ± 0.43 cm 2 at baseline (alveolar pressure = 0 mmHg) was progressively decreased by both expiratory and inspiratory efforts of increasing strength, with diaphragmatic efforts producing larger effects than thoracic ones: -55 ± 15% decrease, at +15 mmHg of alveolar pressure (P < .01), -80 ± 33 ± 12% at -15 mmHg diaphragmatic (P < .01), -33 ± 12% at -15 mmHg thoracic. Significant IVC changes in size (P < .01) and pulsatility (P < .05), along with non significant reduction in the response to respiratory efforts, were also observed during the first 30 minutes of supine rest, detecting an increase in vascular filling, and taking place after switching from the standing to the supine position. This study quantified the dependence of the IVC cross-sectional area on controlled intrathoracic pressure changes and evidenced the stronger influence of diaphragmatic over thoracic activity. Individual variability in thoracic/diaphragmatic respiratory pattern should be considered in the interpretation of the respirophasic modulations of IVC size. © 2017 by the American Institute of Ultrasound in Medicine.

  13. Investigating the Decision Heuristics of Candidate Teachers Who Are Different in Their Responsibility Controls

    Science.gov (United States)

    Özen, Yener

    2016-01-01

    In this study, decision heuristics used by individuals with different responsibility controls were investigated. In the research, 370 final grade university students studying at Erzincan University Faculty of Education were included. In order to collect data, Internally Controlled Responsibility-Externally Controlled Responsibility Scale of Özen…

  14. 14 CFR 121.533 - Responsibility for operational control: Domestic operations.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Responsibility for operational control... § 121.533 Responsibility for operational control: Domestic operations. (a) Each certificate holder conducting domestic operations is responsible for operational control. (b) The pilot in command and the...

  15. 14 CFR 121.535 - Responsibility for operational control: Flag operations.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Responsibility for operational control... § 121.535 Responsibility for operational control: Flag operations. (a) Each certificate holder conducting flag operations is responsible for operational control. (b) The pilot in command and the aircraft...

  16. Adaptive Control of Response Preparedness in Task Switching

    Science.gov (United States)

    Steinhauser, Marco; Hubner, Ronald; Druey, Michel

    2009-01-01

    When rapidly switching between two tasks, bivalent stimuli can accidentally trigger the previously executed and therefore still activated response. Recently, it has been suggested that behavioral response-repetition effects reflect response inhibition that reduces the risk of such erroneous response repetitions. The present study investigated…

  17. Inhibition and impulsivity: behavioral and neural basis of response control.

    Science.gov (United States)

    Bari, Andrea; Robbins, Trevor W

    2013-09-01

    In many circumstances alternative courses of action and thoughts have to be inhibited to allow the emergence of goal-directed behavior. However, this has not been the accepted view in the past and only recently has inhibition earned its own place in the neurosciences as a fundamental cognitive function. In this review we first introduce the concept of inhibition from early psychological speculations based on philosophical theories of the human mind. The broad construct of inhibition is then reduced to its most readily observable component which necessarily is its behavioral manifestation. The study of 'response inhibition' has the advantage of dealing with a relatively simple and straightforward process, the overriding of a planned or already initiated action. Deficient inhibitory processes profoundly affect everyday life, causing impulsive conduct which is generally detrimental for the individual. Impulsivity has been consistently linked to several types of addiction, attention deficit/hyperactivity disorder, mania and other psychiatric conditions. Our discussion of the behavioral assessment of impulsivity will focus on objective laboratory tasks of response inhibition that have been implemented in parallel for humans and other species with relatively few qualitative differences. The translational potential of these measures has greatly improved our knowledge of the neurobiological basis of behavioral inhibition and impulsivity. We will then review the current models of behavioral inhibition along with their expression via underlying brain regions, including those involved in the activation of the brain's emergency 'brake' operation, those engaged in more controlled and sustained inhibitory processes and other ancillary executive functions. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Phytochrome-mediated responses implications for controlled environment research facilities

    Energy Technology Data Exchange (ETDEWEB)

    Smith, H. [Univ. of Leicester (United Kingdom)

    1994-12-31

    Light is undoubtedly the most important environmental variable for plant growth and development; plants not only use radiant energy in photosynthesis, they also respond to the quantity, quality, direction and timing of incident radiation through photomorphogenic responses that can have huge effects on the rate of growth and the pattern of development. It is surprising, therefore, that the manufacturers and suppliers of controlled environment facilities have been singularly uninventive in the design of the lighting assemblies they provide. The consumer has one choice only - a lighting assembly that provides irradiance levels usually only a fraction of sunlight, and a control system that is limited to regulating the timing of the on-off switch. The reasons for these limitations are partly technological, but in the main they result from ignorance on the part of both the consumer and the manufacturer. A specific and powerful example of this ignorance relates to the importance of the so-called far-red wavelengths (FR = 700-800 nm). Because the human eye can hardly detect wavelengths above 700 nm, and photosynthesis also cuts off at ca. 700 mn, the majority of plant and crop physiologists are still almost completely unaware that FR radiation can have massive effects on growth rate and development. In consequence, most growth cabinets have light sources based on fluorescent tubes, and provide very little FR apart from that emitted by a token number of small incandescent bulbs. Larger growth facilities often use broader spectrum light sources, but growth facilities that provide the capability to vary the FR incident upon the plants are about as abundant as seals in the Sahara. This article sets the background of the significance of FR radiation in the natural environment and its importance for plant growth and development in the hope that it might inform intelligently those concerned with improving the design of plant growth facilities.

  19. Phytochrome-mediated responses: Implications for controlled environment research facilities

    Science.gov (United States)

    Smith, Harry

    1994-01-01

    Light is undoubtedly the most important environmental variable for plant growth and development; plants not only use radiant energy in photosynthesis, they also respond to the quantity, quality, direction and timing of incident radiation through photomorphogenic response that can have huge effects on the rate of growth and the pattern of development. It is surprising, therefore, that the manufacturers and suppliers of controlled environment facilities have been singularly uninventive in the design of the lighting assemblies they provide. The consumer has one choice only - a lighting assembly that provides irradiance levels usually only a fraction of sunlight, and a control system that is limited to regulating the timing of the on-off switch. The reasons for these limitations are partly technological, but in the main they result from ignorance on the part of both the consumer and the manufacturer. A specific and powerful example of this ignorance relates to the importance of the so-called far-red wavelengths (FR = 700-800 nm). Because the human eye can hardly detect wavelengths above 700 nm, and photosynthesis also cuts off at about 700 nm, the majority of plant and crop physiologists are still almost completely unaware that FR radiation can have massive effects on growth rate and development. In consequence, most growth cabinets have light sources based on fluorescent tubes, and provide very little FR apart from that emitted by a token number of small incandescent bulbs. Larger growth facilities often use broader spectrum light sources, but growth facilities that provide the capability to vary the FR incident upon the plants are about as abundant as seals in the Sahara. This article sets the background of the significance of FR radiation in the natural environment and its importance for plant growth and development in the hope that it might inform intelligently those concerned with improving the design of plant growth facilities.

  20. Microbiota Dysbiosis Controls the Neuroinflammatory Response after Stroke.

    Science.gov (United States)

    Singh, Vikramjeet; Roth, Stefan; Llovera, Gemma; Sadler, Rebecca; Garzetti, Debora; Stecher, Bärbel; Dichgans, Martin; Liesz, Arthur

    2016-07-13

    Acute brain ischemia induces a local neuroinflammatory reaction and alters peripheral immune homeostasis at the same time. Recent evidence has suggested a key role of the gut microbiota in autoimmune diseases by modulating immune homeostasis. Therefore, we investigated the mechanistic link among acute brain ischemia, microbiota alterations, and the immune response after brain injury. Using two distinct models of acute middle cerebral artery occlusion, we show by next-generation sequencing that large stroke lesions cause gut microbiota dysbiosis, which in turn affects stroke outcome via immune-mediated mechanisms. Reduced species diversity and bacterial overgrowth of bacteroidetes were identified as hallmarks of poststroke dysbiosis, which was associated with intestinal barrier dysfunction and reduced intestinal motility as determined by in vivo intestinal bolus tracking. Recolonizing germ-free mice with dysbiotic poststroke microbiota exacerbates lesion volume and functional deficits after experimental stroke compared with the recolonization with a normal control microbiota. In addition, recolonization of mice with a dysbiotic microbiome induces a proinflammatory T-cell polarization in the intestinal immune compartment and in the ischemic brain. Using in vivo cell-tracking studies, we demonstrate the migration of intestinal lymphocytes to the ischemic brain. Therapeutic transplantation of fecal microbiota normalizes brain lesion-induced dysbiosis and improves stroke outcome. These results support a novel mechanism in which the gut microbiome is a target of stroke-induced systemic alterations and an effector with substantial impact on stroke outcome. We have identified a bidirectional communication along the brain-gut microbiota-immune axis and show that the gut microbiota is a central regulator of immune homeostasis. Acute brain lesions induced dysbiosis of the microbiome and, in turn, changes in the gut microbiota affected neuroinflammatory and functional outcome

  1. Responsible and controlled use: Older cannabis users and harm reduction.

    Science.gov (United States)

    Lau, Nicholas; Sales, Paloma; Averill, Sheigla; Murphy, Fiona; Sato, Sye-Ok; Murphy, Sheigla

    2015-08-01

    Cannabis use is becoming more accepted in mainstream society. In this paper, we use Zinberg's classic theoretical framework of drug, set, and setting to elucidate how older adult cannabis users managed health, social and legal risks in a context of normalized cannabis use. We present selected findings from our qualitative study of Baby Boomer (born 1946-1964) cannabis users in the San Francisco Bay Area. Data collection consisted of a recorded, in-depth life history interview followed by a questionnaire and health survey. Qualitative interviews were analyzed to discover the factors of cannabis harm reduction from the users' perspectives. Interviewees made harm reduction choices based on preferred cannabis derivatives and routes of administration, as well as why, when, where, and with whom to use. Most interviewees minimized cannabis-related harms so they could maintain social functioning in their everyday lives. Responsible and controlled use was described as moderation of quantity and frequency of cannabis used, using in appropriate settings, and respect for non-users. Users contributed to the normalization of cannabis use through normification. Participants followed rituals or cultural practices, characterized by sanctions that helped define "normal" or "acceptable" cannabis use. Users contributed to cannabis normalization through their harm reduction methods. These cultural practices may prove to be more effective than formal legal prohibitions in reducing cannabis-related harms. Findings also suggest that users with access to a regulated market (medical cannabis dispensaries) were better equipped to practice harm reduction. More research is needed on both cannabis culture and alternative routes of administration as harm reduction methods. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Paxillin controls directional cell motility in response to physical cues.

    Science.gov (United States)

    Sero, Julia E; German, Alexandra E; Mammoto, Akiko; Ingber, Donald E

    2012-01-01

    Physical cues from the extracellular environment that influence cell shape and directional migration are transduced into changes in cytoskeletal organization and biochemistry through integrin-based cell adhesions to extracellular matrix (ECM). Paxillin is a focal adhesion (FA) scaffold protein that mediates integrin anchorage to the cytoskeleton, and has been implicated in regulation of FA assembly and cell migration. To determine whether paxillin is involved in coupling mechanical distortion with directional movement, cell shape was physically constrained by culturing cells on square-shaped fibronectin-coated adhesive islands surrounded by non-adhesive barrier regions that were created with a microcontact printing technique. Square-shaped cells preferentially formed FAs and extended lamellipodia from their corner regions when stimulated with PDGF, and loss of paxillin resulted in loss of this polarized response. Selective expression of the N- and C-terminal domains of paxillin produced opposite, but complementary, effects on suppressing or promoting lamellipodia formation in different regions of square cells, which corresponded to directional motility defects in vitro. Paxillin loss or mutation was also shown to affect the formation of circular dorsal ruffles, and this corresponded to changes in cell invasive behavior in 3D. This commentary addresses the implications of these findings in terms of how a multifunctional FA scaffold protein can link physical cues to cell adhesion, protrusion and membrane trafficking so as to control directional migration in 2D and 3D. We also discuss how microengineered ECM islands and in vivo model systems can be used to further elucidate the functions of paxillin in directional migration.

  3. Responsible and controlled use: Older cannabis users and harm reduction

    Science.gov (United States)

    Lau, Nicholas; Sales, Paloma; Averill, Sheigla; Murphy, Fiona; Sato, Sye-Ok; Murphy, Sheigla

    2015-01-01

    Background Cannabis use is becoming more accepted in mainstream society. In this paper, we use Zinberg’s classic theoretical framework of drug, set, and setting to elucidate how older adult cannabis users managed health, social and legal risks in a context of normalized cannabis use. Methods We present selected findings from our qualitative study of Baby Boomer (born 1946–1964) cannabis users in the San Francisco Bay Area. Data collection consisted of a recorded, in-depth life history interview followed by a questionnaire and health survey. Qualitative interviews were analyzed to discover the factors of cannabis harm reduction from the users’ perspectives. Results Interviewees made harm reduction choices based on preferred cannabis derivatives and routes of administration, as well as why, when, where, and with whom to use. Most interviewees minimized cannabis-related harms so they could maintain social functioning in their everyday lives. Responsible and controlled use was described as moderation of quantity and frequency of cannabis used, using in appropriate settings, and respect for non-users. Users contributed to the normalization of cannabis use through normification. Conclusion Participants followed rituals or cultural practices, characterized by sanctions that helped define “normal” or “acceptable” cannabis use. Users contributed to cannabis normalization through their harm reduction methods. These cultural practices may prove to be more effective than formal legal prohibitions in reducing cannabis-related harms. Findings also suggest that users with access to a regulated market (medical cannabis dispensaries) were better equipped to practice harm reduction. More research is needed on both cannabis culture and alternative routes of administration as harm reduction methods. PMID:25911027

  4. 14 CFR 121.537 - Responsibility for operational control: Supplemental operations.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Responsibility for operational control... § 121.537 Responsibility for operational control: Supplemental operations. (a) Each certificate holder... command and the director of operations are jointly responsible for the initiation, continuation, diversion...

  5. Fighting with Fires: Decentralize Control to Increase Responsiveness

    National Research Council Canada - National Science Library

    Johnson, Robert

    2001-01-01

    .... The examination of theory explains how the Army's centralized control of fires to facilitate massing of fires, coupled with a poorly developed digital fire control system are the root causes of failure...

  6. Controlled response selection benefits explicit, but not implicit sequence learning

    NARCIS (Netherlands)

    Jiménez, L.; Deroost, N.; van den Broek, Egon; Clegg, B.A.; Abrahamse, E.L.

    2010-01-01

    In two experiments with the serial reaction time task the effect of response selection processes on sequence learning was examined by manipulating stimulus-response compatibility between training groups. In Experiment 1 participants were first trained with either compatible or incompatible

  7. Improved Notch Filter For Synchronous-Response Control

    Science.gov (United States)

    Johnson, Bruce G.; Downer, James R.; Eisenhaure, David B.; Hockney, Richard; Misovec, Kathleen

    1991-01-01

    Tracking differential-notch filter (TDNF) developed to retain good synchronous-response performance of notch filter, but with vastly improved stability properties. Measurement error perfectly filtered from feedback signal used to drive compensator. Provides good stability of simple lead/lag compensator combined with good synchronous-response performance gained by addition of notch filter.

  8. Some experiences with active control of aeroelastic response

    Science.gov (United States)

    Newsom, J. R.; Abel, I.

    1981-01-01

    Flight and wind tunnel tests were conducted and multidiscipline computer programs were developed as part of investigations of active control technology conducted at the NASA Langley Research Center. Unsteady aerodynamics approximation, optimal control theory, optimal controller design, and the Delta wing and DC-10 models are described. The drones for aerodynamics and structural testing (DAST program) for evaluating procedures for aerodynamic loads prediction and the design of active control systems on wings with significant aeroelastic effects is described as well as the DAST model used in the wind tunnel tests.

  9. Quality control system response to stochastic growth of amyloid fibrils

    DEFF Research Database (Denmark)

    Pigolotti, Simone; Lizana, Ludvig; Otzen, Daniel

    2013-01-01

    We introduce a stochastic model describing aggregation of misfolded proteins and degradation by the protein quality control system in a single cell. Aggregate growth is contrasted by the cell quality control system, that attacks them at different stages of the growth process, with an efficiency t...

  10. A supervisory approach to microgrid demand response and climate control

    NARCIS (Netherlands)

    Korkas, Christos D.; Baldi, S.; Michailidis, Iakovos; Boutalis, Yiannis; Kosmatopoulos, Elias B.; Antsaklis, Panos J.; Valavanis, Kimon P.; Theiliol, Didier

    2016-01-01

    Microgrids equipped with small-scale renewable-energy generation systems and energy storage units offer challenging opportunity from a control point of view. In fact, in order to improve resilience and enable islanded mode, micro-grid energy management systems must dynamically manage controllable

  11. Magnetoelectrical control of nonreciprocal microwave response in a multiferroic helimagnet

    Science.gov (United States)

    Iguchi, Y.; Nii, Y.; Onose, Y.

    2017-05-01

    The control of physical properties by external fields is essential in many contemporary technologies. For example, conductance can be controlled by a gate electric field in a field effect transistor, which is a main component of integrated circuits. Optical phenomena induced by an electric field such as electroluminescence and electrochromism are useful for display and other technologies. Control of microwave propagation is also important for future wireless communication technology. Microwave properties in solids are dominated mostly by magnetic excitations, which cannot be easily controlled by an electric field. One solution to this problem is to use magnetically induced ferroelectrics (multiferroics). Here we show that microwave nonreciprocity, that is, different refractive indices for microwaves propagating in opposite directions, could be reversed by an external electric field in a multiferroic helimagnet Ba2Mg2Fe12O22. This approach offers an avenue for the electrical control of microwave properties.

  12. Components of asthma control and treatment response of individual control criteria in children

    DEFF Research Database (Denmark)

    Pedersen, Søren; Maspero, Jorge; Gul, Nadeem

    2011-01-01

    The aim of asthma management is to achieve and maintain clinical control. Control data for children is sparse.......The aim of asthma management is to achieve and maintain clinical control. Control data for children is sparse....

  13. A Decentralized Current-Sharing Controller Endows Fast Transient Response to Parallel DC-DC Converters

    DEFF Research Database (Denmark)

    Wang, Haojie; Han, Minxiao; Han, Renke

    2017-01-01

    This paper proposes a decentralized current-sharing control strategy to endow fast transient response to paralleled DC-DC converters systems, such as DC microgrids or distributed power systems. The proposed controller consist of two main control loops: an external voltage droop control for curren...

  14. Functional response of Xylocoris falvipes , a biological control agent ...

    African Journals Online (AJOL)

    The warehouse pirate bug Xylocoris falvipes is an opportunist predator of many stored product insect pests. Its functional response in relationship with variable densities of prey appears as the Holling\\'s type II model. The predator X. falvipes, collected within small holder granaries in Mayo Danay division in the far North ...

  15. Buffeting Response of Suspension Bridge Girder with Separate Control Flaps

    DEFF Research Database (Denmark)

    Huynh, Truc; Thoft-Christensen, Palle

    is of interest. The RMS response is determined on the basis of the equation of motion, which is formulated stochastically according to the wind random turbulence components. It is further assumed that the sum of the motion-induced forces and the buffeting-induced forces from the girder and the flaps is computed...

  16. Controlling ethylene responses in flowers at the receptor level

    NARCIS (Netherlands)

    Serek, M.; Woltering, E.J.; Sisler, E.C.; Frello, S.; Sriskandarajah, S.

    2006-01-01

    For a vast number of ornamental species, blocking the plant¿s response to ethylene is an efficient strategy to enhance the longevity of the flowers. The most effective ways to conduct such interference will be reviewed in this paper. A large number of chemical compounds have been evaluated for their

  17. Geography and plumbing control the T cell response to infection.

    Science.gov (United States)

    Khanna, Kamal M; Lefrançois, Leo

    2008-07-01

    The orchestrated movement of cells of the immune system is essential to generation of productive responses leading to protective memory development. Recent advances have allowed the direct microscopic visualization of lymphocyte and antigen-presenting cell migration and interaction during immune response initiation and progression. These studies have defined important characteristics of the microanatomy of lymphocyte movement, particularly in the lymph node. Moreover, the ability to track endogenous antigen-specific T cells has revealed a coordinated pathway of CD8 T cell movement in the spleen following primary and secondary infection. As a consequence, the local anatomy of secondary lymphoid tissues during infection has emerged as a critical regulator of immunity. While some of the factors responsible for the migratory cues instructing immune cell movement have been identified, much remains to be learned. Here, we provide a brief overview of studies examining CD8 T cell localization during the immune response to infection in the context of our current understanding of immune system structure.

  18. Effects of Trait Self-Control on Response Conflict About Healthy and Unhealthy Food.

    Science.gov (United States)

    Gillebaart, Marleen; Schneider, Iris K; De Ridder, Denise T D

    2016-12-01

    Self-control leads to positive life outcomes, but it is poorly understood. While previous research has focused on self-control failure, self-control success remains unexplored. The current studies aim to shed more light on the mechanisms of self-control by focusing on the resolution of response conflict as a key component in self-control success. Trait self-control was measured, and participants reported on the magnitude of response conflict they experienced about healthy and unhealthy foods in Study 1 (N = 146; M age  = 33.03; 59 females, 83 males, 4 unknown). The response conflict process was assessed in Study 2 (N = 118; M age  = 21.45; 68 females, 41 males, 9 unknown). Outcomes showed that self-reported evaluative response conflict about food items was smaller for people high in trait self-control. Study 2 revealed that higher trait self-control predicted faster resolution of self-control conflict, and an earlier peak of the response conflict. Taken together, these results provide insight into what makes people with high trait self-control successful, namely, how they handle response conflict. Implications for self-control theories and future directions are discussed. © 2015 Wiley Periodicals, Inc.

  19. Electrooptic Modulators with Controlled Frequency Responses by Using Nonperiodically Polarization-Reversed Structure

    Directory of Open Access Journals (Sweden)

    Ha Viet Pham

    2008-01-01

    Full Text Available We discuss a new method to design traveling-wave electrooptic modulators with controlled frequency responses using nonperiodically polarization-reversed structure. Using our method, the frequency responses of both magnitude and phase of modulation index are controllable. Several electrooptic modulators for advanced modulation formats such as duobinary modulation and wideband single-sideband modulation are proposed.

  20. pH Responsive Microcapsules for Corrosion Control

    Science.gov (United States)

    Calle, Luz Marina; Li, Wenyan; Muehlberg, Aaron; Boraas, Samuel; Webster, Dean; JohnstonGelling, Victoria; Croll, Stuart; Taylor, S Ray; Contu, Francesco

    2008-01-01

    The best coatings for corrosion protection provide not only barriers to the environment, but also a controlled release of a corrosion inhibitor, as demanded by the presence of corrosion or mechanical damage. NASA has developed pH sensitive microcapsules (patent pending) that can release their core contents when corrosion starts. The objectives of the research presented here were to encapsulate non-toxic corrosion inhibitors, to incorporate the encapsulated inhibitors into paint formulations, and to test the ability of the paints to control corrosion. Results showed that the encapsulated corrosion inhibitors, specifically Ce(NO3)3 , are effective to control corrosion over long periods of time when incorporated at relatively high pigment volume concentrations into a paint formulation.

  1. Effortless self-control : A novel perspective on response conflict strategies in trait self-control

    NARCIS (Netherlands)

    Gillebaart, Marleen|info:eu-repo/dai/nl/344390365; de Ridder, Denise T D|info:eu-repo/dai/nl/070706174

    Self-control is of invaluable importance for well-being. While previous research has focused on self-control failure, we introduce a new perspective on self-control, including the notion of effortless self-control, and a focus on self-control success rather than failure. We propose that effortless

  2. PID Controller Settings Based on a Transient Response Experiment

    Science.gov (United States)

    Silva, Carlos M.; Lito, Patricia F.; Neves, Patricia S.; Da Silva, Francisco A.

    2008-01-01

    An experimental work on controller tuning for chemical engineering undergraduate students is proposed using a small heat exchange unit. Based upon process reaction curves in open-loop configuration, system gain and time constant are determined for first order model with time delay with excellent accuracy. Afterwards students calculate PID…

  3. Connected Cruise Control: Driver response to the advisory system

    NARCIS (Netherlands)

    Martens, Marieke Hendrikje; Risto, Malte; Wilschut, E.S.

    2011-01-01

    Connected Cruise Control (CCC) is a system, that is currently under development within a HTAS project. CCC aims to improve throughput in dense motorway traffic by advising drivers how to drive. The advice will integrate a lane advice, a headway advice and speed advice. The CCC advice will be

  4. Controlled release of diclofenac sodium from pH-responsive ...

    Indian Academy of Sciences (India)

    In this paper, controlled release of diclofenac sodium (DS) from pH-sensitive carrageenan-gpoly(acrylic acid) superabsorbent hydrogels was investigated. The hydrogels were prepared by graft copolymerization of acrylic acid (AA) onto kappa-carrageenan, using ammonium persulfate (APS) as a free radical initiator in the ...

  5. Chirality controlled responsive self-assembled nanotubes in water

    NARCIS (Netherlands)

    van Dijken, D. J.; Stacko, P.; Stuart, M. C. A.; Browne, W. R.; Feringa, B. L.

    2017-01-01

    The concept of using chirality to dictate dimensions and to store chiral information in self-assembled nanotubes in a fully controlled manner is presented. We report a photoresponsive amphiphile that co-assembles with its chiral counterpart to form nanotubes and demonstrate how chirality can be used

  6. Response of maize and cucumber intercrop to soil moisture control ...

    African Journals Online (AJOL)

    Replicate field plots were used in experiments aimed at evaluating the yield potentials of maize and cucumber intercrop resulting from the control of soil moisture through irrigation and mulching, for a period of eleven weeks. Three irrigation depths, 2.5, 3.5 and 4.5 mm; and two mulch levels, zero mulch and 10 ton/ha of oil ...

  7. Design PID controllers for desired time-domain or frequency-domain response.

    Science.gov (United States)

    Zhang, Weidong; Xi, Yugeng; Yang, Genke; Xu, Xiaoming

    2002-10-01

    Practical requirements on the design of control systems, especially process control systems, are usually specified in terms of time-domain response, such as overshoot and rise time, or frequency-domain response, such as resonance peak and stability margin. Although numerous methods have been developed for the design of the proportional-integral-derivative (PID) controller, little work has been done in relation to the quantitative time-domain and frequency-domain responses. In this paper, we study the following problem: Given a nominal stable process with time delay, we design a suboptimal PID controller to achieve the required time-domain response or frequency-domain response for the nominal system or the uncertain system. An H(infinity) PID controller is developed based on optimal control theory and the parameters are derived analytically. Its properties are investigated and compared with that of two developed suboptimal controllers: an H2 PID controller and a Maclaurin PID controller. It is shown that all three controllers can provide the quantitative time-domain and frequency-domain responses.

  8. Performance Assessment of Aggregation Control Services for Demand Response

    DEFF Research Database (Denmark)

    Bondy, Daniel Esteban Morales; Costanzo, Giuseppe Tommaso; Heussen, Kai

    2014-01-01

    . This paper formulates performance measures and an index to evaluate in hind sight the quality of service delivery by an aggregator, both with respect to ancillary service and asset management service. The index is based on requirements formulated in service contracts and provides an overall assessment......Aggregation algorithms that provide services to the grid via demand side management are moving from research ideas to the market. With the diversity of the technology delivering such services, it becomes essential to establish transparent performance standards from a service delivery perspective...... of the quality of service provided by an aggregation control algorithm. By a detailed case study we present and an application of the index, comparing the performance of two different control architectures for demand side management delivering a distribution grid service....

  9. Population response of rodents to control with rodenticides

    Directory of Open Access Journals (Sweden)

    A.V. TCHABOVSKY

    2009-04-01

    Full Text Available We summarize theoretical approaches and practice of rodent pest control in Russia and former USSR during last 50 years. We review literature as well as original data to understand mechanisms of rodent populations recovery after chemical control campaigns in urban areas, agricultural lands and natural foci of plague. Laboratory and field experiments indicate that inherent individual variation in behavioural, physiological and life-history traits provides survival of heterogeneous mix of individuals in residual population with increased resistance to poisonous baits and high reproductive potential that leads to fast recovery of a population. In a series of field experiments with various rodent and lagomorph species (Mus musculus, Rattus norvegicus, Meriones unguiculatus, M.meridianus, M.tamariscinus, Ochotona pallasii we have shown that patterns of recolonization of depopulated area and mechanisms of population recovery vary among species and depend on species-specific social organization. After control territorial and group-living species demonstrated an increase in mobility and affiliative and marking behaviour and a decrease in intraspecific aggression. The rate of recolonization of treated areas was high due to redistribution of survived individuals and immigration by neighbors. Population recovered to original level due to increased breeding performance and fecundity of both survived residents and immigrants. In contrast, socially-independent species exhibited minor changes in behaviour. Recolonization was mainly due to better survival and recruitment of youngs, so the rate of recolonization was low. Species-specificity of behavioural compensation mechanisms to control should be considered when developing ecologically based rodent management strategies.

  10. The wound repair response controls outcome to cutaneous leishmaniasis

    Science.gov (United States)

    Sakthianandeswaren, Anuratha; Elso, Colleen M.; Simpson, Ken; Curtis, Joan M.; Kumar, Beena; Speed, Terence P.; Handman, Emanuela; Foote, Simon J.

    2005-01-01

    Chronic microbial infections are associated with fibrotic and inflammatory reactions known as granulomas showing similarities to wound-healing and tissue repair processes. We have previously mapped three leishmaniasis susceptibility loci, designated lmr1, -2, and -3, which exert their effect independently of T cell immune responses. Here, we show that the wound repair response is critically important for the rapid cure in murine cutaneous leishmaniasis caused by Leishmania major. Mice congenic for leishmaniasis resistance loci, which cured their lesions more rapidly than their susceptible parents, also expressed differentially genes involved in tissue repair, laid down more ordered collagen fibers, and healed punch biopsy wounds more rapidly. Fibroblast monolayers from these mice repaired in vitro wounds faster, and this process was accelerated by supernatants from infected macrophages. Because these effects are independent of T cell-mediated immunity, we conclude that the rate of wound healing is likely to be an important component of innate immunity involved in resistance to cutaneous leishmaniasis. PMID:16223880

  11. Mitochondrial respiration controls lysosomal function during inflammatory T cell responses

    Science.gov (United States)

    Baixauli, Francesc; Acín-Pérez, Rebeca; Villarroya-Beltrí, Carolina; Mazzeo, Carla; Nuñez-Andrade, Norman; Gabandé-Rodriguez, Enrique; Dolores Ledesma, Maria; Blázquez, Alberto; Martin, Miguel Angel; Falcón-Pérez, Juan Manuel; Redondo, Juan Miguel; Enríquez, Jose Antonio; Mittelbrunn, Maria

    2016-01-01

    Summary The endolysosomal system is critical for the maintenance of cellular homeostasis. However, how endolysosomal compartment is regulated by mitochondrial function is largely unknown. We have generated a mouse model with defective mitochondrial function in CD4+ T lymphocytes by genetic deletion of the mitochondrial transcription factor A (Tfam). Mitochondrial respiration-deficiency impairs lysosome function, promotes p62 and sphingomyelin accumulation and disrupts endolysosomal trafficking pathways and autophagy, thus linking a primary mitochondrial dysfunction to a lysosomal storage disorder. The impaired lysosome function in Tfam-deficient cells subverts T cell differentiation toward pro-inflammatory subsets and exacerbates the in vivo inflammatory response. Restoration of NAD+ levels improves lysosome function and corrects the inflammatory defects in Tfam-deficient T cells. Our results uncover a mechanism by which mitochondria regulate lysosome function to preserve T cell differentiation and effector functions, and identify novel strategies for intervention in mitochondrial-related diseases. PMID:26299452

  12. A Precise Temperature-Responsive Bistable Switch Controlling Yersinia Virulence.

    Directory of Open Access Journals (Sweden)

    Aaron Mischa Nuss

    2016-12-01

    Full Text Available Different biomolecules have been identified in bacterial pathogens that sense changes in temperature and trigger expression of virulence programs upon host entry. However, the dynamics and quantitative outcome of this response in individual cells of a population, and how this influences pathogenicity are unknown. Here, we address these questions using a thermosensing virulence regulator of an intestinal pathogen (RovA of Yersinia pseudotuberculosis as a model. We reveal that this regulator is part of a novel thermoresponsive bistable switch, which leads to high- and low-invasive subpopulations within a narrow temperature range. The temperature range in which bistability is observed is defined by the degradation and synthesis rate of the regulator, and is further adjustable via a nutrient-responsive regulator. The thermoresponsive switch is also characterized by a hysteretic behavior in which activation and deactivation occurred on vastly different time scales. Mathematical modeling accurately mirrored the experimental behavior and predicted that the thermoresponsiveness of this sophisticated bistable switch is mainly determined by the thermo-triggered increase of RovA proteolysis. We further observed RovA ON and OFF subpopulations of Y. pseudotuberculosis in the Peyer's patches and caecum of infected mice, and that changes in the RovA ON/OFF cell ratio reduce tissue colonization and overall virulence. This points to a bet-hedging strategy in which the thermoresponsive bistable switch plays a key role in adapting the bacteria to the fluctuating conditions encountered as they pass through the host's intestinal epithelium and suggests novel strategies for the development of antimicrobial therapies.

  13. RpoS controls the Vibrio cholerae mucosal escape response.

    Directory of Open Access Journals (Sweden)

    Alex Toftgaard Nielsen

    2006-10-01

    Full Text Available Vibrio cholerae causes a severe diarrhoeal disease by secreting a toxin during colonization of the epithelium in the small intestine. Whereas the initial steps of the infectious process have been intensively studied, the last phases have received little attention. Confocal microscopy of V. cholerae O1-infected rabbit ileal loops captured a distinctive stage in the infectious process: 12 h post-inoculation, bacteria detach from the epithelial surface and move into the fluid-filled lumen. Designated the "mucosal escape response," this phenomenon requires RpoS, the stationary phase alternative sigma factor. Quantitative in vivo localization assays corroborated the rpoS phenotype and showed that it also requires HapR. Expression profiling of bacteria isolated from ileal loop fluid and mucus demonstrated a significant RpoS-dependent upregulation of many chemotaxis and motility genes coincident with the emigration of bacteria from the epithelial surface. In stationary phase cultures, RpoS was also required for upregulation of chemotaxis and motility genes, for production of flagella, and for movement of bacteria across low nutrient swarm plates. The hapR mutant produced near-normal numbers of flagellated cells, but was significantly less motile than the wild-type parent. During in vitro growth under virulence-inducing conditions, the rpoS mutant produced 10- to 100-fold more cholera toxin than the wild-type parent. Although the rpoS mutant caused only a small over-expression of the genes encoding cholera toxin in the ileal loop, it resulted in a 30% increase in fluid accumulation compared to the wild-type. Together, these results show that the mucosal escape response is orchestrated by an RpoS-dependent genetic program that activates chemotaxis and motility functions. This may furthermore coincide with reduced virulence gene expression, thus preparing the organism for the next stage in its life cycle.

  14. Bilingualism increases neural response consistency and attentional control: Evidence for sensory and cognitive coupling

    Science.gov (United States)

    Krizman, Jennifer; Skoe, Erika; Marian, Viorica; Kraus, Nina

    2014-01-01

    Auditory processing is presumed to be influenced by cognitive processes – including attentional control – in a top-down manner. In bilinguals, activation of both languages during daily communication hones inhibitory skills, which subsequently bolster attentional control. We hypothesize that the heightened attentional demands of bilingual communication strengthens connections between cognitive (i.e., attentional control) and auditory processing, leading to greater across-trial consistency in the auditory evoked response (i.e., neural consistency) in bilinguals. To assess this, we collected passively-elicited auditory evoked responses to the syllable [da] and separately obtained measures of attentional control and language ability in adolescent Spanish-English bilinguals and English monolinguals. Bilinguals demonstrated enhanced attentional control and more consistent brainstem and cortical responses. In bilinguals, but not monolinguals, brainstem consistency tracked with language proficiency and attentional control. We interpret these enhancements in neural consistency as the outcome of strengthened attentional control that emerged from experience communicating in two languages. PMID:24413593

  15. Compartmentalization of GPCR signalling controls unique cellular responses.

    Science.gov (United States)

    Ellisdon, Andrew M; Halls, Michelle L

    2016-04-15

    With >800 members, G protein-coupled receptors (GPCRs) are the largest class of cell-surface signalling proteins, and their activation mediates diverse physiological processes. GPCRs are ubiquitously distributed across all cell types, involved in many diseases and are major drug targets. However, GPCR drug discovery is still characterized by very high attrition rates. New avenues for GPCR drug discovery may be provided by a recent shift away from the traditional view of signal transduction as a simple chain of events initiated from the plasma membrane. It is now apparent that GPCR signalling is restricted to highly organized compartments within the cell, and that GPCRs activate distinct signalling pathways once internalized. A high-resolution understanding of how compartmentalized signalling is controlled will probably provide unique opportunities to selectively and therapeutically target GPCRs. © 2016 Authors; published by Portland Press Limited.

  16. Assessment of Ilam Reservoir Eutrophication Response in Controlling Water Inflow

    Directory of Open Access Journals (Sweden)

    Fereshteh Nourmohammadi Dehbalaei

    2016-12-01

    Full Text Available In this research, a 2D laterally averaged model of hydrodynamics and water quality, CE-QUAL-W2, was applied to simulate water quality parameters in the Ilam reservoir. The water quality of Ilam reservoir was obtained between mesotrophic and eutrophic based on the measured data including chlorophyll a, total phosphorus and subsurface oxygen saturation. The CE-QUAL-W2 model was calibrated and verified by using the data of the year 2009 and 2010, respectively. Nutrients, chlorophyll a and dissolved oxygen were the water quality constituents simulated by the CE-QUAL-W2 model. The comparison of the simulated water surface elevation with the measurement records indicated that the flow was fully balanced in the numerical model. There was a good agreement between the simulated and measured results of the hydrodynamics and water quality constituents in the calibration and verification periods. Some scenarios have been made base on decreasing in water quantity and nutrient inputs of reservoir inflows. The results have shown that the water quality improvements of the Ilam reservoir will not be achieved by reducing a portion of the reservoir inflow. The retention time of water in reservoir would be changed by decreasing of inflows and it made of the negative effects on the chlorophyll-a concentration by reduction of nutrient inputs and keeping constant of discharge inflow to reservoir, the concentration of total phosphorus would be significantly changed and also the concentration of chlorophyll-a was constant approximately. Thus, the effects of control in nutrient inputs are much more than control in discharge inflows in the Ilam reservoir.

  17. Response Time Analysis of Messages in Controller Area Network: A Review

    Directory of Open Access Journals (Sweden)

    Gerardine Immaculate Mary

    2013-01-01

    Full Text Available This paper reviews the research work done on the response time analysis of messages in controller area network (CAN from the time CAN specification was submitted for standardization (1990 and became a standard (1993 up to the present (2012. Such research includes the worst-case response time analysis which is deterministic and probabilistic response time analysis which is stochastic. A detailed view on both types of analyses is presented here. In addition to these analyses, there has been research on statistical analysis of controller area network message response times.

  18. Updating metacognitive control in response to expected retention intervals.

    Science.gov (United States)

    Fiechter, Joshua L; Benjamin, Aaron S

    2017-04-01

    In five experiments, we investigated whether expected retention intervals affect subjects' encoding strategies. In the first four experiments, our subjects studied paired associates consisting of words from the Graduate Record Exam and a synonym. They were told to expect a test on a word pair after either a short or a longer interval. Subjects were tested on most pairs after the expected retention interval. For some pairs, however, subjects were tested after the other retention interval, allowing for a comparison of performance at a given retention interval conditional upon the expected retention interval. No effect of the expected retention interval was found for 1 min versus 4 min (Exp. 1), 30 s versus 3 min (Exp. 2), and 30 s versus 10 min (Exps. 3 and 4), even when subjects were given complete control over the pacing of study items (Exp. 4). However, when the difference between the expected retention intervals was increased massively (10 min vs. 24 h; Exp. 5), subjects remembered more items that they expected to be tested sooner, an effect consistent with the idea that they traded off efforts to remember items for the later test versus items that were about to be tested. Overall, this set of results accords with much of the test-expectancy literature, revealing that subjects are often reluctant to adjust encoding strategies on an item-by-item basis, and when they do, they usually make quantitative, rather than qualitative, adjustments.

  19. Response time and noise power gain of electrical substitution radiometers with feedback control.

    Science.gov (United States)

    Clare, J F; White, D R

    1989-08-15

    We present criteria for choosing filter and control parameters for absolute radiometers and true RMS meters that employ feedback controlled electrical substitution. Expressions are obtained for the response of the electrical heating power to radiation and to detector noise. The gains and time constants that minimize the response time for a given variance in a single power measurement are obtained from analyses of second- and third-order systems. Near optimal behavior is obtained in the third-order system comprising a first-order filter and a proportional-plus-integral controller with an integration time equal to the detector time constant. A procedure for tuning the control system is presented.

  20. Immune response to Varicella vaccine in children with atopic dermatitis compared to non-atopic controls

    OpenAIRE

    Schneider, Lynda; Weinberg, Adriana; Boguniewicz, Mark; Taylor, Patricia; Oettgen, Hans; Heughan, Lisa; Zaccaro, Daniel; Armstrong, Brian; Holliday, Aaron; Leung, Donald Y. M.

    2010-01-01

    Atopic dermatitis subjects and controls had similar cellular immune responses to Varicella vaccine. Atopic dermatitis subjects with a history of eczema herpeticum made high levels of Varicella specific IgE.

  1. Muscle oxygenation, EMG, and cardiovascular responses for cabin attendants vs. controls

    DEFF Research Database (Denmark)

    Sandfeld, Jesper; Larsen, Lisbeth Højkjær; Crenshaw, Albert Guy

    2013-01-01

    The goal was to investigate the effect of acute moderate hypobaric exposure on the physiological responses to sustained contractions (local) and light to moderate dynamic exercise (systemic) for cabin attendants (CAB) and a matched control group (CON)....

  2. Command and Control of Special Operations Forces Missions in the US Northern Command Area of Responsibility

    National Research Council Canada - National Science Library

    McGregor, Ottis W., III

    2005-01-01

    The need for a well thought out, planned, and rehearsed command and control organization to conduct special operations in the US Northern Command Area of Responsibility is vital to success in defending the Homeland...

  3. Testing interactive effects of automatic and conflict control processes during response inhibition - A system neurophysiological study.

    Science.gov (United States)

    Chmielewski, Witold X; Beste, Christian

    2017-02-01

    In everyday life successful acting often requires to inhibit automatic responses that might not be appropriate in the current situation. These response inhibition processes have been shown to become aggravated with increasing automaticity of pre-potent response tendencies. Likewise, it has been shown that inhibitory processes are complicated by a concurrent engagement in additional cognitive control processes (e.g. conflicting monitoring). Therefore, opposing processes (i.e. automaticity and cognitive control) seem to strongly impact response inhibition. However, possible interactive effects of automaticity and cognitive control for the modulation of response inhibition processes have yet not been examined. In the current study we examine this question using a novel experimental paradigm combining a Go/NoGo with a Simon task in a system neurophysiological approach combining EEG recordings with source localization analyses. The results show that response inhibition is less accurate in non-conflicting than in conflicting stimulus-response mappings. Thus it seems that conflicts and the resulting engagement in conflict monitoring processes, as reflected in the N2 amplitude, may foster response inhibition processes. This engagement in conflict monitoring processes leads to an increase in cognitive control, as reflected by an increased activity in the anterior and posterior cingulate areas, while simultaneously the automaticity of response tendencies is decreased. Most importantly, this study suggests that the quality of conflict processes in anterior cingulate areas and especially the resulting interaction of cognitive control and automaticity of pre-potent response tendencies are important factors to consider, when it comes to the modulation of response inhibition processes. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Genetics of mechanisms controlling responses to two major pathogens in broiler and layer chickens

    DEFF Research Database (Denmark)

    Hamzic, Edin

    The objective of this thesis was to improve the understanding of molecular mechanisms controlling the response to two major pathogens, Eimeria maxima (coccidiosis) and infectious bronchitis virus (IBV), in broiler and layer chickens, respectively. Breeding for the improved response to the two...

  5. Spinal sensory projection neuron responses to spinal cord stimulation are mediated by circuits beyond gate control.

    Science.gov (United States)

    Zhang, Tianhe C; Janik, John J; Peters, Ryan V; Chen, Gang; Ji, Ru-Rong; Grill, Warren M

    2015-07-01

    Spinal cord stimulation (SCS) is a therapy used to treat intractable pain with a putative mechanism of action based on the Gate Control Theory. We hypothesized that sensory projection neuron responses to SCS would follow a single stereotyped response curve as a function of SCS frequency, as predicted by the Gate Control circuit. We recorded the responses of antidromically identified sensory projection neurons in the lumbar spinal cord during 1- to 150-Hz SCS in both healthy rats and neuropathic rats following chronic constriction injury (CCI). The relationship between SCS frequency and projection neuron activity predicted by the Gate Control circuit accounted for a subset of neuronal responses to SCS but could not account for the full range of observed responses. Heterogeneous responses were classifiable into three additional groups and were reproduced using computational models of spinal microcircuits representing other interactions between nociceptive and nonnociceptive sensory inputs. Intrathecal administration of bicuculline, a GABAA receptor antagonist, increased spontaneous and evoked activity in projection neurons, enhanced excitatory responses to SCS, and reduced inhibitory responses to SCS, suggesting that GABAA neurotransmission plays a broad role in regulating projection neuron activity. These in vivo and computational results challenge the Gate Control Theory as the only mechanism underlying SCS and refine our understanding of the effects of SCS on spinal sensory neurons within the framework of contemporary understanding of dorsal horn circuitry. Copyright © 2015 the American Physiological Society.

  6. Children's Responses to Daily Social Stressors: Relations with Parenting, Children's Effortful Control, and Adjustment

    Science.gov (United States)

    Valiente, Carlos; Lemery-Chalfant, Kathryn; Swanson, Jodi

    2009-01-01

    Background: We examined children's coping and involuntary stress responses as mediators of the relations between parenting or children's effortful control (EC) and adjustment. Method: Two hundred and forty primarily Mexican American 7- to 12-year-old children reported on their EC, coping, involuntary stress responses, and problem behaviors.…

  7. Response Time Analysis of Messages in Controller Area Network: A Review

    OpenAIRE

    Gerardine Immaculate Mary; Z. C. ALEX; Lawrence Jenkins

    2013-01-01

    This paper reviews the research work done on the response time analysis of messages in controller area network (CAN) from the time CAN specification was submitted for standardization (1990) and became a standard (1993) up to the present (2012). Such research includes the worst-case response time analysis which is deterministic and probabilistic response time analysis which is stochastic. A detailed view on both types of analyses is presented here. In addition to these analyses, there has been...

  8. Experimental Determination of Demand Response Control Models and Cost of Control for Ensembles of Window-Mount Air Conditioners

    Energy Technology Data Exchange (ETDEWEB)

    Geller, Drew Adam [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Backhaus, Scott N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-29

    Control of consumer electrical devices for providing electrical grid services is expanding in both the scope and the diversity of loads that are engaged in control, but there are few experimentally-based models of these devices suitable for control designs and for assessing the cost of control. A laboratory-scale test system is developed to experimentally evaluate the use of a simple window-mount air conditioner for electrical grid regulation services. The experimental test bed is a single, isolated air conditioner embedded in a test system that both emulates the thermodynamics of an air conditioned room and also isolates the air conditioner from the real-world external environmental and human variables that perturb the careful measurements required to capture a model that fully characterizes both the control response functions and the cost of control. The control response functions and cost of control are measured using harmonic perturbation of the temperature set point and a test protocol that further isolates the air conditioner from low frequency environmental variability.

  9. A frequency response model matching method for PID controller design for processes with dead-time.

    Science.gov (United States)

    Anwar, Md Nishat; Pan, Somnath

    2015-03-01

    In this paper, a PID controller design method for the integrating processes based on frequency response matching is presented. Two approaches are proposed for the controller design. In the first approach, a double feedback loop configuration is considered where the inner loop is designed with a stabilizing gain. In the outer loop, the parameters of the PID controller are obtained by frequency response matching between the closed-loop system with the PID controller and a reference model with desired specifications. In the second approach, the design is directly carried out considering a desired load-disturbance rejection model of the system. In both the approaches, two low frequency points are considered for matching the frequency response, which yield linear algebraic equations, solution of which gives the controller parameters. Several examples are taken from the literature to demonstrate the effectiveness and to compare with some well known design methods. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  10. REGULATION OF IMMUNE RESPONSE OF PATIENTS WITH PARTIALLY CONTROLLED vs CONTROLLED BRONCHIAL ASTHMA

    Directory of Open Access Journals (Sweden)

    E. Yu. Barabash

    2017-01-01

    Full Text Available A control group included seventeen conditionally healthy people (Group 1. Eighty-eight patients with proven bronchial asthma (BA at the age of 22 to 48 were enrolled into the study. I.e., Group 2 included nine patients with well-controlled BA. Group 3 included persons with partially controlled BA (n=79. There were 8 people with easily treated BA in group 2, and 57 such cases in Group 3. The levels of interleukins (IL-4, IL-10, IL-17A, interferon-γ (IFNγ, and tumor-α necrosis factor (TNFα were monitored by means of flow cytometry technique. The parameters of cellular immunity were registered by flow cytofluorimetry assays. Phagocytosis indicators were studied by means of D. Mayansky method, metabolic activity of neutrophils, by the B.Park method, as modified by E.Shmelev. Evaluation of cellular immunity did not reveal statistically significant differences for distinct CD subpopulations between healthy controls and BA patients. The patients with controlled and partially controlled BA exhibited some changes in cytokine concentrations, i.e., increased IL-4, IL-17А, IL-10 and TNFα levels; changes in phagocytosis and oxygen dependent bactericidal activities of neutrophils. We have revealed higher concentrations of IL-4, IL-17А in the less controlled BA (group 3 , as compared with group 2. TNFα induction remained at significantly higher level in both groups of BA patients, exceeding mean control values by 2.3 times. The degree of IL-10 production in group 2 with controlled BA was significantly higher than in group with partial disease control (group 3, p < 0.001, thus suggesting application of IL-10 levels as an index of active inflammation control. Patients with BA (groups 2, 3 exhibited a decrease of basal IFNγ, as compared to healthy people (p < 0.001. In group 3 (partial control, this parameter was 3-fold lower than in healthy persons. Evaluation of monocyte/phagocyte functions showed statistically significant differences between BA

  11. A randomized controlled trial comparing instructions regarding unsafe response options in a MCQ examination.

    Science.gov (United States)

    Tweed, Mike; Wilkinson, Tim

    2009-01-01

    Marking of multiple choice type examinations often just takes account of the correct responses. This may encourage guessing of incorrect and potentially unsafe responses. Ideally responses should contain a high proportion of correct, unsafe and the use of 'don't know' response rather than incorrect. This study explored the effect of instructions on responses. Fourth- and fifth-year students sitting for an optional multiple choice examination were randomized to receive one of four instruction options: number-correct marking (the control group); alert to unsafe; mark deduction for unsafe; or correction for guessing. A total of 210 students sat the test. For the fourth-year cohort, compared with the control group, being alerted to unsafe and mark deduction for unsafe or incorrect responses were associated with graduated increases in the use of 'don't know' and reductions in incorrect responses. For the fifth-year cohort, there were no differences in responses between options. The fifth-year cohort, gave more correct, and fewer incorrect, unsafe and 'don't know' responses. Both the year group and instructions had an effect. Being alerted to potentially unsafe responses, even when there is no mark deduction penalty, had an effect, although mark deduction still had the greatest effect. Assessment instructions may give subliminal messages that have important consequences.

  12. 32 CFR 700.1138 - Responsibilities concerning marijuana, narcotics, and other controlled substances.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 5 2010-07-01 2010-07-01 false Responsibilities concerning marijuana, narcotics... concerning marijuana, narcotics, and other controlled substances. (a) All personnel shall endeavor to prevent and eliminate the unauthorized use of marijuana, narcotics and other controlled substances within the...

  13. LQG Control of Along-Wind Response of a Tall Building with an ATMD

    Directory of Open Access Journals (Sweden)

    Ki-Pyo You

    2014-01-01

    Full Text Available Modern tall buildings use lighter construction materials that have high strength and less stiffness and are more flexible. Although this results in the improvement of structural safety, excessive wind-induced excitations could lead to occupant discomfort. The optimal control law of a linear quadratic Gaussian (LQG controller with an active tuned mass damper (ATMD is used for reducing the along-wind response of a tall building. ATMD consists of a second mass with optimum parameters for tuning frequency and damping ratio of the tuned mass damper (TMD, under the stationary random load, was used. A fluctuating along-wind load, acting on a tall building, was treated as a stationary Gaussian white noise and was simulated numerically, in the time domain, using the along-wind load spectra proposed by G. Solari in 1993. Using this simulated wind load, it was possible to calculate the along-wind responses of a tall building (with and without the ATMD, using an LQG controller. Comparing the RMS (root mean square response revealed that the numerically simulated along-wind responses, without ATMD, are a good approximation to the closed form response, and that the reduced responses with ATMD and LQG controller were estimated by varying the values of control design parameters.

  14. PID controller auto-tuning based on process step response and damping optimum criterion.

    Science.gov (United States)

    Pavković, Danijel; Polak, Siniša; Zorc, Davor

    2014-01-01

    This paper presents a novel method of PID controller tuning suitable for higher-order aperiodic processes and aimed at step response-based auto-tuning applications. The PID controller tuning is based on the identification of so-called n-th order lag (PTn) process model and application of damping optimum criterion, thus facilitating straightforward algebraic rules for the adjustment of both the closed-loop response speed and damping. The PTn model identification is based on the process step response, wherein the PTn model parameters are evaluated in a novel manner from the process step response equivalent dead-time and lag time constant. The effectiveness of the proposed PTn model parameter estimation procedure and the related damping optimum-based PID controller auto-tuning have been verified by means of extensive computer simulations. © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

  15. A Decentralized Current-Sharing Controller Endows Fast Transient Response to Parallel DC-DC Converters

    DEFF Research Database (Denmark)

    Wang, Haojie; Han, Minxiao; Han, Renke

    2017-01-01

    to the external control loop simplification, plays a major role in the system bandwidth, so that an adaptive PI controller is proposed for this matter. In the paper, two different droop control methods have been modeling, designed, simulated, and tested: the conventional virtual-impedance-loop based V-I droop...... that of the conventional V-I droop control. Furthermore, by analyzing the effects from I-V droop control parameters, the errors can be reduced faster by enlarging the proportional terms, but with no fluctuations, and then completely eliminated by restoring back to small proportional values. Meanwhile, there exists a trade......-off phenomenon between the fast dynamic response and good steady-state performance, thus an adaptive PI controller is proposed to both improve dynamic response and guarantee good steady-state performance simultaneously. Experimental results are shown to verify the accuracy of the models and the effectiveness...

  16. Modifications of Control Loop to Improve the Depth Response of Autonomous Underwater Vehicles

    Directory of Open Access Journals (Sweden)

    Sheng-Ping Hsu

    2014-01-01

    Full Text Available During a constant depth maneuver of an autonomous underwater vehicle (AUV, its pitch attitude and stern plane deflections create forces and moments to achieve equilibrium in the vertical plane. If an AUV has a proportional controller only in its depth control loop, then different weights or centers of gravity will cause different steady-state depth errors at trimmed conditions. In general, a steady-state depth error can be eliminated by adding an integral controller in the depth control loop. However, an improper integrator may lead to a bad transient response, even though the steady-state depth error can finally be eliminated. To remove the steady-state depth error, this study proposes methods that adjust the depth command and add a switching integral controller in the depth control loop. Simulation results demonstrate that the steady-state depth error can be eliminated and the transient response can be improved.

  17. Reversal of alcohol-induced effects on response control due to changes in proprioceptive information processing.

    Science.gov (United States)

    Stock, Ann-Kathrin; Mückschel, Moritz; Beste, Christian

    2017-01-01

    Recent research has drawn interest to the effects of binge drinking on response selection. However, choosing an appropriate response is a complex endeavor that usually requires us to process and integrate several streams of information. One of them is proprioceptive information about the position of limbs. As to now, it has however remained elusive how binge drinking affects the processing of proprioceptive information during response selection and control in healthy individuals. We investigated this question using neurophysiological (EEG) techniques in a response selection task, where we manipulated proprioceptive information. The results show a reversal of alcohol-induced effects on response control due to changes in proprioceptive information processing. The most likely explanation for this finding is that proprioceptive information does not seem to be properly integrated in response selection processes during acute alcohol intoxication as found in binge drinking. The neurophysiological data suggest that processes related to the preparation and execution of the motor response, but not upstream processes related to conflict monitoring and spatial attentional orienting, underlie these binge drinking-dependent modulations. Taken together, the results show that even high doses of alcohol have very specific effects within the cascade of neurophysiological processes underlying response control and the integration of proprioceptive information during this process. © 2015 Society for the Study of Addiction.

  18. Digitally Controlled Point of Load Converter with Very Fast Transient Response

    DEFF Research Database (Denmark)

    Jakobsen, Lars Tønnes; Andersen, Michael Andreas E.

    2007-01-01

    three clock cycles from the time the A/D converter result is read by the control algorithm to the time the duty cycle command is updated. A typical POL converter has been built and the experimental results show that the transient response of the converter is very fast. The output voltage overshoot...... voltage mode control and very fast transient response. The DiSOM modulator is combined with a digital PID compensator algorithm is implemented in a hybrid CPLD/FPGA and is used to control a synchronous Buck converter, which is used in typical Point of Load applications. The computational time is only...

  19. Day-Ahead Scheduling Considering Demand Response as a Frequency Control Resource

    Directory of Open Access Journals (Sweden)

    Yu-Qing Bao

    2017-01-01

    Full Text Available The development of advanced metering technologies makes demand response (DR able to provide fast response services, e.g., primary frequency control. It is recognized that DR can contribute to the primary frequency control like thermal generators. This paper proposes a day-ahead scheduling method that considers DR as a frequency control resource, so that the DR resources can be dispatched properly with other resources. In the proposed method, the objective of frequency control is realized by defining a frequency limit equation under a supposed contingency. The frequency response model is used to model the dynamics of system frequency. The nonlinear frequency limit equation is transformed to a linear arithmetic equation by piecewise linearization, so that the problem can be solved by mixed integer linear programming (MILP. Finally, the proposed method is verified on numerical examples.

  20. Response control for the externally excited van der Pol oscillator with non-local feedback

    Science.gov (United States)

    Maccari, Attilio

    2012-02-01

    A non-local control force is introduced in such a way to obtain a third-order nonlinear differential equation (jerk dynamics) and to control nonlinear vibrations in an externally excited van der Pol oscillator. Two first-order nonlinear ordinary differential equations governing the modulation of the amplitude and the phase of solutions are derived and subsequently the performance of the control strategy is investigated. Excitation amplitude-response and frequency-response curves are shown. In certain cases when the excitation amplitude is very low an approximate analytic solution corresponding to a modulated two-period quasi-periodic motion can be obtained for the uncontrolled system. Uncontrolled and controlled systems are compared and the appropriate choices for the feedback gains are found in order to reduce the amplitude peak of the response and to exclude the possibility of quasi-periodic motion. Numerical simulation confirms the validity of the new method.

  1. Anxiety control and metacognitive beliefs mediate the relationship between inflated responsibility and obsessive compulsive symptoms.

    Science.gov (United States)

    Sassaroli, Sandra; Centorame, Francesco; Caselli, Gabriele; Favaretto, Ettore; Fiore, Francesca; Gallucci, Marcello; Sarracino, Diego; Ruggiero, Giovanni M; Spada, Marcantonio M; Rapee, Ronald M

    2015-08-30

    Research has indicated that beliefs about inflated responsibility, beliefs about perceived control over anxiety-related events and reactions (anxiety control) and metacognitive beliefs about the need to control thoughts are associated with obsessive compulsive symptoms. In the current study we tested a mediation model of the interactions between these variables in predicting obsessive compulsive symptoms. Thirty-seven individuals with obsessive compulsive disorder and 31 controls completed the following self-report instruments: the Responsibility Attitude Scale, the Anxiety Control Scale, the Beliefs about Need to Control Thoughts sub-scale of the Metacognitions Questionnaire 30, and the Padua Inventory. Mann-Whitney U tests revealed that participants in the clinical group scored significantly higher than those in the non-clinical group on all variables. In the mediation model we found that the relationship between beliefs about inflated responsibility and obsessive compulsive symptoms was fully mediated by anxiety control and beliefs about the need to control thoughts. These findings provide support for the significant role played by beliefs about control in predicting the severity of obsessive compulsive symptoms. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  2. Study on DFIG wind turbines control strategy for improving frequency response characteristics

    Science.gov (United States)

    Zhao, Dongmei; Wu, Di; Liu, Yanhua; Zhou, Zhiyu

    2012-01-01

    The active and reactive power decoupling control for the double-fed induction generator wind turbines(DFIG) does not play a positive role to the frequency response ability of power grid because it performs as the hidden inertia for the power grid. If we want to improve the transient frequency stability of the wind turbine when it is integrated with the system, we must ameliorate its frequency response characteristics. The inability of frequency control due to DFIG decoupling control could be overcome through releasing (or absorbing) a part of the kinetic energy stored in the rotor, so as to increase (or decrease) active power injected to the power system when the deviation of power system frequency appears. This paper discusses the mathematical model of the variable speed DFIG, including the aerodynamic model, pitch control system model, shaft model, generator model and inverter control model, and other key components, focusing on the mathematical model of the converters in rotor side and grid side. Based on the existing model of wind generator, the paper attaches the frequency control model on the platform of the simulation software DIgSILENT/PowerFactory. The simulation results show that the proposed control strategy can response quickly to transient frequency deviation and prove that wind farms can participate in the system frequency regulation to a certain extent. Finally, the result verifies the accuracy and plausibility of the inverter control model which attaches the frequency control module.

  3. Discovering Pediatric Asthma Phenotypes on the Basis of Response to Controller Medication Using Machine Learning.

    Science.gov (United States)

    Ross, Mindy K; Yoon, Jinsung; van der Schaar, Auke; van der Schaar, Mihaela

    2018-01-01

    Pediatric asthma has variable underlying inflammation and symptom control. Approaches to addressing this heterogeneity, such as clustering methods to find phenotypes and predict outcomes, have been investigated. However, clustering based on the relationship between treatment and clinical outcome has not been performed, and machine learning approaches for long-term outcome prediction in pediatric asthma have not been studied in depth. Our objectives were to use our novel machine learning algorithm, predictor pursuit (PP), to discover pediatric asthma phenotypes on the basis of asthma control in response to controller medications, to predict longitudinal asthma control among children with asthma, and to identify features associated with asthma control within each discovered pediatric phenotype. We applied PP to the Childhood Asthma Management Program study data (n = 1,019) to discover phenotypes on the basis of asthma control between assigned controller therapy groups (budesonide vs. nedocromil). We confirmed PP's ability to discover phenotypes using the Asthma Clinical Research Network/Childhood Asthma Research and Education network data. We next predicted children's asthma control over time and compared PP's performance with that of traditional prediction methods. Last, we identified clinical features most correlated with asthma control in the discovered phenotypes. Four phenotypes were discovered in both datasets: allergic not obese (A + /O - ), obese not allergic (A - /O + ), allergic and obese (A + /O + ), and not allergic not obese (A - /O - ). Of the children with well-controlled asthma in the Childhood Asthma Management Program dataset, we found more nonobese children treated with budesonide than with nedocromil (P = 0.015) and more obese children treated with nedocromil than with budesonide (P = 0.008). Within the obese group, more A + /O + children's asthma was well controlled with nedocromil than with budesonide (P = 0.022) or with placebo

  4. Dynamic response for thermal control and measurement and fast radiation thermometry

    Science.gov (United States)

    Shepard, R. L.; Cezairliyan, A.

    1989-01-01

    A preliminary evaluation was made by ORNL of a two-color ratio pyrometer (TCRP) for temperature control in the Modular Electromagnetic Levitation (MEL) experiment. A discussion was presented by Eric Spjut at the 1987 NASA Non-Contact Temperature Measurement Workshop (NASA Conf. Publ. 2503, pp. 182-213) in which he described the non-linear characteristics of the time response of TCPs. Researchers replicated his model and results and note that the non-linear response behavior is minimized for small temperature steps at high temperatures. They then used the predicted response in a model for a proportional or integral feedback controller and predicted the control characteristics for heating and cooling a 5-mm diameter sphere of niobium at high (1500 to 2750 K) temperatures. The analysis shows that for a slow (25-ms) time response for a commercial RCRP, overshoots of several hundred kelvins will result from a 100-K decrease in the setpoint, and temperature tracking errors of 14 to 45 K will occur for control temperature ramps of 1000K/s. For a fast (greater than 0.1 ms) time response, the overshoot and ramp response errors are largely eliminated.

  5. The Correlation of Nurses' job Burnout and Their Social Responsibility Considering the Role of Control Locus

    Directory of Open Access Journals (Sweden)

    Reyhane Izedi

    2016-07-01

    Full Text Available Background: Job burnout is an occupational hazard that reduces physical and mental energy of the staff. This study was aimed to investigate the relationship between the nurses' job burnout and their social responsibility considering the moderating role of control locus. Methods: In an analytical and cross-sectional study we used 3 valid questionnaires including Maslach burnout inventory, Dynson social responsibility and Rotter locus of control in 3 educational hospitals of Yazd, Iran. A total of 246 nurses contributed in the study. Data analysis was done through SPSS19. We used Pearson and Kendall correlation coefficient in data analysis. Findings: The mean scores of job burnout and social responsibility of studied group were 60.75 +8.37 and 71.84+15.47, respectively. Job burnout is negatively correlated with social responsibility statistically (r= -0.250 while locus of control acts as the moderator of this correlation. Conclusion: Our results suggest that creating a supportive work environment for nurses enhances their social responsibility trough affecting their level of job burnout. Also, the approved moderating role of control locus in the relationship of job burnout and social responsibility indicates that the personality traits can be considered as the appropriate criteria for entry to nursing schools.

  6. Dynamic response improvement of doubly fed induction generator-based wind farm using fuzzy logic controller

    Science.gov (United States)

    Hasanien, Hany M.; Al-Ammar, Essam A.

    2012-11-01

    Doubly fed induction generator (DFIG) based wind farm is today the most widely used concept. This paper presents dynamic response enhancement of DFIG based wind farm under remote fault conditions using the fuzzy logic controller. The goal of the work is to improve the dynamic response of DFIG based wind farm during and after the clearance of fault using the proposed controller. The stability of wind farm during and after the clearance of fault is investigated. The effectiveness of the fuzzy logic controller is then compared with that of a PI controller. The validity of the controllers in restoring the wind farms normal operation after the clearance of fault is illustrated by the simulation results which are carried out using MATLAB/SIMULINK. Simulation results are analyzed under different fault conditions.

  7. Lateral prefrontal cortex activity during cognitive control of emotion predicts response to social stress in schizophrenia

    Directory of Open Access Journals (Sweden)

    Laura M. Tully, PhD

    2014-01-01

    Full Text Available LPFC dysfunction is a well-established neural impairment in schizophrenia and is associated with worse symptoms. However, how LPFC activation influences symptoms is unclear. Previous findings in healthy individuals demonstrate that lateral prefrontal cortex (LPFC activation during cognitive control of emotional information predicts mood and behavior in response to interpersonal conflict, thus impairments in these processes may contribute to symptom exacerbation in schizophrenia. We investigated whether schizophrenia participants show LPFC deficits during cognitive control of emotional information, and whether these LPFC deficits prospectively predict changes in mood and symptoms following real-world interpersonal conflict. During fMRI, 23 individuals with schizophrenia or schizoaffective disorder and 24 healthy controls completed the Multi-Source Interference Task superimposed on neutral and negative pictures. Afterwards, schizophrenia participants completed a 21-day online daily-diary in which they rated the extent to which they experienced mood and schizophrenia-spectrum symptoms, as well as the occurrence and response to interpersonal conflict. Schizophrenia participants had lower dorsal LPFC activity (BA9 during cognitive control of task-irrelevant negative emotional information. Within schizophrenia participants, DLPFC activity during cognitive control of emotional information predicted changes in positive and negative mood on days following highly distressing interpersonal conflicts. Results have implications for understanding the specific role of LPFC in response to social stress in schizophrenia, and suggest that treatments targeting LPFC-mediated cognitive control of emotion could promote adaptive response to social stress in schizophrenia.

  8. Controlling Price-Responsive Heat Pumps for Overload Elimination in Distribution Systems

    DEFF Research Database (Denmark)

    Csetvei, Zsuzsa; Østergaard, Jacob; Nyeng, Preben

    2011-01-01

    This paper investigates the possibility of applying electric heat pumps with the control-by-price-concept in order to avoid overload in a local distribution system. The proposed control algorithm is based upon a centrally dispatched real-time market price, reflecting the state of a larger power...... system, and is extended with a local price control for overload elimination on the corresponding feeder. The paper presents the mathematical models of a two-node system with price-responsive heat pumps, the chosen methodology of the central price calculation, and the proposed local feedback control...

  9. Length Variation Effect of the Impulse Response Model of a Secondary Path in Embedded Control

    Directory of Open Access Journals (Sweden)

    Young-Sup Lee

    2016-01-01

    Full Text Available This study presents theoretical and experimental investigation on the length variation effect of the impulse response function (IRF for the secondary path model in active noise control using an embedded control board. A narrowband sweep noise was the disturbance for control in a duct with the length of 1800 mm. The IRF model incorporated into an adaptive feedforward filtered-x LMS (FxLMS algorithm was then analyzed in the variation of its length in terms of the mean square error, computation complexity, stability requirement, and attenuation performance before and after control. The FxLMS algorithm with various IRF lengths was implemented in a dSPACE DS1104 embedded control board for the real-time control. Finally the most reasonable IRF length, considering the computation complexity and performance, can be determined through the systematic investigation. The results in this study can be used for practical active noise control systems.

  10. Stability of adaptive cruise control systems taking account of vehicle response time and delay

    Energy Technology Data Exchange (ETDEWEB)

    Davis, L.C., E-mail: ldavis7@mailaps.org [10244 Normandy Dr., Plymouth, MI 48170 (United States)

    2012-08-20

    The region of string stability of a platoon of adaptive cruise control vehicles, taking into account the delay and response of the vehicle powertrain, is found. An upper bound on the explicit delay time as a function the first-order powertrain response time constant is determined. The system is characterized by a headway time constant, a sensitivity parameter, relative (to the vehicle immediately in front) velocity control, and delayed-velocity feedback or acceleration feedback. -- Highlights: ► I find the region of stability for a realistic adaptive cruise control system. ► Vehicle response time and explicit delay are included in the analysis. ► Delayed-feedback enlarges the parameter space that gives string stability.

  11. Animal Models for Investigating the Central Control of the Mammalian Diving Response

    Science.gov (United States)

    McCulloch, Paul Frederick

    2012-01-01

    Pioneering studies by Per Scholander indicated that the diving response consists of reflexly induced apnea, bradycardia and an alteration of blood flow that maintains perfusion of the heart and brain. More recently field physiological studies have shown that many marine animals can adjust cardiorespiratory aspects of their diving response depending upon the behavioral situation. This could suggest that the very labile heart rate during diving is under direct cortical control. However, the final control of autonomic nervous system functioning resides within the brainstem and not the cortex. Many physiologists regard the brain as a “black box” where important neuronal functioning occurs, but the complexity of such functioning leaves systematic investigation a daunting task. As a consequence the central control of the diving response has been under-investigated. Thus, to further advance the field of diving physiology by understanding its central neuronal control, it would be first necessary to understand the reflex circuitry that exists within the brainstem of diving animals. To do this will require an appropriate animal model. In this review, two animals, the muskrat and rat, will be offered as animal models to investigate the central aspects of the diving response. Firstly, although these rodents are not marine animals, natural histories indicate that both animals can and do exploit aquatic environments. Secondly, physiological recordings during natural and simulated diving indicate that both animals possess the same basic physiological responses to underwater submersion that occur in marine animals. Thirdly, the size and ease of housing of both animals makes them attractive laboratory research animals. Finally, the enormous amount of scientific literature regarding rodent brainstem autonomic control mechanisms, and the availability of brain atlases, makes these animals ideal choices to study the central control of the mammalian diving response. PMID:22661956

  12. Bilingualism increases neural response consistency and attentional control: evidence for sensory and cognitive coupling.

    Science.gov (United States)

    Krizman, Jennifer; Skoe, Erika; Marian, Viorica; Kraus, Nina

    2014-01-01

    Auditory processing is presumed to be influenced by cognitive processes - including attentional control - in a top-down manner. In bilinguals, activation of both languages during daily communication hones inhibitory skills, which subsequently bolster attentional control. We hypothesize that the heightened attentional demands of bilingual communication strengthens connections between cognitive (i.e., attentional control) and auditory processing, leading to greater across-trial consistency in the auditory evoked response (i.e., neural consistency) in bilinguals. To assess this, we collected passively-elicited auditory evoked responses to the syllable [da] in adolescent Spanish-English bilinguals and English monolinguals and separately obtained measures of attentional control and language ability. Bilinguals demonstrated enhanced attentional control and more consistent brainstem and cortical responses. In bilinguals, but not monolinguals, brainstem consistency tracked with language proficiency and attentional control. We interpret these enhancements in neural consistency as the outcome of strengthened attentional control that emerged from experience communicating in two languages. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Closed-loop step response for tuning PID-fractional-order-filter controllers.

    Science.gov (United States)

    Amoura, Karima; Mansouri, Rachid; Bettayeb, Maâmar; Al-Saggaf, Ubaid M

    2016-09-01

    Analytical methods are usually applied for tuning fractional controllers. The present paper proposes an empirical method for tuning a new type of fractional controller known as PID-Fractional-Order-Filter (FOF-PID). Indeed, the setpoint overshoot method, initially introduced by Shamsuzzoha and Skogestad, has been adapted for tuning FOF-PID controller. Based on simulations for a range of first order with time delay processes, correlations have been derived to obtain PID-FOF controller parameters similar to those obtained by the Internal Model Control (IMC) tuning rule. The setpoint overshoot method requires only one closed-loop step response experiment using a proportional controller (P-controller). To highlight the potential of this method, simulation results have been compared with those obtained with the IMC method as well as other pertinent techniques. Various case studies have also been considered. The comparison has revealed that the proposed tuning method performs as good as the IMC. Moreover, it might offer a number of advantages over the IMC tuning rule. For instance, the parameters of the fractional controller are directly obtained from the setpoint closed-loop response data without the need of any model of the plant to be controlled. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  14. Aggregation Control by Multi-stimuli-Responsive Poly( N-vinylamide) Derivatives in Aqueous System

    Science.gov (United States)

    Kawatani, Ryo; Nishiyama, Yasuhiro; Kamikubo, Hironari; Kakiuchi, Kiyomi; Ajiro, Hiroharu

    2017-07-01

    Thermal and photo responsive copolymer based on N-vinylamide backbone was designed. Methoxyethyl group and azobenzene were selected to improve hydrophilicity and photoresponsive moieties, respectively. The N-(methoxyethyl)- N-vinylformamide was synthesized and copolymerized with N-vinylformamide by free radical polymerization. In order to control the nanosized structures, poly( N-vinylformamide) derivatives bearing azobenzene at the N-position near to the vinyl polymer main chain were synthesized by polymer reaction with the poly( N-vinylformamide- co- N-(methoxyethyl)- N-vinylformamide) and azobenzene. Aggregation size of the multi-stimuli-responsive polymer was controlled by preparation of the hydrophobic interaction at around N-position.

  15. Response analysis of curved bridge with unseating failure control system under near-fault ground motions

    Science.gov (United States)

    Zuo, Ye; Sun, Guangjun; Li, Hongjing

    2018-01-01

    Under the action of near-fault ground motions, curved bridges are prone to pounding, local damage of bridge components and even unseating. A multi-scale fine finite element model of a typical three-span curved bridge is established by considering the elastic-plastic behavior of piers and pounding effect of adjacent girders. The nonlinear time-history method is used to study the seismic response of the curved bridge equipped with unseating failure control system under the action of near-fault ground motion. An in-depth analysis is carried to evaluate the control effect of the proposed unseating failure control system. The research results indicate that under the near-fault ground motion, the seismic response of the curved bridge is strong. The unseating failure control system perform effectively to reduce the pounding force of the adjacent girders and the probability of deck unseating.

  16. Psychotherapy Participants Show Increased Physiological Responsiveness to a Lab Stressor Relative to Matched Controls

    OpenAIRE

    Patrick R Steffen; Louise eFidalgo; Dominic eSchmuck; Yoko eTsui; Tracy eBrown

    2014-01-01

    Accumulating evidence indicates that psychotherapy participants show increased physiological responsiveness to stress. The purpose of the present study was to examine differences between individuals participating in outpatient psychotherapy and matched controls using an experimental design. Forty-two psychotherapy participants and forty-eight matched controls were assessed on cardiovascular and cortisol functioning at baseline, during the Trier Social Stress Test (TSST), and during a twenty-m...

  17. Transcription factors early growth response gene (Egr) 2 and 3 control inflammatory responses of tolerant T cells.

    Science.gov (United States)

    Omodho, Becky; Miao, Tizong; Symonds, Alistair L J; Singh, Randeep; Li, Suling; Wang, Ping

    2018-01-03

    Impaired proliferation and production of IL2 are the hallmarks of experimental T cell tolerance. However, in most autoimmune diseases, auto-reactive T cells do not display hyper proliferation, but inflammatory phenotypes. We have now demonstrated that the transcription factors Egr2 and 3 are important for the control of inflammatory cytokine production by tolerant T cells, but not for tolerance induction. In the absence of Egr2 and 3, T cell tolerance, as measured by impaired proliferation and production of IL2, can still be induced, but tolerant T cells produced high levels of inflammatory cytokines. Egr2 and 3 regulate expression of differentiation repressors and directly inhibit T-bet function in T cells. Indeed, decreased expression of differentiation repressors, such as Id3 and Tcf1, and increased expression of inflammatory transcription factors, such as RORγt and Bhlhe40 were found in Egr2/3 deficient T cells under tolerogenic conditions. In addition, T-bet was co-expressed with Egr2 in tolerant T cells and Egr2/3 defects leads to production of high levels of IFNγ in tolerant T cells. Our findings demonstrated that despite impaired proliferation and IL2 production, tolerant T cells can display inflammatory responses in response to antigen stimulation and this is controlled at least partly by Egr2 and 3. © 2017 The Authors. Immunity, Inflammation and Disease Published by John Wiley & Sons Ltd.

  18. Perceptions of industry responsibility and tobacco control policy by US tobacco company executives in trial testimony.

    Science.gov (United States)

    Chaiton, Michael; Ferrence, Roberta; LeGresley, Eric

    2006-12-01

    Trial testimony from the United States provides a unique opportunity to examine strategies of the American tobacco industry. This paper examines congruence between the arguments for tobacco control policy presented by representatives of the American tobacco industry at trial and the stages of responsibility associated with corporate social responsibility principles in other industries. Trial testimony collected and coded by the Deposition and Trial Testimony Archive (DATTA). All available testimony was gathered from representative senior staff from major tobacco companies: Brown & Williamson, Philip Morris, RJ Reynolds, and Liggett. Transcripts from each witness selected were collected and imported in text format into WinMax, a qualitative data program. The documents were searched for terms relating to tobacco control policies, and relevant terms were extracted. A hand search of the documents was also conducted by reading through the testimony. Inferred responsibility for various tobacco control policies (health information, second-hand smoking, youth smoking) was coded. The level of responsibility for tobacco control policy varied according to the maturity of the issue. For emerging issues, US tobacco company representatives expressed defensiveness while, for more mature issues, such as youth smoking, they showed increased willingness to deal with the issue. This response to social issues is consistent with corporate social responsibility strategies in other industries. While other industries use corporate social responsibility programmes to address social issues to protect their core business product, the fundamental social issue with tobacco is the product itself. As such, the corporate nature of tobacco companies is a structural obstacle to reducing harm caused by tobacco use.

  19. Frontal and limbic activation during inhibitory control predicts treatment response in major depressive disorder.

    Science.gov (United States)

    Langenecker, Scott A; Kennedy, Susan E; Guidotti, Leslie M; Briceno, Emily M; Own, Lawrence S; Hooven, Thomas; Young, Elizabeth A; Akil, Huda; Noll, Douglas C; Zubieta, Jon-Kar

    2007-12-01

    Inhibitory control or regulatory difficulties have been explored in major depressive disorder (MDD) but typically in the context of affectively salient information. Inhibitory control is addressed specifically by using a task devoid of affectively-laden stimuli, to disentangle the effects of altered affect and altered inhibitory processes in MDD. Twenty MDD and 22 control volunteer participants matched by age and gender completed a contextual inhibitory control task, the Parametric Go/No-go (PGNG) task during functional magnetic resonance imaging. The PGNG includes three levels of difficulty, a typical continuous performance task and two progressively more difficult versions including Go/No-go hit and rejection trials. After this test, 15 of 20 MDD patients completed a full 10-week treatment with s-citalopram. There was a significant interaction among response time (control subjects better), hits (control subjects better), and rejections (patients better). The MDD participants had greater activation compared with the control group in frontal and anterior temporal areas during correct rejections (inhibition). Activation during successful inhibitory events in bilateral inferior frontal and left amygdala, insula, and nucleus accumbens and during unsuccessful inhibition (commission errors) in rostral anterior cingulate predicted post-treatment improvement in depression symptoms. The imaging findings suggest that in MDD subjects, greater neural activation in frontal, limbic, and temporal regions during correct rejection of lures is necessary to achieve behavioral performance equivalent to control subjects. Greater activation in similar regions was further predictive of better treatment response in MDD.

  20. The vasovagal response during confrontation with blood-injury-injection stimuli: the role of perceived control.

    Science.gov (United States)

    Gilchrist, Philippe T; McGovern, Gillian E; Bekkouche, Nadine; Bacon, Simon L; Ditto, Blaine

    2015-04-01

    The vasovagal response (VVR) is a common medical problem, complicating and deterring people from various procedures. It is an unusual stress response given the widespread decreases in physiological activity. Nevertheless, VVR involves processes similar to those observed during episodes of strong emotions and pain. We hypothesized that heightened perceived control would reduce symptoms of VVR. Eighty-two young adults were randomly assigned to perceived control or no perceived control conditions during exposure to a stimulus video of a mitral valve surgery, known to trigger VVR in non-medical personnel. Perceived control was manipulated by allowing some participants to specify a break time, though all received equivalent breaks. Outcomes included subjective symptoms of VVR, anxiety, blood pressure, heart rate, and other measures derived from impedance cardiography. Compared to participants with perceived control, participants with no perceived control reported significantly more vasovagal symptoms and anxiety, and experienced lower stroke volume, cardiac output, and diastolic blood pressure. Participants who were more fearful of blood were more likely to benefit from perceived control in several measures. Perceived control appears to reduce vasovagal symptoms. Results are discussed in terms of cognition and emotion in VVR. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Cardiorespiratory and sensory responses to exercise in well-controlled asthmatics.

    Science.gov (United States)

    Cortés-Télles, Arturo; Torre-Bouscoulet, Luis; Mejía-Alfaro, Roberto; Silva-Cerón, Monica; Wilkie, Sabrina S; Guenette, Jordan A

    2015-01-01

    The purpose of this study was to evaluate detailed ventilatory, cardiovascular and sensory responses to cycle exercise in sedentary patients with well-controlled asthma and healthy controls. Subjects included sedentary patients meeting criteria for well-controlled asthma (n = 14), and healthy age- and activity-matched controls (n = 14). Visit 1 included screening for eligibility, medical history, anthropometrics, physical activity assessment, and pre- and post-bronchodilator spirometry. Visit 2 included spirometry and a symptom limited incremental cycle exercise test. Detailed ventilatory, cardiovascular and sensory responses were measured at rest and throughout exercise. Asthmatics and controls were well matched for age, body mass index and physical activity levels. Baseline forced expiratory volume in 1 second (FEV(1)) was similar between asthmatics and controls (98 ± 10 versus 95 ± 9% predicted, respectively, p > 0.05). No significant differences were observed between asthmatics and controls for maximal oxygen uptake (31.8 ± 5.6 versus 30.6 ± 5.9 ml/kg/min, respectively, p > 0.05) and power output (134 ± 35 versus 144 ± 32 W, respectively, p > 0.05). Minute ventilation (V(E)) relative to maximum voluntary ventilation (V(E)/MVV) was similar between groups at maximal exercise with no subjects showing evidence of ventilatory limitation. Asthmatics and controls achieved similar age-predicted maximum heart rates (92 ± 7 versus 93 ± 8% predicted, respectively, p > 0.05). Ratings of perceived breathing discomfort and leg fatigue were not different between groups throughout exercise. The results of this study indicate that sedentary patients with well-controlled asthma have preserved sensory and cardiorespiratory responses to exercise with no evidence of exercise impairment or ventilatory limitation.

  2. Differential cardiovascular and hypothalamic pituitary response to amphetamine in male pathological gamblers versus healthy controls.

    Science.gov (United States)

    Zack, Martin; Boileau, Isabelle; Payer, Doris; Chugani, Bindiya; Lobo, Daniela S; Houle, Sylvain; Wilson, Alan A; Warsh, Jerry J; Kish, Stephen J

    2015-09-01

    Cardiovascular and hypothalamic pituitary axis (HPA) disturbances have been observed in individuals who are pathological gamblers (PGs). These may partly derive from chronic exposure to gambling. Response to amphetamine (AMPH) may reveal such disturbances while controlling for differential conditioned responses to gambling in PGs vs healthy controls (HCs). This study assessed heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP) and plasma cortisol following oral AMPH (0.4 mg/kg) in male PGs (n=12) and HCs (n=11) who underwent a positron emission tomography (PET) scan. The Stop Signal Task enabled assessment of the link between physiological and behavioral dysregulation. Trait moderating effects were explored. The responses of PGs to AMPH differed from those of HCs on every index. PGs displayed persistent elevation in DBP and concomitant reduction in HR (i.e. baroreflex) compared to HCs beyond 90 min post-dose. PGs displayed deficits in cortisol compared to HCs that were partially reversed by AMPH. Impairment on the Stop Signal Task correlated positively with HR in controls, but negatively with HR in PGs, suggesting that strong initial and compensatory cardiac responses to a stimulant may each predict disinhibition. Extraversion predicted greater disinhibition in PGs. Noradrenergic disturbances may contribute to sensitized responses to stimulant challenge and disinhibition in PGs. © The Author(s) 2015.

  3. Evoked response audiometry in scrub typhus: prospective, randomised, case-control study.

    Science.gov (United States)

    Thakur, J S; Mohindroo, N K; Sharma, D R; Soni, K; Kaushal, S S

    2011-06-01

    To investigate the hypothesis of cochlear and retrocochlear damage in scrub typhus, using evoked response audiometry. Prospective, randomised, case-control study. The study included 25 patients with scrub typhus and 25 controls with other febrile illnesses not known to cause hearing loss. Controls were age- and sex-matched. All subjects underwent pure tone audiometry and evoked response audiometry before commencing treatment. Six patients presented with hearing loss, although a total of 23 patients had evidence of symmetrical high frequency loss on pure tone audiometry. Evoked response audiometry found significant prolongation of absolute latencies of wave I, III, V, and wave I-III interpeak latency. Two cases with normal hearing had increased interpeak latencies. These findings constitute level 3b evidence. Findings were suggestive of retrocochlear pathology in two cases with normal hearing. In other patients, high frequency hearing loss may have led to altered evoked response results. Although scrub typhus appears to cause middle ear cochlear and retrocochlear damage, the presence of such damage could not be fully confirmed by evoked response audiometry.

  4. Effect of controlled hyperventilation on the pressor response to laryngoscopy and tracheal intubation.

    Science.gov (United States)

    Talakoub, Reihanak; Khodayari, Azita; Saghaei, Mahmood

    2003-10-01

    Pressor response to laryngoscopy and tracheal intubation includes rises in blood pressure and heart rate. This response may be harmful in the presence of cerebral or myocardial diseases. Although different preventive measures have been developed the choice of the agent or method has not been defined clearly. Hypocapnia is commonly used in anesthesia practice for different indications. It depresses the cardiovascular system and lowers the cardiac output. This study investigated the effect of controlled hyperventilation on the pressor response to laryngoscopy and tracheal intubation in three groups of healthy adult patients with different levels of end tidal CO2. The blood pressure and heart rate were recorded during induction of general anesthesia before and after laryngoscopy and tracheal intubation. The pressor responses to laryngoscopy and tracheal intubation in hypocapnic and normocapnic groups were comparable. Moderate degrees of controlled hyperventilation caused relatively more fluctuation in blood pressure during induction of anesthesia. It can be concluded that controlled hyperventilation has no beneficial effect upon the pressor response to laryngoscopy and tracheal intubation.

  5. The response of social anxiety disorder patients to threat scenarios differs from that of healthy controls

    Directory of Open Access Journals (Sweden)

    S.C.V. Mesquita

    2011-12-01

    Full Text Available The objective of the present study was to evaluate the response of social anxiety disorder (SAD patients to threat scenarios. First-choice responses to 12 scenarios describing conspecific threatening situations and mean scores of defensive direction and defensive intensity dimensions were compared between 87 SAD patients free of medication and 87 matched healthy controls (HC. A significant gender difference in the first-choice responses was identified for seven scenarios among HCs but only for two scenarios among SAD patients. A significantly higher proportion of SAD patients chose "freezing" in response to "Bush" and "Noise" scenarios, whereas the most frequent response by HCs to these scenarios was "check out". SAD males chose "run away" and "yell" more often than healthy men in response to the scenarios "Park" and "Elevator", respectively. There was a positive correlation between the severity of symptoms and both defensive direction and defensive intensity dimensions. Factorial analysis confirmed the gradient of defensive reactions derived from animal studies. SAD patients chose more urgent defensive responses to threat scenarios, seeming to perceive them as more dangerous than HCs and tending to move away from the source of threat. This is consistent with the hypothesis that the physiopathology of anxiety disorders involves brain structures responsible for defensive behaviors.

  6. Single Cell Responses to Spatially Controlled Photosensitized Production of Extracellular Singlet Oxygen

    DEFF Research Database (Denmark)

    Pedersen, Brian Wett; Sinks, Louise E.; Breitenbach, Thomas

    2011-01-01

    The response of individual HeLa cells to extracellularly produced singlet oxygen was examined. The spatial domain of singlet oxygen production was controlled using the combination of a membrane-impermeable Pd porphyrin-dendrimer, which served as a photosensitizer, and a focused laser, which serve...

  7. Toll-like Receptor 7 Controls the Anti-Retroviral Germinal Center Response

    Science.gov (United States)

    Browne, Edward P.

    2011-01-01

    The development of vaccines that can enhance immunity to viral pathogens is an important goal. However, the innate molecular pathways that regulate the strength and quality of the immune response remain largely uncharacterized. To define the role of Toll-like receptor (TLR) signaling in control of a model retroviral pathogen, Friend virus (FV), I generated mice in which the TLR signaling adapter Myd88 was selectively deleted in dendritic cell (DC) or in B cell lineages. Deletion of Myd88 in DCs had little effect on immune control of FV, while B cell specific deletion of Myd88 caused a dramatic increase in viral infectious centers and a significantly reduced antibody response, indicating that B cell-intrinsic TLR signaling plays a crucial role, while TLR signaling in DCs is less important. I then identified the single-stranded RNA sensing protein TLR7 as being required for antibody-mediated control of FV by analyzing mice deficient in TLR7. Remarkably, B cells in infected TLR7-deficient mice upregulated CD69 and CD86 early in infection, but failed to develop into germinal center B cells. CD4 T cell responses were also attenuated in the absence of TLR7, but CD8 responses were TLR7 independent, suggesting the existence of additional pathways for detection of retroviral particles. Together these results demonstrate that the vertebrate immune system detects retroviruses in vivo via TLR7 and that this pathway regulates a key checkpoint controlling development of germinal center B cells. PMID:21998589

  8. Novel low-molecular-weight-gelator-based microcapsules with controllable morphology and temperature responsiveness.

    Science.gov (United States)

    Patel, Ashok R; Remijn, Caroline; Heussen, Patricia C M; den Adel, Ruud; Velikov, Krassimir P

    2013-02-04

    A new type of microcapsules with controllable morphology is presented. They are based on a low-molecular-weight gelator and can be switched from temperature-stable to temperature-responsive by simply modifying the preparation method. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Design and Co-simulation of Hierarchical Architecture for Demand Response Control and Coordination

    DEFF Research Database (Denmark)

    Bhattarai, Bishnu Prasad; Lévesque, Martin; Bak-Jensen, Birgitte

    2017-01-01

    Demand response (DR) plays a key role for optimum asset utilization and to avoid or delay the need of new infrastructure investment. However, coordinated execution of multiple DRs is desired to maximize the DR benefits. In this study, we propose a hierarchical DR architecture (HDRA) to control an...

  10. Sulfide response analysis for sulfide control using a pS electrode in sulfate reducing bioreactors

    NARCIS (Netherlands)

    Villa Gomez, D.K.; Cassidy, J.; Keesman, K.J.; Sampaio, R.M.; Lens, P.N.L.

    2014-01-01

    Step changes in the organic loading rate (OLR) through variations in the influent chemical oxygen demand (CODin) concentration or in the hydraulic retention time (HRT) at constant COD/SO4 2- ratio (0.67) were applied to create sulfide responses for the design of a sulfide control in sulfate reducing

  11. Motor Control Test Responses to Balance Perturbations in Adults with an Intellectual Disability

    Science.gov (United States)

    Hale, Leigh; Miller, Rebekah; Barach, Alice; Skinner, Margot; Gray, Andrew

    2009-01-01

    Background: The aims of this small exploratory study were to determine (1) whether adults with intellectual disability who had a recent history of falling had slower motor responses to postural perturbations than a sample of adults without disability when measured with the Motor Control Test (MCT) and (2) to identify any learning effects…

  12. Toll-like receptor 7 controls the anti-retroviral germinal center response.

    Directory of Open Access Journals (Sweden)

    Edward P Browne

    2011-10-01

    Full Text Available The development of vaccines that can enhance immunity to viral pathogens is an important goal. However, the innate molecular pathways that regulate the strength and quality of the immune response remain largely uncharacterized. To define the role of Toll-like receptor (TLR signaling in control of a model retroviral pathogen, Friend virus (FV, I generated mice in which the TLR signaling adapter Myd88 was selectively deleted in dendritic cell (DC or in B cell lineages. Deletion of Myd88 in DCs had little effect on immune control of FV, while B cell specific deletion of Myd88 caused a dramatic increase in viral infectious centers and a significantly reduced antibody response, indicating that B cell-intrinsic TLR signaling plays a crucial role, while TLR signaling in DCs is less important. I then identified the single-stranded RNA sensing protein TLR7 as being required for antibody-mediated control of FV by analyzing mice deficient in TLR7. Remarkably, B cells in infected TLR7-deficient mice upregulated CD69 and CD86 early in infection, but failed to develop into germinal center B cells. CD4 T cell responses were also attenuated in the absence of TLR7, but CD8 responses were TLR7 independent, suggesting the existence of additional pathways for detection of retroviral particles. Together these results demonstrate that the vertebrate immune system detects retroviruses in vivo via TLR7 and that this pathway regulates a key checkpoint controlling development of germinal center B cells.

  13. Ethical control and cultural change (in cultural dreams begin organizational responsibilities)

    NARCIS (Netherlands)

    S.J. Magala (Slawomir)

    2010-01-01

    textabstractEthical control is based on transparent access to the accounts of responsible behaviour on the part of individual and organizational actors. It is usually linked to the idea of a checkpoint: where celibate rules, no sexual interaction can be allowed. However, organizing and managing

  14. Responsibility for Teaching Pain Control in U.S. Dental Schools.

    Science.gov (United States)

    Smith, Peter B.; Campbell, Robert L.

    1993-01-01

    A national survey of 53 dental schools found most were not interested in developing a separate division or department of dental anesthesiology. Of those with a dentist anesthesiologist responsible for teaching pain control, all have or favor such a division. Less than one-third employ professionals limiting their practice to anesthesiology. (MSE)

  15. Dynamic response and control of a jet-transport aircraft encountering a single-axis vortex

    Science.gov (United States)

    Spilman, Darin R.

    1993-01-01

    The dynamic responses of a jet-transport aircraft to two types of single-axis wind vortex encounters are studied. Aircraft attitude, flight path angle, and aerodynamic angle excursions are analyzed and dominating dynamic forcing effects are identified for each encounter. A simple departure-preventing LQR controller is designed to demonstrate the benefits of using automatic control to reduce the wind vortex hazard. A Proportional-Integral-Filter controller structure successfully regulates the critical parameters, roll angle, phi, and sideslip angle, beta, for the two different vortex encounters considered in this study.

  16. Dex/CRH test cortisol response in outpatients with major depression and matched healthy controls.

    Science.gov (United States)

    Carpenter, Linda L; Ross, Nicole S; Tyrka, Audrey R; Anderson, George M; Kelly, Megan; Price, Lawrence H

    2009-09-01

    The dexamethasone/corticotropin releasing hormone (Dex/CRH) test has been proposed as a potential tool for identifying endophenotypes relevant to mood disorders. An exaggerated cortisol response to the test during major depressive episodes has been demonstrated for inpatients with melancholic or psychotic features. A diminished hormone response has been observed in chronically depressed outpatients. Following a battery of self-report and interview assessments, 68 adults completed the Dex/CRH test. Thirty-four met structured interview criteria for current major depressive disorder and 34 age- and sex-matched control subjects had no current or lifetime DSM-IV depressive disorder. Effect of diagnosis on cortisol response to the Dex/CRH test was examined in a repeated measures general linear model. The matched groups were equivalent with regard to childhood adversity. Cortisol response to the Dex/CRH test among subjects with current MDD was not significantly different from that seen in matched healthy controls. Independent of diagnosis, an exploratory analysis showed a trend-level association between maltreatment history and diminished cortisol response; no interactive effects with depression diagnosis were detected. The results do not support the hypothesis that elevated cortisol response to the Dex/CRH test represents a marker for major depressive episodes.

  17. Hydrophilic magnetic nanoclusters with thermo-responsive properties and their drug controlled release

    Energy Technology Data Exchange (ETDEWEB)

    Meerod, Siraprapa [Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Naresuan University, Phitsanulok 65000 (Thailand); Rutnakornpituk, Boonjira; Wichai, Uthai [Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Naresuan University, Phitsanulok 65000 (Thailand); Center of Excellence in Biomaterials, Faculty of Science, Naresuan University, Phitsanulok 65000 Thailand (Thailand); Rutnakornpituk, Metha, E-mail: methar@nu.ac.th [Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Naresuan University, Phitsanulok 65000 (Thailand); Center of Excellence in Biomaterials, Faculty of Science, Naresuan University, Phitsanulok 65000 Thailand (Thailand)

    2015-10-15

    Synthesis and drug controlled release properties of thermo-responsive magnetic nanoclusters grafted with poly(N-isopropylacrylamide) (poly(NIPAAm)) and poly(NIPAAm-co-poly(ethylene glycol) methyl ether methacrylate) (PEGMA) copolymers were described. These magnetic nanoclusters were synthesized via an in situ radical polymerization in the presence of acrylamide-grafted magnetic nanoparticles (MNPs). Poly(NIPAAm) provided thermo-responsive properties, while PEGMA played a role in good water dispersibility to the nanoclusters. The ratios of PEGMA to NIPAAm in the (co)polymerization in the presence of the MNPs were fine-tuned such that the nanoclusters with good water dispersibility, good magnetic sensitivity and thermo responsiveness were obtained. The size of the nanoclusters was in the range of 50–100 nm in diameter with about 100–200 particles/cluster. The nanoclusters were well dispersible in water at room temperature and can be suddenly agglomerated when temperature was increased beyond the lower critical solution temperature (LCST) (32 °C). The release behavior of an indomethacin model drug from the nanoclusters was also investigated. These novel magnetic nanoclusters with good dispersibility in water and reversible thermo-responsive properties might be good candidates for the targeting drug controlled release applications. - Highlights: • Nanoclusters with good water dispersibility and magnetic response were prepared. • They were grafted with thermo-responsive poly(NIPAAm) and/or poly(PEGMA). • Poly(NIPAAm) provided thermo-responsive properties to the nanoclusters. • Poly(PEGMA) provided good water dispersibilityto the nanoclusters. • Accelerated and controllable releases of a drug from the nanoclusters were shown.

  18. Metabolomics of Ramadan fasting: an opportunity for the controlled study of physiological responses to food intake

    Science.gov (United States)

    2014-01-01

    High-throughput screening techniques that analyze the metabolic endpoints of biological processes can identify the contributions of genetic predisposition and environmental factors to the development of common diseases. Studies applying controlled physiological challenges can reveal dysregulation in metabolic responses that may be predictive for or associated with these diseases. However, large-scale epidemiological studies with well controlled physiological challenge conditions, such as extended fasting periods and defined food intake, pose logistic challenges. Culturally and religiously motivated behavioral patterns of life style changes provide a natural setting that can be used to enroll a large number of study volunteers. Here we report a proof of principle study conducted within a Muslim community, showing that a metabolomics study during the Holy Month of Ramadan can provide a unique opportunity to explore the pre-prandial and postprandial response of human metabolism to nutritional challenges. Up to five blood samples were obtained from eleven healthy male volunteers, taken directly before and two hours after consumption of a controlled meal in the evening on days 7 and 26 of Ramadan, and after an over-night fast several weeks after Ramadan. The observed increases in glucose, insulin and lactate levels at the postprandial time point confirm the expected physiological response to food intake. Targeted metabolomics further revealed significant and physiologically plausible responses to food intake by an increase in bile acid and amino acid levels and a decrease in long-chain acyl-carnitine and polyamine levels. A decrease in the concentrations of a number of phospholipids between samples taken on days 7 and 26 of Ramadan shows that the long-term response to extended fasting may differ from the response to short-term fasting. The present study design is scalable to larger populations and may be extended to the study of the metabolic response in defined patient

  19. Metabolomics of Ramadan fasting: an opportunity for the controlled study of physiological responses to food intake.

    Science.gov (United States)

    Mathew, Sweety; Krug, Susanne; Skurk, Thomas; Halama, Anna; Stank, Antonia; Artati, Anna; Prehn, Cornelia; Malek, Joel A; Kastenmüller, Gabi; Römisch-Margl, Werner; Adamski, Jerzy; Hauner, Hans; Suhre, Karsten

    2014-06-06

    High-throughput screening techniques that analyze the metabolic endpoints of biological processes can identify the contributions of genetic predisposition and environmental factors to the development of common diseases. Studies applying controlled physiological challenges can reveal dysregulation in metabolic responses that may be predictive for or associated with these diseases. However, large-scale epidemiological studies with well controlled physiological challenge conditions, such as extended fasting periods and defined food intake, pose logistic challenges. Culturally and religiously motivated behavioral patterns of life style changes provide a natural setting that can be used to enroll a large number of study volunteers. Here we report a proof of principle study conducted within a Muslim community, showing that a metabolomics study during the Holy Month of Ramadan can provide a unique opportunity to explore the pre-prandial and postprandial response of human metabolism to nutritional challenges. Up to five blood samples were obtained from eleven healthy male volunteers, taken directly before and two hours after consumption of a controlled meal in the evening on days 7 and 26 of Ramadan, and after an over-night fast several weeks after Ramadan. The observed increases in glucose, insulin and lactate levels at the postprandial time point confirm the expected physiological response to food intake. Targeted metabolomics further revealed significant and physiologically plausible responses to food intake by an increase in bile acid and amino acid levels and a decrease in long-chain acyl-carnitine and polyamine levels. A decrease in the concentrations of a number of phospholipids between samples taken on days 7 and 26 of Ramadan shows that the long-term response to extended fasting may differ from the response to short-term fasting. The present study design is scalable to larger populations and may be extended to the study of the metabolic response in defined patient

  20. Hierarchical control framework for integrated coordination between distributed energy resources and demand response

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Di; Lian, Jianming; Sun, Yannan; Yang, Tao; Hansen, Jacob

    2017-09-01

    Demand response is representing a significant but largely untapped resource that can greatly enhance the flexibility and reliability of power systems. In this paper, a hierarchical control framework is proposed to facilitate the integrated coordination between distributed energy resources and demand response. The proposed framework consists of coordination and device layers. In the coordination layer, various resource aggregations are optimally coordinated in a distributed manner to achieve the system-level objectives. In the device layer, individual resources are controlled in real time to follow the optimal power generation or consumption dispatched from the coordination layer. For the purpose of practical applications, a method is presented to determine the utility functions of controllable loads by taking into account the real-time load dynamics and the preferences of individual customers. The effectiveness of the proposed framework is validated by detailed simulation studies.

  1. The role of implicit affective responses and trait self-control in ego resource management.

    Science.gov (United States)

    Buczny, Jacek; Layton, Rebekah L; Muraven, Mark

    Exertion of self-control requires reliance on ego resources. Impaired performance typically results once those resources have been depleted by previous use. Yet the mechanism behind the depletion processes is little understood. Beliefs, motivation, and physiological changes have been implicated, yet the source behind these remains unknown. We propose that implicit may form the fundamental building blocks that these processes rely upon to operate. Implicit affective responses to energy may trigger management of ego resources after depletion. Findings suggest that inhibitory trait self-control may interact with the depletion effect, indicating the importance of taking individual differences in chronic availability of ego-resources into account. After depletion, individuals high in trait self-control may be less motivated to conserve remaining resources than those low in self-control. This mechanism may also help explain the conservation of resources observed when expecting multiple tasks requiring self-control.

  2. Linear response theory and optimal control for a molecular system under non-equilibrium conditions

    Science.gov (United States)

    Wang, Han; Hartmann, Carsten; Schütte, Christof

    2013-12-01

    In this paper, we propose a straightforward generalisation of the linear response theory on a finite time-horizon to systems in non-equilibrium that are subject to external forcing. We briefly revisit the standard linear response result for equilibrium systems, where we consider Langevin dynamics as a special case, and then give an alternative derivation using a change-of-measure argument that does not rely on any stationarity or reversibility assumption. This procedure easily enables us to calculate the second-order correction to the linear response formula (which may or may not be useful in practice). Furthermore, we outline how the novel non-equilibrium linear response formula can be used to compute optimal controls of molecular systems for cases in which one wants to steer the system to maximise a certain target expectation value. We illustrate our approach with simple numerical examples.

  3. What roles do regulatory T cells play in the control of the adaptive immune response?

    Science.gov (United States)

    Cohn, Melvin

    2008-09-01

    The immune system, like many systems responsive to specific stimuli, requires feedback regulation. The key regulatory element determining antigen-specific responsiveness is the effector T helper. As the response tends to overshoot, a feedback control of the magnitude of the response is critical to avoid immunopathology. This is the proposed role of the effector T suppressor (T(s)). The reasons for this interpretation of the data are discussed as are the reasons that the competing postulate is ruled out, namely that T(s) function in determining the self-non-self-discrimination. The regulatory T cell family consists of two lineages, T helpers and T(s). Differentiated derivatives of the T helper lineage drive the expression and amplification of specific classes of defensive effector cells. T(s) feedback to limit the magnitude of the process so that debilitating immunopathology is acceptably infrequent.

  4. PTP1B triggers integrin-mediated repression of myosin activity and modulates cell contractility

    Directory of Open Access Journals (Sweden)

    Ana E. González Wusener

    2016-01-01

    Full Text Available Cell contractility and migration by integrins depends on precise regulation of protein tyrosine kinase and Rho-family GTPase activities in specific spatiotemporal patterns. Here we show that protein tyrosine phosphatase PTP1B cooperates with β3 integrin to activate the Src/FAK signalling pathway which represses RhoA-myosin-dependent contractility. Using PTP1B null (KO cells and PTP1B reconstituted (WT cells, we determined that some early steps following cell adhesion to fibronectin and vitronectin occurred robustly in WT cells, including aggregation of β3 integrins and adaptor proteins, and activation of Src/FAK-dependent signalling at small puncta in a lamellipodium. However, these events were significantly impaired in KO cells. We established that cytoskeletal strain and cell contractility was highly enhanced at the periphery of KO cells compared to WT cells. Inhibition of the Src/FAK signalling pathway or expression of constitutive active RhoA in WT cells induced a KO cell phenotype. Conversely, expression of constitutive active Src or myosin inhibition in KO cells restored the WT phenotype. We propose that this novel function of PTP1B stimulates permissive conditions for adhesion and lamellipodium assembly at the protruding edge during cell spreading and migration.

  5. The cancer glycocalyx mechanically primes integrin-mediated growth and survival

    OpenAIRE

    Paszek, Matthew J.; DuFort, Christopher C.; Rossier, Olivier; Bainer, Russell; Mouw, Janna K.; Godula, Kamil; Hudak, Jason E.; Lakins, Jonathon N.; Wijekoon, Amanda C.; Cassereau, Luke; Rubashkin, Matthew G.; Magbanua, Mark J.; Thorn, Kurt S.; Davidson, Michael W.; Rugo, Hope S.

    2014-01-01

    Malignancy is associated with altered expression of glycans and glycoproteins that contribute to the cellular glycocalyx. We constructed a glycoprotein expression signature, which revealed that metastatic tumours upregulate expression of bulky glycoproteins. A computational model predicted that these glycoproteins would influence transmembrane receptor spatial organization and function. We tested this prediction by investigating whether bulky glycoproteins in the glycocalyx promote a tumour p...

  6. The cancer glycocalyx mechanically primes integrin-mediated growth and survival.

    Science.gov (United States)

    Paszek, Matthew J; DuFort, Christopher C; Rossier, Olivier; Bainer, Russell; Mouw, Janna K; Godula, Kamil; Hudak, Jason E; Lakins, Jonathon N; Wijekoon, Amanda C; Cassereau, Luke; Rubashkin, Matthew G; Magbanua, Mark J; Thorn, Kurt S; Davidson, Michael W; Rugo, Hope S; Park, John W; Hammer, Daniel A; Giannone, Grégory; Bertozzi, Carolyn R; Weaver, Valerie M

    2014-07-17

    Malignancy is associated with altered expression of glycans and glycoproteins that contribute to the cellular glycocalyx. We constructed a glycoprotein expression signature, which revealed that metastatic tumours upregulate expression of bulky glycoproteins. A computational model predicted that these glycoproteins would influence transmembrane receptor spatial organization and function. We tested this prediction by investigating whether bulky glycoproteins in the glycocalyx promote a tumour phenotype in human cells by increasing integrin adhesion and signalling. Our data revealed that a bulky glycocalyx facilitates integrin clustering by funnelling active integrins into adhesions and altering integrin state by applying tension to matrix-bound integrins, independent of actomyosin contractility. Expression of large tumour-associated glycoproteins in non-transformed mammary cells promoted focal adhesion assembly and facilitated integrin-dependent growth factor signalling to support cell growth and survival. Clinical studies revealed that large glycoproteins are abundantly expressed on circulating tumour cells from patients with advanced disease. Thus, a bulky glycocalyx is a feature of tumour cells that could foster metastasis by mechanically enhancing cell-surface receptor function.

  7. The cancer glycocalyx mechanically primes integrin-mediated growth and survival

    Science.gov (United States)

    Paszek, Matthew J.; DuFort, Christopher C.; Rossier, Olivier; Bainer, Russell; Mouw, Janna K.; Godula, Kamil; Hudak, Jason E.; Lakins, Jonathon N.; Wijekoon, Amanda C.; Cassereau, Luke; Rubashkin, Matthew G.; Magbanua, Mark J.; Thorn, Kurt S.; Davidson, Michael W.; Rugo, Hope S.; Park, John W.; Hammer, Daniel A.; Giannone, Grégory; Bertozzi, Carolyn R.; Weaver, Valerie M.

    2015-01-01

    Malignancy is associated with altered expression of glycans and glycoproteins that contribute to the cellular glycocalyx. We constructed a glycoprotein expression signature, which revealed that metastatic tumours upregulate expression of bulky glycoproteins. A computational model predicted that these glycoproteins would influence transmembrane receptor spatial organization and function. We tested this prediction by investigating whether bulky glycoproteins in the glycocalyx promote a tumour phenotype in human cells by increasing integrin adhesion and signalling. Our data revealed that a bulky glycocalyx facilitates integrin clustering by funnelling active integrins into adhesions and altering integrin state by applying tension to matrix-bound integrins, independent of actomyosin contractility. Expression of large tumour-associated glycoproteins in non-transformed mammary cells promoted focal adhesion assembly and facilitated integrin-dependent growth factor signalling to support cell growth and survival. Clinical studies revealed that large glycoproteins are abundantly expressed on circulating tumour cells from patients with advanced disease. Thus, a bulky glycocalyx is a feature of tumour cells that could foster metastasis by mechanically enhancing cell-surface receptor function. PMID:25030168

  8. Integrin-mediated mechanotransduction pathway of low-intensity continuous ultrasound in human chondrocytes.

    Science.gov (United States)

    Whitney, Nicholas P; Lamb, Allyson C; Louw, Tobias M; Subramanian, Anuradha

    2012-10-01

    Chondrocytes are mechanosensitive cells that require mechanical stimulation for proper growth and function in in vitro culture systems. Ultrasound (US) has emerged as a technique to deliver mechanical stress; however, the intracellular signaling components of the mechanotransduction pathways that transmit the extracellular mechanical stimulus to gene regulatory mechanisms are not fully defined. We evaluated a possible integrin/mitogen-activated protein kinase (MAPK) mechanotransduction pathway using Western blotting with antibodies targeting specific phosphorylation sites on intracellular signaling proteins. US stimulation of chondrocytes induced phosphorylation of focal adhesion kinase (FAK), Src, p130 Crk-associated substrate (p130Cas), CrkII and extracellular-regulated kinase (Erk). Furthermore, pre-incubation with inhibitors of integrin receptors, Src and MAPK/Erk kinase (MEK) reduced US-induced Erk phosphorylation levels, indicating integrins and Src are upstream of Erk in an US-mediated mechanotransduction pathway. These findings suggest US signals through integrin receptors to the MAPK/Erk pathway via a mechanotransduction pathway involving FAK, Src, p130Cas and CrkII. Published by Elsevier Inc.

  9. Extracellular Alix regulates integrin-mediated cell adhesions and extracellular matrix assembly

    OpenAIRE

    Pan, Shujuan; Wang, Ruoning; Zhou, Xi; Corvera, Joe; Kloc, Malgorzata; Sifers, Richard; Gallick, Gary E; Lin, Sue-Hwa; Kuang, Jian

    2008-01-01

    Alix (ALG-2-interacting protein X), a cytoplasmic adaptor protein involved in endosomal sorting and actin cytoskeleton assembly, is required for the maintenance of fibroblast morphology. As Alix has sequence similarity to adhesin in Entamoeba histolytica, and we observed that Alix is secreted, we determined whether extracellular Alix affects fibroblast morphology. Here, we demonstrate that secreted Alix is deposited on the substratum of non-immortalized WI38 fibroblasts. Antibody binding to e...

  10. Integrin-mediated internalization of Staphylococcus aureus does not require vinculin

    National Research Council Canada - National Science Library

    Borisova, Marina; Shi, Yong; Buntru, Alexander; Wörner, Susanne; Ziegler, Wolfgang H; Hauck, Christof R

    2013-01-01

    .... As reorganization of the actin cytoskeleton is critical for bacterial entry, we investigated whether vinculin, an essential protein linking integrins with the actin cytoskeleton, may contribute...

  11. Integrin-mediated host cell invasion by type 1-piliated uropathogenic Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Danelle S Eto

    2007-07-01

    Full Text Available Uropathogenic Escherichia coli (UPEC, the primary causative agent of urinary tract infections, typically express filamentous adhesive organelles called type 1 pili that mediate both bacterial attachment to and invasion of bladder urothelial cells. Several host proteins have previously been identified as receptors for type 1 pili, but none have been conclusively shown to promote UPEC entry into host bladder cells. Using overlay assays with FimH, the purified type 1 pilus adhesin, and mass spectroscopy, we have identified beta1 and alpha3 integrins as key host receptors for UPEC. FimH recognizes N-linked oligosaccharides on these receptors, which are expressed throughout the urothelium. In a bladder cell culture system, beta1 and alpha3 integrin receptors co-localize with invading type 1-piliated bacteria and F-actin. FimH-mediated bacterial invasion of host bladder cells is inhibited by beta1 and alpha3 integrin-specific antibodies and by disruption of the beta1 integrin gene in the GD25 fibroblast cell line. Phosphorylation site mutations within the cytoplasmic tail of beta1 integrin that alter integrin signaling also variably affect UPEC entry into host cells, by either attenuating or boosting invasion frequencies. Furthermore, focal adhesion and Src family kinases, which propagate integrin-linked signaling and downstream cytoskeletal rearrangements, are shown to be required for FimH-dependent bacterial invasion of target host cells. Cumulatively, these results indicate that beta1 and alpha3 integrins are functionally important receptors for type 1 pili-expressing bacteria within the urinary tract and possibly at other sites within the host.

  12. The Transcription Factor IRF8 Activates Integrin-mediated TGFβ Signaling and Promotes Neuroinflammation

    Science.gov (United States)

    Yoshida, Yuko; Yoshimi, Ryusuke; Yoshii, Hiroaki; Kim, Daniel; Dey, Anup; Xiong, Huabao; Munasinghe, Jeeva; Yazawa, Itaru; O’Donovan, Michael J.; Maximova, Olga A.; Sharma, Suveena; Zhu, Jinfang; Wang, Hongsheng; Morse, Herbert C.; Ozato, Keiko

    2014-01-01

    SUMMARY Recent epidemiological studies have identified interferon regulatory factor 8 (IRF8) as a susceptibility factor for multiple sclerosis (MS). However, how IRF8 influences the neuroinflammatory disease has remained unknown. By studying the role of IRF8 in experimental autoimmune encephalomyelitis (EAE), a mouse model of MS, we found that Irf8−/− mice are resistant to EAE. Furthermore, expression of IRF8 in antigen presenting cells (APCs, such as macrophages, dendritic cells and microglia), but not in T cells, facilitated disease onset and progression through multiple pathways. IRF8 enhanced αvβ8 integrin expression in APCs and activated TGFβ signaling leading to T helper 17 (Th17) cell differentiation. IRF8 induced a cytokine milieu that favored growth and maintenance of Th1 and Th17 cells, by stimulating interleukin-12 (IL12) and IL23 production, but inhibiting IL27 during EAE. Finally, IRF8 activated microglia and exacerbated neuroinflammation. Together, this work provides mechanistic bases by which IRF8 contributes to the pathogenesis of MS. PMID:24485804

  13. Lebestatin, a disintegrin from Macrovipera venom, inhibits integrin-mediated cell adhesion, migration and angiogenesis.

    Science.gov (United States)

    Olfa, Kallech-Ziri; José, Luis; Salma, Daoud; Amine, Bazaa; Najet, Srairi Abid; Nicolas, Andreotti; Maxime, Lehmann; Raoudha, Zouari; Kamel, Mabrouk; Jacques, Marvaldi; Jean-Marc, Sabatier; Mohamed, El Ayeb; Naziha, Marrakchi

    2005-12-01

    Lebestatin, a new member of the lysine-threonine-serine (KTS)-disintegrin family, was purified to homogeneity from Tunisian snake (Macrovipera lebetina) venom. It is a single-chain polypeptide composed of 41 amino acids. The amino-acid sequence of lebestatin shows that it displays a pattern of cysteines similar to other short disintegrins, but contains the sequence KTS rather than RGD in its integrin-binding loop. Lebestatin presents a high homology with obtustatin and viperistatin. Lebestatin interacts specifically with the alpha1beta1 integrin. It was thus able to inhibit both adhesion and migration of PC12 and alpha1beta1 integrin-expressing CHO cells (CHO-alpha1) to type I and IV collagens. This disintegrin also affected adhesion and migration of endothelial cells and exhibited an anti-angiogenic effect in vivo when using the 8-day-old embryo chick chorioallantoic membrane model.

  14. Controllability modulates the anticipatory response in the human ventromedial prefrontal cortex

    Directory of Open Access Journals (Sweden)

    Deborah Lucille Kerr

    2012-12-01

    Full Text Available Research has consistently shown that control is critical to psychological functioning, with perceived lack of control considered to play a crucial role in the manifestation of symptoms in psychiatric disorders. In a model of behavioral control based on nonhuman animal work, Maier and colleagues posited that the presence of control activates areas of the ventromedial prefrontal cortex (vmPFC, which in turn inhibit the normative stress response in the dorsal raphe nucleus and amygdala. To test Maier’s model in humans, we investigated the effects of control over potent aversive stimuli by presenting video clips of snakes to 21 snake phobics who were otherwise healthy with no comorbid psychopathologies. Based on prior research documenting that disrupted neural processing during the anticipation of adverse events can be influenced by different forms of cognitive processing such as perceptions of control, analyses focused on the anticipatory activity preceding the videos. We found that phobics exhibited greater vmPFC activity during the anticipation of snake videos when they had control over whether the videos were presented as compared to when they had no control over the presentation of the videos. In addition, observed functional connectivity between the vmPFC and the amygdala is consistent with previous work documenting vmPFC inhibition of the amygdala. Our results provide evidence to support the extension of Maier’s model of behavioral control to include anticipatory function in humans.

  15. Membrane fluidity controls redox-regulated cold stress responses in cyanobacteria.

    Science.gov (United States)

    Maksimov, Eugene G; Mironov, Kirill S; Trofimova, Marina S; Nechaeva, Natalya L; Todorenko, Daria A; Klementiev, Konstantin E; Tsoraev, Georgy V; Tyutyaev, Eugene V; Zorina, Anna A; Feduraev, Pavel V; Allakhverdiev, Suleyman I; Paschenko, Vladimir Z; Los, Dmitry A

    2017-09-01

    Membrane fluidity is the important regulator of cellular responses to changing ambient temperature. Bacteria perceive cold by the transmembrane histidine kinases that sense changes in thickness of the cytoplasmic membrane due to its rigidification. In the cyanobacterium Synechocystis, about a half of cold-responsive genes is controlled by the light-dependent transmembrane histidine kinase Hik33, which also partially controls the responses to osmotic, salt, and oxidative stress. This implies the existence of some universal, but yet unknown signal that triggers adaptive gene expression in response to various stressors. Here we selectively probed the components of photosynthetic machinery and functionally characterized the thermodynamics of cyanobacterial photosynthetic membranes with genetically altered fluidity. We show that the rate of oxidation of the quinone pool (PQ), which interacts with both photosynthetic and respiratory electron transport chains, depends on membrane fluidity. Inhibitor-induced stimulation of redox changes in PQ triggers cold-induced gene expression. Thus, the fluidity-dependent changes in the redox state of PQ may universally trigger cellular responses to stressors that affect membrane properties.

  16. Subjective and Physiological Responses to Music Stimuli Controlled Over Activity and Preference.

    Science.gov (United States)

    Iwanaga; Moroki

    1999-01-01

    Results of physiological responses to music are inconclusive considering results of several studies, probably due to the insufficient control of the musical stimuli. The present study aimed to examine the effects of music type and preference on subjective and physiological responses using controlled stimuli by subjects' evaluations for music activity and preference. Subjects were 47 undergraduate students selected from a pool of 145 undergraduates. Results of evaluations of music activity and music preference for musical stimuli in preliminary research determined participation in the study. The music used in this study included the 4th movement of Tchaikovsky's Symphony No. 4 as an excitative piece and the 3rd movement of Mahler's Symphony No. 6 as a sedative one. The excitative music aroused feelings of vigor and tension more than did the sedative one, while sedative music eased tension. Favorite music, regardless of music type, lowered subjective tension. Physiological responses (heart rate, respiration, and blood pressure) were greater during excitative music than during sedative music. Music preference did not, however, affect physiological responses. These results indicate that the dominant factor affecting emotional response was music type but not preference.

  17. Parametric Control on Fractional-Order Response for Lü Chaotic System

    KAUST Repository

    Moaddy, K

    2013-04-10

    This paper discusses the influence of the fractional order parameter on conventional chaotic systems. These fractional-order parameters increase the system degree of freedom allowing it to enter new domains and thus it can be used as a control for such dynamical systems. This paper investigates the behaviour of the equally-fractional-order Lü chaotic system when changing the fractional-order parameter and determines the fractional-order ranges for chaotic behaviour. Five different parameter values and six fractional-order cases are discussed through this paper. Unlike the conventional parameters, as the fractional-order increases the system response begins with stability, passing by chaotic behaviour then reaches periodic response. As the system parameter α increases, a shift in the fractional order is required to maintain chaotic response.Therefore, the range of chaotic response can be expanded or minimized by controlling the fractional-order parameter. The non-standard finite difference method is used to solve the fractional-order Lü chaotic system numerically to validate these responses.

  18. Action video games and improved attentional control: Disentangling selection- and response-based processes.

    Science.gov (United States)

    Chisholm, Joseph D; Kingstone, Alan

    2015-10-01

    Research has demonstrated that experience with action video games is associated with improvements in a host of cognitive tasks. Evidence from paradigms that assess aspects of attention has suggested that action video game players (AVGPs) possess greater control over the allocation of attentional resources than do non-video-game players (NVGPs). Using a compound search task that teased apart selection- and response-based processes (Duncan, 1985), we required participants to perform an oculomotor capture task in which they made saccades to a uniquely colored target (selection-based process) and then produced a manual directional response based on information within the target (response-based process). We replicated the finding that AVGPs are less susceptible to attentional distraction and, critically, revealed that AVGPs outperform NVGPs on both selection-based and response-based processes. These results not only are consistent with the improved-attentional-control account of AVGP benefits, but they suggest that the benefit of action video game playing extends across the full breadth of attention-mediated stimulus-response processes that impact human performance.

  19. Sulfide response analysis for sulfide control using a pS electrode in sulfate reducing bioreactors.

    Science.gov (United States)

    Villa-Gomez, D K; Cassidy, J; Keesman, K J; Sampaio, R; Lens, P N L

    2014-03-01

    Step changes in the organic loading rate (OLR) through variations in the influent chemical oxygen demand (CODin) concentration or in the hydraulic retention time (HRT) at constant COD/SO4(2-) ratio (0.67) were applied to create sulfide responses for the design of a sulfide control in sulfate reducing bioreactors. The sulfide was measured using a sulfide ion selective electrode (pS) and the values obtained were used to calculate proportional-integral-derivative (PID) controller parameters. The experiments were performed in an inverse fluidized bed bioreactor with automated operation using the LabVIEW software version 2009(®). A rapid response and high sulfide increment was obtained through a stepwise increase in the CODin concentration, while a stepwise decrease to the HRT exhibited a slower response with smaller sulfide increment. Irrespective of the way the OLR was decreased, the pS response showed a time-varying behavior due to sulfide accumulation (HRT change) or utilization of substrate sources that were not accounted for (CODin change). The pS electrode response, however, showed to be informative for applications in sulfate reducing bioreactors. Nevertheless, the recorded pS values need to be corrected for pH variations and high sulfide concentrations (>200 mg/L). Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. New tuning rules for PID controllers based on IMC with minimum IAE for inverse response processes

    Directory of Open Access Journals (Sweden)

    Duby Castellanos-Cárdenas

    2015-01-01

    Full Text Available In this paper new tuning rules for Proportional Integral Derivative (PID are presented, which are based on Internal Model Control (IMC. This set of equations minimizes the performance index, in this case, the Integral Absolute Error (IAE. Furthermore, a correlation is proposed in order to calculate the tuning parameter of the method, where a holding oscillation response is obtained regarding changes in the set point. This value represents a stability limit for the IMC method. The overall development is then applied to an Inverse Response System of second order and with dead time.

  1. Microchannel system for rate-controlled, sequential, and pH-responsive drug delivery.

    Science.gov (United States)

    Yang, Dasom; Lee, Jung Seung; Choi, Chang-Kuk; Lee, Hong-Pyo; Cho, Seung-Woo; Ryu, WonHyoung

    2017-12-18

    Controlled delivery of drug at a constant rate, in a sequential order, or responsive to environment conditions has been pursued for a long time to enhance the efficacy of therapeutic molecules and to minimize side effects of highly potent drugs. However, achieving such delicately-controlled delivery of a drug molecule is non-trivial and still remains a challenge. We propose the use of microchannels to control the rate, sequence, and pH-responsiveness of drug delivery for high precision and predictability. In this study, we introduce elementary drug delivery units consisting of micro-reservoirs and microchannels that have variations in their lengths, widths, numbers, and straightness. The release study demonstrates that the release rates of model drugs can be modulated by the design of microchannels. Finite element modeling of drug release predicts the performance of the drug delivery units with high accuracy. The possibility of sequential drug delivery is also demonstrated using biodegradable polymer plug in microchannels. Finally, pH-responsive delivery of drugs in microfluidic units is also discussed and demonstrated via cell viability tests. In this work, we developed microchannel-based drug delivery devices whose release rate could be accurately calculated and controlled by design of microchannel geometry. Although there have been many advances in microfabricated drug delivery systems, in particular, reservoir-based systems, no systematic investigation has been made to utilize the release channels. In our work, an equivalent electrical circuit concept was applied to the microfluidic systems for more detailed design and analysis. A microfluidic channel was regarded as an electrical resistor; their diffusion/electrical flux could be tuned with geometric factors such as length, width, a number of channel/resistor and their connections. Furthermore, from delivery rate control using channel geometry, multifunctional channel-based release systems for sequential and pH-responsive

  2. Altered core and skin temperature responses to endurance exercise in heart failure patients and healthy controls.

    Science.gov (United States)

    Benda, Nathalie M M; Eijsvogels, Thijs M H; Van Dijk, Arie P J; Bellersen, Louise; Thijssen, Dick H J; Hopman, Maria T E

    2016-01-01

    Exercise training represents a central aspect of rehabilitation of heart failure patients. Previous work on passive heating suggests impaired thermoregulatory responses in heart failure patients. However, no previous study directly examined thermoregulatory responses to an exercise bout, that is, active heating, as typically applied in rehabilitation settings in heart failure. Cross-sectional observational study to compare changes in core body temperature (Tcore) and skin temperature (Tskin) during exercise between heart failure patients and controls. Fourteen heart failure subjects (65 ± 7 years, 13:1 male:female) and 14 healthy controls (61 ± 5 years, 12:2 male:female) were included. Tcore (telemetric temperature pill) and Tskin (skin thermistors) were measured continuously during a 45-min cycle exercise at comparable relative exercise intensity. Tcore increased to a similar extent in both groups (controls 1.1 ± 0.4℃, heart failure patients 0.9 ± 0.3℃, 'time*group': p = 0.15). Tskin decreased during the initial phase of exercise in both groups, followed by an increase in Tskin in controls (1.2 ± 1.0℃), whilst Tskin remained low in HF patients (-0.3 ± 1.4℃) ('time*group': p  0.05). Heart failure patients and controls show comparable exercise-induced increase in Tcore, whilst heart failure patients demonstrate altered Tskin responses to exercise and attenuated elevation in Tskin per increase in Tcore. These impaired thermoregulatory responses to exercise are, at least partly, explained by the lower absolute workload and lower physical fitness level in heart failure patients. © The European Society of Cardiology 2015.

  3. Cortisol and subjective stress responses to acute psychosocial stress in fibromyalgia patients and control participants.

    Science.gov (United States)

    Coppens, Eline; Kempke, Stefan; Van Wambeke, Peter; Claes, Stephan; Morlion, Bart; Luyten, Patrick; Van Oudenhove, Lukas

    2017-12-11

    Hypothalamic-pituitary-adrenal (HPA) axis dysfunction may play a role in fibromyalgia (FM) pathogenesis, but remains understudied in this disorder. Furthermore, early childhood adversities (ECA) are common in FM, but whether they moderate stress reactivity is unknown. Hence, we investigated cortisol and subjective responses to acute psychosocial stress in FM and controls, while adjusting for ECA. Twenty-seven female FM patients and 24 age-matched female controls were recruited in a tertiary care center and through advertisements, respectively. The Childhood Trauma Questionnaire was used to measure ECA history. Salivary cortisol levels and subjective stress ratings were measured at multiple time points before and after the Trier Social Stress Test (TSST) was administered. Significant main effects of group [F(1,43)=7.04, p=0.011, lower in FM] and ECA [F(1,43)=5.18, p=0.028, higher in participants with ECA] were found for cortisol responses. When excluding controls with ECA (n=5), a significant group-by-time interaction was found [F(6,39)=2.60, p=0.032], driven by a blunted response to the stressor in FM compared with controls (p=0.037). For subjective stress responses, a significant main effect of group [F(1,45)=10.69, p=0.002, higher in FM] and a trend towards a group-by-time interaction effect [F(6,45)=2.05, p=0.078, higher in FM 30 minutes before and 30 and 75 minutes after the TSST, and impaired recovery (difference immediately after - 30 minutes after the TSST) in FM] were found. Blunted cortisol responsivity to the TSST was observed in FM patients compared with controls without ECA. FM patients had higher subjective stress levels compared with controls, particularly at baseline and during recovery from the TSST. In FM patients, ECA history was not associated with cortisol or subjective stress levels, or with responsivity to the TSST. Future research should investigate the mechanisms underlying HPA axis dysregulation in FM.

  4. Host control of malaria infections: constraints on immune and erythropoeitic response kinetics.

    Directory of Open Access Journals (Sweden)

    Philip G McQueen

    2008-08-01

    Full Text Available The two main agents of human malaria, Plasmodium vivax and Plasmodium falciparum, can induce severe anemia and provoke strong, complex immune reactions. Which dynamical behaviors of host immune and erythropoietic responses would foster control of infection, and which would lead to runaway parasitemia and/or severe anemia? To answer these questions, we developed differential equation models of interacting parasite and red blood cell (RBC populations modulated by host immune and erythropoietic responses. The model immune responses incorporate both a rapidly responding innate component and a slower-responding, long-term antibody component, with several parasite developmental stages considered as targets for each type of immune response. We found that simulated infections with the highest parasitemia tended to be those with ineffective innate immunity even if antibodies were present. We also compared infections with dyserythropoiesis (reduced RBC production during infection to those with compensatory erythropoiesis (boosted RBC production or a fixed basal RBC production rate. Dyserythropoiesis tended to reduce parasitemia slightly but at a cost to the host of aggravating anemia. On the other hand, compensatory erythropoiesis tended to reduce the severity of anemia but with enhanced parasitemia if the innate response was ineffective. For both parasite species, sharp transitions between the schizont and the merozoite stages of development (i.e., with standard deviation in intra-RBC development time control parasitemia. Finally, our simulations suggest that P. vivax can induce severe anemia as readily as P. falciparum for the same type of immune response, though P. vivax attacks a much smaller subset of RBCs. Since most P. vivax infections are nonlethal (if debilitating clinically, this suggests that P

  5. Analysis and control of the transient aeroelastic response of rotors during shipboard engagement and disengagement operations

    Science.gov (United States)

    Keller, Jonathan Allen

    2001-11-01

    An analysis has been developed to predict the transient aeroelastic response of a helicopter rotor system during shipboard engagement and disengagement operations. The coupled flap-lag-torsion equations of motion were developed using Hamilton's Principle and discretized spatially using the finite element method. Aerodynamics were simulated using nonlinear quasi-steady or time domain nonlinear unsteady models. The ship airwake environment was simulated with simple deterministic airwake distributions, results from experimental measurements or numerical predictions. The transient aeroelastic response of the rotor blades was then time-integrated along a specified rotor speed profile. The control of the rotor response for an analytic model of the H-46 Sea Knight rotor system was investigated with three different passive control techniques. Collective pitch scheduling was only successful in reducing the blade flapping response in a few isolated cases. In the majority of cases, the blade transient response was increased. The use of a discrete flap damper in the very low rotor speed region was also investigated. Only by raising the flap stop setting and using a flap damper four times the strength of the lag damper could the downward flap deflections be reduced. However, because the flap stop setting was raised the upward flap deflections were often increased. The use of extendable/retractable, gated leading-edge spoilers in the low rotor speed region was also investigated. Spoilers covering the outer 15% R of the rotor blade were shown to significantly reduce both the upward and downward flap response without increasing rotor torque. Previous aeroelastic analyses developed at the University of Southampton and at Penn State University were completed with flap-torsion degrees of freedom only. The addition of the lag degree of freedom was shown to significantly influence the blade response. A comparison of the two aerodynamic models showed that the nonlinear quasi

  6. Time response model of ER fluids for precision control of motors

    Energy Technology Data Exchange (ETDEWEB)

    Koyanagi, Ken' ichi [Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama (Japan)], E-mail: koyanagi@pu-toyama.ac.jp

    2009-02-01

    For improvement of control performance or new control demands of mechatronics devices using particle type ER fluids, it will be needed to further investigate a response time of the fluids. It is commonly said around 5-mili seconds, however, the formula structure of that delay has not been clear. This study aims to develop a functional damper (attenuators), that can control its viscous characteristics in real time using ER fluids as its working fluid. ER dampers are useful to accomplish high precision positioning not to prevent high speed movement of the motor. To realize the functional damper that can be manipulated according to situations or tasks, the modeling and control of ER fluids are necessary. This paper investigates time delay affects of ER fluids and makes an in-depth dynamic model of the fluid by utilizing simulation and experiment. The mathematical model has a dead-time and first ordered delays of the fluid and the high voltage amplifier for the fluid.

  7. Requirements and Challenges of Location-Based Access Control in Healthcare Emergency Response

    DEFF Research Database (Denmark)

    Vicente, Carmen Ruiz; Kirkpatrick, Michael; Ghinita, Gabriel

    2009-01-01

    ), are not sufficient to address the new challenges introduced by these location-based applications. Several recent research efforts have enhanced RBAC with spatio-temporal features. Nevertheless, the state-of-the-art does not deal with mobility of both subjects and objects and does not support the utilization......Recent advances in positioning and tracking technologies have led to the emergence of novel location-based applications that allow participants to access information relevant to their spatio-temporal context. Traditional access control models, such as role-based access control (RBAC...... emergency response scenario which highlights the novel challenges that arise when enforcing access control in an environment with moving subjects and objects. To address a realistic application scenario, we consider movement on road networks, and we identify complex access control decisions relevant...

  8. Genetic control of eosinophilia in mice: gene(s) expressed in bone marrow-derived cells control high responsiveness

    Energy Technology Data Exchange (ETDEWEB)

    Vadas, M.A.

    1982-02-01

    A heterogeneity in the capacity of strains of mice to mount eosinophilia is described. BALB/c and C3H are eosinophil high responder strains (EO-HR) and CBA and A/J are eosinophil low responder strains (EO-LR), judged by the response of blood eosinophils to Ascaris suum, and the response of blood, bone marrow, and spleen eosinophils to keyhole limpet hemocyanin given 2 days after 150 mg/kg cyclophosphamide. Some of the gene(s) for high responsiveness appear to be dominant because (EO-HR x EO-LR)F/sub 1/ mice were intermediate to high responders. This gene is expressed in bone marrow-derived cells because radiation chimeras of the type EO-HR..-->..F/sub 1/ were high responders and EO-LR..-->..F/sub 1/ were low responders. This description of a genetic control of eosinophilia in mice may be useful in understanding the role of this cell in parasite immunity and allergy.

  9. Disintegrins: integrin selective ligands which activate integrin-coupled signaling and modulate leukocyte functions

    Directory of Open Access Journals (Sweden)

    Barja-Fidalgo C.

    2005-01-01

    Full Text Available Extracellular matrix proteins and cell adhesion receptors (integrins play essential roles in the regulation of cell adhesion and migration. Interactions of integrins with the extracellular matrix proteins lead to phosphorylation of several intracellular proteins such as focal adhesion kinase, activating different signaling pathways responsible for the regulation of a variety of cell functions, including cytoskeleton mobilization. Once leukocytes are guided to sites of infection, inflammation, or antigen presentation, integrins can participate in the initiation, maintenance, or termination of the immune and inflammatory responses. The modulation of neutrophil activation through integrin-mediated pathways is important in the homeostatic control of the resolution of inflammatory states. In addition, during recirculation, T lymphocyte movement through distinct microenvironments is mediated by integrins, which are critical for cell cycle, differentiation and gene expression. Disintegrins are a family of low-molecular weight, cysteine-rich peptides first identified in snake venom, usually containing an RGD (Arg-Gly-Asp motif, which confers the ability to selectively bind to integrins, inhibiting integrin-related functions in different cell systems. In this review we show that, depending on the cell type and the microenvironment, disintegrins are able to antagonize the effects of integrins or to act agonistically by activating integrin-mediated signaling. Disintegrins have proven useful as tools to improve the understanding of the molecular events regulated by integrin signaling in leukocytes and prototypes in order to design therapies able to interfere with integrin-mediated effects.

  10. A remote controllable fiber-type near-infrared light-responsive actuator.

    Science.gov (United States)

    Shi, Qiuwei; Li, Jiahui; Hou, Chengyi; Shao, Yuanlong; Zhang, Qinghong; Li, Yaogang; Wang, Hongzhi

    2017-10-10

    A novel near-infrared (NIR) light-responsive sodium polyacrylate (PAAS)/graphene oxide (GO) fiber with a torsional pre-deformation structure is reported to realize remote control actuation. The torsional pre-deformed PAAS/GO fiber exhibited various actuation phenomena, under the control of a low powered near-infrared light (50 mW cm(-2)), such as rotating in a low-temperature range (<25 °C), rolling a distance of 10 times of its diameter within 10 s, and even driving the shape change of a fabric (the weight is as high as 20 times of the fiber itself).

  11. [Analysis of genetic control of maize response in anther culture within a diallelic set].

    Science.gov (United States)

    Satarova, T N

    2002-01-01

    The androgenic ability in anther culture in vitro was examined within a diallel set of five maize lines. The complex analysis of genetic variation components, Hayman's diagram, and genetic parameters showed that the anther response is under the control of an additive-dominant genetic system. The examined lines possessed the different correlation of dominant and recessive alleles controlling androgenesis. And 44 was the line with the biggest number of recessive genes, which determined the increase in the trait. The level of dominance varied in different loci, though in the whole the degree of dominance approached to the complete one.

  12. Physical and ecological controllers of the microbial responses to drying and rewetting in soil

    Science.gov (United States)

    Leizeaga, Ainara; Meisner, Annelein; Bååth, Erland; Rousk, Johannes

    2017-04-01

    Soil moisture is one of the most powerful factors that regulate microbial activity in soil. The variation of moisture leads to drying-rewetting (DRW) events which are known to induce enormous dynamics in soil biogeochemistry; however, the microbial underpinnings are mostly unknown. Rewetting a dry soil can result in two response patterns of bacterial growth. In the Type 1 response, bacteria start growing immediately after rewetting with rates that increase in a linear fashion to converge with those prior to the DRW within hours. This growth response coincides with respiration rates that peak immediately after rewetting to then exponentially decrease. In the Type 2 response, bacterial growth remains very low after rewetting during a lag period of up to 20 hours. Bacteria then increase their growth rates exponentially to much higher rates than those before the DRW event. This growth response coincides with respiration rates that increase to high rates immediately after rewetting that then remain elevated and sometimes even increase further in sync with the growth increase. Previous studies have shown that (i) extended drying (ii) starving before DRW and (iii) inhibitors combined with drought could change the bacterial response from Type 1 to Type 2. This suggested that the response of bacteria upon rewetting could be related to the harshness of the disturbance as experienced by the microbes. In the present study, we set out to study if reduced harshness could change a Type 2 response into a Type 1 response. We hypothesized that (1) a reduced physical harshness of drying and (2) induced tolerance to drying in microbial communities could change a Type 2 response into a Type 1 growth response upon rewetting. To address this, two experiments were performed. First, soils were partially dried to different water contents and bacterial response upon rewetting was measured. Second, soils were exposed to repeated DRW cycles (drought-tolerance. Thus, identical physical

  13. Cell microenvironment stimuli-responsive controlled-release delivery systems based on mesoporous silica nanoparticles

    Directory of Open Access Journals (Sweden)

    Chun-Ling Zhu

    2014-03-01

    Full Text Available To develop novel tumor cell microenvironment stimuli-responsive smart controlled-release delivery systems is one of the current common interests of materials science and clinical medicine. Meanwhile, mesoporous silica nanoparticles as a promising drug carrier have become the new area of interest in the field of biomedical application in recent years because of their unique characteristics and abilities to efficiently and specifically entrap cargo molecules. This review describes the more recent developments and achievements of mesoporous silica nanoparticles in drug delivery. In particular, we focus on the stimuli-responsive controlled-release systems that are able to respond to tumor cell environmental changes, such as pH, glucose, adenosine-5′-triphosphate (ATP, glutathione (GSH, and H2O2.

  14. Closed-loop response properties of a visual interneuron involved in fly optomotor control.

    Science.gov (United States)

    Ejaz, Naveed; Krapp, Holger G; Tanaka, Reiko J

    2013-01-01

    Due to methodological limitations neural function is mostly studied under open-loop conditions. Normally, however, nervous systems operate in closed-loop where sensory input is processed to generate behavioral outputs, which again change the sensory input. Here, we investigate the closed-loop responses of an identified visual interneuron, the blowfly H1-cell, that is part of a neural circuit involved in optomotor flight and gaze control. Those behaviors may be triggered by attitude changes during flight in turbulent air. The fly analyses the resulting retinal image shifts and performs compensatory body and head rotations to regain its default attitude. We developed a fly robot interface to study H1-cell responses in a 1 degree-of-freedom image stabilization task. Image shifts, induced by externally forced rotations, modulate the cell's spike rate that controls counter rotations of a mobile robot to minimize relative motion between the robot and its visual surroundings. A feedback controller closed the loop between neural activity and the rotation of the robot. Under these conditions we found the following H1-cell response properties: (i) the peak spike rate decreases when the mean image velocity is increased, (ii) the relationship between spike rate and image velocity depends on the standard deviation of the image velocities suggesting adaptive scaling of the cell's signaling range, and (iii) the cell's gain decreases linearly with increasing image accelerations. Our results reveal a remarkable qualitative similarity between the response dynamics of the H1-cell under closed-loop conditions with those obtained in previous open-loop experiments. Finally, we show that the adaptive scaling of the H1-cell's responses, while maximizing information on image velocity, decreases the cell's sensitivity to image accelerations. Understanding such trade-offs in biological vision systems may advance the design of smart vision sensors for autonomous robots.

  15. Closed-loop response properties of a visual interneuron involved in fly optomotor control

    Directory of Open Access Journals (Sweden)

    Naveed eEjaz

    2013-03-01

    Full Text Available Due to methodological limitations neural function is mostly studied under open-loop conditions. Normally, however, nervous systems operate in closed-loop where sensory input is processed to generate behavioural outputs, which again change the sensory input. Here, we investigate the closed-loop responses of an identified visual interneuron, the blowfly H1-cell, that is part of a neural circuit involved in optomotor flight and gaze control. Those behaviours may be triggered by attitude changes during flight in turbulent air. The fly analyses the resulting retinal image shifts and performs compensatory body and head rotations to regain its default attitude. We developed a fly-robot interface to study H1-cell responses in a 1 degree-of-freedom image stabilization task. Image shifts, induced by externally forced rotations, modulate the cell’s spike rate that controls counter rotations of a mobile robot to minimize relative motion between the robot and its visual surroundings. A feedback controller closed the loop between neural activity and the rotation of the robot. Under these conditions we found the following H1-cell response properties: (i the peak spike rate decreases when the mean image velocity is increased, (ii the relationship between spike rate and image velocity depends on the standard deviation of the image velocities suggesting adaptive scaling of the cell’s signalling range, and (iii the cell’s gain decreases linearly with increasing image accelerations.Our results reveal a remarkable qualitative similarity between the response dynamics of the H1-cell under closed-loop conditions with those obtained in previous open-loop experiments. Finally, we show that the adaptive scaling of the H1-cell’s responses, while maximizing information on image velocity, decreases the cell’s sensitivity to image accelerations. Understanding such trade-offs in biological vision systems may advance the design of smart vision sensors for autonomous

  16. Influence of the path establishment method on an SDN controller time response

    OpenAIRE

    Quiroz Martiña, David J.; Cervelló Pastor, Cristina

    2015-01-01

    This paper aims for the assessment of a layer 3 path establishment method, to explore the time response added to an Software Defined Networking (SDN) controller during network events and some additional operations, measured from an SDN path methodology used as a reference. The experience learned in this experimentation is presented as an alternative to monitor the processing time that new path establishment methods can bring to an SDN environment.

  17. Control of target gene specificity during metamorphosis by the steroid response gene E93

    OpenAIRE

    Mou, Xiaochun; Duncan, Dianne M.; Baehrecke, Eric H.; Duncan, Ian

    2012-01-01

    Hormonal control of sexual maturation is a common feature in animal development. A particularly dramatic example is the metamorphosis of insects, in which pulses of the steroid hormone ecdysone drive the wholesale transformation of the larva into an adult. The mechanisms responsible for this transformation are not well understood. Work in Drosophila indicates that the larval and adult forms are patterned by the same underlying sets of developmental regulators, but it is not understood how the...

  18. Control of target gene specificity during metamorphosis by the steroid response gene E93.

    Science.gov (United States)

    Mou, Xiaochun; Duncan, Dianne M; Baehrecke, Eric H; Duncan, Ian

    2012-02-21

    Hormonal control of sexual maturation is a common feature in animal development. A particularly dramatic example is the metamorphosis of insects, in which pulses of the steroid hormone ecdysone drive the wholesale transformation of the larva into an adult. The mechanisms responsible for this transformation are not well understood. Work in Drosophila indicates that the larval and adult forms are patterned by the same underlying sets of developmental regulators, but it is not understood how the same regulators pattern two distinct forms. Recent studies indicate that this ability is facilitated by a global change in the responsiveness of target genes during metamorphosis. Here we show that this shift is controlled in part by the ecdysone-induced transcription factor E93. Although long considered a dedicated regulator of larval cell death, we find that E93 is expressed widely in adult cells at the pupal stage and is required for many patterning processes at this time. To understand the role of E93 in adult patterning, we focused on a simple E93-dependent process, the induction of the Dll gene within bract cells of the pupal leg by EGF receptor signaling. In this system, we show that E93 functions to cause Dll to become responsive to EGF receptor signaling. We demonstrate that E93 is both necessary and sufficient for directing this switch. E93 likely controls the responsiveness of many other target genes because it is required broadly for patterning during metamorphosis. The wide conservation of E93 orthologs suggests that similar mechanisms control life-cycle transitions in other organisms, including vertebrates.

  19. Speed response of brushless DC motor using fuzzy PID controller under varying load condition

    Directory of Open Access Journals (Sweden)

    Akash Varshney

    2017-09-01

    Full Text Available The increasing trend towards usage of precisely controlled, high torque, efficient and low noise motors for dedicated applications has attracted the attention of researcher in Brushless DC (BLDC motors. BLDC motors can act as an acceptable alternative to the conventional motors like Induction Motors, Switched Reluctance Motors etc. This paper presents a detailed study on the performance of a BLDC motor supplying different types of loads, and at the same time, deploying different control techniques. An advance Fuzzy PID controller is compared with the commonly used PID controller. The load variations considered are of the most common types, generally encountered in practice. A comparison has been carried out in this paper by observing the dynamic speed response of motor at the time of application as well as at the time of removal of the load. The BLDC motors suffer from a major drawback of having jerky behaviour at the time of load removal. The study reveals that irrespective of the type of controller used, the gradual load variation produces better results as against sudden load variations. It is further observed that in addition to other dynamic features, the jerks produced at the time of load removal also get improved to a large extent with Fuzzy PID controller.The speed torque characteristics unraveled the fact that the jerks are minimum at the time of gradual load removal with Fuzzy PID controller in place. An attempt has been made to define these jerks by ‘Perturbation Window’.

  20. Quantitative trait loci in Anopheles gambiae controlling the encapsulation response against Plasmodium cynomolgi Ceylon

    Directory of Open Access Journals (Sweden)

    Luna Coralia

    2003-10-01

    Full Text Available Abstract Background Anopheles gambiae females are the world's most successful vectors of human malaria. However, a fraction of these mosquitoes is refractory to Plasmodium development. L3-5, a laboratory selected refractory strain, encapsulates transforming ookinetes/early oocysts of a wide variety of Plasmodium species. Previous studies on these mosquitoes showed that one major (Pen1 and two minor (Pen2, Pen3 autosomal dominant quantitative trait loci (QTLs control the melanotic encapsulation response against P. cynomolgi B, a simian malaria originating in Malaysia. Results We have investigated the response of L3-5 to infection with P. cynomolgi Ceylon, a different but related parasite species, in crosses with the susceptible strain 4Arr. Refractoriness to this parasite is incompletely recessive. Infection and genotyping of F2 intercross females at genome-spanning microsatellite loci revealed that 3 autosomal QTLs control encapsulation of this species. Two loci map to the regions containing Pen2 and Pen3. The novel QTL maps to chromosome 3R, probably to polytene division 32 or 33. Thus the relative contribution of any QTL to oocyst encapsulation varies with the species of parasite. Further, different QTLs were most readily identified in different F2 families. This, like the F1 data, suggests that L3-5 is not genetically homogeneous and that somewhat different pathways may be used to achieve an encapsulation response. Conclusion We have shown here that different QTLs are involved in responses against different Plasmodium parasites.

  1. Single-trigger dual-responsive nanoparticles for controllable and sequential prodrug activation.

    Science.gov (United States)

    Robertson, Neil M; Yang, Yang; Khan, Irfan; LaMantia, Vincent E; Royzen, Maksim; Yigit, Mehmet V

    2017-07-20

    Here we have developed a novel approach where two synergistically acting drugs were completely inactivated upon chemical immobilization on a nanoparticle template and activated in response to a chemical stimulus. The activation rate of each drug payload is controlled using a biologically inert bioorthogonal chemistry approach. By exploiting the subtle differences in the 'click-to-release' bioorthogonal reaction, we engineered a single delivery platform capable of releasing the payloads in a time-staggered manner in response to a single dose of a highly specific, yet reactive, small molecule. Incorporation of both di-axial, 'fast release', and di-equatorial, 'slow release', TCO linkers into our nanodrug assembly inhibited the activity of the drug molecules and enabled us to control the timing and activation of each payload. This single-trigger dual-responsive nanoparticle construct and its release kinetics were characterized using two molecular fluorescent probes and tested in vitro for efficient delivery of molecular payloads. In this manuscript we show that this approach was also successful in the treatment of triple negative BT-20 breast cancer cells. Our nanodrug loaded with the slow-releasing doxorubicin and fast-releasing PAC-1 prodrugs displayed a greater therapeutic response than the nanodrug which released both payloads simultaneously.

  2. Evaluation of a hospice rapid response community service: a controlled evaluation

    Directory of Open Access Journals (Sweden)

    Butler Claire

    2012-07-01

    Full Text Available Abstract Background While most people faced with a terminal illness would prefer to die at home, less than a third in England are enabled to do so with many dying in National Health Service hospitals. Patients are more likely to die at home if their carers receive professional support. Hospice rapid response teams, which provide specialist palliative care at home on a 24/7 on-call basis, are proposed as an effective way to help terminally ill patients die in their preferred place, usually at home. However, the effectiveness of rapid response teams has not been rigorously evaluated in terms of patient, carer and cost outcomes. Methods/Design The study is a pragmatic quasi-experimental controlled trial. The primary outcome for the quantitative evaluation for patients is dying in their preferred place of death. Carers’ quality of life will be evaluated using postal questionnaires sent at patient intake to the hospice service and eight months later. Carers’ perceptions of care received and the patient’s death will be assessed in one to one interviews at 6 to 8 months post bereavement. Service utilisation costs including the rapid response intervention will be compared to those of usual care. Discussion The study will contribute to the development of the evidence base on outcomes for patients and carers and costs of hospice rapid response teams operating in the community. Trial registration: Current controlled trials ISRCTN32119670.

  3. SCFKMD controls cytokinin signaling by regulating the degradation of type-B response regulators

    Science.gov (United States)

    Kim, Hyo Jung; Chiang, Yi-Hsuan; Kieber, Joseph J.; Schaller, G. Eric

    2013-01-01

    Cytokinins are plant hormones that play critical roles in growth and development. In Arabidopsis, the transcriptional response to cytokinin is regulated by action of type-B Arabidopsis response regulators (ARRs). Although central elements in the cytokinin signal transduction pathway have been identified, mechanisms controlling output remain to be elucidated. Here we demonstrate that a family of F-box proteins, called the KISS ME DEADLY (KMD) family, targets type-B ARR proteins for degradation. KMD proteins form an S-PHASE KINASE-ASSOCIATED PROTEIN1 (SKP1)/Cullin/F-box protein (SCF) E3 ubiquitin ligase complex and directly interact with type-B ARR proteins. Loss-of-function KMD mutants stabilize type-B ARRs and exhibit an enhanced cytokinin response. In contrast, plants with elevated KMD expression destabilize type-B ARR proteins leading to cytokinin insensitivity. Our results support a model in which an SCFKMD complex negatively regulates cytokinin responses by controlling levels of a key family of transcription factors. PMID:23720308

  4. Response inhibition and interference control in obsessive-compulsive spectrum disorders

    Directory of Open Access Journals (Sweden)

    Laura S van Velzen

    2014-06-01

    Full Text Available Over the past twenty years, motor response inhibition and interference control have received considerable scientific effort and attention, due to their important role in behavior and the development of neuropsychiatric disorders. Results of neuroimaging studies indicate that motor response inhibition and interference control are dependent on cortical-striatal-thalamic-cortical (CSTC circuits. Structural and functional abnormalities within the CSTC circuits have been reported for many neuropsychiatric disorders, including obsessive-compulsive disorder (OCD and related disorders, such as attention deficit hyperactivity disorder (ADHD, Tourette’s syndrome (TS and trichotillomania. These disorders also share impairments in motor response inhibition and interference control, which may underlie some of their behavioral and cognitive symptoms. Results of task-related neuroimaging studies on inhibitory functions in these disorders show that impaired task performance is related to altered recruitment of the CSTC circuits. Previous research has shown that inhibitory performance is dependent upon dopamine, noradrenaline and serotonin signaling, neurotransmitters that have been implicated in the pathophysiology of these disorders. In this review we discuss the common and disorder-specific pathophysiological mechanisms of inhibition-related dysfunction in OCD and related disorders.

  5. RNA-processing protein TDP-43 regulates FOXO-dependent protein quality control in stress response.

    Directory of Open Access Journals (Sweden)

    Tao Zhang

    2014-10-01

    Full Text Available Protein homeostasis is critical for cell survival and functions during stress and is regulated at both RNA and protein levels. However, how the cell integrates RNA-processing programs with post-translational protein quality control systems is unknown. Transactive response DNA-binding protein (TARDBP/TDP-43 is an RNA-processing protein that is involved in the pathogenesis of major neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS and frontotemporal dementia (FTD. Here, we report a conserved role for TDP-43, from C. elegans to mammals, in the regulation of protein clearance via activation of FOXO transcription factors. In response to proteotoxic insults, TDP-43 redistributes from the nucleus to the cytoplasm, promoting nuclear translocation of FOXOs and relieving an inhibition of FOXO activity in the nucleus. The interaction between TDP-43 and the FOXO pathway in mammalian cells is mediated by their competitive binding to 14-3-3 proteins. Consistent with FOXO-dependent protein quality control, TDP-43 regulates the levels of misfolded proteins. Therefore, TDP-43 mediates stress responses and couples the regulation of RNA metabolism and protein quality control in a FOXO-dependent manner. The results suggest that compromising the function of TDP-43 in regulating protein homeostasis may contribute to the pathogenesis of related neurodegenerative diseases.

  6. The Response Clamp: Functional characterization of neural systems using closed-loop control

    Directory of Open Access Journals (Sweden)

    Avner eWallach

    2013-01-01

    Full Text Available The voltage clamp method, pioneered by Hodgkin, Huxley and Katz, laid the foundations to neurophysiological research. Its core rationale is the use of closed-loop control as a tool for system characterization. A recently introduced method, the response clamp, extends the voltage clamp rationale to the functional, phenomenological level. The method consists of on-line estimation of a response variable of interest (e.g. the probability of response or its latency and a simple feedback control mechanism designed to tightly converge this variable towards a desired trajectory. In the present contribution I offer a perspective on this novel method and its applications in the broader context of system identification and characterization. First, I demonstrate how internal state variables are exposed using the method, and how the use of several controllers may allow for a detailed, multi-variable characterization of the system. Second, I discuss three different categories of applications of the method: (i exploration of intrinsically generated dynamics, (ii exploration of extrinsically generated dynamics and (iii generation of input-output trajectories. The relation of these categories to similar uses in the voltage clamp and other techniques is also discussed. Finally, I discuss the method’s limitations, as well as its possible synthesis with existing complementary approaches.

  7. Pruritic and vascular responses induced by serotonin in patients with atopic dermatitis and in healthy controls.

    Science.gov (United States)

    Rausl, Aram; Nordlind, Klas; Wahlgren, Carl-Fredrik

    2013-05-01

    Atopic dermatitis (AD) is a chronic inflammatory skin disease with often severe itch. The aim of this study was to determine the pruritogenic and vascular effect of serotonin (5-hydroxytryptamine; 5-HT) in patients with AD and in healthy controls. A 50 µg dose of 5-HT was injected intradermally into non-lesional skin of 25 patients with AD and 25 healthy control individuals, and the effect compared with 0.2 µg histamine as a positive control, and buffer as a negative control. Pruritus was recorded by the subjects, using a computerized visual analogue scale, while flare and wheal were recorded by the investigator. There was no qualitative or quantitative difference in 5-HT-induced itch between patients and control subjects, or between males and females. However, reduced flare and wheal were found in the patient group for 5-HT. There were no correlations between clinical findings (i.e. eczema severity, clinical pruritus) and recorded experimental itch, or flare or wheal responses for 5-HT, in the patients with AD. In both groups a shorter itch latency was found for 5-HT compared with histamine. Through the use of intradermal injections, making it possible to calculate the dose of substance delivered, a lower vascular response to 5-HT was shown in patients with AD compared with healthy controls. In addition to confirming a pruritogenic role of 5-HT in both patients with AD and healthy controls, we found a shorter itch latency for 5-HT compared with histamine in both groups. The short itch latency time may indicate a direct effect of 5-HT on itch receptors.

  8. Ecophysiological responses of a young blue gum (Eucalyptus globulus) plantation to weed control.

    Science.gov (United States)

    Eyles, Alieta; Worledge, Dale; Sands, Peter; Ottenschlaeger, Maria L; Paterson, Steve C; Mendham, Daniel; O'Grady, Anthony P

    2012-08-01

    Early weed control may improve the growth of forest plantations by influencing soil water and nutrient availability. To understand eucalypt growth responses to weed control, we examined the temporal responses of leaf gas-exchange, leaf nitrogen concentration (N) and water status of 7-month-old Eucalyptus globulus L. trees in a paired-plot field trial. In addition, we monitored the growth, leaf N and water status of the competing vegetation in the weed treatment. By the end of the 11-month experiment, complete weed control (WF treatment) of largely woody competitors increased the basal diameter of E. globulus by 14%. As indicated by pre-dawn water potentials of > - 0.05 MPa, interspecies competition for water resources was minimal at this site. In contrast, competition for N appeared to be the major factor limiting growth. Estimations of total plot leaf N (g m(-2) ground) showed that competing vegetation accounted for up to 70% of the total leaf N at the start of the trial. This value fell to 15% by the end of the trial. Despite increased leaf N(area) in WF trees 5 months after imposition of weed control, the photosynthetic capacity (A(1500)) of E. globulus was unaffected by treatment suggesting that the growth gains from weed control were largely unrelated to changes in leaf-level photosynthesis. Increased nutrient availability brought about by weed control enabled trees to increase investment into leaf-area production. Estimates of whole-tree carbon budget based on direct measurements of dark respiration and A(1500) allowed us to clearly demonstrate the importance of leaf area driving greater productivity following early weed control in a nutrient-limited site.

  9. Vibration reduction in helicopters using active control of structural response (ACSR) with improved aerodynamic modeling

    Science.gov (United States)

    Cribbs, Richard Clay

    This dissertation describes the development of a coupled rotor/flexible fuselage aeroelastic response model including rotor/fuselage aerodynamic interactions. This model is used to investigate fuselage vibrations and their suppression using active control of structural response (ACSR). The fuselage, modeled by a three dimensional structural dynamic finite element model, is combined with a flexible, four-bladed, hingeless rotor. Each rotor blade is structurally modeled as an isotropic Euler-Bernoulli beam with coupled flap-lag-torsional dynamics assuming moderate deflections. A free wake model is incorporated into the aeroelastic response model and is validated against previous studies. Two and three dimensional sources model the fuselage aerodynamics. Direct aerodynamic influences of the rotor and wake on the fuselage are calculated by integrating pressures over the surface of the fuselage. The fuselage distorts the wake and influences the air velocities at the rotor which alters the aerodynamic loading. This produces fully coupled rotor/fuselage aerodynamic interactions. The influence of the aerodynamic refinements on vibrations is studied in detail. Results indicate that a free wake model and the inclusion of fuselage aerodynamic effects on the rotor and wake are necessary for vibration prediction at all forward speeds. The direct influence of rotor and wake aerodynamics on the fuselage plays a minor role in vibrations. Accelerations with the improved aerodynamic model are significantly greater than uniform inflow results. The influence of vertical separation between the rotor and fuselage on vibrations is also studied. An ACSR control algorithm is developed that preferentially reduces accelerations at selected airframe locations of importance. Vibration reduction studies are carried out using this improved control algorithm and a basic algorithm studied previously at UCLA. Both ACSR methods markedly reduce acceleration amplitudes with no impact on the rotor

  10. Lottery incentives did not improve response rate to a mailed survey: a randomized controlled trial.

    Science.gov (United States)

    Harris, Ian A; Khoo, Oliver K; Young, Jane M; Solomon, Michael J; Rae, Hamish

    2008-06-01

    Our study aimed to examine the effect of an instant lottery ticket incentive on the response rate to a mailed questionnaire in a population of trauma patients. A randomized controlled trial at a major trauma center with 728 patients randomized into 2 groups prior to mailing of a questionnaire. One group of patients (Group A) had a sentence inserted into the cover letter stating that they would receive a $4 instant lottery ticket upon receipt of a completed questionnaire; Group B did not have an incentive. The response rate for both groups was measured after the initial mailing and at the end of the study. The results were analyzed using the X2 test to compare 2 proportions and a P value of .05 was considered significant. The early response rate in Group A was lower than in Group B, and the response rates for both groups were similar at final follow-up. The differences at both time periods were not statistically significant. The use of an instant lottery ticket incentive did not improve the response rate to a mailed questionnaire.

  11. Active control of environmental noise, VIII: increasing the response to primary source changes including unpredictable noise

    Science.gov (United States)

    Wright, S. E.; Atmoko, H.; Vuksanovic, B.

    2004-07-01

    Conventional adaptive cancellation systems using traditional transverse finite impulse response (FIR) filters, together with least mean square (LMS) adaptive algorithms, well known in active noise control, are slow to adapt to primary source changes. This makes them inappropriate for cancelling rapidly changing noise, including unpredictable noise such as speech and music. Secondly, the cancelling structures require considerable computational processing effort to adapt to primary source and plant changes, particularly for multi-channel systems. This paper describes methods to increase the adaptive speed to primary source changes in large enclosed spaces and outdoor environments. A method is described that increases the response to time varying periodic noise using traditional transverse FIR filters. Here a multi-passband filter, with individual variable adaptive step sizes for each passband is automatically adjusted according to the signal level in each band. This creates a similar adaptive response for all frequencies within the total pass-band, irrespective of amplitude, minimizing the signal distortion and increasing the combined adaptive speed. Unfortunately, there is a limit to the adaptive speed using the above method as classical transverse FIR filters have a finite adaptive speed given by the stability band zero bandwidth. For rapidly changing periodic noise and unpredictable non-stationary noise, a rapid to instantaneous response is required. In this case the on-line adaptive FIR filters are dispensed with and replaced by a time domain solution that gives virtually instantaneous cancellation response (infinite adaptive speed) to primary source changes, and is computationally efficient.

  12. The rate of immune escape vanishes when multiple immune responses control an HIV infection.

    Science.gov (United States)

    van Deutekom, Hanneke W M; Wijnker, Gilles; de Boer, Rob J

    2013-09-15

    During the first months of HIV infection, the virus typically evolves several immune escape mutations. These mutations are found in epitopes in viral proteins and reduce the impact of the CD8⁺ T cells specific for these epitopes. Recent data show that only a subset of the epitopes escapes, that most of these escapes evolve early, and that the rate of immune escape slows down considerably. To investigate why the evolution of immune escape slows down over the time of infection, we have extended a consensus mathematical model to allow several immune responses to control the virus together. In the extended model, most escapes also occur early, and the immune escape rate becomes small later, and typically only a minority of the epitopes escape. We show that escaping one of the many immune responses provides little advantage after viral setpoint has been approached because the total killing rate hardly depends on the breadth of the immune response. If the breadth of the immune response slowly wanes during disease progression, the model predicts an increase in the rate of immune escape at late stages of infection. Overall, the most striking prediction of the model is that HIV evolves a small number of immune escapes, in both relative and absolute terms, when the CTL immune response is broad.

  13. Effects of Aversive Classical Conditioning on Sexual Response in Women With Dyspareunia and Sexually Functional Controls.

    Science.gov (United States)

    Both, Stephanie; Brauer, Marieke; Weijenborg, Philomeen; Laan, Ellen

    2017-05-01

    In dyspareunia-a somatically unexplained vulvovaginal pain associated with sexual intercourse-learned pain-related fear and inhibited sexual arousal are supposed to play a pivotal role. Based on research findings indicating that enhanced pain conditioning is involved in the etiology and maintenance of chronic pain, in the present study it was hypothesized that enhanced pain conditioning also might be involved in dyspareunia. To test whether learned associations between pain and sex negatively affect sexual response; whether women with dyspareunia show stronger aversive learning; and whether psychological distress, pain-related anxiety, vigilance, catastrophizing, and sexual excitation and inhibition were associated with conditioning effects. Women with dyspareunia (n = 36) and healthy controls (n = 35) completed a differential conditioning experiment, with one erotic picture (the CS + ) paired with a painful unconditional stimulus and one erotic picture never paired with pain (the CS - ). Genital sexual response was measured by vaginal photoplethysmography, and ratings of affective value and sexual arousal in response to the CS + and CS - were obtained. Psychological distress, pain cognitions, and sexual excitation and inhibition were assessed by validated questionnaires. The two groups showed stronger negative affect and weaker subjective sexual arousal to the CS + during the extinction phase, but, contrary to expectations, women with dyspareunia showed weaker differential responding. Controls showed more prominent lower genital response to the CS + during acquisition than women with dyspareunia. In addition, women with dyspareunia showed stronger expectancy for the unconditional stimulus in response to the safe CS - . Higher levels of pain-related fear, pain catastrophizing, and sexual inhibition were associated with weaker differential conditioning effects. Pairing of sex with pain negatively affects sexual response. The results indicate that a learned

  14. The effects of response-cost punishment on instructional control during a choice task.

    Science.gov (United States)

    Fox, Adam E; Pietras, Cynthia J

    2013-05-01

    The present study investigated the effects of punishing responses inconsistent with rules on instructional control during a choice task. In a procedure modeled after Hackenberg and Joker (1994), 7 adults were presented with repeated choices between progressive- and fixed-time schedules of reinforcement and were given instructions (rules) for how to respond to maximize earnings. Across sessions, the progressive-time schedule step size was manipulated so that the instructions became increasingly inaccurate, and deviating from the instructions produced greater earnings. The experiment consisted of two phases, Penalty and No Penalty. During the Penalty phase, deviating from the instructions produced a money-loss penalty (response-cost punishment). Two participants showed persistent instructional control and therefore completed only one phase (Penalty or No Penalty), and 1 participant showed little instructional control during the Penalty phase until the punishment magnitude was increased. In all 4 participants who experienced both Penalty and No Penalty phases, punishment increased the consistency of choices with the instructions, and in 2 of these participants punishment increased the progressive-schedule step size at which choices began to systematically deviate from the instructions. These results show that monetary penalties for breaking with rules may enhance instructional control, but that deviations from rules still occur under punishment when such deviations produce greater reinforcement than rule following. © Society for the Experimental Analysis of Behavior.

  15. Frequency Response Analysis of Current Controllers for Selective Harmonic Compensation in Active Power Filters

    DEFF Research Database (Denmark)

    Lascu, C.; Asiminoaei, L.; Boldea, I.

    2009-01-01

    different. It emerges that the fourth one has superior behavior and robustness and can stably work at higher frequencies than the others. Theoretical findings and analysis are supported by comparative experimental results on a 7-kVA laboratory setup. The highest harmonic frequency that can be stably...... to achieve zero phase shift and unity gain in the closed-loop transfer function for selected harmonics. The complete current controller is the superposition of all individual harmonic controllers and may be implemented in various reference frames. The analysis is focused on the comparison of harmonic...... and total closed-loop transfer functions for each controller. Analytical similarities and differences between schemes in terms of frequency response characteristics are emphasized. It is concluded that three of them have identical harmonic behavior despite the fact that their implementation is significantly...

  16. Post-error action control is neurobehaviorally modulated under conditions of constant speeded response

    Directory of Open Access Journals (Sweden)

    Takahiro eSoshi

    2015-01-01

    Full Text Available Post-error slowing is an error recovery strategy that contributes to action control, and occurs after errors in order to prevent future behavioral flaws. Error recovery often malfunctions in clinical populations, but the relationship between behavioral traits and recovery from error is unclear in healthy populations. The present study investigated the relationship between impulsivity and error recovery by simulating a speeded response situation using a Go/No-go paradigm that forced the participants to constantly make accelerated responses prior to stimuli disappearance (stimulus duration: 250 ms. Neural correlates of post-error processing were examined using event-related potentials (ERPs. Impulsivity traits were measured with self-report questionnaires (BIS-11, BIS/BAS. Behavioral results demonstrated that the commission error for No-go trials was 15%, but post-error slowing did not take place immediately. Delayed post-error slowing was negatively correlated with error rates and impulsivity traits, showing that response slowing was associated with reduced error rates and changed with impulsivity. Response-locked error ERPs were clearly observed for the error trials. Contrary to previous studies, error ERPs were not significantly related to post-error slowing. Stimulus-locked N2 was negatively correlated with post-error slowing and positively correlated with impulsivity traits at the second post-error Go trial: larger N2 activity was associated with greater post-error slowing and less impulsivity. In summary, under constant speeded conditions, error monitoring was dissociated from post-error action control, and post-error slowing did not occur quickly. Furthermore, post-error slowing and its neural correlate (N2 were modulated by impulsivity traits. These findings suggest that there may be clinical and practical efficacy of maintaining cognitive control of actions during error recovery under common daily environments that frequently evoke

  17. Two Persons with Multiple Disabilities Use Camera-Based Microswitch Technology to Control Stimulation with Small Mouth and Eyelid Responses

    Science.gov (United States)

    Lancioni, Giulio E.; Bellini, Domenico; Oliva, Doretta; Singh, Nirbhay N.; O'Reilly, Mark F.; Sigafoos, Jeff; Lang, Russell

    2012-01-01

    Background: A camera-based microswitch technology was recently developed to monitor small facial responses of persons with multiple disabilities and allow those responses to control environmental stimulation. This study assessed such a technology with 2 new participants using slight variations of previous responses. Method: The technology involved…

  18. Effects of Granular Control on Customers’ Perspective and Behavior with Automated Demand Response Systems

    Energy Technology Data Exchange (ETDEWEB)

    Schetrit, Oren; Kim, Joyce; Yin, Rongxin; Kiliccote, Sila

    2014-08-01

    Automated demand response (Auto-DR) is expected to close the loop between buildings and the grid by providing machine-to-machine communications to curtail loads without the need for human intervention. Hence, it can offer more reliable and repeatable demand response results to the grid than the manual approach and make demand response participation a hassle-free experience for customers. However, many building operators misunderstand Auto-DR and are afraid of losing control over their building operation. To ease the transition from manual to Auto-DR, we designed and implemented granular control of Auto-DR systems so that building operators could modify or opt out of individual load-shed strategies whenever they wanted. This paper reports the research findings from this effort demonstrated through a field study in large commercial buildings located in New York City. We focused on (1) understanding how providing granular control affects building operators’ perspective on Auto-DR, and (2) evaluating the usefulness of granular control by examining their interaction with the Auto-DR user interface during test events. Through trend log analysis, interviews, and surveys, we found that: (1) the opt-out capability during Auto-DR events can remove the feeling of being forced into load curtailments and increase their willingness to adopt Auto-DR; (2) being able to modify individual load-shed strategies allows flexible Auto-DR participation that meets the building’s changing operational requirements; (3) a clear display of automation strategies helps building operators easily identify how Auto-DR is functioning and can build trust in Auto-DR systems.

  19. Optimizing Industrial Consumer Demand Response Through Disaggregation, Hour-Ahead Pricing, and Momentary Autonomous Control

    Science.gov (United States)

    Abdulaal, Ahmed

    The work in this study addresses the current limitations of the price-driven demand response (DR) approach. Mainly, the dependability on consumers to respond in an energy aware conduct, the response timeliness, the difficulty of applying DR in a busy industrial environment, and the problem of load synchronization are of utmost concern. In order to conduct a simulation study, realistic price simulation model and consumers' building load models are created using real data. DR action is optimized using an autonomous control method, which eliminates the dependency on frequent consumer engagement. Since load scheduling and long-term planning approaches are infeasible in the industrial environment, the proposed method utilizes instantaneous DR in response to hour-ahead price signals (RTP-HA). Preliminary simulation results concluded savings at the consumer-side at the cost of increased supplier-side burden due to the aggregate effect of the universal DR policies. Therefore, a consumer disaggregation strategy is briefly discussed. Finally, a refined discrete-continuous control system is presented, which utilizes multi-objective Pareto optimization, evolutionary programming, utility functions, and bidirectional loads. Demonstrated through a virtual testbed fit with real data, the new system achieves momentary optimized DR in real-time while maximizing the consumer's wellbeing.

  20. Association between physical fitness, parasympathetic control, and proinflammatory responses to mental stress.

    Science.gov (United States)

    Hamer, Mark; Steptoe, Andrew

    2007-01-01

    To examine the association between physical fitness, cardiac parasympathetic control, and inflammatory cytokine responses to mental stress. Exercise and physical fitness may act as a buffer to the detrimental effects of psychosocial stress exposure. Participants were 207 men and women (52 +/- 3 years) drawn from the Whitehall II epidemiological cohort. Participants completed two mental stressors consisting of a 5-minute Stroop task and a 5-minute mirror tracing task. Blood samples were obtained during baseline and 45 minutes post stress. Heart rate variability (HRV) was measured during baseline, stress, and recovery. Physical fitness was assessed from a submaximal exercise test. Interleukin (IL)-6 and IL-1 receptor antagonist were increased significantly at 45 minutes post stress. Multiple linear regression analysis, adjusted for age, body mass index, gender, smoking, alcohol, grade of employment, and basal levels of inflammatory markers demonstrated that exercise heart rate (a fitness indicator) was related to IL-6 (beta = 0.24; p = .005) and tumor necrosis factor (TNF)-alpha responses to stress (beta = 0.27; p = .002). Exercise heart rate was also related to the HRV response to stress (beta = -0.23; p = .02). A higher systolic blood pressure response to exercise was a predictor of TNF-alpha responses to stress (beta = 0.18; p = .03). Physical fitness (as indexed by lower exercise heart rate) is associated with smaller inflammatory cytokine responses to acute mental stress, an effect that may be partly mediated through parasympathetic pathways. This may be one of the mechanisms by which physical fitness confers protection against cardiovascular risk.

  1. Innovative Seismic Response-Controlled System with Shear Wall and Concentrated Dampers in Lower Stories

    Directory of Open Access Journals (Sweden)

    Tsubasa Tani

    2017-10-01

    Full Text Available A new structural control system using damper-installed shear walls in lower stories with reduced stiffness is proposed for vibration control of high-rise RC buildings. That system has some design variables, i.e., height of shear wall, degree of stiffness reduction at lower stories, and quantity of dampers. In this paper, some parametric studies on the shear-beam model with a stiff beam against two kinds of ground motion, a pulse-type sinusoidal wave and a resonant sinusoidal wave, are conducted to clarify the vibration characteristics of the proposed structural control system. It is shown that the optimal combination of design parameters depends on the input ground motion. It is also shown that it is possible to prevent from increasing the response under the one-cycle sinusoidal input resonant to the lowest mode and reduce the steady-state response under the harmonic input with the resonant fundamental period by reducing the stiffness in the lower structure and increasing the damper deformation.

  2. Microfluidic synthesis of microfibers for magnetic-responsive controlled drug release and cell culture.

    Directory of Open Access Journals (Sweden)

    Yung-Sheng Lin

    Full Text Available This study demonstrated the fabrication of alginate microfibers using a modular microfluidic system for magnetic-responsive controlled drug release and cell culture. A novel two-dimensional fluid-focusing technique with multi-inlets and junctions was used to spatiotemporally control the continuous laminar flow of alginate solutions. The diameter of the manufactured microfibers, which ranged from 211 µm to 364 µm, could be well controlled by changing the flow rate of the continuous phase. While the model drug, diclofenac, was encapsulated into microfibers, the drug release profile exhibited the characteristic of a proper and steady release. Furthermore, the diclofenac release kinetics from the magnetic iron oxide-loaded microfibers could be controlled externally, allowing for a rapid drug release by applying a magnetic force. In addition, the successful culture of glioblastoma multiforme cells in the microfibers demonstrated a good structural integrity and environment to grow cells that could be applied in drug screening for targeting cancer cells. The proposed microfluidic system has the advantages of ease of fabrication, simplicity, and a fast and low-cost process that is capable of generating functional microfibers with the potential for biomedical applications, such as drug controlled release and cell culture.

  3. Microfluidic synthesis of microfibers for magnetic-responsive controlled drug release and cell culture.

    Science.gov (United States)

    Lin, Yung-Sheng; Huang, Keng-Shiang; Yang, Chih-Hui; Wang, Chih-Yu; Yang, Yuh-Shyong; Hsu, Hsiang-Chen; Liao, Yu-Ju; Tsai, Chia-Wen

    2012-01-01

    This study demonstrated the fabrication of alginate microfibers using a modular microfluidic system for magnetic-responsive controlled drug release and cell culture. A novel two-dimensional fluid-focusing technique with multi-inlets and junctions was used to spatiotemporally control the continuous laminar flow of alginate solutions. The diameter of the manufactured microfibers, which ranged from 211 µm to 364 µm, could be well controlled by changing the flow rate of the continuous phase. While the model drug, diclofenac, was encapsulated into microfibers, the drug release profile exhibited the characteristic of a proper and steady release. Furthermore, the diclofenac release kinetics from the magnetic iron oxide-loaded microfibers could be controlled externally, allowing for a rapid drug release by applying a magnetic force. In addition, the successful culture of glioblastoma multiforme cells in the microfibers demonstrated a good structural integrity and environment to grow cells that could be applied in drug screening for targeting cancer cells. The proposed microfluidic system has the advantages of ease of fabrication, simplicity, and a fast and low-cost process that is capable of generating functional microfibers with the potential for biomedical applications, such as drug controlled release and cell culture.

  4. Optimal control of wind-farm boundary layers: effect of turbine response time

    Science.gov (United States)

    Munters, Wim; Meyers, Johan

    2016-11-01

    Complex turbine wake interactions play an important role in overall energy extraction in large wind farms. Current control strategies optimize individual turbine power, and lead to significant energy losses in wind farms compared to lone-standing turbines. In recent work, an optimal control framework for dynamic induction control of wind farms and their interaction with the atmospheric boundary layer (ABL) was introduced, with the aim of mitigating such losses. The framework applies a receding horizon methodology, in which the ABL state is modeled through large-eddy simulations. Previously, the framework was applied to both fully-developed and spatially developing wind farms, for which respective energy gains of 16% and 7% were obtained, albeit at the cost of additional turbine loading variability. Here, we quantify the trade-off between increased power extraction and smoothed turbine dynamics by varying the turbine response time in the control framework. We consider simulation cases restricted to underinduction compared to Betz-optimal induction, as well as cases that also allow overinduction. In addition, efforts on replicating optimized power gains with practical controllers are presented. The authors are supported by the ERC (ActiveWindFarms, Grant No.: 306471).

  5. Genetic response in masseter muscle after orthognathic surgery in comparison with healthy controls - A Microarray study.

    Science.gov (United States)

    Marewski, Maya; Petto, Carola; Schneider, Matthias; Harzer, Winfried

    2017-04-01

    One third of adult patients with orthognathic surgery of a prognathic or retrognathic mandible show relapse. The sagittal split osteotomy of the mandible leads to a displacement of both parts up to 10 mm without any changes of muscle attachment. Changed mandible length needs adaptation of muscle capacity because of changed force to moment ratio. The aim of this Microarray study was to analyze the general genetic response of masseter muscle in patients with retrognathism or prognathism of the mandible six months after surgery in comparison with healthy untreated controls. We found in tissue samples from masseter muscle a reduction of different entities between patients and controls but less in retrognathic than in prognathic patients (274/429). The different entities to controls in prognathia were reduced from 1862 to 1749 but increased in retrognathia from 1070 to 1563. We have to consider that the total amount of different entities to the controls is higher in patients with prognathic mandible (7364) because of their strong genetic controlled development compared with that in patients with retrognathic mandible (4126), which is more environmentally influenced. It can be concluded that function follows form after surgical change with high inheritance. In retrognathic patients the adaptation could be delayed or the capacity of regeneration potential is not sufficient. Copyright © 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  6. Disparity vergence responses before versus after repetitive vergence therapy in binocularly normal controls.

    Science.gov (United States)

    Talasan, Henry; Scheiman, Mitchell; Li, Xiaobo; Alvarez, Tara L

    2016-01-01

    This study sought to determine whether significant changes would be observed between vergence eye movements before and after 12 hr of repetitive vergence therapy (1 hr per day on different days) in subjects with normal binocular vision compared to controls. Disparity vergence responses from 23 subjects were studied. An assessment protocol that minimized the influence of the near dissociated phoria on the disparity vergence system was designed. The following parameters were quantified for the responses: latency, time to peak velocity, settling time, peak velocity, and accuracy (difference between the response and stimulus amplitudes). The following outcomes were observed when comparing the results after vergence therapy to the baseline measurements: (a) near point of convergence and near dissociated phoria did not significantly change (p > 0.15); (b) latency, time to peak velocity, and settling time significantly decreased (p ≤ 0.01); and (c) accuracy significantly improved (p vergence peak velocity is dependent on the subject's near dissociated phoria. The accuracy and temporal properties of vergence eye movement responses from subjects with normal binocular vision can be improved after vergence therapy. These methods can be utilized within future studies to quantitatively assess vergence therapy techniques for patients with binocular dysfunction.

  7. Specific executive control impairments in Tourette syndrome: The role of response inhibition.

    Science.gov (United States)

    Yaniv, Asaf; Benaroya-Milshtein, Noa; Steinberg, Tamar; Ruhrrman, Dafna; Apter, Alan; Lavidor, Michal

    2017-02-01

    Tourette syndrome (TS) is a childhood-onset disorder characterized by motor and vocal tics. While cognitive features of common comorbid conditions such as attention deficit hyperactive disorder and obsessive compulsive disorder have been widely investigated, the cognitive profile of TS patients remains to be precisely defined. In this regard, the executive functions system (EF) is of especial interest. The aim of the study was to delineate the various components of executive processes in adult TS patients. A sample of 19 adults diagnosed with TS and 19 age-matched control subjects underwent computerized battery of executive tasks, as well as block design and memory tests. All patients received a thorough clinical assessment with an emphasis on illness severity. There was a marked impairment in response inhibition ability regardless of comorbid conditions, In addition, there was decreased accuracy in set shifting, but not in response time. These results imply that impaired response inhibition in the EF system is the primary cognitive impairment in TS and that many of the previously reported impaired executive functions in TS are secondary to this impairment. This finding of impaired response inhibition in TS may imply that rehabilitation of this inhibition component could prove to be an important therapeutic strategy in adults with TS. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. ABA control of plant macroelement membrane transport systems in response to water deficit and high salinity.

    Science.gov (United States)

    Osakabe, Yuriko; Yamaguchi-Shinozaki, Kazuko; Shinozaki, Kazuo; Tran, Lam-Son Phan

    2014-04-01

    Plant growth and productivity are adversely affected by various abiotic stressors and plants develop a wide range of adaptive mechanisms to cope with these adverse conditions, including adjustment of growth and development brought about by changes in stomatal activity. Membrane ion transport systems are involved in the maintenance of cellular homeostasis during exposure to stress and ion transport activity is regulated by phosphorylation/dephosphorylation networks that respond to stress conditions. The phytohormone abscisic acid (ABA), which is produced rapidly in response to drought and salinity stress, plays a critical role in the regulation of stress responses and induces a series of signaling cascades. ABA signaling involves an ABA receptor complex, consisting of an ABA receptor family, phosphatases and kinases: these proteins play a central role in regulating a variety of diverse responses to drought stress, including the activities of membrane-localized factors, such as ion transporters. In this review, recent research on signal transduction networks that regulate the function ofmembrane transport systems in response to stress, especially water deficit and high salinity, is summarized and discussed. The signal transduction networks covered in this review have central roles in mitigating the effect of stress by maintaining plant homeostasis through the control of membrane transport systems. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

  9. Ghrelin potentiates cardiac reactivity to stress by modulating sympathetic control and beta-adrenergic response.

    Science.gov (United States)

    Camargo-Silva, Gabriel; Turones, Larissa Córdova; da Cruz, Kellen Rosa; Gomes, Karina Pereira; Mendonça, Michelle Mendanha; Nunes, Allancer; de Jesus, Itamar Guedes; Colugnati, Diego Basile; Pansani, Aline Priscila; Pobbe, Roger Luis Henschel; Santos, Robson; Fontes, Marco Antônio Peliky; Guatimosim, Silvia; de Castro, Carlos Henrique; Ianzer, Danielle; Ferreira, Reginaldo Nassar; Xavier, Carlos Henrique

    2018-03-01

    Prior evidence indicates that ghrelin is involved in the integration of cardiovascular functions and behavioral responses. Ghrelin actions are mediated by the growth hormone secretagogue receptor subtype 1a (GHS-R1a), which is expressed in peripheral tissues and central areas involved in the control of cardiovascular responses to stress. In the present study, we assessed the role of ghrelin - GHS-R1a axis in the cardiovascular reactivity to acute emotional stress in rats. Ghrelin potentiated the tachycardia evoked by restraint and air jet stresses, which was reverted by GHS-R1a blockade. Evaluation of the autonomic balance revealed that the sympathetic branch modulates the ghrelin-evoked positive chronotropy. In isolated hearts, the perfusion with ghrelin potentiated the contractile responses caused by stimulation of the beta-adrenergic receptor, without altering the amplitude of the responses evoked by acetylcholine. Experiments in isolated cardiomyocytes revealed that ghrelin amplified the increases in calcium transient changes evoked by isoproterenol. Taken together, our results indicate that the Ghrelin-GHS-R1a axis potentiates the magnitude of stress-evoked tachycardia by modulating the autonomic nervous system and peripheral mechanisms, strongly relying on the activation of cardiac calcium transient and beta-adrenergic receptors. Copyright © 2018 Elsevier Inc. All rights reserved.

  10. Osmotic stress responses and plant growth controlled by potassium transporters in Arabidopsis.

    Science.gov (United States)

    Osakabe, Yuriko; Arinaga, Naoko; Umezawa, Taishi; Katsura, Shogo; Nagamachi, Keita; Tanaka, Hidenori; Ohiraki, Haruka; Yamada, Kohji; Seo, So-Uk; Abo, Mitsuru; Yoshimura, Etsuro; Shinozaki, Kazuo; Yamaguchi-Shinozaki, Kazuko

    2013-02-01

    Osmotic adjustment plays a fundamental role in water stress responses and growth in plants; however, the molecular mechanisms governing this process are not fully understood. Here, we demonstrated that the KUP potassium transporter family plays important roles in this process, under the control of abscisic acid (ABA) and auxin. We generated Arabidopsis thaliana multiple mutants for K(+) uptake transporter 6 (KUP6), KUP8, KUP2/SHORT HYPOCOTYL3, and an ABA-responsive potassium efflux channel, guard cell outward rectifying K(+) channel (GORK). The triple mutants, kup268 and kup68 gork, exhibited enhanced cell expansion, suggesting that these KUPs negatively regulate turgor-dependent growth. Potassium uptake experiments using (86)radioactive rubidium ion ((86)Rb(+)) in the mutants indicated that these KUPs might be involved in potassium efflux in Arabidopsis roots. The mutants showed increased auxin responses and decreased sensitivity to an auxin inhibitor (1-N-naphthylphthalamic acid) and ABA in lateral root growth. During water deficit stress, kup68 gork impaired ABA-mediated stomatal closing, and kup268 and kup68 gork decreased survival of drought stress. The protein kinase SNF1-related protein kinases 2E (SRK2E), a key component of ABA signaling, interacted with and phosphorylated KUP6, suggesting that KUP functions are regulated directly via an ABA signaling complex. We propose that the KUP6 subfamily transporters act as key factors in osmotic adjustment by balancing potassium homeostasis in cell growth and drought stress responses.

  11. Precision metabolic engineering: The design of responsive, selective, and controllable metabolic systems.

    Science.gov (United States)

    McNerney, Monica P; Watstein, Daniel M; Styczynski, Mark P

    2015-09-01

    Metabolic engineering is generally focused on static optimization of cells to maximize production of a desired product, though recently dynamic metabolic engineering has explored how metabolic programs can be varied over time to improve titer. However, these are not the only types of applications where metabolic engineering could make a significant impact. Here, we discuss a new conceptual framework, termed "precision metabolic engineering," involving the design and engineering of systems that make different products in response to different signals. Rather than focusing on maximizing titer, these types of applications typically have three hallmarks: sensing signals that determine the desired metabolic target, completely directing metabolic flux in response to those signals, and producing sharp responses at specific signal thresholds. In this review, we will first discuss and provide examples of precision metabolic engineering. We will then discuss each of these hallmarks and identify which existing metabolic engineering methods can be applied to accomplish those tasks, as well as some of their shortcomings. Ultimately, precise control of metabolic systems has the potential to enable a host of new metabolic engineering and synthetic biology applications for any problem where flexibility of response to an external signal could be useful. Copyright © 2015 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  12. Influence of a Suggestive Placebo Intervention on Psychobiological Responses to Social Stress: A Randomized Controlled Trial.

    Science.gov (United States)

    Zimmermann-Viehoff, Frank; Steckhan, Nico; Meissner, Karin; Deter, Hans-Christian; Kirschbaum, Clemens

    2016-01-01

    We tested the hypothesis that a suggestive placebo intervention can reduce the subjective and neurobiological stress response to psychosocial stress. Fifty-four healthy male subjects with elevated levels of trait anxiety were randomly assigned in a 4:4:1 fashion to receive either no treatment (n = 24), a placebo pill (n = 24), or a herbal drug (n = 6) before undergoing a stress test. We repeatedly measured psychological variables as well as salivary cortisol, alpha-amylase, and heart rate variability prior to and following the stress test. The stressor increased subjective stress and anxiety, salivary cortisol, and alpha-amylase, and decreased heart rate variability (all P placebo or no treatment were found. Subjects receiving placebo showed increased wakefulness during the stress test compared with no-treatment controls (P placebo intervention increased alertness, but modulated neither subjective stress and anxiety nor the physiological response to psychosocial stress. © The Author(s) 2015.

  13. Lighting considerations in controlled environments for nonphotosynthetic plant responses to blue and ultraviolet radiation

    Energy Technology Data Exchange (ETDEWEB)

    Caldwell, M.M.; Flint, S.D. [Utah State Univ., Logan, UT (United States)

    1994-12-31

    This essay will consider both physical and photobiological aspects of controlled environment lighting in the spectral region beginning in the blue and taken to the normal limit of the solar spectrum in the ultraviolet. The primary emphasis is directed to questions of plant response to sunlight. Measurement and computations used in radiation dosimetry in this part of the spectrum are also briefly treated. Because of interest in the ozone depletion problem, there has been some activity in plant UV-B research and there are several recent reviews available. Some aspects of growth chamber lighting as it relates to UV-B research were covered earlier. Apart from work related to the blue/UV-A receptor, less attention has been given to UV-A responses.

  14. Molecular control of flowering in response to day length in rice.

    Science.gov (United States)

    Brambilla, Vittoria; Fornara, Fabio

    2013-05-01

    Flowering at the most appropriate times of the year requires careful monitoring of environmental conditions and correct integration of such information with an endogenous molecular network. Rice (Oryza sativa) is a facultative short day plant, and flowers quickly under short day lengths, as opposed to Arabidopsis thaliana whose flowering is accelerated by longer days. Despite these physiological differences, several genes controlling flowering in response to day length (or photoperiod) are conserved between rice and Arabidopsis, and the molecular mechanisms involved are similar. Inductive day lengths trigger expression of florigenic proteins in leaves that can move to the shoot apical meristem to induce reproductive development. As compared to Arabidopsis, rice also possesses unique factors that regulate expression of florigenic genes. Here, we discuss recent advances in understanding the molecular mechanisms involved in day length perception, production of florigenic signals, and molecular responses of the shoot apical meristem to florigenic proteins. © 2013 Institute of Botany, Chinese Academy of Sciences.

  15. Media ion composition controls regulatory and virulence response of Salmonella in spaceflight.

    Directory of Open Access Journals (Sweden)

    James W Wilson

    Full Text Available The spaceflight environment is relevant to conditions encountered by pathogens during the course of infection and induces novel changes in microbial pathogenesis not observed using conventional methods. It is unclear how microbial cells sense spaceflight-associated changes to their growth environment and orchestrate corresponding changes in molecular and physiological phenotypes relevant to the infection process. Here we report that spaceflight-induced increases in Salmonella virulence are regulated by media ion composition, and that phosphate ion is sufficient to alter related pathogenesis responses in a spaceflight analogue model. Using whole genome microarray and proteomic analyses from two independent Space Shuttle missions, we identified evolutionarily conserved molecular pathways in Salmonella that respond to spaceflight under all media compositions tested. Identification of conserved regulatory paradigms opens new avenues to control microbial responses during the infection process and holds promise to provide an improved understanding of human health and disease on Earth.

  16. Mechanical weed control on small-size dry bean and its response to cross-flaming

    Energy Technology Data Exchange (ETDEWEB)

    Martelloni, L.; Frasconi, C.; Fontanelli, M.; Raffaelli, M.; Peruzzi, A.

    2016-11-01

    Dry bean (Phaseolus vulgaris L.) can be a profitable crop for farmers; however controlling weeds effectively without a decrease in yield remains a problem. An example where mechanical weed control is difficult to conduct is dry bean ‘Toscanello’, which is a small sized high-income niche product growing low to the ground. Concerning intra-row weed control, also flame weeding could be an opportunity but the dry bean heat tolerance needs to be studied. The aims of this research were to study the weed control efficacy of a spring-tine harrow and an inter-row cultivator in this bean variety, and to test the tolerance of dry bean cultivated under weed-free conditions to cross-flaming applied with different liquefied petroleum gas (LPG) doses. Flame weeding was applied at BBCH 13 and BBCH 14 bean growth stages by pairs of burners producing direct double flame acting into the intra-row space, with bean plants placed in the middle. The results suggest that the spring-tine harrow used two times at BBCH 13 and 14, respectively, lead to a yield similar to that of the weedy control. The inter-row cultivator could be an opportunity for small-sized dry bean crops producers, enabling them to obtain a similar yield compared to the hand-weeded control. Concerning the bean tolerance to cross-flaming the results showed that bean flamed at BBCH 13 stage had little tolerance to cross-flaming. Bean flamed at BBCH 14 stage was tolerant until an LPG dose of 39 kg/ha, giving yield responses similar to those observed in the non-flamed control. (Author)

  17. Dose-Response of Aerobic Exercise on Cognition: A Community-Based, Pilot Randomized Controlled Trial.

    Science.gov (United States)

    Vidoni, Eric D; Johnson, David K; Morris, Jill K; Van Sciver, Angela; Greer, Colby S; Billinger, Sandra A; Donnelly, Joseph E; Burns, Jeffrey M

    2015-01-01

    Epidemiological studies suggest a dose-response relationship exists between physical activity and cognitive outcomes. However, no direct data from randomized trials exists to support these indirect observations. The purpose of this study was to explore the possible relationship of aerobic exercise dose on cognition. Underactive or sedentary participants without cognitive impairment were randomized to one of four groups: no-change control, 75, 150, and 225 minutes per week of moderate-intensity semi-supervised aerobic exercise for 26-weeks in a community setting. Cognitive outcomes were latent residual scores derived from a battery of 16 cognitive tests: Verbal Memory, Visuospatial Processing, Simple Attention, Set Maintenance and Shifting, and Reasoning. Other outcome measures were cardiorespiratory fitness (peak oxygen consumption) and measures of function functional health. In intent-to-treat (ITT) analyses (n = 101), cardiorespiratory fitness increased and perceived disability decreased in a dose-dependent manner across the 4 groups. No other exercise-related effects were observed in ITT analyses. Analyses restricted to individuals who exercised per-protocol (n = 77) demonstrated that Simple Attention improved equivalently across all exercise groups compared to controls and a dose-response relationship was present for Visuospatial Processing. A clear dose-response relationship exists between exercise and cardiorespiratory fitness. Cognitive benefits were apparent at low doses with possible increased benefits in visuospatial function at higher doses but only in those who adhered to the exercise protocol. An individual’s cardiorespiratory fitness response was a better predictor of cognitive gains than exercise dose (i.e., duration) and thus maximizing an individual’s cardiorespiratory fitness may be an important therapeutic target for achieving cognitive benefits. ClinicalTrials.gov NCT01129115.

  18. Control of crosslinking for tailoring collagen-based scaffolds stability and mechanics.

    Science.gov (United States)

    Davidenko, N; Schuster, C F; Bax, D V; Raynal, N; Farndale, R W; Best, S M; Cameron, R E

    2015-10-01

    We provide evidence to show that the standard reactant concentrations used in tissue engineering to cross-link collagen-based scaffolds are up to 100 times higher than required for mechanical integrity in service, and stability against degradation in an aqueous environment. We demonstrate this with a detailed and systematic study by comparing scaffolds made from (a) collagen from two different suppliers, (b) gelatin (a partially denatured collagen) and (c) 50% collagen-50% gelatin mixtures. The materials were processed, using lyophilisation, to produce homogeneous, highly porous scaffolds with isotropic architectures and pore diameters ranging from 130 to 260 μm. Scaffolds were cross-linked using a carbodiimide treatment, to establish the effect of the variations in crosslinking conditions (down to very low concentrations) on the morphology, swelling, degradation and mechanical properties of the scaffolds. Carbodiimide concentration of 11.5mg/ml was defined as the standard (100%) and was progressively diluted down to 0.1%. It was found that 10-fold reduction in the carbodiimide content led to the significant increase (almost 4-fold) in the amount of free amine groups (primarily on collagen lysine residues) without compromising mechanics and stability in water of all resultant scaffolds. The importance of this finding is that, by reducing cross-linking, the corresponding cell-reactive carboxylate anions (collagen glutamate or aspartate residues) that are essential for integrin-mediated binding remain intact. Indeed, a 10-fold reduction in carbodiimide crosslinking resulted in near native-like cell attachment to collagen scaffolds. We have demonstrated that controlling the degree of cross-linking, and hence retaining native scaffold chemistry, offers a major step forward in the biological performance of collagen- and gelatin-based tissue engineering scaffolds. This work developed collagen and gelatine-based scaffolds with structural, material and biological

  19. The cost of self-protection: threat response and performance as a function of autonomous and controlled motivations.

    Science.gov (United States)

    Hodgins, Holley S; Weibust, Kristin S; Weinstein, Netta; Shiffman, Sara; Miller, Anita; Coombs, Garth; Adair, Kathryn C

    2010-08-01

    Seventy-seven undergraduates, primed for autonomous or controlled motivation, were videotaped and physiologically monitored during a stressful interview and subsequent speech. Interview videotapes were coded for behavioral measures of threat response; speech videotapes were coded for performance. It was hypothesized that relative to controlled motivation, autonomous motivation would decrease interview threat response and enhance speech performance, and that threat response would mediate the effect of motivation on performance. Results support the prediction across measures of verbal, paralinguistic, smiling, vocal fundamental frequency, and cardiovascular response. Autonomously primed participants continued to show less cardiovascular threat throughout the later speech and gave better speeches. Finally, speech performance was mediated by interview threat response. Results demonstrate that relative to controlled motivation, autonomous motivation lowers threat response, which enhances performance.

  20. [Likeness between respiratory responses on CO2 in conditions of natural breathing and voluntary-controlled mechanical ventilation].

    Science.gov (United States)

    Pogodin, M A; Granstrem, M P; Dimitrienko, A I

    2007-04-01

    We did Read CO2 rebreathing tests in 8 adult males. Both at natural breathing, and at self-controlled mechanical ventilation, volunteers increased ventilation proportionally to growth end-tidal PCO2. Inside individual distinctions of responses to CO2 during controlled mechanical ventilation are result of the voluntary motor control.

  1. CCM proteins control endothelial β1 integrin dependent response to shear stress

    Directory of Open Access Journals (Sweden)

    Zuzana Macek Jilkova

    2014-11-01

    Full Text Available Hemodynamic shear stress from blood flow on the endothelium critically regulates vascular function in many physiological and pathological situations. Endothelial cells adapt to shear stress by remodeling their cytoskeletal components and subsequently by changing their shape and orientation. We demonstrate that β1 integrin activation is critically controlled during the mechanoresponse of endothelial cells to shear stress. Indeed, we show that overexpression of the CCM complex, an inhibitor of β1 integrin activation, blocks endothelial actin rearrangement and cell reorientation in response to shear stress similarly to β1 integrin silencing. Conversely, depletion of CCM2 protein leads to an elongated “shear-stress-like” phenotype even in the absence of flow. Taken together, our findings reveal the existence of a balance between positive extracellular and negative intracellular signals, i.e. shear stress and CCM complex, for the control of β1 integrin activation and subsequent adaptation of vascular endothelial cells to mechanostimulation by fluid shear stress.

  2. A Stress Sensor Based on Galvanic Skin Response (GSR Controlled by ZigBee

    Directory of Open Access Journals (Sweden)

    María Viqueira Villarejo

    2012-05-01

    Full Text Available Sometimes, one needs to control different emotional situations which can lead the person suffering them to dangerous situations, in both the medium and short term. There are studies which indicate that stress increases the risk of cardiac problems. In this study we have designed and built a stress sensor based on Galvanic Skin Response (GSR, and controlled by ZigBee. In order to check the device’s performance, we have used 16 adults (eight women and eight men who completed different tests requiring a certain degree of effort, such as mathematical operations or breathing deeply. On completion, we appreciated that GSR is able to detect the different states of each user with a success rate of 76.56%. In the future, we plan to create an algorithm which is able to differentiate between each state.

  3. A Mock Randomized Controlled Trial With Audience Response Technology for Teaching and Learning Epidemiology.

    Science.gov (United States)

    Baker, Philip R A; Francis, Daniel P; Cathcart, Abby

    2017-04-01

    The study's objective was to apply and assess an active learning approach to epidemiology and critical appraisal. Active learning comprised a mock, randomized controlled trial (RCT) conducted with learners in 3 countries. The mock trial consisted of blindly eating red Smarties candy (intervention) compared to yellow Smarties (control) to determine whether red Smarties increase happiness. Audience response devices were employed with the 3-fold purposes to produce outcome data for analysis of the effects of red Smarties, identify baseline and subsequent changes in participant's knowledge and confidence in understanding of RCTs, and assess the teaching approach. Of those attending, 82% (117 of 143 learners) participated in the trial component. Participating in the mock trial was a positive experience, and the use of the technology aided learning. The trial produced data that learners analyzed in "real time" during the class. The mock RCT is a fun and engaging approach to teaching RCTs and helping students to develop skills in critical appraisal.

  4. Agitation predicts response of depression to botulinum toxin treatment in a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Marc Axel Wollmer

    2014-03-01

    Full Text Available In a randomized, controlled trial (n=30 we showed that botulinum toxin injection to the glabellar region produces a marked improvement in the symptoms of major depression. We hypothesized that the mood-lifting effect was mediated by facial feedback mechanisms. Here we assessed if agitation, which may be associated with increased dynamic psychomotor activity of the facial musculature, can predict response to the treatment. To test this hypothesis we re-analyzed the data of the scales from our previous study on a single item basis and compared the baseline scores in the agitation item (item 9 of the Hamilton Depression Rating Scale (HAM-D between responders (n=9 and participants who did not attain response (n=6 among the recipients of onabotulinumtoxinA (n=15. Results: Responders had significantly higher item 9 scores at baseline (1.56+0.88 vs. 0.33+0.52, t(13=3.04, d=1.7, p=0.01, while no other single item of the HAM-D or the Beck Depression Inventory was associated with treatment response. The agitation score had an overall precision of 78% in predicting response in a receiver operating characteristic (ROC analysis (area under the curve, AUC=0.87. These data provide a link between response to botulinum toxin treatment with a psychomotor manifestation of depression and thereby indirect support of the proposed facial feedback mechanism of action. Moreover, it suggests that patients with agitated depression may particularly benefit from botulinum toxin treatment.

  5. Prey-mediated behavioral responses of feeding blue whales in controlled sound exposure experiments.

    Science.gov (United States)

    Friedlaender, A S; Hazen, E L; Goldbogen, J A; Stimpert, A K; Calambokidis, J; Southall, B L

    2016-06-01

    Behavioral response studies provide significant insights into the nature, magnitude, and consequences of changes in animal behavior in response to some external stimulus. Controlled exposure experiments (CEEs) to study behavioral response have faced challenges in quantifying the importance of and interaction among individual variability, exposure conditions, and environmental covariates. To investigate these complex parameters relative to blue whale behavior and how it may change as a function of certain sounds, we deployed multi-sensor acoustic tags and conducted CEEs using simulated mid-frequency active sonar (MFAS) and pseudo-random noise (PRN) stimuli, while collecting synoptic, quantitative prey measures. In contrast to previous approaches that lacked such prey data, our integrated approach explained substantially more variance in blue whale dive behavioral responses to mid-frequency sounds (r2 = 0.725 vs. 0.14 previously). Results demonstrate that deep-feeding whales respond more clearly and strongly to CEEs than those in other behavioral states, but this was only evident with the increased explanatory power provided by incorporating prey density and distribution as contextual covariates. Including contextual variables increases the ability to characterize behavioral variability and empirically strengthens previous findings that deep-feeding blue whales respond significantly to mid-frequency sound exposure. However, our results are only based on a single behavioral state with a limited sample size, and this analytical framework should be applied broadly across behavioral states. The increased capability to describe and account for individual response variability by including environmental variables, such as prey, that drive foraging behavior underscores the importance of integrating these and other relevant contextual parameters in experimental designs. Our results suggest the need to measure and account for the ecological dynamics of predator

  6. Anti-HERV-K (HML-2) capsid antibody responses in HIV elite controllers.

    Science.gov (United States)

    de Mulder, Miguel; SenGupta, Devi; Deeks, Steven G; Martin, Jeffrey N; Pilcher, Christopher D; Hecht, Frederick M; Sacha, Jonah B; Nixon, Douglas F; Michaud, Henri-Alexandre

    2017-08-22

    Human endogenous retroviruses (HERVs) comprise approximately 8% of the human genome and while the majority are transcriptionally silent, the most recently integrated HERV, HERV-K (HML-2), remains active. During HIV infection, HERV-K (HML-2) specific mRNA transcripts and viral proteins can be detected. In this study, we aimed to understand the antibody response against HERV-K (HML-2) Gag in the context of HIV-1 infection. We developed an ELISA assay using either recombinant protein or 164 redundant "15mer" HERV-K (HML-2) Gag peptides to test sera for antibody reactivity. We identified a total of eight potential HERV-K (HML-2) Gag immunogenic domains: two on the matrix (peptides 16 and 31), one on p15 (peptide 85), three on the capsid (peptides 81, 97 and 117), one on the nucleocapsid (peptide 137) and one on the QP1 protein (peptide 157). Four epitopes (peptides 16, 31, 85 and 137) were highly immunogenic. No significant differences in antibody responses were found between HIV infected participants (n = 40) and uninfected donors (n = 40) for 6 out of the 8 epitopes tested. The antibody response against nucleocapsid (peptide 137) was significantly lower (p K (HML-2) capsid recombinant peptide in gamma interferon (IFN-γ) enzyme immunospot (Elispot) assays. We found that the HERV-K (HML-2) Gag antibody and T cell response by Elispot were significantly correlated. HIV elite controllers had a strong cellular and antibody response against HERV-K (HML-2) Gag directed mainly against the Capsid region. Collectively, these data suggest that anti-HERV-K (HML-2) antibodies targeting capsid could have an immunoprotective effect in HIV infection.

  7. Modeling T cell antigen discrimination based on feedback control of digital ERK responses.

    Directory of Open Access Journals (Sweden)

    2005-11-01

    Full Text Available T-lymphocyte activation displays a remarkable combination of speed, sensitivity, and discrimination in response to peptide-major histocompatibility complex (pMHC ligand engagement of clonally distributed antigen receptors (T cell receptors or TCRs. Even a few foreign pMHCs on the surface of an antigen-presenting cell trigger effective signaling within seconds, whereas 1 x 10(5-1 x 10(6 self-pMHC ligands that may differ from the foreign stimulus by only a single amino acid fail to elicit this response. No existing model accounts for this nearly absolute distinction between closely related TCR ligands while also preserving the other canonical features of T-cell responses. Here we document the unexpected highly amplified and digital nature of extracellular signal-regulated kinase (ERK activation in T cells. Based on this observation and evidence that competing positive- and negative-feedback loops contribute to TCR ligand discrimination, we constructed a new mathematical model of proximal TCR-dependent signaling. The model made clear that competition between a digital positive feedback based on ERK activity and an analog negative feedback involving SH2 domain-containing tyrosine phosphatase (SHP-1 was critical for defining a sharp ligand-discrimination threshold while preserving a rapid and sensitive response. Several nontrivial predictions of this model, including the notion that this threshold is highly sensitive to small changes in SHP-1 expression levels during cellular differentiation, were confirmed by experiment. These results combining computation and experiment reveal that ligand discrimination by T cells is controlled by the dynamics of competing feedback loops that regulate a high-gain digital amplifier, which is itself modulated during differentiation by alterations in the intracellular concentrations of key enzymes. The organization of the signaling network that we model here may be a prototypic solution to the problem of achieving

  8. Effects of pressure-controlled and volume-controlled ventilation on respiratory mechanics and systemic stress response during laparoscopic cholecystectomy.

    Science.gov (United States)

    Sen, Oznur; Umutoglu, Tarik; Aydın, Nurdan; Toptas, Mehmet; Tutuncu, Ayse Cigdem; Bakan, Mefkur

    2016-01-01

    Pressure-controlled ventilation (PCV) is less frequently employed in general anesthesia. With its high and decelerating inspiratory flow, PCV has faster tidal volume delivery and different gas distribution. The same tidal volume setting, delivered by PCV versus volume-controlled ventilation (VCV), will result in a lower peak airway pressure and reduced risk of barotrauma. We hypothesized that PCV instead of VCV during laparoscopic surgery could achieve lower airway pressures and reduce the systemic stress response. Forty ASA I-II patients were randomly selected to receive either the PCV (Group PC, n = 20) or VCV (Group VC, n = 20) during laparoscopic cholecystectomy. Blood sampling was made for baseline arterial blood gases (ABG), cortisol, insulin, and glucose levels. General anesthesia with sevoflurane and fentanyl was employed to all patients. After anesthesia induction and endotracheal intubation, patients in Group PC were given pressure support to form 8 mL/kg tidal volume and patients in Group VC was maintained at 8 mL/kg tidal volume calculated using predicted body weight. All patients were maintained with 5 cmH2O positive-end expiratory pressure (PEEP). Respiratory parameters were recorded before and 30 min after pneumoperitonium. Assessment of ABG and sampling for cortisol, insulin and glucose levels were repeated 30 min after pneumoperitonium and 60 min after extubation. The P-peak levels observed before (18.9 ± 3.8 versus 15 ± 2.2 cmH2O) and during (23.3 ± 3.8 versus 20.1 ± 2.9 cmH2O) pneumoperitoneum in Group VC were significantly higher. Postoperative partial arterial oxygen pressure (PaO2) values are higher (98 ± 12 versus 86 ± 11 mmHg) in Group PC. Arterial carbon dioxide pressure (PaCO2) values (41.8 ± 5.4 versus 36.7 ± 3.5 mmHg) during pneumoperitonium and post-operative mean cortisol and insulin levels were higher in Group VC. When compared to VCV mode, PCV mode may improve compliance during pneumoperitoneum

  9. Electrophysiological indices of response inhibition in a Go/NoGo task predict self-control in a social context.

    Directory of Open Access Journals (Sweden)

    Kyle Nash

    Full Text Available Recent research demonstrates that response inhibition-a core executive function-may subserve self-regulation and self-control. However, it is unclear whether response inhibition also predicts self-control in the multifaceted, high-level phenomena of social decision-making. Here we examined whether electrophysiological indices of response inhibition would predict self-control in a social context. Electroencephalography was recorded as participants completed a widely used Go/NoGo task (the cued Continuous Performance Test. Participants then interacted with a partner in an economic exchange game that requires self-control. Results demonstrated that greater NoGo-Anteriorization and larger NoGo-P300 peak amplitudes-two established electrophysiological indices of response inhibition-both predicted more self-control in this social game. These findings support continued integration of executive function and self-regulation and help extend prior research into social decision-making processes.

  10. Association between Responsible Pet Ownership and Glycemic Control in Youths with Type 1 Diabetes.

    Science.gov (United States)

    Maranda, Louise; Gupta, Olga T

    2016-01-01

    Type 1 diabetes mellitus (T1DM) a chronic characterized by an absolute insulin deficiency requires conscientious patient self-management to maintain glucose control within a normal range. Family cohesion and adaptability, positive coping strategies, social support and adequate self-regulatory behavior are found to favorably influence glycemic control. Our hypothesis was that the responsible care of a companion animal is associated with these positive attributes and correlated with the successful management of a chronic illness such as type 1 diabetes. We recruited 223 youths between 9 and 19 years of age from the Pediatric Diabetes clinic at the University of Massachusetts Medical School, reviewed the status of their glycemic control (using three consecutive A1c values) and asked them questions about the presence of a pet at home, and their level of involvement with its care. Multivariate analyses show that children who care actively for one or more pets at home are 2.5 times more likely to have control over their glycemic levels than children who do not care for a pet, adjusting for duration of disease, socio-economic status, age and self-management [1.1 to 5.8], pWald = 0.032. A separate model involving the care of a petdog only yielded comparable results (ORa = 2.6 [1.1 to 5.9], pWald = 0.023).

  11. Association between Responsible Pet Ownership and Glycemic Control in Youths with Type 1 Diabetes.

    Directory of Open Access Journals (Sweden)

    Louise Maranda

    Full Text Available Type 1 diabetes mellitus (T1DM a chronic characterized by an absolute insulin deficiency requires conscientious patient self-management to maintain glucose control within a normal range. Family cohesion and adaptability, positive coping strategies, social support and adequate self-regulatory behavior are found to favorably influence glycemic control. Our hypothesis was that the responsible care of a companion animal is associated with these positive attributes and correlated with the successful management of a chronic illness such as type 1 diabetes. We recruited 223 youths between 9 and 19 years of age from the Pediatric Diabetes clinic at the University of Massachusetts Medical School, reviewed the status of their glycemic control (using three consecutive A1c values and asked them questions about the presence of a pet at home, and their level of involvement with its care. Multivariate analyses show that children who care actively for one or more pets at home are 2.5 times more likely to have control over their glycemic levels than children who do not care for a pet, adjusting for duration of disease, socio-economic status, age and self-management [1.1 to 5.8], pWald = 0.032. A separate model involving the care of a petdog only yielded comparable results (ORa = 2.6 [1.1 to 5.9], pWald = 0.023.

  12. How do location and control over the music influence listeners' responses?

    Science.gov (United States)

    Krause, Amanda E; North, Adrian C

    2017-04-01

    This study uses Mehrabian and Russell's () Pleasure-Arousal-Dominance (PAD) model to consider how responses to both the music heard and overall in-situ listening experience are influenced by the listener's degree of control over music selected for a particular listening episode and the location in which the listening takes place. Following recruitment via campus advertisements and a university research participation program, 216 individuals completed a background questionnaire and music listening task in a 3 (location) × 2 (experimenter- or participant-selected music) design. After the listening task, participants completed a short questionnaire concerning the music they heard and the overall in-situ listening experience. Results demonstrated that there was a positive relationship between control and liking for the music and episode, whether the former was considered in terms of: (1) whether the music was self-selected or experimenter-selected or (2) overt ratings of perceived control. Furthermore, the location and liking for the music were related to people's judgments of their enjoyment of the overall experience. This research indicates that the PAD model is a useful framework for understanding everyday music listening and supports the contention that, in a musical context, dominance may be operationalized as control over the music. © 2017 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

  13. Effects of music on physiological and behavioral responses of premature infants: a randomized controlled trial.

    Science.gov (United States)

    Alipour, Zahra; Eskandari, Narges; Ahmari Tehran, Hoda; Eshagh Hossaini, Seyed Kamal; Sangi, Sareh

    2013-08-01

    Despite persuasive theories about the beneficial effects of music and singing in developmental care for premature infants, few small studies are available in this regard. We conducted this study to investigate the physiological and behavioral responses of premature infants to recorded lullaby music and silence. In a randomized controlled trial, 90 premature infants in the neonatal care unit of a hospital in Qom (Iran) were randomly allocated to intervention (lullaby and silence) or control groups. Lullaby music was played via headphones at a volume of 50-60 dB. In the silence group, headphones were placed on the infants' ears while no music was played. The three groups were surveyed for physiological responses including oxygen saturation, respiratory and heart rates, and behavioral states every five minutes before, during, and after the intervention. The three groups were not significantly different in terms of mean values of respiratory and heart rates, oxygen saturation, and behavioral states of infants. Similarly, no significant within group differences in respiratory and heart rates, oxygen saturation, and behavioral states were observed at different times. Our findings did not support the beneficial effects of music for premature infants. However, music is a noninvasive, non-pharmaceutical, and relatively low-cost intervention that can be implemented at infants' bedside. Thus further research is warranted to determine whether the effects noted in previous studies can be consistently replicated in diverse settings and with diverse groups of preterm infants. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. [Response and Control Factors of Groundwater to Extreme Weather, Jiguan Cave, Henan Province, China].

    Science.gov (United States)

    Liu, Xiao; Yang, Yan; Peng, Tao; Zhao, Jing-yao; Ren, Xiao-feng; Zhang, Yin-huan; Nie Xu-dong; Li, Jian-cang; Ling, Xin-you; Zhang, Zhi-qin

    2015-05-01

    Geochemical dynamics of cave water were monitored to unveil its variation and controlling factors from October 2009 to December 2013 in Jiguan Cave,west of Henan province,southeastern coast of the loess plateau. The results showed that: (1) the hydrochemical types of the cave water are HCO(3-)-Ca(2+)-Mg2+ and HCO(3-)-Mg(2+)-Ca2+. HCO(3-) are over 80% of the anions, Ca2+ and Mg2+ are the dominate cations, and ground river keeping in erosion and pool water drips in deposition all the year. (2) Dripping water and pool water in Ji guan cave can respond perfectly to the change of external climate environment, which geochemistry indexes possess the extraordinary seasonal effects. (3) The concentration changes of the Ca2+, Mg2+ , SO4(2-) responded sensitively to annual precipitation change. Ca2+, Mg2+, SO4(2-) rise in waterlogging year and fall in drought year. Because HCO(3-) controlled by CO2 concentration. HCO(3-) concentration showed a unconspicuous response to the change of external climate environment. (4) The concentration changes of Ca2+, Mg2+, SO4(2-) have no obvious seasonal variation and showed a unconspicuous response to the change of external climate environment.

  15. Demand Response Advanced Controls Framework and Assessment of Enabling Technology Costs

    Energy Technology Data Exchange (ETDEWEB)

    Potter, Jennifer; Cappers, Peter

    2017-08-28

    The Demand Response Advanced Controls Framework and Assessment of Enabling Technology Costs research describe a variety of DR opportunities and the various bulk power system services they can provide. The bulk power system services are mapped to a generalized taxonomy of DR “service types”, which allows us to discuss DR opportunities and bulk power system services in fewer yet broader categories that share similar technological requirements which mainly drive DR enablement costs. The research presents a framework for the costs to automate DR and provides descriptions of the various elements that drive enablement costs. The report introduces the various DR enabling technologies and end-uses, identifies the various services that each can provide to the grid and provides the cost assessment for each enabling technology. In addition to a report, this research includes a Demand Response Advanced Controls Database and User Manual. They are intended to provide users with the data that underlies this research and instructions for how to use that database more effectively and efficiently.

  16. pH-Responsive PLGA Nanoparticle for Controlled Payload Delivery of Diclofenac Sodium

    Directory of Open Access Journals (Sweden)

    Shalil Khanal

    2016-08-01

    Full Text Available Poly(lactic-co-glycolic acid (PLGA based nanoparticles have gained increasing attention in delivery applications due to their capability for controlled drug release characteristics, biocompatibility, and tunable mechanical, as well as degradation, properties. However, thorough study is always required while evaluating potential toxicity of the particles from dose dumping, inconsistent release and drug-polymer interactions. In this research, we developed PLGA nanoparticles modified by chitosan (CS, a cationic and pH responsive polysaccharide that bears repetitive amine groups in its backbone. We used a model drug, diclofenac sodium (DS, a nonsteroidal anti-inflammatory drug (NSAID, to study the drug loading and release characteristics. PLGA nanoparticles were synthesized by double-emulsion solvent evaporation technique. The nanoparticles were evaluated based on their particle size, surface charge, entrapment efficacy, and effect of pH in drug release profile. About 390–420 nm of average diameters and uniform morphology of the particles were confirmed by scanning electron microscope (SEM imaging and dynamic light scattering (DLS measurement. Chitosan coating over PLGA surface was confirmed by FTIR and DLS. Drug entrapment efficacy was up to 52%. Chitosan coated PLGA showed a pH responsive drug release in in vitro. The release was about 45% more at pH 5.5 than at pH 7.4. The results of our study indicated the development of chitosan coating over PLGA nanoparticle for pH dependent controlled release DS drug for therapeutic applications.

  17. Cellular responses to a prolonged delay in mitosis are determined by a DNA damage response controlled by Bcl-2 family proteins.

    Science.gov (United States)

    Colin, Didier J; Hain, Karolina O; Allan, Lindsey A; Clarke, Paul R

    2015-03-01

    Anti-cancer drugs that disrupt mitosis inhibit cell proliferation and induce apoptosis, although the mechanisms of these responses are poorly understood. Here, we characterize a mitotic stress response that determines cell fate in response to microtubule poisons. We show that mitotic arrest induced by these drugs produces a temporally controlled DNA damage response (DDR) characterized by the caspase-dependent formation of γH2AX foci in non-apoptotic cells. Following exit from a delayed mitosis, this initial response results in activation of DDR protein kinases, phosphorylation of the tumour suppressor p53 and a delay in subsequent cell cycle progression. We show that this response is controlled by Mcl-1, a regulator of caspase activation that becomes degraded during mitotic arrest. Chemical inhibition of Mcl-1 and the related proteins Bcl-2 and Bcl-xL by a BH3 mimetic enhances the mitotic DDR, promotes p53 activation and inhibits subsequent cell cycle progression. We also show that inhibitors of DDR protein kinases as well as BH3 mimetics promote apoptosis synergistically with taxol (paclitaxel) in a variety of cancer cell lines. Our work demonstrates the role of mitotic DNA damage responses in determining cell fate in response to microtubule poisons and BH3 mimetics, providing a rationale for anti-cancer combination chemotherapies.

  18. Performance indicators for initial regional medical response to major incidents: a possible quality control tool

    Directory of Open Access Journals (Sweden)

    Nilsson Heléne

    2012-12-01

    Full Text Available Abstract Background Timely decisions concerning mobilization and allocation of resources and distribution of casualties are crucial in medical management of major incidents. The aim of this study was to evaluate documented initial regional medical responses to major incidents by applying a set of 11 measurable performance indicators for regional medical command and control and test the feasibility of the indicators. Methods Retrospective data were collected from documentation from regional medical command and control at major incidents that occurred in two Swedish County Councils. Each incident was assigned to one of nine different categories and 11 measurable performance indicators for initial regional medical command and control were systematically applied. Two-way analysis of variance with one observation per cell was used for statistical analysis and the post hoc Tukey test was used for pairwise comparisons. Results The set of indicators for regional medical command and control could be applied in 102 of the130 major incidents (78%, but 36 incidents had to be excluded due to incomplete documentation. The indicators were not applicable as a set for 28 incidents (21.5% due to different characteristics and time frames. Based on the indicators studied in 66 major incidents, the results demonstrate that the regional medical management performed according to the standard in the early phases (1–10 min after alert, but there were weaknesses in the secondary phase (10–30 min after alert. The significantly lowest scores were found for Indicator 8 (formulate general guidelines for response and Indicator 10 (decide whether or not resources in own organization are adequate. Conclusions Measurable performance indicators for regional medical command and control can be applied to incidents that directly or indirectly involve casualties provided there is sufficient documentation available. Measurable performance indicators can enhance follow- up and be

  19. Electrically responsive microreservoires for controllable delivery of dexamethasone in bone tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Paun, Irina Alexandra, E-mail: irina.paun@physics.pub.ro [Faculty of Applied Sciences, University Politehnica of Bucharest, RO-060042 (Romania); National Institute for Laser, Plasma and Radiation Physics, Magurele, Bucharest RO-077125 (Romania); Zamfirescu, Marian [National Institute for Laser, Plasma and Radiation Physics, Magurele, Bucharest RO-077125 (Romania); Luculescu, Catalin Romeo, E-mail: catalin.luculescu@inflpr.ro [National Institute for Laser, Plasma and Radiation Physics, Magurele, Bucharest RO-077125 (Romania); Acasandrei, Adriana Maria; Mustaciosu, Cosmin Catalin [Horia Hulubei National Institute for Physics and Nuclear Engineering IFIN-HH, Magurele, Bucharest RO-077125 (Romania); Mihailescu, Mona [Faculty of Applied Sciences, University Politehnica of Bucharest, RO-060042 (Romania); Dinescu, Maria, E-mail: dinescum@nipne.ro [National Institute for Laser, Plasma and Radiation Physics, Magurele, Bucharest RO-077125 (Romania)

    2017-01-15

    Highlights: • Electrically-responsive microreservoires (ERRs) for controlled release of Dex. • ERRs made of microtubes produced by two photon polymerization of IP-L780 photoresist. • Microtubes loaded with PPy/Dex mixture and sealed with a thin PLGA layer. • Kinetics of Dex release controlled by electrical stimulation of the ERRs. • Controlled Dex release accelerates the cells osteogenic differentiation. - Abstract: A major concern in orthopedic implants is to decrease the chronic inflammation using specific drug therapies. The newest strategies rely on the controlled delivery of antiinflammatory drugs from carrier biointerfaces designed in the shape of 3D architectures. We report on electrically responsive microreservoires (ERRs) acting as microcontainers for antiinflammatory drugs, as potential biointerfaces in orthopedic implants. The ERRs consist in arrays of vertical microtubes produced by laser direct writing using two photon polymerization effects (2PP-LDW) of a commercially available photoresist, IP-L780. A polypyrrole (conductive)/dexamethasone (drug model) (PPy/Dex) mixture was loaded into the ERRs via a simple immersion process. Then, the ERRs were sealed with a poly(lactic-co-glycolic acid)(PLGA) layer by Matrix Assisted Pulsed Laser Evaporation. ERRs stimulation using voltage cycles between −1 V and +1 V, applied at specific time intervals, at a scan rate of 0.1 V s{sup −1}, enabled to control the Dex release. The release time scales were between 150 and 275 h, while the concentrations of Dex released were between 450–460 nM after three applied voltage cycles, for different microreservoires dimensions. The proposed approach was validated in osteoblast-like MG-63 cell cultures. Cell viability and adhesion assays showed that the Dex-loaded ERRs sustained the cells growth and preserved their characteristic polygonal shape. Importantly, for the electrically-stimulated Dex release, the level of the alkaline phosphatase activity increased

  20. Thermo-responsive polymer-functionalized mesoporous carbon for controlled drug release

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Shenmin, E-mail: smzhu@sjtu.edu.cn [State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); Chen Chenxin [State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); Chen Zhixin [Faculty of Engineering, University of Wollongong, Wollongong, NSW 2522 (Australia); Liu Xinye; Li Yao; Shi Yang; Zhang Di [State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China)

    2011-03-15

    Research highlights: {yields} A responsive drug delivery system based on poly(N-isopropyl acrylamide) (PNIPAM) functionalized ordered mesoporous carbon (CMK-3) is developed. {yields} A combination of surface modification of CMK-3 and in situ internal polymerization of PNIPAM was used. {yields} The system exhibited a pronounced transition at around 20-25 deg. C. - Abstract: A novel responsive drug delivery system based on poly(N-isopropyl acrylamide) (PNIPAM) functionalized ordered mesoporous carbon (CMK-3) is developed. The polymer-functionalized CMK-3 was obtained by a combination of simple surface modification of CMK-3 and in situ internal polymerization of PNIPAM. The formation of the PNIPAM inside the CMK-3 was confirmed by thermal gravimetric analysis, Fourier transform-infrared spectroscopy, scanning and transmission electron microscopy and N{sub 2} adsorption/desorption measurements. Controlled drug release tests through the porous network of the PNIPAM functionalized CMK-3 were carried out by measuring the uptake and release of ibuprofen in vitro. The release profiles exhibited a pronounced transition at around 20-25 deg. C. This thermo-sensitive release property of this delivery system was further confirmed by temperature-variable hydrogen nuclear magnetic resonance analysis. The internal PNIPAM layers acted as a storage gate as well as a release switch in response to the stimuli of environment.

  1. Applicability to foraging simulation of a reinforcement schedule controlling the response energy of pigeons.

    Science.gov (United States)

    Kono, Masanori

    2013-12-01

    In optimal foraging theory (OFT), energy expenditure is an important variable for predicting foraging behavior. However, early studies, including operant simulations of foraging, did not measure energy expenditure. In the present study, an adjusting energy (AE) schedule was developed to control energy expenditure. Interresponse energy (IRE), a measure of the energy expenditure during a response, was calculated by dividing the square of the elapsed time between two consecutive responses by the square of the straight-line distance between the locations of the same two responses. An adjusting procedure was employed to estimate the indifference point between the requirements of the AE schedule and a fixed ratio (FR) schedule, which has been used in many operant simulations. In the adjusting procedure, pigeons adjusted the requirement of the AE schedule to that of the FR schedule. The results showed a systematic relationship between the requirements of the AE and FR schedules. Moreover, the total IRE per reinforcement systematically increased with the AE requirement. Thus, the present study demonstrates the utility of the AE schedule as a procedure for testing the validity of OFT.

  2. Dissecting dynamic genetic variation that controls temporal gene response in yeast.

    Directory of Open Access Journals (Sweden)

    Avital Brodt

    2014-12-01

    Full Text Available Inter-individual variation in regulatory circuits controlling gene expression is a powerful source of functional information. The study of associations among genetic variants and gene expression provides important insights about cell circuitry but cannot specify whether and when potential variants dynamically alter their genetic effect during the course of response. Here we develop a computational procedure that captures temporal changes in genetic effects, and apply it to analyze transcription during inhibition of the TOR signaling pathway in segregating yeast cells. We found a high-order coordination of gene modules: sets of genes co-associated with the same genetic variant and sharing a common temporal genetic effect pattern. The temporal genetic effects of some modules represented a single state-transitioning pattern; for example, at 10-30 minutes following stimulation, genetic effects in the phosphate utilization module attained a characteristic transition to a new steady state. In contrast, another module showed an impulse pattern of genetic effects; for example, in the poor nitrogen sources utilization module, a spike up of a genetic effect at 10-20 minutes following stimulation reflected inter-individual variation in the timing (rather than magnitude of response. Our analysis suggests that the same mechanism typically leads to both inter-individual variation and the temporal genetic effect pattern in a module. Our methodology provides a quantitative genetic approach to studying the molecular mechanisms that shape dynamic changes in transcriptional responses.

  3. Improvement of Torque Response and Examination of Sensorless Drive System Based on Direct Torque Control for IPMSM

    Science.gov (United States)

    Inoue, Yukinori; Morimoto, Shigeo; Sanada, Masayuki

    This paper examines the sensorless control system based on the direct torque control (DTC) for an interior permanent magnet synchronous motor (IPMSM). In the DTC system, the rotor position is not required, and the rotor speed is estimated from the estimated position of stator flux-linkage vector. In addition, the maximum torque per ampere (MTPA) control and the flux weakening (FW) control can be applied to the DTC as well as the current control method in the d-q reference frame. Therefore the DTC can operate over a wide speed range. The characteristic of the maximum power operation is shown by the experimental result. The torque response is investigated by the simulation and experimental results. A relationship between the controller gain and torque response is shown, and an improvement method of the torque response is proposed.

  4. Differential impact of the cheese matrix on the postprandial lipid response: a randomized, crossover, controlled trial.

    Science.gov (United States)

    Drouin-Chartier, Jean-Philippe; Tremblay, André J; Maltais-Giguère, Julie; Charest, Amélie; Guinot, Léa; Rioux, Laurie-Eve; Labrie, Steve; Britten, Michel; Lamarche, Benoît; Turgeon, Sylvie L; Couture, Patrick

    2017-12-01

    Background: In a simulated gastrointestinal environment, the cheese matrix modulates dairy fat digestion. However, to our knowledge, the impact of the cheese matrix on postprandial lipemia in humans has not yet been evaluated.Objective: In healthy subjects, we compared the impact of dairy fat provided from firm cheese, soft cream cheese, and butter on the postprandial response at 4 h and on the incremental area under the curve (iAUC) of plasma triglycerides.Design: Forty-three healthy subjects were recruited to this randomized, crossover, controlled trial. In random order at intervals of 14 d and after a 12-h fast, subjects ingested 33 g fat from a firm cheese (young cheddar), a soft cream cheese (cream cheese), or butter (control) incorporated into standardized meals that were matched for macronutrient content. Plasma concentrations of triglycerides were measured immediately before the meal and 2, 4, 6, and 8 h after the meal.Results: Cheddar cheese, cream cheese, and butter induced similar increases in triglyceride concentrations at 4 h (change from baseline: +59%, +59%, and +62%, respectively; P = 0.9). No difference in the triglyceride iAUC0-8 h (P-meal = 0.9) was observed between the 3 meals. However, at 2 h, the triglyceride response caused by the cream cheese (change from baseline: +44%) was significantly greater than that induced by butter (change from baseline: +24%; P = 0.002) and cheddar cheese (change from baseline: +16%; P = 0.0004). At 6 h, the triglyceride response induced by cream cheese was significantly attenuated compared with that induced by cheddar cheese (change from baseline: +14% compared with +42%; P = 0.0004).Conclusion: This study demonstrates that the cheese matrix modulates the impact of dairy fat on postprandial lipemia in healthy subjects. This trial was registered at clinicaltrials.gov as NCT02623790. © 2017 American Society for Nutrition.

  5. Response of molars and non-molars to a strict supragingival control in periodontal patients

    Directory of Open Access Journals (Sweden)

    Patrícia Daniela Melchiors Angst

    2013-02-01

    Full Text Available The posterior position in the arches is one of the factors that underlies the poor prognosis of molar teeth (M. It is speculated that M do not benefit from the oral hygiene routine as well as non-molars (NM do. This study evaluated the response of M and NM to supragingival control during a 6-month period in 25 smokers (S and 25 never-smokers (NS with moderate-to-severe periodontitis. One calibrated examiner assessed visible plaque (VPI and gingival bleeding (GBI indexes, periodontal probing depth (PPD, bleeding on probing (BOP, and clinical attachment loss (CAL at days 0 (baseline, 30 and 180. At baseline, M showed significantly higher mean values of VPI (p = 0.017 and PPD (p < 0.001 compared with NM; CAL was also greater in M (p < 0.001 and was affected by smoking (p = 0.007. The reductions obtained for periodontal indicators at day 180 showed similar responses between M and NM. For CAL, M (NS 0.57 ± 0.50; S 0.67 ± 0.64 and NM (NS 0.38 ± 0.23; S 0.50 ± 0.33 reached an almost significant difference (p = 0.05. Smoking did not influence the response to treatment. Multilevel analysis revealed that, only for PDD reductions, the interaction between sites, teeth and patient was significant (p < 0.001. It was concluded that M benefit from an adequate regimen of supragingival biofilm control; therefore, supragingival condition should be considered in the prognosis of molar teeth.

  6. Impact of alcohol use on EEG dynamics of response inhibition: a cotwin control analysis.

    Science.gov (United States)

    Harper, Jeremy; Malone, Stephen M; Iacono, William G

    2016-11-18

    Research indicates that alcohol misuse is associated with behavioral disinhibition, but the neurophysiological mechanisms governing this relationship remain largely unknown. Recent work suggests that successful inhibition and cognitive control involve electrophysiological theta-band dynamics, including medial frontal cortex (MFC) power enhancement and functional connectivity between the MFC and dorsal prefrontal cortex (dPFC) regions, which may be disrupted by alcohol misuse. In addition, research suggests that, compared to men, women are at heightened risk of experiencing the negative physical and neurocognitive correlates of drinking. The present study tested the hypothesis that alcohol misuse has a deleterious effect on theta-band response inhibition EEG dynamics in a sample of 300 24-year-old same-sex twins. A cotwin control (CTC) design was used to disentangle premorbid risk for alcohol use from the causal effects of alcohol exposure. Drinking was negatively associated with theta-band MFC power and MFC-dPFC connectivity during response inhibition, and this effect was stronger among women. The CTC analysis suggested that, for women, reduced nogo-related theta-band MFC power and MFC-dPFC connectivity were both consistent with the potential deleterious causal effects of alcohol exposure. These findings suggest that diminished theta-band MFC power and MFC-dPFC connectivity may be neurophysiological mechanisms underlying alcohol-related disinhibition. Although preliminary, these results suggest that normative levels of alcohol use during emerging adulthood have potential sex-specific causal effects on response inhibition EEG dynamics, and thus have potentially significant public health implications. © 2016 Society for the Study of Addiction.

  7. Performance of a Single Liquid Column Damper for the Control of Dynamic Responses of a Tension Leg Platform

    Science.gov (United States)

    Jaksic, V.; Wright, C.; Chanayil, Afeef; Faruque Ali, Shaikh; Murphy, Jimmy; Pakrashi, Vikram

    2015-07-01

    Tuned liquid column dampers have been proved to be successful in mitigating the dynamic responses of civil infrastructure. There have been some recent applications of this concept on wind turbines and this passive control system can help to mitigate responses of offshore floating platforms and wave devices. The control of dynamic responses of these devices is important for reducing loads on structural elements and facilitating operations and maintenance (O&M) activities. This paper outlines the use of a tuned single liquid column damper for the control of a tension leg platform supported wind turbine. Theoretical studies were carried out and a scaled model was tested in a wave basin to assess the performance of the damper. The tests on the model presented in this paper correspond to a platform with a very low natural frequency for surge, sway and yaw motions. For practical purposes, it was not possible to tune the liquid damper exactly to this frequency. The consequent approach taken and the efficiency of such approach are presented in this paper. Responses to waves of a single frequency are investigated along with responses obtained from wave spectra characterising typical sea states. The extent of control is quantified using peak and root mean squared dynamic responses respectively. The tests present some guidelines and challenges for testing scaled devices in relation to including response control mechanisms. Additionally, the results provide a basis for dictating future research on tuned liquid column damper based control on floating platforms.

  8. Fast Response Three Phase Induction Motor Using Indirect Field Oriented Control (IFOC Based On Fuzzy-Backstepping

    Directory of Open Access Journals (Sweden)

    Rizana Fauzi

    2015-06-01

    Full Text Available Induction Motor in Electrical drive system at a accelleration speed for example in electric cars have a hard speed setting is set on a wide range, causing an inconvenience for motorists and a fast response is required any change of speed. It is necessary for good system performance in control motor speed and torque at low speed or fast speed response, which is operated by Indirect Field Oriented Control (IFOC. Speed control on IFOC methods should be better to improving the performance of rapid response in the induction motor. In this paper presented a method of incorporation of Fuzzy Logic Controller and Backstepping (Fuzzy-Backstepping to improve the dynamically response speed and torque in Induction Motor on electric car, so we get smoothness at any speed change and braking as well as maximum torque of induction motor. Test results showed that Fuzzy-Backstepping can increase the response to changes speed in electric car. System testing is done with variations of the reference point setting speed control system, the simulation results of the research showed that the IFOC method is not perfect in terms of induction motor speed regulation if it’s not use speed control. Fuzzy-Backstepping control is needed which can improve the response of output, so that the induction motor has a good performance, small oscillations when start working up to speed reference. Keywords: Fuzzy-Backstepping, IFOC, induction motor

  9. Effect of Vibration on Pain Response to Heel Lance: A Pilot Randomized Control Trial.

    Science.gov (United States)

    McGinnis, Kate; Murray, Eileen; Cherven, Brooke; McCracken, Courtney; Travers, Curtis

    2016-12-01

    Applied mechanical vibration in pediatric and adult populations has been shown to be an effective analgesic for acute and chronic pain, including needle pain. Studies among the neonatal population are lacking. According to the Gate Control Theory, it is expected that applied mechanical vibration will have a summative effect with standard nonpharmacologic pain control strategies, reducing behavioral and physiologic pain responses to heel lancing. To determine the safety and efficacy of mechanical vibration for relief of heel lance pain among neonates. In this parallel design randomized controlled trial, eligible enrolled term or term-corrected neonates (n = 56) in a level IV neonatal intensive care unit were randomized to receive either sucrose and swaddling or sucrose, swaddling, and vibration for heel lance analgesia. Vibration was applied using a handheld battery-powered vibrator (Norco MiniVibrator, Hz = 92) to the lateral aspect of the lower leg along the sural dermatome throughout the heel lance procedure. Neonatal Pain, Agitation, and Sedation Scale (N-PASS) scores, heart rate, and oxygen saturations were collected at defined intervals surrounding heel lancing. Infants in the vibration group (n = 30) had significantly lower N-PASS scores and more stable heart rates during heel stick (P = .006, P = .037) and 2 minutes after heel lance (P = .002, P = .016) than those in the nonvibration group. There were no adverse behavioral or physiologic responses to applied vibration in the sample. Applied mechanical vibration is a safe and effective method for managing heel lance pain. This pilot study suggests that mechanical vibration warrants further exploration as a nonpharmacologic pain management tool among the neonatal population.

  10. Adipocytokine responses to acute exercise in athletes with different body fat content and sedentary controls

    Directory of Open Access Journals (Sweden)

    Mirjana Sumarac Dumanovic

    2016-10-01

    Full Text Available Introduction: Recent research in the biology of adipose tissue indicates that it is far more than a simply an energy storage organ, and it is in fact an active endocrine organ secreting numerous bioactive mediators, called adipokines, including leptin, adiponectin and visfatin (Galic, 2010. To date, less attention has been focused on the kinetics of adipokines levels during and after high intensity exercise. Several reports pointed at the metabolic role of adipokines during exercise in elite athletes, but the data are currently equivocal (Bouassida et al., 2010; Jürimäe et al., 2011. Objectives: The aim of this study was to investigate adipocytokine responses to a single bout acute exercise in elite athletes with low percentage of body fat, elite athletes with a high percentage of body fat and sedentary controls. Methods: Sixteen athletes with low percentage of body fat (volleyball players, low fat athletes group, LFAG, fifteen athletes with high percentage of body fat (water polo players, high fat athletes group, HFAG and fifteen sedentary subjects participated in this study (age [years] 20±2; 20±2; 20±1, respectively. All subjects were exposed to: anthropometric measurements; exercise test on treadmill in order to examine acute changes of adipocytokines; blood samples were obtained at baseline levels, immediately after the exercise test and 30 minutes after recovery. Separated serum or plasma were used for hormone (leptin, adiponectin and visfatin ELISA analysis. Results: In athletes in LFAG, baseline leptin concentration was significantly lower, but adiponectin and visfatin concentrations were significantly higher, compared to sedentary controls and athletes in HFAG (p0.05. Conclusions: Our findings show leptin and visfatin levels, but not adiponectin respond to acute exercise. Acute exercise elicited an inverse visfatin response in athletes in HFAG and controls. Also, these results suggest that leptin is altered after acute exercise

  11. A randomized controlled trial of Pivotal Response Treatment Group for parents of children with autism.

    Science.gov (United States)

    Hardan, Antonio Y; Gengoux, Grace W; Berquist, Kari L; Libove, Robin A; Ardel, Christina M; Phillips, Jennifer; Frazier, Thomas W; Minjarez, Mendy B

    2015-08-01

    With rates of autism diagnosis continuing to rise, there is an urgent need for effective and efficient service delivery models. Pivotal Response Treatment (PRT) is considered an established treatment for autism spectrum disorder (ASD); however, there have been few well-controlled studies with adequate sample size. The aim of this study was to conduct a randomized controlled trial to evaluate PRT parent training group (PRTG) for targeting language deficits in young children with ASD. Fifty-three children with autism and significant language delay between 2 and 6 years old were randomized to PRTG (N = 27) or psychoeducation group (PEG; N = 26) for 12 weeks. The PRTG taught parents behavioral techniques to facilitate language development. The PEG taught general information about ASD (clinical trial NCT01881750; http://www.clinicaltrials.gov). Analysis of child utterances during the structured laboratory observation (primary outcome) indicated that, compared with children in the PEG, children in the PRTG demonstrated greater improvement in frequency of utterances (F(2, 43) = 3.53, p = .038, d = 0.42). Results indicated that parents were able to learn PRT in a group format, as the majority of parents in the PRTG (84%) met fidelity of implementation criteria after 12 weeks. Children also demonstrated greater improvement in adaptive communication skills (Vineland-II) following PRTG and baseline Mullen visual reception scores predicted treatment response to PRTG. This is the first randomized controlled trial of group-delivered PRT and one of the largest experimental investigations of the PRT model to date. The findings suggest that specific instruction in PRT results in greater skill acquisition for both parents and children, especially in functional and adaptive communication skills. Further research in PRT is warranted to replicate the observed results and address other core ASD symptoms. © 2014 Association for Child and Adolescent Mental Health.

  12. Demand Responsive and Energy Efficient Control Technologies andStrategies in Commercial Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Piette, Mary Ann; Kiliccote, Sila

    2006-09-01

    Commercial buildings account for a large portion of summer peak electric demand. Research results show that there is significant potential to reduce peak demand in commercial buildings through advanced control technologies and strategies. However, a better understanding of commercial buildings contribution to peak demand and the use of energy management and control systems is required to develop this demand response resource to its full potential. The main objectives of the study were: (1) To evaluate the size of contributions of peak demand commercial buildings in the U.S.; (2) To understand how commercial building control systems support energy efficiency and DR; and (3) To disseminate the results to the building owners, facility managers and building controls industry. In order to estimate the commercial buildings contribution to peak demand, two sources of data are used: (1) Commercial Building Energy Consumption Survey (CBECS) and (2) National Energy Modeling System (NEMS). These two sources indicate that commercial buildings noncoincidental peak demand is about 330GW. The project then focused on technologies and strategies that deliver energy efficiency and also target 5-10% of this peak. Based on a building operations perspective, a demand-side management framework with three main features: (1) daily energy efficiency, (2) daily peak load management and (3) dynamic, event-driven DR are outlined. A general description of DR, its benefits, and nationwide DR potential in commercial buildings are presented. Case studies involving these technologies and strategies are described. The findings of this project are shared with building owners, building controls industry, researchers and government entities through a webcast and their input is requested. Their input is presented in the appendix section of this report.

  13. Response to placebo acupuncture in insomnia: a secondary analysis of three randomized controlled trials.

    Science.gov (United States)

    Yeung, Wing-Fai; Chung, Ka-Fai; Yu, Branda Yee-Man; Lao, Lixing

    2015-11-01

    To determine the patient characteristics that are associated with a response to noninvasive placebo acupuncture for insomnia. We performed a secondary analysis of three randomized, double-blind, placebo-controlled trials of acupuncture for primary insomnia and residual insomnia associated with major depression. A total of 86 participants were randomized to receive placebo acupuncture three times per week for three consecutive weeks. Outcome was assessed at 1-week posttreatment. Response was defined as an Insomnia Severity Index (ISI) score improved by eight points or more from baseline to 1-week posttreatment. Sociodemographic, clinical, and baseline characteristics including sleep diary-derived and actigraph-derived sleep parameters as predictors of placebo response were examined using univariate and multivariate logistic regression. The effect size of placebo acupuncture was estimated at 0.18 for total sleep time, 0.08 for sleep efficiency, and 0.92 for ISI score. Eighteen (20.9%) of the 86 participants were responders. Responders had a higher ISI score (p = 0.03), higher sleep diary-derived total sleep time (p = 0.02), less discrepancy between sleep diary-derived and actigraph-derived total sleep time (p = 0.03), and higher expectation toward acupuncture (p = 0.03) at baseline compared to nonresponders. Multivariate regression analysis found that only ISI score remained significant (odds ratio = 1.23, 95% confidence interval = 1.02-1.50, p = 0.03). Baseline sleep parameters and perceived effectiveness were shown to predict the placebo response of acupuncture for insomnia. Although the study was limited by a small sample size, our findings highlighted the potential implication of sleep duration and sleep-state misperception in the treatment of insomnia. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Glycaemic Responses to Corn Meals in Type 2 Diabetics and Non-Diabetic Controls

    Directory of Open Access Journals (Sweden)

    Akinola Dada

    2015-09-01

    Full Text Available Purpose: Dietary modification in association with life style changes is important in the management of the diabetes. Cereals account for as much as 77% of total caloric consumption in most African diets. Corn which is the largest cultivated cereal crop in Nigeria is prepared as a meal in many forms. The objective of this study was to assess the glycaemic responses to different preparations of corn meals. Material and Method: The design was a quasi-experimental with a total of 32 participants, 16 subjects with type diabetes and 16 age-and sex-matched non-diabetic control subjects. After an overnight fast, the participants were given corn meals to eat and had their blood sample collected every 30 minutes for over a 2 hour period for the assessment of blood sugar level and estimation of glycaemic responses. This was repeated weekly till the glycaemic index (GI and plasma sugar level response to the different test corn meal preparation, such as boiled corn, roasted corn, pap and cornflakes had been assessed. Results: All the different corn meal preparations had high GI, with corn flakes having the highest GI and pap the lowest. The GI for the corn meals in the non-diabetic were; pap 71.7±14.4%, roasted corn 76.5±14.9%, boiled corn 82.2±14.9% and cornflakes 88.1±14.4%. Discussion: Methods of preparing a meal from corn affect glycaemic response. Turk Jem 2015; 19: 79-82

  15. Control and regulation of the cellular responses to cold shock: the responses in yeast and mammalian systems

    National Research Council Canada - National Science Library

    Al-Fageeh, Mohamed B; Smales, C Mark

    2006-01-01

    Although the cold-shock response has now been studied in a number of different organisms for several decades, it is only in the last few years that we have begun to understand the molecular mechanisms...

  16. Temperature and pH Responsive Microfibers for Controllable and Variable Ibuprofen Delivery

    Directory of Open Access Journals (Sweden)

    Toan Tran

    2015-01-01

    Full Text Available Electrospun microfibers (MFs composed of pH and temperature responsive polymers can be used for controllable and variable delivery of ibuprofen. First, electrospinning technique was employed to prepare poly(ε-caprolactone (PCL and poly(N-isopropylacrylamide-co-methacrylic acid (pNIPAM-co-MAA MFs containing ibuprofen. It was found that drug release rates from PCL MFs cannot be significantly varied by either temperature (22–40°C or pH values (1.7–7.4. In contrast, the ibuprofen (IP diffusion rates from pNIPAM-co-MAA MFs were very sensitive to changes in both temperature and pH. The IP release from pNIPAM-co-MAA MFs was highly linear and controllable when the temperature was above the lower critical solution temperature (LCST of pNIPAM-co-MAA (33°C and the pH was lower than the pKa of carboxylic acids (pH 2. At room temperature, however, the release rate was dramatically increased by nearly ten times compared to that at higher temperature and lower pH. Such a unique and controllable drug delivery system could be naturally envisioned to find many practical applications in biomedical and pharmaceutical sciences such as programmable transdermal drug delivery.

  17. Neuronal inhibition and excitation, and the dichotomic control of brain hemodynamic and oxygen responses

    DEFF Research Database (Denmark)

    Lauritzen, Martin; Mathiesen, Claus; Schaefer, Katharina

    2012-01-01

    Brain's electrical activity correlates strongly to changes in cerebral blood flow (CBF) and the cerebral metabolic rate of oxygen (CMRO(2)). Subthreshold synaptic processes correlate better than the spike rates of principal neurons to CBF, CMRO(2) and positive BOLD signals. Stimulation-induced ri......Brain's electrical activity correlates strongly to changes in cerebral blood flow (CBF) and the cerebral metabolic rate of oxygen (CMRO(2)). Subthreshold synaptic processes correlate better than the spike rates of principal neurons to CBF, CMRO(2) and positive BOLD signals. Stimulation......-induced rises in CMRO(2) are controlled by the ATP turnover, which depends on the energy used to fuel the Na,K-ATPase to reestablish ionic gradients, while stimulation-induced CBF responses to a large extent are controlled by mechanisms that depend on Ca(2+) rises in neurons and astrocytes. This dichotomy...... and release vasodilators that evoke positive BOLD signals, while the mechanisms that control negative BOLD signals by activity-dependent vasoconstriction are less well understood. Activation of both excitatory and inhibitory neurons produces rises in CBF and positive BOLD signals, while negative BOLD signals...

  18. Altered Innate Immune Responses in Neutrophils from Patients with Well- and Suboptimally Controlled Asthma

    Directory of Open Access Journals (Sweden)

    Francesca S. M. Tang

    2015-01-01

    Full Text Available Background. Respiratory infections are a major cause of asthma exacerbations where neutrophilic inflammation dominates and is associated with steroid refractory asthma. Structural airway cells in asthma differ from nonasthmatics; however it is unknown if neutrophils differ. We investigated neutrophil immune responses in patients who have good (AGood and suboptimal (ASubopt asthma symptom control. Methods. Peripheral blood neutrophils from AGood (ACQ 0.75, n=7, and healthy controls (HC (n=9 were stimulated with bacterial (LPS (1 μg/mL, fMLF (100 nM, and viral (imiquimod (3 μg/mL, R848 (1.5 μg/mL, and poly I:C (10 μg/mL surrogates or live rhinovirus (RV 16 (MOI1. Cell-free supernatant was collected after 1 h for neutrophil elastase (NE and matrix metalloproteinase- (MMP- 9 measurements or after 24 h for CXCL8 release. Results. Constitutive NE was enhanced in AGood neutrophils compared to HC. fMLF stimulated neutrophils from ASubopt but not AGood produced 50% of HC levels. fMLF induced MMP-9 was impaired in ASubopt and AGood compared to HC. fMLF stimulated CXCL8 but not MMP-9 was positively correlated with FEV1 and FEV1/FVC. ASubopt and AGood responded similarly to other stimuli. Conclusions. Circulating neutrophils are different in asthma; however, this is likely to be related to airflow limitation rather than asthma control.

  19. Comparison of Auditory Brainstem Response in Noise Induced Tinnitus and Non-Tinnitus Control Subjects

    Directory of Open Access Journals (Sweden)

    Ghassem Mohammadkhani

    2009-12-01

    Full Text Available Background and Aim: Tinnitus is an unpleasant sound which can cause some behavioral disorders. According to evidence the origin of tinnitus is not only in peripheral but also in central auditory system. So evaluation of central auditory system function is necessary. In this study Auditory brainstem responses (ABR were compared in noise induced tinnitus and non-tinnitus control subjects.Materials and Methods: This cross-sectional, descriptive and analytic study is conducted in 60 cases in two groups including of 30 noise induced tinnitus and 30 non-tinnitus control subjects. ABRs were recorded ipsilateraly and contralateraly and their latencies and amplitudes were analyzed.Results: Mean interpeak latencies of III-V (p= 0.022, I-V (p=0.033 in ipsilatral electrode array and mean absolute latencies of IV (p=0.015 and V (p=0.048 in contralatral electrode array were significantly increased in noise induced tinnitus group relative to control group. Conclusion: It can be concluded from that there are some decrease in neural transmission time in brainstem and there are some sign of involvement of medial nuclei in olivery complex in addition to lateral lemniscus.

  20. Increasing follow-up questionnaire response rates in a randomized controlled trial of telehealth for depression: three embedded controlled studies.

    Science.gov (United States)

    Edwards, Louisa; Salisbury, Chris; Horspool, Kimberley; Foster, Alexis; Garner, Katy; Montgomery, Alan A

    2016-02-24

    Attrition is problematic in trials, and may be exacerbated in longer studies, telehealth trials and participants with depression - three features of The Healthlines Study. Advance notification, including a photograph and using action-oriented email subject lines might increase response rates, but require further investigation. We examined the effectiveness of these interventions in three embedded Healthlines studies. Based in different trial sites, participants with depression were alternately allocated to be pre-called or not ahead of the 8-month follow-up questionnaire (Study 1), randomized to receive a research team photograph or not with their 12-month questionnaire (Study 2), and randomized to receive an action-oriented ('ACTION REQUIRED') or standard ('Questionnaire reminder') 12-month email reminder (Study 3). Participants could complete online or postal questionnaires, and received up to five questionnaire reminders. The primary outcome was completion of the Patient Health Questionnaire (PHQ-9). Secondary outcome measures were the number of reminders and time to questionnaire completion. Of a total of 609 Healthlines depression participants, 190, 251 and 231 participants were included in Studies 1-3 (intervention: 95, 126 and 115), respectively. Outcome completion was ≥90 % across studies, with no differences between trial arms (Study 1: OR 0.38, 95 % CI 0.07-2.10; Study 2: OR 0.84, 95 % CI 0.26-2.66; Study 3: OR 0.53 95 % CI 0.19-1.49). Pre-called participants were less likely to require a reminder (48.4 % vs 62.1 %, OR 0.41, 95 % CI 0.21-0.78), required fewer reminders (adjusted difference in means -0.67, 95 % CI -1.13 to -0.20), and completed follow-up quicker (median 8 vs 15 days, HR 1.35, 95 % CI 1.00-1.82) than control subjects. There were no significant between-group differences in Studies 2 or 3. Eventual response rates in this trial were high, with no further improvement from these interventions. While the photograph and email interventions were

  1. Ovarian response to controlled ovarian hyperstimulation: what does serum FSH say?

    Science.gov (United States)

    Oudshoorn, Simone C; van Tilborg, Theodora C; Hamdine, Ouijdane; Torrance, Helen L; Eijkemans, Marinus J C; Lentjes, Eef G W M; Lambalk, Cornelis B; Broekmans, Frank J M

    2017-08-01

    Do serum FSH levels on day of hCG trigger differ between women with a poor, normal or hyper response to a fixed daily dose of 150 IU recombinant FSH (rFSH)? There is no consistent relationship between ovarian response and serum FSH levels on day of hCG trigger in a 150 IU fixed dose treatment protocol. When ovarian response to stimulation for IVF/ICSI is suboptimal, the FSH dose is often adjusted in a subsequent cycle, thereby assuming that serum FSH levels were inadequate for optimal stimulation. Nested cohort study within a randomized controlled trial conducted at the University Medical Centre Utrecht between March 2009 and July 2011. Blood was drawn from 124 women on cycle Day 2 and on day of hCG triggering. Serum FSH level was determined by the Beckman-Coulter Unicel DXi800 chemiluminescence assay. In order to detect a difference of 2 IU/L between poor, normal and hyper responders, a total of 64 participants (16 poor, 32 normal and 16 hyper responders) would provide 80% power, assuming a standard deviation of 2 and an alpha of 0.05. Women aged ≤39 years with a regular cycle and fixed FSH dose of 150 IU. Exclusion criteria: BMI > 32 kg/m2 and >2 previous unsuccessful IVF/ICSI cycles. The primary outcome measure was serum FSH level on day of triggering. Median [range] body weight was 70.0 kg [55.0-85.6], 68.0 kg [52.0-94] and 60.6 kg [51.0-78.0] for poor (n = 16), normal (n = 94) and hyper (n = 17) responders, respectively. Mean (SD) serum FSH levels on day of triggering were 9.5 IU/L (2.4) in poor, 10.4 IU/L (2.3) in normal and 11.5 IU/L (2.2) in hyper responders. Serum FSH levels on day of hCG in poor responders differed significantly as compared to those in hyper responders (P = 0.03). The number of retrieved oocytes is only minimally determined by serum FSH level on the day of hCG trigger. After correction for age, body weight, basal serum FSH and basal anti-Mullerian hormone the correlation between serum FSH level on the day of hCG and ovarian response

  2. Effects of pressure-controlled and volume-controlled ventilation on respiratory mechanics and systemic stress response during prone position.

    Science.gov (United States)

    Sen, Oznur; Bakan, Mefkur; Umutoglu, Tarik; Aydın, Nurdan; Toptas, Mehmet; Akkoc, Ibrahim

    2016-01-01

    Prone position during general anesthesia for special surgical operations may be related with increased airway pressure, decreased pulmonary and thoracic compliance that may be explained by restriction of chest expansion and compression of abdomen. The optimum ventilation mode for anesthetized patients on prone position was not described and studies comparing volume-controlled ventilation (VCV) and pressure-controlled ventilation (PCV) during prone position are limited. We hypothesized that PCV instead of VCV during prone position could achieve lower airway pressures and reduce the systemic stress response. In this study, we aimed to compare the effects of PCV and VCV modes during prone position on respiratory mechanics, oxygenation, and hemodynamics, as well as blood cortisol and insulin levels, which has not been investigated before. Fifty-four ASA I-II patients, 18-70 years of age, who underwent percutaneous nephrolithotomy on prone position, were randomly selected to receive either the PCV (Group PC, n = 27) or VCV (Group VC, n = 27) under general anesthesia with sevoflurane and fentanyl. Blood sampling was made for baseline arterial blood gases (ABG), cortisol, insulin, and glucose levels. After anesthesia induction and endotracheal intubation, patients in Group PC were given pressure support to form 8 mL/kg tidal volume and patients in Group VC was maintained at 8 mL/kg tidal volume calculated using predicted body weight. All patients were maintained with 5 cmH2O PEEP. Respiratory parameters were recorded during supine and prone position. Assessment of ABG and sampling for cortisol, insulin and glucose levels were repeated during surgery and 60 min after extubation. P-peak and P-plateau levels during supine and prone positions were significantly higher and P-mean and compliance levels during prone position were significantly lower in Group VC when compared with Group PC. Postoperative PaO2 level was significantly higher in Group PC compared with Group

  3. Analytical design and evaluation of an active control system for helicopter vibration reduction and gust response alleviation

    Science.gov (United States)

    Taylor, R. B.; Zwicke, P. E.; Gold, P.; Miao, W.

    1980-01-01

    An analytical study was conducted to define the basic configuration of an active control system for helicopter vibration and gust response alleviation. The study culminated in a control system design which has two separate systems: narrow band loop for vibration reduction and wider band loop for gust response alleviation. The narrow band vibration loop utilizes the standard swashplate control configuration to input controller for the vibration loop is based on adaptive optimal control theory and is designed to adapt to any flight condition including maneuvers and transients. The prime characteristics of the vibration control system is its real time capability. The gust alleviation control system studied consists of optimal sampled data feedback gains together with an optimal one-step-ahead prediction. The prediction permits the estimation of the gust disturbance which can then be used to minimize the gust effects on the helicopter.

  4. Dissociating consciousness from inhibitory control: evidence for unconsciously triggered response inhibition in the stop-signal task

    NARCIS (Netherlands)

    van Gaal, S.; Ridderinkhof, K.R.; van den Wildenberg, W.P.M.; Lamme, V.A.F.

    2009-01-01

    Theories about the functional relevance of consciousness commonly posit that higher order cognitive control functions, such as response inhibition, require consciousness. To test this assertion, the authors designed a masked stop-signal paradigm to examine whether response inhibition could be

  5. Development of an analysis for the determination of coupled helicopter rotor/control system dynamic response. Part 2: Program listing

    Science.gov (United States)

    Sutton, L. R.

    1975-01-01

    A theoretical analysis is developed for a coupled helicopter rotor system to allow determination of the loads and dynamic response behavior of helicopter rotor systems in both steady-state forward flight and maneuvers. The effects of an anisotropically supported swashplate or gyroscope control system and a deformed free wake on the rotor system dynamic response behavior are included.

  6. Are Children with Autism More Responsive to Animated Characters? A Study of Interactions with Humans and Human-Controlled Avatars

    Science.gov (United States)

    Carter, Elizabeth J.; Williams, Diane L.; Hodgins, Jessica K.; Lehman, Jill F.

    2014-01-01

    Few direct comparisons have been made between the responsiveness of children with autism to computer-generated or animated characters and their responsiveness to humans. Twelve 4-to 8-year-old children with autism interacted with a human therapist; a human-controlled, interactive avatar in a theme park; a human actor speaking like the avatar; and…

  7. Physiological Responses to Arm Activity in Individuals With Chronic Obstructive Pulmonary Disease Compared With Healthy Controls: A SYSTEMATIC REVIEW.

    Science.gov (United States)

    Lima, Vanessa Pereira; Iamonti, Vinicius C; Velloso, Marcelo; Janaudis-Ferreira, Tania

    The mechanisms underlying physiological limitations during arm activity in individuals with chronic obstructive pulmonary disease (COPD) are unknown. The objective of this systematic review was to describe cardiorespiratory responses, symptoms, chest wall kinematics, muscle activity, and lung volumes during arm activity in individuals with COPD relative to the responses of healthy controls. Original research articles that compared cardiorespiratory responses, symptoms, muscle activity, chest wall kinematics, and lung function during arm activity between individuals with COPD and healthy controls were identified after searches of 5 electronic databases and reference lists of pertinent articles. Two reviewers performed the electronic and manual searches with 1 screening title and abstracts. Two investigators screened the full texts to determine eligibility for inclusion. One reviewer performed the data extraction and tabulation using a standardized form with a second reviewer double-checking the data extracted. Of the 54 full-text articles assessed for eligibility, 6 met the inclusion criteria. Reduced cardiorespiratory responses during peak arm exercise in individuals with COPD compared with healthy controls were evident. Compared with healthy controls, individuals with COPD had increased dyspnea and hyperinflation during peak arm exercise. Increased effort of the trapezius muscle during arm activities was also found in persons with COPD compared with healthy controls. There is limited evidence describing physiological responses during arm activity in individuals with COPD. Findings of this systematic review suggest that individuals with COPD have decreased cardiorespiratory responses during peak arm exercise compared with controls but increased dyspnea, hyperinflation, and arm muscle effort.

  8. Attitudes and behavioral response toward key tobacco control measures from the FCTC among Chinese urban residents

    Directory of Open Access Journals (Sweden)

    Li Fuzhong

    2007-09-01

    Full Text Available Abstract Background The Chinese National People's Congress ratified the WHO Framework Convention on Tobacco Control (FCTC on 27 August 2005, signaling China's commitment to implement tobacco control policies and legislation consistent with the treaty. This study was designed to examine attitudes towards four WHO FCTC measures among Chinese urban residents. Methods In a cross-sectional design study, survey data were collected from two Chinese urban cities involving a sample of 3,003 residents aged 15 years or older. Through a face-to-face interview, respondents were asked about attitudes toward four tobacco control measures developed by the WHO FCTC. Data on the four dependent measures were analyzed using multivariate logistic regression analyses. Using descriptive statistics, potential change in smoking behavior that smokers might make in response to increasing cigarette prices is also reported. Results 81.8% of the respondents in the study sample supported banning smoking in public places, 68.8% favored increasing the cigarette tax, 85.1% supported health warnings on cigarette packages, and 85.7% favored banning tobacco advertising. The likelihood to support these measures was associated with gender, educational level, and personal income. Smokers were less likely to support these measures than non-smokers, with decreased support expressed by daily smokers compared to occasional smokers, and heavy smokers compared to light smokers. The proportion of switching to cheaper cigarette brands, decreasing smoking, and quitting smoking altogether with increased cigarette prices were 29.1%, 30.90% and 40.0% for occasional smokers, respectively; and 30.8%, 32.7% and 36.5% for daily smokers, respectively. Conclusion Results from this study indicate strong public support in key WHO FCTC measures and that increases in cigarette price may reduce tobacco consumption among Chinese urban residents. Findings from this study have implications with respect to

  9. Mandibular response after rapid maxillary expansion in class II growing patients: a pilot randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Roberta Lione

    2017-11-01

    Full Text Available Abstract Background The aim of this pilot randomized controlled trial (RCT was to evaluate the sagittal mandibular response induced by rapid maxillary expansion (RME therapy in mixed dentition patients with class II malocclusion, comparing the effects of bonded RME and banded RME with a matched untreated class II control group. Methods This RCT was designed in parallel with an allocation ratio of 1:1:1. The sample consisted of 30 children with a mean age of 8.1 ± 0.6 years who were randomly assigned to three groups: group 1 treated with bonded RME, group 2 treated with banded RME, and group 3 the untreated control group. All patients met the following inclusion criteria: early mixed dentition, class II molar relationship, transverse discrepancy ≥ 4 mm, overjet ≥ 5 mm, and prepubertal skeletal maturity stage (CS1–CS2. The expansion screw was activated one quarter of a turn per day (0.25 mm until overcorrection was reached. For each subject, lateral cephalograms and plaster casts were obtained before treatment (T1 and after 1 year (T2. A randomization list was created for the group assignment, with an allocation ratio of 1:1:1. The observer who performed all the measurements was blinded to group assignment. The study was single-blinded in regard to statistical analysis. Results RME was effective in the correction of maxillary deficiency. Class II patients treated with both types of RME showed no significant improvement of the anteroposterior relationship of the maxilla and the mandible at both skeletal and occlusal levels. The acrylic splint RME had significant effects on reducing the skeletal vertical dimension and the gonial angle. Conclusions The orthopedic expansion did not affect the sagittal relationship of class II patients treated in the early mixed dentition when compared with the untreated control group. Additional studies with a larger sample are warranted to elucidate individual variations in dento-skeletal mandibular

  10. Mandibular response after rapid maxillary expansion in class II growing patients: a pilot randomized controlled trial.

    Science.gov (United States)

    Lione, Roberta; Brunelli, Valerio; Franchi, Lorenzo; Pavoni, Chiara; Quiroga Souki, Bernardo; Cozza, Paola

    2017-11-06

    The aim of this pilot randomized controlled trial (RCT) was to evaluate the sagittal mandibular response induced by rapid maxillary expansion (RME) therapy in mixed dentition patients with class II malocclusion, comparing the effects of bonded RME and banded RME with a matched untreated class II control group. This RCT was designed in parallel with an allocation ratio of 1:1:1. The sample consisted of 30 children with a mean age of 8.1 ± 0.6 years who were randomly assigned to three groups: group 1 treated with bonded RME, group 2 treated with banded RME, and group 3 the untreated control group. All patients met the following inclusion criteria: early mixed dentition, class II molar relationship, transverse discrepancy ≥ 4 mm, overjet ≥ 5 mm, and prepubertal skeletal maturity stage (CS1-CS2). The expansion screw was activated one quarter of a turn per day (0.25 mm) until overcorrection was reached. For each subject, lateral cephalograms and plaster casts were obtained before treatment (T1) and after 1 year (T2). A randomization list was created for the group assignment, with an allocation ratio of 1:1:1. The observer who performed all the measurements was blinded to group assignment. The study was single-blinded in regard to statistical analysis. RME was effective in the correction of maxillary deficiency. Class II patients treated with both types of RME showed no significant improvement of the anteroposterior relationship of the maxilla and the mandible at both skeletal and occlusal levels. The acrylic splint RME had significant effects on reducing the skeletal vertical dimension and the gonial angle. The orthopedic expansion did not affect the sagittal relationship of class II patients treated in the early mixed dentition when compared with the untreated control group. Additional studies with a larger sample are warranted to elucidate individual variations in dento-skeletal mandibular response to the maxillary expansion protocol in class

  11. Multifunctional nanoparticle-protein conjugates with controllable bioactivity and pH responsiveness

    Science.gov (United States)

    Liu, Feng; Xue, Lulu; Yuan, Yuqi; Pan, Jingjing; Zhang, Chenjie; Wang, Hongwei; Brash, John L.; Yuan, Lin; Chen, Hong

    2016-02-01

    The modulation of protein activity is of significance for disease therapy, molecular diagnostics, and tissue engineering. Nanoparticles offer a new platform for the preparation of protein conjugates with improved protein properties. In the present work, Escherichia coli (E. coli) inorganic pyrophosphatase (PPase) and poly(methacrylic acid) (PMAA) were attached together to gold nanoparticles (AuNPs), forming AuNP-PPase-PMAA conjugates having controllable multi-biofunctionalities and responsiveness to pH. By treating with poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) and regulating the pH, the bioactivity of the conjugate becomes ``on/off''-switchable. In addition, by taking advantage of the ability of AuNPs to undergo reversible aggregation/dispersion, the conjugates can be recycled and reused multiple times; and due to the shielding effect of the PMAA, the conjugated enzyme has high resistance to protease digestion. This approach has considerable potential in areas such as controlled delivery and release of drugs, biosensing, and biocatalysis.The modulation of protein activity is of significance for disease therapy, molecular diagnostics, and tissue engineering. Nanoparticles offer a new platform for the preparation of protein conjugates with improved protein properties. In the present work, Escherichia coli (E. coli) inorganic pyrophosphatase (PPase) and poly(methacrylic acid) (PMAA) were attached together to gold nanoparticles (AuNPs), forming AuNP-PPase-PMAA conjugates having controllable multi-biofunctionalities and responsiveness to pH. By treating with poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) and regulating the pH, the bioactivity of the conjugate becomes ``on/off''-switchable. In addition, by taking advantage of the ability of AuNPs to undergo reversible aggregation/dispersion, the conjugates can be recycled and reused multiple times; and due to the shielding effect of the PMAA, the conjugated enzyme has high resistance to protease digestion

  12. Spirulina-Templated Metal Microcoils with Controlled Helical Structures for THz Electromagnetic Responses

    Science.gov (United States)

    Kamata, Kaori; Piao, Zhenzi; Suzuki, Soichiro; Fujimori, Takahiro; Tajiri, Wataru; Nagai, Keiji; Iyoda, Tomokazu; Yamada, Atsushi; Hayakawa, Toshiaki; Ishiwara, Mitsuteru; Horaguchi, Satoshi; Belay, Amha; Tanaka, Takuo; Takano, Keisuke; Hangyo, Masanori

    2014-05-01

    Microstructures in nature are ultrafine and ordered in biological roles, which have attracted material scientists. Spirulina forms three-dimensional helical microstructure, one of remarkable features in nature beyond our current processing technology such as lithography in terms of mass-productivity and structural multiplicity. Spirulina varies its diameter, helical pitch, and/or length against growing environment. This unique helix is suggestive of a tiny electromagnetic coil, if composed of electro-conductive metal, which brought us main concept of this work. Here, we describe the biotemplating process onto Spirulina surface to fabricate metal microcoils. Structural parameters of the microcoil can be controlled by the cultivation conditions of Spirulina template and also purely one-handed microcoil can be fabricated. A microcoil dispersion sheet exhibited optically active response attributed to structural resonance in terahertz-wave region.

  13. Controlling the release from enzyme-responsive microcapsules with a smart natural shell.

    Science.gov (United States)

    Ravanfar, Raheleh; Celli, Giovana Bonat; Abbaspourrad, Alireza

    2018-01-22

    We design a natural and simple core-shell structured microcapsule, which releases the cargo only when exposed to lipase. The cargo is entrapped inside a gel matrix, which is surrounded by a double layer shell containing an inner solid lipid layer and an outer polymer layer. This outer polymer layer can be designed according to the intended biological system and is responsible for protecting the microcapsule architecture and transporting the cargo to the desired site of action. The lipid layer contains natural ester bonds, which are digested by lipase and control the release of cargo from the microcapsule core. To demonstrate the feasibility of this approach, our model system includes the colorant bixin entrapped inside a κ-carrageenan gel matrix. This core is surrounded by an inner beeswax-palmitic acid layer and an outer casein-poloxamer 338 layer. These fabricated microcapsules are then applied into Cheddar cheese, where they selectively color the cheese matrix.

  14. Demand Response Control in Low Voltage Grids for Technical and Commercial Aggregation Services

    DEFF Research Database (Denmark)

    Diaz de Cerio Mendaza, Iker; Szczesny, Ireneusz; Pillai, Jayakrishnan Radhakrishna

    2016-01-01

    . In this way, a system operator playing a role of an aggregator not only could trade flexible demand in the power markets but also materialize its energy agreements while ensuring the local network security and reliability. To verify the effectiveness of this extended method, a Danish low voltage networks...... hand, some of those represent a source of flexibility which can be used to satisfy different technical and commercial purposes. This paper introduces an upgraded hierarchical structure which aims to serve as a platform for activating and controlling the demand response in low voltage networks...... is considered. The results show that it is possible to fulfill energy commitments in energy markets such as the regulation power market while respecting the proper network operation. However, the activation of the flexibility offered might be limited depending on the network characteristics and the season...

  15. Pre- and post-flight-test models versus measured skyship-500 control responses

    Science.gov (United States)

    Jex, Henry R.; Magdaleno, Raymond E.; Gelhausen, Paul; Tischler, Mark B.

    1987-01-01

    The dynamical equations-of-motion (EOM) for cruising airships require nonconventional terms to account for buoyancy and apparent-mass-effects, but systematic validation of these equations against flight data is not available. Using a candidate set of EOM, three comparisons are made with carefully-measured describing functions derived from frequency-sweep flight tests on the Skyship-500 airship. The first compares the pre-flight predictions to the data; the second compares the 'best-fit' equations to data at each of two airspeeds and the third compared the ability to extrapolate from one condition to another via airship-specific scaling laws. Two transient responses are also compared. The generally good results demonstrate that fairly simple, perturbation equation models are adequate for many types of flight-control analysis and flying quality evaluations of cruising airships.

  16. A harmonic injection SPWM method for the high-responsive PMSM control system

    Science.gov (United States)

    Lei, Wang; Shuanghui, Hao; Minghui, Hao; Baoyu, Song

    2016-01-01

    In a permanent magnet synchronous motor (PMSM) control system, usually, the phase voltage instruction is limited independently to prevent a three-phase pulse width modulation (PWM) wave from overflowing. This method decreases the efficiency of the bus voltage and causes voltage vector direction errors. To solve these problems, we propose a harmonic injection sinusoidal pulse-width modulation (SPWM). This method uses harmonic injected sinusoidal PWM to improve the utilisation ratio of the bus voltage, and consequently improve system performance. In this paper, we analyse the problem in terms of potential difference. The simulation results show that the proposed method can increase the utilisation ratio of the bus voltage up to 15.4%, and the voltage vector mode obtained with the proposed algorithm is larger than that obtained with the conventional one. The method with harmonic injection consequently improves current response, without affecting voltage vector accuracy. The experiment results validate the proposed method.

  17. Heat Pump Water Heaters: Controlled Field Research of Impact on Space Conditioning and Demand Response Characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Parker, Graham B.; Widder, Sarah H.; Eklund, Ken; Petersen, Joseph M.; Sullivan, Greg

    2015-10-05

    A new generation of heat pump water heaters (HPWH) has been introduced into the U.S. market that promises to provide significant energy savings for water heating. Many electric utilities are promoting their widespread adoption as a key technology for meeting energy conservation goals and reducing greenhouse gas emissions. There is, however, considerable uncertainty regarding the space conditioning impact of an HPWH installed in a conditioned space. There is also uncertainty regarding the potential for deployment of HPWHs in demand response (DR) programs to help manage and balance peak utility loads in a similar manner as conventional electric resistance water heaters (ERWH). To help answer these uncertainties, controlled experiments have been undertaken over 30 months in a matched pair of unoccupied Lab Homes located on the campus of the Pacific Northwest National Laboratory (PNNL) in Richland, Washington.

  18. iNKT cell cytotoxic responses control T-lymphoma growth in vitro and in vivo

    Science.gov (United States)

    Bassiri, Hamid; Das, Rupali; Guan, Peng; Barrett, David M.; Brennan, Patrick J.; Banerjee, Pinaki P.; Wiener, Susan J.; Orange, Jordan S.; Brenner, Michael B.; Grupp, Stephan A.; Nichols, Kim E.

    2013-01-01

    Invariant natural killer T (iNKT) cells comprise a lineage of CD1d-restricted glycolipid-reactive T lymphocytes with important roles in host immunity to cancer. iNKT cells indirectly participate in antitumor responses by inducing dendritic cell maturation and producing cytokines that promote tumor clearance by CD8+ T and NK cells. Although iNKT cells thereby act as potent cellular adjuvants, it is less clear whether they directly control the growth of tumors. To gain insights into the direct contribution of iNKT cells to tumor immune surveillance, we developed in vitro and in vivo systems to selectively examine the antitumor activity of iNKT cells in the absence of other cytolytic effectors. Using the EL4 T-lymphoma cell line as a model, we find that iNKT cells exert robust and specific lysis of tumor cells in vitro in a manner that is differentially-induced by iNKT cell agonists of varying TCR affinities, such as OCH, α-galactosyl ceramide and PBS44. In vitro blockade of CD1d-mediated lipid antigen presentation, disruption of T cell receptor (TCR) signaling, or loss of perforin expression significantly reduce iNKT cell killing. Consistent with these findings, iNKT cell reconstitution of T, B, and NK cell-deficient mice slows EL4 growth in vivo via TCR-CD1d and perforin-dependent mechanisms. Together, these observations establish that iNKT cells are sufficient to control the growth of T-lymphoma in vitro and in vivo. They also suggest that the induction of iNKT cell cytotoxic responses in situ might serve as a more effective strategy to prevent and/or treat CD1d+ cancers, such as T-lymphoma. PMID:24563871

  19. The Developmental Intestinal Regulator ELT-2 Controls p38-Dependent Immune Responses in Adult C. elegans.

    Science.gov (United States)

    Block, Dena H S; Twumasi-Boateng, Kwame; Kang, Hae Sung; Carlisle, Jolie A; Hanganu, Alexandru; Lai, Ty Yu-Jen; Shapira, Michael

    2015-05-01

    GATA transcription factors play critical roles in cellular differentiation and development. However, their roles in mature tissues are less understood. In C. elegans larvae, the transcription factor ELT-2 regulates terminal differentiation of the intestine. It is also expressed in the adult intestine, where it was suggested to maintain intestinal structure and function, and where it was additionally shown to contribute to infection resistance. To study the function of elt-2 in adults we characterized elt-2-dependent gene expression following its knock-down specifically in adults. Microarray analysis identified two ELT-2-regulated gene subsets: one, enriched for hydrolytic enzymes, pointed at regulation of constitutive digestive functions as a dominant role of adult elt-2; the second was enriched for immune genes that are induced in response to Pseudomonas aeruginosa infection. Focusing on the latter, we used genetic analyses coupled to survival assays and quantitative RT-PCR to interrogate the mechanism(s) through which elt-2 contributes to immunity. We show that elt-2 controls p38-dependent gene induction, cooperating with two p38-activated transcription factors, ATF-7 and SKN-1. This demonstrates a mechanism through which the constitutively nuclear elt-2 can impact induced responses, and play a dominant role in C. elegans immunity.

  20. Response of different lines and cultivars of rice subjected to low temperatures under controlled conditions

    Directory of Open Access Journals (Sweden)

    Sandra H Díaz Solís

    2017-01-01

    Full Text Available Rice (Oryza sativa L. is the most important food crop in the world and primary source of food for more than a third of the population. The low temperatures are among the main abiotic stresses that affect the yield of this cereal. The objective of this work was to determinate the response of different lines and cultivars of rice in seedling state to low temperature stress under controlled conditions. 172 lines and cultivars were studied. It were subjected to 5 0C for 24 hours, when the plants were about three to four leaves. The evaluations were conducted by measured of chlorophyll fluorescence and visually. A wide range of response was obtained, which indicated a high allelic diversity for the low temperatures sensitivity in the studied germplasm. A group of 30 cultivars responded more favorably to the cold and the most prominent cultivars showed Fv/Fm values between 0.80 and 0.89. A significant relationship between visual evaluation and chlorophyll fluorescence was found. The correlation coefficient revealed a moderately strong relationship between both variables. Tolerant plant materials were more consistently identified. However, the dispersion between methods increased to more susceptible cultivars.   Keywords: cold tolerance, chlorophyll fluorescence, Oryza sativa, visual evaluation

  1. Foliar Potassium Fertilizer Additives Affect Soybean Response and Weed Control with Glyphosate

    Directory of Open Access Journals (Sweden)

    Kelly A. Nelson

    2012-01-01

    Full Text Available Research in 2004 and 2005 determined the effects of foliar-applied K-fertilizer sources (0-0-62-0 (%N-%P2O5-%K2O-%S, 0-0-25-17, 3-18-18-0, and 5-0-20-13 and additive rates (2.2, 8.8, and 17.6 kg K ha−1 on glyphosate-resistant soybean response and weed control. Field experiments were conducted at Novelty and Portageville with high soil test K and weed populations and at Malden with low soil test K and weed populations. At Novelty, grain yield increased with fertilizer additives at 8.8 kg K ha−1 in a high-yield, weed-free environment in 2004, but fertilizer additives reduced yield up to 470 kg ha−1 in a low-yield year (2005 depending on the K source and rate. At Portageville, K-fertilizer additives increased grain yield from 700 to 1160 kg ha−1 compared to diammonium sulfate, depending on the K source and rate. At Malden, there was no yield response to K sources. Differences in leaf tissue K (P=0.03, S (P=0.03, B (P=0.0001, and Cu (P=0.008 concentrations among treatments were detected 14 d after treatment at Novelty and Malden. Tank mixtures of K-fertilizer additives with glyphosate may provide an option for foliar K applications.

  2. Athletic background is related to superior trunk proprioceptive ability, postural control, and neuromuscular responses to sudden perturbations.

    Science.gov (United States)

    Glofcheskie, Grace O; Brown, Stephen H M

    2017-04-01

    Trunk motor control is essential for athletic performance, and inadequate trunk motor control has been linked to an increased risk of developing low back and lower limb injury in athletes. Research is limited in comparing relationships between trunk neuromuscular control, postural control, and trunk proprioception in athletes from different sporting backgrounds. To test for these relationships, collegiate level long distance runners and golfers, along with non-athletic controls were recruited. Trunk postural control was investigated using a seated balance task. Neuromuscular control in response to sudden trunk loading perturbations was measured using electromyography and kinematics. Proprioceptive ability was examined using active trunk repositioning tasks. Both athlete groups demonstrated greater trunk postural control (less centre of pressure movement) during the seated task compared to controls. Athletes further demonstrated faster trunk muscle activation onsets, higher muscle activation amplitudes, and less lumbar spine angular displacement in response to sudden trunk loading perturbations when compared to controls. Golfers demonstrated less absolute error and variable error in trunk repositioning tasks compared to both runners and controls, suggestive of greater proprioceptive ability. This suggests an interactive relationship between neuromuscular control, postural control, and proprioception in athletes, and that differences exist between athletes of various training backgrounds. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. 45 CFR 2508.9 - What officials are responsible for the security, management and control of Corporation record...

    Science.gov (United States)

    2010-10-01

    ..., management and control of Corporation record keeping systems? 2508.9 Section 2508.9 Public Welfare... IMPLEMENTATION OF THE PRIVACY ACT OF 1974 § 2508.9 What officials are responsible for the security, management and control of Corporation record keeping systems? (a) The Director of Administration and Management...

  4. Provision of secondary frequency control via demand response activation on thermostatically controlled loads: Solutions and experiences from Denmark

    DEFF Research Database (Denmark)

    Lakshmanan, Venkatachalam; Marinelli, Mattia; Hu, Junjie

    2016-01-01

    loads, they represent a suitable alternative to conventional sources for providing such control. An experimental investigation with domestic fridges representing the TCLs was conducted in an islanded power system to evaluate the secondary frequency control. The investigation quantifies the flexibility...

  5. Field Testing of Telemetry for Demand Response Control of Small Loads

    Energy Technology Data Exchange (ETDEWEB)

    Lanzisera, Steven [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Weber, Adam [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Liao, Anna [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Schetrit, Oren [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Kiliccote, Sila [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Piette, Mary Ann [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2018-01-30

    The electricity system in California, from generation through loads, must be prepared for high renewable penetration and increased electrification of end uses while providing increased resilience and lower operating cost. California has an aggressive renewable portfolio standard that is complemented by world-leading greenhouse gas goals. The goal of this project was to evaluate methods of enabling fast demand response (DR) signaling to small loads for low-cost site enablement. We used OpenADR 2.0 to meet telemetry requirements for providing ancillary services, and we used a variety of low-cost devices coupled with open-source software to enable an end-to-end fast DR. The devices, architecture, implementation, and testing of the system is discussed in this report. We demonstrate that the emerging Internet of Things (IoT) and Smart Home movements provide an opportunity for diverse small loads to provide fast, low-cost demand response. We used Internet-connected lights, thermostats, load interruption devices, and water heaters to demonstrate an ecosystem of controllable devices. The system demonstrated is capable of providing fast load shed for between 20 dollars and $300 per kilowatt (kW) of available load. The wide range results from some loads may have very low cost but also very little shed capability (a 10 watt [W] LED light can only shed a maximum of 10 W) while some loads (e.g., water heaters or air conditioners) can shed several kilowatts but have a higher initial cost. These costs, however, compare well with other fast demand response costs, with typically are over $100/kilowatt of shed. We contend these loads are even more attractive than their price suggests because many of them will be installed for energy efficiency or non-energy benefits (e.g., improved lighting quality or controllability), and the ability to use them for fast DR is a secondary benefit. Therefore the cost of enabling them for DR may approach zero if a software-only solution can be

  6. The Importance of the Nurse Cells and Regulatory Cells in the Control of T Lymphocyte Responses

    Directory of Open Access Journals (Sweden)

    María Guadalupe Reyes García

    2013-01-01

    Full Text Available T lymphocytes from the immune system are bone marrow-derived cells whose development and activities are carefully supervised by two sets of accessory cells. In the thymus, the immature young T lymphocytes are engulfed by epithelial “nurse cells” and retained in vacuoles, where most of them (95% are negatively selected and removed when they have an incomplete development or express high affinity autoreactive receptors. The mature T lymphocytes that survive to this selection process leave the thymus and are controlled in the periphery by another subpopulation of accessory cells called “regulatory cells,” which reduce any excessive immune response and the risk of collateral injuries to healthy tissues. By different times and procedures, nurse cells and regulatory cells control both the development and the functions of T lymphocyte subpopulations. Disorders in the T lymphocytes development and migration have been observed in some parasitic diseases, which disrupt the thymic microenvironment of nurse cells. In other cases, parasites stimulate rather than depress the functions of regulatory T cells decreasing T-mediated host damages. This paper is a short review regarding some features of these accessory cells and their main interactions with T immature and mature lymphocytes. The modulatory role that neurotransmitters and hormones play in these interactions is also revised.

  7. Foxp3+ follicular regulatory T cells control T follicular helper cells and the germinal center response

    Science.gov (United States)

    Linterman, Michelle A.; Pierson, Wim; Lee, Sau K.; Kallies, Axel; Kawamoto, Shimpei; Rayner, Tim F.; Srivastava, Monika; Divekar, Devina P.; Beaton, Laura; Hogan, Jennifer J.; Fagarasan, Sidonia; Liston, Adrian; Smith, Kenneth G. C.; Vinuesa, Carola G.

    2011-01-01

    Follicular helper (TFH) cells provide crucial signals to germinal center B cells undergoing somatic hypermutation and selection that results in affinity maturation. Tight control of TFH numbers maintains self-tolerance. We describe a population of Foxp3+Blimp-1+CD4+ T cells constituting 10-25% of the CXCR5highPD-1highCD4+ T cells found in germinal center after immunization. These follicular regulatory T cells (TFR) share phenotypic characteristics with TFH and conventional Foxp3+ regulatory T cells (Treg) yet are distinct from either. Similar to TFH cells, TFR development depends on Bcl-6, SAP, CD28 and B cells; however TFR originate from thymic-derived Foxp3+ precursors, not naïve or TFH cells. TFR are suppressive in vitro and limit TFH and germinal center B cell numbers in vivo. In the absence of TFR, an outgrowth of non-antigen-specific B cells in germinal centers leads to fewer antigen-specific cells. Thus, Treg cells use the TFH differentiation pathway to produce specialized suppressor cells that control the germinal center response. PMID:21785433

  8. Temperature control of molecular circuit switch responsible for virulent phenotype expression in uropathogenic Escherichia coli

    Science.gov (United States)

    Samoilov, Michael

    2010-03-01

    The behavior and fate of biological organisms are to a large extent dictated by their environment, which can be often viewed as a collection of features and constraints governed by physics laws. Since biological systems comprise networks of molecular interactions, one such key physical property is temperature, whose variations directly affect the rates of biochemical reactions involved. For instance, temperature is known to control many gene regulatory circuits responsible for pathogenicity in bacteria. One such example is type 1 fimbriae (T1F) -- the foremost virulence factor in uropathogenic E. coli (UPEC), which accounts for 80-90% of all community-acquired urinary tract infections (UTIs). The expression of T1F is randomly `phase variable', i.e. individual cells switch between virulent/fimbriate and avirulent/afimbriate phenotypes, with rates regulated by temperature. Our computational investigation of this process, which is based on FimB/FimE recombinase-mediated inversion of fimS DNA element, offers new insights into its discrete-stochastic kinetics. In particular, it elucidates the logic of T1F control optimization to the host temperature and contributes further understanding toward the development of novel therapeutic approaches to UPEC-caused UTIs.

  9. [Acupuncture in fibromyalgia: a randomized, controlled study addressing the immediate pain response].

    Science.gov (United States)

    Stival, Rebecca Saray Marchesini; Cavalheiro, Patrícia Rechetello; Stasiak, Camila Edith Stachera; Galdino, Dayana Talita; Hoekstra, Bianca Eliza; Schafranski, Marcelo Derbli

    2014-01-01

    To evaluate the efficacy of acupuncture in the treatment of fibromyalgia, considering the immediate response of the visual analogue pain scale (VAS) as its primary outcome. Randomized, controlled, double-blind study including 36 patients with fibromyalgia (ACR 1990) selected from the outpatient rheumatology clinic, Santa Casa de Misericórdia, Ponta Grossa, PR. Twenty-one patients underwent an acupuncture session, under the principles of the traditional Chinese medicine, and 15 patients underwent a placebo procedure (sham acupuncture). For pain assessment, the subjects completed a Visual Analogue Scale (VAS) before and immediately after the proposed procedure. The mean change in VAS was compared among groups. The variation between the final and initial VAS values was -4.36±3.23 (P=0.0001) in the treatment group and -1.70±1.55 in the control group (P=0.06). The difference in terms of amplitude of variation of VAS (initial - final VAS) among groups favored the actual procedure (P=0.005). The effect size (ES) for the treatment group was d=1.7, which is considered a large effect. Although small, the statistical power of the sample for these results was very relevant (94.8%). Acupuncture has proven effective in the immediate pain reduction in patients with fibromyalgia, with a quite significant effect size. Copyright © 2014 Elsevier Editora Ltda. All rights reserved.

  10. Teaching Parents About Responsive Feeding Through a Vicarious Learning Video: A Pilot Randomized Controlled Trial.

    Science.gov (United States)

    Ledoux, Tracey; Robinson, Jessica; Baranowski, Tom; O'Connor, Daniel P

    2017-06-01

    The American Academy of Pediatrics and World Health Organization recommend responsive feeding (RF) to promote healthy eating behaviors in early childhood. This project developed and tested a vicarious learning video to teach parents RF practices. A RF vicarious learning video was developed using community-based participatory research methods. Fifty parents of preschoolers were randomly assigned to watch Happier Meals or a control video about education. Knowledge and beliefs about RF practices were measured 1 week before and immediately after intervention. Experimental group participants also completed measures of narrative engagement and video acceptability. Seventy-four percent of the sample was White, 90% had at least a college degree, 96% were married, and 88% made >$50,000/year. RF knowledge increased ( p = .03) and positive beliefs about some unresponsive feeding practices decreased ( ps < .05) more among experimental than control parents. Knowledge and belief changes were associated with video engagement ( ps < .05). Parents perceived Happier Meals as highly relevant, applicable, and informative. Community-based participatory research methods were instrumental in developing this vicarious learning video, with preliminary evidence of effectiveness in teaching parents about RF. Happier Meals is freely available for parents or community health workers to use when working with families to promote healthy eating behaviors in early childhood.

  11. DeSUMOylation Controls Insulin Exocytosis in Response to Metabolic Signals

    Directory of Open Access Journals (Sweden)

    Patrick E. MacDonald

    2012-05-01

    Full Text Available The secretion of insulin by pancreatic islet β-cells plays a pivotal role in glucose homeostasis and diabetes. Recent work suggests an important role for SUMOylation in the control of insulin secretion from β-cells. In this paper we discuss mechanisms whereby (deSUMOylation may control insulin release by modulating β-cell function at one or more key points; and particularly through the acute and reversible regulation of the exocytotic machinery. Furthermore, we postulate that the SUMO-specific protease SENP1 is an important mediator of insulin exocytosis in response to NADPH, a metabolic secretory signal and major determinant of β-cell redox state. Dialysis of mouse β-cells with NADPH efficiently amplifies β-cell exocytosis even when extracellular glucose is low; an effect that is lost upon knockdown of SENP1. Conversely, over-expression of SENP1 itself augments β-cell exocytosis in a redox-dependent manner. Taken together, we suggest that (deSUMOylation represents an important mechanism that acutely regulates insulin secretion and that SENP1 can act as an amplifier of insulin exocytosis.

  12. Defining genes using "blueprint" versus "instruction" metaphors: effects for genetic determinism, response efficacy, and perceived control.

    Science.gov (United States)

    Parrott, Roxanne; Smith, Rachel A

    2014-01-01

    Evidence supports mixed attributions aligned with personal and/or clinical control and gene expression for health in this era of genomic science and health care. We consider variance in these attributions and possible relationships to individual mind sets associated with essentialist beliefs that genes determine health versus threat beliefs that genes increase susceptibility for disease and severity linked to gene-environment interactions. Further, we contribute to theory and empirical research to evaluate the use of metaphors to define genes. Participants (N = 324) read a message that varied the introduction by providing a definition of genes that used either an "instruction" metaphor or a "blueprint" metaphor. The "instruction" metaphor compared to the "blueprint" metaphor promoted stronger threat perceptions, which aligned with both belief in the response efficacy of genetic research for health and perceived behavioral control linked to genes and health. The "blueprint" metaphor compared to the "instruction" metaphor promoted stronger essentialist beliefs, which aligned with more intense positive regard for the efficacy of genetic research and human health. Implications for health communicators include societal effects aligned with stigma and discrimination that such findings portend.

  13. A short receptor downregulates JAK/STAT signalling to control the Drosophila cellular immune response.

    Directory of Open Access Journals (Sweden)

    Rami Makki

    2010-08-01

    Full Text Available The posterior signalling centre (PSC, a small group of specialised cells, controls hemocyte (blood cell homeostasis in the Drosophila larval hematopoietic organ, the lymph gland. This role of the PSC is very reminiscent of the "niche," the micro-environment of hematopoietic stem cells in vertebrates. We have recently shown that the PSC acts in a non-cell-autonomous manner to maintain janus tyrosine kinase/signal transducers and activators of transcription (JAK/STAT signalling in hematopoietic progenitors (prohemocytes, thereby preserving the multipotent character necessary for their differentiation into lamellocytes, a cryptic and dedicated immune cell type required to fight specific immune threats such as wasp parasitism. In this report, on the basis of a knock out generated by homologous recombination, we show that a short type I cytokine-related receptor CG14225/Latran is required for switching off JAK/STAT signalling in prohemocytes. This is a prerequisite to massive differentiation of lamellocytes upon wasp parasitisation. In vivo and cell culture assays indicate that Latran forms heteromers with Domeless, the Drosophila type I cytokine signalling receptor related to mammalian GP130, and antagonises Domeless activity in a dose-dependent manner. Our analysis further shows that a primary immune response to wasp parasitism is a strong decrease in cytokine mRNA levels in the lymph gland, followed by an increase in the latran/domeless ratio. We propose that this sequence of events culminates in the complete inhibition of residual JAK/STAT signalling by Latran. JAK/STAT activity has been associated with several human diseases including leukaemia while knock-out studies in mice point to a central role of this pathway in hematopoiesis and regulation of immune functions. The specific function of Drosophila Latran is, to our knowledge, the first in vivo example of a role for a nonsignalling receptor in controlling a dedicated immune response, and

  14. Event-related potentials in response to emotional words in patients with major depressive disorder and healthy controls.

    Science.gov (United States)

    Liu, Hong; Yin, Hui-fang; Wu, Da-xing; Xu, Shu-jing

    2014-01-01

    Dysfunctional cognitive processing and abnormal brain activation in response to emotional stimuli have long been recognized as core features of the major depressive disorder (MDD). The aim of this study was to examine how Chinese patients with MDD process Chinese emotional words presented to either the left (LH) or right hemisphere (RH). Reaction time (RT) and the late positive component of the event-related potential were measured while subjects judged the valence (positive or negative) of emotional words written in Chinese. Compared to healthy controls, patients with MDD exhibited slower RTs in response to negative words. In all subjects, the RTs in response to negative words were significantly faster than RTs in response to positive words presented to the LH, as well as significantly faster than responses to negative words presented to the RH. Compared to healthy controls, MDD patients exhibited reduced activation of the central and left regions of the brain in response to both negative and positive words. In healthy controls, the posterior brain areas were more active than the anterior brain areas when responding to negative words. All individuals showed faster RTs in response to negative words compared to positive words. In addition, MDD patients showed lateralization of brain activity in response to emotional words, whereas healthy individuals did not show this lateralization. Posterior brain areas appear to play an especially important role in discriminating and experiencing negative emotional words. This study provides further evidence in support of the negative bias hypothesis and the emotional processing theory.

  15. Drought Response in Wheat: Key Genes and Regulatory Mechanisms Controlling Root System Architecture and Transpiration Efficiency

    Directory of Open Access Journals (Sweden)

    Manoj Kulkarni

    2017-12-01

    Full Text Available Abiotic stresses such as, drought, heat, salinity, and flooding threaten global food security. Crop genetic improvement with increased resilience to abiotic stresses is a critical component of crop breeding strategies. Wheat is an important cereal crop and a staple food source globally. Enhanced drought tolerance in wheat is critical for sustainable food production and global food security. Recent advances in drought tolerance research have uncovered many key genes and transcription regulators governing morpho-physiological traits. Genes controlling root architecture and stomatal development play an important role in soil moisture extraction and its retention, and therefore have been targets of molecular breeding strategies for improving drought tolerance. In this systematic review, we have summarized evidence of beneficial contributions of root and stomatal traits to plant adaptation to drought stress. Specifically, we discuss a few key genes such as, DRO1 in rice and ERECTA in Arabidopsis and rice that were identified to be the enhancers of drought tolerance via regulation of root traits and transpiration efficiency. Additionally, we highlight several transcription factor families, such as, ERF (ethylene response factors, DREB (dehydration responsive element binding, ZFP (zinc finger proteins, WRKY, and MYB that were identified to be both positive and negative regulators of drought responses in wheat, rice, maize, and/or Arabidopsis. The overall aim of this review is to provide an overview of candidate genes that have been identified as regulators of drought response in plants. The lack of a reference genome sequence for wheat and non-transgenic approaches for manipulation of gene functions in wheat in the past had impeded high-resolution interrogation of functional elements, including genes and QTLs, and their application in cultivar improvement. The recent developments in wheat genomics and reverse genetics, including the availability of a

  16. Electrically responsive microreservoires for controllable delivery of dexamethasone in bone tissue engineering

    Science.gov (United States)

    Paun, Irina Alexandra; Zamfirescu, Marian; Luculescu, Catalin Romeo; Acasandrei, Adriana Maria; Mustaciosu, Cosmin Catalin; Mihailescu, Mona; Dinescu, Maria

    2017-01-01

    A major concern in orthopedic implants is to decrease the chronic inflammation using specific drug therapies. The newest strategies rely on the controlled delivery of antiinflammatory drugs from carrier biointerfaces designed in the shape of 3D architectures. We report on electrically responsive microreservoires (ERRs) acting as microcontainers for antiinflammatory drugs, as potential biointerfaces in orthopedic implants. The ERRs consist in arrays of vertical microtubes produced by laser direct writing using two photon polymerization effects (2PP_LDW) of a commercially available photoresist, IP-L780. A polypyrrole (conductive)/dexamethasone (drug model) (PPy/Dex) mixture was loaded into the ERRs via a simple immersion process. Then, the ERRs were sealed with a poly(lactic-co-glycolic acid)(PLGA) layer by Matrix Assisted Pulsed Laser Evaporation. ERRs stimulation using voltage cycles between -1 V and +1 V, applied at specific time intervals, at a scan rate of 0.1 V s-1, enabled to control the Dex release. The release time scales were between 150 and 275 h, while the concentrations of Dex released were between 450-460 nM after three applied voltage cycles, for different microreservoires dimensions. The proposed approach was validated in osteoblast-like MG-63 cell cultures. Cell viability and adhesion assays showed that the Dex-loaded ERRs sustained the cells growth and preserved their characteristic polygonal shape. Importantly, for the electrically-stimulated Dex release, the level of the alkaline phosphatase activity increased twice, the osteogenic differentiation surpassed by 1.6 times and the relative level of osteocalcin gene expression was 2.2 times higher as compared with the unstimulated drug release. Overall, the ERRs were able to accelerate the cells osteogenic differentiation via electrically controlled release of Dex.

  17. Gastrointestinal nematode infection and performance of weaned stocker calves in response to anthelmintic control strategies.

    Science.gov (United States)

    Walker, R S; Miller, J E; Monlezun, C J; LaMay, D; Navarre, C; Ensley, D

    2013-10-18

    Gastrointestinal nematode (GIN) parasite control recommendations are in a state of flux because of the increase in anthelmintic resistant cattle parasites, such as Cooperia spp. In addition, Cooperia spp. infection is typically high in warm-season grass pastures and can affect growth performance of grazing stocker calves in the Gulf Coast Region. This study evaluated the effects of moxidectin pour-on, oxfendazole oral suspension, or a combination of the two given at separate times on infection and performance of weaned beef calves grazing summer forages. Steers (n=42) and heifers (n=31) were stratified by sex, d-11 fecal egg count (FEC), and d-1 shrunk body weight (BW) to one of 10 pastures with four anthelmintic treatments and one control. Treatments included: (1) oxfendazole given on d 0 and moxidectin on d 73 (O+M), (2) moxidectin given on d 0 and oxfendazole on d 73 (M+O), (3) moxidectin given on d 0 (M), (4) oxfendazole given on d 0 (O) and (5) no anthelmintic given (CON). Calves grazed for d-110 beginning May 27th. Response variables were FEC (collected on d-11, 14, 31, 45, 59, 73, 87 and 108), coprocultures (evaluated for d 87 and 108), final shrunk BW, shrunk BW gain, average daily gain (ADG), and full BW gain (collected on d 31, 59, 73, 87, and 108). Calves treated with either oxfendazole (O+M and O) or moxidectin (M+O and M) on d 0 had significantly lower (PCooperia spp. and Ostertagia spp. On d 87, no larvae were recovered from the M+O treated calves, whereas the O+M treated calves had 94% Cooperia spp. and 3% Ostertagia spp. recovered. Providing a benzimidazole with a macrocyclic lactone given at two different periods may provide better GIN parasite control and improve animal gains for stocker calves grazing warm-season grass pastures. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Tissue response of selective retina therapy by means of a feedback-controlled energy ramping mode.

    Science.gov (United States)

    Park, Young-Gun; Seifert, Eric; Roh, Young J; Theisen-Kunde, Dirk; Kang, Seungbum; Brinkmann, Ralf

    2014-12-01

    The purpose of the study was to evaluate the safety and selectivity of the retinal pigment epithelium lesions by using automatic energy ramping and dosimetry technique for selective retina therapy and to investigate the healing response. Ten eyes of Chinchilla Bastard rabbits were treated with an automatic dosage controlled selective retina therapy laser (frequency doubled Q-switched Nd:YLF, wavelength: 527 nm, pulse duration: 1.7 μs, repetition rate: 100 Hz, pulse energy: linear increasing from pulse to pulse up to shut down - maximal 110 μJ, max. number of pulses in a burst: 30, retinal spot diameter: 133 μm). After treatment, fundus photography, optical coherence tomography and fluorescein angiography were performed at three time points from 1 h to 3 weeks. Histological analysis was performed. A total of 381 selective retina therapy laser spots were tested (range 13-104 μJ).Typical fundus photographs obtained at 1 h after irradiation showed that 379 out of 381 lesions produced by selective retina therapy were not visible ophthalmoscopically and the lesions could be detected by angiography only. Optical coherence tomography images revealed that the structure of photoreceptors was preserved, but a disrupted retinal pigment epithelium layer was observed as was expected. By 3 weeks, histology showed selective retinal pigment epithelium damage without any effect on the inner retina and focal proliferation of the retinal pigment epithelium layer. Automatically controlled selective retina therapy is a significant improvement in this innovative treatment. It could be demonstrated that the non-contact, reflectometric technique with a controlled pulse energy ramp is safe and selective. © 2014 Royal Australian and New Zealand College of Ophthalmologists.

  19. Resting Vagal Tone and Vagal Response to Stress: Associations with Anxiety, Aggression and Perceived Anxiety Control among Youth

    OpenAIRE

    Scott, Brandon G.; Weems, Carl F.

    2014-01-01

    This study tested the associations of both resting vagal tone and vagal response to stress with anxiety control beliefs, anxiety, and aggression among 80 youth (aged 11-17 years). Measures included physiological assessments of emotion regulation along with youth self-report of anxiety control beliefs, anxiety, and aggression and caregiver reports of their child's anxiety and aggression. Resting vagal tone was positively related to anxiety control beliefs, but negatively associated with anxiet...

  20. A gene expression profile of the myocardial response to clenbuterol.

    Science.gov (United States)

    Lara-Pezzi, Enrique; Terracciano, Cesare M N; Soppa, Gopal K R; Smolenski, Ryszard T; Felkin, Leanne E; Yacoub, Magdi H; Barton, Paul J R

    2009-06-01

    Clenbuterol is currently being used as part of a clinical trial into a novel therapeutic approach for the treatment of end-stage heart failure. The purpose of this study was to determine the global pattern of myocardial gene expression in response to clenbuterol and to identify novel targets and pathways involved. Rats were treated with clenbuterol (n = 6) or saline (n = 6) for periods of 1, 3, 9, or 28 days. Rats treated for 28 days were also subject to continuous electrocardiogram analysis using implantable telemetry. RNA was extracted from rats at days 1 and 28 and used from microarray analysis, and further samples from rats at days 1, 3, 9, and 28 were used for analysis by real-time polymerase chain reaction. Clenbuterol treatment induced rapid development of cardiac hypertrophy with increased muscle mass at day 1 and elevated heart rate and QT interval throughout the 28-day period. Microarray analysis revealed a marked but largely transitory change in gene expression with 1,423 genes up-regulated and 964 genes down-regulated at day 1. Up-regulated genes revealed an unexpected association with angiogenesis and integrin-mediated cell adhesion and signaling. Moreover, direct treatment of endothelial cells cultured in vitro resulted in increased cell proliferation and tube formation. Our data show that clenbuterol treatment is associated with rapid cardiac hypertrophy and identify angiogenesis and integrin signaling as novel pathways of clenbuterol action. The data have implications both for our understanding of the physiologic hypertrophy induced by clenbuterol and for treatment of heart failure.

  1. A double-blind, placebo-controlled evaluation of the erectile response to transurethral alprostadil.

    Science.gov (United States)

    Hellstrom, W J; Bennett, A H; Gesundheit, N; Kaiser, F E; Lue, T F; Padma-Nathan, H; Peterson, C A; Tam, P Y; Todd, L K; Varady, J C; Place, V A

    1996-12-01

    Previous studies have indicated that the urethra may provide an effective route for administering vasoactive medication for the treatment of erectile dysfunction. We evaluated the safety and efficacy of alprostadil administered intraurethrally at home for the treatment of this disorder. This prospective, multicenter, double-blind, placebo-controlled study evaluated the erectile response to randomly assigned doses of transurethral alprostadil at home in 68 men with long-standing (mean 41 months) erectile dysfunction of primarily organic etiology. Patients completing the study each administered a random sequence of four different doses (125, 250, 500, and 1000 micrograms) and placebo over a 2 to 4-week period. Assessments included the couples' ability to have intercourse, patient ratings of erectile response by both categorical and visual analogue scales, penile volume measurements, and overall assessments of comfort and ease of administration. Overall, 75.4% (49 of 65) of study patients achieved full enlargement of the penis and 49.2% (32 of 65) achieved an erection judged by the patient to be sufficient for intercourse. In addition, 63.6% (42 of 66) of patients reported intercourse. Efficacy was similar across etiologies. The most common side effect was penile pain, which occurred in association with 9.1% to 18.3% of alprostadil administrations, depending on dose. Mean comfort ratings ranged from 79 to 87, depending on dose, where 0 = severe discomfort and 100 = comfortable; ease of administration scores were above 90 for each dose, where 0 = difficult and 100 = easy. There were no episodes of priapism in this study. Short-term treatment with transurethral alprostadil produced erections resulting in sexual intercourse in most patients with chronic erectile dysfunction. This therapy may be a useful treatment option for patients with erectile dysfunction.

  2. Adolescent standing postural response to backpack loads: a randomised controlled experimental study

    Directory of Open Access Journals (Sweden)

    Pirunsan Ubon

    2002-04-01

    Full Text Available Abstract Background Backpack loads produce changes in standing posture when compared with unloaded posture. Although 'poor' unloaded standing posture has been related to spinal pain, there is little evidence of whether, and how much, exposure to posterior load produces injurious effects on spinal tissue. The objective of this study was to describe the effect on adolescent sagittal plane standing posture of different loads and positions of a common design of school backpack. The underlying study aim was to test the appropriateness of two adult 'rules-of-thumb'-that for postural efficiency, backpacks should be worn high on the spine, and loads should be limited to 10% of body weight. Method A randomised controlled experimental study was conducted on 250 adolescents (12–18 years, randomly selected from five South Australian metropolitan high schools. Sagittal view anatomical points were marked on head, neck, shoulder, hip, thigh, knee and ankle. There were nine experimental conditions: combinations of backpack loads (3, 5 or 10% of body weight and positions (backpack centred at T7, T12 or L3. Sagittal plane photographs were taken of unloaded standing posture (baseline, and standing posture under the experimental conditions. Posture was quantified from the x (horizontal coordinate of each anatomical point under each experimental condition. Differences in postural response were described, and differences between conditions were determined using Analysis of Variance models. Results Neither age nor gender was a significant factor when comparing postural response to backpack loads or conditions. Backpacks positioned at T7 produced the largest forward (horizontal displacement at all the anatomical points. The horizontal position of all anatomical points increased linearly with load. Conclusion There is evidence refuting the 'rule-of-thumb' to carry the backpack high on the back. Typical school backpacks should be positioned with the centre at waist or

  3. Dynamic m6A mRNA methylation directs translational control of heat shock response

    Science.gov (United States)

    Zhou, Jun; Wan, Ji; Gao, Xiangwei; Zhang, Xingqian; Qian, Shu-Bing

    2015-01-01

    The most abundant mRNA post-transcriptional modification is N6-methyladenosine (m6A) that has broad roles in RNA biology1-5. In mammalian cells, the asymmetric distribution of m6A along mRNAs leaves relatively less methylation in the 5′ untranslated region (5′UTR) compared to other regions6,7. However, whether and how 5′UTR methylation is regulated is poorly understood. Despite the crucial role of the 5′UTR in translation initiation, very little is known whether m6A modification influences mRNA translation. Here we show that in response to heat shock stress, m6A is preferentially deposited to the 5′UTR of newly transcribed mRNAs. We found that the dynamic 5′UTR methylation is a result of stress-induced nuclear localization of YTHDF2, a well characterized m6A “reader”. Upon heat shock stress, the nuclear YTHDF2 preserves 5′UTR methylation of stress-induced transcripts by limiting the m6A “eraser” FTO from demethylation. Remarkably, the increased 5′UTR methylation in the form of m6A promotes cap-independent translation initiation, providing a mechanism for selective mRNA translation under heat shock stress. Using Hsp70 mRNA as an example, we demonstrate that a single site m6A modification in the 5′UTR enables translation initiation independent of the 5′ end m7G cap. The elucidation of the dynamic feature of 5′UTR methylation and its critical role in cap-independent translation not only expands the breadth of physiological roles of m6A, but also uncovers a previously unappreciated translational control mechanism in heat shock response. PMID:26458103

  4. Controlling

    OpenAIRE

    Tůmová, Jana

    2009-01-01

    The diploma thesis focuses on the problems of operational controllership and the instruments used for their solution. In connection with these issues the thesis also defines the role of the controller, in particular his authorities and responsibilities. The theoretical part of the work looks at the academic conception of controlleship. The practical part describes the main functions, duties, activities and the system of cooperation in between controllership and other departments in particular...

  5. The caspase-8/RIPK3 signaling axis in antigen presenting cells controls the inflammatory arthritic response.

    Science.gov (United States)

    Dominguez, Salina; Montgomery, Anna B; Haines, G Kenneth; Bloomfield, Christina L; Cuda, Carla M

    2017-10-04

    to arthritis to revert back to control levels via a mechanism potentially independent of cell death. Mixed bone marrow chimeric mice demonstrate that caspase-8 deficiency does not confer preferential expansion of synovial macrophage and dendritic cell populations, nor do caspase-8-deficient synovial populations succumb to RIPK3-mediated necroptotic death. These data demonstrate that caspase-8 functions in synovial antigen-presenting cells to regulate the response to inflammatory stimuli by controlling RIPK3 action, and this delicate balance maintains homeostasis within the joint.

  6. Genes controlling vaccine responses and disease resistance to respiratory viral pathogens in cattle.

    Science.gov (United States)

    Glass, Elizabeth J; Baxter, Rebecca; Leach, Richard J; Jann, Oliver C

    2012-07-15

    Farm animals remain at risk of endemic, exotic and newly emerging viruses. Vaccination is often promoted as the best possible solution, and yet for many pathogens, either there are no appropriate vaccines or those that are available are far from ideal. A complementary approach to disease control may be to identify genes and chromosomal regions that underlie genetic variation in disease resistance and response to vaccination. However, identification of the causal polymorphisms is not straightforward as it generally requires large numbers of animals with linked phenotypes and genotypes. Investigation of genes underlying complex traits such as resistance or response to viral pathogens requires several genetic approaches including candidate genes deduced from knowledge about the cellular pathways leading to protection or pathology, or unbiased whole genome scans using markers spread across the genome. Evidence for host genetic variation exists for a number of viral diseases in cattle including bovine respiratory disease and anecdotally, foot and mouth disease virus (FMDV). We immunised and vaccinated a cattle cross herd with a 40-mer peptide derived from FMDV and a vaccine against bovine respiratory syncytial virus (BRSV). Genetic variation has been quantified. A candidate gene approach has grouped high and low antibody and T cell responders by common motifs in the peptide binding pockets of the bovine major histocompatibility complex (BoLA) DRB3 gene. This suggests that vaccines with a minimal number of epitopes that are recognised by most cattle could be designed. Whole genome scans using microsatellite and single nucleotide polymorphism (SNP) markers has revealed many novel quantitative trait loci (QTL) and SNP markers controlling both humoral and cell-mediated immunity, some of which are in genes of known immunological relevance including the toll-like receptors (TLRs). The sequencing, assembly and annotation of livestock genomes and is continuing apace. In

  7. A Feed-Forward Control Realizing Fast Response for Three-Branch Interleaved DC-DC Converter in DC Microgrid

    DEFF Research Database (Denmark)

    Wang, Haojie; Han, Minxiao; Yan, Wenli

    2016-01-01

    changing. A prototype of the TIDC is developed and an experimental platform is built. The experiment results show that DC bus voltage sags or swells caused by load changing can be reduced and the time for voltage recovery can be decreased significantly with the proposed feed-forward control.......It is a common practice for storage batteries to be connected to DC microgrid buses through DC-DC converters for voltage support on islanded operation mode. A feed-forward control based dual-loop constant voltage PI control for three-branch interleaved DC-DC converters (TIDC) is proposed...... for storage batteries in DC microgrids. The working principle of TIDC is analyzed, and the factors influencing the response rate based on the dual-loop constant voltage control for TIDC are discussed, and then the method of feed-forward control for TIDC is studied to improve the response rate for load...

  8. Analysis of Control Policies and Dynamic Response of a Q-Car 2-DOF Semi Active System

    Directory of Open Access Journals (Sweden)

    S.I. Ihsan

    2008-01-01

    Full Text Available Several control policies of Q-car 2-DOF semiactive system, namely skyhook, groundhook and hybrid controls are presented. Their ride comfort, suspension displacement and road-holding performances are analyzed and compared with passive system. The analysis covers both transient and steady state responses in time domain and transmissibility response in frequency domain. The results show that the hybrid control policy yields better comfort than a passive suspension, without reducing the road-holding quality or increasing the suspension displacement for typical passenger cars. The hybrid control policy is also shown to be a better compromise between comfort, road-holding and suspension displacement than the skyhook and groundhook control policies.

  9. A Feed-Forward Control Realizing Fast Response for Three-Branch Interleaved DC-DC Converter in DC Microgrid

    Directory of Open Access Journals (Sweden)

    Haojie Wang

    2016-07-01

    Full Text Available It is a common practice for storage batteries to be connected to DC microgrid buses through DC-DC converters for voltage support on islanded operation mode. A feed-forward control based dual-loop constant voltage PI control for three-branch interleaved DC-DC converters (TIDC is proposed for storage batteries in DC microgrids. The working principle of TIDC is analyzed, and the factors influencing the response rate based on the dual-loop constant voltage control for TIDC are discussed, and then the method of feed-forward control for TIDC is studied to improve the response rate for load changing. A prototype of the TIDC is developed and an experimental platform is built. The experiment results show that DC bus voltage sags or swells caused by load changing can be reduced and the time for voltage recovery can be decreased significantly with the proposed feed-forward control.

  10. Measurement and control of bias in patient reported outcomes using multidimensional item response theory.

    Science.gov (United States)

    Dowling, N Maritza; Bolt, Daniel M; Deng, Sien; Li, Chenxi

    2016-05-26

    Patient-reported outcome (PRO) measures play a key role in the advancement of patient-centered care research. The accuracy of inferences, relevance of predictions, and the true nature of the associations made with PRO data depend on the validity of these measures. Errors inherent to self-report measures can seriously bias the estimation of constructs assessed by the scale. A well-documented disadvantage of self-report measures is their sensitivity to response style (RS) effects such as the respondent's tendency to select the extremes of a rating scale. Although the biasing effect of extreme responding on constructs measured by self-reported tools has been widely acknowledged and studied across disciplines, little attention has been given to the development and systematic application of methodologies to assess and control for this effect in PRO measures. We review the methodological approaches that have been proposed to study extreme RS effects (ERS). We applied a multidimensional item response theory model to simultaneously estimate and correct for the impact of ERS on trait estimation in a PRO instrument. Model estimates were used to study the biasing effects of ERS on sum scores for individuals with the same amount of the targeted trait but different levels of ERS. We evaluated the effect of joint estimation of multiple scales and ERS on trait estimates and demonstrated the biasing effects of ERS on these trait estimates when used as explanatory variables. A four-dimensional model accounting for ERS bias provided a better fit to the response data. Increasing levels of ERS showed bias in total scores as a function of trait estimates. The effect of ERS was greater when the pattern of extreme responding was the same across multiple scales modeled jointly. The estimated item category intercepts provided evidence of content independent category selection. Uncorrected trait estimates used as explanatory variables in prediction models showed downward bias. A

  11. A nucleotide metabolite controls stress-responsive gene expression and plant development.

    Directory of Open Access Journals (Sweden)

    Hao Chen

    Full Text Available Abiotic stress, such as drought and high salinity, activates a network of signaling cascades that lead to the expression of many stress-responsive genes in plants. The Arabidopsis FIERY1 (FRY1 protein is a negative regulator of stress and abscisic acid (ABA signaling and exhibits both an inositol polyphosphatase and a 3',5'-bisphosphate nucleotidase activity in vitro. The FRY1 nucleotidase degrades the sulfation byproduct 3'-phosphoadenosine-5'-phosphate (PAP, yet its in vivo functions and particularly its roles in stress gene regulation remain unclear. Here we developed a LC-MS/MS method to quantitatively measure PAP levels in plants and investigated the roles of this nucleotidase activity in stress response and plant development. It was found that PAP level was tightly controlled in plants and did not accumulate to any significant level either under normal conditions or under NaCl, LiCl, cold, or ABA treatments. In contrast, high levels of PAP were detected in multiple mutant alleles of FRY1 but not in mutants of other FRY1 family members, indicating that FRY1 is the major enzyme that hydrolyzes PAP in vivo. By genetically reducing PAP levels in fry1 mutants either through overexpression of a yeast PAP nucleotidase or by generating a triple mutant of fry1 apk1 apk2 that is defective in the biosynthesis of the PAP precursor 3'-phosphoadenosine-5'-phosphosulfate (PAPS, we demonstrated that the developmental defects and superinduction of stress-responsive genes in fry1 mutants correlate with PAP accumulation in planta. We also found that the hypersensitive stress gene regulation in fry1 requires ABH1 but not ABI1, two other negative regulators in ABA signaling pathways. Unlike in yeast, however, FRY1 overexpression in Arabidopsis could not enhance salt tolerance. Taken together, our results demonstrate that PAP is critical for stress gene regulation and plant development, yet the FRY1 nucleotidase that catabolizes PAP may not be an in vivo salt

  12. Robust tactile sensory responses in finger area of primate motor cortex relevant to prosthetic control

    Science.gov (United States)

    Schroeder, Karen E.; Irwin, Zachary T.; Bullard, Autumn J.; Thompson, David E.; Bentley, J. Nicole; Stacey, William C.; Patil, Parag G.; Chestek, Cynthia A.

    2017-08-01

    Objective. Challenges in improving the performance of dexterous upper-limb brain-machine interfaces (BMIs) have prompted renewed interest in quantifying the amount and type of sensory information naturally encoded in the primary motor cortex (M1). Previous single unit studies in monkeys showed M1 is responsive to tactile stimulation, as well as passive and active movement of the limbs. However, recent work in this area has focused primarily on proprioception. Here we examined instead how tactile somatosensation of the hand and fingers is represented in M1. Approach. We recorded multi- and single units and thresholded neural activity from macaque M1 while gently brushing individual finger pads at 2 Hz. We also recorded broadband neural activity from electrocorticogram (ECoG) grids placed on human motor cortex, while applying the same tactile stimulus. Main results. Units displaying significant differences in firing rates between individual fingers (p  <  0.05) represented up to 76.7% of sorted multiunits across four monkeys. After normalizing by the number of channels with significant motor finger responses, the percentage of electrodes with significant tactile responses was 74.9%  ±  24.7%. No somatotopic organization of finger preference was obvious across cortex, but many units exhibited cosine-like tuning across multiple digits. Sufficient sensory information was present in M1 to correctly decode stimulus position from multiunit activity above chance levels in all monkeys, and also from ECoG gamma power in two human subjects. Significance. These results provide some explanation for difficulties experienced by motor decoders in clinical trials of cortically controlled prosthetic hands, as well as the general problem of disentangling motor and sensory signals in primate motor cortex during dextrous tasks. Additionally, examination of unit tuning during tactile and proprioceptive inputs indicates cells are often tuned differently in different

  13. A nucleotide metabolite controls stress-responsive gene expression and plant development

    KAUST Repository

    Chen, Hao

    2011-10-19

    Abiotic stress, such as drought and high salinity, activates a network of signaling cascades that lead to the expression of many stress-responsive genes in plants. The Arabidopsis FIERY1 (FRY1) protein is a negative regulator of stress and abscisic acid (ABA) signaling and exhibits both an inositol polyphosphatase and a 3?,5?-bisphosphate nucleotidase activity in vitro. The FRY1 nucleotidase degrades the sulfation byproduct 3?-phosphoadenosine-5?-phosphate (PAP), yet its in vivo functions and particularly its roles in stress gene regulation remain unclear. Here we developed a LC-MS/MS method to quantitatively measure PAP levels in plants and investigated the roles of this nucleotidase activity in stress response and plant development. It was found that PAP level was tightly controlled in plants and did not accumulate to any significant level either under normal conditions or under NaCl, LiCl, cold, or ABA treatments. In contrast, high levels of PAP were detected in multiple mutant alleles of FRY1 but not in mutants of other FRY1 family members, indicating that FRY1 is the major enzyme that hydrolyzes PAP in vivo. By genetically reducing PAP levels in fry1 mutants either through overexpression of a yeast PAP nucleotidase or by generating a triple mutant of fry1 apk1 apk2 that is defective in the biosynthesis of the PAP precursor 3?-phosphoadenosine-5?-phosphosulfate (PAPS), we demonstrated that the developmental defects and superinduction of stress-responsive genes in fry1 mutants correlate with PAP accumulation in planta. We also found that the hypersensitive stress gene regulation in fry1 requires ABH1 but not ABI1, two other negative regulators in ABA signaling pathways. Unlike in yeast, however, FRY1 overexpression in Arabidopsis could not enhance salt tolerance. Taken together, our results demonstrate that PAP is critical for stress gene regulation and plant development, yet the FRY1 nucleotidase that catabolizes PAP may not be an in vivo salt toxicity target

  14. Radiotherapy in desmoid tumors. Treatment response, local control, and analysis of local failures

    Energy Technology Data Exchange (ETDEWEB)

    Santti, Kirsi; Beule, Annette; Tuomikoski, Laura; Jaeaeskelaeinen, Anna-Stina; Saarilahti, Kauko; Tarkkanen, Maija; Blomqvist, Carl [Helsinki University Hospital and University of Helsinki, Comprehensive Cancer Center, Helsinki (Finland); Roenty, Mikko [HUSLAB and University of Helsinki, Department of Pathology, Helsinki (Finland); Ihalainen, Hanna [Helsinki University Hospital and University of Helsinki, Department of Plastic Surgery, Helsinki (Finland)

    2017-04-15

    Desmoid tumors (aggressive fibromatosis) are rare soft tissue tumors which frequently recur after surgery. Desmoid tumors arise from musculoaponeurotic tissue in the extremities, head and neck, abdominal wall, or intra-abdominally. Our aim was to examine the outcome of radiotherapy of desmoid tumors in a single institution series. We evaluated 41 patients with desmoid tumors treated with 49 radiotherapies between 1987 and 2012. Radiologic images for response evaluation were reassessed and responses to treatment registered according to RECIST criteria 1.1. For patients with local failures radiation dose distribution was determined in each local failure volume using image co-registration. Recurrences were classified as in-target, marginal, or out-of-target. Prognostic factors for radiotherapy treatment failure were evaluated. Radiotherapy doses varied from 20-63 Gy (median 50 Gy) with a median fraction size of 2 Gy. The objective response rate to definitive radiotherapy was 55% (12/22 patients). Median time to response was 14 months. A statistically significant dose-response relation for definitive and postoperative radiotherapy was observed both in univariate (p-value 0.002) and in multivariate analysis (p-value 0.02) adjusted for potential confounding factors. Surgery before radiotherapy or surgical margin had no significant effect on time to progression. Nine of 11 (82%) local failures were classified as marginal and two of 11 (18%) in-target. None of the recurrences occurred totally out-of-target. Radiotherapy is a valuable option for treating desmoid tumors. Radiotherapy dose appears to be significantly associated to local control. (orig.) [German] Desmoide (aggressive Fibromatosen) sind seltene Weichteiltumore der muskulaeren Membranen von Kopf, Hals, Extremitaeten und Bauchwand. Ziel war es, die Wirksamkeit der Strahlentherapie bei aggressiver Fibromatose an einer einzelnen Klinik zu untersuchen. Ausgewertet wurden 41 Patienten mit aggressiver Fibromatose, die

  15. Acute physiological response to indoor cycling with and without hydration; case and self-control study.

    Science.gov (United States)

    Ramos-Jiménez, A; Hernández-Torres, R P; Wall-Medrano, A; Torres-Durán, P V; Juárez-Oropeza, M A; Solis Ceballos, J A

    2013-01-01

    Oral rehydration drinks help maintain physical capacity and hydration during exercise. Evaluate, in a case and self-control study, the effectiveness of three hydration and exercise protocols on work capacity and physical and psychosomatic stress during indoor cycling (InC). 14 middle-aged eutrophic men participated in three controlled randomly and not sequentially hydration (~278 mL 6/c 15 min) and exercise (InC/90 min) protocols: No liquids, plain water, or sports drinks (SD). The response variables were: Body temperature (BT), heart rate (HR), and mean blood pressure (MBP). The covariables: Distance traveled (DT), ergometer resistance (R), body fat (BF), difference in body weight between tests (rBW), and age of the participants. The differences between protocols were evaluated using GLM Repeated Measures, the independence of associations by multiple linear regression. In non-liquids, the subjects showed higher BT, HR, and MBP than when they drank plain water or SD (p hydration protocols. BT was the most sensitive variable detected by the hydration status of the subjects. 34%, 99%, and 21% of the associated variance to HR, MBP, and BT was explained by DT + BT, BT + BF, and ΔBW + age + R + DT + BF, respectively. Liquid intake with or without electrolytes does not affect work capacity, and they are equally effective as hydration sources during =?90 min of InC at strong and very strong intensities. Body temperature is the most sensitive variable detected by the subject's hydration status during exercise. Copyright © AULA MEDICA EDICIONES 2013. Published by AULA MEDICA. All rights reserved.

  16. Emotional responses to images of food in adults with an eating disorder: a comparative study with healthy and clinical controls.

    Science.gov (United States)

    Hay, Phillipa; Katsikitis, Mary

    2014-08-01

    Emotive responses to foods in people with eating disorders are incompletely understood in relation to whether the extent of emotional response is due to the eating disorder or non-specific emotional states. The aims of the present study were to investigate negative and positive emotive responses to food images in adults with an eating disorder, and to compare responses to a (i) healthy and a (ii) clinic (psychiatry) control group. Participants viewed 20 images (16 of foods previously found to evoke fear, disgust and happiness and 4 neutral images) at half-minute intervals and rated emotive responses on 3 visual analogue scales for each image. Participants with an eating disorder (n=26) were found to have significantly increased negative emotive (disgust and fear) responses and reduced positive (happiness) responses to the images compared to the 20 clinic and 61 healthy participants. Differences between groups remained significant when controlling for baseline levels of fear, disgust and happiness. Thus, the emotive responses to foods did not appear due to non-specific increases in anxiety or depression but rather was due to the presence of an eating disorder. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Endoplasmic reticulum proteins quality control and the unfolded protein response: the regulative mechanism of organisms against stress injuries.

    Science.gov (United States)

    Fu, Xi Ling; Gao, Dong Sheng

    2014-01-01

    The endoplasmic reticulum is the cellular compartment in which secretory proteins are synthesized and folded. Perturbations of endoplasmic reticulum homeostasis lead to the accumulation of unfolded proteins. The activation of the unfolded protein response during endoplasmic reticulum stress transmits information about the status of protein folding to the cytosol and nucleus. The unfolded protein response leads to the upregulation of genes encoding endoplasmic reticulum chaperones, attenuation of translation, and initiation of the endoplasmic reticulum quality control system to restore endoplasmic reticulum homeostasis. When the unfolded protein response is insufficient to rebuild the steady state in endoplasmic reticulum, the programmed cell death or apoptosis would be initiated, by triggering cell injuries, even to cell death through apoptosis signals. In this review, we briefly outline research on the chaperones and foldases conserved in eukaryotes and plants, and describe the general principles and mechanisms of the endoplasmic reticulum quality control and the unfolded protein response. We describe the current models for the molecular mechanism of the unfolded protein response in plants, and emphasize the role of inositol requiring enzyme-1-dependent network in the unfolded protein response. Finally, we give a general overview of the directions for future research on the unfolded protein response in plants and its role in the response to environmental stresses. © 2014 International Union of Biochemistry and Molecular Biology.

  18. Induction of Gag-Specific CD4 T Cell Responses during Acute HIV Infection Is Associated with Improved Viral Control

    Science.gov (United States)

    Schieffer, Miriam; Jessen, Heiko K.; Oster, Alexander F.; Pissani, Franco; Soghoian, Damien Z.; Lu, Richard; Jessen, Arne B.; Zedlack, Carmen; Schultz, Bruce T.; Davis, Isaiah; Ranasinghe, Srinika; Rosenberg, Eric S.; Alter, Galit; Schumann, Ralf R.

    2014-01-01

    ABSTRACT Effector CD4 T cell responses have been shown to be critically involved in the containment and clearance of viral pathogens. However, their involvement in the pathogenesis of HIV infection is less clear, given their additional role as preferred viral targets. We previously demonstrated that the presence of HIV-specific CD4 T cell responses is somewhat associated with HIV control and that specific CD4 T cell functions, such as direct cytolytic activity, can contribute to control of HIV viremia. However, little is known about how the induction of HIV-specific CD4 T cell responses during acute HIV infection influences disease progression and whether responses induced during the early phase of infection are preferentially depleted. We therefore longitudinally assessed, in a cohort of 55 acutely HIV-infected individuals, HIV-specific CD4 T cell responses from acute to chronic infection. Interestingly, we found that the breadth, magnitude, and protein dominance of HIV-specific CD4 T cell responses remained remarkably stable over time. Moreover, we found that the epitopes targeted at a high frequency in acute HIV infection were recognized at the same frequency by HIV-specific CD4 T cells in chronic HIV infection. Interestingly the induction of Gag-specific CD4 T cell responses in acute HIV infection was significantly inversely correlated with viral set point in chronic HIV infection (R = −0.5; P = 0.03), while the cumulative contribution of Env-specific CD4 T cell responses showed the reverse effect. Moreover, individuals with HIV-specific CD4 T cell responses dominantly targeting Gag over Env in acute HIV infection remained off antiretroviral therapy significantly longer (P = 0.03; log rank). Thus, our data suggest that the induction of HIV-specific CD4 T cell responses during acute HIV infection is beneficial overall and does not fuel disease progression. IMPORTANCE CD4 T cells are critical for the clearance and control of viral infections. However, HIV

  19. A Simple Autonomous Current-Sharing Control Strategy for Fast Dynamic Response of Parallel Inverters in Islanded Microgrids

    DEFF Research Database (Denmark)

    Guan, Yajuan; Vasquez, Juan Carlos; Guerrero, Josep M.

    2014-01-01

    This paper proposed a novel control strategy based on a virtual resistance and a phase locked loop for parallel three-phase inverters. The proposed controller can overcome the drawbacks of the conventional droop control such as slow transient response, complex design, and limited stability margins....... The load sharing capability can be also obtained under asymmetrical output impedances in which the conventional droop controller was not properly working. The proposed approach has been verified by means of simulations and experimental results in a laboratory-scale prototype....

  20. N-terminal pro-atrial natriuretic peptide response to acute exercise in depressed patients and healthy controls

    DEFF Research Database (Denmark)

    Krogh, Jesper; Ströhle, Andreas; Westrin, Asa

    2011-01-01

    BACKGROUND: The dysfunction of hypothalamic-pituitary-adrenal (HPA) axis in major depression includes hyperactivity and reduced feedback inhibition. Atrial natriuretic peptide (ANP) is able to reduce the HPA-axis response to stress and has an anxiolytic effect in rodents and humans. We hypothesized...... that patients with depression would have an attenuated N-terminal proANP (NT-proANP) response to acute exercise compared to healthy controls. Secondly, we aimed to assess the effect of antidepressants on NT-proANP response to acute exercise. METHODS: We examined 132 outpatients with mild to moderate depression...... (ICD-10) and 44 healthy controls, group matched for age, sex, and BMI. We used an incremental bicycle ergometer test as a physical stressor. Blood samples were drawn at rest, at exhaustion, and 15, 30, and 60min post-exercise. RESULTS: The NT-proANP response to physical exercise differed between...

  1. N-terminal pro-atrial natriuretic peptide response to acute exercise in depressed patients and healthy controls

    DEFF Research Database (Denmark)

    Krogh, Jesper; Ströhle, Andreas; Westrin, Asa

    2011-01-01

    that patients with depression would have an attenuated N-terminal proANP (NT-proANP) response to acute exercise compared to healthy controls. Secondly, we aimed to assess the effect of antidepressants on NT-proANP response to acute exercise. METHODS: We examined 132 outpatients with mild to moderate depression...... (ICD-10) and 44 healthy controls, group matched for age, sex, and BMI. We used an incremental bicycle ergometer test as a physical stressor. Blood samples were drawn at rest, at exhaustion, and 15, 30, and 60min post-exercise. RESULTS: The NT-proANP response to physical exercise differed between......BACKGROUND: The dysfunction of hypothalamic-pituitary-adrenal (HPA) axis in major depression includes hyperactivity and reduced feedback inhibition. Atrial natriuretic peptide (ANP) is able to reduce the HPA-axis response to stress and has an anxiolytic effect in rodents and humans. We hypothesized...

  2. Theory of Solvation-Controlled Reactions in Stimuli-Responsive Nanoreactors

    CERN Document Server

    Angioletti-Uberti, Stefano; Ballauff, Matthias; Dzubiella, Joachim

    2015-01-01

    Metallic nanoparticles embedded in stimuli-responsive polymers can be regarded as nanoreactors since their catalytic activity can be changed within wide limits: the physicochemical properties of the polymer network can be tuned and switched by external parameters, e.g. temperature or pH, and thus allows a selective control of reactant mobility and concentration close to the reaction site. Based on a combination of Debye's model of diffusion through an energy landscape and a two-state model for the polymer, here we develop an analytical expression for the observed reaction rate constant $k_{\\rm obs}$. Our formula shows an exponential dependence of this rate on the solvation free enthalpy change $\\Delta \\bar{G}_{\\rm sol}$, a quantity which describes the partitioning of the reactant in the network versus bulk. Thus, changes in $\\Delta \\bar{G}_{\\rm sol}$, and not in the diffusion coefficient, will be the decisive factor affecting the reaction rate in most cases. A comparison with recent experimental data on switc...

  3. Multiobjective Optimal Control of Longitudinal Seismic Response of a Multitower Cable-Stayed Bridge

    Directory of Open Access Journals (Sweden)

    Geng Fangfang

    2016-01-01

    Full Text Available The dynamic behavior of a multitower cable-stayed bridge with the application of partially longitudinal constraint system using viscous fluid dampers under real earthquake ground motions is presented. The study is based on the dynamic finite element model of the Jiashao Bridge, a six-tower cable-stayed bridge in China. The prime aim of the study is to investigate the effectiveness of viscous fluid dampers on the longitudinal seismic responses of the bridge and put forth a multiobjective optimization design method to determine the optimized parameters of the viscous fluid dampers. The results of the investigations show that the control objective of the multitower cable-stayed bridge with the partially longitudinal constraint system is to yield maximum reductions in the base forces of bridge towers longitudinally restricted with the bridge deck, with slight increases in the base forces of bridge towers longitudinally unrestricted with the bridge deck. To this end, a multiobjective optimization design method that uses a nondominating sort genetic algorithm II (NSGA-II is used to optimize parameters of the viscous fluid dampers. The effectiveness of the proposed optimization design method is demonstrated for the multitower cable-stayed bridge with the partially longitudinal constraint system, which reveals that a design engineer can choose a set of proper parameters of the viscous fluid dampers from Pareto optimal fronts that can satisfy the desired performance requirements.

  4. T-cell cytokines differentially control human monocyte antimicrobial responses by regulating vitamin D metabolism.

    Science.gov (United States)

    Edfeldt, Kristina; Liu, Philip T; Chun, Rene; Fabri, Mario; Schenk, Mirjam; Wheelwright, Matthew; Keegan, Caroline; Krutzik, Stephan R; Adams, John S; Hewison, Martin; Modlin, Robert L

    2010-12-28

    We investigated the mechanisms by which T-cell cytokines are able to influence the Toll-like receptor (TLR)-induced, vitamin D-dependent antimicrobial pathway in human monocytes. T-cell cytokines differentially influenced TLR2/1-induced expression of the antimicrobial peptides cathelicidin and DEFB4, being up-regulated by IFN-γ, down-regulated by IL-4, and unaffected by IL-17. The Th1 cytokine IFN-γ up-regulated TLR2/1 induction of 25-hydroxyvitamin D-1α-hydroxylase (i.e., CYP27B1), leading to enhanced bioconversion of 25-hydroxyvitamin D(3) (25D(3)) to its active metabolite 1,25D(3). In contrast, the Th2 cytokine IL-4, by itself and in combination with the TLR2/1 ligand, induced catabolism of 25D(3) to the inactive metabolite 24,25D(3), and was dependent on expression of vitamin D-24-hydroxylase (i.e., CYP24A1). Therefore, the ability of T-cell cytokines to differentially control monocyte vitamin D metabolism represents a mechanism by which cell-mediated immune responses can regulate innate immune mechanisms to defend against microbial pathogens.

  5. Performance of Remotely Controlled Mandibular Protrusion Sleep Studies for Prediction of Oral Appliance Treatment Response.

    Science.gov (United States)

    Sutherland, Kate; Ngiam, Joachim; Cistulli, Peter A

    2017-03-15

    Mandibular protrusion during sleep monitoring has been proposed as a method to predict oral appliance treatment outcome. A commercial remotely controlled mandibular protrusion (RCMP) device has become available for this purpose with predictive accuracy demonstrated in an initial study. Our aim was to validate this RCMP method for oral appliance treatment outcome prediction in a clinical sleep laboratory setting. Forty-two obstructive sleep apnea (OSA) patients (apnea-hypopnea index [AHI] > 10 events/h) were recruited to undergo a RCMP sleep study before commencing oral appliance treatment. The RCMP study was used to make a prediction of treatment "Success" or "Failure" based on a rule of ≤ 1 respiratory event per 5 min supine rapid eye movement sleep. Oral appliance treatment response was verified by polysomonography and defined as treatment AHI 30 events/h). Two participants (5%) were not able to tolerate the RCMP study. Oral appliance treatment outcome was verified in 33 participants (RCMP results: "Success" n = 10, "Failure" n = 15, "Inconclusive" n = 8). In those with a treatment outcome prediction (n = 25) the diagnostic characteristics of the RCMP test were sensitivity 81.8%, specificity 92.9%, positive predictive value 90%, and negative predictive value 86.7% (n = 3 misclassified). The RCMP device was well tolerated by patients and successfully used to perform mandibular protrusion sleep studies in our sleep laboratory. The RCMP sleep study showed good accuracy as a prediction technique for oral appliance treatment outcome, although there was a high rate of inconclusive tests.

  6. Small scale test for seismic response control structure using block & tackle

    Science.gov (United States)

    Zaman, Faisal bin; Suzuki, Yoshiaki; Hayashi, Kazuhiro; Saito, Taiki

    2017-10-01

    An innovative and economic seismic response control system using block and tackle system (hereinafter referred as movable pulley damper system) is under development. In order to clarify the influence of friction between the pulley and the wire, a wire was applied to multiple pulleys and a static force test in which a weight was hung on one side was performed. The frictional force was measured in different test cases by changing the number of loops of the wire and the weight value. If we divide the frictional force by the weight and the number of grooves of pulley, the results show a relatively constant friction coefficient. Then, a dynamic shaking table test using a two story specimen was conducted. Similar to the static test, the frictional force was measured in test cases by changing the number of loops of the wire, the initial tension force of the wire and the amplitude of input sine wave. The obtained friction coefficient was almost the same value of the static test that means the friction coefficient does not change so much between static and dynamic loading conditions.

  7. Respiratory and Cardiovascular Response during Electronic Control Device Exposure in Law Enforcement Trainees

    Science.gov (United States)

    VanMeenen, Kirsten M.; Lavietes, Marc H.; Cherniack, Neil S.; Bergen, Michael T.; Teichman, Ronald; Servatius, Richard J.

    2013-01-01

    Objective: Law enforcement represents a large population of workers who may be exposed to electronic control devices (ECDs). Little is known about the potential effect of exposure to these devices on respiration or cardiovascular response during current discharge. Methods: Participants (N = 23) were trainees exposed to 5 s of an ECD (Taser X26®) as a component of training. Trainees were asked to volitionally inhale during exposure. Respiratory recordings involved a continuous waveform recorded throughout the session including during the exposure period. Heart rate was calculated from a continuous pulse oximetry recording. Results: The exposure period resulted in the cessation of normal breathing patterns in all participants and in particular a decrease in inspiratory activity. No significant changes in heart rate during ECD exposure were found. Conclusion: This is the first study to examine breathing patterns during ECD exposure with the resolution to detect changes over this discrete period of time. In contrast to reports suggesting respiration is unaffected by ECDs, present evidence suggests that voluntary inspiration is severely compromised. There is no evidence of cardiac disruption during ECD exposure. PMID:23616772

  8. Respiratory and cardiovascular response during electronic control device (ECD exposure in law enforcement trainees

    Directory of Open Access Journals (Sweden)

    Kirsten M. VanMeenen

    2013-04-01

    Full Text Available Objective: Law enforcement represents a large population of workers who may be exposed to electronic control devices (ECDs. Little is known about the potential effect of exposure to these devices on respiration or cardiovascular response during current discharge. Methods: Participants (N=23 were trainees exposed to 5 seconds of an ECD (Taser X26® as a component of training. Trainees were asked to volitionally inhale during exposure. Respiratory recordings involved a continuous waveform recorded throughout the session including during the exposure period. Heart rate was calculated from a continuous pulse oximetry recording. Results: The exposure period resulted in the cessation of normal breathing patterns in all participants and in particular a decrease in inspiratory activity. No significant changes in heart rate during ECD exposure were found. Conclusions: This is the first study to examine breathing patterns during ECD exposure with the resolution to detect changes over this discrete period of time. In contrast to reports suggesting respiration is unaffected by ECDs, present evidence suggests that voluntary inspiration is severely compromised. There is no evidence of cardiac disruption during ECD exposure.

  9. Auxin Response Factor SlARF2 Is an Essential Component of the Regulatory Mechanism Controlling Fruit Ripening in Tomato

    OpenAIRE

    Breitel, Dario A.; Louise Chappell-Maor; Sagit Meir; Irina Panizel; Clara Pons Puig; Yanwei Hao; Tamar Yifhar; Hagai Yasuor; Mohamed Zouine; Mondher Bouzayen; Antonio Granell Richart; Ilana Rogachev; Asaph Aharoni

    2016-01-01

    The involvement of ethylene in fruit ripening is well documented, though knowledge regarding the crosstalk between ethylene and other hormones in ripening is lacking. We discovered that AUXIN RESPONSE FACTOR 2A (ARF2A), a recognized auxin signaling component, functions in the control of ripening. ARF2A expression is ripening regulated and reduced in the rin, nor and nr ripening mutants. It is also responsive to exogenous application of ethylene, auxin and abscisic acid (ABA). Over-expressing ...

  10. Volitional control of anticipatory ocular pursuit responses under stabilised image conditions in humans.

    Science.gov (United States)

    Barnes, G; Goodbody, S; Collins, S

    1995-01-01

    Ocular pursuit responses have been examined in humans in three experiments in which the pursuit target image has been fully or partially stabilised on the fovea by feeding a recorded eye movement signal back to drive the target motion. The objective was to establish whether subjects could volitionally control smooth eye movement to reproduce trajectories of target motion in the absence of a concurrent target motion stimulus. In experiment 1 subjects were presented with a target moving with a triangular waveform in the horizontal axis with a frequency of 0.325 Hz and velocities of +/- 10-50 degrees/s. The target was illuminated twice per cycle for pulse durations (PD) of 160-640 ms as it passed through the centre position; otherwise subjects were in darkness. Subjects initially tracked the target motion in a conventional closed-loop mode for four cycles. Prior to the next target presentation the target image was stabilised on the fovea, so that any target motion generated resulted solely from volitional eye movement. Subjects continued to make anticipatory smooth eye movements both to the left and the right with a velocity trajectory similar to that observed in the closed-loop phase. Peak velocity in the stabilised-image mode was highly correlated with that in the prior closed-loop phase, but was slightly less (84% on average). In experiment 2 subjects were presented with a continuously illuminated target that was oscillated sinusoidally at frequencies of 0.2-1.34 Hz and amplitudes of +/- 5-20 degrees. After four cycles of closed-loop stimulation the image was stabilised on the fovea at the time of peak target displacement. Subjects continued to generate an oscillatory smooth eye velocity pattern that mimicked the sinusoidal motion of the previous closed-loop phase for at least three further cycles. The peak eye velocity generated ranged from 57-95% of that in the closed-loop phase at frequencies up to 0.8 Hz but decreased significantly at 1.34 Hz. In experiment 3

  11. On the electrophysiological response of bone cells using a Stokesian fluid stimulus probe for delivery of quantifiable localized picoNewton level forces.

    Science.gov (United States)

    Wu, Danielle; Ganatos, Peter; Spray, David C; Weinbaum, Sheldon

    2011-06-03

    A Stokesian fluid stimulus probe (SFSP), capable of delivering quantifiable pN level hydrodynamic forces, is developed to distinguish the electrophysiological response of the cell process and cell body of osteocyte-like MLO-Y4 cells without touching the cell or its substrate. The hydrodynamic disturbance is a short lived (100 ms), constant strength pressure pulse that propagates nearly instantaneously through the medium creating a nearly spherical expanding fluid bolus surrounding a 0.8 μm micropipette tip. Laboratory model experiments show that the growth of the bolus and the pressure field can be closely modeled by quasi-steady Stokes flow through a circular orifice provided the tip Reynolds number, Re(t)theory. One finds that forces between 1 and 2.3 pN are sufficient to initiate electrical signaling when applied to the cell process, but not the much softer cell body. Even more significantly, cellular excitation by the process only occurs when the probe is directed at discrete focal attachment sites along the cell process. This suggests that electrical signaling is initiated at discrete focal attachments along the cell process and that these sites are likely integrin-mediated complexes associated with stretch-activated ion channels though their molecular structure is unknown. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Effect of montelukast on excessive airway narrowing response to methacholine in adult asthmatic patients not on controller therapy

    DEFF Research Database (Denmark)

    Ulrik, Charlotte Suppli; Diamant, Zuzana

    2009-01-01

    -response plateau to Mtc in adult asthmatic patients not on controller therapy, and, hence, protects against excessive airway narrowing. Thirty-one asthmatic patients (13 male patients, 18-50 years old; forced expiratory volume in 1 second [FEV(1)], >70% predicted; PD(20), ... of treatment with Mont neither induced a plateau response nor affected maximum FEV(1) response or PD(20). Our findings, therefore, suggest that monotherapy with a LTRA does not protect against excessive airway narrowing in adult asthmatic patients not on inhaled corticosteroids....

  13. Effect of montelukast on excessive airway narrowing response to methacholine in adult asthmatic patients not on controller therapy

    DEFF Research Database (Denmark)

    Ulrik, Charlotte Suppli; Diamant, Zuzana

    2009-01-01

    -response plateau to Mtc in adult asthmatic patients not on controller therapy, and, hence, protects against excessive airway narrowing. Thirty-one asthmatic patients (13 male patients, 18-50 years old; forced expiratory volume in 1 second [FEV(1)], >70% predicted; PD(20), ... 2-agonists p.r.n. only with a twice-documented absence of dose-response plateau, participated in a double-blind, parallel study with Mont (10 mg) or placebo once daily for 12 weeks. Mtc dose-response curves (0.03-256 mumol or >40% FEV(1) decline) were repeated every 4 weeks. The primary objective...... of treatment with Mont neither induced a plateau response nor affected maximum FEV(1) response or PD(20). Our findings, therefore, suggest that monotherapy with a LTRA does not protect against excessive airway narrowing in adult asthmatic patients not on inhaled corticosteroids....

  14. Geographic differences in the target-controlled infusion estimated concentration of propofol: bispectral index response curves.

    Science.gov (United States)

    Dahaba, Ashraf A; Zhong, Taidi; Lu, Hui Shun; Bornemann, Helmar; Liebmann, Markus; Wilfinger, Georg; Reibnegger, Gilbert; Metzler, Helfried

    2011-04-01

    Variability in drug responses could result from both genetic and environmental factors. Thus, drug effect could depend on geographic location, although regional variation is not generally acknowledged as a basis for stratification. There is evidence that the pharmacokinetic set developed in a European population for the target-controlled infusion (TCI) of propofol does not apply in Chinese patients; however, we are not aware of previous studies comparing the estimated concentration-bispectral index (BIS) response of Caucasian patients in Europe with that of Chinese patients in China. The Diprifusor™ TCI pump, incorporating the pharmacokinetic model proposed by Marsh et al., was applied to 30 Caucasian patients in Austria and 30 Chinese patients in China. The estimated plasma concentration (C(p)) of propofol for the two groups was set at 1 μg·mL(-1) and increased by 1 μg·mL(-1) every minute to gradually reach 5 μg·mL(-1) after 5 min. The BIS values were fitted against the estimated C(p) and the predicted effect-site concentration (C(e)) in a sigmoid E(max) model. The sigmoid E(max) curves were shifted significantly to the left in the Chinese group compared with the Austrian group. After 5 min, the BIS value in the Chinese group was lower than in the Austrian group (mean ± standard deviation [SD], 47.2 ± 3.6 vs 63.6 ± 5.4, respectively; P = 0.0006). The estimated C(p) at loss of consciousness (LOC), predicted C(e) at LOC, and time to LOC, were lower in the Chinese group than in the Austrian group (3.3 ± 0.8 μg·mL(-1), 1.6 ± 0.4 μg·mL(-1), 2.8 ± 0.6 min, respectively, vs 4.6 ± 2.8 μg·mL(-1), 2.4 ± 1.5 μg·mL(-1), 3.9 ± 0.5 min, respectively; P < 0.0001). When propofol is given using the same TCI protocol, Chinese patients in China lost consciousness faster and at a lower estimated plasma concentration than Caucasians in Austria. Larger studies are needed to map geographically appropriate TCI infusion models.

  15. Trypanosoma cruzi-elicited CD8+ T cell-mediated myocarditis: chemokine receptors and adhesion molecules as potential therapeutic targets to control chronic inflammation?

    Directory of Open Access Journals (Sweden)

    Joseli Lannes-Vieira

    2003-04-01

    Full Text Available In Chagas disease, during the acute phase, the establishment of inflammatory processes is crucial for Trypanosoma cruzi control in target tissues and for the establishment of host/parasite equilibrium. However, in about 30% of the patients, inflammation becomes progressive, resulting in chronic disease, mainly characterized by myocarditis. Although several hypothesis have been raised to explain the pathogenesis of chagasic myocardiopathy, including the persistence of the parasite and/or participation of autoimmune processes, the molecular mechanisms underlying the establishment of the inflammatory process leading to parasitism control but also contributing to the maintenance of T. cruzi-elicited chronic myocarditis remain unsolved. Trying to shed light on these questions, we have for several years been working with murine models for Chagas disease that reproduce the acute self-resolving meningoencephalitis, the encephalitis resulting of reactivation described in immunodeficient individuals, and several aspects of the acute and chronic myocarditis. In the present review, our results are summarized and discussed under the light of the current literature. Furthermore, rational therapeutic intervention strategies based on integrin-mediated adhesion and chemokine receptor-driven recruitment of leukocytes are proposed to control T. cruzi-elicited unbalanced inflammation.

  16. Alcohol-induced impairment of inhibitory control is linked to attenuated brain responses in right fronto-temporal cortex.

    Science.gov (United States)

    Gan, Gabriela; Guevara, Alvaro; Marxen, Michael; Neumann, Maike; Jünger, Elisabeth; Kobiella, Andrea; Mennigen, Eva; Pilhatsch, Maximilian; Schwarz, Daniel; Zimmermann, Ulrich S; Smolka, Michael N

    2014-11-01

    A self-enhancing loop between impaired inhibitory control under alcohol and alcohol consumption has been proposed as a possible mechanism underlying dysfunctional drinking in susceptible people. However, the neural underpinnings of alcohol-induced impairment of inhibitory control are widely unknown. We measured inhibitory control in 50 young adults with a stop-signal task during functional magnetic resonance imaging. In a single-blind placebo-controlled cross-over design, all participants performed the stop-signal task once under alcohol with a breath alcohol concentration of .6 g/kg and once under placebo. In addition, alcohol consumption was assessed with a free-access alcohol self-administration paradigm in the same participants. Inhibitory control was robustly decreased under alcohol compared with placebo, indicated by longer stop-signal reaction times. On the neural level, impaired inhibitory control under alcohol was associated with attenuated brain responses in the right fronto-temporal portion of the inhibition network that supports the attentional capture of infrequent stop-signals and subsequent updating of action plans from response execution to inhibition. Furthermore, the extent of alcohol-induced impairment of inhibitory control predicted free-access alcohol consumption. We suggest that during inhibitory control alcohol affects cognitive processes preceding actual motor inhibition. Under alcohol, decreased brain responses in right fronto-temporal areas might slow down the attentional capture of infrequent stop-signals and subsequent updating of action plans, which leads to impaired inhibitory control. In turn, pronounced alcohol-induced impairment of inhibitory control might enhance alcohol consumption in young adults, which might promote future alcohol problems. Copyright © 2014 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  17. Alcohol-induced impairment of inhibitory control is linked to attenuated brain responses in right fronto-temporal cortex

    Science.gov (United States)

    Gan, Gabriela; Guevara, Alvaro; Marxen, Michael; Neumann, Maike; Jünger, Elisabeth; Kobiella, Andrea; Mennigen, Eva; Pilhatsch, Maximilian; Schwarz, Daniel; Zimmermann, Ulrich S.; Smolka, Michael N.

    2014-01-01

    Background A self-enhancing loop between impaired inhibitory control under alcohol and alcohol consumption has been proposed as a possible mechanism underlying dysfunctional drinking in susceptible people. However, the neural underpinnings of alcohol-induced impairment of inhibitory control are widely unknown. Methods We measured inhibitory control in fifty young adults with a stop-signal task (SST) during functional magnetic resonance imaging (fMRI). In a single-blind placebo-controlled cross-over design, all participants performed the SST once under alcohol with a breath alcohol concentration (BrAC) of 0.6 g/kg, and once under placebo. In addition, alcohol consumption was assessed using a free-access alcohol self-administration (ASA) paradigm in the same participants. Results Inhibitory control was robustly decreased under alcohol compared to placebo indicated by longer stop-signal reaction times (SSRTs). On the neural level, impaired inhibitory control under alcohol was associated with attenuated brain responses in the right fronto-temporal portion of the inhibition network that supports the attentional capture of infrequent stop-signals, and subsequent updating of action plans from response execution to inhibition. Furthermore, the extent of alcohol-induced impairment of inhibitory control predicted free-access alcohol consumption. Conclusion We suggest that during inhibitory control alcohol affects cognitive processes preceding actual motor inhibition. Under alcohol, decreased brain responses in right fronto-temporal areas might slow down the attentional capture of infrequent stop-signals and subsequent updating of action plans which leads to impaired inhibitory control. In turn, pronounced alcohol-induced impairment of inhibitory control may enhance alcohol consumption in young adults which might promote future alcohol problems. PMID:24560581

  18. Application of response surface methodology as a new PID tuning method in an electrocoagulation process control case.

    Science.gov (United States)

    Camcıoğlu, Ş; Özyurt, B; Doğan, I C; Hapoğlu, H

    2017-12-01

    In this work the application of response surface methodology (RSM) to proportional-integral-derivative (PID) controller parameter tuning for electrocoagulation (EC) treatment of pulp and paper mill wastewater was researched. Dynamic data for two controlled variables (pH and electrical conductivity) were obtained under pseudo random binary sequence (PRBS) input signals applied to manipulated variables (acid and supporting electrolyte flow rates). Third order plus time delay model parameters were evaluated through System Identification Toolbox™ in MATLAB®. Four level full factorial design was applied to form a design matrix for three controller tuning parameters as factors and to evaluate statistical analysis of the system in terms of integral of square error (ISE), integral of absolute error (IAE), integral of time square error (ITSE) and integral of time absolute error (ITAE) performance criteria as response. Numerical values of the responses for the runs in the design matrices were determined using closed-loop PID control system simulations designed in Simulink®. Optimum proportional gain, integral action and derivative action values for electrical conductivity control were found to be 1,500 s, 0 s and 16.4636 s respectively. Accordingly, the same optimization scheme was followed for pH control and optimum controller parameters were found to be -8.6970 s, 0.0211 s and 50 s, respectively. Theoretically optimized controller parameters were applied to batch experimental studies. Chemical oxygen demand (COD) removal efficiency and energy consumption of pulp and paper mill wastewater treatment by EC under controlled action of pH at 5.5 and electrical conductivity at 2.72 mS/cm was found to be 85% and 3.87 kWh/m3 respectively. Results showed that multi input-multi output (MIMO) control action increased removal efficiency of COD by 15.41% and reduced energy consumption by 6.52% in comparison with treatment under uncontrolled conditions.

  19. Perceived control moderates the influence of active coping on salivary cortisol response to acute pain among women but not men

    OpenAIRE

    Bento, S.P.; Goodin, B.R.; Fabian, L.A.; Page, G.G; Quinn, N.B.; McGuire, L.

    2010-01-01

    It is generally established that active-coping strategies and greater perceived control over pain are associated with improved pain-related outcomes; however, it remains unclear whether these factors independently or interactively influence adrenocortical function in reaction to a painful stimulus. The present study examined whether active coping predicted magnitude cortisol response to acute pain, whether perceived control over pain moderated this association, and whether effects differed as...

  20. Optimizing the Attitude Control of Small Satellite Constellations for Rapid Response Imaging

    Science.gov (United States)

    Nag, S.; Li, A.

    2016-12-01

    Distributed Space Missions (DSMs) such as formation flight and constellations, are being recognized as important solutions to increase measurement samples over space and time. Given the increasingly accurate attitude control systems emerging in the commercial market, small spacecraft now have the ability to slew and point within few minutes of notice. In spite of hardware development in CubeSats at the payload (e.g. NASA InVEST) and subsystems (e.g. Blue Canyon Technologies), software development for tradespace analysis in constellation design (e.g. Goddard's TAT-C), planning and scheduling development in single spacecraft (e.g. GEO-CAPE) and aerial flight path optimizations for UAVs (e.g. NASA Sensor Web), there is a gap in open-source, open-access software tools for planning and scheduling distributed satellite operations in terms of pointing and observing targets. This paper will demonstrate results from a tool being developed for scheduling pointing operations of narrow field-of-view (FOV) sensors over mission lifetime to maximize metrics such as global coverage and revisit statistics. Past research has shown the need for at least fourteen satellites to cover the Earth globally everyday using a LandSat-like sensor. Increasing the FOV three times reduces the need to four satellites, however adds image distortion and BRDF complexities to the observed reflectance. If narrow FOV sensors on a small satellite constellation were commanded using robust algorithms to slew their sensor dynamically, they would be able to coordinately cover the global landmass much faster without compensating for spatial resolution or BRDF effects. Our algorithm to optimize constellation satellite pointing is based on a dynamic programming approach under the constraints of orbital mechanics and existing attitude control systems for small satellites. As a case study for our algorithm, we minimize the time required to cover the 17000 Landsat images with maximum signal to noise ratio fall

  1. Distinct clpP genes control specific adaptive responses in Bacillus thuringiensis.

    Science.gov (United States)

    Fedhila, Sinda; Msadek, Tarek; Nel, Patricia; Lereclus, Didier

    2002-10-01

    ClpP and ClpC are subunits of the Clp ATP-dependent protease, which is ubiquitous among prokaryotic and eukaryotic organisms. The role of these proteins in stress tolerance, stationary-phase adaptive responses, and virulence in many bacterial species has been demonstrated. Based on the amino acid sequences of the Bacillus subtilis clpC and clpP genes, we identified one clpC gene and two clpP genes (designated clpP1 and clpP2) in Bacillus thuringiensis. Predicted proteins ClpP1 and ClpP2 have approximately 88 and 67% amino acid sequence identity with ClpP of B. subtilis, respectively. Inactivation of clpC in B. thuringiensis impaired sporulation efficiency. The clpP1 and clpP2 mutants were both slightly susceptible to salt stress, whereas disruption of clpP2 negatively affected sporulation and abolished motility. Virulence of the clp mutants was assessed by injecting bacteria into the hemocoel of Bombyx mori larvae. The clpP1 mutant displayed attenuated virulence, which appeared to be related to its inability to grow at low temperature (25 degrees C), suggesting an essential role for ClpP1 in tolerance of low temperature. Microscopic examination of clpP1 mutant cells grown at 25 degrees C showed altered bacterial division, with cells remaining attached after septum formation. Analysis of lacZ transcriptional fusions showed that clpP1 was expressed at 25 and 37 degrees C during the entire growth cycle. In contrast, clpP2 was expressed at 37 degrees C but not at 25 degrees C, suggesting that ClpP2 cannot compensate for the absence of ClpP1 in the clpP1 mutant cells at low temperature. Our study demonstrates that ClpP1 and ClpP2 control distinct cellular regulatory pathways in B. thuringiensis.

  2. Multiple sclerosis patients have a diminished serologic response to vitamin D supplementation compared to healthy controls.

    Science.gov (United States)

    Bhargava, Pavan; Steele, Sonya U; Waubant, Emmanuelle; Revirajan, Nisha R; Marcus, Jacqueline; Dembele, Marieme; Cassard, Sandra D; Hollis, Bruce W; Crainiceanu, Ciprian; Mowry, Ellen M

    2016-05-01

    Vitamin D insufficiency is a risk factor for multiple sclerosis (MS), and patients do not always show the expected response to vitamin D supplementation. We aimed to determine if vitamin D supplementation leads to a similar increase in serum 25-hydroxyvitamin-D (25(OH)D) levels in patients with MS and healthy controls (HCs). Participants in this open-label study were female, white, aged 18-60 years, had 25(OH)D levels ⩽ 75 nmol/l at screening, and had relapsing-remitting MS (RRMS) or were HCs. Participants received 5000 IU/day of vitamin D3 for 90 days. Utilizing generalized estimating equations we examined the relationship between the primary outcome (serum 25(OH)D level) and the primary (MS versus HC status) and secondary predictors. For this study 27 MS patients and 30 HCs were enrolled. There was no significant difference in baseline 25(OH)D level or demographics except for higher body mass index (BMI) in the MS group (25.3 vs. 23.6 kg/m(2), p=0.035). In total, 24 MS subjects and 29 HCs completed the study. In a multivariate model accounting for BMI, medication adherence, and oral contraceptive use, MS patients had a 16.7 nmol/l (95%CI: 4.2, 29.2, p=0.008) lower increase in 25(OH)D levels compared with HCs. Patients with MS had a lower increase in 25(OH)D levels with supplementation, even after accounting for putative confounders. © The Author(s), 2015.

  3. Climatic controls of ecohydrological responses in the highlands of northern Ethiopia.

    Science.gov (United States)

    Tesfaye, Samuale; Birhane, Emiru; Leijnse, Toon; van der Zee, S E A T M

    2017-12-31

    Climate variability and recurrent droughts have a strong negative impact on agricultural production and hydrology in the highlands northern Ethiopia. Since the 1980s, numerous mitigation and land rehabilitation measures have been implemented by local and national authorities to reduce these impacts, are often poorly effective. As underlying reason may be that controlling relationships between climate and ecohydrology at medium-sized catchments (10-10,000km(2)) of semi-arid highlands are not well known. We investigated trends and relationships in precipitation, temperature, streamflow, and net primary productivity (NPP). The results were mixed, with both significant increasing and decreasing trends for temperature and streamflow. Precipitation time series did not show a significant trend for the majority of stations, both over the years and over each season, except for a few stations. A time series indicated a significant abrupt increase of NPP in annual, seasonal and monthly timescale. Cross-correlation and regression analysis indicate precipitation and maximum temperature were the dominant climatic variables in the Geba catchment for streamflow and NPP. In view of these results, also land use and land cover change over the past three decades was analysed as a possible factor of importance, as human intervention, may affect streamflow and NPP. Factors that mainly correlate with streamflow and NPP are precipitation and maximum temperature. Important interventions that appear beneficial for these responses are construction of micro-dams, soil and water conservation and ecological restoration measures. The awareness that interactions can be quite different in semi-arid and semi-humid regions, as well as in upstream and downstream areas, should be reflected in management aimed at sustainable water and land resources use. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Investigating motorists' behaviors in response to supplementary traffic control devices at land surveying work sites.

    Science.gov (United States)

    Yang, Hong; Bartin, Bekir; Ozbay, Kaan; Chien, Steven I-Jy

    2014-01-01

    Since land surveyors working alongside live traffic encounter unique safety challenges there is a great need for innovative and effective traffic control devices (TCDs) that alert motorists approaching short-term land surveying work sites. Unlike the volume of research that has been completed on traditional work zones, however, there is a limited amount of information that has been collected on how motorists respond to TCDs at land surveying work sites. This article aims to fill the void by investigating motorists' behaviors in response to the use of 2 supplementary TCDs at land surveying work sites: portable plastic rumble strips (PPRS) and warning lights. Extensive field tests were conducted at various land surveying work sites on 2-lane 2-way urban roadways in New Jersey. Scenarios with and without the use of the supplemental TCDs were designed. Motorists' behavior changes were then statistically examined by using surrogate safety measures including mean speed, speed variance, speed limit compliance, and braking action. Statistical analyses showed that the traffic speed variations did not significantly increase when the selected supplemental TCD was used; rather, motorists significantly reduced their driving speed. When warning lights and PPRS were separately deployed at the land surveying work sites the average reduction in mean speed was 6.7 and 15.2 percent, respectively. The mean speed was reduced by 19.7 percent when both of these supplementary TCDs were used. Logistic regression models developed to examine the speeding and braking behavior also showed that motorists were more likely to comply with the speed limit and increase their braking rate when the selected TCDs were used. The use of supplemental TCDs can greatly contribute to the changes in motorists' behaviors at surveying work sites. The changes in motorists' driving behaviors imply that the motorists reacted favorably to the deployed TCDs at the land-surveying work sites.

  5. Strong altitudinal control on the response of local glaciers to Holocene climate change in southwest Greenland

    Science.gov (United States)

    Larsen, Nicolaj K.; Strunk, Astrid; Levy, Laura B.; Olsen, Jesper; Bjørk, Anders; Lauridsen, Torben L.; Jeppesen, Erik; Davidson, Thomas A.

    2017-07-01

    Accelerating ice loss during recent years has made the Greenland Ice Sheet one of the largest single contributors to global sea level rise, accounting for 0.5 of the total 3.2 mm yr-1. This loss is predicted to continue and will most likely increase in the future as a consequence of global warming. However, the sensitivity of glaciers and ice caps (GICs) in Greenland to prolonged warm periods is less well constrained and geological records documenting the long-term glacial history are needed to put recent observations into a broader perspective. Here we report the results from three proglacial lakes where fluctuations in local glaciers located at different altitudes in Kobbefjord, southwest Greenland have been recorded. Our results show that the lakes received meltwater from the initial deglaciation of the area ∼9.2 cal. ka BP until ∼8.7-7.9 cal. ka BP when the meltwater input ceased as the glaciers most likely disappeared. Regrowth of glaciers began again at ∼5.5 cal. ka BP at ∼1370 m a.s.l., ∼3.6 cal. ka at ∼1170 m a.s.l., and ∼1.6 cal. ka BP at ∼1000 m a.s.l., clearly reflecting strong altitudinal control of the GIC response to Neoglacial cooling. Our results highlight that GICs in Kobbefjord, southwest Greenland are primarily influenced by changes in summer air temperatures and winter precipitation and that they are facing a rapid decay that most likely will result in their disappearance within the next centuries as a consequence of global warming. If current 21st Century retreat rates continue, the GICs in the study area will be completely gone in ∼30-90 years, with the smallest GICs disappearing first.

  6. Cognitive control during a spatial Stroop task: Comparing conflict monitoring and prediction of response-outcome theories.

    Science.gov (United States)

    Pires, Luís; Leitão, José; Guerrini, Chiara; Simões, Mário R

    2017-07-03

    Cognitive control allows information processing and behaviour to vary adaptively from moment to moment depending on current goals. Two of the most prominent theories that have been proposed to account for the processing of cognitive control are the Conflict Monitoring Theory (CMT) and the Prediction of Response-Outcome Theory (PRO). According to both theories, the implementation of cognitive control during a trial in a conflict task reflects processing events that occurred in the preceding trial. Both CMT and PRO advocate that the detection of conflict situations leads to the recruitment of cognitive control, but they differ regarding the processing underpinnings of cognitive control during conflict resolution. CMT proposes that conflict between alternative responses is resolved by enhancing the task's relevant dimension, reducing interference from the task's irrelevant dimension(s). This control setup promotes conflict adaptation in the subsequent trial. PRO proposes that conflict is resolved by means of a cost-effectiveness analysis that identifies and suppresses action plans linked to the less appropriate responses, facilitating conflict resolution in the subsequent trial. To adjudicate between these alternatives, we manipulated contingencies pertaining to two-trial sequences (n-1; n), namely, the congruency between task relevant/irrelevant dimensions in trial n-1 and response repetition in trial n. A spatial Stroop task was used, in which task-relevant and irrelevant information were integrated within the same stimulus. In this task, participants were required to attend to the direction of an arrow while ignoring its position. The arrow's direction and position could be congruent (C) or incongruent (IC). In one experiment, trials in which the participant was required to respond according to the position of a circle (PO; position only trials), occupying the sequential position n, were the focus of the analyses. Three experiments were conducted manipulating the

  7. Switched Control Strategies of Aggregated Commercial HVAC Systems for Demand Response in Smart Grids

    Directory of Open Access Journals (Sweden)

    Kai Ma

    2017-07-01

    Full Text Available This work proposes three switched control strategies for aggregated heating, ventilation, and air conditioning (HVAC systems in commercial buildings to track the automatic generation control (AGC signal in smart grid. The existing control strategies include the direct load control strategy and the setpoint regulation strategy. The direct load control strategy cannot track the AGC signal when the state of charge (SOC of the aggregated thermostatically controlled loads (TCLs exceeds their regulation capacity, while the setpoint regulation strategy provides flexible regulation capacity, but causes larger tracking errors. To improve the tracking performance, we took the advantages of the two control modes and developed three switched control strategies. The control strategies switch between the direct load control mode and the setpoint regulation mode according to different switching indices. Specifically, we design a discrete-time controller and optimize the controller parameter for the setpoint regulation strategy using the Fibonacci optimization algorithm, enabling us to propose two switched control strategies across multiple time steps. Furthermore, we extend the switched control strategies by introducing a two-stage regulation in a single time step. Simulation results demonstrate that the proposed switched control strategies can reduce the tracking errors for frequency regulation.

  8. When does stress help or harm? The effects of stress controllability and subjective stress response on stroop performance.

    Science.gov (United States)

    Henderson, Roselinde K; Snyder, Hannah R; Gupta, Tina; Banich, Marie T

    2012-01-01

    The ability to engage in goal-directed behavior despite exposure to stress is critical to resilience. Questions of how stress can impair or improve behavioral functioning are important in diverse settings, from athletic competitions to academic testing. Previous research suggests that controllability is a key factor in the impact of stress on behavior: learning how to control stressors buffers people from the negative effects of stress on subsequent cognitively demanding tasks. In addition, research suggests that the impact of stress on cognitive functioning depends on an individual's response to stressors: moderate responses to stress can lead to improved performance while extreme (high or low) responses can lead to impaired performance. The present studies tested the hypothesis that (1) learning to behaviorally control stressors leads to improved performance on a test of general executive functioning, the color-word Stroop, and that (2) this improvement emerges specifically for people who report moderate (subjective) responses to stress. Experiment 1: Stroop performance, measured before and after a stress manipulation, was compared across groups of undergraduate participants (n = 109). People who learned to control a noise stressor and received accurate performance feedback demonstrated reduced Stroop interference compared with people exposed to uncontrollable noise stress and feedback indicating an exaggerated rate of failure. In the group who learned behavioral control, those who reported moderate levels of stress showed the greatest reduction in Stroop interference. In contrast, in the group exposed to uncontrollable events, self-reported stress failed to predict performance. Experiment 2: In a second sample (n = 90), we specifically investigated the role of controllability by keeping the rate of failure feedback constant across groups. In the group who learned behavioral control, those who reported moderate levels of stress showed the greatest Stroop

  9. Interpretation of response categories in patient-reported rating scales: a controlled study among people with Parkinson's disease

    Directory of Open Access Journals (Sweden)

    Knutsson Ida

    2010-06-01

    Full Text Available Abstract Background Unambiguous interpretation of ordered rating scale response categories requires distinct meanings of category labels. Also, summation of item responses into total scores assumes equal intervals between categories. While studies have identified problems with rating scale response category functioning there is a paucity of empirical studies regarding how respondents interpret response categories. We investigated the interpretation of commonly used rating scale response categories and attempted to identify distinct and roughly equally spaced response categories for patient-reported rating scales in Parkinson's disease (PD and age-matched control subjects. Methods Twenty-one rating scale response categories representing frequency, intensity and level of agreement were presented in random order to 51 people with PD (36 men; mean age, 66 years and 36 age-matched controls (14 men; mean age, 66. Respondents indicated their interpretation of each category on 100-mm visual analog scales (VAS anchored by Never - Always, Not at all - Extremely, and Totally disagree - Completely agree. VAS values were compared between groups, and response categories with mean values and non-overlapping 95% CIs corresponding to equally spaced locations on the VAS line were sought to identify the best options for three-, four-, five-, and six-category scales. Results VAS values did not differ between the PD and control samples (P = 0.286 or according to educational level (P = 0.220, age (P = 0.220, self-reported physical functioning (P = 0.501 and mental health (P = 0.238, or (for the PD sample PD duration (P = 0.213 or presence of dyskinesias (P = 0.212. Attempts to identify roughly equally spaced response categories for three-, four-, five-, and six-category scales were unsuccessful, as the 95% CIs of one or several of the identified response categories failed to include the criterion values for equal distances. Conclusions This study offers an evidence

  10. Investigating the Impact of Cognitive Load and Motivation on Response Control in Relation to Delay Discounting in Children with ADHD.

    Science.gov (United States)

    Martinelli, Mary K; Mostofsky, Stewart H; Rosch, Keri S

    2017-10-01

    Attention-deficit/hyperactivity disorder (ADHD) is characterized by deficits in impulse control across a range of behaviors, from simple actions to those involving complex decision-making (e.g., preference for smaller-sooner versus larger later rewards). This study investigated whether changes in motor response control with increased cognitive load and motivational contingencies are associated with decision-making in the form of delay discounting among 8-12 year old children with and without ADHD. Children with ADHD (n = 26; 8 girls) and typically developing controls (n = 40; 11 girls) completed a standard go/no-go (GNG) task, a GNG task with motivational contingencies, a GNG task with increased cognitive load, and two measures of delay discounting: a real-time task in which the delays and immediately consumable rewards are experienced in real-time, and a classic task involving choices about money at longer delays. Children with ADHD, particularly girls, exhibited greater delay discounting than controls during the real-time discounting task, whereas diagnostic groups did not significantly differ on the classic discounting task. The effect of cognitive load on response control was uniquely associated with greater discounting on the real-time task for children with ADHD, but not for control children. The effect of motivational contingencies on response control was not significantly associated with delay discounting for either diagnostic group. The findings from this study help to inform our understanding of the factors that influence deficient self-control in ADHD, suggesting that impairments in cognitive control may contribute to greater delay discounting in ADHD.

  11. Linear frequency tuning in an LC-resonant system using a C-V response controllable MEMS varactor

    Science.gov (United States)

    Han, Chang-Hoon; Yoon, Yong-Hoon; Ko, Seung-Deok; Seo, Min-Ho; Yoon, Jun-Bo

    2017-12-01

    This paper proposes a device level solution to achieve linear frequency tuning with respect to a tuning voltage ( V tune ) sweep in an inductor ( L)-capacitor ( C) resonant system. Since the linearity of the resonant frequency vs. tuning voltage ( f- V) relationship in an LC-resonant system is closely related to the C- V response characteristic of the varactor, we propose a C- V response tunable varactor to realize the linear frequency tuning. The proposed varactor was fabricated using microelectromechanical system (MEMS) surface micromachining. The fabricated MEMS varactor has the ability to dynamically change the C- V response characteristic according to a curve control voltage ( V curve- control ). When V curve- control was increased from zero to 9 V, the C- V response curve was changed from a linear to a concave form (i.e., the capacitance decreased quickly in the low tuning voltage region and slowly in the high tuning voltage region). This change in the C- V response characteristic resulted in a change in the f- V relationship, and we successfully demonstrated almost perfectly linear frequency tuning in the LC-resonant system, with a linearity factor of 99.95%.

  12. When does stress help or harm? The effects of stress controllability and subjective stress response on Stroop performance.

    Directory of Open Access Journals (Sweden)

    Roselinde Kaiser Henderson

    2012-06-01

    Full Text Available The ability to engage in goal-directed behavior despite exposure to stress is critical to resilience. Questions of how stress can impair or improve behavioral functioning are important in diverse settings, from athletic competitions to academic testing to clinical therapy. Previous research suggests that controllability is a key factor in the impact of stress on behavior: learning how to control stressors buffers people from the negative effects of stress on subsequent cognitively demanding tasks. In addition, research suggests that the impact of stress on cognitive functioning depends on an individual’s response to stressors: moderate responses to stress can lead to improved performance while extreme (high or low responses can lead to impaired performance. The present studies tested the hypothesis that 1 learning to behaviorally control stressors leads to improved performance on a test of general executive functioning, the color-word Stroop, and that 2 this improvement emerges specifically for people who report moderate (subjective responses to stress. Experiment 1: Stroop performance, measured before and after a stress manipulation, was compared across groups of undergraduate participants (n=109. People who learned to control a noise stressor and received accurate performance feedback demonstrated reduced Stroop interference compared with people exposed to uncontrollable noise stress and feedback indicating an exaggerated rate of failure. In the group who learned behavioral control, those who reported moderate levels of stress showed the greatest reduction in Stroop interference. In contrast, in the group exposed to uncontrollable events, self-reported stress failed to predict performance. Experiment 2: In a second sample (n=90, we specifically investigated the role of controllability by keeping the rate of failure feedback constant across groups. In the group who learned behavioral control, those who reported moderate levels of stress

  13. Functional brain response to food images in successful adolescent weight losers compared with normal-weight and overweight controls.

    Science.gov (United States)

    Jensen, Chad D; Kirwan, C Brock

    2015-03-01

    Research conducted with adults suggests that successful weight losers demonstrate greater activation in brain regions associated with executive control in response to viewing high-energy foods. No previous studies have examined these associations in adolescents. Functional neuroimaging was used to assess brain response to food images among groups of overweight (OW), normal-weight (NW), and successful weight-losing (SWL) adolescents. Eleven SWL, 12 NW, and 11 OW participants underwent functional magnetic resonance imaging while viewing images of high- and low-energy foods. When viewing high-energy food images, SWLs demonstrated greater activation in the dorsolateral prefrontal cortex (DLPFC) compared with OW and NW controls. Compared with NW and SWL groups, OW individuals demonstrated greater activation in the ventral striatum and anterior cingulate in response to food images. Adolescent SWLs demonstrated greater neural activation in the DLPFC compared with OW/NW controls when viewing high-energy food stimuli, which may indicate enhanced executive control. OW individuals' brain responses to food stimuli may indicate greater reward incentive processes than either SWL or NW groups. © 2015 The Obesity Society.

  14. Specific predictive power of automatic spider-related affective associations for controllable and uncontrollable fear responses toward spiders

    NARCIS (Netherlands)

    J. Huijding (Jorg); P.J. de Jong (Peter)

    2006-01-01

    textabstractThis study examined the predictive power of automatically activated spider-related affective associations for automatic and controllable fear responses. The Extrinsic Affective Simon Task (EAST; De Houwer, 2003) was used to indirectly assess automatic spider fear-related associations.

  15. Adult height in children with growth hormone deficiency: a randomized, controlled, growth hormone dose-response trial.

    NARCIS (Netherlands)

    Sas, T.C.J.; Ridder, M.A. de; Wit, J.M.; Rotteveel, J.J.; Oostdijk, W.; Reeser, H.M.; Otten, B.J.; Muinck Keizer-Schrama, S.M.P.F. de

    2010-01-01

    AIM: To investigate the effect of 2 growth hormone (GH) doses on adult height (AH) in GH deficiency (GHD). METHODS: A multicenter, randomized, controlled dose-response trial compared attained AH minus target height (TH) between children receiving 0.7 mg/m(2)/day biosynthetic GH (approx. 0.025

  16. Adult Height in Children with Growth Hormone Deficiency: A Randomized, Controlled, Growth Hormone Dose-Response Trial

    NARCIS (Netherlands)

    Sas, T.C.J.; de Ridder, M.A.J.; Wit, J.M.; Rotteveel, J.; Oostdijk, W.; Reeser, H.M.; Otten, B.J.; Keizer-Schrama, S.M.P.F.

    2010-01-01

    Aim: To investigate the effect of 2 growth hormone (GH) doses on adult height (AH) in GH deficiency (GHD). Methods: A multicenter, randomized, controlled dose-response trial compared attained AH minus target height (TH) between children receiving 0.7 mg/m

  17. DMPD: DUSP meet immunology: dual specificity MAPK phosphatases in control of theinflammatory response. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 17114416 DUSP meet immunology: dual specificity MAPK phosphatases in control of the...inflammatory response. Lang R, Hammer M, Mages J. J Immunol. 2006 Dec 1;177(11):7497-504. (.png) (.svg) (.html) (.csml) Show DUSP mee...onse. PubmedID 17114416 Title DUSP meet immunology: dual specificity MAPK phospha

  18. Radiotherapy for spinal metastases from breast cancer with emphasis on local disease control and pain response using repeated MRI

    Directory of Open Access Journals (Sweden)

    Marta D. Switlyk

    2014-03-01

    Conclusion: RT provided excellent local tumor control in patients with SM. Most patients benefit from RT even in cases of progressive vertebral fracture. Pain response was not associated with imaging findings and MRI cannot be used to select patients at risk of not responding to RT.

  19. Utility and Cost-Effectiveness of Motivational Messaging to Increase Survey Response in Physicians: A Randomized Controlled Trial

    Science.gov (United States)

    Chan, Randolph C. H.; Mak, Winnie W. S.; Pang, Ingrid H. Y.; Wong, Samuel Y. S.; Tang, Wai Kwong; Lau, Joseph T. F.; Woo, Jean; Lee, Diana T. F.; Cheung, Fanny M.

    2018-01-01

    The present study examined whether, when, and how motivational messaging can boost the response rate of postal surveys for physicians based on Higgin's regulatory focus theory, accounting for its cost-effectiveness. A three-arm, blinded, randomized controlled design was used. A total of 3,270 doctors were randomly selected from the registration…

  20. Comparison of analytical and wind-tunnel results for flutter and gust response of a transport wing with active controls

    Science.gov (United States)

    Abel, I.; Perry, B., III; Newsom, J. R.

    1982-01-01

    Two flutter suppression control laws wre designed and tested on a low speed aeroelastic model of a DC-10 derivative wing. Both control laws demontrated increases in flutter speed in excess of 25 percent above the passive wing flutter speed. In addition, one of the control laws was effective in reducing loads due to turbulence generated in the wind tunnel. The effect of variations in gain and phase on the closed-loop performance was measured and is compared with predictions. In general, both flutter and gust response predictions agree reasonably well with experimental data.

  1. Optimal Bounded Control for Stationary Response of Strongly Nonlinear Oscillators under Combined Harmonic and Wide-Band Noise Excitations

    Directory of Open Access Journals (Sweden)

    Yongjun Wu

    2011-01-01

    Full Text Available We study the stochastic optimal bounded control for minimizing the stationary response of strongly nonlinear oscillators under combined harmonic and wide-band noise excitations. The stochastic averaging method and the dynamical programming principle are combined to obtain the fully averaged Itô stochastic differential equations which describe the original controlled strongly nonlinear system approximately. The stationary joint probability density of the amplitude and phase difference of the optimally controlled systems is obtained from solving the corresponding reduced Fokker-Planck-Kolmogorov (FPK equation. An example is given to illustrate the proposed procedure, and the theoretical results are verified by Monte Carlo simulation.

  2. Genome-wide gene expression profiling of stress response in a spinal cord clip compression injury model

    Science.gov (United States)

    2013-01-01

    Background The aneurysm clip impact-compression model of spinal cord injury (SCI) is a standard injury model in animals that closely mimics the primary mechanism of most human injuries: acute impact and persisting compression. Its histo-pathological and behavioural outcomes are extensively similar to human SCI. To understand the distinct molecular events underlying this injury model we analyzed global mRNA abundance changes during the acute, subacute and chronic stages of a moderate to severe injury to the rat spinal cord. Results Time-series expression analyses resulted in clustering of the majority of deregulated transcripts into eight statistically significant expression profiles. Systematic application of Gene Ontology (GO) enrichment pathway analysis allowed inference of biological processes participating in SCI pathology. Temporal analysis identified events specific to and common between acute, subacute and chronic time-points. Processes common to all phases of injury include blood coagulation, cellular extravasation, leukocyte cell-cell adhesion, the integrin-mediated signaling pathway, cytokine production and secretion, neutrophil chemotaxis, phagocytosis, response to hypoxia and reactive oxygen species, angiogenesis, apoptosis, inflammatory processes and ossification. Importantly, various elements of adaptive and induced innate immune responses span, not only the acute and subacute phases, but also persist throughout the chronic phase of SCI. Induced innate responses, such as Toll-like receptor signaling, are more active during the acute phase but persist throughout the chronic phase. However, adaptive immune response processes such as B and T cell activation, proliferation, and migration, T cell differentiation, B and T cell receptor-mediated signaling, and B cell- and immunoglobulin-mediated immune response become more significant during the chronic phase. Conclusions This analysis showed that, surprisingly, the diverse series of molecular events that

  3. Cardiorespiratory control and cytokine profile in response to heat stress, hypoxia, and lipopolysaccharide (LPS) exposure during early neonatal period.

    Science.gov (United States)

    McDonald, Fiona B; Chandrasekharan, Kumaran; Wilson, Richard J A; Hasan, Shabih U

    2016-02-01

    Sudden infant death syndrome (SIDS) is one of the most common causes of postneonatal infant mortality in the developed world. An insufficient cardiorespiratory response to multiple environmental stressors (such as prone sleeping positioning, overwrapping, and infection), during a critical period of development in a vulnerable infant, may result in SIDS. However, the effect of multiple risk factors on cardiorespiratory responses has rarely been tested experimentally. Therefore, this study aimed to quantify the independent and possible interactive effects of infection, hyperthermia, and hypoxia on cardiorespiratory control in rats during the neonatal period. We hypothesized that lipopolysaccharide (LPS) administration will negatively impact cardiorespiratory responses to increased ambient temperature and hypoxia in neonatal rats. Sprague-Dawley neonatal rat pups were studied at postnatal day 6-8. Rats were examined at an ambient temperature of 33°C or 38°C. Within each group, rats were allocated to control, saline, or LPS (200 μg/kg) treatments. Cardiorespiratory and thermal responses were recorded and analyzed before, during, and after a hypoxic exposure (10% O2). Serum samples were taken at the end of each experiment to measure cytokine concentrations. LPS significantly increased cytokine concentrations (such as TNFα, IL-1β, MCP-1, and IL-10) compared to control. Our results do not support a three-way interaction between experimental factors on cardiorespiratory control. However, independently, heat stress decreased minute ventilation during normoxia and increased the hypoxic ventilatory response. Furthermore, LPS decreased hypoxia-induced tachycardia. Herein, we provide an extensive serum cytokine profile under various experimental conditions and new evidence that neonatal cardiorespiratory responses are adversely affected by dual interactions of environmental stress factors. © 2016 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on

  4. Ovarian response to controlled ovarian hyperstimulation : What does serum FSH say?

    NARCIS (Netherlands)

    Oudshoorn, Simone C.; Van Tilborg, Theodora C.; Hamdine, Ouijdane; Torrance, Helen L.; Eijkemans, Marinus J.C.; Lentjes, Eef G.W.M.; Lambalk, Cornelis B.; Broekmans, Frank J.M.

    2017-01-01

    STUDY QUESTION Do serum FSH levels on day of hCG trigger differ between women with a poor, normal or hyper response to a fixed daily dose of 150 IU recombinant FSH (rFSH)? SUMMARY ANSWER There is no consistent relationship between ovarian response and serum FSH levels on day of hCG trigger in a 150

  5. Intestinal Monocyte-Derived Macrophages Control Commensal-Specific Th17 Responses

    Directory of Open Access Journals (Sweden)

    Casandra Panea

    2015-08-01

    Full Text Available Generation of different CD4 T cell responses to commensal and pathogenic bacteria is crucial for maintaining a healthy gut environment, but the associated cellular mechanisms are poorly understood. Dendritic cells (DCs and macrophages (Mfs integrate microbial signals and direct adaptive immunity. Although the role of DCs in initiating T cell responses is well appreciated, how Mfs contribute to the generation of CD4 T cell responses to intestinal microbes is unclear. Th17 cells are critical for mucosal immune protection and at steady state are induced by commensal bacteria, such as segmented filamentous bacteria (SFB. Here, we examined the roles of mucosal DCs and Mfs in Th17 induction by SFB in vivo. We show that Mfs, and not conventional CD103+ DCs, are essential for the generation of SFB-specific Th17 responses. Thus, Mfs drive mucosal T cell responses to certain commensal bacteria.

  6. Key factors controlling microbial community response after a fire: importance of severity and recurrence

    Science.gov (United States)

    Lombao, Alba; Barreiro, Ana; Martín, Ángela; Díaz-Raviña, Montserrat

    2015-04-01

    Microorganisms play an important role in forest ecosystems, especially after fire when vegetation is destroyed and soil is bared. Fire severity and recurrence might be one of main factors controlling the microbial response after a wildfire but information about this topic is scarce. The aim of this study is to evaluate the influence of fire regimen (recurrence and severity) on soil microbial community structure by means of the analysis of phospholipid fatty acid (PLFA). The study was performed with unburned and burned samples collected from the top layer of a soil affected by a high severity fire (Laza, NW Spain) heated under laboratory conditions at different temperatures (50°C, 75°C, 100°C, 125°C, 150°C, 175°C, 200°C, 300°C) to simulate different fire intensities; the process was repeated after further soil recovery (1 month incubation) to simulate fire recurrence. The soil temperature was measured with thermocouples and used to calculate the degree-hours as estimation of the amount of heat supplied to the samples (fire severity). The PLFA analysis was used to estimate total biomass and the biomass of specific groups (bacteria, fungi, gram-positive bacteria and gram-negative bacteria) as well as microbial community structure (PLFA pattern) and PLFA data were analyzed by means of principal component analysis (PCA) in order to identify main factors determining microbial community structure. The results of PCA, performed with the whole PLFA data set, showed that first component explained 35% of variation and clearly allow us to differentiate unburned samples from the corresponding burned samples, while the second component, explaining 16% of variation, separated samples according the heating temperature. A marked impact of fire regimen on soil microorganisms was detected; the microbial community response varied depending on previous history of soil heating and the magnitude of changes in the PLFA pattern was related to the amount of heat supplied to the

  7. Effects of working memory training on neural correlates of Go/Nogo response control in adults with ADHD: A randomized controlled trial.

    Science.gov (United States)

    Liu, Zhong-Xu; Lishak, Victoria; Tannock, Rosemary; Woltering, Steven

    2017-01-27

    Working memory and response control are conceptualized as functions that are part of a closely connected and integrated executive function system mediated by the prefrontal cortex and other related brain structures. In the present paper, we asked whether effects of intensive and adaptive computerized working memory training (CWMT) would generalize to enhancements in response control at behavioral and neural levels. A total of 135 postsecondary students with Attention-Deficit/Hyperactivity Disorder (ADHD), a condition associated with executive function impairments, were randomized into a Standard-length CWMT (45-min /session, 25 sessions), Shortened-length CWMT (15min/session, 25 sessions), and a waitlist group. Both training groups received CWMT for 5 days a week for 5 weeks long. All participants completed a Go-Nogo task while neural activity was measured using Electroencephalography (EEG), before and after CWMT. Behavioral results showed trend level evidence (p=0.061) for benefits of CWMT on response control (i.e., improved accuracy of Go responses). Among several neural measures results showed statistically significant changes after CWMT only for the Go trial ERP N2 and P3 in frontal electrodes (p=0.039 and 0.001, respectively). However, given the lack of relationship between behavioral and neural changes and especially the clear lack of predicted does effects (i.e., standard length > short length > control), we conclude that there is no convincing evidence that the working memory training per se changes neural activation patterns in untrained executive functions. The positive finding of general training related changes in this study should have no clinical implications, but may contribute to the literature in better understanding the relationship between neural plasticity and transfer. Published by Elsevier Ltd.

  8. A randomised controlled trial to determine the effect on response of including a lottery incentive in health surveys [ISRCTN32203485

    Science.gov (United States)

    Roberts, LM; Wilson, S; Roalfe, A; Bridge, P

    2004-01-01

    Background Postal questionnaires are an economical and simple method of data collection for research purposes but are subject to non-response bias. Several studies have explored the effect of monetary and non-monetary incentives on response. Recent meta-analyses conclude that financial incentives are an effective way of increasing response rates. However, large surveys rarely have the resources to reward individual participants. Three previous papers report on the effectiveness of lottery incentives with contradictory results. This study aimed to determine the effect of including a lottery-style incentive on response rates to a postal health survey. Methods Randomised controlled trial. Setting: North and West Birmingham. 8,645 patients aged 18 or over randomly selected from registers of eight general practices (family physician practices). Intervention: Inclusion of a flyer and letter with a health questionnaire informing patients that returned questionnaires would be entered into a lottery-style draw for £100 of gift vouchers. Control: Health questionnaire accompanied only by standard letter of explanation. Main outcome measures: Response rate and completion rate to questionnaire. Results 5,209 individuals responded with identical rates in both groups (62.1%). Practice, patient age, sex and Townsend score (a postcode based deprivation measure) were identified as predictive of response, with higher response related to older age, being female and living in an area with a lower Townsend score (less deprived). Conclusion This RCT, using a large community based sample, found that the offer of entry into a lottery style draw for £100 of High Street vouchers has no effect on response rates to a postal health questionnaire. PMID:15533256

  9. A randomised controlled trial to determine the effect on response of including a lottery incentive in health surveys [ISRCTN32203485

    Directory of Open Access Journals (Sweden)

    Bridge P

    2004-11-01

    Full Text Available Abstract Background Postal questionnaires are an economical and simple method of data collection for research purposes but are subject to non-response bias. Several studies have explored the effect of monetary and non-monetary incentives on response. Recent meta-analyses conclude that financial incentives are an effective way of increasing response rates. However, large surveys rarely have the resources to reward individual participants. Three previous papers report on the effectiveness of lottery incentives with contradictory results. This study aimed to determine the effect of including a lottery-style incentive on response rates to a postal health survey. Methods Randomised controlled trial. Setting: North and West Birmingham. 8,645 patients aged 18 or over randomly selected from registers of eight general practices (family physician practices. Intervention: Inclusion of a flyer and letter with a health questionnaire informing patients that returned questionnaires would be entered into a lottery-style draw for £100 of gift vouchers. Control: Health questionnaire accompanied only by standard letter of explanation. Main outcome measures: Response rate and completion rate to questionnaire. Results 5,209 individuals responded with identical rates in both groups (62.1%. Practice, patient age, sex and Townsend score (a postcode based deprivation measure were identified as predictive of response, with higher response related to older age, being female and living in an area with a lower Townsend score (less deprived. Conclusion This RCT, using a large community based sample, found that the offer of entry into a lottery style draw for £100 of High Street vouchers has no effect on response rates to a postal health questionnaire.

  10. Thermal response simulation for tuning PID controllers in a 1016 mm guarded hot plate apparatus.

    Science.gov (United States)

    Thomas, William C; Zarr, Robert R

    2011-07-01

    A mathematical model has been developed and used to simulate the controlled thermal performance of a large guarded hot-plate apparatus. This highly specialized apparatus comprises three interdependent components whose temperatures are closely controlled in order to measure the thermal conductivity of insulation materials. The simulation model was used to investigate control strategies and derive controller gain parameters that are directly transferable to the actual instrument. The simulations take orders-of-magnitude less time to carry out when compared to traditional tuning methods based on operating the actual apparatus. The control system consists primarily of a PC-based PID control algorithm that regulates the output voltage of programmable power amplifiers. Feedback parameters in the form of controller gains are required for the three heating circuits. An objective is to determine an improved set of gains that meet temperature control criteria for testing insulation materials of interest. The analytical model is based on aggregated thermal capacity representations of the primary components and includes the same control algorithm as used in the actual hot-plate apparatus. The model, accounting for both thermal characteristics and temperature control, was validated by comparisons with test data. The tuning methodology used with the simulation model is described and results are presented. The resulting control algorithm and gain parameters have been used in the actual apparatus without modification during several years of testing materials over wide ranges of thermal conductivity, thickness, and insulation resistance values. Published by Elsevier Ltd on behalf of ISA.

  11. Flight control of fruit flies: dynamic response to optic flow and headwind.

    Science.gov (United States)

    Lawson, Kiaran K K; Srinivasan, Mandyam V

    2017-06-01

    Insects are magnificent fliers that are capable of performing many complex tasks such as speed regulation, smooth landings and collision avoidance, even though their computational abilities are limited by their small brain. To investigate how flying insects respond to changes in wind speed and surrounding optic flow, the open-loop sensorimotor response of female Queensland fruit flies ( Bactrocera tryoni ) was examined. A total of 136 flies were exposed to stimuli comprising sinusoidally varying optic flow and air flow (simulating forward movement) under tethered conditions in a virtual reality arena. Two responses were measured: the thrust and the abdomen pitch. The dynamics of the responses to optic flow and air flow were measured at various frequencies, and modelled as a multicompartment linear system, which accurately captured the behavioural responses of the fruit flies. The results indicate that these two behavioural responses are concurrently sensitive to changes of optic flow as well as wind. The abdomen pitch showed a streamlining response, where the abdomen was raised higher as the magnitude of either stimulus was increased. The thrust, in contrast, exhibited a counter-phase response where maximum thrust occurred when the optic flow or wind flow was at a minimum, indicating that the flies were attempting to maintain an ideal flight speed. When the changes in the wind and optic flow were in phase (i.e. did not contradict each other), the net responses (thrust and abdomen pitch) were well approximated by an equally weighted sum of the responses to the individual stimuli. However, when the optic flow and wind stimuli were presented in counterphase, the flies seemed to respond to only one stimulus or the other, demonstrating a form of 'selective attention'. © 2017. Published by The Company of Biologists Ltd.

  12. Hypothalamic BOLD response to glucose intake and hypothalamic volume are similar in anorexia nervosa and healthy control subjects

    Directory of Open Access Journals (Sweden)

    Anna M Van Opstal

    2015-05-01

    Full Text Available Background. Inconsistent findings about the neurobiology of Anorexia Nervosa (AN hinder the development of effective treatments for this severe mental disorder. Therefore the need arises for elucidation of neurobiological factors involved in the pathophysiology of AN. The hypothalamus plays a key role in the neurobiological processes that govern food intake and energy homeostasis, processes that are disturbed in anorexia nervosa (AN. The present study will assess the hypothalamic response to energy intake and the hypothalamic structure in patients with AN and healthy controls. Methods. 10 women aged 18-30 years diagnosed with AN and 11 healthy, lean (BMI <23 kg/m2 women in the same age range were recruited. We used functional magnetic resonance imaging (MRI to determine function of the hypothalamus in response to glucose. Structural MRI was used to determine differences in hypothalamic volume and local grey volume using manual segmentation and voxel-based morphometry.Results. No differences were found in hypothalamic volume and neuronal activity in response to a glucose load between the patients and controls. Whole brain structural analysis showed a significant decrease in grey matter volume in the cingulate cortex in the AN patients, bilaterally.Conclusions. We argue that in spite of various known changes in the hypothalamus the direct hypothalamic response to glucose intake is similar in AN patients and healthy controls.

  13. Closed-loop control of zebrafish response using a bioinspired robotic-fish in a preference test.

    Science.gov (United States)

    Kopman, Vladislav; Laut, Jeffrey; Polverino, Giovanni; Porfiri, Maurizio

    2013-01-06

    In this paper, we study the response of zebrafish to a robotic-fish whose morphology and colour pattern are inspired by zebrafish. Experiments are conducted in a three-chambered instrumented water tank where a robotic-fish is juxtaposed with an empty compartment, and the preference of live subjects is scored as the mean time spent in the vicinity of the tank's two lateral sides. The tail-beating of the robotic-fish is controlled in real-time based on feedback from fish motion to explore a spectrum of closed-loop systems, including proportional and integral controllers. Closed-loop control systems are complemented by open-loop strategies, wherein the tail-beat of the robotic-fish is independent of the fish motion. The preference space and the locomotory patterns of fish for each experimental condition are analysed and compared to understand the influence of real-time closed-loop control on zebrafish response. The results of this study show that zebrafish respond differently to the pattern of tail-beating motion executed by the robotic-fish. Specifically, the preference and behaviour of zebrafish depend on whether the robotic-fish tail-beating frequency is controlled as a function of fish motion and how such closed-loop control is implemented.

  14. Ethylene-mediated cross-talk between calcium-dependent protein kinase and MAPK signaling controls stress responses in plants.

    Science.gov (United States)

    Ludwig, Andrea A; Saitoh, Hiromasa; Felix, Georg; Freymark, Gerald; Miersch, Otto; Wasternack, Claus; Boller, Thomas; Jones, Jonathan D G; Romeis, Tina

    2005-07-26

    Plants are constantly exposed to environmental changes and need to integrate multiple external stress cues. Calcium-dependent protein kinases (CDPKs) are implicated as major primary Ca2+ sensors in plants. CDPK activation, like activation of mitogen-activated protein kinases (MAPKs), is triggered by biotic and abiotic stresses, although distinct stimulus-specific stress responses are induced. To investigate whether CDPKs are part of an underlying mechanism to guarantee response specificity, we identified CDPK-controlled signaling pathways. A truncated form of Nicotiana tabacum CDPK2 lacking its regulatory autoinhibitor and calcium-binding domains was ectopically expressed in Nicotiana benthamiana. Infiltrated leaves responded to an abiotic stress stimulus with the activation of biotic stress reactions. These responses included synthesis of reactive oxygen species, defense gene induction, and SGT1-dependent cell death. Furthermore, N-terminal CDPK2 signaling triggered enhanced levels of the phytohormones jasmonic acid, 12-oxo-phytodienoic acid, and ethylene but not salicylic acid. These responses, commonly only observed after challenge with a strong biotic stimulus, were prevented when the CDPK's intrinsic autoinhibitory peptide was coexpressed. Remarkably, elevated CDPK signaling compromised stress-induced MAPK activation, and this inhibition required ethylene synthesis and perception. These data indicate that CDPK and MAPK pathways do not function independently and that a concerted activation of both pathways controls response specificity to biotic and abiotic stress.

  15. The impact of attentional training on the salivary cortisol and alpha amylase response to psychosocial stress: importance of attentional control.

    Science.gov (United States)

    Pilgrim, Kamala; Ellenbogen, Mark A; Paquin, Karine

    2014-06-01

    This study examined the effects of three consecutive days of attentional training on the salivary alpha amylase (sAA), cortisol, and mood response to the Trier Social Stress Test (TSST). The training was designed to elicit faster disengagement of attention away from threatening facial expressions and faster shifts of attention toward positive ones. Fifty-six healthy participants between the ages of 18 and 30 participated in a double-blind, within-subject experiment. Participants were randomly assigned to one of three attentional training conditions - supraliminal training: pictures shown with full conscious awareness, masked training: stimuli presented with limited conscious awareness, or control training: both supraliminal and masked pictures shown but no shifting of attention required. Following training, participants underwent the TSST. Self-reported mood and saliva samples were collected for the determination of emotional reactivity, cortisol, and sAA in response to stress post-training. Unexpectedly, participants in both attentional training groups exhibited a higher salivary cortisol response to the TSST relative to participants who underwent the control training, F (4, 86)=4.07, p=.005, ηp(2)=.16. Supraliminal training was also associated with enhanced sAA reactivity, F (2, 44)=13.90, p=.000, ηp(2)=.38, and a more hostile mood response (p=.021), to the TSST. Interestingly, the effect of attention training on the cortisol response to stress was more robust in those with high attentional control than those with low attentional control (β=-0.134; t=-2.24, p=.03). This is among the first experimental manipulations to demonstrate that attentional training can elicit a paradoxical increase in three different markers of stress reactivity. These findings suggest that attentional training, in certain individuals, can have iatrogenic effects. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Creb and Sp/Krüppel response elements cooperate to control rat TRH gene transcription in response to cAMP.

    Science.gov (United States)

    Cote-Vélez, Antonieta; Pérez-Maldonado, Adrián; Osuna, Joel; Barrera, Benito; Charli, Jean-Louis; Joseph-Bravo, Patricia

    2011-03-01

    Expression of hypophysiotropic TRH, that controls thyroid axis activity, is increased by cold exposure; this effect is mimicked in rat hypothalamic cells incubated with norepinephrine or cAMP analogs. TRH proximal promoter contains three putative CRE: Site-4 or CRE-1 that overlaps an element recognized by thyroid hormone receptors, CRE-2 with adjacent sequences GC box or CACCC recognized by Sp/Krüppel factors (extended CRE-2), and AP-1 sites flanking a GRE(1/2). To evaluate the role of each element in the cAMP response, these sites were mutated or deleted in rat TRH promoter linked to luciferase gene (TRH-luc) and co-transfected with β-gal expression vector in various cell lines; C6 cells gave the highest response to forskolin. Basal activity was most affected by mutations or deletion of CRE-2 site, or CACCC (50-75% of wild type-WT). Forskolin-induced 3× stimulation in WT which decreased 25% with CRE-1 or AP-1 deletions, but 50% when CRE-2 or its 5' adjacent GC box was altered. SH-SY5Y cells co-transfected with CREB-expression vector increased dB-cAMP response in the wild type but not in the CRE-2 mutated plasmid; cotransfecting CREB-A (a dominant negative expression vector) strongly diminished basal or cAMP response. Primary cultures of hypothalamic cells transfected with plasmids containing deletions of CRE-1, CRE-2, or extended CRE-2 failed to respond to forskolin when CRE-2 was modified. These results corroborate the CRE-2 site as the main cAMP-response element of rat TRH promoter, not exclusive of transcription factors of hypothalamic cells, and stress the relevance of adjacent Sp-1 sites, important mediators of some metabolic hormones. Published by Elsevier B.V.

  17. Asparagine endopeptidase controls anti-influenza virus immune responses through TLR7 activation

    National Research Council Canada - National Science Library

    Maschalidi, Sophia; Hässler, Signe; Blanc, Fany; Sepulveda, Fernando E; Tohme, Mira; Chignard, Michel; van Endert, Peter; Si-Tahar, Mustapha; Descamps, Delphyne; Manoury, Bénédicte

    2012-01-01

    .... Here we report that asparagine endopeptidase (AEP) deficient mice are unable to generate a strong anti-IAV response, as demonstrated by reduced inflammation, cross presentation of cell-associated antigens and priming of CD8...

  18. Paradoxical response preceding control of Scedosporium apiospermum mycetoma with posaconazole treatment.

    Science.gov (United States)

    Béraud, Guillaume; Desbois, Nicole; Coyo, Caroline; Quist, Danièle; Rozé, Benoit; Savorit, Luc; Cabié, André

    2015-01-01

    Mycetoma is a chronic granulomatous infection that is difficult to treat, notably when due to fungi such as Scedosporium apiospermum. Recent antifungal agents could be an option, but cases are rarely reported, and none with posaconazole. Paradoxical responses, defined as initial clinical worsening despite appropriate treatment, are common in tuberculosis but rare in deep mycoses in non-immunocompromised hosts. Hence, paradoxical responses in context other than mycobacterial infection in an immunocompromised host could provide insights into the pathophysiology and the optimal strategy for treatment. We report the first case of a mycetoma caused by S. apiospermum with bone involvement treated with posaconazole, and the paradoxical response observed at the beginning of the treatment. As with mycobacterial infections, a paradoxical response in deep mycosis could represent the earliest marker of therapeutic efficacy.

  19. Changing the Rules: Innovative Low-Energy Occupant-Responsive HVAC Controls and Systems

    OpenAIRE

    Bauman, Fred; Raftery, Paul; Kim, Joyce; Kaam, Soazig; Schiavon, Stefano; Zhang, Hui; Arens, Edward; Brown, Karl; Peffer, Therese; Blumstein , Carl; Culler, David; Andersen, Michael; Fierro, Gabe; Paliaga, Gwelen; Pande, Abhijeet

    2017-01-01

    The overall goal of this Project was to create a new occupant-based paradigm for Heating, Ventilation, and Air Conditioning (HVAC) control that will reduce HVAC energy use in buildings while improving occupant comfort. The Project explored integrating low-energy personal comfort systems (PCS) into HVAC operations, advanced variable-air volume (VAV) control algorithms, and innovative open-source software for monitoring and control. The Project investigated deployment of commercially available ...

  20. Reference values in ovarian response to controlled ovarian stimulation throughout the reproductive period.

    Science.gov (United States)

    La Marca, Antonio; Grisendi, Valentina; Spada, Elena; Argento, Cindy; Milani, Silvano; Plebani, Maddalena; Seracchioli, Renato; Volpe, Annibale

    2014-01-01

    Abstract The age-related decline in ovarian response to gonadotropins has been well known since the beginning of ovarian stimulation in IVF cycles and has been considered secondary to the age-related decline in ovarian reserve. The objective of this study was to establish reference values and to construct nomograms of ovarian response for any specific age to gonadotropins in IVF/ICSI cycles. We analyzed our database containing information on IVF cycles. According to inclusion and exclusion criteria, a total of 703 patients were selected. Among inclusion criteria, there were regular menstrual cycle, treatment with a long GnRH agonist protocol and starting follicle-stimulating hormone (FSH) dose of at least 200 IU per day. To estimate the reference values of ovarian response, the CG-LMS method was used. A linear decline in the parameters of ovarian response with age was observed: the median number of oocytes decreases approximately by one every three years, and the median number of follicles >16 mm by one every eight years. The number of oocytes and growing follicles corresponding to the 5th, 25th, 50th, 75th and 95th centiles has been calculated. This study confirmed the well known negative relationship between ovarian response to FSH and female ageing and permitted the construction of nomograms of ovarian response.

  1. Enzyme Sequestration as a Tuning Point in Controlling Response Dynamics of Signalling Networks.

    Directory of Open Access Journals (Sweden)

    Song Feng

    2016-05-01

    Full Text Available Signalling networks result from combinatorial interactions among many enzymes and scaffolding proteins. These complex systems generate response dynamics that are often essential for correct decision-making in cells. Uncovering biochemical design principles that underpin such response dynamics is a prerequisite to understand evolved signalling networks and to design synthetic ones. Here, we use in silico evolution to explore the possible biochemical design space for signalling networks displaying ultrasensitive and adaptive response dynamics. By running evolutionary simulations mimicking different biochemical scenarios, we find that enzyme sequestration emerges as a key mechanism for enabling such dynamics. Inspired by these findings, and to test the role of sequestration, we design a generic, minimalist model of a signalling cycle, featuring two enzymes and a single scaffolding protein. We show that this simple system is capable of displaying both ultrasensitive and adaptive response dynamics. Furthermore, we find that tuning the concentration or kinetics of the sequestering protein can shift system dynamics between these two response types. These empirical results suggest that enzyme sequestration through scaffolding proteins is exploited by evolution to generate diverse response dynamics in signalling networks and could provide an engineering point in synthetic biology applications.

  2. Trusted Interconnections Between a Centralized Controller and Commercial Building HVAC Systems for Reliable Demand Response

    National Research Council Canada - National Science Library

    Jones, C. Birk; Carter, Cedric

    2017-01-01

    .... Increased operability can be achieved using a secure and reliable interconnection device, which can provide direct bidirectional communications between the utility and the building automation system (BAS) controllers...

  3. Different Optimal Control Strategies for Exploitation of Demand Response in the Smart Grid

    DEFF Research Database (Denmark)

    Zong, Yi; Bindner, Henrik W.; Gehrke, Oliver

    2012-01-01

    resources, intermittent renewable energy resources in the Smart Grid. This paper presents different optimal control (Genetic Algorithm-based and Model Predictive Control-based) algorithms that schedule controlled loads in the industrial and residential sectors, based on dynamic price and weather forecast......, considering users’ comfort settings to meet an optimization objective, such as maximum profit or minimum energy consumption. It is demonstrated in this work that the GA-based and MPC-based optimal control strategies are able to achieve load shifting for grid reliability and energy savings, including demand...

  4. Modafinil increases the latency of response in the Hayling Sentence Completion Test in healthy volunteers: a randomised controlled trial.

    Directory of Open Access Journals (Sweden)

    Ahmed Dahir Mohamed

    Full Text Available Modafinil is a medication licensed for the treatment of narcolepsy. However, it has been reported that healthy individuals without wakefulness disorders are using modafinil off-label to enhance cognitive functioning. Although some studies have reported that modafinil improves cognitive task performance in healthy volunteers, numerous other studies have failed to detect cognitive enhancing effects of modafinil on several well-established neuropsychological tasks. Interestingly, several clinical and preclinical studies have found that improved cognitive task performance by modafinil is accompanied by slower response times. This observation raises the question as to whether this slowing of response time in healthy volunteers is a necessary and sufficient condition for cognitive enhancement with modafinil. The aim of the current experiment was to explore this question by investigating the effects of modafinil on the Hayling Sentence Completion Test (HSCT.Sixty-four healthy volunteers received either a single dose (200 mg of modafinil (n = 32 or placebo (n = 32 in a randomized, double-blind, placebo-controlled, parallel group study in which the principal outcome measures were response latencies on the response initiation and response inhibition sections of the HSCT.Participants dosed with modafinil had significantly longer mean response latencies on the HSCT for both the response initiation and response inhibition compared to participants dosed with placebo. However, participants in both groups made a similar number of errors on each of these measures, indicating that modafinil did not enhance the accuracy of performance of the task relative to placebo.This study demonstrated that administration of single 200 mg doses of modafinil to healthy individuals increased the latency of responses in the performance of the HSCT, a task that is highly sensitive to prefrontal executive function, without enhancing accuracy of performance. This finding may

  5. Modafinil increases the latency of response in the Hayling Sentence Completion Test in healthy volunteers: a randomised controlled trial.

    Science.gov (United States)

    Mohamed, Ahmed Dahir; Lewis, Chris Roberts

    2014-01-01

    Modafinil is a medication licensed for the treatment of narcolepsy. However, it has been reported that healthy individuals without wakefulness disorders are using modafinil off-label to enhance cognitive functioning. Although some studies have reported that modafinil improves cognitive task performance in healthy volunteers, numerous other studies have failed to detect cognitive enhancing effects of modafinil on several well-established neuropsychological tasks. Interestingly, several clinical and preclinical studies have found that improved cognitive task performance by modafinil is accompanied by slower response times. This observation raises the question as to whether this slowing of response time in healthy volunteers is a necessary and sufficient condition for cognitive enhancement with modafinil. The aim of the current experiment was to explore this question by investigating the effects of modafinil on the Hayling Sentence Completion Test (HSCT). Sixty-four healthy volunteers received either a single dose (200 mg) of modafinil (n = 32) or placebo (n = 32) in a randomized, double-blind, placebo-controlled, parallel group study in which the principal outcome measures were response latencies on the response initiation and response inhibition sections of the HSCT. Participants dosed with modafinil had significantly longer mean response latencies on the HSCT for both the response initiation and response inhibition compared to participants dosed with placebo. However, participants in both groups made a similar number of errors on each of these measures, indicating that modafinil did not enhance the accuracy of performance of the task relative to placebo. This study demonstrated that administration of single 200 mg doses of modafinil to healthy individuals increased the latency of responses in the performance of the HSCT, a task that is highly sensitive to prefrontal executive function, without enhancing accuracy of performance. This finding may provide

  6. Learned helplessness and learned effectiveness: effects of explicit response cues on individuals differing in personal control expectancies.

    Science.gov (United States)

    Gregory, W L; Chartier, G M; Wright, M H

    1979-11-01

    Female undergraduates (n = 62) who scored as extreme internals or externals on the Mirels Personal Fate Control Scale participated in a partial replication of Hiroto's learned helplessness experiment. Lights were added to the treatment apparatus, which made explicit to subjects the contingency or noncontingency between their responses and the termination of an aversive tone. As predicted, the performance of internals was significantly impaired by uncontrollability (learned helplessness), while that of externals was facilitated by controllability (learned effectiveness). Externals performed as well as internals in the "escapable" condition, but their performance was inferior to that of internals in the control condition. Following "inescapable" treatment, internals performed worse than externals. These results are supportive of Lefcourt's theory of cue explication. Implications for locus of control and learned helplessness research are discussed.

  7. Miniature proportional control valve with top-mounted piezo bimorph actuator with millisecond response time

    NARCIS (Netherlands)

    Groen, Maarten; Brouwer, Dannis Michel; Lötters, Joost Conrad; Wiegerink, Remco J.

    2015-01-01

    In this paper we demonstrate the realization of a micro control valve with a top-mounted piezoelectric bimorph actuator, to obtain a high-bandwidth proportional control valve for gases in the range of several grams per hour. Dynamic fluidic and mechanical characterization shows that the valve is

  8. Genetic control of plasticity in root morphology and anatomy of rice in response to water deficit

    NARCIS (Netherlands)

    Kadam, Niteen N.; Tamilselvan, Anandhan; Lawas, Lovely M.F.; Quinones, Cherryl; Bahuguna, Rajeev N.; Thomson, Michael J.; Dingkuhn, Michael; Muthurajan, Raveendran; Struik, Paul C.; Yin, Xinyou; Jagadish, Krishna S.V.

    2017-01-01

    Elucidating the genetic control of rooting behavior under water-deficit stress is essential to breed climate-robust rice (Oryza sativa) cultivars. Using a diverse panel of 274 indica genotypes grown under control and water-deficit conditions during vegetative growth, we phenotyped 35 traits, mostly

  9. A Frequency Response Approach to Sliding Control Design for Hydraulic Drives

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Johansen, Per; Andersen, Torben Ole

    2014-01-01

    . However, when considering hydraulic cylinder drives, such full state feedback may not be available, and alternative approaches to conventional methods may be considered. This issue is addressed in this paper in regard to tracking control design for valve controlled hydraulic cylinder drives, and a design...

  10. Analysis of pilot response time to time-critical air traffic control calls

    Science.gov (United States)

    1991-08-01

    One of the most important time-critical air traffic control messages for a pilot is one : that required an immediate maneuver for traffic avoidance. This study examines the time : required for an air traffic controller to successfully transmit such a...

  11. 42 CFR 456.4 - Responsibility for monitoring the utilization control program.

    Science.gov (United States)

    2010-10-01

    ... these methods and procedures on file; and (5) Give copies of these methods and procedures to all staff... control program. 456.4 Section 456.4 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL ASSISTANCE PROGRAMS UTILIZATION CONTROL General Provisions...

  12. Overvoltage Mitigation Using Coordinated Control of Demand Response and Grid-tied Photovoltaics

    DEFF Research Database (Denmark)

    Bhattarai, Bishnu Prasad; Bak-Jensen, Birgitte; Pillai, Jayakrishnan Radhakrishna

    2015-01-01

    Overvoltages in low voltage distribution grids with high solar photovoltaic (PV) integration are usually alleviated by implementing various active/reactive power control techniques. As those methods create revenue loss or inverter cost increase to PV owners, a coordinated control of load demand...

  13. Fuzzy predictive filtering in nonlinear economic model predictive control for demand response

    DEFF Research Database (Denmark)

    Santos, Rui Mirra; Zong, Yi; Sousa, Joao M. C.

    2016-01-01

    The performance of a model predictive controller (MPC) is highly correlated with the model's accuracy. This paper introduces an economic model predictive control (EMPC) scheme based on a nonlinear model, which uses a branch-and-bound tree search for solving the inherent non-convex optimization...... problem. Moreover, to reduce the computation time and improve the controller's performance, a fuzzy predictive filter is introduced. With the purpose of testing the developed EMPC, a simulation controlling the temperature levels of an intelligent office building (PowerFlexHouse), with and without fuzzy...... filtering, is performed. The results show that the controller achieves a good performance while keeping the temperature inside the predefined comfort limits. Fuzzy predictive filtering has shown to be an effective tool which is capable of reducing the computational burden and increasing the performance...

  14. Effects of method and format on subjects' responses to a control of variables reasoning problem

    Science.gov (United States)

    Staver, John R.

    Excessive time and training demands have rendered Piaget's clinical method of reasoning assessment impractical for researchers and science teachers who work with large numbers of students. The published literature[Note ][See: Lawson, A. E. Journal of Research in Science Teaching, 1978, 15(1), 11-24; Shayer, M., Adey, P., & Wylam, H. Journal of Research in Science Teaching, 1981, 18(2), 157-168; Staver, J. R., & Gabel, D. L. Journal of Research in Science Teaching, 1979, 16(6), 534-544; Tobin, K. G., & Capie, W. Educational and Psychological Measurement, 1981, 41(2), 413-424.] indicates that reliable, valid alternatives to clinical assessment are feasible. However, the overestimate/underestimate of reasoning for different methods and formats remains unresolved through research. The objective of this study was to determine the effects of various methods and formats on subjects' responses to a Piagetian reasoning problem requiring control of variables. The task chosen for this investigation was the Mealworm problem.[Note ][See: Karplus, R., Lawson, A., Wollman, W., Appel, M., Bernoff, R., Howe, A., Rusch, J., & Sullivan, F. Science teaching and the development of reasoning. Berkeley, CA: University of California, 1977.] The task was presented by three methods: (1) individual clinical interview; (2) group presentation of task followed by paper-and-pencil problem with illustration; and (3) group administration of paper-and-pencil instrument with illustration. Each method included four formats: (1) completion answer with essay justification; (2) completion answer with multiplechoice justification; (3) multiple-choice answer with essay justification; and (4) multiple-choice answer with multiple-choice justification. Two hundred and fifty-three (253) students who were enrolled in a freshman level biological science class participated in the study. The research design was a 3 × 4 factorial design with method and format of assessment as the main effects. The participants

  15. Genetic control of the variable innate immune response to asymptomatic bacteriuria.

    Directory of Open Access Journals (Sweden)

    Jenny Grönberg-Hernández

    Full Text Available The severity of urinary tract infection (UTI reflects the quality and magnitude of the host response. While strong local and systemic innate immune activation occurs in patients with acute pyelonephritis, the response to asymptomatic bacteriuria (ABU is low. The immune response repertoire in ABU has not been characterized, due to the inherent problem to distinguish bacterial differences from host-determined variation. In this study, we investigated the host response to ABU and genetic variants affecting innate immune signaling and UTI susceptibility. Patients were subjected to therapeutic urinary tract inoculation with E. coli 83972 to ensure that they were exposed to the same E. coli strain. The innate immune response repertoire was characterized in urine samples, collected from each patient before and after inoculation with bacteria or PBS, if during the placebo arm of the study. Long-term E. coli 83972 ABU was established in 23 participants, who were followed for up to twelve months and the innate immune response was quantified in 233 urine samples. Neutrophil numbers increased in all but two patients and in an extended urine cytokine/chemokine analysis (31 proteins, the chemoattractants IL-8 and GRO-α, RANTES, Eotaxin-1 and MCP-1, the T cell chemoattractant and antibacterial peptide IP-10, inflammatory regulators IL-1-α and sIL-1RA and the T lymphocyte/dendritic cell product sIL-2Rα were detected and variably increased, compared to sterile samples. IL-6, which is associated with symptomatic UTI, remained low and numerous specific immune mediators were not detected. The patients were also genotyped for UTI-associated IRF3 and TLR4 promoter polymorphisms. Patients with ABU associated TLR4 polymorphisms had low neutrophil numbers, IL-6, IP-10, MCP-1 and sIL-2Rα concentrations. Patients with the ABU-associated IRF3 genotype had lower neutrophils, IL-6 and MCP-1 responses than the remaining group. The results suggest that the host

  16. Improved aircraft dynamic response and fatigue life during ground operations using an active control landing gear system

    Science.gov (United States)

    Mcgehee, J. R.; Carden, H. D.; Edson, R.

    1978-01-01

    A three-degree-of-freedom aircraft landing analysis incorporating a series-hydraulic active control main landing gear has been developed and verified using preliminary experimental data from drop tests of a modified main landing gear from a 2722 kg (6000 lbm) class of airplane. The verified analysis was also employed to predict the landing dynamics of a supersonic research airplane with an active control main landing gear system. The results of this investigation have shown that this type of active gear is feasible and indicate a potential for improving airplane dynamic response and reducing structural fatigue damage during ground operations by approximately 90% relative to that incurred with the passive gear.

  17. Long noncoding RNA #32 contributes to antiviral responses by controlling interferon-stimulated gene expression.

    Science.gov (United States)

    Nishitsuji, Hironori; Ujino, Saneyuki; Yoshio, Sachiyo; Sugiyama, Masaya; Mizokami, Masashi; Kanto, Tatsuya; Shimotohno, Kunitada

    2016-09-13

    Despite the breadth of knowledge that exists regarding the function of long noncoding RNAs (lncRNAs) in biological phenomena, the role of lncRNAs in host antiviral responses is poorly understood. Here, we report that lncRNA#32 is associated with type I IFN signaling. The silencing of lncRNA#32 dramatically reduced the level of IFN-stimulated gene (ISG) expression, resulting in sensitivity to encephalomyocarditis virus (EMCV) infection. In contrast, the ectopic expression of lncRNA#32 significantly suppressed EMCV replication, suggesting that lncRNA#32 positively regulates the host antiviral response. We further demonstrated the suppressive function of lncRNA#32 in hepatitis B virus and hepatitis C virus infection. lncRNA#32 bound to activating transcription factor 2 (ATF2) and regulated ISG expression. Our results reveal a role for lncRNA#32 in host antiviral responses.

  18. A colony-level response to disease control in a leaf-cutting ant

    Science.gov (United States)

    Hart, Adam; Bot, A. N. M.; Brown, Mark

    2002-03-01

    Parasites and pathogens often impose significant costs on their hosts. This is particularly true for social organisms, where the genetic structure of groups and the accumulation of contaminated waste facilitate disease transmission. In response, hosts have evolved many mechanisms of defence against parasites. Here we present evidence that Atta colombica, a leaf-cutting ant, may combat Escovopsis, a dangerous parasite of Atta's garden fungus, through a colony-level behavioural response. In A. colombica, garden waste is removed from within the colony and transported to the midden - an external waste dump - where it is processed by a group of midden workers. We found that colonies infected with Escovopsis have higher numbers of workers on the midden, where Escovopsis is deposited. Further, midden workers are highly effective in dispersing newly deposited waste away from the dumping site. Thus, the colony-level task allocation strategies of the Atta superorganism may change in response to the threat of disease to a third, essential party.

  19. Tuning magnetic response of epitaxial iron-silicide nanoislands by controlled self-assembled growth

    Science.gov (United States)

    Goldfarb, I.; Camus, Y.; Dascalu, M.; Cesura, F.; Chalasani, R.; Kohn, A.

    2017-07-01

    We investigated the dependence of the magnetic response from epitaxial Si-rich iron-silicide nanostructures on their geometry. By varying substrate orientation and deposition parameters, we altered the growth kinetics and the lattice matching conditions at the silicide/silicon interface. These affected the silicide nanoisland crystal structure, size, shape, and proximity due to spatial ordering and, consequently, their magnetic response in terms of shape and opening of the respective hysteresis loops. In particular, we demonstrated correlation between magnetic anisotropy, expressed as the hysteresis coercive field, and the nanoisland spatial length-to-width aspect ratio. This correlation is explained by the contribution of undercoordinated island edge atoms to the overall measured magnetic behavior of the nanoisland arrays. Further, the island self-ordering along periodic surface steps adds dipolar interactions between the otherwise superparamagnetic nanoislands, consequently resulting in a magnetic response resembling that of a superspin glass.

  20. Dynamic Responses and Vibration Control of the Transmission Tower-Line System: A State-of-the-Art Review

    Science.gov (United States)

    Chen, Bo; Guo, Wei-hua; Li, Peng-yun; Xie, Wen-ping

    2014-01-01

    This paper presented an overview on the dynamic analysis and control of the transmission tower-line system in the past forty years. The challenges and future developing trends in the dynamic analysis and mitigation of the transmission tower-line system under dynamic excitations are also put forward. It also reviews the analytical models and approaches of the transmission tower, transmission lines, and transmission tower-line systems, respectively, which contain the theoretical model, finite element (FE) model and the equivalent model; shows the advances in wind responses of the transmission tower-line system, which contains the dynamic effects under common wind loading, tornado, downburst, and typhoon; and discusses the dynamic responses under earthquake and ice loads, respectively. The vibration control of the transmission tower-line system is also reviewed, which includes the magnetorheological dampers, friction dampers, tuned mass dampers, and pounding tuned mass dampers. PMID:25105161

  1. Assessing stimulus control and promoting generalization via video modeling when teaching social responses to children with autism.

    Science.gov (United States)

    Jones, JoAnna; Lerman, Dorothea C; Lechago, Sarah

    2014-01-01

    We taught social responses to young children with autism using an adult as the recipient of the social interaction and then assessed generalization of performance to adults and peers who had not participated in the training. Although the participants' performance was similar across adults, responding was less consistent with peers, and a subsequent probe suggested that the recipient of the social behavior (adults vs. peers) controlled responding. We then evaluated the effects of having participants observe a video of a peer engaged in the targeted social behavior with another peer who provided reinforcement for the social response. Results suggested that certain irrelevant stimuli (adult vs. peer recipient) were more likely to exert stimulus control over responding than others (setting, materials) and that video viewing was an efficient way to promote generalization to peers. © Society for the Experimental Analysis of Behavior.

  2. Dynamic responses and vibration control of the transmission tower-line system: a state-of-the-art review.

    Science.gov (United States)

    Chen, Bo; Guo, Wei-hua; Li, Peng-yun; Xie, Wen-ping

    2014-01-01

    This paper presented an overview on the dynamic analysis and control of the transmission tower-line system in the past forty years. The challenges and future developing trends in the dynamic analysis and mitigation of the transmission tower-line system under dynamic excitations are also put forward. It also reviews the analytical models and approaches of the transmission tower, transmission lines, and transmission tower-line systems, respectively, which contain the theoretical model, finite element (FE) model and the equivalent model; shows the advances in wind responses of the transmission tower-line system, which contains the dynamic effects under common wind loading, tornado, downburst, and typhoon; an