998 resultados para Vehicle-bridge interaction


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The virus inducible non-coding RNA (VINC) was detected initially in the brain of mice infected with Japanese encephalitis virus (JEV) and rabies virus. VINC is also known as NEAT1 or Men epsilon RNA. It is localized in the nuclear paraspeckles of several murine as well as human cell lines and is essential for paraspeckle formation. We demonstrate that VINC interacts with the paraspeckle protein, P54nrb through three different protein interaction regions (PIRs) one of which (PIR-1) is localized near the 50 end while the other two (PIR-2, PIR-3) are localized near the 30 region of VINC. Our studies suggest that VINC may interact with P54nrb through a novel mechanism which is different from that reported for protein coding RNAs. (C) 2010 Federation of European Biochemical Societies. Published by Elsevier B. V. All rights reserved.

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"Body and Iron: Essays on the Socialness of Objects" focuses on the bodily-material interaction of human subjects and technical objects. It poses a question, how is it possible that objects have an impact on their human users and examines the preconditions of active efficacy of objects. In this theoretical task the work relies on various discussions drawing from realistic ontology, phenomenology of body, neurophysiology of Antonio Damasio and psychoanalysis to establish both objects and bodies as material entities related in a causal interaction with each other. Out of material interaction emerge a symbolic field, psyche and culture that produce representations of interactions with material world they remain dependent on and conditioned by. Interaction with objects informs the human body via its somatosensory systems: interoseptive and proprioseptive (or kinesthetic) systems provide information to central nervous system of the internal state of the body and muscle tensions and motor activity of the limbs. Capability to control the movements of one's body by the internal "feel" of being a body turns out to be a precondition to the ability to control artificial extensions of the body. Motor activity of the body is involved in every perception of environment as the feel of one's own body is constitutive of any perception of external objects. Perception of an object cause changes in the internal milieu of the body and these changes in the organism form a bodily representation of an external object. Via these "muscle images" the subject can develop a feel for an instrument. Bodily feel for an object is pre-conceptual, practical knowledge that resists articulation but allows sensing the world through the object. This is what I would call sensual knowledge. Technical objects intervene between body and environment, transforming the relation of perception and motor activity. Once connected to a vehicle, human subject has to calibrate visual information of his or her position and movement in space to the bodily actions controlling the machine. It is the machine that mediates the relation of human actions to the relation of her body to its environment. Learning to use the machine necessarily means adjusting his or her bodily actions to the responses of the machine in relation to environmental changes it causes. Responsiveness of the machine to human touch "teaches" its subject by providing feedback of the "correctitude" of his or her bodily actions. Correct actions form a body technique of handling the object. This is the way of socialness of objects. While responding to human actions they generate their subjects. Learning to handle a machine means accepting the position of the user in the program of action materialized in the construction of the object. Objects mediate, channel and transform the relation of the body to its environment and via environment to the body itself according to their material and technical construction. Objects are sensory media: they channel signals and information from the environment thus constituting a representation of environment, a virtual or artificial reality. They also feed the body directly with their powers equipping their user with means of regulating somatic and psychic states of her self. For these reasons humans look for the company of objects. Keywords: material objects, material culture, sociology of technology, sociology of body, mobility, driving

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This report presents evidence for the interactions of several classes of cationic amphiphilic drugs including the phenothiazines, aminoquinolines, biguanides, and aromatic diamidines, with lipid A, the endotoxic principle of lipopolysaccharides. The interactions of the drugs were quantitatively assessed by fluorescence methods. The affinities of the drugs for lipid A parallel their endotoxin-antagonistic effects in the Limulus gelation assay. Dicationic compounds bind lipid A with greater affinity; the affinity of such molecules increases exponentially as a function of the distance between the basic moieties. The bis-amidine drug - pentamidine - examined in greater detail, binds lipid A with high affinity (apparent K-d: 0.12 mu M), and LPS, probably due to simultaneous interactions of the terminal amidine groups with the anionic phosphates on lipid A. The sequestration of endotoxin by pentamidine reduces its propensity to bind to cells, and the complex exhibits attenuated toxicity in biological assays. These results have implications in the development of therapeutic strategies against endotoxin-related disease states.

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The interactions of lipid A and lipopolysaccharide (LPS) with human serum albumin (HSA) were examined using fluorescence methods. Lipid A binds HSA with a stoichiometry of 2:1 with dissociation constants of 1.0 µM and 6.0 µM for the high- and low-affinity interactions, respectively. Lipid A displaces HSA-bound dansylsarcosine competitively, but not HSA-bound warfarin, suggesting that domain III-A, and not domain 11-A, is a lipid A binding site. Domain I does not contribute a site for lipid A. Based on these data, and the structural similarity between subdomains III-A and III-B, it is proposed that these two regions of HSA represent the high- and low-affinity sites of interaction of lipid A. Whole LPS also binds HSA, displacing dansylsarcosine, and its lipid A moiety appears to be the interaction site. However, there are differences between LPS and free lipid A. Polymyxin B forms ternary complexes with LPS bound to HSA, suggesting that the regions on LPS recognized by HSA and polymyxin B are different. The observed affinity of lipid A for HSA and mass action effects due to its abundance in the circulation would imply a major LPS carrier function for HSA.

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The future of civic engagement is characterised by both technological innovation as well as new technological user practices that are fuelled by trends towards mobile, personal devices; broadband connectivity; open data; urban interfaces; and cloud computing. These technology trends are progressing at a rapid pace, and have led global technology vendors to package and sell the “Smart City” as a centralised service delivery platform predicted to optimise and enhance cities’ key performance indicators – and generate a profitable market. The top-down deployment of these large and proprietary technology platforms have helped sectors such as energy, transport, and healthcare to increase efficiencies. However, an increasing number of scholars and commentators warn of another “IT bubble” emerging. Along with some city leaders, they argue that the top-down approach does not fit the governance dynamics and values of a liberal democracy when applied across sectors. A thorough understanding is required, of the socio-cultural nuances of how people work, live, play across different environments, and how they employ social media and mobile devices to interact with, engage in, and constitute public realms. Although the term “slacktivism” is sometimes used to denote a watered down version of civic engagement and activism that is reduced to clicking a “Like” button and signing online petitions, we believe that we are far from witnessing another Biedermeier period that saw people focus on the domestic and the non-political. There is plenty of evidence to the contrary, such as post-election violence in Kenya in 2008, the Occupy movements in New York, Hong Kong and elsewhere, the Arab Spring, Stuttgart 21, Fukushima, the Taksim Gezi Park in Istanbul, and the Vinegar Movement in Brazil in 2013. These examples of civic action shape the dynamics of governments, and in turn, call for new processes to be incorporated into governance structures. Participatory research into these new processes across the triad of people, place and technology is a significant and timely investment to foster productive, sustainable, and liveable human habitats. With this article, we want to reframe the current debates in academia and priorities in industry and government to allow citizens and civic actors to take their rightful centrepiece place in civic movements. This calls for new participatory approaches for co-inquiry and co-design. It is an evolving process with an explicit agenda to facilitate change, and we propose participatory action research (PAR) as an indispensable component in the journey to develop new governance infrastructures and practices for civic engagement. We do not limit our definition of civic technologies to tools specifically designed to simply enhance government and governance, such as renewing your car registration online or casting your vote electronically on election day. Rather, we are interested in civic media and technologies that foster citizen engagement in the widest sense, and particularly the participatory design of such civic technologies that strive to involve citizens in political debate and action as well as question conventional approaches to political issues. The rationale for this approach is an alternative to smart cities in a “perpetual tomorrow,” based on many weak and strong signals of civic actions revolving around technology seen today. It seeks to emphasise and direct attention to active citizenry over passive consumerism, human actors over human factors, culture over infrastructure, and prosperity over efficiency. First, we will have a look at some fundamental issues arising from applying simplistic smart city visions to the kind of a problem a city poses. We focus on the touch points between “the city” and its civic body, the citizens. In order to provide for meaningful civic engagement, the city must provide appropriate interfaces.

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This study analyzes civic activity, citizenship and their gendered manifestations in contemporary Russia. It is based on a case study conducted in the city of Tver , located in the vicinity of Moscow, during 2001-2005. The data consists of interviews with civic activists and municipal and regional authorities; observations of civic organizations; and a quantitative survey conducted among local civic groups. The theoretical and methodological framework of the study draws upon a micro perspective on organization, discourse analysis, gender and citizenship theories and Pierre Bourdieu s theory of fields and capital. This study develops theoretical understanding of the characteristics and logic of civic organization in Russia. It shows that social class centrally structures the field of civic activity. Organizations can be seen as a vehicle of the educated class to advocate their interests, help themselves and seek both social and individual-level change. The study also argues that civic organizations founded during the post-Soviet era are often an institutionalized form of informal social networks. Networks, which were a central element of everyday interaction in Soviet society, are a resource and often the only resource available that can be made use of in contemporary organizational activities. The study argues that gender operates as a key structuring principle in the Russian socio-political community. Civic activity is often discursively associated with femininity and institutional politics with masculinity. Women tend to participate more than men in civic organizations, while men dominate the formal political domain. The study shows that civic organizations are important loci of communality. This communality, however, differs from the communality envisioned in the communitarian and social capital debates in the West. It is selective communality , as it is restricted to the members of the organizations and does not create generalized reciprocity and trust. Civic organizations tend to build upon and reproduce the traditional Russian organizational form of circles , kruzhki. Along with the analysis of civic activities, the study also examines the redefinition of the role and functions of the state. The authorities interviewed in this study understand civic organizations as serving those goals and interests determined by the authorities, instead of viewing them as sites of citizens self-organization around interests and problems citizens themselves deem important, or as a counterforce to the state. By contrast, civic activists understand the core of organizational activity to be advocacy of their interests and rights, tackling social problems, the pursuit of wider social change and self-help. Co-operation between authorities and organizations tends to be personified and based upon unequal, hierarchical patron-client arrangements, which inhibits the development of democratic governance. The study will be published in Routledge Contemporary Russia and Eastern Europe Series later this year.

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Oil droplets are dispersed in water by an anionic urfactant to form an emulsion. The lubricity of this emulsion in steel/steel interaction is explored in a ball on flat nanotribometer. The droplet size and charge are measured using dynamic light scattering, while the substrate charge density is estimated using the pH titration method. These data are combined to calculate the DLVO forces for the droplets generated for a range of surfactant concentration and two oil to water volume ratios. The droplets have a clear bi-modal size distribution. The study shows that the smaller droplets which experience weak repulsion are situated (at the highest DLVO barrier) much closer to the substrate than thebigger droplets, which experience the same DLVO force, are. We suggest that the smaller droplets thus play a more important role in lubricity than what the bigger droplets do. The largest volume of such small droplets occurs in the 0.5 mM-1 mM range of surfactant concentration and 1% oil to water volume ratio, where the coefficient of friction is also observed to be the least. (C) 2010 Elsevier Inc. All rights reserved.

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The analogy between N-H center dot center dot center dot O and C-H center dot center dot center dot O intermolecular interactions is studied with variable temperature (180-100 K) single crystal X-ray diffraction analysis.5,5-Diethylbarbituric acid (barbital) forms isostructural molecular complexes (co-crystals) with urea (1) and acetamide (2) that respectively contain these analogous interactions.The behaviour of these two interactions as a function of temperature is very similar. This indicates that the C-H center dot center dot center dot O bond in barbital acetamide plays a similar chemical and structural role as does the N-H center dot center dot center dot O bond in barbital urea. The close relationship between these interactions and their comparable nature is further adduced from the formation of a ternary solid solution (3) of barbital, urea and acetamide. The fact that the C-H center dot center dot center dot O interaction in barbital acetamide is weaker than the N-H center dot center dot center dot O interaction in barbital urea is shown by the fact that acetamide is under expressed and urea is over expressed with respect to the quantities of these substances present in solution prior to crystallization of these ternary crystals.

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The dissertation examines how emotional experiences are oriented to in the details of psychotherapeutic interaction. The data (57 audio recorded sessions) come from one therapist-patient dyad in cognitive psychotherapy. Conversation analysis is used as method. The dissertation consists of 4 original articles and a summary. The analyses explicate the therapist s practices of responding to the patient s affective expressions. Different types of affiliating responses are identified. It is shown that the affiliating responses are combined with, or build grounds for, more interpretive and challenging actions. The study also includes a case study of a session with strong misalignment between the therapist s and patient s orientations, showing how this misalignment is managed by the therapist. Moreover, through a longitudinal analysis of the transformation of a sequence type, the study suggests that therapeutic change processes can be located to sequential relations of actions. The practices found in this study are compared to earlier research on everyday talk and on medical encounters. It is suggested that in psychotherapeutic interaction, the generic norms of interaction considering affiliation and epistemic access, are modified for the purposes of therapeutic work. The study also shows that the practices of responding to emotional experience in psychotherapy can deviate from the everyday practices of affiliation. The results of the study are also discussed in terms of concepts arising from clinical theory. These include empathy, validation of emotion, therapeutic alliance, interpretation, challenging beliefs, and therapeutic change. The therapist s approach described in this study involves practical integration of different clinical theories. In general terms, the study suggests that in the details of interaction, psychotherapy recurrently performs a dual task of empathy and challenging in relation to the patient s ways of describing their experiences. Methodologically, the study discusses the problem of identifying actions in conversation analysis of psychotherapy and emotional interaction, and the possibility to apply conversation analysis in the study of therapeutic change.

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It is now well established that the potent anti-microbial compound, triclosan, interrupts the type II fatty acid synthesis by inhibiting the enzyme enoyl-ACP reductase in a number of organisms. Existence of a high degree of similarity between the recently discovered enoyl-ACP reductase from R falciparum and B. napus enzyme permitted building of a satisfactory model for the former enzyme that explained some of the key aspects of the enzyme such as its specificity for binding to the cofactor and the inhibitor. We now report the interaction energies between triclosan and other hydroxydiphenyl ethers with the enzymes from B. napus, E. coli and R falciparum. Examination of the triclosan-enzyme interactions revealed that subtle differences exist in the ligand binding sites of the enzymes from different sources i.e., B. napus, E. coli and P falciparum. A comparison of their binding propensities thus determined should aid in the design of effective inhibitors for the respective enzymes.

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Calreticulin is a lectin-like molecular chaperone of the endoplasmic reticulum in eukaryotes. Its interaction with N-glycosylated polypeptides is mediated by the glycan, Glc(1)Man(9)GlcNAc(2), present on the target glycoproteins. In this work, binding of monoglucosyl IgG (chicken) substrate to calreticulin has been studied using real time association kinetics of the interaction with the biosensor based on surface plasmon resonance (SPR). By SPR, accurate association and dissociation rate constants were determined, and these yielded a micromolar association constant. The nature of reaction was unaffected by immobilization of either of the reactants. The Scatchard analysis values for K-a agreed web crith the one obtained by the ratio k(1)/k(-1). The interaction was completely inhibited by free oligosaccharide, Glc(1)Man(9)GlcNAc(2), whereas Man(9)GlcNAc(2) did not bind to the calreticulin-substrate complex, attesting to the exquisite specificity of this interaction. The binding of calreticulin to IgG was used for the development of immunoassay and the relative affinity of the lectin-substrate association was indirectly measured. The values are in agreement with those obtained with SPR. Although the reactions are several orders of magnitude slower than the diffusion controlled processes, the data are qualitatively and quantitatively consistent with single-step bimolecular association and dissociation reaction. Analyses of the activation parameters indicate that reaction is enthalpically driven and does not involve a highly ordered transition state. Based on these data, the mechanism of its chaperone activity is briefly discussed.

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Lectins (phytohaemagglutinin) are known to have the unique property of binding with certain specific sugars, polysaccharides and glycoproteins. Although the kinetics of interaction between lectins and sugar have been extensively studied, the binding characteristics of the lectins with various glycoproteins are not well understood. In this laboratory a systematic study has been initiated in relation to the interaction of lectins with glycoproteins. Concanavalin A is known to bind alpha-glucosides, mannosides and biopolymers having these sugar configurations. A galactose binding protein from caster bean has been purified to homogeneity and was found to contain mannose. This lectin was used as the source of glycoprotein for studying its interaction with concanavalin A. This study showed that the interaction is temperature dependent and the dissociation is time and alpha-methyl glucoside concentration dependent. This has led to speculate a model for cell-lectin interaction. Using concanavalin A it has been shown that all the lysosomal enzymes from brain studied were glycoprotein in nature. Moreover, using Sepharose-bound concanavalin A it has been possible to devise a method by which these lysosomal enzymes could be purified considerably. With the knowledge that the interaction between lectin and glycoprotein is not only dependent on the specific sugar present in the glycoprotein, but also on the nature of the glycoprotein it was possible to develop a novel method for immobilizing various glycoprotein enzymes, such as arylsulphatase A, hyaluronidase and glucose oxidase.

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We report new radio continuum and 21 cm HI observations using the Giant Metrewave Radio Telescope (GMRT) of the group Holmberg 124 ( Ho 124) comprising four late-type galaxies, namely NGC 2820, Mrk 108, NGC 2814 and NGC 2805. The three galaxies, NGC 2820, Mrk 108 and NGC 2814 which are closely located in the sky plane have clearly undergone tidal interactions as seen from the various morphological tidal signatures and debris. Moreover we note various features in the group members which we believe might be due to ram pressure. In this paper, we describe four interesting results emerging from our observations: a) detection of the tidal radio continuum bridge at 330 MHz connecting the galaxies NGC 2820+ Mrk 108 with NGC 2814. The radio bridge was discovered at 1465 MHz by van der Hulst & Hummel ( 1985, A& A, 150, 17). We find that the bridge has a fairly steep spectrum with a spectral index alpha(S proportional to nu(alpha)) of - 1.8(-0.2)(+0.3) which is much steeper than the - 0.8 quoted by van der Hulst & Hummel ( 1985); b) detection of other tidal features like the tilted HI and radio continuum disk of NGC 2814, a HI streamer and a radio continuum tail arising from the south of NGC 2814. We also report the detection of a possible tidal dwarf galaxy in HI; c) sharp truncation in the HI distribution in the south of NGC 2820 and in the HI and radio continuum distribution in the north of NGC 2814. The optical disks in both the cases look undisturbed. As pointed out by Davis et al. ( 1997, AJ, 114, 613), ram pressure affects different components of the interstellar medium to varying degrees. Simple estimates of pressure in different components of the interstellar medium ( radio continuum, Ha and HI) in NGC 2820 indicate that ram pressure will significantly influence HI; d) detection of a large one-sided HI loop to the north of NGC 2820. No radio continuum emission or Ha emission is associated with the HI loop. We discuss various scenarios for the origin of this loop including a central starburst, ram pressure stripping and tidal interaction. We do not support the central starburst scenario since the loop is not detected in ionized gas. Using the upper limit on X-ray luminosity of Ho 124 (Mulchaey et al. 2003, ApJS, 145, 39), we estimate an upper limit on the intragroup medium (IGrM) density of 8.8 x 10(-4) cm(-3). For half this electron density, we estimate the ram pressure force of the IGrM to be comparable to the gravitational pull of the disk of NGC 2820. Since tidal interaction has obviously influenced the group, we suggest that the loop could have formed by ram pressure stripping if tidal effects had reduced the surface density of HI in NGC 2820. From the complex observational picture of Ho 124 and the numerical estimates, we suggest that the evolution of the Ho 124 group may be governed by both tidal forces due to the interaction and the ram pressure due to motion of the member galaxies in the IGrM and that the IGrM densities should not be too low (i.e. >= 4 x 10(-4)). However this needs to be verified by further observations.