108 research outputs found

    A comparative study of measured amplitude and phase perturbations of VLF and LF radio signals induced by solar flares

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    Very Low Frequency, VLF and Low Frequency, LF signal perturbations were examined to study ionospheric disturbances induced by solar X-ray flares. The aim was to understand processes in propagation VLF/LF radio signals over short paths, and to estimate specific characteristics of each short path. The receiver at Belgrade station continuously monitor the amplitude and phase of coherent and subionospherically propagating LF signal operated in Sicily, NSC at 45.90, kHz and VLF signal operated in Isola di Tavolara ICV at 20.27 kHz, with great circle distances of 953 km and 976 km, respectively. Geographical locations of transmitters and receiver site result that these short paths have many similarity. The main difference is in transmitter frequencies. In period from 2008 to February 2014 were selected around 200 events for further examination. In all selected examples amplitude and phase on VLF and LF signals were perturbed by occurrence of solar X-ray flares. This six years period covers minimum and maximum of solar activity. Also, simultaneous measurement of amplitude and phase on the VLF/LF signals during occurrence of solar flare were employed for constructing electron density profile versus altitude and also in a function of time over middle Europe.Comment: published in Serb.Astron.

    Cyvers city: poetry and practice

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    El presente artículo justamente reflexiona en torno a la obra denominada Cyvers City, cuya intención por combinar la poïesis con la técnica, la ubica en los ámbitos de las profundas preguntas que se han hecho en la estética occidental desde la misma separación que los artistas realizaran de la producción artesanal. La vinculación con la ciencia que ha perseguido el arte desde el Renacimiento, encuentra en proyectos como Cyvers uno de los caminos, que propuestos desde la autora, propenden por transformar nuestra percepción e idea del mundo.Abstract: This article reflects on the work called Cyvers City whose intention to combine pioesis with technique, locates it in the area of deep questions that have been asked in the western aesthetics from the separation artists made of handcrafted production. The connection with science that art has been pursuing since the Renaissance finds in projects such as Cyvers one of the ways that, proposed from the author, tend for the transformation of our perception and idea of the world

    Cyvers city: poetry and practice

    Get PDF
    Abstract: This article reflects on the work called Cyvers City whose intention to combine pioesis with technique, locates it in the area of deep questions that have been asked in the western aesthetics from the separation artists made of handcrafted production. The connection with science that art has been pursuing since the Renaissance finds in projects such as Cyvers one of the ways that, proposed from the author, tend for the transformation of our perception and idea of the world

    Embedded antenna technology in smart polymeric composite structures

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    One of the fastest-growing uses of sheet moulding compound (SMC) material is in the area of manufacturing of vehicle body components for both structural and non-structural applications. This trend is accelerating, driven by original equipment manufacturers (OEM) and their need for lighter and more fuel-efficient vehicles. In addition, over the last 20 years, the number of entertainment and communication systems in vehicles has also been expanding. The aim of this research is the development of a single wideband antenna that is capable of receiving all of the major services of interest. Taking this approach one step further and embedding such an antenna in a polymeric composite vehicle body panel would combine the benefits of reduced coefficient of drag, lower vehicle weight, reduced assembly complexity and shorter assembly time. These benefits would manifest themselves in the form of lower overall design and manufacturing vehicle cost for the OEMs and lower fuel consumption for customers. This thesis will deal with the development of such an antenna and the challenges faced in embedding it in a polymeric composite vehicle panel to such an extent that it becomes a seamless part of the vehicle body. This application required the development of a detailed understanding of the following three areas. Firstly, understanding of the interactions and effects of SMC material and automotive paint on antenna signal quality and performance through experiments and electromagnetic modelling (EM). Secondly, the development of the manufacturing process and material used to embed the antenna and its impact on the physical properties of the antenna through rheological testing, analytical modelling and experimentation. Lastly, the development of a wideband antenna capable of receiving pre-determined signals, through EM and field testing. The effects of paint application and presence of SMC resulted in a frequency shift of less than 1%. The experiments correlated well with the analytical model developed for compression moulding which incorporates a novel inclusion of the Maxwell’s model to predict the shear forces in the material flow within a confined space. A modular planar inverted conical antenna (PICA) was developed and optimised for the frequency range 700MHz – 9000MHz, which includes the commercial global positioning system (GPS) frequency. This development was then deployed as an embedded prototype in the deck lid of a test vehicle. Comparison against commercial GPS and mobile phone antennas was undertaken. This field test comparison showed that the developed PICA antenna performed better than the commercial antenna by up to 17%, especially in spaces devoid of multi-path signals

    Identification of tissue transglutaminase protein network

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    2009/2010Tissue transglutaminase (TG2) is a multifunctional enyzme involved in cell growth and differentiantion, receptor mediated endocytosis, cell adhesion and morphology, stabilization of extracellular matrix, membrane trafficking and structure/function, signal transduction, regulation of cytoskeleton and apoptosis. Multiple lines of evidence suggest an involvement of TG2 autoimmune diseases, cancer and in neurodegenerative diseases, including Alzheimer's disease, progressive supranuclear palsy, Huntington's disease and Parkinson's disease. In all of the neurodegenerative diseases examined to date, TG2 activity is upregulated in selectively vulnerable brain regions, TG2 proteins are associated with inclusion bodies characteristic of the diseases, and prominent proteins in the inclusion bodies are modified by TG2 enzyme. It is important to identify TG2 substrates as they may offer an understanding of how the TG2-catalyzed post-translational modification has an impact on physiology and disease. Identification of these substrates may lead to novel drug targets and new diagnostic markers for several TG2-related diseases. A variety of different methods have been proposed for the identification of TG2 substrates. In this work we applied a new method for identification of TG2 substrates (interactors) by using a selection of cDNA phage display libraries followed by massive gene sequencing with 454 system. Ranking and analysis of more than 120,000 sequences allowed us to identify several potential substrates and interactors, which were subsequently confirmed in functional assays. Within the identified clones, some had been previously described as interacting proteins (fibronectin, SMOC1, EIF4G2, MYO18A, GSTO2), while others were new. When compared to standard systems, such as microtiter ELISA, the method described here is dramatically faster and yields far more information about the interaction under study, allowing better characterization of complex systems. For example, in the case of fibronectin, it was possible to identify the specific domains involved in the interaction. We expect that this approach to library and selection analysis can also be extended to other methods traditionally used to study protein-protein interactions, as well as to the study of the selection of peptides and antibodies by phage display.L'enzima transglutaminasi tissutale è un enzima multifunzionale. Questa proteina gioca un ruolo importante durante lo sviluppo, crescita e differenziamento cellulare, endocitosi mediata da recettore, adesione e morfologia cellulare, stabilizzazione della matrice extracellulare, traffico e struttura/funzione di membrana, trasduzione del segnale, regolazione del citoscheletro ed apoptosi. Molteplici evidenze indicano un coinvolgimento di TG2 in diverse patologie neurodegenerative, incluso il morbo di Alzheimer, la paralisi progressiva supranucleare, il morbo di Huntington e quello di Parkinson. In tutte le malattie neurodegenerative esaminate finora, l'attività della TG2 è aumentata in specifiche regioni cerebrali e le proteine sono associate in corpi d’inclusione caratteristici di tali patologie dove vengono modificate dall'enzima TG2. E’ importante identificare i substrati della TG2 per comprendere come le modifiche post-traduzionali introdotte da questo enzima siano coinvolte nella patogenesi delle suddette malattie. Molteplici metodiche sperimentali sono state proposte ai fini dell'identificazione dei substrati della TG2. In questo lavoro è stato applicato un nuovo metodo per l’identificazione dei substrati della TG2 (interattori), selezionando una libreria di cDNA espressa come phage display, seguito da un sequenziamento genico massivo utilizzando il sistema 454 Life Sciences. La classificazione e l’analisi di più di 120,000 sequenze di DNA ha permesso di identificare molti substrati e potenziali interattori, che sono stati successivamente confermati con le analisi funzionali. All’interno dei cloni identificati, alcuni erano già stati precedentemente descritti come proteine interagenti (interattori) (fibronectina, SMOC1, EIF4G1, MYO18A, GSTO2), mentre altri sono stati identificati come nuovi. Nella comparazione con i metodi standard, come, ad esempio, ELISA, il metodo qui descritto risulta enormemente più rapido e fornisce un numero molto maggiore di informazioni relative alle interazioni analizzate, permettendo quindi una migliore caratterizzazione di sistemi complessi. Ad esempio, nel caso della fibronectina, è stato possibile identificare i domini specifici coinvolti nell’interazione. Prevediamo che questo approccio per l’analisi e la selezione di librerie, possa essere applicato anche ad altri metodi tradizionalmente usati per lo studio di interazioni proteina- proteina, così come allo studio di selezioni di peptidi e anticorpi tramite la tecnica del phage display.XXIII Ciclo197
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