818 research outputs found

    Stability of the Malvinas Current

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    Deterministic and probabilistic tools from nonlinear dynamics are used to assess enduring near-surface Lagrangian aspects of the Malvinas Current. The deterministic tools are applied on a multi-year record of velocities derived from satellite altimetry data, revealing a resilient cross-stream transport barrier. This is composed of shearless-parabolic Lagrangian coherent structures (LCS), which, extracted over sliding time windows along the multi-year altimetry-derived velocity record, lie in near coincidental position. The probabilistic tools are applied on a large collection of historical satellite-tracked drifter trajectories, revealing weakly communicating flow regions on either side of the altimetry-derived barrier. Shearless-parabolic LCS are detected for the first time from altimetry data, and their significance is supported on satellite-derived ocean color data, which reveal shapes that quite closely resemble the peculiar V shapes, dubbed `chevrons,' that have recently confirmed the presence of similar LCS in the atmosphere of Jupiter. Finally, using in-situ velocity and hydrographic data, conditions for symmetric stability are found to be satisfied, suggesting a duality between Lagrangian and Eulerian stability for the Malvinas Current.Comment: Submitted to Scientific Report

    Parallel Online Time Warping for Real-Time Audio-to-Score Alignment in Multi-core Systems

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    [EN] The Audio-to-Score framework consists of two separate stages: pre- processing and alignment. The alignment is commonly solved through offline Dynamic Time Warping (DTW), which is a method to find the path over the distortion matrix with the minimum cost to determine the relation between the performance and the musical score times. In this work we propose a par- allel online DTW solution based on a client-server architecture. The current version of the application has been implemented for multi-core architectures (x86, x64 and ARM), thus covering either powerful systems or mobile devices. An extensive experimentation has been conducted in order to validate the software. The experiments also show that our framework allows to achieve a good score alignment within the real-time window by using parallel computing techniques.This work has been partially supported by Spanish Ministry of Science and Innovation and FEDER under Projects TEC2012-38142-C04-01, TEC2012-38142-C04-03, TEC2012-38142-C04-04, TEC2015-67387-C4-1-R, TEC2015-67387-C4-3-R, TEC2015-67387-C4-4-R, the European Union FEDER (CAPAP-H5 network TIN2014-53522-REDT), and the Generalitat Valenciana under Grant PROMETEOII/2014/003.Alonso-JordĂĄ, P.; Cortina, R.; RodrĂ­guez-Serrano, F.; Vera-Candeas, P.; Alonso-GonzĂĄlez, M.; Ranilla, J. (2017). Parallel Online Time Warping for Real-Time Audio-to-Score Alignment in Multi-core Systems. The Journal of Supercomputing. 73(1):126-138. https://doi.org/10.1007/s11227-016-1647-5S126138731Joder C, Essid S, Richard G (2011) A conditional random field framework for robust and scalable audio-to-score matching. IEEE Trans Speech Audio Lang Process 19(8):2385–2397McNab RJ, Smith LA, Witten IH, Henderson CL, Cunningham SJ (1996) Towards the digital music library: tune retrieval from acoustic input. In: DL 96: Proceedings of the first ACM international conference on digital libraries. ACM, New York, pp 11–18Dannenberg RB (2007) An intelligent multi-track audio editor. In: Proceedings of international computer music conference (ICMC), vol 2, pp 89–94Duan Z, Pardo B (2011) Soundprism: an online system for score-informed source separation of music audio. IEEE J Sel Topics Signal Process 5(6):1205–1215Dixon S (2005) Live tracking of musical performances using on-line time warping. In: Proceedings of the international conference on digital audio effects (DAFx), Madrid, Spain, pp 92–97Orio N, Schwarz D (2001) Alignment of monophonic and polyphonic music to a score. In: Proceedings of the international computer music conference (ICMC), pp 129–132Simon I, Morris D, Basu S (2008) MySong: automatic accompaniment generation for vocal melodies. In: Proceedings of the SIGCHI conference on human factors in computing systems. ACM, New York, pp 725–734Rodriguez-Serrano FJ, Duan Z, Vera-Candeas P, Pardo B, Carabias-Orti JJ (2015) Online score-informed source separation with adaptive instrument models. J New Music Res Lond 44(2):83–96Arzt A, Widmer G, Dixon S (2008) Automatic page turning for musicians via real-time machine listening. In: Proceedings of the 18th European conference on artificial intelligence. IOS Press, Amsterdam, pp 241–245Carabias-Orti JJ, Rodriguez-Serrano FJ, Vera-Candeas P, Canadas-Quesada FJ, Ruiz-Reyes N (2015) An audio to score alignment framework using spectral factorization and dynamic time warping. In: 16th International Society for music information retrieval conference, pp 742–748RodrĂ­guez-Serrano FJ, MenĂ©ndez-Canal J, Vidal A, Cañadas-Quesada FJ, Cortina R (2015) A DTW based score following method for score-informed sound source separation. In: Proceedings of the 12th sound and music computing conference 2015 (SMC-15), Ireland, pp 491–496Carabias-OrtĂ­ JJ, RodrĂ­guez-Serrano FJ, Vera-Candeas P, Cañadas-Quesada FJ, RuĂ­z-Reyes N (2013) Constrained non-negative sparse coding using learnt instrument templates for realtime music transcription. Eng Appl Artif Intell 26(7):1671–1680Raphael C (2006) Aligning music audio with symbolic scores using a hybrid graphical model. Mach Learn 65:389–409Schreck-Ensemble (2001–2004) ComParser 1.42. http://home.hku.nl/~pieter.suurmond/SOFT/CMP/doc/cmp.html . Accessed Sept 2015Itakura F (1975) Minimum prediction residual principle applied to speech recognition. IEEE Trans Acoust Speech Signal Process 23:52–72Dannenberg R, Hu N (2003) Polyphonic audio matching for score following and intelligent audio editors. In: Proceedings of the international computer music conference. International Computer Music Association, San Francisco, pp 27–34Mueller M, Kurth F, Roeder T (2004) Towards an efficient algorithm for automatic score-to-audio synchronization. In: Proceedings of the 5th international conference on music information retrieval, Barcelona, SpainMueller M, Mattes H, Kurth F (2006) An efficient multiscale approach to audio synchronization. In: Proceedings of the 7th international conference on music information retrieval, Victoria, CanadaKaprykowsky H, Rodet X (2006) Globally optimal short-time dynamic time warping applications to score to audio alignment. In: IEEE ICASSP, Toulouse, France, pp 249–252Fremerey C, MĂŒller M, Clausen M (2010) Handling repeats and jumps in score-performance synchronization. In: Proceedings of ISMIR, pp 243–248Arzt A, Widmer G (2010) Towards effective any-time music tracking. In: Proceedings of starting AI researchers symposium (STAIRS), Lisbon, Portugal, pp 24–3

    Assessment of potential cardiotoxic side effects of mitoxantrone in patients with multiple sclerosis

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    Previous studies showed that mitoxantrone can reduce disability progression in patients with multiple sclerosis (MS). There is, however, concern that it may cause irreversible cardiomyopathy with reduced left ventricular (LV) ejection fraction (EF) and congestive heart failure. The aim of this prospective study was to investigate cardiac side effects of mitoxantrone by repetitive cardiac monitoring in MS patients. The treatment protocol called for ten courses of a combined mitoxantrone (10 mg/m(2) body surface) and methylprednisolone therapy. Before each course, a transthoracic echocardiogram was performed to determine the LV end-diastolic diameter, the end-systolic diameter and the fractional shortening; the LV-EF was calculated. Seventy-three patients participated (32 males; age 48 +/- 12 years, range 20-75 years; 25 with primary progressive, 47 with secondary progressive and 1 with relapsing-remitting MS) who received at least four courses of mitoxantrone. Three of the 73 patients were excluded during the study (2 patients discontinued therapy; 1 patient with a previous history of ischemic heart disease developed atrial fibrillation after the second course of mitoxantrone). The mean cumulative dose of mitoxantrone was 114.0 +/- 33.8 mg. The mean follow-up time was 23.4 months (range 10-57 months). So far, there has been no significant change in any of the determined parameters (end-diastolic diameter, end-systolic diameter, fractional shortening, EF) over time during all follow-up investigations. Mitoxantrone did not cause signs of congestive heart failure in any of the patients. Further cardiac monitoring is, however, needed to determine the safety of mitoxantrone after longer follow-up times and at higher cumulative doses. Copyright (C) 2005 S. Karger AG, Basel

    Bacterial porin disrupts mitochondrial membrane potential and sensitizes host cells to apoptosis

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    The bacterial PorB porin, an ATP-binding beta-barrel protein of pathogenic Neisseria gonorrhoeae, triggers host cell apoptosis by an unknown mechanism. PorB is targeted to and imported by host cell mitochondria, causing the breakdown of the mitochondrial membrane potential (delta psi m). Here, we show that PorB induces the condensation of the mitochondrial matrix and the loss of cristae structures, sensitizing cells to the induction of apoptosis via signaling pathways activated by BH3-only proteins. PorB is imported into mitochondria through the general translocase TOM but, unexpectedly, is not recognized by the SAM sorting machinery, usually required for the assembly of beta-barrel proteins in the mitochondrial outer membrane. PorB integrates into the mitochondrial inner membrane, leading to the breakdown of delta psi m. The PorB channel is regulated by nucleotides and an isogenic PorB mutant defective in ATP-binding failed to induce delta psi m loss and apoptosis, demonstrating that dissipation of delta psi m is a requirement for cell death caused by neisserial infection

    Real-time Soundprism

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    [EN] This paper presents a parallel real-time sound source separation system for decomposing an audio signal captured with a single microphone in so many audio signals as the number of instruments that are really playing. This approach is usually known as Soundprism. The application scenario of the system is for a concert hall in which users, instead of listening to the mixed audio, want to receive the audio of just an instrument, focusing on a particular performance. The challenge is even greater since we are interested in a real-time system on handheld devices, i.e., devices characterized by both low power consumption and mobility. The results presented show that it is possible to obtain real-time results in the tested scenarios using an ARM processor aided by a GPU, when this one is present.This work has been supported by the "Ministerio de Economia y Competitividad" of Spain and FEDER under projects TEC2015-67387-C4-{1,2,3}-R.Muñoz-Montoro, AJ.; Ranilla, J.; Vera-Candeas, P.; Combarro, EF.; Alonso-JordĂĄ, P. (2019). Real-time Soundprism. The Journal of Supercomputing. 75(3):1594-1609. https://doi.org/10.1007/s11227-018-2703-0S15941609753Alonso P, Cortina R, RodrĂ­guez-Serrano FJ, Vera-Candeas P, Alonso-GonzĂĄlez M, Ranilla J (2017) Parallel online time warping for real-time audio-to-score alignment in multi-core systems. J Supercomput 73:126. https://doi.org/10.1007/s11227-016-1647-5Carabias-Orti JJ, Cobos M, Vera-Candeas P, RodrĂ­guez-Serrano FJ (2013) Nonnegative signal factorization with learnt instrument models for sound source separation in close-microphone recordings. EURASIP J Adv Signal Process 2013:184. https://doi.org/10.1186/1687-6180-2013-184Carabias-Orti JJ, Rodriguez-Serrano FJ, Vera-Candeas P, Canadas-Quesada FJ, Ruiz-Reyes N (2015) An audio to score alignment framework using spectral factorization and dynamic time warping. In: 16th International Society for Music Information Retrieval Conference, pp 742–748DĂ­az-Gracia N, Cocaña-FernĂĄndez A, Alonso-GonzĂĄlez M, MartĂ­nez-ZaldĂ­var FJ, Cortina R, GarcĂ­a-MollĂĄ VM, Alonso P, Ranilla J (2014) NNMFPACK: a versatile approach to an NNMF parallel library. In: Proceedings of the 2014 International Conference on Computational and Mathematical Methods in Science and Engineering, pp 456–465DĂ­az-Gracia N, Cocaña-FernĂĄndez A, Alonso-GonzĂĄlez M, MartĂ­nez-ZaldĂ­var FJ, Cortina R, GarcĂ­a-MollĂĄ VM, Vidal AM (2015) Improving NNMFPACK with heterogeneous and efficient kernels for ÎČ\beta ÎČ -divergence metrics. J Supercomput 71:1846–1856. https://doi.org/10.1007/s11227-014-1363-yDriedger J, Grohganz H, PrĂ€tzlich T, Ewert S, MĂŒller M (2013) Score-informed audio decomposition and applications. In: Proceedings of the 21st ACM International Conference on Multimedia, pp 541–544Duan Z, Pardo B (2011) Soundprism: an online system for score-informed source separation of music audio. IEEE J Sel Top Signal Process 5(6):1205–1215Duong NQ, Vincent E, Gribonval R (2010) Under-determined reverberant audio source separation using a full-rank spatial covariance model. IEEE Trans Audio Speech 18(7):1830–1840. https://doi.org/10.1109/TASL.2010.2050716Ewert S, MĂŒller M (2011) Estimating note intensities in music recordings. In: Proceedings of the IEEE International Conference on Acoustics, Speech, and Signal Processing, pp 385–388Ewert S, Pardo B, Mueller M, Plumbley MD (2014) Score-informed source separation for musical audio recordings: an overview. IEEE Signal Process Mag 31:116–124. https://doi.org/10.1109/MSP.2013.2296076Fastl H, Zwicker E (2007) Psychoacoustics. Springer, BerlinGanseman J, Scheunders P, Mysore GJ, Abel JS (2010) Source separation by score synthesis. Int Comput Music Conf 2010:1–4Goto M, Hashiguchi H, Nishimura T, Oka R (2002) RWC music database: popular, classical and jazz music databases. In: ISMIR, vol 2, pp 287–288Goto M (2004) Development of the RWC music database. In: Proceedings of the 18th International Congress on Acoustics (ICA 2004), ppp 553–556Hennequin R, David B, Badeau R (2011) Score informed audio source separation using a parametric model of non-negative spectrogram. In: 2011 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) pp 45–48. https://doi.org/10.1109/ICASSP.2011.5946324Itoyama K, Goto M, Komatani K et al (2008) Instrument equalizer for query-by-example retrieval: improving sound source separation based on integrated harmonic and inharmonic models. In: ISMIR. https://doi.org/10.1136/bmj.324.7341.827Marxer R, Janer J, Bonada J (2012) Low-latency instrument separation in polyphonic audio using timbre models. In: International Conference on Latent Variable Analysis and Signal Separation, pp 314–321Miron M, Carabias-Orti JJ, Janer J (2015) Improving score-informed source separation for classical music through note refinement. In: ISMIR, pp 448–454Ozerov A, FĂ©votte C (2010) Multichannel nonnegative matrix factorization in convolutive mixtures for audio source separation. IEEE Trans Audio Speech Lang Process 18:550–563. https://doi.org/10.1109/TASL.2009.2031510Ozerov A, Vincent E, Bimbot F (2012) A general flexible framework for the handling of prior information in audio source separation. IEEE Trans Audio Speech Lang Process 20:1118–1133. https://doi.org/10.1109/TASL.2011.2172425PĂ€tynen J, Pulkki V, Lokki T (2008) Anechoic recording system for symphony orchestra. 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    Current challenges of research on filamentous fungi in relation to human welfare and a sustainable bio-economy: a white paper.

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    The EUROFUNG network is a virtual centre of multidisciplinary expertise in the field of fungal biotechnology. The first academic-industry Think Tank was hosted by EUROFUNG to summarise the state of the art and future challenges in fungal biology and biotechnology in the coming decade. Currently, fungal cell factories are important for bulk manufacturing of organic acids, proteins, enzymes, secondary metabolites and active pharmaceutical ingredients in white and red biotechnology. In contrast, fungal pathogens of humans kill more people than malaria or tuberculosis. Fungi are significantly impacting on global food security, damaging global crop production, causing disease in domesticated animals, and spoiling an estimated 10 % of harvested crops. A number of challenges now need to be addressed to improve our strategies to control fungal pathogenicity and to optimise the use of fungi as sources for novel compounds and as cell factories for large scale manufacture of bio-based products. This white paper reports on the discussions of the Think Tank meeting and the suggestions made for moving fungal bio(techno)logy forward

    Improvisation and Transformation: Yes to the Mess

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    The field of organizational change has chiefly been studied from a teleological perspective. Most models of change emphasize action that is rational and goal oriented. What often gets overlooked and under theorized is the continuous, iterative nature of organizational life, the unplanned and serendipitous actions by and between people that lead to new discoveries and innovation. Recent research on organizational improvisation seeks to explore this area. In this chapter we will address two questions – what is the experience of improvisation and what are the conditions that support improvisation to flourish in organizations? In the first part of this paper, we look at the phenomenology of improvisation, the actual lived experience of those who improvise in the face of the unknown or in the midst of chaotic conditions. We will explore the strategies that some professional improvisers employ to deliberately create the improvisatory moment. We will then look at the dynamics of organizational life and explore the cultural beliefs, organizational structures, and leadership practices that support improvisation. We will draw primarily upon the model from Barrett (2012) that focuses on the how the nature of jazz improvisation and the factors that support improvisation can be transferred to leadership activities. This falls in the tradition of others who draw upon arts-based metaphors, including jazz music and theatrical improvisation, to suggest insights for leadership and ways of organizing. Since this is a book devoted to individual transformation as well as organizational transformation, we will also touch on the topic of how improvisation is a developmental project and explore the potential for improvisation to lead to personal transformation. We will attempt to move back and forth between both themes – organizational and personal transformation. Ultimately the two topics are not separate. Any significant organizational transformation begins with an improvisation. And any meaningful improvisatory move by a person is potentially a moment of self-discovery and an identity-shaping event

    SEND: a system for electronic notification and documentation of vital sign observations

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    Background: Recognising the limitations of a paper-based approach to documenting vital sign observations and responding to national clinical guidelines, we have explored the use of an electronic solution that could improve the quality and safety of patient care. We have developed a system for recording vital sign observations at the bedside, automatically calculating an Early Warning Score, and saving data such that it is accessible to all relevant clinicians within a hospital trust. We have studied current clinical practice of using paper observation charts, and attempted to streamline the process. We describe our user-focussed design process, and present the key design decisions prior to describing the system in greater detail. Results: The system has been deployed in three pilot clinical areas over a period of 9 months. During this time, vital sign observations were recorded electronically using our system. Analysis of the number of observations recorded (21,316 observations) and the number of active users (111 users) confirmed that the system is being used for routine clinical observations. Feedback from clinical end-users was collected to assess user acceptance of the system. This resulted in a System Usability Scale score of 77.8, indicating high user acceptability. Conclusions: Our system has been successfully piloted, and is in the process of full implementation throughout adult inpatient clinical areas in the Oxford University Hospitals. Whilst our results demonstrate qualitative acceptance of the system, its quantitative effect on clinical care is yet to be evaluated
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