989 research outputs found
Numerical Quantum Field Theory on the Continuum and a New Look at Perturbation Theory
The Source Galerkin method finds approximate solutions to the functional
differential equations of field theories in the presence of external sources.
While developing this process, it was recognized that approximations of the
spectral representations of the Green's functions by Sinc function expansions
are an extremely powerful calculative tool. Specifically, this understanding
makes it not only possible to apply the Source Galerkin method to higher
dimensional field theories, but also leads to a new approach to perturbation
theory calculations in scalar and fermionic field theories. This report
summarizes the methodologies for solving quantum field theories with the Source
Galerkin method and for performing perturbation theory calculations using Sinc
approximations.Comment: Lattice2001(theorydevelop
The mathematical stability study for the system of the CoO(OH) – overoxidized polypyrrole composite synthesis in the presence of fluor ions
The potentiostatic synthesis of CoO(OH) – Overoxidized polypyrrole composite in the presence of fluor ions has been investigated mathematically. The corresponding mathematical model was described and analyzed by means of linear stability theory and bifurcation analysis. The steady-state stability requirements, like also oscillatory and monotonic instability conditions are derived.Mongolian Journal of Chemistry 16 (42), 2015, 13-1
The global build-up to intrinsic ELM bursts and comparison with pellet triggered ELMs seen in JET
We focus on JET plasmas in which ELMs are triggered by pellets in the presence of ELMs
which occur naturally. We perform direct time domain analysis of signals from fast radial
field coils and toroidal full flux azimuthal loops. These toroidally integrating signals provide
simultaneous high time resolution measurements of global plasma dynamics and its coupling
to the control system. We examine the time dynamics of these signals in plasmas where pellet
injection is used to trigger ELMs in the presence of naturally occurring ELMs. Pellets whose
size and speed are intended to provide maximum local perturbation for ELM triggering are
launched at pre-programmed times, without correlation to the occurrence times of intrinsic
ELMs. Pellet rates were sufficiently low to prevent sustained changes of the underlying
plasma conditions and natural ELM behaviour. We find a global signature of the build-up to
natural ELMs in the temporal analytic phase of both the full flux loops and fast radial field
coil signals. Before a natural ELM, the signal phases align to the same value on a ∼2–5ms
timescale. This global build up to a natural ELM occurs whilst the amplitude of the full flux
loop and fast radial field coil signals are at their background value: it precedes the response
seen in these signals to the onset of ELMing. In contrast these signals do not clearly phase
align before the ELM for ELMs which are the first to occur following pellet injection. This
provides a direct test that can distinguish when an ELM is triggered by a pellet as opposed to
occurring naturally. It further supports the idea [1–4] of a global build up phase that precedes
natural ELMs; pellets can trigger ELMs even when the signal phase is at a value when a
natural ELM is unlikely to occurEURATOM 633053ONR NICOP N62909-15-1-N14
Damage Spreading During Domain Growth
We study damage spreading in models of two-dimensional systems undergoing
first order phase transitions. We consider several models from the same
non-conserved order parameter universality class, and find unexpected
differences between them. An exact solution of the Ohta-Jasnow-Kawasaki model
yields the damage growth law , where in
dimensions. In contrast, time-dependent Ginzburg-Landau simulations and Ising
simulations in using heat-bath dynamics show power-law growth, but with
an exponent of approximately , independent of the system sizes studied.
In marked contrast, Metropolis dynamics shows damage growing via , although the damage difference grows as . PACS: 64.60.-i, 05.50.+qComment: 4 pags of revtex3 + 3 postscript files appended as a compressed and
uuencoded file. UIB940320
Strategies and Techniques for Use and Exploitation of Contextual Information in High-Level Fusion Architectures
Proceedings of: 13th Conference on Information Fusion (FUSION 2010): Edinburgh, UK. 26-29 July 2010.Contextual Information is proving to be not only an additional exploitable information source for improving entity and situational estimates in certain Information Fusion systems, but can also be the entire focus of estimation for such systems as those directed to Ambient Intelligence (AI) and Context-Aware(CA) applications. This paper will discuss the role(s) of Contextual Information (CI) in a wide variety of IF applications to include AI, CA, Defense, and Cyber-security among possible others, the issues involved in designing strategies and techniques for CI use and exploitation, provide some exemplars of evolving CI use/exploitation designs on our current projects, and describe some general frameworks that are evolving in various application domains where CI is proving critical.The UC3M Team gratefully acknowledge that this
research activity is supported in part by Projects CICYT
TIN2008-06742-C02-02/TSI, CICYT TEC2008-06732-
C02-02/TEC, CAM CONTEXTS (S2009/TIC-1485) and
DPS2008-07029-C02-02.
UC3M also thanks Prof. James Llinas for his helpful
comments during his stay, which has been supported by
the collaboration agreement ‘Chairs of Excellence’
between University Carlos III and Banco Santander.
The US/UB Team gratefully acknowledge that this
research activity is supported by a Multidisciplinary
University Research Initiative (MURI) grant (Number
W911NF-09-1-0392) for “Unified Research on Networkbased
Hard/Soft Information Fusion”, issued by the US
Army Research Office (ARO) under the program
management of Dr. John LaveryPublicad
Mechanical control of nuclear import by Importin-7 is regulated by its dominant cargo YAP
Mechanical forces regulate multiple essential pathways in the cell. The nuclear translocation of mechanoresponsive transcriptional regulators is an essential step for mechanotransduction. However, how mechanical forces regulate the nuclear import process is not understood. Here, we identify a highly mechanoresponsive nuclear transport receptor (NTR), Importin-7 (Imp7), that drives the nuclear import of YAP, a key regulator of mechanotransduction pathways. Unexpectedly, YAP governs the mechanoresponse of Imp7 by forming a YAP/Imp7 complex that responds to mechanical cues through the Hippo kinases MST1/2. Furthermore, YAP behaves as a dominant cargo of Imp7, restricting the Imp7 binding and the nuclear translocation of other Imp7 cargoes such as Smad3 and Erk2. Thus, the nuclear import process is an additional regulatory layer indirectly regulated by mechanical cues, which activate a preferential Imp7 cargo, YAP, which competes out other cargoes, resulting in signaling crosstalk.We thank Miguel Sánchez for text editing. We thank Erika R. Geisbrecht, Kenneth Irvine, and Ariberto Fassati for kindly providing reagents. This study was supported by grants from the Spanish Ministry of Science and Innovation (MICIIN)/Agencia Estatal de Investigación (AEI)/European Regional Development Fund (ARDF/FEDER) “A way to make Europe” (PID2020-118658RB-I00, SAF2017-83130-R, IGP-SO grant MINSEV1512-07-2016, CSD2009-0016 and BFU2016-81912-REDC), Comunidad Autónoma de Madrid (Tec4Bio-CM, S2018/NMT¬4443), Fundació La Marató de TV3 (201936-30-31), “La Caixa” Foundation (HR20-00075) and AECC (PROYE20089DELP) all to M.A.d.P. This project has received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No. 641639. M.G.G. and L.S. are sponsored by FPU fellowships (FPU15/03776 and FPU18/05394, respectively). The CNIC is supported by the Instituto de Salud Carlos III (ISCIII), the Ministerio de Ciencia e Innovación (MICIIN) and the Pro CNIC Foundation, and is a Severo Ochoa Center of Excellence CEX2020-001041-S
Faster ocean warming threatens richest areas of marine biodiversity
First published: 07 July 2022The vulnerability of marine biodiversity to accelerated rates of climatic change is poorly understood. By developing a new method for identifying extreme oceanic warming events during Earth's most recent deglaciation, and comparing these to 21st century projections, we show that future rates of ocean warming will disproportionately affect the most speciose marine communities, potentially threatening biodiversity in more than 70% of current-day global hotspots of marine species richness. The persistence of these richest areas of marine biodiversity will require many species to move well beyond the biogeographic realm where they are endemic, at rates of redistribution not previously seen. Our approach for quantifying exposure of biodiversity to past and future rates of oceanic warming provides new context and scalable information for deriving and strengthening conservation actions to safeguard marine biodiversity under climate change.Stuart C. Brown, Camille Mellin, Jorge García Molinos, Eline D. Lorenzen, Damien A. Fordha
Pilot study on university students' opinion about STEM studies at higher education
The percentages of women enrolled in higher education in the
STEM sector are significantly lower than those of men. Overall,
gender representation in science, technology, engineering and mathematics
degrees in Europe is not balanced. The Leaky Pipeline phenomenon,
marked by gender stereotypes, makes the latent gender
gap a relevant topic of study. Studies exist on academic performance,
self-perception, self-efficacy, outcome expectations; however, studying
gender stereotypes linked to STEM studies is also essential. It
is necessary to know the social and family context in which young
people have grown up, as well as their perception of such studies.
To study gender stereotypes of university students about STEM
studies, a questionnaire has been designed for empirical validation.
For the design of the instrument, to be validated, items from other
instruments have been taken and adapted to Spanish. After the
design of the instrument, an online pilot study has been applied
in the University of Salamanca, the University of Valencia and the
Polytechnic University of Valencia. A total of 115 people answered
the questionnaire. The results of the pilot study reveal that the
study sample is not particularly marked by gender stereotypes
about gender equality in STEM. Also, the sample is receptive to
learning about science and applying it in their lives. On the other
hand, the idea that women have to give up their studies and careers
to look after their families and children is rejected. The idea that
men are more interested in university studies than women is also
rejected. At the same time, the sample is aware of the difficulties
that women encounter in the STEM sector. Another optimistic point
of the results is that there are no alarming data on bad experiences
due to gender. In the future, the study will be replicated on a larger
scale
- …