cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Need Satisfaction and Millennials' Worries About College
Creators: name: Greene, Nathaniel
name: Fuentes, Julian
Publisher: name: Open Science Framework
Year: 2022
Subjects: subject: Family achievement guilt
subject: Millennials
subject: Need satisfaction
subject: Parent-student relationship
subject: Self-determination theory
subject: Student worries

description: We endeavored to determine whether need satisfaction in the parental relationship would negatively predict millennials' worries and feelings of family achievement guilt during the transition to college in a sample of first- and continuing-generation students. We also explored whether two contradictory types of parental involvement - autonomy-supportive parenting and helicopter parenting - moderated these relationships, and whether the outcomes were similar for first- and continuing-generation students. Incoming college freshmen (N = 355) completed measures of parental relationship need satisfaction, parental involvement, worries about college, and family achievement guilt. Higher levels of need satisfaction in the parental relationship were associated with lower levels of worry and achievement guilt, and autonomy-supportive parenting moderated the relationship between autonomy satisfaction and millennials' worries about college. There were no differences in any of the outcomes examined in this study between first- and continuing-generation students.
Extending Topological Surgery to Natural Processes and Dynamical Systems
Creators: name: Lambropoulou, Sofia
name: Antoniou, Stathis
Publisher: name: arXiv
Year: 2016
Subjects: subject: Geometric Topology (math.GT)
subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics
subject: 57R65, 57N12, 57M25, 57M99, 37B99, 92B99

description: Topological surgery is a mathematical technique used for creating new manifolds out of known ones. We observe that it occurs in natural phenomena where a sphere of dimension 0 or 1 is selected, forces are applied and the manifold in which they occur changes type. For example, 1-dimensional surgery happens during chromosomal crossover, DNA recombination and when cosmic magnetic lines reconnect, while 2-dimensional surgery happens in the formation of tornadoes, in the phenomenon of Falaco solitons, in drop coalescence and in the cell mitosis. Inspired by such phenomena, we introduce new theoretical concepts which enhance topological surgery with the observed forces and dynamics. To do this, we first extend the formal definition to a continuous process caused by local forces. Next, for modeling phenomena which do not happen on arcs or surfaces but are 2-dimensional or 3-dimensional, we fill in the interior space by defining the notion of solid topological surgery. We further introduce the notion of embedded surgery in $S^3$ for modeling phenomena which involve more intrinsically the ambient space, such as the appearance of knotting in DNA and phenomena where the causes and effect of the process lies beyond the initial manifold, such as the formation of black holes. Finally, we connect these new theoretical concepts with a dynamical system and we present it as a model for both 2-dimensional 0-surgery and natural phenomena exhibiting a `hole drilling' behavior. We hope that through this study, topology and dynamics of many natural phenomena, as well as topological surgery itself, will be better understood.
description: 54 pages, 34 figures
Loop corrections to the antibrane potential
Creators: name: Bena, Iosif
name: Blåbäck, Johan
name: Turton, David
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Antibranes provide some of the most generic ways to uplift Anti-de Sitter flux compactifications to de Sitter, and there is a growing body of evidence that antibranes placed in long warped throats such as the Klebanov-Strassler warped deformed conifold solution have a brane-brane-repelling tachyon. This tachyon was first found in the regime of parameters in which the backreaction of the antibranes is large, and its existence was inferred from a highly nontrivial cancellation of certain terms in the inter-brane potential. We use a brane effective action approach, similar to that proposed by Michel, Mintun, Polchinski, Puhm and Saad in arXiv:1412.5702, to analyze antibranes in Klebanov-Strassler when their backreaction is small, and find a regime of parameters where all perturbative contributions to the action can be computed explicitly. We find that the cancellation found at strong coupling is also present in the weak-coupling regime, and we establish its existence to all loops. Our calculation indicates that the spectrum of the antibrane worldvolume theory is not gapped, and may generically have a tachyon. Hence uplifting mechanisms involving antibranes remain questionable even when backreaction is small.
description: 27 pages, 5 figures, v2: Added clarification of statements, version accepted for publication in JHEP
Elementary construction of residue currents associated to Cohen-Macaulay ideals
Creators: name: Lärkäng, Richard
name: Mazzilli, Emmanuel
Publisher: name: arXiv
Year: 2016
Subjects: subject: Complex Variables (math.CV)
subject: FOS: Mathematics

description: For a Cohen-Macaulay ideal of holomorphic functions, we construct by elementary means residue currents whose annihilator is precisely the given ideal. We give two proofs that the currents have the prescribed annihilator, one using the theory of linkage, and another using an explicit division formula involving these residue currents to express the ideal membership.
description: 11 pages. Final version to appear in Annales de Fourier
Gravitational wave transient signal emission via Ekman pumping in neutron stars during post-glitch relaxation phase
Creators: name: Singh, Avneet
Publisher: name: arXiv
Year: 2016
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Glitches in the rotational frequency of a spinning neutron star could be promising sources of gravitational wave signals lasting between a few microseconds to a few weeks. The emitted signals and their properties depend upon the internal properties of the neutron star. In neutron stars, the most important physical properties of the fluid core are the viscosity of the fluid, the stratification of flow in the equilibrium state and the adiabatic sound speed. Such models were previously studied by van Eysden and Melatos [73] and Bennett et al. [26] following simple assumptions on all contributing factors, in which the post-glitch relaxation phase could be driven by the well-known process of Ekman pumping [76, 17]. We explore the hydrodynamic properties of the flow of fluid during this phase following more relaxed assumptions on the stratification of flow and the pressure-density gradients within the neutron star than previously studied. We calculate the time-scales of duration as well as the amplitudes of the resulting gravitational wave signals, and we detail their dependence on the physical properties of the fluid core. We find that it is possible for the neutron star to emit gravitational wave signals in a wide range of decay time-scales and within the detection sensitivity of aLIGO for selected domains of physical parameters.
description: 24 pages, 11 figures; v1: initial submission; v2: internal review; v3: journal review; v4: copyedited version; v5-6: minor typos corrected and references updated; v7 (final): corrections in metadata
An Explicit Rate Bound for the Over-Relaxed ADMM
Creators: name: França, Guilherme
name: Bento, José
Publisher: name: arXiv
Year: 2015
Subjects: subject: Machine Learning (stat.ML)
subject: Optimization and Control (math.OC)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: The framework of Integral Quadratic Constraints of Lessard et al. (2014) reduces the computation of upper bounds on the convergence rate of several optimization algorithms to semi-definite programming (SDP). Followup work by Nishihara et al. (2015) applies this technique to the entire family of over-relaxed Alternating Direction Method of Multipliers (ADMM). Unfortunately, they only provide an explicit error bound for sufficiently large values of some of the parameters of the problem, leaving the computation for the general case as a numerical optimization problem. In this paper we provide an exact analytical solution to this SDP and obtain a general and explicit upper bound on the convergence rate of the entire family of over-relaxed ADMM. Furthermore, we demonstrate that it is not possible to extract from this SDP a general bound better than ours. We end with a few numerical illustrations of our result and a comparison between the convergence rate we obtain for the ADMM with known convergence rates for the Gradient Descent.
description: IEEE International Symposium on Information Theory (ISIT), 2016
Flow analysis of the low-Reynolds number swimmer C. elegans
Creators: name: Montenegro-Johnson, Thomas D.
name: Gagnon, David A.
name: Arratia, Paulo E.
name: Lauga, Eric
Publisher: name: arXiv
Year: 2016
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Soft Condensed Matter (cond-mat.soft)
subject: Biological Physics (physics.bio-ph)
subject: FOS: Physical sciences

description: Swimming cells and microorganisms are a critical component of many biological processes. In order to better interpret experimental studies of low Reynolds number swimming, we combine experimental and numerical methods to perform an analysis of the flow-field around the swimming nematode Caenorhabditis elegans. We first use image processing and particle tracking velocimetry to extract the body shape, kinematics, and flow-fields around the nematode. We then construct a three-dimensional model using the experimental swimming kinematics and employ a boundary element method to simulate flow-fields, obtaining very good quantitative agreement with experiment. We use this numerical model to show that calculation of flow shear rates using purely planar data results in significant underestimates of the true three-dimensional value. Applying symmetry arguments, validated against numerics, we demonstrate that the out-of-plane contribution can be accounted for via incompressibility and therefore simply calculated from particle tracking velocimetry. Our results show how fundamental fluid mechanics considerations may be used to improve the accuracy of measurements in biofluiddynamics.
Quantum metrology with full and fast quantum control
Creators: name: Sekatski, Pavel
name: Skotiniotis, Michalis
name: Kołodyński, Janek
name: Dür, Wolfgang
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We establish general limits on how precise a parameter, e.g. frequency or the strength of a magnetic field, can be estimated with the aid of full and fast quantum control. We consider uncorrelated noisy evolutions of N qubits and show that fast control allows to fully restore the Heisenberg scaling (~1/N^2) for all rank-one Pauli noise except dephasing. For all other types of noise the asymptotic quantum enhancement is unavoidably limited to a constant-factor improvement over the standard quantum limit (~1/N) even when allowing for the full power of fast control. The latter holds both in the single-shot and infinitely-many repetitions scenarios. However, even in this case allowing for fast quantum control helps to increase the improvement factor. Furthermore, for frequency estimation with finite resource we show how a parallel scheme utilizing any fixed number of entangled qubits but no fast quantum control can be outperformed by a simple, easily implementable, sequential scheme which only requires entanglement between one sensing and one auxiliary qubit.
description: 17 pages, 7 figures, 6 appendices
Exploiting a Geometrically Sampled Grid in the SRP-PHAT for Localization Improvement and Power Response Sensitivity Analysis
Creators: name: Salvati, Daniele
name: Drioli, Carlo
name: Foresti, Gian Luca
Publisher: name: arXiv
Year: 2015
Subjects: subject: Sound (cs.SD)
subject: FOS: Computer and information sciences

description: The steered response power phase transform (SRP-PHAT) is a beamformer method very attractive in acoustic localization applications due to its robustness in reverberant environments. This paper presents a spatial grid design procedure, called the geometrically sampled grid (GSG), which aims at computing the spatial grid by taking into account the discrete sampling of time difference of arrival (TDOA) functions and the desired spatial resolution. A new SRP-PHAT localization algorithm based on the GSG method is also introduced. The proposed method exploits the intersections of the discrete hyperboloids representing the TDOA information domain of the sensor array, and projects the whole TDOA information on the space search grid. The GSG method thus allows to design the sampled spatial grid which represents the best search grid for a given sensor array, it allows to perform a sensitivity analysis of the array and to characterize its spatial localization accuracy, and it may assist the system designer in the reconfiguration of the array. Experimental results using both simulated data and real recordings show that the localization accuracy is substantially improved both for high and for low spatial resolution, and that it is closely related to the proposed power response sensitivity measure.
Physical properties of galaxies: toward a consistent comparison between hydrodynamical simulations and SDSS
Creators: name: Guidi, Giovanni
name: Scannapieco, Cecilia
name: Walcher, C. Jakob
name: Gallazzi, Anna
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We study the effects of applying observational techniques to derive the properties of simulated galaxies, with the aim of making an unbiased comparison between observations and simulations. For our study, we used fifteen galaxies simulated in a cosmological context using three different feedback and chemical enrichment models, and compared their z=0 properties with data from the Sloan Digital Sky Survey (SDSS). We show that the physical properties obtained directly from the simulations without post-processing can be very different to those obtained mimicking observational techniques. In order to provide simulators a way to reliably compare their galaxies with SDSS data, for each physical property that we studied - colours, magnitudes, gas and stellar metallicities, mean stellar ages and star formation rates - we give scaling relations that can be easily applied to the values extracted from the simulations. These scalings have in general a high correlation, except for the galaxy mean stellar ages and gas oxygen metallicities. Our simulated galaxies are photometrically similar to galaxies in the blue cloud/green valley, but in general they appear older, passive and with lower metal content compared to most of the spirals in SDSS. As a careful assessment of the agreement/disagreement with observations is the primary test of the baryonic physics implemented in hydrodynamical codes, our study shows that considering the observational biases in the derivation of the galaxies' properties is of fundamental importance to decide on the failure/success of a galaxy formation model.
description: 19 pages, 18 figures, accepted for publication by MNRAS
Improving the Single Scalar Consistency Relation
Creators: name: Brooker, D. J.
name: Tsamis, N. C.
name: Woodard, R. P.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We propose a test of single-scalar inflation based on using the well-measured scalar power spectrum to reconstruct the tensor power spectrum, up to a single integration constant. Our test is a sort of integrated version of the single-scalar consistency relation. This sort of test can be used effectively, even when the tensor power spectrum is measured too poorly to resolve the tensor spectral index. We give an example using simulated data based on a hypothetical detection with tensor-to-scalar ratio $r = 0.01$. Our test can also be employed for correlating scalar and tensor features in the far future when the data is good.
description: 16 pages, 1 figure, uses LaTeX2e version 2 extensively revised for publication
The Monge-Ampère equation for non-integrable almost complex structures
Creators: name: Chu, Jianchun
name: Tosatti, Valentino
name: Weinkove, Ben
Publisher: name: arXiv
Year: 2016
Subjects: subject: Analysis of PDEs (math.AP)
subject: Differential Geometry (math.DG)
subject: FOS: Mathematics
subject: 32Q60, 32W20, 35J96, 53C15

description: We show existence and uniqueness of solutions to the Monge-Ampere equation on compact almost complex manifolds with non-integrable almost complex structure.
description: 38 pages; final version to appear in JEMS
A first theoretical realization of honeycomb topological magnon insulator
Creators: name: Owerre, S. A.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: It has been recently shown that in the Heisenberg (anti)ferromagnet on the honeycomb lattice, the magnons (spin wave quasipacticles) realize a massless two-dimensional (2D) Dirac-like Hamiltonian. It was shown that the Dirac magnon Hamiltonian preserves time-reversal symmetry defined with the sublattice pseudo spins and the Dirac points are robust against magnon-magnon interactions. The Dirac points also occur at nonzero energy. In this paper, we propose a simple realization of nontrivial topology (magnon edge states) in this system. We show that the Dirac points are gapped when the inversion symmetry of the lattice is broken by introducing a next-nearest neighbour Dzyaloshinskii-Moriya (DM) interaction. Thus, the system realizes magnon edge states similar to Haldane model for quantum anomalous Hall effect in electronic systems. However, in contrast to electronic spin current where dissipation can be very large due to Ohmic heating, noninteracting topological magnons can propagate for long time without dissipation as magnons are uncharged particles. We observe the same magnon edge states for the XY model on the honeycomb lattice. Remarkably, in this case the model maps to interacting hardcore bosons on the honeycomb lattice. Quantum magnetic systems with nontrivial magnon edge states are called topological magnon insulators. They have been studied theoretically on the kagome lattice and recently observed experimentally on the kagome magnet Cu(1-3, bdc) with three magnon bulk bands. Our results for the honeycomb lattice suggests an experimental procedure to search for honeycomb topological magnon insulators within a class of 2D quantum magnets and ultracold atoms trapped in honeycomb optical lattices.
description: 12 pages with 6 figures. Published version
Effects and consequences of implementing citizen-science programmes in schools in an environmentally, economically and socially challenged urban district. REGREEN Deliverable D5.4.
Creators: name: Sierra-Jimenez, Mara
name: Prévot, Anne-Caroline
name: Benateau, Simon
name: Turpin, Sebastien
Publisher: name: REGREEN Fostering nature‐based solutions for smart, green and healthy urban transitions in Europe and China.
Year: 2022
Subjects: Vigie Nature Ecole
nature education
Children
equity

description: An an era of over urbanisation and disconnection to living world in Western countries, this report refers to a survey of two‐years experiment in fifteen schools in Paris‐region, France including students aged 3 to 18. In these schools, volunteering teachers have implemented citizen‐science programmes on common biodiversity with theirstudents, and combined these observations with initiatives toward biodiversity in the schoolyards. Citizen‐science programmes were part of the French national Vigie‐Nature Ecole programme (VNE), developed by the French National Museum of Natural History (MNHN). Teachers were also invited by the research MNHN team to deploy some other pedagogical approaches to enrich the emotional and affective bonds of students with nature. 

As shown by the 2‐years survey of the involved classes, the implementation of VNE in classes is challenging because it changes many pedagogical and educational routines. The first year is a fundamentalstage in the learning process ofscientific pedagogy, during which the teacher observes, discovers, seeks out and trains himself and his pupils. It is a moment of transition between the known pedagogical comfort zone and the discovery of new possibilities. During the following years, teachers explore more in‐depth the proposed educational tools, and enrich their pedagogical activities, to become innovative in a diversity of initiatives.  

Regarding children and young adults, observing common natural species (birds, insects, earthworms, snails, plants) in the schoolyard is the opportunity to discover a new world (for some of them), to increase their awareness toward nature, but also to open new emotional bonds to nature. With these two‐year experiments, we highlighted the complementarity of scientific and sensitive approaches to increase the awareness of students from all ages to surrounding nature, in a very urbanised context.
Η αποτύπωση της πολιτικής φιλοσοφίας του Νεορεαλισμού και η αισθητική του εκφορά σε εικαστικά και κινηματογραφικά έργα τέχνης
Creators: name: Καπετάνου, Δημήτριος Γεωργίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2023
Subjects: Νεορεαλισμός
Αισθητική του Κινηματογράφου
Εικαστικές και Εφαρμοσμένες Τέχνες
Neorealism
Aesthetic of Cinema
Fine and Applied Arts

description: Σκοπός της μεταπτυχιακής συγγραφικής διατριβής, υπήρξε η ανάλυση του Νεορεαλισμού ως φιλοσοφικό κίνημα, και ο τρόπος με τον οποίο αποτυπώθηκε σε κινηματογραφικά, λογοτεχνικά και εικαστικά έργα τέχνης. Λαμβάνοντας υπόψιν τα χρόνια στα οποία ο Νέος Ρεαλισμός γεννήθηκε και έπειτα αναπτύχθηκε, αναδεικνύεται η ανάγκη υποστήριξης έργων τέχνης με σαφές κοινωνικό πρόσημο, κάτι που μέχρι τότε γινόταν αλλά με όχι τόσο έντονο τρόπο. Επίσης μελετάται πόσο πολύ βοηθήθηκε το κίνημα από πολιτικο – οικονομικούς παράγοντες όσο και από πολιτιστικούς. Το κίνημα αυτό δεν λογοκρίθηκε ποτέ, με αποτέλεσμα να βρει παγκόσμια αναγνώριση και να επηρεάσει κάθε μορφή τέχνης τις επόμενες δεκαετίες.
description: The purpose of the master's thesis was the analysis of Neorealism as a philosophical movement, and the way in which it was reflected in cinematographic, literary and visual works of art. Taking into account the years in which New Realism was born and then developed, the need to support works of art with a clear social sign emerges, something that was done until then but in a less intense way. It is also studied how much the movement was helped by political-economic factors as well as by cultural ones. This movement was never censored, as a result it found worldwide recognition and influenced every form of art for decades to come.
The Local Fractional Bootstrap
Creators: name: Bennedsen, Mikkel
name: Hounyo, Ulrich
name: Lunde, Asger
name: Pakkanen, Mikko S.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Statistics Theory (math.ST)
subject: Statistical Finance (q-fin.ST)
subject: FOS: Mathematics
subject: FOS: Economics and business
subject: 60G10, 60G15, 60G17, 60G22, 62M07, 62M09, 65C05

description: We introduce a bootstrap procedure for high-frequency statistics of Brownian semistationary processes. More specifically, we focus on a hypothesis test on the roughness of sample paths of Brownian semistationary processes, which uses an estimator based on a ratio of realized power variations. Our new resampling method, the local fractional bootstrap, relies on simulating an auxiliary fractional Brownian motion that mimics the fine properties of high frequency differences of the Brownian semistationary process under the null hypothesis. We prove the first order validity of the bootstrap method and in simulations we observe that the bootstrap-based hypothesis test provides considerable finite-sample improvements over an existing test that is based on a central limit theorem. This is important when studying the roughness properties of time series data; we illustrate this by applying the bootstrap method to two empirical data sets: we assess the roughness of a time series of high-frequency asset prices and we test the validity of Kolmogorov's scaling law in atmospheric turbulence data.
Ionenkanäle in deaktivierter Mikroglia
Creators: name: Eder, Claudia
Publisher: name: Humboldt-Universität zu Berlin, Medizinische Fakultät - Universitätsklinikum Charité
Year: 2001
Subjects: subject: Mikroglia
subject: Ionenkanäle
subject: Patch-clamp-Technik
subject: Deaktivierung
subject: Microglia
subject: ion channels
subject: patch clamp technique
subject: deactivation
subject: 610 Medizin
subject: 33 Medizin
subject: WW 1620

description: In der vorliegenden Habilitationsarbeit wurden die Ionenkanäle von Mikrogliazellen mit Hilfe der Patch-clamp-Technik untersucht, nachdem die Mikrogliazellen in den deaktivierten Zustand überführt worden waren. Die Deaktivierung der Mikroglia erfolgte durch die Zugabe des astrozytenkonditionierten Mediums. Nach der Deaktivierung exprimierten die Mikrogliazellen einwärts- und auswärtsgleichrichtende sowie Ca2+-aktivierte Kaliumkanäle. Der auswärtsgleichrichtende Kaliumkanal wurde erst nach Zugabe des astrozytenkonditionierten Mediums exprimiert, wobei das durch die Astrozyten freigesetzte Zytokin transformierender Wachstumsfaktor für diesen Prozeß verantwortlich gemacht werden konnte. Zusätzlich wurden Chloridkanäle an deaktivierten Mikrogliazellen nachgewiesen, die an den Ramifizierungsprozessen der Zellen, d.h. dem Übergang von der amöboiden in die ramifizierte Zellmorphologie, beteiligt waren. Die an Mikrogliazellen exprimierten Protonenkanäle spielen offensichtlich eine wichtige Rolle bei der Generierung von reaktiven Sauerstoffradikalen und wurden im Prozeß der Deaktivierung der Mikrogliazellen herunterreguliert.
description: The current work describes patch clamp recordings in cultured murine microglial cells, which had been deactivated following exposure to astrocyte-conditioned medium. Deactivated microglial cells expressed inwardly rectifying, outwardly rectifying and calcium-activated potassium channels. The outwardly rectifying potassium channels were upregulated following treatment of microglial cells with the astrocyte-conditioned medium. The anti-inflammatory cytokine transforming growth factor was released by astrocytes and appeared to be responsible for the observed upregulation of outwardly rectifying potassium channels in deactivated microglia. In addition, deactivated microglial cells expressed chloride channels, which were found to be involved in microglial ramification, i.e., in the transformation of microglial cells from ameboid into ramified morphology. Voltage-gated proton channels, which are involved in processes of oxygen radical generation, were downregulated in deactivated microglial cells.
The Co-Evolution of Total Density Profiles and Central Dark Matter Fractions in Simulated Early-Type Galaxies
Creators: name: Remus, Rhea-Silvia
name: Dolag, Klaus
name: Naab, Thorsten
name: Burkert, Andreas
name: Hirschmann, Michaela
name: Hoffmann, Tadziu L.
name: Johansson, Peter H.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We present evidence from cosmological hydrodynamical simulations for a co-evolution of the slope of the total (dark and stellar) mass density profile, gamma_tot, and the dark matter fraction within the half-mass radius, f_DM, in early-type galaxies. The relation can be described as gamma_tot = A f_DM + B for all systems at all redshifts. The trend is set by the decreasing importance of gas dissipation towards lower redshifts and for more massive systems. Early-type galaxies are smaller, more concentrated, have lower f_DM and steeper gamma_tot at high redshifts and at lower masses for a given redshift; f_DM and gamma_tot are good indicators for growth by "dry" merging. The values for A and B change distinctively for different feedback models, and this relation can be used as a test for such models. A similar correlation exists between gamma_tot and the stellar mass surface density Sigma_*. A model with weak stellar feedback and feedback from black holes is in best agreement with observations. All simulations, independent of the assumed feedback model, predict steeper gamma_tot and lower f_DM at higher redshifts. While the latter is in agreement with the observed trends, the former is in conflict with lensing observations, which indicate constant or decreasing gamma_tot. This discrepancy is shown to be artificial: the observed trends can be reproduced from the simulations using observational methodology to calculate the total density slopes.
description: 17 pages, 10 figures, published by MNRAS
Issues Within the Sri Lankan Tamil Community During the Covid Pandemic in England and How These Challenges Were and Continue to be Met
Creators: name: Parameswaran, S.
Publisher: name: Living Refugee Archive, University of East London
Year: 2023

description: The operation of the 24-hour Tamil Helpline and groups that sprung up during the Covid pandemic within the Sri Lankan Tamil community in England, have played a vital role in maintaining the wellbeing of this community. These initiatives were set up in response to concerns expressed and an apparent need from within the community. In this connection, information sharing, education and mutual support has played an important role towards understanding and taking responsibility for the individual, familial and community’s wellbeing. The success of these initiatives can also be attributed to the community as a whole responding to the crisis and the associated benefits of knowing support was available from trusted professional members from within their community. It appears that strengthening social connections and undertaking health enhancing activities, particularly exercise and maintaining a daily routine was helpful. Regular zoom sessions relating to exercise and information sharing were available in the Tamil language, these were well attended by people from across the UK in addition to a number of other countries.
Symmetry reduction and exact solutions of the non-linear Black--Scholes equation
Creators: name: Patsiuk, Oleksii
name: Kovalenko, Sergii
Publisher: name: arXiv
Year: 2015
Subjects: subject: Mathematical Finance (q-fin.MF)
subject: FOS: Economics and business
subject: 22E99, 35Q91, 91G80

description: In this paper, we investigate the non-linear Black--Scholes equation: $$u_t+ax^2u_{xx}+bx^3u_{xx}^2+c(xu_x-u)=0,\quad a,b>0,\ c\geq0.$$ and show that the one can be reduced to the equation $$u_t+(u_{xx}+u_x)^2=0$$ by an appropriate point transformation of variables. For the resulting equation, we study the group-theoretic properties, namely, we find the maximal algebra of invariance of its in Lie sense, carry out the symmetry reduction and seek for a number of exact group-invariant solutions of the equation. Using the results obtained, we get a number of exact solutions of the Black--Scholes equation under study and apply the ones to resolving several boundary value problems with appropriate from the economic point of view terminal and boundary conditions.
description: Published version, 16 pages (in preprint, 10 pages in print), 2 figures
Pomeron Interactions from the Einstein-Hilbert Action
Creators: name: Iatrakis, Ioannis
name: Ramamurti, Adith
name: Shuryak, Edward
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Holographic models of QCD, collectively known as AdS/QCD, have been proven useful in deriving several properties of hadrons. One particular feature well reproduced by such models is the Regge trajectories, both for mesons and glueballs. We focus on scalar and tensor glueballs, and derive an effective theory for the Pomeron by analytic continuation along the leading trajectory from the tensor glueball. It then follows that the Pomeron, as the tensor glueball itself, should possess a two-index polarization tensor, inherited from the graviton. The three-graviton interaction is deduced from the Einstein-Hilbert action. Using this structure in the cross section of double-Pomeron production of the tensor glueball, we calculate certain angular distributions of production and compare them with those from the CERN WA102 experiment. We find that the agreement is very good for the $f_2(2300)$ tensor glueball candidate. At the same time, other tensor states -- such as $f_2(1270)$ and $f'_2(1520)$ -- have completely different distributions, which we interpret as consequence of the fact that they are not glueballs and thus, in our model, unrelated to the gravitational excitations, which are dual to spin-2 glueballs.
description: 10 pages, 4 figures
title: Διαχείριση διαδικασιών σε ιατρικές εφαρμογές με τη χρήση τρισδιάστατων τεχνικών
title: Process management in medical applications with the use of 3D techniques
titleType: AlternativeTitle
Creators: name: Σπυρόπουλος, Γεώργιος Άγγελος
Publisher: name: Πανεπιστήμιο Πειραιώς
Year: 2023
Subjects: subject: Αντίστροφη μηχανική
subject: Προσθετική μηχανική
subject: Διαχείριση διαδικασιών
subject: Ιατρικός τομέας
subject: Τρισδιάστατη σάρωση
subject: Τρισδιάστατη εκτύπωση

description: Οι τρισδιάστατες τεχνικές είναι μία τεχνολογία που μπορεί να φέρει επανάσταση στον ιατρικό τομέα όσον αφορά την προσαρμογή και την εξατομίκευση. Διάφορες μελέτες και εν εξελίξει πρακτικές, που πληθαίνουν όλο και περισσότερο, έχουν αποδείξει τις δυνατότητες των τρισδιάστατων τεχνικών στην ιατρική. Παρόλα αυτά, για να μπορέσουν να υιοθετηθούν θα πρέπει να εξεταστεί η επίπτωση στις διαδικασίες, που μπορεί να συμβάλουν με τον βέλτιστο τρόπο. Ο σκοπός αυτής της διπλωματικής εργασίας είναι να εξετάσει πως με τη χρήση τρισδιάστατων τεχνικών διαχειρίζονται οι διαδικασίες στον ιατρικό τομέα. Αρχικά, αναλύθηκε η τρισδιάστατη τεχνική της προσθετικής κατασκευής ή αλλιώς της τρισδιάστατης εκτύπωσης. Η βιβλιογραφική έρευνα κατέδειξε τις διεργασίες προσθετικής κατασκευής, εστιάζοντας στη συνέχεια στις χρήσεις της στον ιατρικό τομέα, όπου παρατηρήθηκε η αύξηση των δημοσιεύσεων τα τελευταία χρόνια. Με την χρήση της παρούσας βιβλιογραφίας, ταξινομήθηκαν οι ιατρικές εφαρμογές της προσθετικής κατασκευής σε πέντε τομείς και αναλύθηκαν οι χρήσεις τους. Στη συνέχεια, εντοπίστηκε και αναλύθηκε η διαδικασία της παραγωγής προσθετικής κατασκευής για ένα ιατρικό προϊόν. Για να υπάρξει η υιοθέτηση της προσθετικής κατασκευής στην ιατρική θα πρέπει να υπάρξει μελέτη για τις επιπτώσεις της στις ήδη υπάρχουσες διαδικασίες και η δυνατότητά της για την μεταμόρφωσή τους. Κατα συνέπεια, έξι παράγοντες διαδραματίζουν ζωτικό ρόλο στο αντίκτυπο των διαδικασιών διαχείρισης της προσθετικής κατασκευής. Η γέννηση ενός υβριδικού ρόλου επηρεάζει το ιατρικό οικοσύστημα και η εκάστοτε δίοικηση του κάθε οργανισμού βρέθηκε πως θα είναι από τους βασικούς παράγοντες υιοθέτησής της. Τέλος, με την χρήση της αντίστροφης μηχανικής-τρισδιάστατης σάρωσης πραγματοποιήθηκε το πειραματικό στάδιο της σάρωσης ενός μοντέλου ανθρώπινου μηριαίου οστού και με την βοήθεια σχεδιστικού λογισμικού και της τρισδιάστατης εκτύπωσης, τυπώθηκε μία χειρουργική πλάκα.
Η έννοια της διαδρομής ως αναπόσπαστο κομμάτι της ταξιδιωτικής εμπειρίας και η συμπεριφορά του ταξιδιώτη κατά τη διάρκεια αυτής
Creators: name: Μαργαλιά, Αναστασία Νεφέλη
Publisher: name: Πανεπιστήμιο Πειραιώς
Year: 2022
Subjects: subject: Τουρισμός
subject: Πολλαπλοί προορισμοί
subject: Συμβατικοί τουρίστες
subject: Περιπέτεια
subject: Road trip
subject: Backpacking
subject: Μοναδικός προορισμός
subject: Εναλλακτικός τουρισμός
subject: Συνεντεύξεις

description: Η παρούσα εργασία αποσκοπεί στην κατανόηση της ταξιδιωτικής συμπεριφοράς ορισμένων τουριστών οι οποίοι επιλέγουν να μετακινηθούν σε διαφορετικά μέρη σε ένα ταξίδι τους και δεν παραμένουν σε έναν συγκεκριμένο προορισμό. Πιο αναλυτικά, ερευνώνται οι λόγοι για τους οποίους η διαδρομή για κάποιους ταξιδιώτες είναι πιο σημαντική από τον τελικό προορισμό και ποιες είναι οι διαφορές με τους τουρίστες που επιλέγουν να διαμένουν σε ένα μέρος καθ’ όλη τη διάρκεια των διακοπών τους. Στο πρώτο κεφάλαιο παρουσιάζεται ο εναλλακτικός τουρισμός και οι μορφές του, τα οφέλη του, οι διαφορές των εναλλακτικών και των μαζικών τουριστών καθώς και κάποια παγκόσμια στατιστικά στοιχεία του εναλλακτικού τουρισμού. Στο δεύτερο κεφάλαιο αναλύεται ο τουρισμός περιπέτειας. Πιο συγκεκριμένα, οι δραστηριότητες που περιλαμβάνει, τα χαρακτηριστικά των ταξιδιωτών που επιλέγουν το συγκεκριμένο είδος τουρισμού και παρουσιάζονται και κάποια στατιστικά στοιχεία από όλο τον κόσμο. Επιπροσθέτως, γίνεται μια εκτενής αναφορά στο backpacking και το road trip αλλά και στις διαφορές μεταξύ των τουριστών που επιλέγουν έναν προορισμό και σε αυτούς που επισκέπτονται πολλές διαφορετικές περιοχές κατά τη διάρκεια του ταξιδιού τους. Για να μπορέσει να διερευνηθεί ο σκοπός της παρούσας έρευνας πραγματοποιήθηκε ποιοτική έρευνα μέσω ατομικών συνεντεύξεων σε 8 άτομα, εκ των οποίων οι 5 είναι οι περιπετειώδες τουρίστες και οι 3 οι περισσότερο συμβατικοί. Έτσι, στο τρίτο κεφάλαιο επισημαίνεται η ερευνητική μεθοδολογία όσον αφορά το δείγμα, η διάρκεια της έρευνας που ήταν 6 μήνες και οι δυσκολίες που προέκυψαν κατά την εκπόνησή της αλλά και η διαμόρφωση των συνεντεύξεων. Στο τέταρτο κεφάλαιο παρουσιάζονται τα αποτελέσματα των συνεντεύξεων και εν τέλει τα συμπεράσματα της έρευνας.
Identities between Modular Graph Forms
Creators: name: D'Hoker, Eric
name: Green, Michael B.
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Number Theory (math.NT)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: This paper investigates the relations between modular graph forms, which are generalizations of the modular graph functions that were introduced in earlier papers motivated by the structure of the low energy expansion of genus-one Type II superstring amplitudes. These modular graph forms are multiple sums associated with decorated Feynman graphs on the world-sheet torus. The action of standard differential operators on these modular graph forms admits an algebraic representation on the decorations. First order differential operators are used to map general non-holomorphic modular graph functions to holomorphic modular forms. This map is used to provide proofs of the identities between modular graph functions for weight less than six conjectured in earlier work, by mapping these identities to relations between holomorphic modular forms which are proven by holomorphic methods. The map is further used to exhibit the structure of identities at arbitrary weight.
description: 56 pages; minor typos corrected and showlabels deleted in version 2; minor corrections in preparation for publication in Journal of Number Theory in version 3
Μελέτη σκοπιμότητας ίδρυσης μονάδας παραγωγής και εμπορίας ελαιόλαδων
Creators: name: Δημοκρασσάς, Γρηγόριος
Publisher: name: Πανεπιστήμιο Πειραιώς
Year: 2023
Subjects: subject: Προϊόν
subject: Τιμή
subject: Τόπος διανομής
subject: Προώθηση
subject: Μίγμα μάρκετινγκ
subject: Ελαιόλαδο

description: Μέσα από την παρούσα εργασία αναπτύσσεται ένα επιχειρηματικό σχέδιο για μια νέα εταιρεία που θα ασχοληθεί με την τυποποίηση ελαιόλαδου. Η ανάλυση των δεδομένων και των προβλέψεων έχει αναδείξει ορισμένα συμπεράσματα σχετικά με τη βιωσιμότητα της επιχειρηματικής ιδέας. Σκοπός του τρέχοντος επιχειρηματικού σχεδίου είναι η περιγραφή της δομής και των λειτουργιών της επιχείρησης καθώς και ο εντοπισμός των απαιτούμενων πόρων για την επίτευξη των στόχων που έχουν τεθεί. Κατ’ αυτόν τον τρόπο, εξετάστηκαν οι προοπτικές μιας νέας επιχειρηματικής προσπάθειας τυποποίησης ελαιόλαδου που θα εδρεύει στην πόλη της Καλαμάτας, μιας περιοχής πασίγνωστής για την ποιότητα της ελιάς και του ελαιόλαδου που παράγει. Ένα από τα βασικότερα σημεία του επιχειρηματικού σχεδίου που αναλύθηκε είναι το μίγμα μάρκετινγκ που αποτελείται από τις μεταβλητές του προϊόντος (Product), της τιμής (Price), του τόπου διανομής (Place) και της προώθησης (Promotion). Η εφαρμογή του μοντέλου αυτού στην περίπτωσή μας, απέδωσε στοιχεία που σχετίζονται με τη συσκευασία που θα κυκλοφορεί και θα παραπέμπει αυτομάτως σε ένα premium προϊόν, ενώ παράλληλα είναι πρακτική και εύχρηστη για τον καταναλωτή. Η πώληση του προϊόντος θα γίνεται μέσω όλων των καναλιών διανομής που είναι διαθέσιμα στην Ελληνική αγορά σε καταστήματα σούπερ μάρκετς, ντελικατέσεν, κουζίνες ξενοδοχείων και εστιατορίων υψηλών προδιαγραφών. Η τιμή λιανικής πώλησης θα τεθεί περίπου στα 10-11 ευρώ το λίτρο, περίπου στο μέσο του εύρους των λιανικών τιμών των εξαιρετικά παρθένων ελαιόλαδων της Ελληνικής αγοράς ενώ για την προώθηση του προϊόντος, η επιχείρηση θα χρησιμοποιήσει σύγχρονες μεθόδους τυποποίησης και μάρκετινγκ, στηριζόμενη στο συγκριτικό πλεονέκτημα της υψηλής ποιότητας του προϊόντος. Επιπλέον, θα υπάρχει υποστήριξη στο διαδίκτυο με ιστοσελίδα και χρήση των μέσων κοινωνικής δικτύωσης.
Health Outcomes and Language (HOLa) Scoping review of reviews
Creators: name: Jenstad, Lorienne
name: Abel, Jennifer
name: Mason, Glenda
name: Rieger, Caroline
name: Beck, Charlotte
name: Colozzo, Paola
name: Howe, Tami
name: Halas, Gayle
name: Breau, Genevieve
name: Lussier, Marie-Therese
name: Ribary, Urs
name: Strachan, Shaelyn
name: Sustersic, Melanie
name: Jagroop, Brenda
name: Bouthillier, Rafaelle
name: Simon, Leora
Publisher: name: Open Science Framework
Year: 2022

description: Scoping review of the question: "How is communication between health care provider and patient/caregiver linked to health outcomes?"
title: Σχεδιασμοί για πειράματα ανάμιξης υλικών
title: Order - of - addition experiments
titleType: AlternativeTitle
Creators: name: Σουρμελάκη, Ειρήνη Αγάπη
Publisher: name: Πανεπιστήμιο Πειραιώς
Year: 2023
Subjects: subject: Order - of Addition Experiments
subject: Σειρά Προσθήκης Μεταβλητών κατά ζεύγη - Pairwise ordering (PWO)
subject: D - αποδότικότητα (D – efficiency)
subject: Πλήρεις Παραγοντικοί Σχεδιασμοί (2k)
subject: Κλασματικοί Παραγοντικοί Σχεδιασμοί (2k-p)
subject: Οικονομικοί Order – of -Addition σχεδιασμοί
subject: Λατινικά Τετράγωνα

description: Στη παρούσα διπλωματική γίνεται αρχικά μία αναφορά στον ορισμό του πειράματος και τους στόχους του. Έπειτα ορίζεται ο στατιστικός πειραματικός σχεδιασμός, οι μέθοδοι, οι αρχές του και οι κατευθυντήριες γραμμές του, πως έχει εξελιχθεί ο πειραματικός σχεδιασμός μέσα στα χρόνια και πως χρησιμοποιήθηκε από διάφορες επιστήμες. Στο δεύτερο κεφάλαιο αναφέρονται οι μέθοδοι ανάλυσης των πειραματικών σχεδιασμών, αναλύονται οι πειραματικοί σχεδιασμοί με έναν ή και περισσότερους παράγοντες και περιγράφονται κάποια είδη σχεδιασμών (πλήρεις 2k και κλασματικοί 2k-p σχεδιασμοί). Η ανάπτυξη του τρίτου κεφαλαίου βασίζεται στη μελέτη της θεωρίας της σειράς ανάμειξης υλικών (Order – of – Addition experiments) σε έναν πειραματικό σχεδιασμό. Αναλυτικότερα, παρουσιάζεται ο πλήρης σχεδιασμός και οι ιδιότητες του υπό το πρίσμα της σειράς προσθήκης μεταβλητών (components) κατά ζεύγη (Pairwise ordering – PWO). Δίνεται παράδειγμα ενός PWO σχεδιασμού για τέσσερις μεταβλητές, πως μέσα από αυτόν μπορούν να παραχθούν οικονομικότεροι σχεδιασμοί με στόχο την εξοικονόμηση χρόνου και χρήματος και ορίζεται ένα μέτρο που υπολογίζει την αποδοτικότητα του σχεδιασμού (D – efficiency). Τέλος, στο τέταρτο και τελευταίο κεφάλαιο αναπτύσσεται η μελέτη περίπτωσης ενός PWO σχεδιασμού με τέσσερις μεταβλητές. Από τις συνολικές εκτελέσεις (θεραπείες) του πλήρους PWO σχεδιασμού με τέσσερις μεταβλητές επιλέγεται ένα πλήθος σχεδιασμών με λιγότερες εκτελέσεις ο καθένας τη φορά και υπολογίζεται η D – αποδοτικότητα τους, με τελικό σκοπό να βρεθεί ο σχεδιασμός με τις λιγότερες εκτελέσεις που πλησιάζει περισσότερο την αποδοτικότητα του πλήρους σχεδιασμού, όπου είναι και η καλύτερη.
Neutronization During Carbon Simmering In Type Ia Supernova Progenitors
Creators: name: Martínez-Rodríguez, Héctor
name: Piro, Anthony L.
name: Schwab, Josiah
name: Badenes, Carles
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: When a Type Ia supernova (SN Ia) progenitor first ignites carbon in its core, it undergoes ${\sim} \,10^{3}-10^{4} \,$yr of convective burning prior to the onset of thermonuclear runaway. This carbon simmering phase is important for setting the thermal profile and composition of the white dwarf. Using the \texttt{MESA} stellar evolution code, we follow this convective burning and examine the production of neutron-rich isotopes. The neutron content of the SN fuel has important consequences for the ensuing nucleosynthesis, and, in particular, for the production of secondary Fe-peak nuclei like Mn and stable Ni. These elements have been observed in the X-ray spectra of SN remnants like Tycho, Kepler, and 3C 397, and their yields can provide valuable insights into the physics of SNe Ia and the properties of their progenitors. We find that weak reactions during simmering can at most generate a neutron excess of ${\approx} \, 3 \times 10^{-4}$. This is ${\approx} \, 8 \times 10^{-4}$ lower than that found in previous studies that do not take the full density and temperature profile of the simmering region into account. Our results imply that the progenitor metallicity is the main contributor to the neutron excess in SN Ia fuel for $Z \gtrsim 1/3 \, Z_{\odot}$. Alternatively, at lower metallicities, this neutron excess provides a floor that should be present in any centrally-ignited SN~Ia scenario.
description: 15 pages, 16 figures, 6 tables, accepted for publication in the ApJ
Ευθύνη παραγωγού από ελαττωματικό προϊόν : νομική & οικονομική ανάλυση
Creators: name: Ξεΐνη, Αμαλία
Publisher: name: Πανεπιστήμιο Πειραιώς
Year: 2023
Subjects: subject: Ευθύνη παραγωγού
subject: Ελαττωματικό προϊόν

description: Αντικείμενο της παρούσας μελέτης είναι η παρουσίαση των νομοθετικών διατάξεων που αφορούν στην ευθύνη του παραγωγού ελαττωματικών προϊόντων σε Ενωσιακό και εθνικό επίπεδο καθώς και οι προϋποθέσεις θεμελίωσης αυτής της ευθύνης τόσο σε επίπεδο νομοθεσίας όσο και σε επίπεδο οικονομικής ανάλυσης του δικαίου (Ο.Α.Δ) με σχετική αναφορά σε παραδείγματα από την εθνική και διεθνή νομολογία και ιδιαίτερη έμφαση στην ευθύνη του παραγωγού στα φαρμακευτικά προϊόντα. Στο πρώτο κεφάλαιο της εργασίας αναλύεται η Ενωσιακή προέλευση της διάταξης 6 του Ν. 2251/1994 με ειδικότερη περιγραφή των εννοιών που αποτελούν τα βασικά στοιχεία θεμελίωσης της ευθύνης του παραγωγού, κατ’ εφαρμογή του ελληνικού εφαρμοστέου πλαισίου. Στο δεύτερο κεφάλαιο παρουσιάζεται η ευθύνη του παραγωγού κατά την Ο.Α.Δ. Η εργασία κλείνει με τα συμπεράσματα που προκύπτουν από την υιοθέτηση της ευρωπαϊκής Οδηγίας 85/374/ΕΟΚ στην ελληνική έννομη τάξη και τον αντίκτυπο της σε κοινωνικοοικονομικό επίπεδο. Τέλος, παρατίθεται παράρτημα με ορισμένα παραδείγματα από την θέση των εθνικών και των ευρωπαϊκών δικαστηρίων με έμφαση στην ευθύνη του παραγωγού από ελαττωματικά φαρμακευτικά προϊόντα.