cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The effect of Collaborative-Filtering based Recommendation Algorithms on Opinion Polarization
Creators: name: Bellina, Alessandro
name: Castellano, Claudio
name: Pineau, Paul
name: Iannelli, Giulio
name: De Marzo, Giordano
Publisher: name: arXiv
Year: 2023
Subjects: subject: Physics and Society (physics.soc-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: A central role in shaping the experience of users online is played by recommendation algorithms. On the one hand they help retrieving content that best suits users taste, but on the other hand they may give rise to the so called "filter bubble" effect, favoring the rise of polarization. In the present paper we study how a user-user collaborative-filtering algorithm affects the behavior of a group of agents repeatedly exposed to it. By means of analytical and numerical techniques we show how the system stationary state depends on the strength of the similarity and popularity biases, quantifying respectively the weight given to the most similar users and to the best rated items. In particular, we derive a phase diagram of the model, where we observe three distinct phases: disorder, consensus and polarization. In the latter users spontaneously split into different groups, each focused on a single item. We identify, at the boundary between the disorder and polarization phases, a region where recommendations are nontrivially personalized without leading to filter bubbles. Finally, we show that our model can reproduce the behavior of users in the online music platform last.fm. This analysis paves the way to a systematic analysis of recommendation algorithms by means of statistical physics methods and opens to the possibility of devising less polarizing recommendation algorithms.
Bogoliubov theory for atom scattering into separate regions
Creators: name: Wasak, T.
name: Szankowski, P.
name: Bücker, R.
name: Chwedenczuk, J.
name: Trippenbach, M.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We review the Bogoliubov theory in the context of recent experiments, where atoms are scattered from a Bose-Einstein Condensate into two well-separated regions. We find the full dynamics of the pair-production process, calculate the first and second order correlation functions and show that the system is ideally number-squeezed. We calculate the Fisher information to show how the entanglement between the atoms from the two regions changes in time. We also provide a simple expression for the lower bound of the useful entanglement in the system in terms of the average number of scattered atoms and the number of modes they occupy. We then apply our theory to a recent "twin-beam" experiment [R. Bücker {\it et al.}, Nat. Phys. {\bf 7}, 608 (2011)]. The only numerical step of our semi-analytical description can be easily solved and does not require implementation of any stochastic methods.
description: 11 pages, 6 figures
Asians & Friends Chicago: The Politics of Interracial Desire in a Gay Friendship Group
Creators: name: Phan, Khoa
Publisher: name: University of Chicago
Year: 2019
Subjects: subject: racial inequality
subject: intimate relationships
subject: Asians & Friends Chicago (AFC)
subject: community gatherings
subject: interracial romantic relationship
subject: sex, gender, and sexuality

description: How is racial inequality reproduced and resisted in relationships of intimacy (friendships, sexual relations, romantic connections)? How does racial inequality operate both through individual negotiations and differentiated stakes, and through collective, idealized group-building? This study explores questions for the relationship between gay Asian men and gay white men, through a case study of Asians & Friends Chicago (AFC), a gay friendship group of gay Asian men and their gay (majority white) friends. The group’s individual stories and interactional dynamics are documented and analyzed through mixed qualitative sociological methods: archival analysis of AFC Archives, participant observation of the group’s interactions at official events and informal gatherings, and in-depth interviews with 24 group members. Through the lens of the sexual fields’ framework, AFC emerges as a field with collective norms and practices that all members respond to: non-sexual friendship, post-racial inclusivity, and prioritizing the Asian-white romantic relationship. These logics are organizational responses to gay Asian men’s low desirability in other sexual fields, and gay white men’s potentially fetishistic desires for them. At the same time, as Asian members and white members enter the field with different stakes, AFC’s organizational logics both attempt to recalibrate these stakes while still repeating similar racial/sexual inequalities outside the group. This social mapping thus explores how resistances to racial inequality and sexual fetishism can potentially reach an organizational (yet uneven) level, as gay men think through their different contexts how to individually and collectively articulate their desires for intimacy and companionship.
On Marginal Deformations and Non-Integrability
Creators: name: Giataganas, Dimitrios
name: Zayas, Leopoldo A. Pando
name: Zoubos, Konstantinos
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Chaotic Dynamics (nlin.CD)
subject: FOS: Physical sciences

description: We study the interplay between a particular marginal deformation of ${\cal N}=4$ super Yang-Mills theory, the $β$ deformation, and integrability in the holographic setting. Using modern methods of analytic non-integrability of Hamiltonian systems, we find that, when the $β$ parameter takes imaginary values, classical string trajectories on the dual background become non-integrable. We expect the same to be true for generic complex $β$ parameter. By exhibiting the Poincaré sections and phase space trajectories for the generic complex $β$ case, we provide numerical evidence of strong sensitivity to initial conditions. Our findings agree with expectations from weak coupling that the complex $β$ deformation is non-integrable and provide a rigorous argument beyond the trial and error approach to non-integrability.
description: 19 pages, 9 figures
Fluctuation of the phase boundary in the six-vertex model with Domain Wall Boundary Conditions: a Monte Carlo study
Creators: name: Lyberg, Ivar
name: Korepin, Vladimir
name: Viti, Jacopo
Publisher: name: arXiv
Year: 2023
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We consider the six-vertex model with Domain Wall Boundary Conditions on a $N\times N$ square lattice. Our main interest is the study of the fluctuations of the extremal lattice path about the arctic curves. We address the problem through Monte Carlo simulations. At $Δ= 0$, the fluctuations of the extremal path along any line parallel to the square diagonal were rigorously proven to follow the Tracy-Widom distribution. We provide strong numerical evidence that this is true also for other values of the anisotropy parameter $Δ$ ($0\leq Δ< 1$). We argue that the typical width of the fluctuations of the extremal path about the arctic curves scales as $N^{1/3}$ and provide a numerical estimate for the parameters of the scaling random variable.
description: 15 pages, 9 figures, revised version: added the study of the third and fourth cumulant. J. Phys. A: Math. Theor. (2023)
title: Проектирование в образовании: моделирование и управление рисками
Creators: name: Каличава, Э.
Publisher: name: Новгородский государственный университет имени Ярослава Мудрого (НовГУ)
Year: 2020

description: В статье рассматриваются варианты моделирования ситуаций с учетом возможных рисков в процессе реализации образовательных программ; поясняется необходимость выявления, классификации и устранения потенциальных рисков как части системы менеджмента качества.
Assessment and rehabilitation in acquired brain injury: The role of social and therapeutic engagement in recovery
Creators: name: Gunn, Sarah
Publisher: name: University of Leicester
Year: 2020
Subjects: Uncategorized

description: Thesis AbstractRehabilitation outcomes following acquired brain injury are affected by a complex mix of variables, including demographics, injury characteristics, post-injury function and intensity and duration of rehabilitation. Assessing key factors and making prognostic judgements is therefore difficult. This thesis aimed to develop a greater understanding of assessment and predictive factors in rehabilitative outcomes following acquired brain injury, particularly focusing on the role of therapeutic and social engagement in rehabilitation.Literature ReviewThe Functional Independence Measure and Functional Assessment Measure is used extensively in UK rehabilitation services and worldwide; however, no recent review has been conducted into its psychometric properties. The current review examined 28 quantitative studies derived from six databases, identifying excellent internal consistency, interrater reliability and criterion validity, and good responsiveness. However, ceiling effects were identified in less functionally-impaired populations, evidence for manualised subscales was unconvincing, and qualitative patient goals are not well-reflected in scoring.Empirical StudyThe research study comprised two investigations. Firstly, the roles of group and individual social engagement and behaviours of concern in acquired brain injury rehabilitation outcomes were explored. Multiple regressions identified that greater group participation predicts better physical recovery, and greater individual therapy participation predicts poorer cognitive recovery; the latter may relate to the typical slower recovery of cognitive function post-injury or to ceiling effects. Individuals exhibiting behaviours of concern showed better mean physical recovery than controls, although their longer mean length of stay in hospital may have contributed. In the second investigation, the convergent validity of the FIM+FAM Social Interaction was evaluated, identifying significant correlations with ecologically-valid markers of engagement (individual therapy and group participation).AppendicesThe appendices provide detail about the empirical study, including the ethical review, key measures used, a methodological critique, and clinical and theoretical implications.
Systems Variability Modeling: A Textual Model Mixing Class and Feature Concepts
Creators: name: Younis, Ola
name: Ghoul, Said
name: Alomari, Mohammad H.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Software Engineering (cs.SE)
subject: FOS: Computer and information sciences

description: System reuse and cost are very important in software product line design area. Developers goal is to increase system reuse and decreasing cost and efforts for building components from scratch for each software configuration. This can be reached by developing Software Product Line (SPL). To handle SPL engineering process, several approaches with several techniques were developed. One of these approaches is called separated approach. It requires separating the commonalities and variability for system components to allow configuration selection based on user defined features. Textual notation-based approaches have been used for their formal syntax and semantics to represent system features and implementations. But these approaches are still weak in mixing features (conceptual level) and classes (physical level) that guarantee smooth and automatic configuration generation for software releases. The absence of methodology supporting the mixing process is a real weakness. In this paper, we enhanced SPL reuse by introducing some meta-features, classified according to their functions. As a first consequence, mixing class and feature concepts is supported in a simple way using class interfaces and inherent features for smooth move from feature model to class model. And as a second consequence, the mixing process is supported by a textual design and implementation methodology, mixing class and feature models by combining their concepts in a single language. The supported configuration generation process is simple, coherent, and complete.
description: 10 pages
Revisiting progenitor-age dependence of type Ia supernova luminosity standardization process
Creators: name: Wang, Junchao
name: Huang, Zhiqi
name: Huang, Lu
Publisher: name: arXiv
Year: 2023
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences
subject: J.2
subject: 85A40

description: Much of the research in supernova cosmology is based on an assumption that the peak luminosity of type Ia supernovae (SNe Ia), after a standardization process, is independent of the galactic environment. A series of recent studies suggested that there is a significant correlation between the standardized luminosity and the progenitor age of SNe Ia. The correlation found in the most recent work by Lee et al. is strong enough to explain the extra dimming of distant SNe Ia and therefore casts doubts on the direct evidence of cosmic acceleration. The present work incorporates the uncertainties of progenitor ages, which were ignored in Lee et al., into a fully Bayesian inference framework. We find a weaker dependence of supernova standardized luminosity on the progenitor age, but the detection of correlation remains significant (3.5$σ$). Assuming that such correlation can be extended to high redshift and applying it to the Pantheon SN Ia data set, we confirm that when the Hubble residual does not include intrinsic scatter, the age-bias could be the primary cause of the observed extra dimming of distant SNe Ia. Furthermore, we use the PAge formalism, which is a good approximation to many dark energy and modified gravity models, to do a model comparison. We find that if intrinsic scatter is included in the Hubble residual, the Lambda cold dark matter model remains a good fit. However, in a scenario without intrinsic scatter, the Lambda cold dark matter model faces a challenge.
description: 8 pages, 6 figures, 2 tables. Published in SCPMA
Optimisation via encodings: a renormalisation group perspective
Creators: name: Klemm, Konstantin
name: Mehta, Anita
name: Stadler, Peter F.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Artificial Intelligence (cs.AI)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Neural and Evolutionary Computing (cs.NE)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: Difficult, in particular NP-complete, optimization problems are traditionally solved approximately using search heuristics. These are usually slowed down by the rugged landscapes encountered, because local minima arrest the search process. Cover-encoding maps were devised to circumvent this problem by transforming the original landscape to one that is free of local minima and enriched in near-optimal solutions. By definition, these involve the mapping of the original (larger) search space into smaller subspaces, by processes that typically amount to a form of coarse-graining. In this paper, we explore the details of this coarse-graining using formal arguments, as well as concrete examples of cover-encoding maps, that are investigated analytically as well as computationally. Our results strongly suggest that the coarse-graining involved in cover-encoding maps bears a strong resemblance to that encountered in renormalisation group schemes. Given the apparently disparate nature of these two formalisms, these strong similarities are rather startling, and suggest deep mathematical underpinnings that await further exploration.
description: 21 pages, 4 figures
title: Together, Our Voices Will Strengthen the Weaving: Using Autoethnography and Narrative Inquiry to Indigenize Sense of Belonging in Higher Education
Creators: name: Isaacs, Devon S.
Publisher: name: Utah State University
Year: 2022

description: Native American students in higher education are often asked to find a sense of belonging in places and spaces that do not reflect their cultures or worldviews. This can lead to isolation and a feeling of having to choose between themselves and their identities as Indigenous peoples. This contributes to poorer mental health, loss of well-being, and decreased academic success. The purpose of this study was to ask seven Native American participants how they defined sense of belonging from their own worldviews. Participants were also asked about spaces and places in higher education that helped or did not help them belong, and how this affected their mental health, well-being, and ability to succeed in the university setting. Using a metaphor of a Cherokee double-walled basket, we drew from our collective stories to define belonging in the following ways: connection, safety, acknowledgment, respect, presence, purpose, and growth. These themes became a model of Indigenized belonging called “Having the Spirit in the Circle”. Two other key themes that affected belonging were gatekeepers and way-makers. Gatekeepers in higher education created barriers to success and way-makers decreased barriers. What we learned together will be used to inform universities about ways they can change current academic success structures to promote belonging that aligns with Indigenous ways of knowing and being and to help Native American students succeed.
Biologic: Gene circuits and feedback in an introductory physics sequence for biology and premedical students
Creators: name: Cahn, S. B.
name: Mochrie, S. G. J.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Physics Education (physics.ed-ph)
subject: Molecular Networks (q-bio.MN)
subject: FOS: Physical sciences
subject: FOS: Biological sciences

description: Two synthetic gene circuits -- the genetic toggle switch and the repressilator -- are analyzed quantitatively and discussed in the context of an educational module on gene circuits and feedback that constitutes the final topic of a year-long introductory physics sequence, aimed at biology and premedical undergraduate students. The genetic toggle switch consists of two genes, each of whose protein product represses the other's expression, while the repressilator consists of three genes, each of whose protein product represses the next gene's expression. Analytic, numerical, and electronic treatments of the genetic toggle switch shows that this gene circuit realizes bistability. A simplified treatment of the repressilator reveals that this circuit can realize sustained oscillations. In both cases, a "phase diagram" is obtained, that specifies the region of parameter space in which bistability or oscillatory behavior, respectively, occurs.
title: Η εξέλιξη των P&I CLUBS: Ασφαλιστικές καλύψεις, αλληλασφάλιση, αντασφάλιση
title: The evolution of P&I CLUBS: Insurance coverage, mutual insurance, reinsurance
titleType: AlternativeTitle
Creators: name: Βουκελάτου, Ευθαλία Στεφανία
Publisher: name: Πανεπιστήμιο Δυτικής Αττικής
Year: 2022
Subjects: Θαλάσσια ασφάλιση
Αλληλασφαλιστικοί οργανισμοί
Αντασφάλιση
P&I Clubs
Protection & Indemnity Clubs
Ναυτική ασφάλιση

description: Η εργασία αυτή φιλοδοξεί να συμβάλλει στην κατανόηση της λειτουργίας των αλληλασφαλιστικών οργανισμών Προστασίας & Αποζημίωσης (P&IClubs), παρουσιάζοντας αναλυτικά τη δομή και τους κανονισμούς τους, καθώς και τις προσφερόμενες στα μέλη βασικές ασφαλιστικές καλύψεις από τους αλληλασφαλιστικούς οργανισμούς. Θα αναλυθεί η έννοια της θαλάσσιας αντασφάλισης, προκειμένου να δοθεί εξήγηση στο ζήτημα της ασφαλιστικής κάλυψης ιδιαίτερα των λεγόμενων καταστροφικών κινδύνων και θα μελετηθεί η πολιτική της αντασφάλισης σε σχέση με την επιβίωση και την λειτουργία των σύγχρονων P&I Clubs. Στο πλαίσιο αυτό, πραγματοποιήθηκε ανασκόπηση βιβλιογραφίας και συλλέχθηκαν στοιχεία για να ερευνηθούν οι έννοιες των βασικών ασφαλιστικών καλύψεων, η σχέση του ασφαλιστή με τον αντασφαλιστή στην προσπάθεια αντιστάθμισης του βάρους από την καταβολή ποσών προς κάλυψη των ζημιών των μελών. Τα συμπεράσματα της παρούσας εργασίας επιβεβαιώνουν ότι μια υγιής αντασφαλιστική αγορά, με τη διασπορά των καλύψεων που αναλαμβάνει σε μεγάλο γεωγραφικό εύρος, έχει μεγάλη συμβολή στη διασφάλιση της φερεγγυότητας των ασφαλιστικών εταιριών-Ομίλων. Η διατριβή ολοκληρώνεται με τις επιπτώσεις και τα μελλοντικά ερευνητικά πεδία
Instantaneous Bethe-Salpeter Approach to Pseudoscalar Mesons
Creators: name: Lucha, Wolfgang
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Light pseudoscalar mesons are Janus-type particles: Within quantum chromodynamics, they must be described as bound states of its fundamental degrees of freedom and as the (pseudo-) Goldstone bosons of its spontaneously broken chiral symmetry. This janiform nature of pions and kaons may be easily accommodated by the Bethe-Salpeter formalism in its instantaneous limit: Starting from the general behaviour of the Bethe-Salpeter solutions for light pseudoscalar mesons at large Euclidean momenta, we provide the exact relationship between the solutions of our bound-state equation and the underlying interactions, boiled down to a configuration-space potential depending on the interquark distance: the potential exhibits a logarithmically softened Coulomb singularity at the origin and, at large interquark distances, rises beyond bounds for massless quarks but approaches a non-positive finite limit for too heavy quarks.
description: 2 pages, 2 figures, contributed to the European Physical Society Conference on High Energy Physics - EPS-HEP2013, 18-24 July 2013, Stockholm, Sweden
Plasma channels under filamentation of infrared and ultraviolet double femtosecond laser pulses
Creators: name: Ionin, A. A.
name: Kudryashov, S. I.
name: Mokrousova, D. V.
name: Seleznev, L. V.
name: Sinitsyn, D. V.
name: Sunchugasheva, E. S.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: An influence of plasma channel created by a filament of focused UV or IR femtosecond laser pulse (λ=248 nm or 740 nm) on characteristics of other plasma channel formed by a femtosecond pulse at the same wavelength following the first one with varied nanosecond time delay was experimentally studied. A dependence of optical transparency of the first channel and plasma density of the second channel on the time delay was demonstrated to be quite different for such a double UV and IR femtosecond pulses.
description: 5 pages, 3 figures
Enhanced Spin-polarization via Partial Ge1-dimerization as the Driving Force of the 2$\times$2$\times$2 CDW in FeGe
Creators: name: Wang, Yilin
Publisher: name: arXiv
Year: 2023
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: A $2\times2\times2$ charge density wave (CDW) was recently observed deep inside the antiferromagnetic phase of a Kagome metal FeGe. A key question is whether the CDW in FeGe is driven by its electronic correlation and magnetism. Here, we address this problem using density functional theory and its combination with $U$ as well as dynamical mean-field theory. Our calculations show that large dimerization ($\sim 1.3 \overset{\lower.5em\circ}{\mathrm{A}}$) of Ge1-sites along $c$-axis will enhance electronic correlation of the Fe-$3d$ orbitals and, as a result, it enhances the spin-polarization and saves more magnetic exchange energies. We find that the balance between magnetic energy saving and structural energy cost via partially dimerizing Ge1-sites in an enlarged superstructure, could induce a new local minimum in total energies. The response to the large partial Ge1-dimerization will induce additional small modulations ($<0.05 \overset{\lower.5em\circ}{\mathrm{A}}$) of other sites in the Kagome and honeycomb layers, which further reduces the total energy and leads to a stable $2\times 2\times 2$ CDW ground state in FeGe. Our results are in good agreement with the existing experiments and reveal a novel CDW mechanism driven by the interplay of structure, electronic correlation and magnetism.
description: 4 pages and 4 figures in the main text; 2 pages and 1 figure in the Supplementary Materials
Convexity of parabolic subgroups in Artin groups
Creators: name: Charney, Ruth
name: Paris, Luis
Publisher: name: arXiv
Year: 2014
Subjects: subject: Group Theory (math.GR)
subject: FOS: Mathematics

description: We prove that any standard parabolic subgroup of any Artin group is convex with respect to the standard generating set.
title: Κλιματική κρίση και επισιτιστική ασφάλεια στην Ευρώπη
title: Climate crisis and food security in Europe
titleType: AlternativeTitle
Creators: name: Τσαπόγας, Χρήστος
Publisher: name: Πανεπιστήμιο Δυτικής Αττικής
Year: 2023
Subjects: Κλιματική κρίση
Κλιματική αλλαγή
Υπερθέρμανση του πλανήτη
Επισιτιστική ασφάλεια
Επισιτιστική ανασφάλεια
Διαθεσιμότητα τροφίμων
Ευρώπη

description: Η μέση παγκόσμια θερμοκρασία έχει αυξηθεί κατά περίπου 1°C, σε σχέση με την προβιομηχανική περίοδο, ενώ είναι πολύ πιθανό ότι θα ξεπεράσει τους 1,5°C – 2°C, μέχρι το τέλος του τρέχοντος αιώνα. Η κλιματική κρίση, που οδηγεί σταδιακά στην κλιματική αλλαγή, επηρεάζει όλες τις διαστάσεις της επισιτιστικής ασφάλειας, δρώντας ως πολλαπλασιαστής πιέσεων, ενώ οι παρατηρηθείσες και προβλεπόμενες επιπτώσεις είναι, κατά κύριο λόγο, αρνητικές. Όσο αυξάνεται η παγκόσμια θέρμανση, τόσο περισσότεροι και πιο σύνθετοι είναι οι κίνδυνοι που εγκυμονούνται για την επισιτιστική ασφάλεια. Η κλιματική κρίση ενέχει κινδύνους για τη διαθεσιμότητα των τροφίμων, επηρεάζοντας την παραγωγικότητα του αγροτικού τομέα, για την πρόσβαση των πληθυσμών σε επαρκή τρόφιμα, επηρεάζοντας τα εισοδήματα, τις τιμές των τροφίμων και τα μεταναστευτικά μοτίβα, για την αξιοποίηση των τροφίμων, εγκυμονώντας κινδύνους για την ασφάλεια των τροφίμων και του νερού, καθώς και για τη σταθερότητα της παροχής τροφίμων, αυξάνοντας τη συχνότητα και την ένταση των ακραίων καιρικών φαινομένων και των φυσικών καταστροφών. Η Ευρώπη χαρακτηρίζεται από καλά επίπεδα επισιτιστικής ασφάλειας, συγκριτικά με τις περισσότερες ηπείρους. Παρ’ όλα αυτά, δεδομένου ότι για την επίτευξη της επισιτιστικής ασφάλειας, θα πρέπει να πληρούνται οι προϋποθέσεις όλων των διαστάσεών της ταυτοχρόνως, υπάρχουν σημαντικά ζητήματα που αφορούν την τρέχουσα και μελλοντική επισιτιστική ασφάλεια των πληθυσμών της Ευρώπης, ενώ παράλληλα οι διάφοροι κίνδυνοι δεν είναι ίσα κατανεμημένοι στις διάφορες περιοχές, σε παγκόσμια κλίμακα, αλλά και εντός της ευρωπαϊκής ηπείρου. Η άμεση ανάπτυξη μηχανισμών μετριασμού και προσαρμογής στην κλιματική αλλαγή είναι καίριας σημασίας για την προστασία της επισιτιστικής ασφάλειας και της Δημόσιας Υγείας γενικότερα. Δεδομένου ότι ο κλιματικός κίνδυνος είναι διασυνοριακός, οι δράσεις θα πρέπει να λαμβάνουν χώρα σε παγκόσμια κλίμακα.
Attraction versus repulsion between doublons or holons in Mott-Hubbard systems
Creators: name: Queisser, Friedemann
name: Schaller, Gernot
name: Schützhold, Ralf
Publisher: name: arXiv
Year: 2023
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: For the Mott insulator state of the Fermi-Hubbard model in the strong-coupling limit, we study the interaction between quasi-particles in the form of doublons and holons. Comparing different methods -- the hierarchy of correlations, strong-coupling perturbation theory, and exact analytic solutions for the Hubbard tetramer -- we find an effective interaction between doublons and/or holons to linear order in the hopping strength $T$ which can display attractive as well as repulsive contributions, depending on the involved momenta. Finally, we speculate about the implications of our findings for high-temperature superconductivity.
Quasimodal expansion of electromagnetic fields in open two-dimensionnal structures
Creators: name: Vial, Benjamin
name: Zolla, Frédéric
name: Nicolet, André
name: Commandré, Mireille
Publisher: name: arXiv
Year: 2013
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: A quasimodal expansion method (QMEM) is developed to model and understand the scattering properties of arbitrary shaped two-dimensional (2-D) open structures. In contrast with the bounded case which have only discrete spectrum (real in the lossless media case), open resonators show a continuous spectrum composed of radiation modes and may also be characterized by resonances associated to complex eigenvalues (quasimodes). The use of a complex change of coordinates to build Perfectly Matched Layers (PMLs) allows the numerical computation of those quasimodes and of approximate radiation modes. Unfortunately, the transformed operator at stake is no longer self-adjoint, and classical modal expansion fails. To cope with this issue, we consider an adjoint eigenvalue problem which eigenvectors are bi-orthogonal to the eigenvectors of the initial problem. The scattered field is expanded on this complete set of modes leading to a reduced order model of the initial problem. The different contributions of the eigenmodes to the scattered field unambiguously appears through the modal coefficients, allowing us to analyze how a given mode is excited when changing incidence parameters. This gives new physical insights to the spectral properties of different open structures such as nanoparticles and diffraction gratings. Moreover, the QMEM proves to be extremely efficient for the computation of Local Density Of States (LDOS).
Damage detection via shortest path network sampling
Creators: name: Ciulla, Fabio
name: Perra, Nicola
name: Baronchelli, Andrea
name: Vespignani, Alessandro
Publisher: name: arXiv
Year: 2014
Subjects: subject: Physics and Society (physics.soc-ph)
subject: FOS: Physical sciences

description: Large networked systems are constantly exposed to local damages and failures that can alter their functionality. The knowledge of the structure of these systems is however often derived through sampling strategies whose effectiveness at damage detection has not been thoroughly investigated so far. Here we study the performance of shortest path sampling for damage detection in large scale networks. We define appropriate metrics to characterize the sampling process before and after the damage, providing statistical estimates for the status of nodes (damaged, not-damaged). The proposed methodology is flexible and allows tuning the trade-off between the accuracy of the damage detection and the number of probes used to sample the network. We test and measure the efficiency of our approach considering both synthetic and real networks data. Remarkably, in all the systems studied the number of correctly identified damaged nodes exceeds the number false positives allowing to uncover precisely the damage.
Resource-efficient high-dimensional entanglement detection via symmetric projections
Creators: name: Morelli, Simon
name: Huber, Marcus
name: Tavakoli, Armin
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We introduce two families of criteria for detecting and quantifying the entanglement of a bipartite quantum state of arbitrary local dimension. The first is based on measurements in mutually unbiased bases and the second is based on equiangular measurements. Both criteria give a qualitative result in terms of the state's entanglement dimension and a quantitative result in terms of its fidelity with the maximally entangled state. The criteria are universally applicable since no assumptions on the state are required. Moreover, the experimenter can control the trade-off between resource-efficiency and noise-tolerance by selecting the number of measurements performed. For paradigmatic noise models, we show that only a small number of measurements are necessary to achieve nearly-optimal detection in any dimension. The number of global product projections scales only linearly in the local dimension, thus paving the way for detection and quantification of very high-dimensional entanglement.
description: 6+2 pages
Love Numbers for Rotating Black Holes in Higher Dimensions
Creators: name: Rodriguez, Maria J.
name: Santoni, Luca
name: Solomon, Adam R.
name: Temoche, Luis Fernando
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We compute the tidal Love numbers and static response coefficients associated to several rotating black holes in higher dimensions, including Myers-Perry black holes, black rings, and black strings. These coefficients exhibit a rich and complex structure as a function of the black hole parameters and multipoles. Our results agree in limiting cases with known and new expressions for various lower-dimensional black holes. In particular, we provide an alternative approach to the computation of the static response of Kerr black holes as a limiting case of the boosted black string.
description: 23+5 pages, 2 figures. v2: minor updates
Multiscale characterisation of neural heterogeneity in psychiatric disorders
Creators: name: SEGAL, ASHLEA PETA
Publisher: name: Monash University
Year: 2023
Subjects: classificationCode: 320904
subject: Computational neuroscience (incl. mathematical neuroscience and theoretical neuroscience)
classificationCode: 320221
subject: Psychiatry (incl. psychotherapy)

description: The diagnosis of mental illness is notoriously complicated. On the one hand, people with the same diagnosis show tremendous diversity in symptoms; on the other hand, people with different diagnoses often share similar symptoms. This thesis developed new analysis techniques to map brain changes in individual patients to identify the neurobiological correlates of similarities and differences within and between six different psychiatric disorders. The findings offer important insights into the validity of existing diagnostic schemes, potential treatment targets and disease mechanisms, and individual variability in mental illness.
title: У истоков среднего специального педагогического образования Минска: штрихи к портретам студентов и преподавателей Минского Белорусского педагогического техникума
Creators: name: Наумов, В.
Publisher: name: Новгородский государственный университет имени Ярослава Мудрого (НовГУ)
Year: 2020

description: В статье рассматриваются различные аспекты жизненных и творческих биографий выдающихся преподавателей и ученых, студентов, которые в 1920-е гг. работали или учились в Минском Белорусском педагогическом техникуме. Объект исследования – биографии Я. Коласа, М. Н. Пиотуховича, М. А. Громыко, П. Ф. Глебки
и других личностей, которые внесли значительный вклад в становление культуры Советской Беларуси. Цель исследования – выявление на основе впервые введенных в научный оборот документов сущностных характеристик функционирования Минского Белорусского педагогического техникума в контексте общественно-политической, социально-экономической, национально-культурной жизни БССР 1920-х гг.
Приведенные в статье данные позволяют дополнить биографии представителей белорусской интеллигенции, которые заложили основу системы подготовки высококвалифицированных кадров для различных сфер. Результаты работы могут быть использованы при организации учебного и воспитательного процесса в учреждениях образования, для проведения профориентационной работы. Многие характеристики
профессиональной деятельности преподавателей и студентов Минского Белорусского педагогического техникума анализируются впервые.
Proof of the Gour-Wallach conjecture
Creators: name: Chen, Lin
name: Djokovic, Dragomir Z.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The absolute value of the hyperdeterminant of four qubits is a useful measure of genuine entanglement. We prove a recent conjecture of Gour and Wallach describing the pure maximally entangled four-qubit states with respect to this measure.
description: 6 pages, minor revision
title: Effects of Obesity on Knee Extensor Structure, Function, and Gait: A Systematic Review and Meta-Analysis
Creators: name: Vakula, Michael N.
Publisher: name: Utah State University
Year: 2022

description: Obesity is a common, costly, and critical disease that increases the risk of disability and premature death. Most commonly, obesity is caused by an increased consumption of energy dense foods and decreased time spent being physically active. The greater weight with obesity interrupts normal musculoskeletal function which can lead to physical adaptations such as decreased lower-extremity muscle strength and abnormal walking patterns, both of which are among top risk factors for falls in older individuals. However, the effects of obesity on walking and lower-extremity muscle strength have not previously been examined by incorporating the results of all existing studies in a comprehensive systematic review and meta-analysis. Therefore, the purpose of this dissertation was to (1) determine the effect of obesity on measures of walking in adults, and to (2) determine the effect of obesity on knee extensor strength, muscle size, and muscle quality in children, adolescents, adults and older adults. In the first study, there were 47 studies included in the systematic review and 44 in the meta-analyses. Study two included 35 studies in the systematic review and 29 in the meta-analyses. The results suggest that (1) obesity reduces self-selected walking speed and step length, but increases step width and the amount of time spent with both feet in contact with the ground, and (2) obesity increases absolute maximal measures of knee extensor strength and muscle size, but decreases relative maximal measures of knee extensor strength and muscle quality. However, the effect of obesity on knee extensor size, quality, and strength appears to diminish with age. The results of this dissertation will improve our understanding of how obesity influences walking and knee extensor function, which will allow the design of better treatments for those suffering from obesity as well as a basis of knowledge to guide researchers going forward.
Generating large disordered stealthy hyperuniform systems with ultra-high accuracy to determine their physical properties
Creators: name: Morse, Peter K.
name: Kim, Jaeuk
name: Steinhardt, Paul J.
name: Torquato, Salvatore
Publisher: name: arXiv
Year: 2023
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: Hyperuniform many-particle systems are characterized by a structure factor $S({\mathbf{k}})$ that is precisely zero as $|\mathbf{k}|\rightarrow0$; and stealthy hyperuniform systems have $S({\mathbf{k}})=0$ for the finite range $0 < |{\mathbf{k}}| \le K$, called the "exclusion region." Through a process of collective-coordinate optimization, energy-minimizing disordered stealthy hyperuniform systems of moderate size have been made to high accuracy, and their novel physical properties have shown great promise. However, minimizing $S(\mathbf{k})$ in the exclusion region is computationally intensive as the system size becomes large. In this Letter, we present an improved methodology to generate such states using double-double precision calculations on GPUs that reduces the deviations from zero within the exclusion region by a factor of approximately $10^{30}$ for systems sizes more than an order of magnitude larger. We further show that this ultra-high accuracy is required to draw conclusions about their corresponding characteristics, such as the nature of the associated energy landscape and the presence or absence of Anderson localization, which might be masked, even when deviations are relatively small.
description: 7 pages, 3 figures
Was bedeutet lutherische Identität in der konfessionellen und geistesgeschichtlichen Lage Ungarns?
Creators: name: Szabó, Lajos
Publisher: name: Lutherische Kirche in der Welt
Year: 1970

description: Lutherische Kirche in der Welt, Bd. 43 (1996): Lutherische Kirche in der Welt, Band 43
title: Формирование коммуникативной компетенции младших школьников на уроках русского языка и литературного чтения
Creators: name: Фомина, Я.
Publisher: name: Новгородский государственный университет имени Ярослава Мудрого (НовГУ)
Year: 2020

description: В работе представлен исторический аспект развития понятия «коммуникативная компетенция»; рассмотрены психолого-педагогические особенности развития детей младшего школьного возраста и их связь с развитием умения общаться; описаны методы и приемы, позволяющие более полно сформировать у детей младшего
школьного возраста навыки коммуникации; а также представлены результаты диагностики и образовательной деятельности, которая выстроена по результатам диагностики.
title: Simulated Use of the Exponential Polynomial/Maximum Likelihood Technique in Developing Suitability of Use Functions for Fish Habitat
Creators: name: Voos, Kenneth A.
Publisher: name: Utah State University
Year: 1981

description: The purpose of this paper is to present a new methodology for producing fish habitat suitability at use functions. The suitability functions are relative measures of the voluntary or involuntary preference for combinations of the values of environmental attributes by a fish species and age class. This suitability function is used to determine the relative usability of a physical stream environment as fish habitat.
A generalized function form, exponential polynomials, was selected for the development of these suitability of use functions. The maximum likelihood technique was used for function parameter solution. Derivation of the suitability functions was simulated for several stream environments having variable fish densities.
Optimal Virtual Tube Planning and Control for Swarm Robotics
Creators: name: Mao, Pengda
name: Fu, Rao
name: Quan, Quan
Publisher: name: arXiv
Year: 2023
Subjects: subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: This paper presents a novel method for efficiently solving a trajectory planning problem for swarm robotics in cluttered environments. Recent research has demonstrated high success rates in real-time local trajectory planning for swarm robotics in cluttered environments, but optimizing trajectories for each robot is still computationally expensive, with a computational complexity from $O\left(k\left(n_t,\varepsilon \right)n_t^2\right)$ to $ O\left(k\left(n_t,\varepsilon \right)n_t^3\right)$ where $n_t$ is the number of parameters in the parameterized trajectory, $\varepsilon$ is precision and $k\left(n_t,\varepsilon \right)$ is the number of iterations with respect to $n_t$ and $\varepsilon$. Furthermore, the swarm is difficult to move as a group. To address this issue, we define and then construct the optimal virtual tube, which includes infinite optimal trajectories. Under certain conditions, any optimal trajectory in the optimal virtual tube can be expressed as a convex combination of a finite number of optimal trajectories, with a computational complexity of $O\left(n_t\right)$. Afterward, a hierarchical approach including a planning method of the optimal virtual tube with minimizing energy and distributed model predictive control is proposed. In simulations and experiments, the proposed approach is validated and its effectiveness over other methods is demonstrated through comparison.
Origin of magnetar-scale crustal field in PSR J1852+0040 and "frozen" magnetars
Creators: name: Popov, S. B.
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We discuss the origin of strong crustal magnetic field in one of central compact objects (CCOs) --- a neutron star PSR J1852+0040 in the supernova remnant Kes 79. Taking into account its relatively long present day spin period we conclude that the field could not be generated via a dynamo mechanism. If this neutron star indeed is a magnetar with field submerged during a strong fall-back episode, then it argues against the dynamo field origin in magnetars. Otherwise, Kes 79 is not a close relative of normal magnetars. A discovery of an anti-magnetar with a millisecond period and strong crustal field identifiable, for example, due to large pulse fraction, would be the proof of the dynamo field origin. Existence of such sources is in correspondence with the present standard picture of neutron star unification. However, the fraction of magnetars with submerged fields can be small --- few percent of the total number of CCOs.
description: 4 pages, accepted for publication in PASA
title: Исследовательская и проектная деятельность студенческого научного общества ГПОУ ТО ДПК «Новое поколение»
Creators: name: Харихонов, А.
name: Евтехова, О.
Publisher: name: Новгородский государственный университет имени Ярослава Мудрого (НовГУ)
Year: 2020

description: Статья посвящена способам формирования ключевых компетенций у студентов средних профессиональных образовательных учреждений в рамках работы студенческого научного общества. Рассмотрен метод проектов как современная педагогическая технология, используемая для организации научно-исследовательской
деятельности студентов.
Distribution of Cracks in a Chain of Atoms at Low Temperature
Creators: name: Jansen, Sabine
name: König, Wolfgang
name: Schmidt, Bernd
name: Theil, Florian
Publisher: name: Technische Universität Berlin
Year: 2021
Subjects: subject: 500 Naturwissenschaften und Mathematik::510 Mathematik::510 Mathematik
subject: many-body system
subject: low temperature
subject: periodic lattice
subject: Lennard–Jones type
subject: thermodynamics

description: We consider a one-dimensional classical many-body system with interaction potential of Lennard–Jones type in the thermodynamic limit at low temperature 1/β∈(0,∞). The ground state is a periodic lattice. We show that when the density is strictly smaller than the density of the ground state lattice, the system with N particles fills space by alternating approximately crystalline domains (clusters) with empty domains (voids) due to cracked bonds. The number of domains is of the order of Nexp(−βesurf/2) with esurf>0 a surface energy. For the proof, the system is mapped to an effective model, which is a low-density lattice gas of defects. The results require conditions on the interactions between defects. We succeed in verifying these conditions for next-nearest neighbor interactions, applying recently derived uniform estimates of correlations.