cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Monopoles and clusters
Creators: name: Bielawski, Roger
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Differential Geometry (math.DG)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We define and study certain hyperkaehler manifolds which capture the asymptotic behaviour of the SU(2)-monopole metric in regions where monopoles break down into monopoles of lower charges. The rate at which these new metrics approximate the monopole metric is exponential, as for the Gibbons-Manton metric.
description: v2.: relation to calorons mentioned; added explanations
Οι αποφάσεις επιλογής τουριστικών προορισμών με βάση τη θεωρία της Κανονιστικής Εστίασης (Regulatory Focus)
Creators: name: Μητσόπουλος, Μάριος
Publisher: name: Πανεπιστήμιο Πειραιώς
Year: 2021
Subjects: subject: Θεωρία Κανονιστικής Εστίασης
subject: Regulatory Focus
subject: Αντιλαμβανόμενη επικινδυνότητα
subject: Τουρισμός
subject: Επιλογή προορισμού

description: Σκοπός της παρούσας διπλωματικής εργασίας είναι να εξετάσει αν η Κανονιστική Εστίαση (Regulatory Focus) ενός ατόμου, μπορεί να επηρεάσει τη διαδικασία επιλογής τουριστικού προορισμού. Στο πρώτο μέρος της εργασίας ασχολούμαστε με το θεωρητικό πλαίσιο. Αρχικά, εξετάζονται τα τουριστικά κίνητρα και η αντιλαμβανόμενη επικινδυνότητα, που μπορεί να λειτουργήσει ως αποτρεπτικός παράγοντας στην επιλογή ενός προορισμού, καθώς επίσης και οι παράγοντες που την επηρεάζουν. Στη συνέχεια, αναλύεται η θεωρία Κανονιστικής Εστίασης, δίνοντας ιδιαίτερη έμφαση στην καταναλωτική συμπεριφορά ατόμων με διαφορετική εστίαση. Στο δεύτερο και πρακτικό μέρος η διπλωματική ασχολείται με την ανάλυση του ερωτηματολογίου που μοιράστηκε το καλοκαίρι του 2019 σε Έλληνες ταξιδιώτες, στους οποίους δόθηκε η επιλογή να επιλέξουν ανάμεσα σε δυο προορισμούς (Ιταλία και Αίγυπτος), αφού πρώτα απαντήσουν σε ερωτήσεις που αφορούσαν την επικινδυνότητα των δυο αυτών προορισμών. Στη συνέχεια κλήθηκαν να απαντήσουν σε ερωτήσεις που αφορούσαν την κανονιστική τους εστίαση, ώστε να μπορέσουν να κατηγοριοποιηθούν αναλόγως. Τα συμπεράσματα της έρευνας, καθώς και τυχόν προτάσεις που προέκυψαν, παρουσιάζονται στο τελευταίο κεφάλαιο της εργασίας.
The Age of the Universe with Globular Clusters: Reducing Systematic Uncertainties
Creators: name: Valcin, David
name: Jimenez, Raul
name: Verde, Licia
name: Bernal, Jose Luis
name: Wandelt, Benjamin D.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The dominant systematic uncertainty in the age determination of galactic globular clusters is the depth of the convection envelope of the stars. This parameter is partially degenerate with metallicity which is in turn degenerate with age. However, if the metal content, distance and extinction are known, the position and morphology of the red giant branch in a color-magnitude diagram are mostly sensitive to the value of the depth of the convective envelope. Therefore, using external, precise metallicity determinations this degeneracy and thus the systematic error in age, can be reduced. Alternatively, the morphology of the red giant branch of globular clusters color magnitude diagram can also be used to achieve the same. We demonstrate that globular cluster red giant branches are well fitted by values of the depth of the convection envelope consistent with those obtained for the Sun and this finding is robust to the adopted treatment of the stellar physics. With these findings, the uncertainty in the depth of the convection envelope is no longer the dominant contribution to the systematic error in the age determination of the oldest globular clusters, reducing it from $0.5$ to $0.23$ or $0.33$ Gyr, depending on the methodology adopted: i.e., whether resorting to external data (spectroscopic metallicity determinations) or relying solely on the morphology of the clusters's color-magnitude diagrams. This results in an age of the Universe $t_{\rm U}=13.5^{+0.16}_{-0.14} {\rm (stat.)} \pm 0.23(0.33) ({\rm sys.})$ at 68\% confidence level, accounting for the formation time of globular clusters and its uncertainty. An uncertainty of 0.27(0.36) Gyr if added in quadrature. This agrees well with $13.8 \pm 0.02$ Gyr, the cosmological model-dependent value inferred by the Planck mission assuming the $Λ$CDM model.
description: Matches accepted version to JCAP. New version includes a new appendix comparing our independently determined distances to GC to those of GAIA DR3; we find excellent agreement
Πολιτικές τιμολόγησης & μάρκετινγκ - Η περίπτωση του τουρισμού
Creators: name: Παπαευσταθίου, Νικόλαος
Publisher: name: Πανεπιστήμιο Πειραιώς
Year: 2021
Subjects: subject: Τιμή
subject: Τιμολόγηση
subject: Τουρισμός
subject: Πολιτικές τιμολόγησης
subject: Marketing
subject: FOS: Economics and business

description: Η τιμή είναι η μόνη παράμετρος του μείγματος μάρκετινγκ που προσφέρει έσοδα στην επιχείρηση, όλες οι υπόλοιπες συνεπάγονται κόστος, γι΄αυτό παίζει κύριο ρόλο στην επιβίωση, στην εδραίωση και την κυριαρχία της επιχείρησης στην αγορά. Η απόφαση για τη διαμόρφωσή της δεν μπορεί να είναι απόφαση ενός ανθρώπου, καθώς δεν είναι ούτε απλή ως διαδικασία, ούτε αυτονόητη. Σειρά ενδο-επιχειρησιακών και εξω-επιχειρησιακών παραγόντων έρχονται να επηρεάσουν την τελική απόφαση που θα πρέπει να κινηθεί στο πλαίσιο μίας ή περισσοτέρων πολιτικών τιμολόγησης και να επιδιωχθεί μέσα από πλειάδα στρατηγικών επιλογών. Η πολυπλοκότητα και η συνθετότητα του παραπάνω τοπίου επιτείνεται απο την αλματώδη πρόοδο της τεχνολογίας, των αναλυτικών της εργαλείων και των επιλογών που αυτά προσφέρουν. Η οξυμένη ανταγωνιστικότητα της αγοράς μας θυμίζει διαρκώς πως τα περιθώρια για λάθη και για αστοχίες διαρκώς στενεύουν και η περαιτέρω «επιστημονικοποίηση» της επιλογής ως προς την τιμολόγηση και την τιμή είναι μονόδρομος.
Simplifying Continuous-Time Quantum Walks on Dynamic Graphs
Creators: name: Herrman, Rebekah
name: Wong, Thomas G.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: Combinatorics (math.CO)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: A continuous-time quantum walk on a dynamic graph evolves by Schrödinger's equation with a sequence of Hamiltonians encoding the edges of the graph. This process is universal for quantum computing, but in general, the dynamic graph that implements a quantum circuit can be quite complicated. In this paper, we give six scenarios under which a dynamic graph can be simplified, and they exploit commuting graphs, identical graphs, perfect state transfer, complementary graphs, isolated vertices, and uniform mixing on the hypercube. As examples, we simplify dynamic graphs, in some instances allowing single-qubit gates to be implemented in parallel.
Non-equilibrium charge noise and dephasing from a spin-incoherent Luttinger liquid
Creators: name: Fiete, Gregory A.
name: Kindermann, Markus
Publisher: name: arXiv
Year: 2006
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We theoretically investigate the charge noise and dephasing in a metallic device in close proximity to a spin incoherent Luttinger liquid with a small but finite current. The frequency dependence of the charge noise exhibits a loss of frequency peaks corresponding to the $2k_F$ part of the density correlations in the electron liquid when the temperature $T$ is increased from values below the magnetic exchange energy $J$ of the electron gas to values above it. The dephasing rate in a nearby metallic nanostructure also shows a cross-over for $T \sim J$ and may exhibit a non-monotonic temperature dependence. For a range of temperatures the dephasing rate {\em decreases} with increasing temperatures. The proposed experiments provide a convenient approach to probe the spin-incoherent Luttinger liquid and should be implementable in a wide variety of systems.
description: 9 pages, 3 figures
Επιχειρηματική αναλυτική: ανάλυση μεγάλων δεδομένων με χρήση της γλώσσας προγραμματισμού R
Creators: name: Βλάχου, Ουρανία
Publisher: name: Πανεπιστήμιο Πειραιώς
Year: 2021
Subjects: subject: Μεγάλα δεδομένα
subject: Επιχειρηματική αναλυτική
subject: Γλώσσα προγραμματισμού R

description: Στην ταχέως εξελισσόμενη πορεία της τεχνολογίας στη ζωή των ανθρώπων, κάθε οργανισμός θα πρέπει να ακολουθεί αυτή την εξελικτική πορεία προκειμένου να είναι βιώσιμος και λειτουργικός. Τα τελευταία χρόνια ο ορισμός «μεγάλα δεδομένα» κυριαρχεί στον κόσμο της αναλυτικής των επιχειρήσεων, προκειμένου να αντιμετωπιστεί η αβεβαιότητα στον επιχειρηματικό τομέα, συλλέγονται δεδομένα που μέσω διαφόρων τεχνικών επιτυγχάνεται η εξαγωγή χρήσιμων πληροφοριών. Ωστόσο ο μεγάλος όγκος των δεδομένων αυτών καθιστά τις κλασσικές τεχνικές της επιχειρησιακής έρευνας αδύνατες να εφαρμοστούν. Για αυτό το λόγο οι επιχειρήσεις κατέφυγαν στην εξέλιξη των προ αναφερόντων τεχνικών ώστε να διαχειρίζονται την πολυπλοκότητα και τον μεγάλο όγκο των δεδομένων προκειμένου να αποκτούν ανταγωνιστικό πλεονέκτημα μέσω των χρήσιμων αποτελεσμάτων από την σωστή διαχείριση τους. Έτσι δημιουργήθηκε ο όρος «Επιχειρηματική Ανάλυση» που αναλύεται στην παρούσα διπλωματική εργασία.
The impact of Foreign Direct Investment on Economic Growth, The Case of Somalia
Creators: name: Ismail Ali Sheikhnor, Dr.Turan Erol
Publisher: name: Zenodo
Year: 2024

description: The purpose of this research is to look at the influence of foreign direct investment on Somalia's economic growth. Economic growth, as defined by the Real growth of GDP, is one of the macroeconomic variables considered in the study (RGDPGR). Foreign Direct Investment (FDI), Unemployment Rate (UemplR), which is also a dependent variable for measuring changes in employment levels, and finally Import of Goods (IMPG) and Export of Goods (EXPG) for further measuring the country's surplus or deficit, and finally Gross Capital Investment (GCI), which is an independent variable that indicates fixed and project investment in the country. The study which is time series study data covering period of 32 years starting from 1989 to 2021. These study employed unit roots test mainly, the Augmented Dickey-Fuller (ADF) and Phillips Perron (PP) tests to check for stationarity. Following that was a cointegration test utilizing Johansen (1990) and Juselius's Vector Error Correction Models (VECM) approach (1995). The result of the study indicates that FDI had a strong beneficial influence on employment, implying that increased FDI inflows may increase the opportunities for local people to work, reducing unemployment and poverty in Somalia in the long run. Furthermore, it has been established that FDI has a positive significant influence on product export by boosting capital domestic investment, which in turn actually intensifies elements of production, namely labor and capital, in the long term, which is vital for production and real GDP growth.
Global existence and uniqueness for the Lake equations with vanishing topography : elliptic estimates for degenerate equations
Creators: name: Didier, Bresch
name: Metivier, Guy
Publisher: name: arXiv
Year: 2006
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 35Q30, 35B40, 76D05

description: This paper deals with global existence and uniqueness for the lake equations with a bottom topography vanishing on the shore. Our result generalizes previous studies that assumed the depth to be nondegenerate. Elliptic estimates for degenerate equations has to be established studying the behavior of the associated Green function.
Control of superexchange interactions with DC electric fields
Creators: name: Furuya, Shunsuke C.
name: Takasan, Kazuaki
name: Sato, Masahiro
Publisher: name: arXiv
Year: 2021
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We discuss DC electric-field controls of superexchange interactions. We first present generic results about antiferromagnetic and ferromagnetic superexchange interactions valid in a broad class of Mott insulators, where we also estimate typical field strength to observe DC electric-field effects: $\sim 1~\mathrm{MV/cm}$ for inorganic Mott insulators such as transition-metal oxides and $\sim 0.1~\mathrm{MV/cm}$ for organic ones. Next, we apply these results to geometrically frustrated quantum spin systems. Our theory widely applies to (quasi-)two-dimensional and thin-film systems and one-dimensional quantum spin systems on various lattices such as square, honeycomb, triangular, and kagome ones. In this paper, we give our attention to those on the square lattice and on the chain. For the square lattice, we show that DC electric fields can control a ratio of the nearest-neighbor and next-nearest-neighbor exchange interactions. In some realistic cases, DC electric fields make the two next-nearest-neighbor interactions nonequivalent and eventually turns the square-lattice quantum spin system into a deformed triangular-lattice one. For the chain, DC electric fields can induce singlet-dimer and Haldane-dimer orders. We show that the DC electric-field-induced spin gap $\propto |\boldsymbol E|^{2/3}$ in the Heisenberg antiferromagnetic chain will reach $\sim 10~\%$ of the dominant superexchange interaction in the case of a spin-chain compound $\mathrm{KCuMoO_4(OH)}$ when the DC electric field of $\sim 1~\mathrm{MV/cm}$ is applied.
An economical method to calculate eigenvalues of the Schroedinger Equation
Creators: name: Rawitscher, G. H.
name: Koltracht, I.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: The method is an extension to negative energies of a spectral integral equation method to solve the Schroedinger equation, developed previously for scattering applications. One important innovation is a re-scaling procedure in order to compensate for the exponential behaviour of the negative energy Green's function. Another is the need to find approximate energy eigenvalues, to serve as starting values for a subsequent iteration procedure. In order to illustrate the new method, the binding energy of the He-He dimer is calculated, using the He-He TTY potential. In view of the small value of the binding energy, the wave function has to be calculated out to a distance of 3000 a.u. Two hundred mesh points were sufficient to obtain an accuracy of three significant figures for the binding energy, and with 320 mesh points the accuracy increased to six significant figures. An application to a potential with two wells separated by a barrier, is also made.
description: 19 pages, 3 figures, submitted to Eur. J. Phys
"Easier to believe than to reflect": the British Columbia Social Credit movement, 1932-1952
Creators: name: Kuffert, Leonard B.
Publisher: name: University of British Columbia
Year: 2009

description: Historians and political scientists have explained the pre-eminence of Social Credit in British Columbia during the last half of this century as an institutionalized protest against the seeming inactivity of partisan governments and as a reaction to the strength of the social democratic element in the province's political culture. This thesis examines the period from 1932 up to and including the BC Social Credit movement's electoral breakthrough in 1952 and suggests that economic and political conditions during that time affected the way that Social Crediters organized and changed the focus of Social Credit ideology in BC from monetary reform to a call for good government and conservative values. It also suggests that some previous conclusions about BC's Social Credit movement - that it was an outgrowth of Alberta Social Credit, that it was a populist organization, that it was too small to be intellectually significant - should be modified in the light of new evidence. This thesis should serve as a starting point for more specialized studies of the Social Credit movement in British Columbia.
Optimization-Based Algebraic Multigrid Coarsening Using Reinforcement Learning
Creators: name: Taghibakhshi, Ali
name: MacLachlan, Scott
name: Olson, Luke
name: West, Matthew
Publisher: name: arXiv
Year: 2021
Subjects: subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Large sparse linear systems of equations are ubiquitous in science and engineering, such as those arising from discretizations of partial differential equations. Algebraic multigrid (AMG) methods are one of the most common methods of solving such linear systems, with an extensive body of underlying mathematical theory. A system of linear equations defines a graph on the set of unknowns and each level of a multigrid solver requires the selection of an appropriate coarse graph along with restriction and interpolation operators that map to and from the coarse representation. The efficiency of the multigrid solver depends critically on this selection and many selection methods have been developed over the years. Recently, it has been demonstrated that it is possible to directly learn the AMG interpolation and restriction operators, given a coarse graph selection. In this paper, we consider the complementary problem of learning to coarsen graphs for a multigrid solver, a necessary step in developing fully learnable AMG methods. We propose a method using a reinforcement learning (RL) agent based on graph neural networks (GNNs), which can learn to perform graph coarsening on small planar training graphs and then be applied to unstructured large planar graphs, assuming bounded node degree. We demonstrate that this method can produce better coarse graphs than existing algorithms, even as the graph size increases and other properties of the graph are varied. We also propose an efficient inference procedure for performing graph coarsening that results in linear time complexity in graph size.
description: Advances in Neural Information Processing Systems (NeurIPS2021)
Reconstruction of the temporal signaling network in Salmonella-infected human cells
Creators: name: Gungor Budak
name: Oyku Eren Ozsoy
name: Yesim Aydin Son
name: Can, Tolga
name: Tuncbag, Nurcan
Publisher: name: F1000Research
Year: 2015

description: Experimental hits for changes in the signaling components are usually incomplete. A complete view of biological processes can be obtained by using network modeling approaches. We reconstructed the temporal signaling network of a published temporal phosphoproteomic dataset of Salmonella-infected human cells by using the Prize-collecting Steiner Forest (PCSF) approach and the Integer Linear Programming (ILP) based edge inference approach. Results revealed critical entities and targets of Salmonella effectors which were not included in the experimental dataset.
Cooling the Commons: Pilot Research Report
Creators: name: Mellick Lopes, Abby
name: Gibson, Katherine
name: Crabtree, Louise
name: Armstrong, Helen
Publisher: name: Western Sydney University
Year: 2016

description: This pilot study provides initial insights into how residents living in Western Sydney keep cool during the hottest parts of the year and how they would like to see their living environments, at home and out and about, modified to improve wellbeing in a climate changing world. The research responds to the lack of qualitative information about: day to day living practices in outer suburban Sydney; the constraints people experience when trying to keep cool; and, people’s aspirations for more comfortable living environments. The study reviewed factors that combine to produce urban heating in Sydney’s rapidly developing urban fringe and the key socio-environmental issues that researchers have identified as important. These include the health effects of periods of extreme heat and the loss of shading and cooling effects as the tree canopy is further degraded. Our research highlighted the dearth of information about how residents move around in space and interact with the physical environment and in turn how the changing built environment on the urban fringe is shaping new forms of individual and social behaviour.
Japanese Virtual Observatory (JVO) as an advanced astronomical research enviroment
Creators: name: Shirasaki, Y.
name: Tanaka, M.
name: Kawanomoto, S.
name: Honda, S.
name: Ohishi, M.
name: Mizumoto, Y.
name: Yasuda, N.
name: Masunaga, Y.
name: Ishihara, Y.
name: Tsutsumi, J.
name: Nakamoto, H.
name: Kobayashi, Y.
name: Sakamoto, M.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present the design and implementation of the Japanese Virtual Observatory (JVO) system. JVO is a portal site to various kinds of astronomical resources distributed all over the world. We have developed five components for constructing the portal: (1) registry, (2) data service, (3) workflow system, (4) data analysis service (5) portal GUI. Registry services are used for publishing and searching data services in the VO, and they are constructed using an OAI-PMH metadata harvesting protocol and a SOAP web service protocol so that VO standard architecture is applied. Data services are developed based on the Astronomical Data Query Language (ADQL) which is an international VO standard and an extension of the standard SQL. The toolkit for building the ADQL-based service is released to the public on the JVO web site. The toolkit also provides the protocol translation from a Simple Image Access Protocol (SIAP) to ADQL protocol, so that both the VO standard service can be constructed using our toolkit. In order to federate the distributed databases and analysis services, we have designed a workflow language which is described in XML and developed execution system of the workflow. We have succeeded to connect to a hundred of data resources of the world as of April 2006. We have applied this system to the study of QSO environment by federating a QSO database, a Subaru Suprim-Cam database, and some analysis services such a SExtractor and HyperZ web services. These experiences are described is this paper.
description: 13 pages, 6 figures, submitted to SPIE Astronomical Telescopes & Instrumentation, the Advanced Software and Control for Astronomy conference in Orlando
Προμελέτη σκοπιμότητας ίδρυσης εταιρείας yachting στο Πόρτο Χέλι
Creators: name: Δημαράκης, Σαράντος
Publisher: name: Πανεπιστήμιο Πειραιώς
Year: 2021
Subjects: subject: Yachting

description: H συγκεκριμένη διπλωματική εργασία πραγματεύεται την προμελέτη σκοπιμότητας ίδρυσης εταιρείας yachting στο Πόρτο Χέλι Αργολίδας.
Black Holes and the Swampland: the Deep Throat revelations
Creators: name: Li, Yixuan
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Multi-centered bubbling solutions are black hole microstate geometries that arise as smooth solutions of 5-dimensional $\mathcal{N}=2$ Supergravity. When these solutions reach the scaling limit, their resulting geometries develop an infinitely deep throat and look arbitrarily close to a black hole geometry. We depict a connection between the scaling limit in the moduli space of Microstate Geometries and the Swampland Distance Conjecture. The naive extension of the Distance Conjecture implies that the distance in moduli space between a reference point and a point approaching the scaling limit is set by the proper length of the throat as it approaches the scaling limit. Independently, we also compute a distance in the moduli space of 3-centre solutions, from the Kähler structure of its phase space using quiver quantum mechanics. We show that the two computations of the distance in moduli space do not agree and comment on the physical implications of this mismatch.
description: 29 pages, 2 figures. V2: reference added. V3: revised version accepted for publication in JHEP. V4: Added funding information
Outflows driven by Giant Protoplanets
Creators: name: Machida, Masahiro N.
name: Inutsuka, Shu-ichiro
name: Matsumoto, Tomoaki
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We investigate outflows driven by a giant protoplanet using three-dimensional MHD nested grid simulations. We consider a local region around the protoplanet in the protoplanetary disk, and calculate three models: (a) unmagnetized disk model, (b) magnetized disk model having magnetic field azimuthally parallel to the disk, and (c) magnetic field perpendicular to the disk. Outflows with velocities, at least, 10 km/s are driven by the protoplanets in both magnetized disk models, while outflow does not appear in unmagnetized disk model. Tube-like outflows along the azimuthal direction of the protoplanetary disk appear in model with magnetic field being parallel to the disk. In this model, the magnetically dominated regions (i.e., density gap) are clearly contrasted from other regions and spiral waves appear near the protoplanet. On the other hand, in model with magnetic field being perpendicular to the disk, outflows are driven by a protoplanet with cone-like structure just as seen in the outflow driven by a protostar. Magnetic field lines are strongly twisted near the protoplanet and the outflows have well-collimated structures in this model.These outflows can be landmarks for searching exo-protoplanets in their formation stages. Our results indicate that the accretion rate onto the protoplanet tend to have a larger value than that expected from previous hydrodynamical calculations, since a fraction of the angular momentum of circum-planetary disk is removed by outflows, enhanced non-axisymmetric patterns caused by magnetic field, and magnetic braking. Possible implications for observation are also briefly discussed.
description: 11 pages, 3 figures, Submitted to ApJL, For high resolution figures see http://www2.scphys.kyoto-u.ac.jp/~machidam/jupiter/doc/resubmit_0703.pdf
Magnetic response of metallic nanoparticles: Geometric and weakly relativistic effects
Creators: name: Viloria, Mauricio Gómez
name: Weick, Guillaume
name: Weinmann, Dietmar
name: Jalabert, Rodolfo A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: While the large paramagnetic response measured in certain ensembles of metallic nanoparticles has been assigned to orbital effects of conduction electrons, the spin-orbit coupling has been pointed out as a possible origin of the anomalously large diamagnetic response observed in other cases. Such a relativistic effect, arising from the inhomogeneous electrostatic potential seen by the conduction electrons, might originate from the host ionic lattice, impurities, or the self-consistent confining potential. Here we theoretically investigate the effect of the spin-orbit coupling arising from the confining potential, quantifying its contribution to the zero-field magnetic susceptibility and gauging it against the ones generated by other weakly-relativistic corrections. Two ideal geometries are considered in detail, the sphere and the half-sphere, focusing on the expected increased role of the spin-orbit coupling upon a symmetry reduction, and the application of these results to actual metallic nanoparticles is discussed. The matrix elements of the different weakly-relativistic corrections are obtained and incorporated in a perturbative treatment of the magnetic field, leading to tractable semi-analytical and semiclassical expressions for the case of the sphere, while a numerical treatment becomes necessary for the half-sphere. The correction to the zero-field susceptibility arising from the spin-orbit coupling in a single sphere is quite small, and it is dominated by the weakly-relativistic kinetic energy correction, which in turn remains considerably smaller than the typical values of the nonrelativistic zero-field susceptibility. Moreover, the spin-orbit contribution to the average response for ensembles of nanoparticles with a large size dispersion is shown to vanish. The symmetry reduction in going from the single sphere to the half-sphere does not translate into a significant (...)
description: 35 pages, 9 figures
MPEC 2024-T99 : 2024 TW1
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2024
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2024 TW1

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Non-linear response of single-molecule magnets: field-tuned quantum-to-classical crossovers
Creators: name: Lopez-Ruiz, R.
name: Luis, F.
name: Millan, A.
name: Rillo, C.
name: Zueco, D.
name: Garcia-Palacios, J. L.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Quantum nanomagnets can show a field dependence of the relaxation time very different from their classical counterparts, due to resonant tunneling via excited states (near the anisotropy barrier top). The relaxation time then shows minima at the resonant fields H_{n}=n D at which the levels at both sides of the barrier become degenerate (D is the anisotropy constant). We showed that in Mn12, near zero field, this yields a contribution to the nonlinear susceptibility that makes it qualitatively different from the classical curves [Phys. Rev. B 72, 224433 (2005)]. Here we extend the experimental study to finite dc fields showing how the bias can trigger the system to display those quantum nonlinear responses, near the resonant fields, while recovering an classical-like behaviour for fields between them. The analysis of the experiments is done with heuristic expressions derived from simple balance equations and calculations with a Pauli-type quantum master equation.
description: 4 pages, 3 figures. Submitted to Phys. Rev. B, brief reports
A direct Jacobian total Lagrangian explicit dynamics finite element algorithm for real-time simulation of hyperelastic materials
Creators: name: Zhang, Jinao
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computational Engineering, Finance, and Science (cs.CE)
subject: FOS: Computer and information sciences

description: This paper presents a novel direct Jacobian total Lagrangian explicit dynamics (DJ-TLED) finite element algorithm for real-time nonlinear mechanics simulation. The nodal force contributions are expressed using only the Jacobian operator, instead of the deformation gradient tensor and finite deformation tensor, for fewer computational operations at run-time. Owing to this proposed Jacobian formulation, novel expressions are developed for strain invariants and constant components, which are also based on the Jacobian operator. Results show that the proposed DJ-TLED consumed between 0.70x and 0.88x CPU solution times compared to state-of-the-art TLED and achieved up to 121.72x and 94.26x speed improvements in tetrahedral and hexahedral meshes, respectively, using GPU acceleration. Compared to TLED, the most notable difference is that the notions of stress and strain are not explicitly visible in the proposed DJ-TLED but embedded implicitly in the formulation of nodal forces. Such a force formulation can be beneficial for fast deformation computation and can be particularly useful if the displacement field is of primary interest, which is demonstrated using a neurosurgical simulation of brain deformations for image-guided neurosurgery. The present work contributes towards a comprehensive DJ-TLED algorithm concerning isotropic and anisotropic hyperelastic constitutive models and GPU implementation. The source code is available at https://github.com/jinaojakezhang/DJTLED.
description: Published in International Journal for Numerical Methods in Engineering
Some reflections on current invasion science and perspectives for an exciting future
Creators: name: Heger, Tina
name: Jeschke, Jonathan M.
name: Kollmann, Johannes
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: biological invasions
subject: evidence-based management
subject: grand unified theory
subject: invasion science
subject: open science
subject: philosophy of science
subject: social-ecological systems
subject: theory development
subject: 500 Naturwissenschaften und Mathematik::570 Biowissenschaften; Biologie::570 Biowissenschaften; Biologie

description: Species spreading beyond their native ranges are important study objects in ecology and environmental sciences and research on biological invasions is thriving. Along with an increase in the number of publications, the research field is experiencing an increase in the diversity of methods applied and questions asked. This development has facilitated an upsurge in information on invasions, but it also creates conceptual and practical challenges. To provide more transparency on which kind of research is actually done in the field, the distinction between invasion science, encompassing the full spectrum of studies on biological invasions and the sub-field of invasion biology, studying patterns and mechanisms of species invasions with a focus on biological research questions, can be useful. Although covering a smaller range of topics, invasion biology today still is the driving force in invasion science and we discuss challenges stemming from its embeddedness in the social context. Invasion biology consists of the building blocks ‘theory’, ‘case studies’ and ‘application’, where theory takes the form of conceptual frameworks, major hypotheses and statistical generalisations. Referencing recent work in philosophy of science, we argue that invasion biology, like other biological or ecological disciplines, does not rely on the development of an all-encompassing theory in order to be efficient. We suggest, however, that theory development is nonetheless necessary and propose improvements. Recent advances in data visualisation, machine learning and semantic modelling are providing opportunities for enhancing knowledge management and presentation and we suggest that invasion science should use these to transform its ways of publishing, archiving and visualising research. Along with a stronger focus on studies going beyond purely biological questions, this would facilitate the efficient prevention and management of biological invasions.
Polynomial filter diagonalization of large Floquet unitary operators
Creators: name: Luitz, David J.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Periodically driven quantum many-body systems play a central role for our understanding of nonequilibrium phenomena. For studies of quantum chaos, thermalization, many-body localization and time crystals, the properties of eigenvectors and eigenvalues of the unitary evolution operator, and their scaling with physical system size $L$ are of interest. While for static systems, powerful methods for the partial diagonalization of the Hamiltonian were developed, the unitary eigenproblem remains daunting. In this paper, we introduce a Krylov space diagonalization method to obtain exact eigenpairs of the unitary Floquet operator with eigenvalue closest to a target on the unit circle. Our method is based on a complex polynomial spectral transformation given by the geometric sum, leading to rapid convergence of the Arnoldi algorithm. We demonstrate that our method is much more efficient than the shift invert method in terms of both runtime and memory requirements, pushing the accessible system sizes to the realm of 20 qubits, with Hilbert space dimensions $\geq 10^6$.
description: 4 pages, 4 figures, 1 table
Machine Learning Analysis of Gut Microbiome Profiles as Predictors for Colorectal Cancer Risk: A Systematic Review and Meta-Analysis
Creators: name: Ernest E. Onuiri, Daniel Amorue, Kelechi C. Umeaka
Publisher: name: Zenodo
Year: 2024

description: Colorectal cancer (CRC) ranks as the third most deadly cancer worldwide, with high mortality rates in both developed and developing regions, largely due to late-stage diagnosis. This systematic review and meta-analysis, conducted in line with PRISMA guidelines, evaluates studies published between 2016 and 2024 that explore the potential of machine learning algorithms to predict colorectal cancer risk based on gut microbiome profiles. The inclusion criteria focused on studies employing machine learning methods to develop predictive models for CRC. A total of 12 studies were reviewed, each utilizing various machine learning approaches to enhance the accuracy of CRC diagnosis. The findings underscore the transformative role of machine learning in improving diagnostic precision for CRC, particularly through the analysis of gut microbiome profiles. These results demonstrate that machine learning-driven analyses hold great promise in advancing early detection and risk prediction of colorectal cancer, thus offering a valuable tool for improving patient outcomes.
First-principles study of wurtzite InN$(0001)$ and $(000{\bar 1})$ surfaces
Creators: name: Gan, Chee Kwan
name: Srolovitz, David J.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Density-functional calculations are used to study various plausible structures of the wurtzite InN $(0001)$ and $(000{\bar 1})$ surfaces. These structures include the unreconstructed surfaces, surfaces with monolayers of In or N, several possible coverages and locations of In or N adatoms and vacancies. The stable structure of the $(0001)$ surface under N-rich conditions is the unreconstructed, In-terminated, surface, while under In-rich conditions the stable surface has a 3/4 monolayer of In atoms. The stable structure of the InN $(000{\bar 1})$ surface corresponds to a full monolayer of In atoms in the atop sites (directly above the N atoms) over the entire range of accessible In (or N) chemical potential. The atomic structures of the low-energy structures are also discussed.
Deuterium scattering experiments in CTEQ global QCD analyses: a comparative investigation
Creators: name: Accardi, A.
name: Hobbs, T. J.
name: Jing, X.
name: Nadolsky, P. M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Experimental measurements in deep-inelastic scattering and lepton-pair production on deuterium targets play an important role in the flavor separation of $u$ and $d$ (anti)quarks in global QCD analyses of the parton distribution functions (PDFs) of the nucleon. We investigate the impact of theoretical corrections accounting for the light-nuclear structure of the deuteron upon the fitted $u, d$-quark, gluon, and other PDFs in the CJ15 and CT18 families of next-to-leading order CTEQ global analyses. The investigation is done using the $L_2$ sensitivity statistical method, which provides a common metric to quantify the strength of experimental constraints on various PDFs and ratios of PDFs in the two distinct fitting frameworks. Using the $L_2$ sensitivity and other approaches, we examine the compatibility of deuteron data sets with other fitted experiments under varied implementations of the deuteron corrections. We find that freely-fitted deuteron corrections modify the PDF uncertainty at large momentum fractions and will be relevant for future PDFs affecting electroweak precision measurements.
description: 28 pages, 13 multi-panel figures, 4 tables; updated to published version with comparisons to NNLO corrections and scale variations
Systematic Evaluation of Fluorination as Modification for Peptide-Based Fusion Inhibitors against HIV-1 Infection
Creators: name: Huhmann, Susanne
name: Nyakatura, Elisabeth K.
name: Rohrhofer, Anette
name: Moschner, Johann
name: Schmidt, Barbara
name: Eichler, Jutta
name: Roth, Christian
name: Koksch, Beate
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: fluorinated amino acids
subject: gp41
subject: medicinal chemistry
subject: protein engineering
subject: protein-protein interactions
subject: 500 Naturwissenschaften und Mathematik::570 Biowissenschaften; Biologie::570 Biowissenschaften; Biologie

description: With the emergence of novel viruses, the development of new antivirals is more urgent than ever. A key step in human immunodeficiency virus type 1 (HIV-1) infection is six-helix bundle formation within the envelope protein subunit gp41. Selective disruption of bundle formation by peptides has been shown to be effective; however, these drugs, exemplified by T20, are prone to rapid clearance from the patient. The incorporation of non-natural amino acids is known to improve these pharmacokinetic properties. Here, we evaluate a peptide inhibitor in which a critical Ile residue is replaced by fluorinated analogues. We characterized the influence of the fluorinated analogues on the biophysical properties of the peptide. Furthermore, we show that the fluorinated peptides can block HIV-1 infection of target cells at nanomolar levels. These findings demonstrate that fluorinated amino acids are appropriate tools for the development of novel peptide therapeutics.
Some extensions of fractional Brownian motion and sub-fractional Brownian motion related to particle systems
Creators: name: Bojdecki, Tomasz
name: Gorostiza, Luis G.
name: Talarczyk, Anna
Publisher: name: arXiv
Year: 2007
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60G18, 60J80

description: In this paper we study three self-similar, long-range dependence, Gaussian processes. The first one, with covariance \int_0^{s\wedge t} u^a [(t-u)^b+(s-u)^b]du, parameters a>-1, -1
description: 11 pages; minor corrections and changes in notation
Deterministic and Stochastic Parameter Estimation for Polymer Reaction Kinetics I: Theory and Simple Examples
Creators: name: Wulkow, Niklas
name: Telgmann, Regina
name: Hungenberg, Klaus-Dieter
name: Schütte, Christof
name: Wulkow, Michael
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: deterministic and Bayesian parameter estimation
subject: experimental data
subject: polymerization kinetics
subject: uncertainty quantification
subject: 500 Naturwissenschaften und Mathematik::530 Physik::530 Physik

description: Two different approaches to parameter estimation (PE) in the context of polymerization are introduced, refined, combined, and applied. The first is classical PE where one is interested in finding parameters which minimize the distance between the output of a chemical model and experimental data. The second is Bayesian PE allowing for quantifying parameter uncertainty caused by experimental measurement error and model imperfection. Based on detailed descriptions of motivation, theoretical background, and methodological aspects for both approaches, their relation are outlined. The main aim of this article is to show how the two approaches complement each other and can be used together to generate strong information gain regarding the model and its parameters. Both approaches and their interplay in application to polymerization reaction systems are illustrated. This is the first part in a two-article series on parameter estimation for polymer reaction kinetics with a focus on theory and methodology while in the second part a more complex example will be considered.
Spatial Curvature in $f(R)$ Gravity
Creators: name: Farrugia, Christine R.
name: Sultana, Joseph
name: Mifsud, Jurgen
Publisher: name: arXiv
Year: 2021
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: In this work, we consider four $f(R)$ gravity models -- the Hu-Sawicki, Starobinsky, Exponential and Tsujikawa models -- and use a range of cosmological data, together with Markov Chain Monte Carlo sampling techniques, to constrain the associated model parameters. Our main aim is to compare the results we get when $Ω_{k,0}$ is treated as a free parameter with their counterparts in a spatially flat scenario. The bounds we obtain for $Ω_{k,0}$ in the former case are compatible with a flat geometry. It appears, however, that a higher value of the Hubble constant $H_0$ allows for more curvature. Indeed, upon including in our analysis a Gaussian likelihood constructed from the local measurement of $H_0$, we find that the results favor an open universe at a little over $1σ$. This is perhaps not statistically significant, but it underlines the important implications of the Hubble tension for the assumptions commonly made about spatial curvature. We note that the late-time deviation of the Hubble parameter from its $Λ$CDM equivalent is comparable across all four models, especially in the non-flat case. When $Ω_{k,0}=0$, the Hu-Sawicki model admits a smaller mean value for $Ω_{\text{cdm},0}h^2$, which increases the said deviation at redshifts higher than unity. We also study the effect of a change in scale by evaluating the growth rate at two different wavenumbers $k_\dagger$. Any changes are, on the whole, negligible, although a smaller $k_\dagger$ does result in a slightly larger average value for the deviation parameter $b$.
description: 21 pages, 11 figures, 8 tables
Coordinated tractions increase the size of a collectively moving pack in a cell monolayer
Creators: name: Saraswathibhatla, Aashrith
name: Henkes, Silke
name: Galles, Emmett E.
name: Sknepnek, Rastko
name: Notbohm, Jacob
Publisher: name: arXiv
Year: 2021
Subjects: subject: Biological Physics (physics.bio-ph)
subject: FOS: Physical sciences

description: Cells in an epithelial monolayer coordinate motion with their neighbors giving rise to collectively moving packs of sizes spanning multiple cell diameters. The physical mechanism controlling the pack size, however, remains unclear. A potential mechanism comes from assuming that cell-substrate traction forces persist over some time scale: with large enough persistence time, collective cell packs emerge. To test this hypothesis, we measured the velocity and net traction of each cell. The data showed that in addition to having some temporal persistence, tractions were spatially correlated, suggesting that cells coordinate with their neighbors to apply tractions in the same direction. Chemical inhibitors and activators of actomyosin contraction were used to determine effects of altering the traction persistence and alignment. Numerical simulations based on the self-propelled Voronoi model, augmented to include both traction persistence and alignment and calibrated against the experimental data, matched the experimentally measured pack size. The model identified that if there were no alignment of traction between neighboring cells, the size of the collective pack would be substantially smaller than observed in the experiments. Hence, combining experiments and a simple mechanical model, this study confirms the long-standing assumption of traction persistence and adds the notion of traction alignment between neighbors. Together, persistence and alignment are two factors controlling the size of a collectively moving cell pack.
Holger Baitinger (editor), Materielle Kultur und Identität im Spannungsfeld zwischen mediterraner Welt und Mitteleuropa
Creators: name: Fernández-Götz, Manuel
Publisher: name: Bonner Jahrbücher
Year: 2021

description: Rezension zu: Holger Baitinger (editor), Materielle Kultur und Identität im Spannungsfeld zwischen mediterraner Welt und Mitteleuropa. Material Culture and Identity between the Mediterranean World and Central Europe. RGZM-Tagungen, volume 27. Publisher of the Römisch-Germanisches Zentralmuseum, Mayence 2016. 292 pages, 214 figures, 3 tables
description: Bonner Jahrbücher, Bd. 217.2017(2018): Bonner Jahrbücher