cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Soft hydraulics: from Newtonian to complex fluid flows through compliant conduits
Creators: name: Christov, Ivan C.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: Microfluidic devices manufactured from soft polymeric materials have emerged as a paradigm for cheap, disposable and easy-to-prototype fluidic platforms for integrating chemical and biological assays and analyses. The interplay between the flow forces and the inherently compliant conduits of such microfluidic devices requires careful consideration. While mechanical compliance was initially a side-effect of the manufacturing process and materials used, compliance has now become a paradigm, enabling new approaches to microrheological measurements, new modalities of micromixing, and improved sieving of micro- and nano-particles, to name a few applications. This topical review provides an introduction to the physics of these systems. Specifically, the goal of this review is to summarize the recent progress towards a mechanistic understanding of the interaction between non-Newtonian (complex) fluid flows and their deformable confining boundaries. In this context, key experimental results and relevant applications are also explored, hand-in-hand with the fundamental principles for their physics-based modeling. The key topics covered include shear-dependent viscosity of non-Newtonian fluids, hydrodynamic pressure gradients during flow, the elastic response (deformation and bulging) of soft conduits due to flow within, the effect of cross-sectional conduit geometry on the resulting fluid--structure interaction, and key dimensionless groups describing the coupled physics. Open problems and future directions in this nascent field of soft hydraulics, at the intersection of non-Newtonian fluid mechanics, soft matter physics, and microfluidics, are noted.
description: 32 pages, 14 figures, 267 references; invited topical review to appear in J. Phys.: Condens. Matter; v2: minor updates/correct typos
MPEC 2024-T96 : 2024 TT1
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 TT1

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.
Quantum computing hardware in the cloud: Should a computational chemist care?
Creators: name: Rossi, A.
name: Baity, P. G.
name: Schäfer, V. M.
name: Weides, M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Within the last decade much progress has been made in the experimental realisation of quantum computing hardware based on a variety of physical systems. Rapid progress has been fuelled by the conviction that sufficiently powerful quantum machines will herald enormous computational advantages in many fields, including chemical research. A quantum computer capable of simulating the electronic structures of complex molecules would be a game changer for the design of new drugs and materials. Given the potential implications of this technology, there is a need within the chemistry community to keep abreast with the latest developments as well as becoming involved in experimentation with quantum prototypes. To facilitate this, here we review the types of quantum computing hardware that have been made available to the public through cloud services. We focus on three architectures, namely superconductors, trapped ions and semiconductors. For each one we summarise the basic physical operations, requirements and performance. We discuss to what extent each system has been used for molecular chemistry problems and highlight the most pressing hardware issues to be solved for a chemistry-relevant quantum advantage to eventually emerge.
description: Invited Tutorial Review
Mixed-parity octupolar pairing and corner Majorana modes in three dimensions
Creators: name: Roy, Bitan
name: Juricic, Vladimir
Publisher: name: arXiv
Year: 2021
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We identify time-reversal symmetry breaking mixed-parity superconducting states that feature eight Majorana corner modes in properly cleaved three-dimensional cubic crystals. Namely, when an odd-parity isotropic $p$-wave pairing coexists with cubic symmetry preserving even-parity octupolar $d_{x^2-y^2}+i d_{3z^2-r^2}$ pairing, the gapless surface Majorana modes of the former get localized at the eight corners, thus yielding an \emph{intrinsic} third-order topological superconductor (TOTSC). A cousin $d_{xy}+id_{3z^2-r^2}$ pairing also accommodating eight corner Majorana modes, by virtue of breaking the cubic symmetry, in contrast, yields an \emph{extrinsic} TOTSC. We identify a doped octupolar (topological or trivial) Dirac insulator as a suitable platform to sustain such unconventional superconductors, realized from an intraunit cell pairing. Finally, we argue that the proposed TOTSC can be experimentally realizable in NaCl and other structurally similar compounds under high pressure.
description: Published Version: 6 Pages, 3 Figures (Supplementary Materials: as ancillary file)
Capabilities of Deep Learning Models on Learning Physical Relationships: Case of Rainfall-Runoff Modeling with LSTM
Creators: name: Yokoo, Kazuki
name: Ishida, Kei
name: Ercan, Ali
name: Tu, Tongbi
name: Nagasato, Takeyoshi
name: Kiyama, Masato
name: Amagasaki, Motoki
Publisher: name: arXiv
Year: 2021
Subjects: subject: Atmospheric and Oceanic Physics (physics.ao-ph)
subject: Machine Learning (cs.LG)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: This study investigates the relationships which deep learning methods can identify between the input and output data. As a case study, rainfall-runoff modeling in a snow-dominated watershed by means of a long- and short-term memory (LSTM) network is selected. Daily precipitation and mean air temperature were used as model input to estimate daily flow discharge. After model training and verification, two experimental simulations were conducted with hypothetical inputs instead of observed meteorological data to clarify the response of the trained model to the inputs. The first numerical experiment showed that even without input precipitation, the trained model generated flow discharge, particularly winter low flow and high flow during the snow-melting period. The effects of warmer and colder conditions on the flow discharge were also replicated by the trained model without precipitation. Additionally, the model reflected only 17-39% of the total precipitation mass during the snow accumulation period in the total annual flow discharge, revealing a strong lack of water mass conservation. The results of this study indicated that a deep learning method may not properly learn the explicit physical relationships between input and target variables, although they are still capable of maintaining strong goodness-of-fit results.
description: 8 pages, 5 figures
The Unitary Transformation in Quantum Teleportation
Creators: name: Wang, Zheng-Chuan
Publisher: name: arXiv
Year: 2006
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: In the well known treatment of quantum teleportation, the receiver should convert the state of his EPR particle into the replica of the unknown quantum state by one of four possible unitary transformations. However, the importance of these unitary transformations must be emphasized. We will show in this paper that the receiver can not transform the state of his particle into an exact replica of the unknown state which the sender want to transfer if he have not a proper implementation of these unitary transformations. In the procedure of converting state, the inevitable coupling between EPR particle and environment which is needed by the implementation of unitary transformations will reduce the accuracy of the replica.
description: 4 pages, 0 figure
Permutation-invariant quantum coding for quantum deletion channels
Creators: name: Ouyang, Yingkai
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: Information Theory (cs.IT)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: Quantum deletions, which are harder to correct than erasure errors, occur in many realistic settings. It is therefore pertinent to develop quantum coding schemes for quantum deletion channels. To date, not much is known about which explicit quantum error correction codes can combat quantum deletions. We note that {\em any} permutation-invariant quantum code that has a distance of $t+1$ can correct $t$ quantum deletions for any positive integer $t$ in both the qubit and the qudit setting. Leveraging on coding properties of permutation-invariant quantum codes under erasure errors, we derive corresponding coding bounds for permutation-invariant quantum codes under quantum deletions. We focus our attention on a specific family of $N$-qubit permutation-invariant quantum codes, which we call shifted gnu codes, and show that their encoding and decoding algorithms can be performed in $O(N)$ and $O(N^2)$.
description: 5 pages, 2 figures
A Cosmology Calculator for the World Wide Web
Creators: name: Wright, Edward L.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: A cosmology calculator that computes times and distances as a function of redshift for user-defined cosmological parameters is available on the World Wide Web. This note gives the formulae used by the cosmology calculator and discusses some of its implementation. A version of the calculator that allows one to specify the equation of state parameter w and w' and neutrino masses, and a version for converting the light travel times usually given in the popular press into redshifts are also available.
description: 8 pages with 1 included figure. Cosmology calculator available at http://www.astro.ucla.edu/~wright/CosmoCalc.html, light travel time converter at http://www.astro.ucla.edu/~wright/DlttCalc.html and the advanced cosmology calculator at http://www.astro.ucla.edu/~wright/ACC.html Revised to fix a typo, add a reference, and match the accepted version to be published in the PASP
Influence of pure-dephasing by phonons on exciton-photon interfaces: Quantum microscopic theory
Creators: name: Kojima, Kunihiro
name: Tomita, Akihisa
Publisher: name: arXiv
Year: 2007
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We have developed a full quantum microscopic theory to analyze the time evolution of transversal and longitudinal components of an exciton-single photon system coupled to bulk acoustic phonons. These components are subjected to two decay processes. One is radiative relaxation and the other is pure-dephasing due to exciton-phonon interaction. The former results in a decay with an exponent linear to time, while the latter causes a faster initial decay than the radiative decay. We analyzed the dependence of the components on the duration of the input one-photon pulse, temperature, and radiative relaxation rates. Such a quantitative analysis is important for the developments of atom-photon interfaces which enable coherent transfer of quantum information between photons and atomic systems. We found that, for a GaAs spherical quantum dot in which the exciton interacts with bulk phonons, the maximal probability of the excited state can be increased up to 75 %. This probability can be considered as the efficiency for quantum information transfer from photon to exciton.
description: 9pages, 5figures
The radio luminosity, black hole mass and Eddington ratio for quasars from the Sloan Digital Sky Survey
Creators: name: Bian, Wei-Hao.
name: Chen, Yan-Mei.
name: Hu, Chen.
name: Huang, Kai.
name: Xu, Yan.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We investigate the $\mbh- σ_*$ relation for radio-loud quasars with redshift $z<0.83$ in Data Release 3 of the Sloan Digital Sky Survey (SDSS). The sample consists of 3772 quasars with better model of H$β$ and \oiii lines and available radio luminosity, including 306 radio-loud quasars, 3466 radio-quiet quasars with measured radio luminosity or upper-limit of radio luminosity (181 radio-quiet quasars with measured radio luminosity). The virial supermassive black hole mass (\mbh) is calculated from the broad \hb line, the host stellar velocity dispersion ($σ_*$) is traced by the core \oiii gaseous velocity dispersion, and the radio luminosity and the radio loudness are derived from the FIRST catalog. Our results are follows: (1) For radio-quiet quasars, we confirm that there is no obvious deviation from the $\mbh- σ_*$ relation defined in inactive galaxies when \mbh uncertainties and luminosity bias are concerned. (2) We find that radio-loud quasars deviate much from the $\mbh- σ_*$ relation respect to that for radio-quiet quasars. This deviation is only partly due to the possible cosmology evolution of the $\mbh- σ_*$ relation and the luminosity bias. (3) The radio luminosity is proportional to $\mbh^{1.28^{+0.23}_{-0.16}}(\lb/\ledd)^{1.29^{+0.31}_{-0.24}}$ for radio-quiet quasars and $\mbh^{3.10^{+0.60}_{-0.70}}(\lb/\ledd)^{4.18^{+1.40}_{-1.10}}$ for radio-loud quasars. The weaker correlation of the radio luminosity dependence upon the mass and the Eddington ratio for radio-loud quasars shows that other physical effects would account for their radio luminosities, such as the black hole spin.
description: 15 pages, 8 figures, 2 tables, accepted for publication in ChJAA
Effects of the size of cosmological N-body simulations on physical quantities II-. Halo formation and destruction rate
Creators: name: Prasad, Jayanti
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: In this study we show how errors due to finite box size affect formation and destruction rate for haloes in cosmological N-body simulations. In an earlier study we gave an analytic prescription of finding the corrections in the mass function. Following the same approach, in this paper we give analytical expressions for corrections in the formation rate, destruction rate and the rate of change in comoving number density, and compute their expected values for the power law ($n=-2$) and LCDM models.
description: 16 pages, 5 figures, Some corrections are made and new references added
Treatment outcomes of saphenous vein ligation plus foam sclerotherapy under local anaesthesia
Creators: name: Σκεπαστιανός, Γεώργιος Πέτρου
Publisher: name: Aristotle University of Thessaloniki
Year: 2018
Subjects: απολινωση σαφηνουs φλεβas
σκληροθεραπεία αφρού
ανεπάρκεια φλεβών
saphenous vein ligation
Foam sclerotherapy
Vein insufficiency

description: Σκοπός της παρούσας μελέτης είναι να επισημάνει και να μελετήσει τα ενδοεγχειρητικά, βραχυπρόθεσμα και μεσοπρόθεσμα αποτελέσματα με την εφαρμογή της συνδυασμένης τεχνικής (πρόσδεση σαφηνών φλεβών και σκληροθεραπεία αφρού) για τη θεραπεία της ανεπάρκειας σαφηνών φλεβών. Σκοπός αυτής της μελέτης είναι η αξιολόγηση του ποσοστού απόφραξης των σαφηνών φλεβών, της διεισδυτικότητας, της ειδικής μετεγχειρητικής μετεγχειρητικής υγείας και της ασφάλειας σε ασθενείς με ανεπάρκεια σαφηνών φλεβών μετά από θεραπεία με χρήση σκληροθεραπείας αφρού κατευθυνόμενης από καθετήρα σε συνδυασμό με απολίνωση της σαφηνούς φλέβας, και των ασφαλειών στη σαφηνο-μηριαία διακλάδωση υπό τοπική αναισθησία. 15 ασθενείς με συμπτωματική μονόπλευρη ανεπάρκεια σαφηνών φλεβών υποβλήθηκαν σε σκληροθεραπεία αφροδισιακής σκλήρυνσης με καθετήρα σε συνδυασμό με τοπική αναισθησία και παρακολουθήθηκαν 6 εβδομάδες μετά τη διαδικασία και στη συνέχεια ακολούθησαν σε 6 μήνες. Αποτελέσματα: εκτός από μία περίπτωση που εμφάνισαν κατά την πρώτη παρακολούθηση με κλινικά συμπτώματα της ΥΔΤ, όλοι οι άλλοι ασθενείς που παρουσίαζαν μείωση στις καταγγελίες χρόνιας ανεπάρκειας φλεβών και συμπτώματα κιρσώδους φλέβας αναφέρθηκαν στο 100% των περιπτώσεων. Η εξαφάνιση των κιρσών φλεβών επιτεύχθηκε επίσης σε όλους τους ασθενείς
description: This study aims to highlight and study intra-operative, short and midterm re- sults with the application of the combined technique (saphenous vein ligation and foam sclerotherapy) for the treatment of saphenous vein insufficiency. Purpose of this study is to evaluate the saphenous vein occlusion rate, the invasiveness, the specific health related post - operative and the safety in patients with saphenous vein insufficiency after treatment with the use of catheter directed foam sclerotherapy combined with ligation of the saphenous vein, and collaterals in the sapheno-femoral junction under local anaesthesia. 15 patients with symptomatic unilateral saphenous vein insufficiency under- went catheter directed foam sclerotherapy combined wit saphenous vein liga- tion under local anaesthesia, and were followed up 6 weeks after the proce- dure and then further follow at 6 months. Results : except from one case who presented at the first follow up with clini- cal symptoms of DVT all other patients presented with decrease of complaints of chronic vein insufficiency and varicose vein symptoms was reported in 100% of the cases. Disappearance of varicose veins was also achieved in all patients
Aspects of gravitational decoherence in neutrino lensing
Creators: name: Swami, Himanshu
name: Lochan, Kinjalk
name: Patel, Ketan M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study decoherence effects in neutrino flavour oscillations in curved spacetime with particular emphasis on the lensing in a Schwarzschild geometry. Assuming Gaussian wave packets for neutrinos, we argue that the decoherence length derived from the exponential suppression of the flavour transition amplitude depends on the proper time of the geodesic connecting the events of the production and detection in general gravitational setting. In the weak gravity limit, the proper time between two events of given proper distance is smaller than that in the flat spacetime. Therefore, in presence of a Schwarzschild object, the neutrino wave packets have to travel relatively more physical distance in space to lapse the same amount of proper time before they decoher. For non-radial propagation applicable to the lensing phenomena, we show that the decoherence, in general, is sensitive to the absolute values of neutrino masses as well as the classical trajectories taken by neutrinos between the source and detector along with the spatial widths of neutrino wave packets. At distances beyond the decoherence length, the probability of neutrino flavour transition due to lensing attains a value which depends only on the leptonic mixing parameters. Hence, the observability of neutrino lensing significantly depends on these parameters and in-turn the lensing can provide useful information about them.
description: 13 pages, 2 figures, Published version
MPEC 2024-T97 : 2024 TU1
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 TU1

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.
Joint Dereverberation and Separation with Iterative Source Steering
Creators: name: Nakashima, Taishi
name: Scheibler, Robin
name: Togami, Masahito
name: Ono, Nobutaka
Publisher: name: arXiv
Year: 2021
Subjects: subject: Audio and Speech Processing (eess.AS)
subject: Sound (cs.SD)
subject: Signal Processing (eess.SP)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: We propose a new algorithm for joint dereverberation and blind source separation (DR-BSS). Our work builds upon the IRLMA-T framework that applies a unified filter combining dereverberation and separation. One drawback of this framework is that it requires several matrix inversions, an operation inherently costly and with potential stability issues. We leverage the recently introduced iterative source steering (ISS) updates to propose two algorithms mitigating this issue. Albeit derived from first principles, the first algorithm turns out to be a natural combination of weighted prediction error (WPE) dereverberation and ISS-based BSS, applied alternatingly. In this case, we manage to reduce the number of matrix inversion to only one per iteration and source. The second algorithm updates the ILRMA-T matrix using only sequential ISS updates requiring no matrix inversion at all. Its implementation is straightforward and memory efficient. Numerical experiments demonstrate that both methods achieve the same final performance as ILRMA-T in terms of several relevant objective metrics. In the important case of two sources, the number of iterations required is also similar.
description: 5 pages, 2 figures, accepted at ICASSP 2021
Tight contact structures and genus one fibered knots
Creators: name: Baldwin, John A.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Symplectic Geometry (math.SG)
subject: Geometric Topology (math.GT)
subject: FOS: Mathematics

description: We study contact structures compatible with genus one open book decompositions with one boundary component. Any monodromy for such an open book can be written as a product of Dehn twists around dual non-separating curves in the once-punctured torus. Given such a product, we supply an algorithm to determine whether the corresponding contact structure is tight or overtwisted. We rely on Ozsv{á}th-Szab{ó} Heegaard Floer homology in our construction and, in particular, we completely identify the $L$-spaces with genus one, one boundary component, pseudo-Anosov open book decompositions. Lastly, we reveal a new infinite family of hyperbolic three-manifolds with no co-orientable taut foliations, extending the family discovered in \cite{RSS}.
description: 30 pages, 10 figures. Added figures, extended result to all monodromies, and added sections 5 and 6
Spitzer 24 micron Survey of Debris Disks in the Pleiades
Creators: name: Gorlova, Nadya
name: Rieke, George H.
name: Muzerolle, James
name: Stauffer, John R.
name: Siegler, Nick
name: Young, Erick T.
name: Stansberry, John H.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We performed a 24 micron 2 Deg X 1 Deg survey of the Pleiades cluster, using the MIPS instrument on Spitzer. Fifty four members ranging in spectral type from B8 to K6 show 24 micron fluxes consistent with bare photospheres. All Be stars show excesses attributed to free-free emission in their gaseous envelopes. Five early-type stars and four solar-type stars show excesses indicative of debris disks. We find a debris disk fraction of 25 % for B-A members and 10 % for F-K3 ones. These fractions appear intermediate between those for younger clusters and for the older field stars. They indicate a decay with age of the frequency of the dust-production events inside the planetary zone, with similar time scales for solar-mass stars as have been found previously for A-stars.
description: accepted to ApJ
Redirected Walking in Static and Dynamic Scenes Using Visibility Polygons
Creators: name: Williams, Niall L.
name: Bera, Aniket
name: Manocha, Dinesh
Publisher: name: arXiv
Year: 2021
Subjects: subject: Robotics (cs.RO)
subject: Graphics (cs.GR)
subject: FOS: Computer and information sciences

description: We present a new approach for redirected walking in static and dynamic scenes that uses techniques from robot motion planning to compute the redirection gains that steer the user on collision-free paths in the physical space. Our first contribution is a mathematical framework for redirected walking using concepts from motion planning and configuration spaces. This framework highlights various geometric and perceptual constraints that tend to make collision-free redirected walking difficult. We use our framework to propose an efficient solution to the redirection problem that uses the notion of visibility polygons to compute the free spaces in the physical environment and the virtual environment. The visibility polygon provides a concise representation of the entire space that is visible, and therefore walkable, to the user from their position within an environment. Using this representation of walkable space, we apply redirected walking to steer the user to regions of the visibility polygon in the physical environment that closely match the region that the user occupies in the visibility polygon in the virtual environment. We show that our algorithm is able to steer the user along paths that result in significantly fewer resets than existing state-of-the-art algorithms in both static and dynamic scenes. Our project website is available at https://gamma.umd.edu/vis_poly/.
Επικοινωνία και Διαχείριση Κρίσεων: Μελέτη Περίπτωσης των εταιρικών κρίσεων της Nestle και ΙΚΕΑ
Creators: name: Παπαναστασίου, Μαρία Ζωή Ιωάννη
Publisher: name: Aristotle University of Thessaloniki
Year: 2018
Subjects: Επικοινωνία-Διαχείριση Κρίσεων
Μέσα Κοινωνικής Δικτύωσης
Communication
Crisis Management
Social Media

description: Οι κρίσεις ανακύπτουν είτε από ενδογενείς είτε από εξωγενείς παράγοντες. Η μελέτη της επικοινωνίας και της διαχείρισης κρίσεων είναι ένα μείζον ζήτημα που θα απασχολεί πάντα τις εταιρίες. Η ουσία στη μελέτη της επικοινωνιακής διαχείρισης κρίσεων είναι οι στρατηγικές που υιοθετούνται από τις εταιρίες για την επίλυση μιας κρίσης. Κάθε εταιρία και κάθε κρίση είναι διαφορετική, το ίδιο και η πολιτική της επικοινωνιακής διαχείρισης. Σημαντικό ρόλο στη διαχείριση μιας κρίσης διαδραματίζουν τα Μέσα Κοινωνικής Δικτύωσης (Social Media), τα οποία συμβαδίζουν με τη σημερινή ψηφιακή εποχή και λειτουργούν ως μέσο επικοινωνίας των εταιριών με το κοινό. Συγκεκριμένα, η εργασία περιλαμβάνει το θεωρητικό πλαίσιο στο οποίο αναλύονται οι έννοιες των κρίσεων και της εταιρικής επικοινωνίας, καθώς επίσης και το πώς τα «Social Media» λειτουργούν ως εργαλείο στην επικοινωνιακή διαχείριση κρίσεων. Στη συνέχεια, ακολουθεί το κομμάτι της μεθοδολογίας της έρευνας, όπου χρησιμοποιήθηκε η ποιοτική μέθοδος. Ειδικότερα, επιλέχθηκε η ποιοτική μέθοδος «μελέτη περίπτωσης», η οποία εστίασε σε δύο περιπτώσεις κρίσεων των εταιριών Nestlé και ΙΚΕΑ
description: Crises emerge from either endogenous or exogenous factors. Studying the Communication and Management of Crises is a major issue for every corporation, and the strategy to be followed in order to overcome a crisis is an essential part of the whole process. Each and every corporation, as well as the policies concerning a crisis management is different. The role of Social Media in overcoming such a crisis is nowadays a determining element, with Social Media being a bridge of communication between the companies and the users. The following paper includes the theory and analysis of the concepts of a “Crisis” and “Corporate communication”, as well as the use of social media as a tool of communication in crisis management. Then, followed by the text the part of Research Methodology, where the quantitive method has been used . More specifically, the case studies of Nestle and IKEA co. are presented, with the interviews with the communication managers of both corporations being used as the main research tool. The third and fourth part of this paper consist of the case studies of Nestle and IKEA in a time of crisis
Polarization in Strong-Field Ionization of Excited Helium
Creators: name: Bray, A. C.
name: Maxwell, A. S.
name: Kissin, Y.
name: Ruberti, M.
name: Ciappina, M. F.
name: Averbukh, V.
name: Faria, C. Figueira De Morisson
Publisher: name: arXiv
Year: 2021
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: We analyze how bound-state excitation, electron exchange and the residual binding potential influence above-threshold ionization (ATI) in Helium prepared in an excited $p$ state, oriented parallel and perpendicular to a linearly polarized mid-IR field. Using ab initio B-spline Algebraic Diagrammatic Construction (ADC), and several one-electron methods with effective potentials, including the Schrödinger solver Qprop, modified versions of the Strong-Field Approximation and the Coulomb-Quantum Orbit Strong-Field Approximation (CQSFA), we find that these specific physical mechanisms leave significant imprints in ATI spectra and photoelectron momentum distributions. Examples are changes of up to two orders of magnitude in the high-energy photoelectron region, and ramp-like structures that can be traced back to Coulomb-distorted trajectories. The present work also shows that electron exchange renders rescattering less effective, causing suppressions in the ATI plateau. Due to the long-range potential, the electron continuum dynamics are no longer confined to the polarization axis, in contrast to the predictions of traditional approaches. Thus, one may in principle probe excited-state configurations perpendicular to the driving-field polarization without the need for orthogonally polarized fields.
description: 26 pages, 8 figures. Fig. 5 has been compressed in order to meet the arXiV requirements. In the revised version, we have streamlined parts of the theory, modified some discussions and the conclusions, and added references
Identifying Priorities for Enhancing Gender in Science in Africa; Outcome Document for the Virtual Experts’ Consultative Roundtable Held on 23 July 2020
Creators: name: Accelerating Excellence In Science In Africa (AESA)
Publisher: name: AAS Open Research
Year: 2021

description: This outcome document captures the proceedings of the expert consultation roundtable held on the 23rd July and a literature synthesis exercise on the status of enhancing gender in science in Africa, and identification of challenges and opportunities for investment within this strategic priority area. This document precedes the policy paper that will reflect the consensus of different stakeholders on key priorities to achieve the greatest return on investment in enhancing gender equity in science.
Finite size effects in the spin-1 XXZ and supersymmetric sine-Gordon models with Dirichlet boundary conditions
Creators: name: Ahn, Changrim
name: Nepomechie, Rafael I.
name: Suzuki, Junji
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Starting from the Bethe Ansatz solution of the open integrable spin-1 XXZ quantum spin chain with diagonal boundary terms, we derive a set of nonlinear integral equations (NLIEs), which we propose to describe the boundary supersymmetric sine-Gordon model BSSG${}^{+}$ with Dirichlet boundary conditions on a finite interval. We compute the corresponding boundary $S$ matrix, and find that it coincides with the one proposed by Bajnok, Palla and Takács for the Dirichlet BSSG${}^{+}$ model. We derive a relation between the (UV) parameters in the boundary conditions and the (IR) parameters in the boundary $S$ matrix. By computing the boundary vacuum energy, we determine a previously unknown parameter in the scattering theory. We solve the NLIEs numerically for intermediate values of the interval length, and find agreement with our analytical result for the effective central charge in the UV limit and with boundary conformal perturbation theory.
description: correcting the title of the paper
A Framework for the Implementation of Genomic Medicine for Public Health in Africa
Creators: name: Accelerating Excellence In Science In Africa (AESA)
Publisher: name: AAS Open Research
Year: 2021

description: The aim of this framework document is to highlight these elements within the African context and provide some recommendations on how African countries can work on putting them in place by building on existing infrastructure. This will enable resource limited countries to start implementing appropriate genomics-based health-related interventions, drawing on experiences from elsewhere, but adapting to the African context where necessary. The document is written by volunteers, who are not necessarily experts in genomic or precision medicine but have a variety of data, science and clinical backgrounds. It is not aiming to be prescriptive or comprehensive, but rather to provide some information and recommendations to enable the implementation of genomic medicine. The document focuses on the clinical context, while indicating barriers to implementation (situational and needs), which includes additional research that is required for knowledge and evidence generation.
Optimal quantum circuits for general phase estimation
Creators: name: van Dam, W.
name: D'Ariano, G. M.
name: Ekert, A.
name: Macchiavello, C.
name: Mosca, M.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We address the problem of estimating the phase phi given N copies of the phase rotation gate u(phi). We consider, for the first time, the optimization of the general case where the circuit consists of an arbitrary input state, followed by any arrangement of the N phase rotations interspersed with arbitrary quantum operations, and ending with a POVM. Using the polynomial method, we show that, in all cases where the measure of quality of the estimate phi' for phi depends only on the difference phi'-phi, the optimal scheme has a very simple fixed form. This implies that an optimal general phase estimation procedure can be found by just optimizing the amplitudes of the initial state.
description: 4 pages, 3 figures
Study of isospin violating $ϕ$ excitation in $e^+e^- \to ωπ^0$
Creators: name: Li, Gang
name: Zhang, Yuan-Jiang
name: Zhao, Qiang
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We study the reaction $e^+ e^-\to ωπ^0$ in the vicinity of $ϕ$ mass region. The isospin-violating $ϕ$ excitation is accounted for by two major mechanisms. One is electromagnetic (EM) transition and the other is strong isospin violations. For the latter, we consider contributions from the intermediate hadronic meson loops and $ϕ$-$ρ^0$ mixing as the major mechanisms via the $t$ and s-channel transitions, respectively. By fitting the recent KLOE data, we succeed in constraining the model parameters and extracting the $ϕ\toωπ^0$ branching ratio. It shows that the branching ratio is sensitive to the $ϕ$ excitation line shape and background contributions. Some crucial insights into the correlation between isospin violation and Okubo-Zweig-Iizuka (OZI) rule evading transitions are also learned.
description: Revised version to appear in J. Phys. G
Terrestrial Consequences of Spectral and Temporal Variability in Ionizing Photon Events
Creators: name: Ejzak, Larissa M.
name: Melott, Adrian L.
name: Medvedev, Mikhail V.
name: Thomas, Brian C.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: Atmospheric and Oceanic Physics (physics.ao-ph)
subject: Biological Physics (physics.bio-ph)
subject: Geophysics (physics.geo-ph)
subject: Populations and Evolution (q-bio.PE)
subject: FOS: Physical sciences
subject: FOS: Biological sciences

description: Gamma-Ray Bursts (GRBs) directed at Earth from within a few kpc may have damaged the biosphere, primarily though changes in atmospheric chemistry which admit greatly increased Solar UV. However, GRBs are highly variable in spectrum and duration. Recent observations indicate that short (~0.1 s) burst GRBs, which have harder spectra, may be sufficiently abundant at low redshift that they may offer an additional significant effect. A much longer timescale is associated with shock breakout luminosity observed in the soft X-ray (~10^3 s) and UV (~10^5 s) emission, and radioactive decay gamma-ray line radiation emitted during the light curve phase of supernovae (~10^7 s). Here we generalize our atmospheric computations to include a broad range of peak photon energies and investigate the effect of burst duration while holding total fluence and other parameters constant. The results can be used to estimate the probable impact of various kinds of ionizing events (such as short GRBs, X-ray flashes, supernovae) upon the terrestrial atmosphere. We find that the ultimate intensity of atmospheric effects varies only slightly with burst duration from 10^-1 s to 10^8 s. Therefore, the effect of many astrophysical events causing atmospheric ionization can be approximated without including time development. Detailed modeling requires specification of the season and latitude of the event. Harder photon spectra produce greater atmospheric effects for spectra with peaks up to about 20 MeV, because of greater penetration into the stratosphere.
description: 30 pages, to be published in ApJ. Replaced for conformity with published version, including correction of minor typos and updated references
Τί θεός: Η περί θεού διδασκαλία στον Πλάτωνα και τους Στωικούς
Creators: name: Γαλανάκης, Δημήτριος Χρήστου
Publisher: name: Aristotle University of Thessaloniki
Year: 2018
Subjects: Θεολογία του Πλάτωνα
Ορφισμός
Πρώιμος Στωικισμός
Plato’s theology
Orphism
Early Stoicism

description: Σκοπός της διατριβής ήταν η μελέτη του θεολογικού συστήματος του Πλάτωνα και των πρώιμων στωικών φιλοσόφων. Εξετάστηκαν τα στοιχεία της θεολογίας όπως αυτά παρουσιάζονται από τον Πλάτωνα στους διαλόγους του και ακολουθήθηκε με την ταξινόμηση του F. Solmsen. Στην συνέχεια αφιερώθηκε ένα κεφάλαιο για την συζήτηση σχετικά με την επίδραση του Πλάτωνα από την Ορφική διδασκαλία. Δεν μπορούν δυστυχώς να εξαχθούν βέβαια συμπεράσματα λόγω της έλλειψης επαρκών πηγών, της αποσπασματικής φύσης των Ορφικών αποσπασμάτων, αλλά και της σύγχυσης που επικρατεί μεταξύ της Ορφικής και Πυθαγορικής παράδοσης. Τέλος, εξετάσαμε την πρώιμη στωική θεολογία στην οποία ο θεός έχει σωματική φύση και αποτελεί την ενεργή αρχή του κόσμου. Μέσα από την ύλη, που είναι η παθητική αρχή παράγει ό,τι υπάρχει. Αφιερώσαμε, επίσης, κάποιες σελίδες για την μελέτη του Ύμνο στον Δία του Κλεάνθη όπου εκτυλίσσεται το θεολογικό σύστημα του φιλοσόφου. Το κείμενο είναι σπουδαίο καθώς είναι το μοναδικό ακέραιο σωζόμενο έργο των πρώιμων Στωικών.
description: The aim of this paper was the study of Plato’s and the early Stoic’s theology. We examined the theological elements in the platonic dialogues and we followed F. Solmsen’s categorization. In addition, we dedicated a chapter for the discussion about the Orphic influence on Plato. Unfortunately, we cannot conclude certainly due to the fragmental nature of the Orphic scripts and the confusion between Orphism and Pythagoreanism. Finally, we examined the early stoic theology, which contains a corporeal god -the active principle of the world. Through matter, that is the passive principle, produces everything in existence. We also analyzed Cleanthes’ Hymn to Zeus, where the philosopher expresses though a poetic form his theological thought. It is one of the most important texts we have, because it the only complete and surviving evidence of the early Stoics.
Infinitely many 4d $\mathcal{N}=2$ SCFTs with $a=c$ and beyond
Creators: name: Kang, Monica Jinwoo
name: Lawrie, Craig
name: Song, Jaewon
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study a set of four-dimensional $\mathcal{N}=2$ superconformal field theories (SCFTs) $\widehatΓ(G)$ labeled by a pair of simply-laced Lie groups $Γ$ and $G$. They are constructed out of gauging a number of $\mathcal{D}_p(G)$ and $(G, G)$ conformal matter SCFTs; therefore they do not have Lagrangian descriptions in general. For $Γ= D_4, E_6, E_7, E_8$ and some special choices of $G$, the resulting theories have identical central charges $(a=c)$ without taking any large $N$ limit. Moreover, we find that the Schur indices for such theories can be written in terms of that of $\mathcal{N}=4$ super Yang--Mills theory upon rescaling fugacities. Especially, we find that the Schur index of $\widehat{D}_4(SU(N))$ theory for $N$ odd is written in terms of MacMahon's generalized sum-of-divisor function, which is quasi-modular. For generic choices of $Γ$ and $G$, it can be regarded as a generalization of the affine quiver gauge theory obtained from $D3$-branes probing an ALE singularity of type $Γ$. We also comment on a tantalizing connection regarding the theories labeled by $Γ$ in the Deligne--Cvitanović exceptional series.
description: 33pages+appendix, 8 tables, 4 figures
Δέσμευση και αποδέσμευση από την ισχύ των ασφαλιστικών μέτρων
Creators: name: Μιχαλάκης, Αιμίλιος – Σπύρος Κίμωνα
Publisher: name: Aristotle University of Thessaloniki
Year: 2018
Subjects: Προσωρινό δεδικασμένο
Ασφαλιστικά μέτρα
Ισχύς ασφαλιστικών μέτρων
Temporary res judicata
Provisional measures
Force of provisional measures

description: Στόχος της εργασίας είναι να εξεταστεί το είδος της παραγόμενης από την απόφαση ασφαλιστικών μέτρων δέσμευσης, οι τρόποι κατάλυσης της ισχύος της και να αναδειχθούν τα προβλήματα από την μετενέργειά της. Το στοιχείο που καθορίζει την εμβέλεια του «προσωρινού» δεδικασμένου που απορρέει από την απόφαση ασφαλιστικών μέτρων είναι η έννοια της «διάγνωσης». Ερευνάται λοιπόν αν η απόφαση ασφαλιστικών μέτρων φέρει διαγνωστικά στοιχεία. Από τη συγκριτική λοιπόν επισκόπηση της έννοιας και της λειτουργίας τόσο του κατά κυριολεξία δεδικασμένου (άρθρο 321 επ. ΚΠολΔ) όσο και του «προσωρινού δεδικασμένου» διαπιστώνεται η συστοιχία (αντίστοιχη λειτουργία) του τελευταίου προς το πρώτο. Γι’ αυτό τον λόγο, το δεδικασμένο που απορρέει από την απόφαση ασφαλιστικών μέτρων οριοθετείται με όμοιο τρόπο σε σχέση με το δεδικασμένο απόφασης της οριστικής δίκης. Αποδέσμευση από την ισχύ των ασφαλιστικών μέτρων επιχειρείται με την υποβολή νέας αίτησης ασφαλιστικών μέτρων, με την υποβολή ανακλητικών αιτήσεων και με την αποδυνάμωση της απόφασης για πολλούς λόγους. Τέλος εξετάζεται το ζήτημα της μετενέργειας της απόφασης, δηλαδή το πώς μπορεί να επηρεαστεί η διαπλασθείσα από την απόφαση κατάσταση, σε περίπτωση που καταλυθεί η ισχύς του ασφαλιστικού μέτρου.
description: The aim of this thesis is to examine the type of the binding act from the judgement of provisional remedies, the ways of release and the problems from the after-action of this judgment. The determining factor which defines the range of the “temporary” res judicata is the meaning of “diagnosis”. In this thesis, the subject of examination is whether the judgment of provisional remedies has diagnostic features. Therefore, from the comparative survey of the concept and the function of both the force of final judgment in a strict sense (art. 321 CCP) and the "provisional force of final judgement", the correlation (corresponding function) of the latter to the former is established. For this reason, this res judicata has the same limits with the res judicata of the final judgement. The release from the force of provisional remedies is accomplished by lodging a new application or revocatory - reformative petitions or by the weakening of the judgment by other causes. Finally, the problem of the after-action of the judgment, is also examined. Which is how the situation created by the judgement can be affected if the binding of the judgment has been abolished.
Probing Hawking radiation through capacity of entanglement
Creators: name: Kawabata, Kohki
name: Nishioka, Tatsuma
name: Okuyama, Yoshitaka
name: Watanabe, Kento
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We consider the capacity of entanglement in models related with the gravitational phase transitions. The capacity is labeled by the replica parameter which plays a similar role to the inverse temperature in thermodynamics. In the end of the world brane model of a radiating black hole the capacity has a peak around the Page time indicating the phase transition between replica wormhole geometries of different types of topology. Similarly, in a moving mirror model describing Hawking radiation the capacity typically shows a discontinuity when the dominant saddle switches between two phases, which can be seen as a formation of island regions. In either case we find the capacity can be an invaluable diagnostic for a black hole evaporation process.
description: 28 pages, 12 figures; v2: typos corrected, references added; v3: typos corrected, references added, published version
Dark matter substructure and gamma-ray annihilation in the Milky Way halo
Creators: name: Diemand, Juerg
name: Kuhlen, Michael
name: Madau, Piero
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present initial results from ``Via Lactea'', the highest resolution simulation to date of Galactic CDM substructure. It follows the formation of a Milky Way-size halo with Mvir=1.8x10^12 Msun in a WMAP 3-year cosmology, using 234 million particles. Over 10,000 subhalos can be identified at z=0: Their cumulative mass function is well-fit by N(>Msub)= 0.0064 (Msub/Mvir)^(-1) down to Msun=4x10^6 Msun. The total mass fraction in subhalos is 5.3%, while the fraction of surface mass density in substructure within a projected distance of 10 kpc from the halo center is 0.3%. Because of the significant contribution from the smallest resolved subhalos, these fractions have not converged yet. Sub-substructure is apparent in all the larger satellites, and a few dark matter lumps are resolved even in the solar vicinity. The number of dark satellites with peak circular velocities above 10 km/s (5 km/s) is 124 (812): of these, 5 (26) are found within 0.1 Rvir, a region that appeared practically smooth in previous simulations. The neutralino self-annihilation gamma-ray emission from dark matter clumps is approximately constant per subhalo mass decade. Therefore, while in our run the contribution of substructure to the gamma-ray luminosity of the Galactic halo amounts to only 40% of the total spherically-averaged smooth signal, we expect this fraction to grow significantly as resolution is increased further. An all-sky map of the expected annihilation gamma-ray flux reaching a fiducial observer at 8 kpc from the Galactic center shows that at the current resolution a small number of subhalos start to be bright enough to be visible against the background from the smooth density field surrounding the observer.
description: 15 pages, 10 figures. ApJ accepted. Movies, images and a version with higher resolution figures are available at http://www.ucolick.org/~diemand/vl/