cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The first measurement of the quasar lifetime distribution
Creators: name: Khrykin, Ilya S.
name: Hennawi, Joseph F.
name: Worseck, Gabor
name: Davies, Frederick B.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Understanding the growth of the supermassive black holes powering luminous quasars, their co-evolution with host galaxies, and impact on the surrounding intergalactic medium depends sensitively on the duration of quasar accretion episodes. Unfortunately, this time-scale, known as the quasar lifetime, $t_{\rm Q}$, is still uncertain by orders of magnitude ($t_{\rm Q}\simeq 0.01~{\rm Myr}-1~{\rm Gyr}$). However, the extent of the He II Ly$α$ proximity zones in the absorption spectra of $z_{\rm qso}\sim3-4$ quasars constitutes a unique probe, providing sensitivity to lifetimes up to $\sim 30$ Myr. Our recent analysis of $22$ archival He II proximity zone spectra reveals a surprisingly broad range of emission timescales, indicating that some quasars turned on $\lesssim 1$ Myr ago, whereas others have been shining for $\gtrsim 30$ Myr. Determining the underlying quasar lifetime distribution (QLD) from proximity zone measurements is a challenging task owing to: 1) the limited sensitivity of individual measurements; 2) random sampling of the quasar light curves; 3) density fluctuations in the quasar environment; and 4) the inhomogeneous ionization state of He II in a reionizing IGM. We combine a semi-numerical He II reionization model, hydrodynamical simulations post-processed with ionizing radiative transfer, and a novel statistical framework to infer the QLD from an ensemble of proximity zone measurements. Assuming a log-normal QLD, we infer a mean $\langle {\rm log}_{10}\left(t_{\rm Q}/{\rm Myr}\right)\rangle=0.22^{+0.22}_{-0.25}$ and standard deviation $σ_{{\rm log}_{10}t_{\rm Q}}=0.80^{+0.37}_{-0.27}$. Our results allow us to estimate the probability of detecting young quasars with $t_{\rm Q}\leq0.1$ Myr from their proximity zone sizes yielding $p\left(\leq 0.1~{\rm Myr}\right)=0.19^{+0.11}_{-0.09}$, which is broadly consistent with recent determination at $z\sim 6$.
description: 14 pages, 10 figures, submitted to MNRAS
Longitudinal flow and onset of deconfinement
Creators: name: Petersen, H.
name: Bleicher, M.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: The effects of the onset of deconfinement on longitudinal and transverse flow are studied. First, we analyze longitudinal pion spectra from $E_{\rm lab}= 2A$ GeV to $\sqrt{s_{\rm NN}}=200$ GeV within Landau's hydrodynamical model and the UrQMD transport approach. From the measured data on the widths of the pion rapidity spectra, we extract the sound velocity $c_s^2$ in the early stage of the reactions. It is found that the sound velocity has a local minimum (indicating a softest point in the equation of state, EoS) at $E_{\rm beam}=30A$ GeV. This softening of the EoS is compatible with the assumption of the formation of a mixed phase at the onset of deconfinement. Furthermore, the energy excitation function of elliptic flow ($v_2$) from $E_{\rm beam}=90A$ MeV to $\sqrt{s_{\rm NN}}=200$ GeV is explored within the UrQMD framework and discussed in the context of the available data. The transverse flow should also be sensitive to changes in the equation of state. Therefore, the underestimation of elliptic flow by the UrQMD model calculation above $E_{\rm lab}= 30A$ GeV might also be explained by assuming a phase transition from a hadron gas to the quark gluon plasma around this energy. This would be consistent with the model calculations, indicating a transition from hadronic matter to ``string matter'' in this energy range.
description: Proceedings of the 3rd International Workshop The Critical Point and Onset of Deconfinement, Firenze, Italy
Zeeman term for the Néel vector in a two sublattice antiferromagnet using Dzyaloshinsky-Moriya interaction and magnetic field
Creators: name: Dasgupta, Sayak
name: Zou, Ji
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We theoretically investigate the dynamics of solitons in two sublattice antiferromagnets under external perturbations, focusing on the effect of Dzyaloshinsky-Moriya (DM) interactions. To this end, we construct a micromagnetic field theory for the antiferromagnet in the presence of the external magnetic field, DM interaction, and spin-transfer torque. In particular, we show external magnetic field and spin current couple to Néel vector in a Zeeman-like manner when DM interactions present, which can be used to efficiently drive antiferromagnetic solitons of different dimensions. Besides, we study the effect of straining the local lattice. It can serve as an external handle on the Néel field inertia and thus dynamical properties. Our findings may find applications in antiferromagnetic spintronics.
description: 11 pages, 6 figures, additonal calculations of Magnus type dynamics
Rapidity dependence of the photon to pion production ratio in high energy collisions
Creators: name: Jalilian-Marian, Jamal
Publisher: name: arXiv
Year: 2007
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We investigate rapidity dependence of the ratio of photon and pion production cross sections in high energy proton (deuteron) - nucleus collisions at RHIC and LHC. This ratio, and its rapidity dependence can be a sensitive probe of high density QCD (Color Glass Condensate) dynamics and shed further light on the role of saturation physics at RHIC and LHC.
description: 8 pages, 3 figures
Αντιστροφή δεδομένων δυναμικών πεδίων: εφαρμογές στον ελληνικό χώρο
Creators: name: Reci, Hamza H.
Publisher: name: Aristotle University of Thessaloniki
Year: 2003
Subjects: Μετασχηματισμός
Μιγαδικά χαρακτηριστικά
Τοπικές εκτιμήσεις
Transformation
Complex attributes
Local estimates

description: Στην διδακτορική διατριβή αυτή ο σκοπός ήταν η αντιστροφή δεδομένων πενιών δυναμικού(βαρυτικού και ψευδομαγνητικού πεδίου) στον Ελληνικό χώρο. Χρησιμοποιήθηκαν τα βαρυτικά δεδομένα του Ελληνικού χώρου τα οποία συλλέχτηκαν από διάφορους ελληνικούς φορείς. Δίνονται έννοιες για τα πεδία δυναμικού, τους μετασχηματισμούς και ο ρόλος που παίζει ο καθένας στην κατανόηση των ανωμαλιών. Περιγράφονται οι πιθανές ανομοιογένειας πυκνότητας και μαγνητικής επιδεκτικότητας που εντοπίστηκαν στην δομή του εσωτερικού της γης με βάση τις εκτιμήσεις(βάθος, παράταξη, κλίση, αζιμούθιο επαφών), που προέκυψαν από την μέθοδο των μιγαδικών χαρακτηριστικών. Επίσης γίνεται προσπάθεια συσχέτισης των πηγών με τις ελληνίδες γεωτεκτονικές ζώνες. Δείχνεται το τρισδιάστατο μοντέλο της επιδεκτικότητας που προέκυψε από την φιλτραρισμένη ανωμαλία(ψευδομαγνητική) μετά την φιλτραρισμένη ανωμαλία(ψευδομαγνητική) μετά την αποκοπή των μηκών κύματος των μικροτέρων των 100km
description: The target of this dissertation is the inversion of potential fields(gravity and pseudomagnetics) in Greek area. The gravity data of Greek area collected by different greek institutions were used. Concepts of potential fields are illustrated with examples, also are used transformations of potential fields and is shown the role of each in understanding the anomalies. With the complex attributes analysis are described the possible unhomogenities of density and magnetic susceptibility that came up from filtered pseudomagnetic anomaly after ented off the wave lenghts less than 100km is shown for the greek area until a depth 150km.
Should I stay or should I go? Nursing and midwifery academics intention to stay in or leave academia: A scoping review
Creators: name: Tower, M
name: Muir, R
name: Zimmerman, PA
name: Carter, AG
name: Maude, Robyn
name: Hollaway, K
name: Geia, L
name: Massey, D
name: Elder, E
Publisher: name: Open Access Te Herenga Waka-Victoria University of Wellington
Year: 2024
Subjects: classificationCode: 42
subject: Health sciences
subject: FOS: Health sciences
classificationCode: 3901
subject: Curriculum and pedagogy
classificationCode: 4204
subject: Midwifery
classificationCode: 4205
subject: Nursing

description: Background: There is a chronic lack of appropriately qualified nurses and midwives being attracted into and remaining in the academic workforce. Reasons for this are not well understood but have been linked to stressful work environments related to balancing multiple roles in sometimes unsupportive environments, resulting in overload and demoralisation. Aim: To illuminate factors associated with nursing and midwifery academics' intention to remain in academia and factors associated with intention to leave. Design: A scoping review was undertaken to provide a comprehensive and broad analysis of the related literature. This was guided by Arksey and O'Malley. A search strategy was developed using a combination of keywords and subject headings and adapted for four electronic databases to search for papers published between 2013 and 2024. Methods: The review included five steps: (i) identifying the question, (ii) identifying relevant studies, (iii) study selection, (iv) data charting, (v) collating, summarising, and reporting the results. Covidence systematic review software was used. Quality appraisal was undertaken using the Mixed Methods Assessment Tool (MMAT). Results: A total of 2870 papers were identified, 23 were included in the review. Retaining academics includes addressing issues related to promotion positive work environments such teamwork, professional relationships, supporting older academics, and professional development. Preventing attrition includes addressing emotional exhaustion and burnout, and ensuring academics feel valued and are recognised. Notably, there was a lack of research related to the Indigenous nursing and midwifery academic workforce. Conclusion: Given the predicted workforce shortages it is imperative for nursing education providers to develop strategies to promote healthy work environments and career pathways, and identify how to develop strong leadership in an ageing nursing and midwifery academic workforce. Importantly, the lack of research related to the Indigenous academic workforce is concerning and must be a priority area for focus.
The influence of the earth’s rotation on the wind-driven flow in Hecate Strait, British Columbia
Creators: name: Hannah, Charles Gordon
Publisher: name: University of British Columbia
Year: 2008

description: A regional model of the depth-averaged currents in Hecate Strait, British Columbia has been developed: the Hecate Strait Model. When driven by local winds the model simulates the winter transport fluctuations and captures the character of the observed circulation patterns. The modelled currents are consistent with the historical view of the winter circulation and contain the counter-current observed in southern Hecate Strait. The counter-current is due to topographic steering: the tendency, in a rotating fluid, for the flow to follow the local depth contours. The model results suggest a new interpretation of the observed currents in southern Hecate Strait, which has implications for particle transport. The influence of the earth’s rotation on the water transport through Hecate Strait is investigated using the concept of rotation-limited-flux. The effect of rotation is to reduce the flux through the strait compared with a non-rotating strait. Numerical experiments with the Hecate Strait Model show that the earth’s rotation reduces the steady state transport by a factor of three. The relationship between the steady-state transport and the Coriolis parameter is consistent with rotation-limited-flux.
Ο πίνακας Hilbert σε χώρους αναλυτικών συναρτήσεων
Creators: name: Διαμαντόπουλος, Επαμεινώνδας
Publisher: name: Aristotle University of Thessaloniki
Year: 2003
Subjects: Πίνακας Hilbert
Πίνακες Hankel
Τελεστές σύνθεσης
Χώροι Bergman
Χώροι Dirichlet
Hilbert matrix
Hankel matrix
Composition operator
Bergman spaces
Dirichlet spaces

description: Μελετούμε τον τελεστή τύπου Hankel που παράγεται από τη δράση του πίνακα Hilbert σε συντελεστές αναλυτικών συναρτήσεων. Η διατριβή αποτελείται από τέσσερα κεφάλαια. Το πρώτο είναι κεφάλαιο αναφοράς όπου παρουσιάζουμε τις προαπαιτούμενες γνώσεις για να γίνει κατανοητή η εργασία. Στο δεύτερο κεφάλαιο δείχνουμε ότι ο τελεστής αυτός ορίζεται καλώς στους χώρους Hardy και βρίσκουμε εκτιμήσεις για τη νόρμα του. Στο τρίτο κεφάλαιο χρησιμοποιώντας παρόμοια διαδικασία, βρίσκουμε εκτιμήσεις για τη νόρμα αυτού του τελεστή στους χώρους Bergman του μοναδιαίουδίσκου. Τέλος στο τέταρτο κεφάλαιο θεωρούμε μια γενικότερη οικογένεια τελεστών τύπου Hankel, αποδεικνύουμε ότι αυτοί είναι φραγμένοι σε χώρους Dirichlet και βρίσκουμε συνθήκες ώστε αυτοί οι τελεστές να είναι συμπαγείς ή να ανήκουν στις κλάσεις Shatten οι οποίες είναι υποσύνολα της κλάσης των συμπαγών τελεστών.
description: We study the operator, induced by the action of Hilbert matrix on coefficients of analytic functions. This thesis consists of four chapters. First chapter is a referee chapter where we present the tools we need to develop the rest of the work. In the second chapter, we show that the operator is well defined on Hardy spaces of the unit disc and we find estimations for its norm. In the third chapter using a similar procedure we find estimations for the norm of the operator on Bergman spaces of the unit disc. Finally in chapter four we consider a family of Hankel type operators. We prove that under a specific condition, that operators are bounded on Dirichlet spaces. In addition, we find conditions so that the operators we study, belong in compact class or Schutten classes which are subclasses of the class of compact operators.
ATLASGAL -- selected massive clumps in the inner Galaxy. IX. Deuteration of ammonia
Creators: name: Wienen, M.
name: Wyrowski, F.
name: Walmsley, C. M.
name: Csengeri, T.
name: Pillai, T.
name: Giannetti, A.
name: Menten, K. M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Deuteration has been used as a tracer of the evolutionary phases of low- and high-mass star formation. The APEX Telescope Large Area Survey (ATLASGAL) provides an important repository for a detailed statistical study of massive star-forming clumps in the inner Galactic disc at different evolutionary phases. We study the amount of deuteration using NH2D in a representative sample of high-mass clumps discovered by the ATLASGAL survey covering various evolutionary phases of massive star formation. Unbiased spectral line surveys at 3 mm were thus conducted towards ATLASGAL clumps between 85 and 93 GHz with the Mopra telescope and from 84 to 115 GHz using the IRAM 30m telescope. A subsample was followed up in the NH2D transition at 74 GHz with the IRAM 30m telescope. We determined the deuterium fractionation from the column density ratio of NH2D and NH3 and measured the NH2D excitation temperature for the first time from the simultaneous modelling of the 74 and 110 GHz line using MCWeeds. We find a large range of the NH2D to NH3 column density ratio up to 1.6+/-0.7 indicating a high degree of NH3 deuteration in a subsample of the clumps. Our analysis yields a clear difference between NH3 and NH2D rotational temperatures for a fraction of the sources. We therefore advocate observation of the NH2D transitions at 74 and 110 GHz simultaneously to determine the NH2D temperature directly. We determine a median ortho-to-para column density ratio of 3.7+/-1.2. The high detection rate of NH2D confirms a high deuteration previously found in massive star-forming clumps. Using the excitation temperature of NH2D instead of NH3 is needed to avoid an overestimation of deuteration. We measure a higher detection rate of NH2D in sources at early evolutionary stages. The deuterium fractionation shows no correlation with evolutionary tracers such as the NH3 (1,1) line width, or rotational temperature.
U_e(1)xU_g(1) Actions in 2+1-Dimensions: Full Vectorial Electric and Magnetic Fields
Creators: name: Ferreira, P. Castelo
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: It is considered a dimensional reduction of Ue(1)xUg(1) 3+1-dimensional electromagnetism with a gauge field (photon) and a pseudo-vector gauge field (pseudo-photon) to 2+1-dimensions. In the absence of boundary effects, the quantum structure is maintained, while when boundary effects are considered, as have been previously studied, a cross Chern-Simons term between both gauge fields is present, which accounts for topological effects and changes the quantum structure of the theory. Our construction maintains the dimensional reduced action invariant under parity (P) and time-inversion (T). We show that the theory has two massive degrees of freedom, corresponding to the longitudinal modes of the photon and of the pseudo-photon and briefly discuss the quantization procedures of the theory in the topological limit (wave functional quantization) and perturbative limit (an effective dynamical current theory), pointing out directions to solve the constraints and deal with the negative energy contributions from pseudo-photons. We recall that the physical interpretation of the fields in the planar system is new and is only meaningful in the context of Ue(1)xUg(1) electromagnetism. In this work it is shown that all the six electromagnetic vectorial fields components are present in the dimensional reduced theory and that, independently of the embedding of the planar system, can be described in terms of the two gauge fields only. As far as the author is aware it is the first time that such a construction is fully justified, thus allowing a full vectorial treatment at variational level of electromagnetism in planar systems.
description: 8 pages, 1 figure
Homogeneous model for the TRAPPIST-1e planet with an icy layer
Creators: name: Gevorgyan, Yeva
Publisher: name: arXiv
Year: 2021
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: In this work we investigate whether a multilayered planet can be approximated as a homogeneous planet, and in particular how well the dissipation rate of a multilayered planet can be reproduced with a homogeneous rheology. We study the case of a stratified body with an icy crust that, according to recent studies, displays a double peak feature in the tidal response that cannot be reproduced with a homogeneous planet with an Andrade rheology. We revisit the problem with a slightly more complex rheology for the homogeneous body, the Sundberg-Cooper rheology, which naturally has a double peak feature, and apply the model to the TRAPPIST-1e planet. Our results compare very well with the results obtained when employing a multilayered model, showing that it is possible to approximate the behavior of a multilayer icy planet with a homogeneous planet using the Sundberg-Cooper rheology. This highlights the fact that we do not need the complexity of the multilayer planet model in order to estimate the tidal dissipation of an icy planet.
description: Accepted in A&A. Short note, 13 pages, 5 figures, 15 references
Quantum information
Creators: name: Horodecki, Ryszard
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: This article reviews the extraordinary features of quantum information predicted by the quantum formalism, which, combined with the development of modern quantum technologies, have opened new horizons in quantum physics that can potentially affect various areas of our live, leading to new technologies such as quantum cybersecurity, quantum communication, quantum metrology, and quantum computation.
description: This review article is based on a lecture on quantum information given at the XLVI Extraordinary Congress of Polish Physicists, Warsaw, Poland, October 16-18, 2020, on the occasion of the centenary of the Polish Physical Society. 37 pages, 4 figures. Minor textual changes, reference added
Applying weighted network measures to microarray distance matrices
Creators: name: Ahnert, S. E.
name: Garlaschelli, D.
name: Fink, T. M. A.
name: Caldarelli, G.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: Biological Physics (physics.bio-ph)
subject: Quantitative Methods (q-bio.QM)
subject: FOS: Physical sciences
subject: FOS: Biological sciences

description: In recent work we presented a new approach to the analysis of weighted networks, by providing a straightforward generalization of any network measure defined on unweighted networks. This approach is based on the translation of a weighted network into an ensemble of edges, and is particularly suited to the analysis of fully connected weighted networks. Here we apply our method to several such networks including distance matrices, and show that the clustering coefficient, constructed by using the ensemble approach, provides meaningful insights into the systems studied. In the particular case of two data sets from microarray experiments the clustering coefficient identifies a number of biologically significant genes, outperforming existing identification approaches.
description: Accepted for publication in J. Phys. A
Schottky Barrier Heights of Defect-free Metal/ZnO, CdO, MgO and SrO Interfaces
Creators: name: Chen, Jiaqi
name: Zhang, Zhaofu
name: Guo, Yuzheng
name: Robertson, John
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The Schottky barrier heights (SBHs) of defect-free interfaces of ZnO, CdO, MgO and SrO with various metals and different terminations are investigated by density functional supercell calculations. The oxide bands are corrected for their density functional band gap error by applying U-type treatment to their metal-d and O-p states where necessary. The p-type SBHs are found to decrease linearly with increasing metal work function. The pinning factor S of the non-polar and polar interfaces are similar for each oxide. S is found to be 0.26, 0.56, 0.74 and 0.96 for CdO, ZnO, MgO and SrO, respectively, with S increasing for increased oxide ionicity. The calculated pinning factors are generally consistent with the metal-induced gap states (MIGS) model in terms of variation with ionicity and dielectric constant. A significant shift of SBHs from the non-polar to the polar interfaces of 0.4 eV, 1 eV and 0.5 eV for ZnO, MgO and SrO, respectively, can be explained by an interfacial dipole. Our results are also useful to describe Co,Fe|MgO interfaces in magnetic tunnel junctions.
description: 13 pages, 6 figures
Τροποποίηση επιφανειακής δομής υλικών με διεργασίες πλάσματος
Creators: name: Ορφανουδάκη, Θεοδώρα
Publisher: name: Aristotle University of Thessaloniki
Year: 2004
Subjects: Ινες ενεργού άνθρακα
Ανθρακούχα μοριακά κόσκινα
Activated carbon fibers
Carbon molecular sieves

description: Στόχοι της παρούσας διατριβής ήταν : α) η διερεύνηση της δυνατότητας παραγωγής ενεργών ανθράκων με διεργασίες πλάσματος αέρα β) η τροποποίηση ινών ενεργού άνθρακα με διεργασίες πολυμερισμού πλάσματος στην κατεύθυνση της εκλεκτικλης ρόφησης CO2 έναντι CH4. Για τα χαρακτηρισμό της πορώδους δομής των ανθρακούχων υλικών χρησιμοποιήθηκαν η προσφόρηση Ν2 στους 77Κ καθώς και η προσφόρηση CO2 στους 298Κ. Ο χαρακτηρισμός της χημικής δομής των υλικών πραγματοποιήθηκε με φασματοσκοπικές τεχνικές όπως : Raman, FTIR και XPS. Οι ιδιότητες κοσκίνου των υλικών αξιολογήθηκαν με μέτρηση των κινητικών καμπυλών ρόφησης CO2 & CH4 σε θερμοκρασία περιβάλλοντος και υπολογισμό της ιδανικής εκλεκτικότητας CO2/CH4. Για την οπτική παρατήρηση των υλικών χρησιμοποιήθηκε μικροσκοπία ηλεκτρονικής σάρωσης. Το σύνολο των αποτελεσμάτων οδηγεί στο συμπέρασμα ότι το πλάσμα αέρα δεν μπορεί να αποτελέσει μέθοδο ενεργοποίησης ανθρακούχων υλικών. Αντίθετα η εναπόθεση υμενίου στην επιφάνεια των ινών με διεργασίες πολυμερισμού πλάσματος οδηγεί στη δημιουργία σύνθετων υλικών με πολύ σημαντικές ικανότητες διαχωρισμού CO2 & CH4.
description: The scopes of he current study were : a) the potential production of activated carbons by selective air, b) the activated carbon fiber modification for the selective adsorption of CO2 against CH4. The materials pore structure characterisation was performed using N2 adsorption at 77k and O2 adsorption at 298K. The chemical structure of the carbonaceous materials was evaluated using spectroscopic techniques such as Raman, FITR and XPS. Gas separation properties of the produced materials were estimated by CO2 and CH4 uptale curves measurement at room tempature and CO2/CH4 ideal selectivity calculation. SEM measurement were performed for the study of the modified materials. Results obtained revealed that plasma air processes are not suitable for activated carbon fiber surface resulted in the formation of composite material possessing significant CO2/CH4 gas separation properties
Spitzer IRS Spectroscopy of Intermediate Polars: Constraints on Mid-Infrared Cyclotron Emission
Creators: name: Harrison, Thomas E.
name: Campbell, Ryan K.
name: Howell, Steve B.
name: Cordova, France A.
name: Schwope, Axel D.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present Spitzer Infrared Spectrograph (IRS) observations of eleven intermediate polars (IPs). Spectra covering the wavelength range from 5.2 to 14 $μ$m are presented for all eleven objects, and longer wavelength spectra are presented for three objects (AE Aqr, EX Hya, and V1223 Sgr). We also present new, moderate resolution (R $\sim$ 2000) near-infrared spectra for five of the program objects. We find that, in general, the mid-infrared spectra are consistent with simple power laws that extend from the optical into the mid-infrared. There is no evidence for discrete cyclotron emission features in the near- or mid-infrared spectra for any of the IPs investigated. If cyclotron emission is occurring in the 5.2 to 14.0 $μ$m bandpass it constitutes less than 1% of the bolometric luminosity of any of the IPs. We discuss our results in the context of the standard model for IPs.
description: 43 pages, including 17 figures, accepted by the Astrophysical Journal
PRÉ-NATAL ODONTOLÓGICO: CONHECIMENTO DE ALUNOS INGRESSANTES E CONCLUINTES DE ODONTOLOGIA
Creators: name: Ramos, Bruna Luiza Maximo
name: Soares, Josiane P.
name: Ziemer, José Guilherme
Publisher: name: Zenodo
Year: 2024

description: A realização do pre-natal com acompanhamento médico consolidou-se como uma realidade e rotina na vida da mulher gestante incluindo, também, acompanhamento odontológico. O objetivo

deste estudo foi avaliar nível de conhecimento entre os acadêmicos ingressantes e concluintes de um curso de graduacão em Odontologia do estado de Santa Catarina, no sul do Brasil, sobre o pré-natal odontológico. Foi aplicado um questionário previamente estruturado sobre os conhecimentos do pré-natal odontológico e para caracterizacão dos acadêmicos. Os dados foram analisados pelo software estatístico JAMOVI (IOS) versão 2.3.2, para associacão das variáveis independentes pelo teste do qui- quadrado (p<0.05). Para avaliacão dos dados descritivos foi utilizado o software Microsoft Excel.

Como resultados, 79,3% dos participantes informaram ter conhecimento sobre o pré-natal odontológico, porém, quando abordados sobre terapêutica medicamentosa e procedimentos aplicados as gestantes, a maioria dos estudantes concluintes apontou que exames radiográficos, anestésicos locais, analgésicos e antibióticos são seguros para as gestantes, enquanto que entre os alunos ingressantes a maioria apontou não serem seguros em sua aplicabilidade (p<.001). Conclui-se que, os alunos concluintes do curso de graduacão em Odontologia possuem um conhecimento significativamente maior em relacão aos alunos ingressantes acerca do pré-natal odontológico.
Equidistant frequency triplets in pulsating stars: The Combination Mode Hypothesis
Creators: name: Breger, M.
name: Kolenberg, K.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Multiplet structures are a common feature in pulsating stars, and can be the consequence of rotational splitting, mode interaction or sinusoidal amplitude variations. In this paper we examine the phenomenon of (nearly) equidistant triplets, which are unlikely to be caused by rotational splitting, in different types of pulsating stars: a Delta Scuti variable (1 Mon), an RR Lyrae variable (RR Lyr) and a short-period Cepheid (V743 Lyr). We examine the hypothesis that one of the modes forming the triplet results from a combination of the other two modes. The analyses were carried out on recent data sets by using multiple-frequency analyses and statistics with the package PERIOD04. In particular, the small departures from equidistance were calculated for the three selected stars. For the Delta Scuti variable 1 Mon, the departure from equidistance is only 0.000079 +- 0.000001 c/d (or 0.91 +- 0.01 nHz). For 1 Mon the Combination Mode Hypothesis with a mode excited by resonance is the most probable explanation. For the star RR Lyr, the hypothesis of resonance through a combination of modes should be considered. The results for the best-studied cepheid with a Blazhko period (V743 Lyr) are inconclusive because of an unfavorable period of 1.49d and insufficient data.
description: 6 pages, 1 figure, accepted for publication in Astronomy and Astrophysics
Some remarks on the division of cognitive labor
Creators: name: Viola, Marco
Publisher: name: Università degli Studi di Milano
Year: 2015
Subjects: social epistemology; economic epistemology; divison of cognitive labor

description: Since the publication of Kitcher’s influential paper The Division of Cognitive Labor, some philosophers wondered about these two related issues: (1) which is the optimal distribution of cognitive efforts among rival methods within a scientific community?, and (2) whether and how can a community achieve such an optimal distribution? Though not committing to any specific answer to question (1), I claim that issue (2) does not depend exclusively on an invisible hand like mechanism, since both intra-scientific and extra-scientific institutions may play a major role. Finally, I examine some practical difficulties of reallocating scientists from a method to another, which leads to stress the importance of well-planned training and recruitment.
description: RT. A Journal on Research Policy and Evaluation, Vol 3, No 1 (2015)
Μονάδες δασικής βλάστησης του όρους Πάϊκου και αξιολόγησή τους από αναδασωτική σκοπιά
Creators: name: Κοράκης, Γεώργιος Χ.
Publisher: name: Aristotle University of Thessaloniki
Year: 2003

description: Στην παρούσα έρευνα, μελετήθηκε φυτοκοινωνιολογικά, με την μέθοδο του Braun-Blanquet(1951,1964), η δασική βλάστηση του όρους Πάικου. Διενεργήθηκαν συνολικά 259 φυτοληψίες. Με τη μέθοδο της επεξεργασίας των φυτοληψιών σε φυτοπίνακες με το χέρι, διακρίθηκαν φυτοκοινωνικές μονάδες διάφορης ιεραρχικής ταξινόμησης. Για την διερεύνηση των εδαφικών συνθηκών του σταθμού και τον προσδιορισμό της σχέσης τους με τη βλάστηση, διενεργήθηκαν 19 εδαφοτομές. Μετά την τελική επεξεργασία και την συνταξινόμηση, οι φυτοκοινωνικές μονάδες που προέκυψαν είναι τρεις κλάσεις, τρεις τάξεις, πέντε συνενώσεις, τέσσερεις ενώσεις, εννέα κοινότητες, τέσσερεις υποενώσεις, έντεκα υποκοινότητες, δεκατρείς παραλλαγές και δεκαεννέα όψεις
description: In the present study the forest vegetation of Paiko massif(northcentral Greece) was investigated phytosociologicaly, using the Braun-Blanquet(1951, 1964) method. A total amount of 259 reveles were table method and phytosociological units of several syntaxinomic rank were discerned. For the investigation of the soil conditions of the site and the determination of soil relation with vegetation, 19 soil profiles were elaborated. The phytosociological units which resulted from the final analytical tables and syntaxonomy procedure consist of three classes, three orders, five alliances, four associations, nine communities, four subassociations, eleven subcommunities, thirteen varieties and nineteen facies
Impurity Scattering of Wave Packets on a Lattice
Creators: name: Kim, Wonkee
name: Covaci, L.
name: Marsiglio, F.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Quantum transport in a lattice is distinct from its counterpart in continuum media. Even a free wave packet travels differently in a lattice than in the continuum. We describe quantum scattering in a one dimensional lattice using three different formulations and illustrate characteristics of quantum transport such as resonant transmission. We demonstrate the real time propagation of a wave packet and its phase shift due to impurity configurations. Spin-flip scattering is also taken into account in a spin chain system. We show how individual spins in the chain evolve as a result of a spin-flip interaction between an incoming electron and a spin chain.
description: submitted to Phys. Rev. B
Life cycle decisions in Mycobacteriophage MPhalcon
Creators: name: Griffith, Alec
name: Raveena Mann
name: Spurling, Riley
name: Lund, Andrew
name: Krisanavane Reddi
name: Parker, Jordan Moberg
name: Freise, Amanda
Publisher: name: F1000 Research Limited
Year: 2019

description: Bacteriophages are the most abundant organism in the biosphere and are influential in soil ecosystems, affecting many biogeochemical cycles. Through horizontal gene transfer, temperate bacteriophages, which replicate via lytic or lysogenic life cycles, exchange genomic information with hosts. This affects bacteria-phage coevolution, genetic diversity, and microbial community structure. This study explored the conditions and parameters that influence lytic-lysogenic life cycle decisions of temperate mycobacteriophages, such as incubation at increasing temperatures and exposure to ultraviolet radiation, and analyzed genes directly and indirectly related to phage life cycle. This would promote greater understanding of phage propagation, and their influence in microbial soil communities and the biosphere as a whole. Temperate mycobacteriophage MPhalcon infects Mycobacterium smegmatis mc2155, and was directly isolated from soil in Venice, California, purified, amplified, and categorized as a Cluster E phage. Plaque assays that were incubated at temperatures ranging from 30˚C- 42˚C showed increased turbidity, and thus lysogeny, at higher incubation temperatures. Liquid lysogen cultures with MPhalcon that were exposed to ultraviolet radiation showed an increase in clear plaque morphologies, which indicated the induction of the lytic cycle. The genome of MPhalcon was sequenced and annotated, which revealed lytic genes, such as Lysin A and Lysin B, and lysogenic genes, such as integrase. There were unique genes in MPhalcon, possibly as the result of horizontal gene transfer, such as Lsr2, a DNA bridging protein found in Mycobacterium tuberculosis. These findings foster understanding of how life cycle decisions in temperate phage can motivate microbial soil community diversity and evolution.
Supplementary document for Ultra-Sensitive Temperature and Pressure Sensor Based on PDMS-based FPI and Vernier-effect - 6306927.pdf
Creators: name: Song, Jiao
name: Sun, Simei
name: Jiang, Chao
name: Chen, Ning
name: Jiang, Wenbo
name: Liu, Changning
name: Ren, Jie
name: Wang, Saiyu
Publisher: name: Optica Publishing Group
Year: 2023
Subjects: Uncategorized

description: Supplement 1
Hofstadter butterfly for a finite correlated system
Creators: name: Czajka, Katarzyna
name: Gorczyca, Anna
name: Maska, Maciej M.
name: Mierzejewski, Marcin
Publisher: name: arXiv
Year: 2007
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We investigate a finite two-dimensional system in the presence of external magnetic field. We discuss how the energy spectrum depends on the system size, boundary conditions and Coulomb repulsion. On one hand, using these results we present the field dependence of the transport properties of a nanosystem. In particular, we demonstrate that these properties depend on whether the system consists of even or odd number of sites. On the other hand, on the basis of exact results obtained for a finite system we investigate whether the Hofstadter butterfly is robust against strong electronic correlations. We show that for sufficiently strong Coulomb repulsion the Hubbard gap decreases when the magnetic field increases.
description: 7 pages, 5 figures, revtex
Charms of Strongly Interacting Conformal Gauge Mediation
Creators: name: Choi, Gongjun
name: Yanagida, Tsutomu T.
name: Yokozaki, Norimi
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: By extending a previously proposed conformal gauge mediation model, we construct a gauge-mediated SUSY breaking (GMSB) model where a SUSY-breaking scale, a messenger mass, the $μ$-parameter and the gravitino mass in a minimal supersymmetric (SUSY) Standard Model (MSSM) are all explained by a single mass scale, a R-symmetry breaking scale. We focus on a low scale SUSY-breaking scenario with the gravitino mass $m_{3/2}=\mathcal{O}(1){\rm eV}$, which is free from the cosmological gravitino problem and relaxes the fine-tuning of the cosmological constant. Both the messenger and SUSY-breaking sectors are subject to a hidden strong dynamics with the conformality above the messenger mass threshold (and hence the name of the model "strongly interacting conformal gauge mediation"). In our model, the Higgs B-term is suppressed and a large $\tanβ$ is predicted, resulting in the relatively light second CP-even Higgs and the CP-odd Higgs with a sizable production cross section. These Higgs bosons can be tested at future LHC experiments.
description: 8 pages, 2 figures, 1 table
A Framework for Real-time Traffic Trajectory Tracking, Speed Estimation, and Driver Behavior Calibration at Urban Intersections Using Virtual Traffic Lanes
Creators: name: Abdelhalim, Awad
name: Abbas, Montasir
name: Kotha, Bhavi Bharat
name: Wicks, Alfred
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: In a previous study, we presented VT-Lane, a three-step framework for real-time vehicle detection, tracking, and turn movement classification at urban intersections. In this study, we present a case study incorporating the highly accurate trajectories and movement classification obtained via VT-Lane for the purpose of speed estimation and driver behavior calibration for traffic at urban intersections. First, we use a highly instrumented vehicle to verify the estimated speeds obtained from video inference. The results of the speed validation show that our method can estimate the average travel speed of detected vehicles in real-time with an error of 0.19 m/sec, which is equivalent to 2% of the average observed travel speeds in the intersection of the study. Instantaneous speeds (at the resolution of 30 Hz) were found to be estimated with an average error of 0.21 m/sec and 0.86 m/sec respectively for free-flowing and congested traffic conditions. We then use the estimated speeds to calibrate the parameters of a driver behavior model for the vehicles in the area of study. The results show that the calibrated model replicates the driving behavior with an average error of 0.45 m/sec, indicating the high potential for using this framework for automated, large-scale calibration of car-following models from roadside traffic video data, which can lead to substantial improvements in traffic modeling via microscopic simulation.
Force spectroscopy with electromagnetic tweezers
Creators: name: Piccolo, Joseph G.
name: Harper, Joshua Mendez
name: Kovari, Dan
name: Dunlap, David
name: Finzi, Laura
Publisher: name: arXiv
Year: 2021
Subjects: subject: Biological Physics (physics.bio-ph)
subject: Applied Physics (physics.app-ph)
subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: Force spectroscopy using magnetic tweezers (MT) is a powerful method to probe the physical characteristics of single polymers. Typically, molecules are functionalized for specific attachment to a glass surface at one end and a micron-scale paramagnetic beads at the other. By applying an external magnetic field, multiple molecules can be stretched and twisted simultaneously without exposure to potentially damaging radiation. The majority of MT utilize moving permanent magnets to produce the forces on the beads (and the molecule under test). However, translating and rotating the permanent magnets may require expensive precision actuators, limits the rate at which force is changed, and may induce vibrations that disturb tether dynamics. Alternatively, the magnetic field can be produced through an electromagnet which allows much faster force modulation and eliminates motor-associated vibration. Here, we describe a low-cost quadrapolar electromagnetic tweezer design capable of manipulating DNA-tethered MyOne paramagnetic beads with forces of up to 20 pN. The solid-state nature of the generated B-field modulated along two axes is convenient for accessing the range of forces and torques relevant for studying the activity of DNA motor enzymes like polymerases and helicases. Our design specifically leverages technology available at an increasing number university maker spaces and student-run machine shops. Thus, our design is not only applicable to a wide range biophysical research questions, but also an accessible tool for undergraduate education.
description: 7 pages, 7 figures
The dynamics and timescales of static stall
Creators: name: Fouest, Sébastien Le
name: Deparday, Julien
name: Mulleners, Karen
Publisher: name: arXiv
Year: 2021
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: Airfoil stall plays a central role in the design of safe and efficient lifting surfaces. We typically distinguish between static and dynamic stall based on the unsteady rate of change of an airfoil's angle of attack. Despite the somewhat misleading denotation, the force and flow development of an airfoil undergoing static stall are highly unsteady and the boundary with dynamic stall is not clearly defined. We experimentally investigate the forces acting on a two-dimensional airfoil that is subjected to two manoeuvres leading to static stall: a slow continuous increase in angle of attack with a reduced pitch rate of 1.3e-4 and a step-wise increase in angle of attack from 14.2° to 14.8° within 0.04 convective times. We systematically quantify the stall reaction delay for many repetitions of these two manoeuvres. The onset of flow stall is marked by the distinct drop in the lift coefficient. The reaction delay for the slow continuous ramp-up manoeuvre is not influenced by the blade kinematics and its occurrence histogram is normally distributed around 32 convective times. The static reaction delay is compared with dynamic stall delays for dynamic ramp-up motions with reduced pitch rates ranging from 9e-4 to 0.14 and for dynamic sinusoidal pitching motions of different airfoils at higher Reynolds numbers up to 1e6. The stall delays for all conditions follows the same power law decrease from 32 convective times for the most steady case down to an asymptotic value of 3 for reduced pitch rates above 0.04. Static stall is not phenomenologically different than dynamic stall and is merely a typical case of stall for low pitch rates. Based on our results, we suggest that conventional measurements of the static stall angle and the static load curves should be conducted using a continuous and uniform ramp-up motion at a reduced frequency around 1e-4.
Data Enforced: An Exploratory Impact Analysis of Automated Speed Enforcement in the District of Columbia
Creators: name: Abdelhalim, Awad
name: Bailey, Linda
name: Dalphy, Emily
name: Raboy, Kelli
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computers and Society (cs.CY)
subject: FOS: Computer and information sciences

description: In 2015, the District of Columbia framed a Vision Zero mission and action plan, with a target of achieving zero traffic fatalities by 2024. This study examines the impacts of Automated Speed Enforcement (ASE) and its role in achieving the goals of Vision Zero. Independent datasets containing detailed information about traffic crashes, ASE camera locations, and citation records, and driving speeds across the District's streets were collected, combined, and analyzed to identify patterns and trends in crashes, speed limit violations, and speeding behavior before and after the ASE camera installation. The results of this exploratory analysis confirm the safety benefits of ASE systems in Washington, D.C. The study also provides a blueprint for the different means of evaluating the short-term impact of ASE systems using different data sources which can aid practitioners in better evaluating existing systems and support the decision-making process regarding future installations.
Scaled solar tracks and isochrones in a large region of the Z-Y plane I. From the ZAMS to the TP-AGB end for 0.15 - 2.5 Mo stars
Creators: name: Bertelli, G.
name: Girardi, L.
name: Marigo, P.
name: Nasi, E.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Tracks and isochrones have been computed in the range of initial masses 0.15 - 20 Mo for a grid of 39 chemical compositions with the metal content Z between 0.0001 and 0.070, and helium content Y between 0.23 and 0.46. The Padova stellar evolution code has been implemented with updated physics. New synthetic TP-AGB models allow the extension of stellar models and isochrones until the end of the thermal pulses along the AGB. Software tools for the bidimensional interpolation (in Y and Z) of the tracks have been tuned. This first paper presents tracks for low mass stars (from 0.15 to 2.5 Mo) with scaled-solar abundances and the corresponding isochrones from very old ages down to about 1 Gyr. Tracks and isochrones are made available in tabular form for the adopted grid of chemical compositions in the plane Z-Y. An interactive web interface will allow users to obtain isochrones of whatever chemical composition and also simulated stellar populations with different Y(Z) helium-to-metal enrichment laws.
description: 16 pages, 14 figures, accepted for publication in A&A
Inhomogeneity-induced enhancement of the pairing interaction in cuprates
Creators: name: Maska, Maciej M.
name: Sledz, Zaneta
name: Czajka, Katarzyna
name: Mierzejewski, Marcin
Publisher: name: arXiv
Year: 2007
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Scanning tunneling spectroscopy has recently discovered a positive correlation between the magnitude of the superconducting gap and positions of dopant oxygen atoms in Bi-based cuprates. We propose a microscopic mechanism that could be responsible for this effect. In particular, we demonstrate that the dopant-induced spatial variation of the atomic levels always enhances the superexchange interaction.
description: 4 pages, 5 figures, revtex