cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
A New Method for Estimating Starspot Lifetimes Based on Autocorrelation Functions
Creators: name: Basri, Gibor
name: Streichenberger, Tristan
name: McWard, Connor
name: Edmond, Lawrence
name: Tan, Joanne
name: Lee, Minjoo
name: Melton, Trey
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We present a method that utilizes autocorrelation functions from long-term precision broadband differential light curves to estimate the average lifetimes of starspot groups for two large sample of Kepler stars: stars with and without previously known rotation periods. Our method is calibrated by comparing the strengths of the first few normalized autocorrelation peaks using ensembles of models that have various starspot lifetimes. We find that we must mix models of short and long lifetimes together (in heuristically determined ratios) to align the models with the Kepler data. Our fundamental result is that short starspot group lifetimes (1-4 rotations) are implied when the first normalized peak is weaker than about 0.4, long lifetimes (15 or greater) are implied when it is greater than about 0.7, and in between are the intermediate cases. Rotational lifetimes can be converted to physical lifetimes if the rotation period is known. Stars with shorter rotation periods tend to have longer rotational (but not physical) spot lifetimes, and cooler stars tend to have longer physical spot lifetimes than warmer stars with the same rotation period. The distributions of the physical lifetimes are lognormal for both samples and generally longer in the first sample. The shorter lifetimes in the stars without known periods probably explain why their periods are difficult to measure. Some stars exhibit longer than average physical starspot lifetimes; their percentage drops with increasing temperature from nearly half at 3000K to nearly zero for hotter than 6000K.
description: 60 pages, 18 figures, refereed, to be published in ApJ
Pulsational instability of pre-main sequence models from accreting protostars. I. Constraining the input physics for accretion with spectroscopic parameters and stellar pulsations
Creators: name: Steindl, T.
name: Zwintz, K.
name: Barnes, T. G.
name: Muellner, M.
name: Vorobyov, E. I.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Context: The pre-main sequence evolution is often simplified by choosing classical initial models. These have large initial radii and sufficient uniform contraction to make them fully convective. Contrary to that, real stars are born as small protostellar seeds in collapsing molecular clouds and obtain their final mass by means of accretion. Aims: We aim to constrain the input physics of accretion on protostellar seeds with observed spectroscopic parameters and stellar pulsations of young stellar objects and pre-main sequence stars. Methods: We conducted a literature search for spectroscopic samples of young stellar objects and pre-main sequence stars including all previously known pulsators. The sample size of pulsating pre-main sequence stars is increased by analysing TESS observations and presenting discoveries in CoRoT data. We employ MESA and GYRE to calculate evolutionary tracks of accreting protostellar seeds in a constant accretion scenario, the subsequent pre-main sequence evolution, and their pulsation properties. The results are then compared with observations to constrain the input physics. Results: We discuss 16 formerly unknown pulsating pre-main sequence stars and candidates that are either of SPB, $δ$ Scuti,$γ$ Doradus or $δ$ Scuti - $γ$ Doradus hybrid type. We find that evolutionary tracks with a mass accretion rate of $5\times10^{-6} M_\odot/{\rm yr}$ and fraction of injected accretion energy of $β=0.1$ provide the best results in enveloping the spectroscopic parameters of pre-main sequence stars in a constant accretion scenario. The calculated instability regions constrain the atmospheric boundary conditions to Eddington Gray atmospheres; we discuss the future potential for additional constraints by instability regions that are dependent on radial order. We present a possible candidate for pulsations in M-type young stellar objects.
description: 21 pages plus 12 for the appendix, 17 figures plus 27 for the appendix, accepted for publication in Astronomy & Astrophysics
REGISTROS DE δ13C PRESERVADOS AO LONGO DOS ÚLTIMOS 2 MIL ANOS EM ESTALAGMITES DA AMÉRICA DO SUL
Creators: name: Novello, Valdir F.
name: Cruz, Francisco W.
Publisher: name: Zenodo
Year: 2020
Subjects: δ13C
estalagmites
cavernas
paleoclima
paleoambiente

description: RESUMO Devido a diversos fatores que controlam os valores de δ 13C em estalagmites que dificulta a sua interpretação, a maioria de estudos paleoclimáticos e paleoambientais com espeleotemas utilizam somente dados de δ 18O e negligenciam os valores de δ 13C dos registros. Esse é o caso para a maioria dos estudos desenvolvidos em cavernas da América do Sul, em que muitos registros de δ 18O cobrindo os últimos milênios foram publicados. Aqui nós, testamos a influência do hidroclima local, altitude, temperatura e mudanças no tipo de vegetação nos valores de δ 13C das estalagmites com o uso de um novo banco de dados compostos por registros isotópicos de carbono provenientes de várias localidades da América do Sul. Nossa análise sugere a predominância de plantas do tipo C3 ao longo dos últimos 2 mil anos para a maioria das áreas estudadas. Foi identificado que o hidroclima local é o principal responsável pela variação dos valores de δ 13C nas estalagmites seguido por efeitos menores causados pela temperatura. A maioria dos registros isotópicos mostrou correlação significativa entre os valores de δ 13C e δ 18O, indicando uma relação próxima entro o hidroclima local e processos convectivos do Sistema de Monção Sul Americana.
Quantum Billiards in Optical Lattices
Creators: name: Montangero, Simone
name: Frustaglia, Diego
name: Calarco, Tommaso
name: Fazio, Rosario
Publisher: name: arXiv
Year: 2008
Subjects: subject: Quantum Physics (quant-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We study finite two dimensional spin lattices with definite geometry (spin billiards) demonstrating the display of collective integrable or chaotic dynamics depending on their shape. We show that such systems can be quantum simulated by ultra-cold atoms in optical lattices and discuss how to identify their dynamical features in a realistic experimental setup. Possible applications are the simulation of quantum information tasks in mesoscopic devices.
Revealing asymmetrical dust distribution in the inner regions of HD 141569
Creators: name: Singh, Garima
name: Bhowmik, Trisha
name: Boccaletti, Anthony
name: Thébault, Philippe
name: Kral, Quentin
name: Milli, Julien
name: Mazoyer, Johan
name: Pantin, Eric
name: Olofsson, Johan
name: Boukrouche, Ryan
name: Di Folco, Emmanuel
name: Janson, Markus
name: Langlois, Maud
name: Maire, Anne Lise
name: Vigan, Arthur
name: Benisty, Myriam
name: Augereau, Jean-Charles
name: Perrot, Clement
name: Gratton, Raffaele
name: Henning, Thomas
name: Ménard, Francois
name: Rickman, Emily
name: Wahhaj, Zahed
name: Zurlo, Alice
name: Biller, Beth
name: Bonnefoy, Mickael
name: Chauvin, Gael
name: Delorme, Philippe
name: Desidera, Silvano
name: D'Orazi, Valentina
name: Feldt, Markus
name: Hagelberg, Janis
name: Keppler, Miriam
name: Kopytova, Taisiya
name: Lagadec, Eric
name: Lagrange, Anne-Marie
name: Mesa, Dino
name: Meyer, Michael
name: Rouan, Daniel
name: Sissa, Elena
name: Schmidt, Tobias
name: Jaquet, Marc
name: Fusco, Thierry
name: Pavlov, Alexei
name: Rabou, Patrick
Publisher: name: arXiv
Year: 2021
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: We obtained polarimetric differential imaging of a gas-rich debris disk around HD 141569A with SPHERE in the H-band to compare the scattering properties of the innermost ring at 44 au with former observations in total intensity with the same instrument. In polarimetric imaging, we observed that the intensity of the ring peaks in the south-east, mostly in the forward direction, whereas in total intensity imaging, the ring is detected only at the south. This noticeable characteristic suggests a non-uniform dust density in the ring. We implemented a density function varying azimuthally along the ring and generated synthetic images both in polarimetry and in total intensity, which are then compared to the actual data. We find that the dust density peaks in the south-west at an azimuthal angle of $220^{\circ} \sim 238^{\circ}$ with a rather broad width of $61^{\circ} \sim 127^{\circ}$. Although there are still uncertainties that remain in the determination of the anisotropic scattering factor, the implementation of an azimuthal density variation to fit the data proved to be robust. Upon elaborating on the origin of this dust density distribution, we conclude that it could be the result of a massive collision when we account for the effect of the high gas mass that is present in the system on the dynamics of grains. Using the outcome of this modelization, we further measured the polarized scattering phase function for the observed scattering angle between 33$^{\circ}$ and 147$^{\circ}$ as well as the spectral reflectance of the southern part of the ring between 0.98 $μ$m and 2.1 $μ$m. We tentatively derived the grain properties by comparing these quantities with MCFOST models and assuming Mie scattering. Our preliminary interpretation indicates a mixture of porous sub-micron sized astro-silicate and carbonaceous grains.
description: 21 pages, 18 figures, Accepted for publication in Astronomy & Astrophysics journal
TELECONEXÕES CLIMÁTICAS ENTRE A ALTA LATITUDE DO HEMISFÉRIO NORTE E A ZONA DE CONVERGÊNCIA INTERTROPICAL DURANTE O ÚLTIMO PERÍODO GLACIAL
Creators: name: Ramirez, Verónica M.
name: Cruz, Francisco W.
name: Cheng, Hai
name: Bernal, Juan Pablo
name: Du, Wenjing
name: Ampuero, Angela
name: Vuille, Mathias
Publisher: name: Zenodo
Year: 2020
Subjects: Paleoclimate, , , ,
Ultimo Periodo Glacial
Espeleotemas
ITCZ
Trópico

description: RESUMO Um grande paradigma em climatologia sustenta que as mudanças na posição média da Zona de Convergência Intertropical (ITCZ) foram o mecanismo climático dominante no controle das chuvas nos trópicos durante o último período glacial. Mudanças em escala milenar nas chuvas relacionadas ao ITCZ são documentadas em detalhes em locais como a Bacia de Cariaco, no norte da América do Sul. No entanto, as mudanças de longo prazo nas chuvas relacionadas ao ITCZ permanecem indefinidas, além de não ter uma ótima definição da posição nos eventos milenares. Aqui, apresentamos uma nova reconstrução de paleoprecipitação baseada no registro de espeleotemas de alta resolução  18O do nordeste da Colômbia, que abrange a maior parte do último ciclo glacial. Nossos resultados mostram que a precipitação no ITCZ varia em concordância com as condições climáticas extratropicais do Hemisfério Norte (NH), em resposta às condições de contorno glaciais. Temperaturas mais frias e o crescimento da camada de gelo no NH empurraram o ITCZ para o sul, aumentando as chuvas sobre a Colômbia, indicando que o ITCZ nunca foi localizado ao sul da Colômbia em resposta ao forçamento orbital nem milenar dos eventos Greenland Stadiais (GS) e Interstadiais (GS).
The Use of Remote Sensing Technology for Evaluation of Flood Damages: A Review Literature
Creators: name: Chattichai Waisurasingha
Publisher: name: Faculty of Engineering, Khon Kaen Univeristy
Year: 2011
Subjects: Flooded Damage Assessment, Remote Sensing Technique, Flood Delineation, Flood Hazard Intensity,Flood Depth

description: 3, 38, KKU Engineering Journal
Unexplained Spectral Phenomena in the Interstellar Medium: an introduction
Creators: name: Kwok, Sun
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: There exists a number of astronomical spectral phenomena that have remained unidentified after decades of extensive observations. The diffuse interstellar bands, the 220 nm feature, unidentified infrared emission bands, extended red emissions, and 21 and 30 $μ$m emission features are seen in a wide variety of astrophysical environments. The strengths of these features suggest that they originate from chemical compounds made of common elements, possibly organic in nature. The quest to understand how such organic materials are synthesized and distributed across the Galaxy represents a major challenge to our understanding of the chemical content of the Universe.
On knot Floer homology in double branched covers
Creators: name: Roberts, Lawrence P.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Geometric Topology (math.GT)
subject: FOS: Mathematics

description: Let L be a link in an thickened annulus. We specify the embedding of this annulus in the three sphere, and consider its complement thought of as the axis to L. In the right circumstances this axis lifts to a null-homologous knot in the double branched cover of the three sphere, branched over the embedded copy of L. This paper shows that the knot Floer homology of this lift, with mod 2 coefficients, can be computed from a spectral sequence starting at a type of Khovanov homology already described by Asaeda, Przytycki, and Sikora. We extend the known results about this type of Khovanov homology, and use it to provide a very simple explanation of the case when L is alternating for the obvious projection.
description: Due to an error in section 8, the results on the contact element have been weakened
Zoila glomerabilis Darragh 2011, sp. nov.
Creators: name: Darragh, Thomas A.
Publisher: name: Zenodo
Year: 2011
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Littorinimorpha
Cypraeidae
Zoila
Zoila glomerabilis

description: Zoila glomerabilis sp. nov.
Figures 6F–H, 7A–F
Description. Shell of large size for genus, solid, globosely pyriform, abruptly contracted anteriorly to short, narrow anterior canal. Spire projecting slightly, almost entirely enveloped by last whorl, covered with thick callus. Posterior canal short, deeply incised, reflexed to the left. Anterior canal deeply incised, with rounded sides, reflexed dorsally, supported laterally by very short, narrow flanges. Aperture sinuous, slightly widened and sloping steeply inwards before anterior canal. Outer lip with 28–36 teeth extending along entire lip; inner lip with 15–32 teeth extending along entire lip on most specimens; weaker posteriorly on some specimens and on few specimens extending only along half of lip. Fossula well developed, broad, relatively deeply depressed, bounded anteriorly by weak terminal ridge.
Dimensions.
Type locality. Lower beds of section south of Fishermen’s Steps, Bird Rock Cliffs, Torquay, Victoria. Jan Juc Formation.
Type material. Holotype P14515, F.A. Cudmore collection; paratype P308740, presented S. F. Colliver, 16 January 1962; paratype P315526, presented C. Goudey, 2009.
Time range. Janjukian, Late Oligocene–Longfordian, Early Miocene.
Occurrence and material. Janjukian: Jan Juc Formation. At sea level, Bird Rock, Torquay (P304422, one specimen); Half Moon Bay, Torquay (P315526, one specimen); Torquay (P308706, P304432, P304423, seven specimens); Geological Survey of Victoria locality Ad 22, Bird Rock, Torquay (P308717, one specimen).
Longfordian: Fishing Point Marl. ‘Picnic bed’, Horden Vale (P308741-2, two specimens).
Remarks. This species is very similar in morphology to Z. dolichorhyncha sp. nov. but differs in that it is more globose, has a shorter anterior canal and tapers more abruptly towards the anterior. Zoila glomerabilis bears some resemblance to Z. venusta (Sowerby), Recent, Western Australia, but is more globose and has a prominent anterior canal lacking in Z. venusta. The fossula is very similar to that in Z. venusta, but not quite as elongate.
Etymology. Latin, glomerabilis, round.
description: Published as part of Darragh, Thomas A., 2011, A revision of the Australian fossil species of Zoila (Gastropoda: Cypraeidae), pp. 1-28 in Memoirs of Museum Victoria 68 on pages 9-11, DOI: 10.24199/j.mmv.2011.68.01, http://zenodo.org/record/10665999
General K=-1 Friedman-Lemaître models and the averaging problem in cosmology
Creators: name: Reiris, Martin
Publisher: name: arXiv
Year: 2007
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We introduce the notion of general K=-1 Friedman-Lemaître (compact) cosmologies and the notion of averaged evolution by means of an averaging map. We then analyze the Friedman-Lemaître equations and the role of gravitational energy on the universe evolution. We distinguish two asymptotic behaviors: radiative and mass gap. We discuss the averaging problem in cosmology for them through precise definitions. We then describe in quantitative detail the radiative case, stressing on precise estimations on the evolution of the gravitational energy and its effect in the universe's deceleration. Also in the radiative case we present a smoothing property which tells that the long time H^{3} x H^{2} stability of the flat K=-1 FL models implies H^{i+1} x H^{i} stability independently of how big the initial state was in H^{i+1} x H^{i}, i.e. there is long time smoothing of the space-time. Finally we discuss the existence of initial "big-bang" states of large gravitational energy, showing that there is no mathematical restriction to assume it to be low at the beginning of time.
description: Revised version. 32 pages, 1 figure
Maximum Likelihood Fitting of Tidal Streams With Application to the Sagittarius Dwarf Tidal Tails
Creators: name: Cole, Nathan
name: Newberg, Heidi Jo
name: Magdon-Ismail, Malik
name: Desell, Travis
name: Dawsey, Kristopher
name: Hayashi, Warren
name: Xinyang
name: Liu
name: Purnell, Jonathan
name: Szymanski, Boleslaw
name: Varela, Carlos
name: Willett, Benjamin
name: Wisniewski, James
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present a maximum likelihood method for determining the spatial properties of tidal debris and of the Galactic spheroid. With this method we characterize Sagittarius debris using stars with the colors of blue F turnoff stars in SDSS stripe 82. The debris is located at (alpha, delta, R) = (31.37 deg +/- 0.26 deg, 0.0 deg, 29.22 +/- 0.20 kpc), with a (spatial) direction given by the unit vector < -0.991 +/- 0.007 kpc, 0.042 +/- 0.033 kpc, 0.127 +/- 0.046 kpc >, in Galactocentric Cartesian coordinates, and with FWHM = 6.74 +/- 0.06 kpc. This 2.5 degee-wide stripe contains 0.9% as many F turnoff stars as the current Sagittarius dwarf galaxy. Over small spatial extent, the debris is modeled as a cylinder with a density that falls off as a Gaussian with distance from the axis, while the smooth component of the spheroid is modeled with a Hernquist profile. We assume that the absolute magnitude of F turnoff stars is distributed as a Gaussian, which is an improvement over previous methods which fixed the absolute magnitude at Mg0 = 4.2. The effectiveness and correctness of the algorithm is demonstrated on a simulated set of F turnoff stars created to mimic SDSS stripe 82 data, which shows that we have a much greater accuracy than previous studies. Our algorithm can be applied to divide the stellar data into two catalogs: one which fits the stream density profile and one with the characteristics of the spheroid. This allows us to effectively separate tidal debris from the spheroid population, both facilitating the study of the tidal stream dynamics and providing a test of whether a smooth spheroidal population exists.
description: 50 pages, 8 figures, 5 tables. Accepted for publication into the Astrophysical Journal
Revisiting Critical Vortices in Three-Dimensional SQED
Creators: name: Olmez, S.
name: Shifman, M.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider renormalization of the central charge and the mass of the ${\cal N}=2$ supersymmetric Abelian vortices in 2+1 dimensions. We obtain ${\cal N}=2$ supersymmetric theory in 2+1 dimensions by dimensionally reducing the ${\cal N}=1$ SQED in 3+1 dimensions with two chiral fields carrying opposite charges. Then we introduce a mass for one of the matter multiplets without breaking N=2 supersymmetry. This massive multiplet is viewed as a regulator in the large mass limit. We show that the mass and the central charge of the vortex get the same nonvanishing quantum corrections, which preserves BPS saturation at the quantum level. Comparison with the operator form of the central extension exhibits fractionalization of a global U(1) charge; it becomes 1/2 for the minimal vortex. The very fact of the mass and charge renormalization is due to a "reflection" of an unbalanced number of the fermion and boson zero modes on the vortex in the regulator sector.
description: 24 pages, 2 figures Minor modifications, reference added
Theory of light-induced current in molecular-tunneling junctions excited with intense shaped pulses
Creators: name: Fainberg, B. D.
name: Jouravlev, M.
name: Nitzan, A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: A theory for light-induced current by strong optical pulses in molecular-tunneling junctions is described. We consider a molecular bridge represented by its highest occupied and lowest unoccupied levels, HOMO and LUMO, respectively. We take into account two types of couplings between the molecule and the metal leads: electron transfer that gives rise to net current in the biased junction and energy transfer between the molecule and electron-hole excitations in the leads. Using a Markovian approximation, we derive a closed system of equations for the expectation values of the relevant variables: populations and molecular polarization that are binary, and exciton populations that are tetradic in the annihilation and creation operators for electrons in the molecular states. We have proposed an optical control method using chirped pulses for enhancing charge transfer in unbiased junctions where the bridging molecule is characterized by a strong charge-transfer transition. An approximate analytical solution of the resulting dynamical equation is supported by a full numerical solution. When energy transfer between the molecule and electron-hole excitations in the leads is absent, the optical control problem for inducing charge transfer with linearly chirped pulse can be reduced to the Landau-Zener transition to a decaying level. When chirp is fast with respect to the rate of the electron transfer, the Landau theory is recovered. The proposed control mechanism is potentially useful for developing novel opto-electronic single-electron devices with optical gating based on molecular nanojunctions.
description: 14 pages, 7 figures; submitted to PRB
The Effect of Support Measures on Involvement in Technology Transfer
Creators: name: Kochenkova, Anna <1982>
Publisher: name: Alma Mater Studiorum - Università di Bologna
Year: 2014
Subjects: SECS-P/08 Economia e gestione delle imprese

description: The present PhD dissertation is dedicated to the general topic of knowledge transfer from academia to industry and the role of various measures at both institutional and university levels in support of commercialization of university research. The overall contribution of the present dissertation work refers to presenting an in-depth and comprehensive analysis of the main critical issues that currently exist with regard to commercial exploitation of academic research, while providing evidence on the role of previously underexplored areas (e.g. strategic use of academic patents; female academic patenting) in a general debate on the ways to successful knowledge transfer from academia to industry.
The first paper, included in the present PhD dissertation, aims to address this gap by developing a taxonomy of literature, based on a comprehensive review of the existing body of research on government measures in support of knowledge transfer from academia to industry. The results of the review reveal that there is a considerable gap in the analysis of the impact and relative effectiveness of the public policy measures, especially in what regards the measures aimed at building knowledge and expertise among academic faculty and technology transfer agents. 
The second paper, presented as a part of the dissertation, focuses on the role of interorganizational collaborations and their effect on the likelihood of an academic patent to remain unused, and points to the strategic management of patents by universities.  
In the third paper I turn to the issue of female participation in patenting and commercialization; in particular, I find evidence on the positive role of university and its internal support structures  in closing the gender gap in female academic patenting. 
The results of the research, carried out for the present dissertation, provide important implications for policy makers in crafting measures to increase the efficient use of university knowledge stock.
Universal low-temperature behavior of the CePd_{1-x}Rh_x ferromagnet
Creators: name: Shaginyan, V. R.
name: Popov, K. G.
name: Stephanovich, V. A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The heavy-fermion metal CePd_{1-x}Rh_x evolves from ferromagnetism at x=0 to a non-magnetic state at some critical concentration x_c. Utilizing the quasiparticle picture and the concept of fermion condensation quantum phase transition (FCQPT), we address the question about non-Fermi liquid (NFL) behavior of ferromagnet CePd_{1-x}Rh_x and show that it coincides with that of both antiferromagnet YbRh_2(Si_{0.95}Ge_{0.05})_2 and paramagnet CeRu_2Si_2 and CeNi_2Ge_2. We conclude that the NFL behavior being independent of the peculiarities of specific alloy, is universal, while numerous quantum critical points assumed to be responsible for the NFL behavior of different HF metals can be well reduced to the only quantum critical point related to FCQPT.
description: 6 pages, 7 figures
Varieties with Definable Factor Congruences
Creators: name: Terraf, Pedro Sánchez
name: Vaggione, Diego J.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Logic (math.LO)
subject: FOS: Mathematics
subject: 08B05; 03C40

description: We study direct product representations of algebras in varieties. We collect several conditions expressing that these representations are "definable" in a first-order-logic sense, among them the concept of Definable Factor Congruences (DFC). The main results are that DFC is a Mal'cev property and that it is equivalent to all other conditions formulated; in particular we prove that V has DFC if and only if V has 0&1 and Boolean Factor Congruences. We also obtain an explicit first order definition of the kernel of the canonical projections via the terms associated to the Mal'cev condition for DFC, in such a manner it is preserved by taking direct products and direct factors. The main tool is the use of "central elements," which are a generalization of both central idempotent elements in rings with identity and neutral complemented elements in a bounded lattice.
Perspectives on the use of sucralose in technologies of foods for patients with II type diabetes
Creators: name: Gubsky, Sergey
name: Aksonova, Olena
name: Toryanik, Dmitro
name: Kot, Sergiy
name: Sulima, Oksana
Publisher: name: Zenodo
Year: 2021
Subjects: sucralose
diabet
dietic food
sweeteners
sucrose
obesity

description: The analysis of statistics on the incidence of the population of the whole world and Ukraine, in particular, diabetes mellitus. The conclusion is drawn on the need to optimize the nutrition of both healthy people and people with certain pathologies. One of such innovative solutions is the introduction of low-calorie safe sweeteners, both of natural origin and synthesized artificially, into existing technological processes. The prospects of using highly effective sweeteners, in particular sucralose, in food technology for type II diabetes patients are analyzed. It has been shown that the use of highly effective sweeteners, in particular sucralose, is a way to reduce calorie intake by counting the complete or partial replacement of sucrose in many foods. The dietary nature that such products have can be especially useful in the control and treatment of type II diabetes mellitus and obesity.
The Impact Of Inward Licensing On New Venture’s Performance.
Is inward licensing a winning strategy?
Creators: name: Marzano, Maria Azzurra <1986>
Publisher: name: Alma Mater Studiorum - Università di Bologna
Year: 2014
Subjects: SECS-P/08 Economia e gestione delle imprese

description: The original idea of  the thesis draws on interrelated assumptions: 1) among the tools used, in the markets for technology, for the acquisition of external knowledge, the licensing agreements are acknowledged as one of the most important contractual mechanisms; 2) the liabilities of newness and the liabilities of smallness force new venture to strongly rely on  external knowledge sources. Albeit the relevance of this topic, little attention has been paid so far to its investigation, especially in the licensing context; 3) nowadays there is an increasing trend in licensing practices, but the literature on markets for technology focuses almost exclusively on the incentives and rationales that foster  firms’ decisions to trade their technologies, under-investigating the role of the acquiring firm, the licensee, overlooking the demand side of the market. Therefore, the thesis investigates the inward licensing phenomenon within the context of new ventures. The main questions that new venture licensee has to address if it decides to undertake an inward licensing strategy, can be summarized as follows:
1)	Is convenient for a new venture to choose, as initial technology strategy, the implementation of an inward licensing ? 
2)	Does this decision affect its survival probabilities? 
3)	Does the age, at which a new venture becomes a licensee, affect its innovative capabilities? Is it better to undertake a licensing-in strategy soon after founding or to postpone this strategy until the new venture has accumulated significant resources?
The findings suggest that new ventures licensees survive less than their non-licensee counterparts; the survival rates are directly connected to the time taken by firms to reach the market;being engaged in licensing-in deals some years after its inception allows a new venture licensee to increase its subsequent capacity to produce innovations.
A comment on the properties of the matter flow through the first Langrangian point
Creators: name: Ziolkowski, Janusz
name: Zdziarski, Andrzej A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We analyse properties of the mass outflow from the Roche-lobe filling component of a semi-detached binary system. We follow the approaches published by Paczyński \& Sienkiewicz and by Lubow \& Shu, which we compare with other simplified approaches. We find that the density of the flow at $L_1$ is orders of magnitude lower than the density on the same equipotential but away from $L_1$. Furthermore, the effective cross section of the flow, after averaging over its profile of the momentum density, is much lower than some published estimates done without accounting for the averaging. Thus, the use of some simplified formulae for the density and the flow cross section can lead to overestimates of the accretion rate and of the mass contained in the $L_1$ regions by very large factors unless they are supported by simultaneous integrations of the equations of stellar structure for the outer layers of the donor.
description: MNRAS, in press
Bypassing Cowling's theorem in axisymmetric fluid dynamos
Creators: name: Gissinger, Christophe
name: Dormy, Emmanuel
name: Fauve, Stephan
Publisher: name: arXiv
Year: 2008
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: We present a numerical study of the magnetic field generated by an axisymmetrically forced flow in a spherical domain. At small enough Reynolds number, Re, the flow is axisymmetric and generates an equatorial dipole above a critical magnetic Reynolds number Rmc . The magnetic field thus breaks axisymmetry, in agreement with Cowling's theorem. This structure of the magnetic field is however replaced by a dominant axial dipole when Re is larger and allows non axisymmetric fluctuations in the flow. We show here that even in the absence of such fluctuations, an axial dipole can also be generated, at low Re, through a secondary bifurcation, when Rm is increased above the dynamo threshold. The system therefore always find a way to bypass the constraint imposed by Cowling's theorem. We understand the dynamical behaviors that result from the interaction of equatorial and axial dipolar modes using simple model equations for their amplitudes derived from symmetry arguments.
description: 4 pages, 6 figures
Eco-evolutionary dynamics of cooperation in the presence of policing
Creators: name: Chowdhury, Sayantan Nag
name: Kundu, Srilena
name: Banerjee, Jeet
name: Perc, Matjaž
name: Ghosh, Dibakar
Publisher: name: arXiv
Year: 2021
Subjects: subject: Populations and Evolution (q-bio.PE)
subject: Physics and Society (physics.soc-ph)
subject: FOS: Biological sciences
subject: FOS: Physical sciences

description: Ecology and evolution are inherently linked, and studying a mathematical model that considers both holds promise of insightful discoveries related to the dynamics of cooperation. In the present article, we use the prisoner's dilemma (PD) game as a basis for long-term apprehension of the essential social dilemma related to cooperation among unrelated individuals. We upgrade the contemporary PD game with an inclusion of evolution-induced act of punishment as a third competing strategy in addition to the traditional cooperators and defectors. In a population structure, the abundance of ecologically-viable free space often regulates the reproductive opportunities of the constituents. Hence, additionally, we consider the availability of free space as an ecological footprint, thus arriving at a simple eco-evolutionary model, which displays fascinating complex dynamics. As possible outcomes, we report the individual dominance of cooperators and defectors as well as a plethora of mixed states, where different strategies coexist followed by maintaining the diversity in a socio-ecological framework. These states can either be steady or oscillating, whereby oscillations are sustained by cyclic dominance among different combinations of cooperators, defectors, and punishers. We also observe a novel route to cyclic dominance where cooperators, punishers, and defectors enter a coexistence via an inverse Hopf bifurcation that is followed by an inverse period doubling route.
The role of the stress trap in polariton quasiequilibrium condensation in GaAs microcavities
Creators: name: Balili, R.
name: Nelsen, B.
name: Snoke, D. W.
name: Pfeiffer, L.
name: West, K.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: Recent experiments have shown several effects indicative of Bose-Einstein condensation in polaritons in GaAs-based microcavity structures when a harmonic potential trap for the two-dimensional polaritons is created by applied stress. These effects include both real-space and momentum-space narrowing, first-order coherence, and onset of linear polarization above a particle density threshold. Similar effects have been seen in systems without traps, raising the question of how important the role of the trap is in these experiments. In this paper we present results for both trapped conditions and resonant, non-trapped conditions in the same sample. We find that the results are qualitatively different, with two distinct types of transitions. At low density in the trap, the polaritons remain in the strong-coupling regime while going through the threshold for onset of coherence; at higher density, there is a different threshold behavior which occurs with weak coupling and can be identified with lasing; this transition occurs both with and without a trap.
Self-similar stable processes arising from high-density limits of occupation times of particle systems
Creators: name: Bojdecki, Tomasz
name: Gorostiza, Luis G.
name: Talarczyk, Anna
Publisher: name: arXiv
Year: 2007
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60G52, 60G18, 60F17, 60J80

description: We extend results on time-rescaled occupation time fluctuation limits of the $(d,α, β)$-branching particle system $(0α/ β$ only, since the particle system becomes locally extinct if $d\le α/ β$. In this paper we show that by introducing high density of the initial Poisson configuration, limits are obtained for all dimensions, and they coincide with the previous ones if $d>α/β$. We also give high-density limits for the systems with finite intensity measures (without high density no limits exist in this case due to extinction); the results are different and harder to obtain due to the non-invariance of the measure for the particle motion. In both cases, i.e., Lebesgue and finite intensity measures, for low dimensions ($d
description: 28 pages
Zoila dolichorhyncha Darragh 2011, sp. nov.
Creators: name: Darragh, Thomas A.
Publisher: name: Zenodo
Year: 2011
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Littorinimorpha
Cypraeidae
Zoila
Zoila dolichorhyncha

description: Zoila dolichorhyncha sp. nov.
Figures 8A–F, 9C–E
Description. Shell of large size for genus, solid, pyriform, somewhat humped posteriorly and tapering anteriorly, of six teleoconch whorls. Spire projecting slightly, almost enveloped by last whorl, covered with thick callus. Protoconch of one smooth whorl, not differentiated from teleoconch whorls, coiled with the axis of the shell. Posterior canal short, deeply incised, reflexed to left. Anterior canal deeply incised, with rounded sides, reflexed dorsally, supported laterally by short, narrow flanges. Aperture sinuous, slightly widened and sloping steeply inwards before anterior canal; outer lip with 23–33 teeth extending along entire lip, on some specimens becoming very weak posteriorly; inner lip with 3–11 teeth (generally fewer than 10) present on anterior third of lip. Fossula well developed, broad, relatively deeply depressed, bounded anteriorly by weak terminal ridge.
Dimensions.
Type locality. Lower bed, Table Cape, Wynyard, Tasmania, (i.e. PL3028 lower bed in cliff between Fossil Bluff and l. 5 km northwest towards Table Cape, Wynyard, Tasmania, Table Cape 930630). Freestone Cove Sandstone, Early Miocene, early Longfordian.
Type material. Holotype P14514, purchased R.N. Atkinson, 8 May 1911; paratypes P304417-8, purchased R.N. Atkinson, 15 January 1910.
Time range. Longfordian, Early Miocene
Occurrence and material. Table Cape (P2644, P14618, P2766- 2770, P14595-6, P304417, P304449-50, 11 specimens); Crassatella bed, Fossil Bluff (P304440, one specimen); lower bed, Table Cape (P308708, P304431, P304433, seven specimens).
Remarks. This species has been mistaken for Zoila platypyga (McCoy) and recorded as such in lists of fossils from Table Cape published by Johnston (1888, p. 262) and Pritchard (1896, p. 106). It probably evolved from Z. glomerabilis sp. nov., from which it differs by being pyriform with a tapering anterior rather than being globose. Zoila glomerabilis has a uniformly rounded dorsum, whereas Z. dolichorhyncha sp. nov. has a dorsum humped posteriorly.
Etymology. Greek, dolichos, long; rhynchos, snout.
description: Published as part of Darragh, Thomas A., 2011, A revision of the Australian fossil species of Zoila (Gastropoda: Cypraeidae), pp. 1-28 in Memoirs of Museum Victoria 68 on pages 11-14, DOI: 10.24199/j.mmv.2011.68.01, http://zenodo.org/record/10665999
Free fermion resolution of supergroup WZNW models
Creators: name: Quella, Thomas
name: Schomerus, Volker
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Mathematical Physics (math-ph)
subject: Quantum Algebra (math.QA)
subject: Representation Theory (math.RT)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: Extending our earlier work on PSL(2|2), we explain how to reduce the solution of WZNW models on general type I supergroups to those defined on the bosonic subgroup. The new analysis covers in particular the supergroups GL(M|N) along with several close relatives such as PSL(N|N), certain Poincare supergroups and the series OSP(2|2N). This remarkable progress relies on the use of a special Feigin-Fuchs type representation. In preparation for the field theory analysis, we shall exploit a minisuperspace analogue of a free fermion construction to deduce the spectrum of the Laplacian on type I supergroups. The latter is shown to be non-diagonalizable. After lifting these results to the full WZNW model, we address various issues of the field theory, including its modular invariance and the computation of correlation functions. In agreement with previous findings, supergroup WZNW models allow to study chiral and non-chiral aspects of logarithmic conformal field theory within a geometric framework. We shall briefly indicate how insights from WZNW models carry over to non-geometric examples, such as e.g. the W(p) triplet models.
description: 47 pages
Noncommutative gravity, a `no strings attached' quantum-classical duality, and the cosmological constant puzzle
Creators: name: Singh, T. P.
Publisher: name: arXiv
Year: 2008
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: There ought to exist a reformulation of quantum mechanics which does not refer to an external classical spacetime manifold. Such a reformulation can be achieved using the language of noncommutative differential geometry. A consequence which follows is that the `weakly quantum, strongly gravitational' dynamics of a relativistic particle whose mass is much greater than Planck mass is dual to the `strongly quantum, weakly gravitational' dynamics of another particle whose mass is much less than Planck mass. The masses of the two particles are inversely related to each other, and the product of their masses is equal to the square of Planck mass. This duality explains the observed value of the cosmological constant, and also why this value is nonzero but extremely small in Planck units.
description: 7 pages. Second Prize in Gravity Research Foundation Essay Competition, 2008. Two paragraphs added to original essay to enhance clarity. To appear in Gen. Rel. Grav
Observation of half-integer quantum Hall effect in single-layer graphene using pulse magnet
Creators: name: Masubuchi, Satoru
name: Suga, Ken-ichi
name: Ono, Masashi
name: Kindo, Koichi
name: Takeyama, Shojiro
name: Machida, Tomoki
Publisher: name: arXiv
Year: 2008
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We report magnetotransport measurements on a single-layer graphene in pulsed magnetic fields up to $B$ = 53 T. With either electron- or hole-type charge carriers, the Hall resistance $R_{H}$ is quantized into $R_{H}$ = $(h/e^2)ν^{-1}$ with $ν$ = $\pm$2, $\pm$6, and $\pm$10, which demonstrates the observation of half-integer quantum Hall effect (QHE). At $B$ = 50 T, the half-integer QHE is even observed at room temperature in spite of a conventional carrier mobility $μ$ = 4000 cm$^2$/Vs.
description: 10 pages, 4 figures, accepted for publication in J. Phys. Soc. Jpn. (Letter)
Learning and evaluation without access to schools during COVID-19
Creators: name: Stefansson, Gunnar
name: Jonsdottir, Anna Helga
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computers and Society (cs.CY)
subject: Applications (stat.AP)
subject: FOS: Computer and information sciences

description: The tutor-web drilling system is designed for learning so there are typically no limits on the number of attempts at improving performance. This system is used at multiple schools and universities in Iceland and Kenya, mostly for mathematics and statistics. Students earn SmileyCoin, a cryptocurrency, while studying. In Iceland the system has typically been used by students who use their own devices to solve homework assignments during the semester, accessing the Internet-based tutor-web at http://tutor-web.net. These students typically take final exams on paper at the end of the semester. In Kenya the system is a part of a plan to enhance mathematics education using educational technology, organised by the Smiley Charity with the African Maths Initiative. This has been done by donating servers running the tutor-web to schools and tablets to students. Typically these schools do not have Internet access so the cryptocurrency can not be used. Innovative redesign was needed during COVID-19 in spring, 2020, since universities in Iceland were not able to host in-house finals and schools in Kenya were closed so tablets could not be donated directly to students. Remote finals were held in Iceland but the implementation was largely in the hands of the instructors. In Kenya, community libraries remained open and became a place for students to come in to study. Innovations included using the tutor-web as a remote drilling system in place of final exams in a large undergraduate course in statistics and donating tablets to libraries in Kenya. These libraries all have access to the Internet and the students have therefore been given the option to purchase the tablet using their SmileyCoin. This paper describes these implementations and how this unintended experiment will likely affect the future development and use of the tutor-web in both countries.
Entropy of (2+1)-dimensional de Sitter black hole to all orders in the Planck length
Creators: name: Kim, Yong-Wan
name: Park, Young-Jai
Publisher: name: arXiv
Year: 2007
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We calculate the statistical entropy of a scalar field on the background of (2+1)-dimensional de Sitter space without an artificial cutoff considering corrections to all orders in the Planck length from a generalized uncertainty principle (GUP) on the quantum state density. The desired entropy proportional to the horizon perimeter is obtained.
description: 10 pages, two references added
On the limited amplitude resolution of multipixel Geiger-mode APDs
Creators: name: Stoykov, A.
name: Musienko, Y.
name: Kuznetsov, A.
name: Reucroft, S.
name: Swain, J.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: The limited number of active pixels in a Geiger-mode Avalanche Photodiode (G-APD) results not only in a non-linearity but also in an additional fluctuation of its response. Both these effects are taken into account to calculate the amplitude resolution of an ideal G-APD, which is shown to be finite. As one of the consequences, the energy resolution of a scintillation detector based on a G-APD is shown to be limited to some minimum value defined by the number of pixels in the G-APD.
description: 5 pages, 3 figures