4,530 research outputs found

    Anomalous response of superconducting titanium nitride resonators to terahertz radiation

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    We present an experimental study of KIDs fabricated of atomic layer deposited TiN films, and characterized at radiation frequencies of 350350~GHz. The responsivity to radiation is measured and found to increase with increasing radiation powers, opposite to what is expected from theory and observed for hybrid niobium titanium nitride / aluminium (NbTiN/Al) and all-aluminium (all-Al) KIDs. The noise is found to be independent of the level of the radiation power. The noise equivalent power (NEP) improves with higher radiation powers, also opposite to what is observed and well understood for hybrid NbTiN/Al and all-Al KIDs. We suggest that an inhomogeneous state of these disordered superconductors should be used to explain these observations

    Seletividade de produtos fitossanitários utilizados na cultura da soja para pupas de Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae).

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    O objetivo do trabalho foi avaliar o efeito de produtos fitossanitários sobre pupas de Trichogramma pretiosum. Foram conduzidos três bioensaios em delineamento inteiramente casualizado com 11 tratamentos e cinco repetições. Em cada repetição, ovos de Anagasta kuehniella (Zeller, 1879) (Lepidoptera: Pyralidae) foram utilizados como hospedeiro alternativo, sendo aderidos em cartelas de cartolina de 1 cm2 com solução de goma arábica à 40% e oferecidos para o parasitismo por 24h. Após 168-192h do parasitismo, quando os parasitoides estavam na fase de pupa, as cartelas foram mergulhadas por cinco segundos nos tratamentos testados. Avaliou-se a sobrevivência dos indivíduos tratados e a redução na emergência dos parasitoides foi classificada segundo as normas da IOBC. Os inseticidas flufenoxurom (Cascade®) 10, diflubenzurom (Dimilin®) 20 e metoxifenozide (Intrepid 240SC®) 21,6 e 36 g i.a. ha-1 foram classificados como inócuos. Permetrina (Valon 384 CE®) 49,92; betaciflutrina 12,5 + imidacloprido 100 (Connect®) e gama-cialotrina (Stallion 150SC®) 3,75 g i.a. ha-1 foram levemente nocivos. Clorpirifós (Lorban 480BR®) 384 e espinosade (Tracer®) 24 g i.a. ha-1 foram moderadamente nocivos. Os herbicidas glifosato 720 + imazetapir 90 (Alteza®); s-metolacloro (Dual Gold®) 1920; flumioxazina (Flumyzin 500®) 60; clomazona (Gamit®) 1000; glifosato 2880 (Gliz 480SL®); dicloreto de paraquate 600 + diurom 300 (Gramocil®); glifosato 1200 (Roundup Ready®); foram classificados como inócuos e os herbicidas 2,4-D (DMA 806BR®) 1209; dicloreto de paraquate (Gramoxone®) 600; glifosato (Roundup Transorb®) 2592 g i.a. ha-1 classificados como levemente nocivos. Os fungicidas tiofanato-metílico (Cercobin 500 SC®) 400; flutriafol 60 + tiofanato-metílico 300 (Celeiro®); carbendazin (Derosal 500SC®) 250; tebuconazole (Folicur EC®) 150; flutriafol (Impact®) 125; tebuconazole 120 + trifloxistrobina 60 (Nativo®); epoxiconazole 30 + piraclostrobina 79,8 (Opera®); epoxiconazole (Opus SC®) 12,5; azoxistrobina (Priori®) 50; azoxistrobina 60 + ciproconazole 24 (Priori Xtra®) g i.a. ha-1 foram classificados como inócuos a T. pretiosum na fase de desenvolvimento avaliada (pupa). Dentre os produtos avaliados, aqueles classificados como inócuos devem ser priorizados no manejo integrado de pragas (MIP) por compatibilizar o uso do controle químico sem prejudicar o controle biológico. Do mesmo modo, os produtos classificados como moderadamente nocivos devem ser evitados sempre que possível ou substituídos por outro de menor impacto

    Underground Neutrino Detectors for Particle and Astroparticle Science: the Giant Liquid Argon Charge Imaging ExpeRiment (GLACIER)

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    The current focus of the CERN program is the Large Hadron Collider (LHC), however, CERN is engaged in long baseline neutrino physics with the CNGS project and supports T2K as recognized CERN RE13, and for good reasons: a number of observed phenomena in high-energy physics and cosmology lack their resolution within the Standard Model of particle physics; these puzzles include the origin of neutrino masses, CP-violation in the leptonic sector, and baryon asymmetry of the Universe. They will only partially be addressed at LHC. A positive measurement of sin22θ13>0.01\sin^22\theta_{13}>0.01 would certainly give a tremendous boost to neutrino physics by opening the possibility to study CP violation in the lepton sector and the determination of the neutrino mass hierarchy with upgraded conventional super-beams. These experiments (so called ``Phase II'') require, in addition to an upgraded beam power, next generation very massive neutrino detectors with excellent energy resolution and high detection efficiency in a wide neutrino energy range, to cover 1st and 2nd oscillation maxima, and excellent particle identification and π0\pi^0 background suppression. Two generations of large water Cherenkov detectors at Kamioka (Kamiokande and Super-Kamiokande) have been extremely successful. And there are good reasons to consider a third generation water Cherenkov detector with an order of magnitude larger mass than Super-Kamiokande for both non-accelerator (proton decay, supernovae, ...) and accelerator-based physics. On the other hand, a very massive underground liquid Argon detector of about 100 kton could represent a credible alternative for the precision measurements of ``Phase II'' and aim at significantly new results in neutrino astroparticle and non-accelerator-based particle physics (e.g. proton decay).Comment: 31 pages, 14 figure

    Poisson-Jacobi reduction of homogeneous tensors

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    The notion of homogeneous tensors is discussed. We show that there is a one-to-one correspondence between multivector fields on a manifold MM, homogeneous with respect to a vector field Δ\Delta on MM, and first-order polydifferential operators on a closed submanifold NN of codimension 1 such that Δ\Delta is transversal to NN. This correspondence relates the Schouten-Nijenhuis bracket of multivector fields on MM to the Schouten-Jacobi bracket of first-order polydifferential operators on NN and generalizes the Poissonization of Jacobi manifolds. Actually, it can be viewed as a super-Poissonization. This procedure of passing from a homogeneous multivector field to a first-order polydifferential operator can be also understood as a sort of reduction; in the standard case -- a half of a Poisson reduction. A dual version of the above correspondence yields in particular the correspondence between Δ\Delta-homogeneous symplectic structures on MM and contact structures on NN.Comment: 19 pages, minor corrections, final version to appear in J. Phys. A: Math. Ge

    Nernst branes from special geometry

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    We construct new black brane solutions in U(1)U(1) gauged N=2{\cal N}=2 supergravity with a general cubic prepotential, which have entropy density sT1/3s\sim T^{1/3} as T0T \rightarrow 0 and thus satisfy the Nernst Law. By using the real formulation of special geometry, we are able to obtain analytical solutions in closed form as functions of two parameters, the temperature TT and the chemical potential μ\mu. Our solutions interpolate between hyperscaling violating Lifshitz geometries with (z,θ)=(0,2)(z,\theta)=(0,2) at the horizon and (z,θ)=(1,1)(z,\theta)=(1,-1) at infinity. In the zero temperature limit, where the entropy density goes to zero, we recover the extremal Nernst branes of Barisch et al, and the parameters of the near horizon geometry change to (z,θ)=(3,1)(z,\theta)=(3,1).Comment: 37 pages. v2: numerical pre-factors of scalar fields q_A corrected in Section 3. No changes to conclusions. References adde

    Magnetic moment of Fe3O4 films with thicknesses near the unit-cell size

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    CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPEMIG - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAISFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORWe perform a systematic study on the evolution of the magnetic spin moment (ms) of epitaxial [100]- and [111]-magnetite films of increasing thickness. The ultrathin films are characterized by low-energy electron diffraction, x-ray absorption spectroscopy, and x-ray magnetic circular dichroism (XMCD). By employing sum rules on the XMCD spectra we obtain ms=3.6 μB/f.u. for samples of around 35 Å. This is considered a bulk value and has been reported only for films more than 10 times thicker. Moreover, we show that even 10-Å-thick magnetite already presents a significant magnetic moment. For both grown directions the moment increases similarly with the thickness. The ferromagnetic behavior for each iron ion site (Feocta2+, Feocta3+, Fetetra3+) of Fe3O4 is measured by monitoring XMCD peaks. The deduced hysteresis curves (per ion, per site) exhibit a coercive field of 300 Oe. Our results show that both the ferrimagnetic order and the bulk moment value are preserved at room temperature around the thickness of 2 unit cells.We perform a systematic study on the evolution of the magnetic spin moment (ms) of epitaxial [100]- and [111]-magnetite films of increasing thickness. The ultrathin films are characterized by low-energy electron diffraction, x-ray absorption spectroscopy, and x-ray magnetic circular dichroism (XMCD). By employing sum rules on the XMCD spectra we obtain ms=3.6 μB/f.u. for samples of around 35 Å. This is considered a bulk value and has been reported only for films more than 10 times thicker. Moreover, we show that even 10-Å-thick magnetite already presents a significant magnetic moment. For both grown directions the moment increases similarly with the thickness. The ferromagnetic behavior for each iron ion site (Feocta2+, Feocta3+, Fetetra3+) of Fe3O4 is measured by monitoring XMCD peaks. The deduced hysteresis curves (per ion, per site) exhibit a coercive field of 300 Oe. Our results show that both the ferrimagnetic order and the bulk moment value are preserved at room temperature around the thickness of 2 unit cells.We perform a systematic study on the evolution of the magnetic spin moment (ms) of epitaxial [100]- and [111]-magnetite films of increasing thickness. The ultrathin films are characterized by low-energy electron diffraction, x-ray absorption spectroscopy, and x-ray magnetic circular dichroism (XMCD). By employing sum rules on the XMCD spectra we obtain ms=3.6 μB/f.u. for samples of around 35 Å. This is considered a bulk value and has been reported only for films more than 10 times thicker. Moreover, we show that even 10-Å-thick magnetite already presents a significant magnetic moment. For both grown directions the moment increases similarly with the thickness. The ferromagnetic behavior for each iron ion site (Feocta2+, Feocta3+, Fetetra3+) of Fe3O4 is measured by monitoring XMCD peaks. The deduced hysteresis curves (per ion, per site) exhibit a coercive field of 300 Oe. Our results show that both the ferrimagnetic order and the bulk moment value are preserved at room temperature around the thickness of 2 unit cells.901316CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPEMIG - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAISFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPEMIG - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAISFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORSem informaçãoSem informaçãoSem informaçãoSem informaçãoOrna, J., Algarabel, P.A., Morellón, L., Pardo, J.A., De Teresa, J.M., López Antón, R., Bartolomé, F., Wildes, A., (2010) Phys. Rev. B, 81, p. 144420. , PRBMDO 1098-0121Hari Babu, V., Govind, R.K., Schindler, K.-M., Welke, M., Denecke, R., (2013) J. Appl. Phys., 114, p. 113901. , JAPIAU 0021-8979Moussy, J.-B., Gota, S., Bataille, A., Guittet, M.-J., Gautier-Soyer, M., Delille, F., Dieny, B., Snoeck, E., (2004) Phys. Rev. B, 70, p. 174448. , PRBMDO 1098-0121Morrall, P., Schedin, F., Langridge, S., Bland, J., Thomas, M.F., Thornton, G., (2003) J. Appl. Phys., 93, p. 7960. , JAPIAU 0021-8979Liu, W.Q., Xu, Y.B., Wong, P.K.J., Maltby, N.J., Li, S.P., Wang, X.F., Du, J., Zhang, R., (2014) Appl. Phys. Lett., 104, p. 142407. , APPLAB 0003-6951Lu, Y.X., Claydon, J.S., Xu, Y.B., Schofield, D.M., Thompson, S.M., (2004) J. Appl. Phys., 95, p. 7228. , JAPIAU 0021-8979Eerenstein, W., Hibma, T., Celotto, S., (2004) Phys. Rev. B, 70, p. 184404. , PRBMDO 1098-0121Voogt, F.C., Palstra, T.T.M., Niesen, L., Rogojanu, O.C., James, M.A., Hibma, T., (1998) Phys. Rev. B, 57, p. R8107. , PRBMDO 0163-1829Monti, M., Santos, B., Mascaraque, A., Rodríguez De La Fuente, O., Niño, M.A., Mentes, T.O., Locatelli, A., De La Figuera, J., (2012) Phys. Rev. B, 85, p. 020404. , PRBMDO 1098-0121Lu, Y.X., Claydon, J.S., Xu, Y.B., Thompson, S.M., Wilson, K., Van Der Laan, G., (2004) Phys. Rev. B, 70, p. 233304. , PRBMDO 1098-0121Lu, Y.X., Claydon, J.S., Ahmad, E., Xu, Y.B., Ali, M., Hickey, B.J., Thompson, S.M., Wilson, K., (2005) J. Appl. Phys., 97, p. 10C313Schedin, F., Hewitt, L., Morrall, P., Petrov, V.N., Thornton, G., Case, S., Thomas, M.F., Uzdin, V.M., (1998) Phys. Rev. B, 58, p. R11861. , PRBMDO 0163-1829Wong, P.K.J., Zhang, W., Cui, X.G., Xu, Y.B., Wu, J., Tao, Z.K., Li, X., Van Der Laan, G., (2010) Phys. Rev. B, 81, p. 035419. , PRBMDO 1098-0121Goering, E., Gold, S., Lafkioti, M., Schütz, G., (2006) Europhys. Lett., 73, p. 97. , EULEEJ 0295-5075Chen, C.T., Idzerda, Y.U., Lin, H.-J., Smith, N.V., Meigs, G., Chaban, E., Ho, G.H., Sette, F., (1995) Phys. Rev. Lett., 75, p. 152. , PRLTAO 0031-9007Goering, E.J., Lafkioti, M., Gold, S., Schuetz, G., (2007) J. Magn. Magn. Mater., 310, p. e249. , JMMMDC 0304-8853Figueiredo, J.J.S., Basilio, R., Landers, R., Garcia, F., De Siervo, A., (2009) J. Synch. Rad., 16, p. 346. , JSYRES 0909-0495Kallmayer, M., Hild, K., Elmers, H.J., Arora, S.K., Wu, H.-C., Sofin, R.G.S., Shvets, I.V., (2008) J. Appl. Phys., 103, p. 07D715. , JAPIAU 0021-8979Huang, D.J., Chang, C.F., Jeng, H.-T., Guo, G.Y., Lin, H.-J., Wu, W.B., Ku, H.C., Chen, C.T., (2004) Phys. Rev. Lett., 93, p. 077204. , PRLTAO 0031-9007Abreu, G.J.P., Paniago, R., Pfannes, H.-D., (2014) J. Magn. Magn. Mater., 349, p. 235. , JMMMDC 0304-8853Bruns, D., Lindemann, S.R., Kuepper, K., Schemme, T., Wollschläger, J., (2013) Appl. Phys. Lett., 103, p. 052401. , APPLAB 0003-6951Fonin, M., Pentcheva, R., Dedkov, Y.S., Sperlich, M., Vyalikh, D.V., Scheffler, M., Rüdiger, U., Güntherodt, G., (2005) Phys. Rev. B, 72, p. 104436. , PRBMDO 1098-0121Ritter, M., Over, H., Weiss, W., (1997) Surf. Sci., 371, p. 245. , SUSCAS 0039-6028Ritter, M., Ranke, W., Weiss, W., (1998) Phys. Rev. B, 57, p. 7240. , PRBMDO 0163-1829Weiss, W., Ritter, M., (1999) Phys. Rev. B, 59, p. 5201. , PRBMDO 0163-1829The authors thank CNPq, FAPEMIG, FAPESP, and CAPES, Brazilian research agencies, for financial support and the Laboratorio Nacional de Luz Sincrotron for beam time (SGM-10986 and SGM-12716)

    A Phase Transition between Small and Large Field Models of Inflation

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    We show that models of inflection point inflation exhibit a phase transition from a region in parameter space where they are of large field type to a region where they are of small field type. The phase transition is between a universal behavior, with respect to the initial condition, at the large field region and non-universal behavior at the small field region. The order parameter is the number of e-foldings. We find integer critical exponents at the transition between the two phases.Comment: 21 pages, 8 figure

    Corner contributions to holographic entanglement entropy

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    The entanglement entropy of three-dimensional conformal field theories contains a universal contribution coming from corners in the entangling surface. We study these contributions in a holographic framework and, in particular, we consider the effects of higher curvature interactions in the bulk gravity theory. We find that for all of our holographic models, the corner contribution is only modified by an overall factor but the functional dependence on the opening angle is not modified by the new gravitational interactions. We also compare the dependence of the corner term on the new gravitational couplings to that for a number of other physical quantities, and we show that the ratio of the corner contribution over the central charge appearing in the two-point function of the stress tensor is a universal function for all of the holographic theories studied here. Comparing this holographic result to the analogous functions for free CFT's, we find fairly good agreement across the full range of the opening angle. However, there is a precise match in the limit where the entangling surface becomes smooth, i.e., the angle approaches π\pi, and we conjecture the corresponding ratio is a universal constant for all three-dimensional conformal field theories. In this paper, we expand on the holographic calculations in our previous letter arXiv:1505.04804, where this conjecture was first introduced.Comment: 62 pages, 6 figures, 1 table; v2: minor modifications to match published version, typos fixe

    Human Fallopian Tube Mesenchymal Stromal Cells Enhance Bone Regeneration in a Xenotransplanted Model

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    We have recently reported that human fallopian tubes, which are discarded during surgical procedures of women submitted to sterilization or hysterectomies, are a rich source of human fallopian tube mesenchymal stromal cells (htMSCs). It has been previously shown that human mesenchymal stromal cells may be useful in enhancing the speed of bone regeneration. This prompted us to investigate whether htMSCs might be useful for the treatment of osteoporosis or other bone diseases, since they present a pronounced capacity for osteogenic differentiation in vitro. Based on this prior knowledge, our aim was to evaluate, in vivo, the osteogenic capacity of htMSCs to regenerate bone through an already described xenotransplantation model: nonimmunosuppressed (NIS) rats with cranial defects. htMSCs were obtained from five 30–50 years old healthy women and characterized by flow cytometry and for their multipotenciality in vitro capacity (osteogenic, chondrogenic and adipogenic differentiations). Two symmetric full-thickness cranial defects on each parietal region of seven NIS rats were performed. The left side (LS) of six animals was covered with CellCeram (Scaffdex)—a bioabsorbable ceramic composite scaffold that contains 60% hydroxyapatite and 40% β-tricalciumphosphate—only, and the right side (RS) with the CellCeram and htMSCs (106 cells/scaffold). The animals were euthanized at 30, 60 and 90 days postoperatively and cranial tissue samples were taken for histological analysis. After 90 days we observed neobone formation in both sides. However, in animals euthanized 30 and 60 days after the procedure, a mature bone was observed only on the side with htMSCs. PCR and immunofluorescence analysis confirmed the presence of human DNA and thus that human cells were not rejected, which further supports the imunomodulatory property of htMSCs. In conclusion, htMSCs can be used successfully to enhance bone regeneration in vivo, opening a new field for future treatments of osteoporosis and bone reconstruction

    G-band Spectral Synthesis in Solar Magnetic Concentrations

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    Narrow band imaging in the G-band is commonly used to trace the small magnetic field concentrations of the Sun, although the mechanism that makes them bright has remained unclear. We carry out LTE syntheses of the G-band in an assorted set of semi-empirical model magnetic concentrations. The syntheses include all CH lines as well as the main atomic lines within the band-pass. The model atmospheres produce bright G-band spectra having many properties in common with the observed G-band bright points. In particular, the contrast referred to the quiet Sun is about twice the contrast in continuum wavelengths. The agreement with observations does not depend on the specificities of the model atmosphere, rather it holds from single fluxtubes to MIcro-Structured Magnetic Atmospheres. However, the agreement requires that the real G-band bright points are not spatially resolved, even in the best observations. Since the predicted G-band intensities exceed by far the observed values, we foresee a notable increase of contrast of the G-band images upon improvement of the angular resolution. According to the LTE modeling, the G-band spectrum emerges from the deep photosphere that produces the continuum. Our syntheses also predict solar magnetic concentrations showing up in continuum images but not in the G-band . Finally, we have examined the importance of the CH photo-dissociation in setting the amount of G-band absorption. It turns out to play a minor role.Comment: To appear in ApJ, 554 n2 Jun 20, 33 pages and 9 figure
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