Competition between local potentials and attractive particle-particle interactions in superlattices

Naturally occuring or man-made systems displaying periodic spatial modulations of their properties on a nanoscale constitute superlattices. Such modulated structures are important both as prototypes of simple nanotechnological devices and as particular examples of emerging spatial inhomogeneity in interacting many-electron systems. Here we investigate the effect different types of modulation of the system parameters have on the ground-state energy and the charge-density distribution of the system. The superlattices are described by the inhomogeneous attractive Hubbard model, and the calculations are performed by density-functional and density-matrix renormalization group techniques. We find that modulations in local electric potentials are much more effective in shaping the system's properties than modulations in the attractive on-site interaction. This is the same conclusions we previously (Phys. Rev. B 71, 125130) obtained for repulsive interactions, suggesting that it is not an artifact of a specific state, but a general property of modulated structures.Comment: 8 pages, 2 figure

Bronchoscopy For Foreign Body Removal: Where Is The Delay? [broncoscopia Para Remoção De Corpo Estranho: Onde Está O Atraso?]

This was a retrospective analysis of the medical charts of 145 patients treated at the Bronchoscopy and Thoracic Surgery Clinic of the Hospital das Clínicas da Universidade Estadual de Campinas (HC-Unicamp, State University of Campinas Hospital das Clínicas) over a period of 10 years. There was a significant difference related to the site of first medical visit (Unicamp-HC versus other institutions) in terms of the time elapsed between the suspicion of bronchial aspiration and the actual respiratory endoscopic examination. However, no significant difference was found in the rate of positive results. The low number of referral centers that provide emergency respiratory endoscopy can negatively influence the treatment of patients under suspicion of bronchial aspiration, jeopardizing the overall recovery in the mid- and long-term.3411956958Zerella, J.T., Dimler, M., McGill, L.C., Pippus, K.J., Foreign body aspiration in children: Value of radiography and complications of bronchoscopy (1998) J Ped Surg, 33 (11), pp. 1651-1654Fraga, A.M., Reis, M.C., Zambon, M.P., Toro, I.C., Ribeiro, J.D., Baracat, E.C., Foreign body aspiration in children: Clinical aspects, radiological aspects and bronchoscopic treatment (2008) J Bras Pneumol, 34 (2), pp. 74-82Swanson, K.L., Prakash, U.B., Midthun, D.E., Edell, E.S., Utz, J.P., McDougall, J.C., Flexible bronchoscopic management of airway foreign bodies in children (2002) Chest, 121 (5), pp. 1695-1700Pritt, B., Harmon, M., Schwartz, M., Cooper, K., A tale of three aspirations: Foreign bodies in the airway (2003) J Clin Pathol, 56 (10), pp. 791-794Cataneo, A.J., Reibscheid, S.M., Ruiz Júnior, R.L., Ferrari, G.F., Foreign body in the tracheobronchial tree (1997) Clin Pediatr (Phila), 36 (12), pp. 701-706Applegate, K.E., Dardinger, J.T., Lieber, M.L., Herts, B.R., Davros, W.J., Obuchowski, N.A., Spiral CT scanning technique in the detection of aspiration of LEGO foreign bodies (2001) Pediatr Radiol, 31 (12), pp. 836-840Lima, J.A., Fischer, G.B., Felicetti, J.C., Flores, J.A., Penna, C.N., Ludwig, E., Aspiração de corpo estranho na árvore traqueobrônquica em crianças: Avaliação de seqüelas através de exame cintilográfico. (2000) J Pneumol, 26 (1), pp. 20-24Cassol, V., Pereira, A.M., Zorzela, L.M., Becker, M.M., Barreto, S.S., Corpo estranho na via aérea de crianças. (2003) J Pneumol, 29 (3), pp. 139-144Fraga, J.C., Nogueira, A., Palombini, B.C., Corpo estranho em via aérea de criança. (1994) J Pneumol, 20 (3), pp. 107-111Piva, J., Giugno, K., Maia, T., Mascarenhas, T., Nogueira, A., Kalil, L., Aspiração de corpo estranho: Revisão de 19 casos. (1989) J Pediat, 65 (10), pp. 399-403Inglis Jr, A.F., Wagner, D.V., Lower complication rates associated with bronchial foreign bodies over the last 20 years (1992) Ann Otol Rhinol Laryngol, 101 (1), pp. 61-66Davies, H., Gordon, I., Matthew, D.J., Helms, P., Kenney, I.J., Lutkin, J.E., Long term follow up after inhalation of foreign bodies (1990) Arch Dis Child, 65 (6), pp. 619-621Black, R.E., Choi, K.J., Syme, W.C., Johnson, D.G., Matlak, M.E., Bronchoscopic removal of aspirated foreign bodies in children (1984) Am J Surg, 148 (6), pp. 778-78

Conformal symmetry and deflationary gas universe

We describe the ``deflationary'' evolution from an initial de Sitter phase to a subsequent Friedmann-Lema\^{\i}tre-Robertson-Walker (FLRW) period as a specific non-equilibrium configuration of a self-interacting gas. The transition dynamics corresponds to a conformal, timelike symmetry of an ``optical'' metric, characterized by a refraction index of the cosmic medium which continously decreases from a very large initial value to unity in the FLRW phase.Comment: 10 pages, to appear in "Exact Solutions and Scalar Fields in Gravity: Recent Developments", ed. by A. Macias, J. Cervantes-Cota, and C. L\"ammerzahl, Kluwer Academic Publishers 200

Development of β-TCP-Ti6Al4V structures: Driving cellular response by modulating physical and chemical properties

Acknowledgments This work was supported by FCT (Fundação para a Ciência e Tecnologia) through the grants SFRH/BD/140191/2018; SFRH/BPD/112111/2015, SFRH/BD/128657/2017, SFRH/BD/141056/2018; SFRH/BPD/97701/2013, PD/BDE/127836/2016, and the projects PTDC/EMS-TEC/5422/2014_ADAPTPROSTHESIS and NORTE-01- 0145-FEDER-000018-HAMaBICo. Additionally, this work was supported by FCT with the reference project UID/EEA/04436/2013, by FEDER funds through the COMPETE 2020 – Programa Operacional Competitividade e Internacionalização (POCI) with the reference project POCI-01-0145-FEDER-006941.Load-bearing implants success is strongly dependent on several physical and chemical properties that are known to drive cellular response. In this work, multi-material β-TCP-Ti6Al4V cellular structures were designed to combine Ti6Al4V mechanical properties and β-Tricalcium Phosphate bioactivity, in order to promote bone ingrowth as the bioactive material is being absorbed and replaced by newly formed bone. In this sense, the produced structures were characterized regarding roughness, wettability, β-TCP quantity and quality inside the structures after fabrication and the pH measured during cell culture (as consequence of β-TCP dissolution) and those aspects were correlated with cellular viability, distribution, morphology and proliferation. These structures displayed a hydrophilic behavior and results showed that the addition of β-TCP to these cellular structures led to an alkalization of the medium, aspect that significantly influences the cellular response. Higher impregnation ratios were found more adequate for lowering the media pH and toxicity, and thus enhance cell adhesion and proliferation.info:eu-repo/semantics/publishedVersio

45S5 BAG-Ti6Al4V structures: The influence of the design on some of the physical and chemical interactions that drive cellular response

This work was supported by FCT (Fundação para a Ciência e Tecnologia) through the grants SFRH/BPD/112111/2015, SFRH/BD/128657/2017, PD/BDE/127836/2016, SFRH/BPD/97701/2013, SFRH/ BD/141056/2018, SFRH/BD/140191/2018 and the projects PTDC/EMSTEC/5422/2014 and NORTE-01-0145-FEDER-000018-HAMaBICo. Additionally, this work was supported by FCT with the reference project UID/EEA/04436/2013, by FEDER funds through the COMPETE 2020 – Programa Operacional Competitividade e Internacionalização (POCI) with the reference project POCI-01-0145-FEDER-006941.Multi-material Ti6Al4V cellular structures impregnated with 45S5 bioactive glass were designed and produced using Selective LaserMelting (SLM), an additive manufacturing technique, combinedwith Press and Sintering focusing on load bearing components like hip implants. These structures were designed to combine Ti6Al4V mechanical properties and promote bone ingrowth into the structure as the bioactive material (45S5) is being absorbed and replaced by newly formed bone. The influence of these structures design on some of the physical and chemical aspects that drive cellular response was assessed. Roughness, wettability, bioactive glass quantity and quality on the structures after processing and the pH measured during cell culture (as a consequence of bioactive glass dissolution) were evaluated and correlated with cellular viability, cellular distribution, morphology and proliferation on the surface and inside the structures.info:eu-repo/semantics/publishedVersio

Self-Calibration of Cluster Dark Energy Studies: Counts in Cells

Cluster number counts can constrain the properties of dark energy if and only if the evolution in the relationship between observable quantities and the cluster mass can be calibrated. Next generation surveys with ~10000 clusters will have sufficient statistics to enable some degree of self-calibration. The excess variance of counts due to the clustering of clusters provides such an opportunity and can be measured from the survey without additional observational cost. It can minimize the degradation in dark energy constraints due to an unknown power law evolution in the mass-observable relation improving constraints on the dark energy equation of state by a factor of 2 or more to sigma(w)=0.06 for a deep 4000 deg2 survey.Comment: 4 pages 2 figures submitted to PR

eta-prime photoproduction on the proton for photon energies from 1.527 to 2.227 GeV

Differential cross sections for the reaction gamma p -> eta-prime p have been measured with the CLAS spectrometer and a tagged photon beam with energies from 1.527 to 2.227 GeV. The results reported here possess much greater accuracy than previous measurements. Analyses of these data indicate for the first time the coupling of the etaprime N channel to both the S_11(1535) and P_11(1710) resonances, known to couple strongly to the eta N channel in photoproduction on the proton, and the importance of j=3/2 resonances in the process.Comment: 6 pages, 3 figure

Measurement of the Deuteron Structure Function F2 in the Resonance Region and Evaluation of Its Moments

Inclusive electron scattering off the deuteron has been measured to extract the deuteron structure function F2 with the CEBAF Large Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility. The measurement covers the entire resonance region from the quasi-elastic peak up to the invariant mass of the final-state hadronic system W~2.7 GeV with four-momentum transfers Q2 from 0.4 to 6 (GeV/c)^2. These data are complementary to previous measurements of the proton structure function F2 and cover a similar two-dimensional region of Q2 and Bjorken variable x. Determination of the deuteron F2 over a large x interval including the quasi-elastic peak as a function of Q2, together with the other world data, permit a direct evaluation of the structure function moments for the first time. By fitting the Q2 evolution of these moments with an OPE-based twist expansion we have obtained a separation of the leading twist and higher twist terms. The observed Q2 behaviour of the higher twist contribution suggests a partial cancellation of different higher twists entering into the expansion with opposite signs. This cancellation, found also in the proton moments, is a manifestation of the "duality" phenomenon in the F2 structure function