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3. Vortex reconnections and rebounds in trapped atomic Bose--Einstein condensates

Author

Serafini, Simone, Galantucci, Luca, Iseni, Elena, Bienaimé, Tom, Bisset, Russell N., Barenghi, Carlo F., Dalfovo, Franco, Lamporesi, Giacomo, and Ferrari, Gabriele

Subjects
Condensed Matter - Quantum Gases
Abstract

Reconnections and interactions of filamentary coherent structures play a fundamental role in the dynamics of fluids, plasmas and nematic liquid crystals. In fluids, vortex reconnections redistribute energy and helicity among the length scales and induce fine-scale turbulent mixing. Unlike ordinary fluids where vorticity is a continuous field, in quantum fluids vorticity is concentrated into discrete (quantized) vortex lines turning vortex reconnections into isolated events, making it conceptually easier to study. Here we report experimental and numerical observations of three-dimensional quantum vortex interactions in a cigar-shaped atomic Bose-Einstein Condensate (BEC). In addition to standard reconnections, already numerically and experimentally observed in homogeneous systems away from boundaries, we show that double reconnections, rebounds and ejections can also occur as a consequence of the non-homogeneous, confined nature of the system., Comment: 10 pages, 4 figures

Published
2016
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4. Spin-Dipole Oscillation and Polarizability of a Binary Bose-Einstein Condensate near the Miscible-Immiscible Phase Transition

Author

Bienaimé, Tom, Fava, Eleonora, Colzi, Giacomo, Mordini, Carmelo, Serafini, Simone, Qu, Chunlei, Stringari, Sandro, Lamporesi, Giacomo, and Ferrari, Gabriele

Subjects
Condensed Matter - Quantum Gases
Abstract

We report on the measurement of the spin-dipole (SD) polarizability and of the frequency of the SD oscillation of a two-component Bose-Einstein condensate of sodium atoms occupying the $|3^2S_{1/2}, F=1, m_F=\pm1\rangle$ hyperfine states. This binary spin-mixture presents the important properties of being, at the same time, fully miscible and rid of the limit set by buoyancy. It is also characterized by a huge enhancement of the SD polarizability and by the consequent softening of the frequency of the SD oscillation, due to the vicinity to the transition to the immiscible phase. The experimental data are successfully compared with the predictions of theory., Comment: 6 pages, 4 figures

Published
2016
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5. Creation and counting of defects in a temperature quenched Bose-Einstein Condensate

Author

Donadello, Simone, Serafini, Simone, Bienaimé, Tom, Dalfovo, Franco, Lamporesi, Giacomo, and Ferrari, Gabriele

Subjects
Condensed Matter - Quantum Gases
Abstract

We study the spontaneous formation of defects in the order parameter of a trapped ultracold bosonic gas while crossing the critical temperature for Bose-Einstein Condensation (BEC) at different rates. The system has the shape of an elongated ellipsoid, whose transverse width can be varied to explore dimensionality effects. For slow enough temperature quenches we find a power-law scaling of the average defect number with the quench rate, as predicted by the Kibble-Zurek mechanism. A breakdown of such a scaling is found for fast quenches, leading to a saturation of the average defect number. We suggest an explanation for this saturation in terms of the mutual interactions among defects., Comment: 9 pages, 10 figures

Published
2016
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6. Sub-Doppler cooling of sodium atoms in gray molasses

Author

Colzi, Giacomo, Durastante, Gianmaria, Fava, Eleonora, Serafini, Simone, Lamporesi, Giacomo, and Ferrari, Gabriele

Subjects
Condensed Matter - Quantum Gases, Physics - Atomic Physics
Abstract

We report on the realization of sub-Doppler laser cooling of sodium atoms in gray molasses using the D1 optical transition ($3s\, ^2S_{1/2} \rightarrow 3p\, ^2P_{1/2}$) at 589.8 nm. The technique is applied to samples containing $3\times10^9$ atoms, previously cooled to 350 $\mu$K in a magneto-optical trap, and it leads to temperatures as low as 9 $\mu$K and phase-space densities in the range of $10^{-4}$. The capture efficiency of the gray molasses is larger than 2/3, and we observe no density-dependent heating for densities up to $10^{11}$ cm$^{-3}$., Comment: 6 pages, 4 figures

Published
2015
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8. Dynamics and interaction of vortex lines in an elongated Bose-Einstein condensate

Author

Serafini, Simone, Barbiero, Matteo, Debortoli, Michele, Donadello, Simone, Larcher, Fabrizio, Dalfovo, Franco, Lamporesi, Giacomo, and Ferrari, Gabriele

Subjects
Condensed Matter - Quantum Gases
Abstract

We study the real-time dynamics of vortex lines in a large elongated Bose-Einstein condensate (BEC) of sodium atoms using a stroboscopic technique. Vortices are spontaneously produced via the Kibble-Zurek mechanism in a quench across the BEC transition and then they slowly precess keeping their orientation perpendicular to the long axis of the trap as expected for solitonic vortices in a highly anisotropic condensate. Good agreement with theoretical predictions is found for the precession period as a function of the orbit amplitude and the number of condensed atoms. In configurations with two or more vortex lines, we see signatures of vortex-vortex interaction in the shape and visibility of the orbits. In addition, when more than two vortices are present, their decay is faster than the thermal decay observed for one or two vortices. The possible role of vortex reconnection processes is discussed., Comment: 4 pages, 4 figures

Published
2015
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9. Solitonic Vortices in Bose-Einstein Condensates

Author

Tylutki, Marek, Donadello, Simone, Serafini, Simone, Pitaevskii, Lev P., Dalfovo, Franco, Lamporesi, Giacomo, and Ferrari, Gabriele

Subjects
Condensed Matter - Quantum Gases
Abstract

We analyse, theoretically and experimentally, the nature of solitonic vortices (SV) in an elongated Bose-Einstein condensate. In the experiment, such defects are created via the Kibble-Zurek mechanism, when the temperature of a gas of sodium atoms is quenched across the BEC transition, and are imaged after a free expansion of the condensate. By using the Gross-Pitaevskii equation, we calculate the in-trap density and phase distributions characterizing a SV in the crossover from an elongate quasi-1D to a bulk 3D regime. The simulations show that the free expansion strongly amplifies the key features of a SV and produces a remarkable twist of the solitonic plane due to the quantized vorticity associated with the defect. Good agreement is found between simulations and experiments., Comment: 6 pages, 4 figures

Published
2014
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10. Observation of Solitonic Vortices in Bose-Einstein Condensates

Author

Donadello, Simone, Serafini, Simone, Tylutki, Marek, Pitaevskii, Lev P., Dalfovo, Franco, Lamporesi, Giacomo, and Ferrari, Gabriele

Subjects
Condensed Matter - Quantum Gases
Abstract

We observe solitonic vortices in an atomic Bose-Einstein condensate after free expansion. Clear signatures of the nature of such defects are the twisted planar density depletion around the vortex line, observed in absorption images, and the double dislocation in the interference pattern obtained through homodyne techniques. Both methods allow us to determine the sign of the quantized circulation. Experimental observations agree with numerical simulations. These solitonic vortices are the decay product of phase defects of the BEC order parameter spontaneously created after a rapid quench across the BEC transition in a cigar-shaped harmonic trap and are shown to have a very long lifetime., Comment: 7 pages, 7 figures

Published
2014
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11. Spontaneous creation of Kibble-Zurek solitons in a Bose-Einstein condensate

Author

Lamporesi, Giacomo, Donadello, Simone, Serafini, Simone, Dalfovo, Franco, and Ferrari, Gabriele

Subjects
Condensed Matter - Quantum Gases, Physics - Atomic Physics
Abstract

When a system crosses a second-order phase transition on a finite timescale, spontaneous symmetry breaking can cause the development of domains with independent order parameters, which then grow and approach each other creating boundary defects. This is known as Kibble-Zurek mechanism. Originally introduced in cosmology, it applies both to classical and quantum phase transitions, in a wide variety of physical systems. Here we report on the spontaneous creation of solitons in Bose-Einstein condensates via the Kibble-Zurek mechanism. We measure the power-law dependence of defects number with the quench time, and provide a check of the Kibble-Zurek scaling with the sonic horizon. These results provide a promising test bed for the determination of critical exponents in Bose-Einstein condensates., Comment: 7 pages, 4 figures

Published
2013
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12. Surgical oncological emergencies in octogenarian patients

Author

Friziero, Alberto, primary, Sperti, Cosimo, additional, Riccio, Federica, additional, Zuin, Irene Sole, additional, Vallese, Lorenzo, additional, Serafini, Simone, additional, Amico, Alessandra, additional, Valli, Valeria, additional, Da Re, Chiara, additional, Baldan, Nicola, additional, Valmasoni, Michele, additional, and Da Dalt, Gianfranco, additional

Published
2023
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21. The role of resection for melanoma metastases to the pancreas

Author

Guerra, Francesco, primary, Coletta, Diego, additional, Deutsch, Gary B., additional, Giuliani, Giuseppe, additional, Patriti, Alberto, additional, Fischer, Trevan D., additional, Coratti, Andrea, additional, Serafini, Simone, additional, Surjan, Rodrigo, additional, Milanetto, Anna C., additional, and Campra, Donata, additional

Published
2022
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22. Medullary Thyroid Carcinoma in a Patient with MEN 1 Syndrome. Case Report and Literature Review

Author

Friziero, Alberto, Da Dalt, Gianfranco, Piotto, Andrea, Serafini, Simone, Grego, Andrea, Galuppini, Francesca, Pennelli, Gianmaria, and Sperti, Cosimo

Subjects
multiple endocrine neoplasia type 2, endocrine system diseases, RET gene, thyroidectomy, thyroid cancer, MEN 1 gene, multiple endocrine neoplasia type 1, multiple endocrine neoplasia type 2, RET gene, thyroid cancer, thyroidectomy, Case Report, multiple endocrine neoplasia type 1, MEN 1 gene
Abstract

Medullary thyroid cancer (MTC) is typically associated with multiple endocrine neoplasia type 2 syndrome (MEN 2), but not with multiple endocrine neoplasia type 1 (MEN 1). We report a very rare case of MTC in a patient with MEN 1 syndrome. A 60-year-old Caucasian woman with sporadic MEN 1 syndrome was admitted in October 2018 for recurrent hyperparathyroidism unresponsive to medical therapy. Her medical history included the diagnosis of a non-functioning pancreatic neuroendocrine tumor (NF-pNET) of the head of the pancreas 1.5 cm in size in 2001, and subtotal parathyroidectomy for uncontrolled hyperparathyroidism due to bilateral parathyroid hyperplasia in the same year. This history prompted genetic studies, and MEN 1 syndrome was confirmed. Family screening was performed in first-degree relatives, with negative results. Other typical clinical manifestations of MEN 1 syndrome were ruled out. In November 2018, the patient underwent excision of the residual left inferior parathyroid, extended to include the left thyroid lobe, for recurrent uncontrolled hyperparathyroidism. The pathologist identified MTC and adenoma of the parathyroid gland. Genetic tests were performed to identify any RET mutation, with negative results. The patient underwent total thyroidectomy about 6 months later, and the subsequent histological report showed only focal reactive C-cell hyperplasia of the thyroid. A literature review identified only three previously published cases of MTC coexisting with MEN 1 syndrome. This association may have two etiological hypotheses: either a sporadic MTC arising in a patient with MEN 1 syndrome, or a rare case of medullary cancer linked to a MEN 1 gene mutation.

Published
2020

25. The Prognostic Value of Low Muscle Mass in Pancreatic Cancer Patients: A Systematic Review and Meta-Analysis

Author

Pierobon, Elisa Sefora, primary, Moletta, Lucia, additional, Zampieri, Sandra, additional, Sartori, Roberta, additional, Brazzale, Alessandra Rosalba, additional, Zanchettin, Gianpietro, additional, Serafini, Simone, additional, Capovilla, Giovanni, additional, Valmasoni, Michele, additional, Merigliano, Stefano, additional, and Sperti, Cosimo, additional

Published
2021
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28. Medullary Thyroid Carcinoma in a Patient with MEN 1 Syndrome. Case Report and Literature Review

Author

Friziero,Alberto, Da Dalt,Gianfranco, Piotto,Andrea, Serafini,Simone, Grego,Andrea, Galuppini,Francesca, Pennelli,Gianmaria, Sperti,Cosimo, Friziero,Alberto, Da Dalt,Gianfranco, Piotto,Andrea, Serafini,Simone, Grego,Andrea, Galuppini,Francesca, Pennelli,Gianmaria, and Sperti,Cosimo

Abstract

Alberto Friziero,1 Gianfranco Da Dalt,1 Andrea Piotto,1 Simone Serafini,1 Andrea Grego,1 Francesca Galuppini,2 Gianmaria Pennelli,3 Cosimo Sperti1 1Department of Surgery, Oncology and Gastroenterology-DISCOG, 3rd Surgical Clinic, University of Padua, Padua, Italy; 2Department of Woman’s and Children’s Health-SDB, University of Padua, Padua, Italy; 3Department of Medicine-DIMED, Pathology Unit, University of Padua, Padua, ItalyCorrespondence: Cosimo SpertiDepartment of Surgery, Oncology and Gastroenterology, 3 rd Surgical Clinic, University of Padua, via Giustiniani 2, Padova 35128, ItalyTel +39 0498218845Fax +39 0498218821Email csperti@libero.itAbstract: Medullary thyroid cancer (MTC) is typically associated with multiple endocrine neoplasia type 2 syndrome (MEN 2), but not with multiple endocrine neoplasia type 1 (MEN 1). We report a very rare case of MTC in a patient with MEN 1 syndrome. A 60-year-old Caucasian woman with sporadic MEN 1 syndrome was admitted in October 2018 for recurrent hyperparathyroidism unresponsive to medical therapy. Her medical history included the diagnosis of a non-functioning pancreatic neuroendocrine tumor (NF-pNET) of the head of the pancreas 1.5 cm in size in 2001, and subtotal parathyroidectomy for uncontrolled hyperparathyroidism due to bilateral parathyroid hyperplasia in the same year. This history prompted genetic studies, and MEN 1 syndrome was confirmed. Family screening was performed in first-degree relatives, with negative results. Other typical clinical manifestations of MEN 1 syndrome were ruled out. In November 2018, the patient underwent excision of the residual left inferior parathyroid, extended to include the left thyroid lobe, for recurrent uncontrolled hyperparathyroidism. The pathologist identified MTC and adenoma of the parathyroid gland. Genetic tests were performed to identify any RET mutation, with negative results. The patient underwent total thyroidectomy about 6 months later, and the subse

Published
2020

39. Dynamics of Vortices and their Interactions in Bose-Einstein Condensates

Author

Serafini, Simone and Ferrari, Gabriele

Subjects
Physics::Fluid Dynamics, Condensed Matter::Quantum Gases, FIS/01 FISICA SPERIMENTALE, Condensed Matter::Other, Condensed Matter::Superconductivity, FIS/03 FISICA DELLA MATERIA
Abstract

Vortex reconnections and interactions play a fundamental role in the dynamics of fluids and turbulent flows, both in the classical and quantum regime. Studying vortices in a clean system like ultracold gases can therefore help, as a bottom-up approach, to understand the physics in a wider context, including superfluid helium, polariton condensates, fluid dynamics and turbulence, neutron stars and cosmological models. So far vortex-vortex interaction was studied in Bose-Einstein condensates either in rotating systems with the observation of regular Abrikosov lattices or in flat condensates across the Berezinskii-Kosterlitz-Thouless transition. In both cases the geometrical constraints allowed to study just a planar interaction among aligned or anti-aligned vortices. The present study instead is carried out in an axisymmetric cigar-shaped Bose-Einstein condensate. Vortices in prolate structures are also known as solitonic vortices. This geometry is especially suitable for investigating vortex interactions. Indeed vortices are oriented perpendicularly to the condensate axis to minimize their length, hence energy, and, because of the cylindrical symmetry, the orientation of a vortex in the radial plane has no constraints. These facts permit interactions to occur with different incoming relative angles between the vortex lines and with different relative velocities. The strong confinement, acting along the radial axis, enhances also interesting effects due to the boundaries.

Published
2017

44. Liver resection for metastases from colorectal cancer in very elderly patients: New surgical horizons

Author

Nardo, Bruno, primary, Serafini, Simone, additional, Ruggiero, Michele, additional, Grande, Raffaele, additional, Fugetto, Francesco, additional, Zullo, Alessandra, additional, Novello, Matteo, additional, Rizzuto, Antonia, additional, Bonaiuto, Elisabetta, additional, Vaccarisi, Sebastiano, additional, Cavallari, Giuseppe, additional, Serra, Raffaele, additional, Cannistrà, Marco, additional, and Sacco, Rosario, additional

Published
2016
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48. One-lung ventilation to treat hepatic dome lesion - a further step towards minimally invasive surgery: a case report.

Author

D'Amico, Francesco, Serafini, Simone, Finotti, Michele, Di Bello, Marianna, Di Renzo, Chiara, and Cillo, Umberto

Subjects
*MINIMALLY invasive procedures, *ABDOMINAL surgery, *ACOUSTICAL materials, *HEPATOCELLULAR carcinoma
Abstract

Background: Although liver resection is still the best treatment for primary or metastatic hepatic lesions, a conventional surgical approach may be challenging in patients with a history of previous abdominal surgery. We present a case of a 58-year-old white man with paracaval, subdiaphragmatic, recurrent hepatocellular carcinoma; he had a history of multiple abdominal surgeries.Methods: In select patients, percutaneous ultrasound-guided thermal ablation is a valid non-surgical alternative due to its safety, efficacy, and good tolerability. Hepatic lesions located in the posterosuperior segments, however, can be difficult to reach via a percutaneous approach.Result: For these cases, one-lung left-sided ventilation may be particularly helpful in blocking the right hemidiaphragm and improving the acoustic window to the liver.Conclusion: We present a case of paracaval, subdiaphragmatic, recurrent hepatocellular carcinoma in which the tumor was only reachable after one-lung left-sided ventilation that was successfully treated by percutaneous ultrasound-guided microwave ablation. [ABSTRACT FROM AUTHOR]

Published
2019
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49. Public Transport-Based Crowdshipping for Sustainable City Logistics: Assessing Economic and Environmental Impacts.

Author

Gatta, Valerio, Marcucci, Edoardo, Nigro, Marialisa, Patella, Sergio Maria, and Serafini, Simone

Abstract

This paper aims at understanding and evaluating the environmental and economic impacts of a crowdshipping platform in urban areas. The investigation refers to the city of Rome and considers an environmental-friendly crowdshipping based on the use of the mass transit network of the city, where customers/crowdshippers pick-up/drop-off goods in automated parcel lockers located either inside the transit stations or in their surroundings. Crowdshippers are passengers that would use the transit network anyhow for other activities (e.g., home-to-work), thus avoiding additional trips. The study requires firstly, estimating the willingness to buy a crowdshipping service like the one proposed here, in order to quantify the potential demand. The estimation is realized adopting an extensive stated preference survey and discrete choice modeling. Then, several scenarios with different features of the service are proposed and evaluated up to 2025 in terms of both externalities (local and global pollutant emissions, noise emissions and accidents reductions) and revenues. The results are useful to understand and quantify the potential of this strategy for last mile B2C deliveries. Moreover, it provides local policy-makers and freight companies with a good knowledge base for the future development of a platform for public transport-based crowdshipping and for estimating the likely impact the system could have both from an economic and environmental point of view. [ABSTRACT FROM AUTHOR]

Published
2019
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50. Sustainable urban freight transport adopting public transport-based crowdshipping for B2C deliveries

Author

Edoardo Marcucci, Marialisa Nigro, Simone Serafini, Valerio Gatta, Gatta, Valerio, Marcucci, Edoardo, Nigro, Marialisa, and Serafini, Simone

Subjects
Discrete choice models, 0211 other engineering and technologies, Transportation, Context (language use), 02 engineering and technology, 0502 economics and business, On demand economy, Transit (satellite), Service (business), 050210 logistics & transportation, Discrete choice, business.industry, Mechanical Engineering, 05 social sciences, lcsh:TA1001-1280, Urban freight transport, 021107 urban & regional planning, Environmental economics, lcsh:HE1-9990, Preference, Discrete choice model, City logistic, Knowledge base, Public transport, Automotive Engineering, TRIPS architecture, Stated preference, Crowdshipping, lcsh:Transportation engineering, lcsh:Transportation and communications, City logistics, business
Abstract

Cities crave innovative logistics solutions dealing with the requirements of the ‘on demand economy’. The paper estimates the willingness to act as a crowdshipper (supply) and to buy a crowdshipping service (demand) to get goods delivered/picked-up in the last mile B2C e-commerce situation. Specifically, it innovates by considering an environmental-friendly crowdshipping based on the use of the mass transit network of the city where parcels customers/crowdshippers pick-up/drop-off goods in automated parcel lockers located either inside the transit stations or in the surroundings. This issue is very important since “standard” crowdshipping is usually not able to reduce congestion and polluting emissions due to the dedicated trips performed using private motorized vehicles. The paper rests on an extensive stated preference survey. The hypothetical scenarios used to acquire both demand (customers’) and supply (crowdshippers’) preferences make use of the most relevant attributes emerging from a preliminary investigation performed in the study context. The investigation is performed in the city of Rome and the metro is the transit system considered. The results are useful in understanding and quantifying the potential of this freight transport strategy for e-commerce in an urban context and in providing local policy makers with a good knowledge base for its future development.

Published
2019

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