12,246 results on '"Marchetti P"'
Search Results
152. A New Level II Oncoplastic Technique for Inferior Pole Defects: The Three-Petal Glandular Reconstruction (3-PR)
- Author
-
De Lorenzi, Francesca, Borelli, Francesco, Alessandri-Bonetti, Mario, Marchetti, Alberto, Dias, Leonardo Pires Novais, Invento, Alessandra, Rossi, Elisabetta Maria Cristina, Loschi, Pietro, and Veronesi, Paolo
- Published
- 2024
- Full Text
- View/download PDF
153. Long-Term Urban and Population Trends in the Southern Mesopotamian Floodplains
- Author
-
Marchetti, Nicolò, Bortolini, Eugenio, Menghi Sartorio, Jessica Cristina, Orrù, Valentina, and Zaina, Federico
- Published
- 2024
- Full Text
- View/download PDF
154. A network analysis-based framework to understand the representation dynamics of graph neural networks
- Author
-
Bonifazi, Gianluca, Cauteruccio, Francesco, Corradini, Enrico, Marchetti, Michele, Ursino, Domenico, and Virgili, Luca
- Published
- 2024
- Full Text
- View/download PDF
155. Paleolimnological evidence of the Inverted Trophic Cascade Hypothesis in a Neotropical lake
- Author
-
Maroneze, Daniel Marchetti, Menendez, Rosa Maria, Ferreira, Daniela Rabello, Pujoni, Diego Guimarães Florencio, de Lima Ferreira, Paulo Alves, Figueira, Rubens Cesar Lopes, and Maia-Barbosa, Paulina Maria
- Published
- 2024
- Full Text
- View/download PDF
156. A Systematization of Cybersecurity Regulations, Standards and Guidelines for the Healthcare Sector
- Author
-
Carello, Maria Patrizia, Spaccamela, Alberto Marchetti, Querzoni, Leonardo, and Angelini, Marco
- Subjects
Computer Science - Cryptography and Security ,Computer Science - Computers and Society ,K.6.5 ,K.5 - Abstract
The growing adoption of IT solutions in the healthcare sector is leading to a steady increase in the number of cybersecurity incidents. As a result, organizations worldwide have introduced regulations, standards, and best practices to address cybersecurity and data protection issues in this sector. However, the application of this large corpus of documents presents operational difficulties, and operators continue to lag behind in resilience to cyber attacks. This paper contributes a systematization of the significant cybersecurity documents relevant to the healthcare sector. We collected the 49 most significant documents and used the NIST cybersecurity framework to categorize key information and support the implementation of cybersecurity measures., Comment: 14 pages
- Published
- 2023
- Full Text
- View/download PDF
157. Constraints on the Galactic Centre environment from \textit{Gaia} hypervelocity stars III: Insights on a possible companion to Sgr A*
- Author
-
Evans, Fraser A., Rasskazov, Alexander, Remmelzwaal, Amber, Marchetti, Tommaso, Castro-Ginard, Alfred, Rossi, Elena Maria, and Bovy, Jo
- Subjects
Astrophysics - Astrophysics of Galaxies ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
We consider a scenario in which Sgr A* is in a massive black hole binary (MBHB) with an as-of-yet undetected supermassive or intermediate-mass black hole companion. Dynamical encounters between this MBHB and single stars in its immediate vicinity would eject hypervelocity stars (HVSs) with velocities beyond the Galactic escape velocity. In this work, we use existing HVS observations to constrain for the first time the existence of a companion to Sgr A*. We simulate the ejection of HVSs via the `MBHB slingshot' scenario and show that the population of HVSs detectable today depends strongly on the companion mass and the separation of the MBHB. We demonstrate that the lack of uncontroversial HVS candidates in \textit{Gaia} Data Release 3 places a firm upper limit on the mass of a possible Sgr A* companion. Within one milliparsec of Sgr A*, our results exclude a companion more massive than $1000 \, \mathrm{M_\odot}$. If Sgr A* recently merged with a companion black hole, our findings indicate that unless this companion was less massive than $500 \, \mathrm{M_\odot}$, this merger must have occurred at least $10$ Myr ago. These results complement and improve upon existing independent constraints on a companion to Sgr A* and show that large regions of its parameter space can now be ruled out., Comment: Submitted to MNRAS. 16 pages, 9 figures. Comments welcome
- Published
- 2023
- Full Text
- View/download PDF
158. Mapped Variably Scaled Kernels: Applications to Solar Imaging
- Author
-
Marchetti, Francesco, Perracchione, Emma, Volpara, Anna, Massone, Anna Maria, De Marchi, Stefano, and Piana, Michele
- Subjects
Mathematics - Numerical Analysis - Abstract
Variably scaled kernels and mapped bases constructed via the so-called fake nodes approach are two different strategies to provide adaptive bases for function interpolation. In this paper, we focus on kernel-based interpolation and we present what we call mapped variably scaled kernels, which take advantage of both strategies. We present some theoretical analysis and then we show their efficacy via numerical experiments. Moreover, we test such a new basis for image reconstruction tasks in the framework of hard X-ray astronomical imaging.
- Published
- 2023
159. Entanglement Distribution and Quantum Teleportation in Higher Dimension over the Superposition of Causal Orders of Quantum Channels
- Author
-
Dey, Indrakshi and Marchetti, Nicola
- Subjects
Quantum Physics ,Electrical Engineering and Systems Science - Systems and Control - Abstract
Multiple photonic degrees of freedom can be explored to generate high-dimensional quantum states; commonly referred to as `qudits'. Qudits offer several advantages for quantum communications, including higher information capacity, noise resilience and data throughput, and lower information loss over different propagation mediums (free space, optical fibre, underwater) as compared to conventional qubits based communication system. However, qudits have been little exploited in literature, owing to their difficulty in transmission and detection. In this paper, for the first time, we develop and formulate the theoretical framework for transmission of classical information through entanglement distribution of qudits over two quantum channels in superposition of alternative causal order. For the first time we i) engineer quantum switch operation for 2-qudit systems and ii) formulate theoretical system model for entanglement distribution of qudits via quantum switch. Results show that entanglement distribution of a qudit provides a considerable gain in fidelity even with increase in noise.
- Published
- 2023
160. MIGHTEE-\HI: Possible interactions with the galaxy NGC~895
- Author
-
Namumba, Brenda, Román, Javier, Barroso, Jesus Falcon, Knapen, Johan H., Roger, Ianjamasimanana, Naluminsa, Elizabeth, Jozsa, Gyula I. G., Korsaga, Marie, Maddox, Natasha, Frank, Brad, Sikhosana, Sinenhlanhla, Legodi, Samuel, Carignan, Claude, Ponomareva, Anastasia A., Jarrett, Tom, Lucero, Danielle, Smirnov, Oleg M., van der Hulst, Thijs, Pisano, D. J., Malek, kasia, Marchetti, Lucia, Vaccari, Mattia, Jarvis, Matt, Baes, Maarten, Meyer, Martin, Adams, Elizabeth A. K., Delhaize, Jacinta, Chen, Hao, Rajohnson, Sambatriniaina, Kurapati, Sushma, Heywood, Ian, and Verdes-Montenegro, Lourdes
- Subjects
Astrophysics - Astrophysics of Galaxies - Abstract
The transformation and evolution of a galaxy is strongly influenced by interactions with its environment. Neutral hydrogen (\HI) is an excellent way to trace these interactions. Here, we present \HI\ observations of the spiral galaxy NGC~895, which was previously thought to be isolated. High-sensitivity \HI\ observations from the MeerKAT large survey project MIGHTEE reveal possible interaction features, such as extended spiral arms, and the two newly discovered \HI\ companions, that drive us to change the narrative that it is an isolated galaxy. We combine these observations with deep optical images from the Hyper Suprime Camera to show an absence of tidal debris between NGC 895 and its companions. We do find an excess of light in the outer parts of the companion galaxy MGTH$\_$J022138.1-052631 which could be an indication of external perturbation and thus possible sign of interactions. Our analysis shows that NGC~895 is an actively star-forming galaxy with a SFR of $\mathrm{1.75 \pm 0.09 [M_{\odot}/yr]}$, a value typical for high stellar mass galaxies on the star forming main sequence. It is reasonable to state that different mechanisms may have contributed to the observed features in NGC~895 and this emphasizes the need to revisit the target with more detailed observations. Our work shows the high potential and synergy of using state-of-the-art data in both \HI\ and optical to reveal a more complete picture of galaxy environments., Comment: 14 pages, 10 figures. Accepted for publication in MNRAS
- Published
- 2023
- Full Text
- View/download PDF
161. Finite Elasticity of the Vertex Model and its Role in Rigidity of Curved Cellular Tissues
- Author
-
Hernandez, Arthur, Staddon, Michael F., Moshe, Michael, and Marchetti, M. Cristina
- Subjects
Condensed Matter - Soft Condensed Matter ,Physics - Biological Physics - Abstract
Using a mean field approach and simulation, we study the non-linear mechanical response of the vertex model (VM) of biological tissue under compression and dilation. The VM is known to exhibit a transition between rigid and fluid-like, or floppy, states driven by geometric incompatibility. Target perimeter and area set a target shape which may not be geometrically achievable, thereby engendering frustration. Previously, an asymmetry in the linear elastic response was identified at the rigidity transition between compression and dilation. Here we show and characterize how the asymmetry extends away from the transition point for finite strains. Under finite compression, an initially solid VM can totally relax perimeter tension, and thereby have reduced bulk and shear modulus. Conversely, an initially floppy VM under dilation can rigidify and have a higher bulk and shear modulus. These observations imply that re-scaling of cell area shifts the transition between rigid and floppy states. Based on this insight, we calculate the re-scaling of cell area engendered by intrinsic curvature and write a prediction for the rigidity transition in the presence of curvature. The shift of the rigidity transition in the presence of curvature for the VM provides a new metric for predicting tissue rigidity from image data for curved tissues in a manner analogous to the flat case., Comment: 10 pages, 3 figures
- Published
- 2023
162. Bright Extragalactic ALMA Redshift Survey (BEARS) III: Detailed study of emission lines from 71 Herschel targets
- Author
-
Hagimoto, M., Bakx, T. J. L. C., Serjeant, S., Bendo, G. J., Urquhart, S. A., Eales, S., Harrington, K. C., Tamura, Y., Umehata, H., Berta, S., Cooray, A. R., Cox, P., De Zotti, G., Lehnert, M. D., Riechers, D. A., Scott, D., Temi, P., van der Werf, P. P., Yang, C., Amvrosiadis, A., Andreani, P. M., Baker, A. J., Beelen, A., Borsato, E., Buat, V., Butler, K. M., Dannerbauer, H., Dunne, L., Dye, S., Enia, A. F. M., Fan, L., Gavazzi, R., Gonzalez-Nuevo, J., Harris, A. I., Herrera, C. N., Hughes, D. H., Ismail, D., Ivison, R. J., Jones, B., Kohno, K., Krips, M., Lagache, G., Marchetti, L., Massardi, M., Messias, H., Negrello, M., Neri, R., Omont, A., Perez-Fournon, I., Sedgwick, C., Smith, M. W. L., Stanley, F., Verma, A., Vlahakis, C., Ward, B., Weiner, C., Weiss, A., and Young, A. J.
- Subjects
Astrophysics - Astrophysics of Galaxies - Abstract
We analyse the molecular and atomic emission lines of 71 bright Herschel-selected galaxies between redshifts 1.4 to 4.6 detected by the Atacama Large Millimetre/submillimetre Array. These lines include a total of 156 CO, [C I], and H2O emission lines. For 46 galaxies, we detect two transitions of CO lines, and for these galaxies we find gas properties similar to those of other dusty star-forming galaxy (DSFG) samples. A comparison to photo-dissociation models suggests that most of Herschel-selected galaxies have similar interstellar medium conditions as local infrared-luminous galaxies and high-redshift DSFGs, although with denser gas and more intense far-ultraviolet radiation fields than normal star-forming galaxies. The line luminosities agree with the luminosity scaling relations across five orders of magnitude, although the star-formation and gas surface density distributions (i.e., Schmidt-Kennicutt relation) suggest a different star-formation phase in our galaxies (and other DSFGs) compared to local and low-redshift gas-rich, normal star-forming systems. The gas-to-dust ratios of these galaxies are similar to Milky Way values, with no apparent redshift evolution. Four of 46 sources appear to have CO line ratios in excess of the expected maximum (thermalized) profile, suggesting a rare phase in the evolution of DSFGs. Finally, we create a deep stacked spectrum over a wide rest-frame frequency (220-890 GHz) that reveals faint transitions from HCN and CH, in line with previous stacking experiments., Comment: 30 pages, 17 figures, accepted for publication in Monthly Notices of the Royal Astronomical Society Main Journal. Comments are warmly welcomed
- Published
- 2023
- Full Text
- View/download PDF
163. A study of carbon-rich post-AGB stars in the Milky Way to understand the production of carbonaceous dust from evolved stars
- Author
-
Tosi, Silvia, Kamath, Devika, Dell'Agli, Flavia, Van Winckel, Hans, Ventura, Paolo, Marchetti, Tommaso, Marini, Ester, and Tailo, Marco
- Subjects
Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - Astrophysics of Galaxies - Abstract
The goal of this study is to reconstruct the evolution and the dust formation processes during the final AGB phases of a sample of carbon-rich, post-AGB Galactic stars, with particular attention to the determination of the past mass-loss history. We study the IR excess of sources classified as single stars by means of dust formation modelling where dust grains form and grow in a static wind and expand from the surface of the star. The method is applied to various evolutionary stages of the final AGB phase of stars with different masses and metallicities. The detailed analysis of the SED of the sources investigated, which included the derivation of the luminosities and the dust properties, is used to infer information on mass loss, efficiency of dust formation, and wind dynamics. We confirm previous results that most of the investigated sources descend from low-mass(M<1.5Msun) progenitors that reached the C-star stage. Metal-poor carbon stars are characterised by higher IR excesses with respect to their more metal-rich counterparts of similar luminosity due to a higher surface carbon-to-oxygen excess. This work confirms previous conclusions that more luminous stars descending from higher-mass progenitors are generally more opaque due to shorter evolutionary timescales that place the dust shell closer to the central object. We also find that the mass-loss rate at the tip of the AGB phase of metal-rich low-mass carbon stars is approximately 1-1.5x10^-5Msun/yr, whereas in the metal-poor domain M~4-5x10^-5Msun/yr is required. These results indicate the need for an upwards revision of the theoretical mass-loss rates of low-mass carbon stars in the available literature, which in turn require a revised determination of carbon dust yields by AGB stars., Comment: 11 pages, 5 figures
- Published
- 2023
- Full Text
- View/download PDF
164. The commissioning phase
- Author
-
Bortoletto, F., Benetti, S., Bonanno, G., Bonoli, C., Bruno, P., Carmona, C., Conconi, P., Corcione, L., Cosentino, R., D'Alessandro, M., Dominguez, R., Fantinel, D., Galli, A., Gardiol, D., Ghedina, A., Ghinassi, F., Giro, E., Gonzales, C., Gonzalez, NI., Guerra, J., Magazzù, A., Mancini, D., Marchetti, E., Medina, J., Pasian, F., Paulli, F., Pernechele, C., Pucillo, M., Ragazzoni, R., Riverol, C., Riverol, L., Schipani, P., Smareglia, R., Tessicini, G., Trancho, G., Vuerli, C., and Zacchei, A.
- Subjects
Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
In May 1997 a consistent part of the services and structures committed to the industry had already been released to the commissioning group. The telescope itself was, with the exception of the Nasmyth derotators, motors and all the optics groups, basically ready in its mechanical parts to accept the integration of all services and control equipment. Also the verification of the cabling (interlocks, data-nets, power and controls) already mounted was started in the same period. Starting from June 1998 (telescope first-light date) the telescope went gradually in use, several nights per week, in order to test and tune the tracking and pointing system, the optics and the first derotator system (Nasmyth A station). At the end of the commissioning period and with the first scientific instruments mounted (April 1999) also the first routinely observations started. In this moment the telescope is doing astronomy 80% of time and the complete first-light instrumentation is mounted., Comment: 14 pages
- Published
- 2023
165. Mathematical Model of Quantum Channel Capacity
- Author
-
Chakraborty, Mouli, Siljak, Harun, Dey, Indrakshi, and Marchetti, Nicola
- Subjects
Computer Science - Information Theory ,Electrical Engineering and Systems Science - Signal Processing - Abstract
In this article, we are proposing a closed-form solution for the capacity of the single quantum channel. The Gaussian distributed input has been considered for the analytical calculation of the capacity. In our previous couple of papers, we invoked models for joint quantum noise and the corresponding received signals; in this current research, we proved that these models are Gaussian mixtures distributions. In this paper, we showed how to deal with both of cases, namely (I)the Gaussian mixtures distribution for scalar variables and (II) the Gaussian mixtures distribution for random vectors. Our target is to calculate the entropy of the joint noise and the entropy of the received signal in order to calculate the capacity expression of the quantum channel. The main challenge is to work with the function type of the Gaussian mixture distribution. The entropy of the Gaussian mixture distributions cannot be calculated in the closed-form solution due to the logarithm of a sum of exponential functions. As a solution, we proposed a lower bound and a upper bound for each of the entropies of joint noise and the received signal, and finally upper inequality and lower inequality lead to the upper bound for the mutual information and hence the maximum achievable data rate as the capacity. In this paper reader will able to visualize an closed-form capacity experssion which make this paper distinct from our previous works. These capacity experssion and coresses ponding bounds are calculated for both the cases: the Gaussian mixtures distribution for scalar variables and the Gaussian mixtures distribution for random vectors as well., Comment: Needs further modifications
- Published
- 2023
166. Quantum Channel Modelling by Statistical Quantum Signal Processing
- Author
-
Chakraborty, Mouli, Siljak, Harun, Dey, Indrakshi, and Marchetti, Nicola
- Subjects
Quantum Physics ,Electrical Engineering and Systems Science - Signal Processing - Abstract
In this paper we are interested to model quantum signal by statistical signal processing methods. The Gaussian distribution has been considered for the input quantum signal as Gaussian state have been proven to a type of important robust state and most of the important experiments of quantum information are done with Gaussian light. Along with that a joint noise model has been invoked, and followed by a received signal model has been formulated by using convolution of transmitted signal and joint quantum noise to realized theoretical achievable capacity of the single quantum link. In joint quantum noise model we consider the quantum Poisson noise with classical Gaussian noise. We compare the capacity of the quantum channel with respect to SNR to detect its overall tendency. In this paper we use the channel equation in terms of random variable to investigate the quantum signals and noise model statistically. These methods are proposed to develop Quantum statistical signal processing and the idea comes from the statistical signal processing., Comment: needs further modifications
- Published
- 2023
167. Moving Least Squares Approximation using Variably Scaled Discontinuous Weight Function
- Author
-
Esfahani, Mohammad Karimnejad, De Marchi, Stefano, and Marchetti, Francesco
- Subjects
Mathematics - Numerical Analysis - Abstract
Functions with discontinuities appear in many applications such as image reconstruction, signal processing, optimal control problems, interface problems, engineering applications and so on. Accurate approximation and interpolation of these functions are therefore of great importance. In this paper, we design a moving least-squares approach for scattered data approximation that incorporates the discontinuities in the weight functions. The idea is to control the influence of the data sites on the approximant, not only with regards to their distance from the evaluation point, but also with respect to the discontinuity of the underlying function. We also provide an error estimate on a suitable {\it piecewise} Sobolev Space. The numerical experiments are in compliance with the convergence rate derived theoretically.
- Published
- 2023
168. Metastatic colorectal cancer first-line treatment with bevacizumab: the impact of K-ras mutation
- Author
-
Rossi L, Veltri E, Zullo A, Zoratto F, Colonna M, Longo F, Mottolese M, Giannarelli D, Ruco L, Marchetti P, Romiti A, Barucca V, Giannini G, Bianchi L, and Tomao S
- Subjects
Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Luigi Rossi,1,2 Enzo Veltri,3 Angelo Zullo,4 Federica Zoratto,1 Maria Colonna,5 Flavia Longo,6 Marcella Mottolese,7 Diana Giannarelli,8 Luigi Ruco,9 Paolo Marchetti,10 Adriana Romiti,10 Viola Barucca,10 Giuseppe Giannini,11 Loredana Bianchi,1 Silverio Tomao1 1Department of Medico-Surgical Sciences and Biotechnologies, Sapienza University of Rome, Rome, Italy; 2Oncology Unit, ICOT Hospital, Latina, Italy; 3Oncology Unit, SM Goretti Hospital, Latina, Italy; 4Gastroenterology and Digestive Endoscopy Unit, Nuovo Regina Margherita Hospital, Rome, Italy; 5Oncology Unit, Don Luigi di Liegro Hospital, Gaeta, Italy; 6Oncology Unit, Umberto I Policlinico di Roma Hospital, Sapienza University of Rome, Rome, Italy; 7Department of Pathology, 8Biostatistics and Scientific Direction, Regina Elena National Cancer Institute, Rome, Italy; 9Department of Pathology, 10Oncology Unit, Sant'Andrea Hospital, 11Department of Pathology, Umberto I Policlinico di Roma Hospital, Sapienza University of Rome, Rome, Italy Background: Bevacizumab plus chemotherapy prolongs progression-free survival (PFS) and overall survival (OS) in metastatic colorectal cancer (mCRC). Although there is strong evidence to suggest that the mutational status of the K-ras oncogene has a role as a predictive factor for activity in patients treated with cetuximab and panitumumab, few data have been obtained in patients treated with bevacizumab. We conducted an additional retrospective analysis to investigate the prognostic value of K-ras mutation relative to mCRC first-line treatment with bevacizumab. Materials and methods: A total of 108 patients were retrospectively reviewed. K-ras status was assessed in the overall population by sequencing. Statistical association for PFS and OS was analyzed using the Kaplan–Meier method, and the prognostic role of K-ras was determined using the logrank test. Results: Median PFS was 10 months both for patients with wild-type (WT) K-ras and mutated (MT) K-ras (hazard ratio [HR] 0.94, P=0.75); neither difference in median OS was significant (27 months WT K-ras versus 26 months MT K-ras, HR 0.92; P=0.70). A further analysis was carried out in the two groups according to metastatic sites. No statistically significant difference in terms of PFS and OS was demonstrated between WT K-ras and MT K-ras with liver metastases only and in those with extrahepatic disease. Conclusion: Although further study is required, our results seem to confirm that K-ras mutation does not have a prognostic role in mCRC patients receiving first-line treatment with bevacizumab. Keywords: K-ras, bevacizumab, prognostic factor, metastatic colorectal cancer, liver metastases, extrahepatic disease
- Published
- 2013
169. Study on the Fate of the Carbopol® Polymer in the Use of Hand Sanitizer Gels: An Experimental Model to Monitor Its Physical State from Product Manufacturing up to the Final Hand Rinse
- Author
-
Marcello Marchetti, Alessandro Perini, Michela Zanella, Federico Benetti, and Daniela Donelli
- Subjects
hand sanitizer gel ,microplastics ,Carbopol FTIR ,µ-FTIR ,Biology (General) ,QH301-705.5 ,Microbiology ,QR1-502 ,Biochemistry ,QD415-436 - Abstract
Carbopol® is a typical jelly agent belonging to the family of cross-linked polyacrylic acid copolymers. It is largely used in antibacterial gels due to its self-wetting properties. In its pristine physical form, Carbopol® falls under the definition of microplastics, though significant changes could occur once added to hydroalcoholic solvents of the liquid formulations. To date, no life-cycle data regarding the physical state are available for this substance or for other similar polymers of the same chemical class. The aim of the present study was the investigation of the fate of Carbopol®-derived microplastics used in the formulation of typical hand sanitizer gels available in the Italian market, such as Amuchina® X-Germ, along the product life cycle. An experimental model was designed to detect the presence of Carbopol® microparticles from product manufacturing to the final use. FTIR and µ-FTIR were used to detect and characterize solid particles after the optimization of the sample preparation of different experimental matrices. While Carbopol® as such can be classified as a microplastic, in the commercial product, Carbopol® particles were not detected. Ten volunteers used the product according to the instructions reported on the label, and finally they rinsed their hands. Carbopol®-based particles were not detected in the water rinse, indicating that, after usage, the original form of the Carbopol microparticles was not retrieved. The study proposes, for the first time, a simple and comprehensive experimental approach to identify and characterize microplastics in finished products and along the life cycle by simulating their real-life usage. This approach could be also useful to evaluate the release of chemical components into the environment through the use of dermal products.
- Published
- 2024
- Full Text
- View/download PDF
170. Clinical impact of drug-drug interactions on abemaciclib in the real-world experience of AB-ITALY study
- Author
-
Simone Scagnoli, Simona Pisegna, Angela Toss, Roberta Caputo, Michelino De Laurentiis, Michela Palleschi, Ugo de Giorgi, Enrico Cortesi, Agnese Fabbri, Alessandra Fabi, Ida Paris, Armando Orlandi, Giuseppe Curigliano, Carmen Criscitiello, Ornella Garrone, Gianluca Tomasello, Giuliana D’Auria, Patrizia Vici, Enrico Ricevuto, Federica Domati, Claudia Piombino, Sara Parola, Roberta Scafetta, Alessio Cirillo, Beatrice Taurelli Salimbeni, Francesca Sofia Di Lisa, Lidia Strigari, Robert Preissner, Maurizio Simmaco, Daniele Santini, Paolo Marchetti, and Andrea Botticelli
- Subjects
Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Abemaciclib demonstrated clinical benefit in women affected by HR+/HER2− advanced breast cancer (aBC). Drug-drug interactions (DDIs) can lead to reduced treatment efficacy or increased toxicity. This retro-prospective study aimed to evaluate outcomes, DDIs’ impact, and toxicities of abemaciclib combined with endocrine therapy in a real-world setting. Patients from 12 referral Italian hospitals with HR+/HER2− aBC who received abemaciclib were included. Clinical data about comorbidities, concurrent medications, outcomes, and adverse events (AE) were collected. Drug-PIN® (Personalized Interactions Network) is a tool recognizing the role of multiple interactions between active and/or pro-drug forms combined with biochemical and demographic patient data. The software was used to define the Drug-PIN score and Drug-PIN tier (green, yellow, dark yellow, and red) for each patient. Univariate and multivariate analyses were performed to identify predictors of patients’ PFS or toxicity. One hundred seventy-three patients were included. 13% of patients had >75years. The overall response rate (ORR) was 63%. The general population’s median PFS (mPFS) was 22 months (mo), while mOS were not reached. Patients treated with abemaciclib in combination with AI and fulvestrant had a mPFS of 36 and 19 mo, respectively. The most common toxicities were diarrhea, asthenia, and neutropenia detected in 63%,49%, and 49% of patients. The number of concomitant medications and comorbidities were not associated with survival outcomes (22 vs 17 mo, p = 0.068, p = 0.99). Drug-PIN tier from dark yellow to red and Drug-PIN score >12 were associated with shorter PFS compared to no/low-risk DDIs and score
- Published
- 2024
- Full Text
- View/download PDF
171. Revisiting the Thomas–Fermi potential for three-dimensional condensed matter systems
- Author
-
Marchetti, Gionni
- Published
- 2024
- Full Text
- View/download PDF
172. Iron bioleaching and polymers accumulation by an extreme acidophilic bacterium
- Author
-
Marchetti, Alessandro, Kupka, Daniel, Senatore, Vittorio Giorgio, Bártová, Zuzana, Branduardi, Paola, Hagarová, Lenka, Hredzák, Slavomír, and Lotti, Marina
- Published
- 2024
- Full Text
- View/download PDF
173. Global real-world experiences with pembrolizumab in advanced urothelial carcinoma after platinum-based chemotherapy: the ARON-2 study
- Author
-
Massari, Francesco, Santoni, Matteo, Takeshita, Hideki, Okada, Yohei, Tapia, Jose Carlos, Basso, Umberto, Maruzzo, Marco, Scagliarini, Sarah, Büttner, Thomas, Fornarini, Giuseppe, Myint, Zin W., Galli, Luca, Souza, Vinicius Carrera, Pichler, Renate, De Giorgi, Ugo, Gandur, Nathalia, Lam, Elaine T., Gilbert, Danielle, Popovic, Lazar, Grande, Enrique, Mammone, Giulia, Berardi, Rossana, Crabb, Simon J., Kemp, Robert, Molina-Cerrillo, Javier, Freitas, Marcelo, Luz, Murilo, Iacovelli, Roberto, Calabrò, Fabio, Tural, Deniz, Atzori, Francesco, Küronya, Zsófia, Chiari, Rita, Campos, Saul, Caffo, Orazio, Fay, André P., Kucharz, Jakub, Zucali, Paolo Andrea, Rinck, José Augusto, Zeppellini, Annalisa, Bastos, Diogo Assed, Aurilio, Gaetano, Mota, Augusto, Trindade, Karine, Ortega, Cinzia, Sade, Juan Pablo, Rizzo, Mimma, Fiala, Ondřej, Vau, Nuno, Giannatempo, Patrizia, Barillas, Allan, Monteiro, Fernando Sabino M., Dauster, Breno, Mennitto, Alessia, Nogueira, Lucas, de Carvalho Fernandes, Roni, Seront, Emmanuel, Aceituno, Luís Garcia, Grillone, Francesco, Cutuli, Hernan Javier, Fernandez, Mauricio, Bassanelli, Maria, Kopp, Ray Manneh, Roviello, Giandomenico, Abahssain, Halima, Procopio, Giuseppe, Milella, Michele, Kopecky, Jindrich, Martignetti, Angelo, Messina, Carlo, Caitano, Manuel, Inman, Eva, Kanesvaran, Ravindran, Herchhorn, Daniel, Santini, Daniele, Bamias, Aristotelis, Bisonni, Renato, Mosca, Alessandra, Morelli, Franco, Maluf, Fernando, Soares, Andrey, Nunes, Fernando, Pinto, Alvaro, Zgura, Anca, Incorvaia, Lorena, Ansari, Jawaher, Zabalza, Ignacio Ortego, Landmesser, Johannes, Rizzo, Alessandro, Mollica, Veronica, Marchetti, Andrea, Rosellini, Matteo, Sorgentoni, Giulia, Battelli, Nicola, Buti, Sebastiano, Porta, Camillo, and Bellmunt, Joaquim
- Published
- 2024
- Full Text
- View/download PDF
174. Bax Inhibitor-1 preserves pancreatic β-cell proteostasis by limiting proinsulin misfolding and programmed cell death
- Author
-
Blanc, Marina, Habbouche, Lama, Xiao, Peng, Lebeaupin, Cynthia, Janona, Marion, Vaillant, Nathalie, Irondelle, Marie, Gilleron, Jérôme, Murcy, Florent, Rousseau, Déborah, Luci, Carmelo, Barouillet, Thibault, Marchetti, Sandrine, Lacas-Gervais, Sandra, Yvan-Charvet, Laurent, Gual, Philippe, Cardozo, Alessandra K., and Bailly-Maitre, Béatrice
- Published
- 2024
- Full Text
- View/download PDF
175. Assessment of the durability of various cementitious materials subjected to low levels of H2S in wastewater networks
- Author
-
Ayoub, Janette, Guéguen-Minerbe, Marielle, Pons, Tony, Oliveira, Marcos, Guérin-Rechdaoui, Sabrina, and Marchetti, Mario
- Published
- 2024
- Full Text
- View/download PDF
176. Engineering tools for quantifying and manipulating forces in epithelia.
- Author
-
Dow, Liam, Parmar, Toshi, Marchetti, M, and Pruitt, Beth
- Abstract
The integrity of epithelia is maintained within dynamic mechanical environments during tissue development and homeostasis. Understanding how epithelial cells mechanosignal and respond collectively or individually is critical to providing insight into developmental and (patho)physiological processes. Yet, inferring or mimicking mechanical forces and downstream mechanical signaling as they occur in epithelia presents unique challenges. A variety of in vitro approaches have been used to dissect the role of mechanics in regulating epithelia organization. Here, we review approaches and results from research into how epithelial cells communicate through mechanical cues to maintain tissue organization and integrity. We summarize the unique advantages and disadvantages of various reduced-order model systems to guide researchers in choosing appropriate experimental systems. These model systems include 3D, 2D, and 1D micromanipulation methods, single cell studies, and noninvasive force inference and measurement techniques. We also highlight a number of in silico biophysical models that are informed by in vitro and in vivo observations. Together, a combination of theoretical and experimental models will aid future experiment designs and provide predictive insight into mechanically driven behaviors of epithelial dynamics.
- Published
- 2023
177. Exploring fatty acids from royal jelly as a source of histone deacetylase inhibitors: from the hive to applications in human well-being and health
- Author
-
Fernanda Aparecida dos Santos France, Debora Kazumi Maeda, Ana Beatriz Rodrigues, Mai Ono, Franciele Lopes Nogueira Marchetti, Marcos Martins Marchetti, Allana Cristina Faustino Martins, Roberto da Silva Gomes, and Cláudia Aparecida Rainho
- Subjects
Human HDACs ,10-HDA ,10-HDAA ,molecular docking ,epi-drugs ,epigenetic therapy ,Genetics ,QH426-470 - Abstract
A differential diet with royal jelly (RJ) during early larval development in honeybees shapes the phenotype, which is probably mediated by epigenetic regulation of gene expression. Evidence indicates that small molecules in RJ can modulate gene expression in mammalian cells, such as the fatty acid 10-hydroxy-2-decenoic acid (10-HDA), previously associated with the inhibition of histone deacetylase enzymes (HDACs). Therefore, we combined computational (molecular docking simulations) and experimental approaches for the screening of potential HDAC inhibitors (HDACi) among 32 RJ-derived fatty acids. Biochemical assays and gene expression analyses (Reverse Transcriptase – quantitative Polymerase Chain Reaction) were performed to evaluate the functional effects of the major RJ fatty acids, 10-HDA and 10-HDAA (10-hydroxy-decanoic acid), in two human cancer cell lines (HCT116 and MDA-MB-231). The molecular docking simulations indicate that these fatty acids might interact with class I HDACs, specifically with the catalytic domain of human HDAC2, likewise well-known HDAC inhibitors (HDACi) such as SAHA (suberoylanilide hydroxamic acid) and TSA (Trichostatin A). In addition, the combined treatment with 10-HDA and 10-HDAA inhibits the activity of human nuclear HDACs and leads to a slight increase in the expression of HDAC-coding genes in cancer cells. Our findings indicate that royal jelly fatty acids collectively contribute to HDAC inhibition and that 10-HDA and 10-HDAA are weak HDACi that facilitate the acetylation of lysine residues of chromatin, triggering an increase in gene expression levels in cancer cells.
- Published
- 2024
- Full Text
- View/download PDF
178. Early Detection and Prognostic Assessment of Cutaneous Melanoma
- Author
-
Kashani-Sabet, Mohammed, Leachman, Sancy A, Stein, Jennifer A, Arbiser, Jack L, Berry, Elizabeth G, Celebi, Julide T, Curiel-Lewandrowski, Clara, Ferris, Laura K, Grant-Kels, Jane M, Grossman, Douglas, Kulkarni, Rajan P, Marchetti, Michael A, Nelson, Kelly C, Polsky, David, Seiverling, Elizabeth V, Swetter, Susan M, Tsao, Hensin, Verdieck-Devlaeminck, Alexandra, Wei, Maria L, Bar, Anna, Bartlett, Edmund K, Bolognia, Jean L, Bowles, Tawnya L, B., Kelly, Chu, Emily Y, Hartman, Rebecca I, Hawryluk, Elena B, Jampel, Risa M, Karapetyan, Lilit, Kheterpal, Meenal, Lawson, David H, Leming, Philip D, Liebman, Tracey N, Ming, Michael E, Sahni, Debjani, Savory, Stephanie A, Shaikh, Saba S, Sober, Arthur J, Sondak, Vernon K, Spaccarelli, Natalie, Usatine, Richard P, Venna, Suraj, and Kirkwood, John M
- Subjects
Biomedical and Clinical Sciences ,Clinical Sciences ,Health Sciences ,Cancer ,Clinical Research ,Health Services ,Prevention ,4.2 Evaluation of markers and technologies ,4.1 Discovery and preclinical testing of markers and technologies ,Humans ,Skin Neoplasms ,Melanoma ,Prognosis ,Transcriptome ,Public Health ,Risk Assessment ,Melanoma ,Cutaneous Malignant ,Oncology and Carcinogenesis - Abstract
ImportanceTherapy for advanced melanoma has transformed during the past decade, but early detection and prognostic assessment of cutaneous melanoma (CM) remain paramount goals. Best practices for screening and use of pigmented lesion evaluation tools and gene expression profile (GEP) testing in CM remain to be defined.ObjectiveTo provide consensus recommendations on optimal screening practices and prebiopsy diagnostic, postbiopsy diagnostic, and prognostic assessment of CM.Evidence reviewCase scenarios were interrogated using a modified Delphi consensus method. Melanoma panelists (n = 60) were invited to vote on hypothetical scenarios via an emailed survey (n = 42), which was followed by a consensus conference (n = 51) that reviewed the literature and the rationale for survey answers. Panelists participated in a follow-up survey for final recommendations on the scenarios (n = 45).FindingsThe panelists reached consensus (≥70% agreement) in supporting a risk-stratified approach to melanoma screening in clinical settings and public screening events, screening personnel recommendations (self/partner, primary care provider, general dermatologist, and pigmented lesion expert), screening intervals, and acceptable appointment wait times. Participants also reached consensus that visual and dermoscopic examination are sufficient for evaluation and follow-up of melanocytic skin lesions deemed innocuous. The panelists reached consensus on interpreting reflectance confocal microscopy and some but not all results from epidermal tape stripping, but they did not reach consensus on use of certain pigmented lesion evaluation tools, such as electrical impedance spectroscopy. Regarding GEP scores, the panelists reached consensus that a low-risk prognostic GEP score should not outweigh concerning histologic features when selecting patients to undergo sentinel lymph node biopsy but did not reach consensus on imaging recommendations in the setting of a high-risk prognostic GEP score and low-risk histology and/or negative nodal status.Conclusions and relevanceFor this consensus statement, panelists reached consensus on aspects of a risk-stratified approach to melanoma screening and follow-up as well as use of visual examination and dermoscopy. These findings support a practical approach to diagnosing and evaluating CM. Panelists did not reach consensus on a clearly defined role for GEP testing in clinical decision-making, citing the need for additional studies to establish the clinical use of existing GEP assays.
- Published
- 2023
179. Author Correction: Graphene oxide electrodes enable electrical stimulation of distinct calcium signalling in brain astrocytes
- Author
-
Fabbri, Roberta, Scidà, Alessandra, Saracino, Emanuela, Conte, Giorgia, Kovtun, Alessandro, Candini, Andrea, Kirdajova, Denisa, Spennato, Diletta, Marchetti, Valeria, Lazzarini, Chiara, Konstantoulaki, Aikaterini, Dambruoso, Paolo, Caprini, Marco, Muccini, Michele, Ursino, Mauro, Anderova, Miroslava, Treossi, Emanuele, Zamboni, Roberto, Palermo, Vincenzo, and Benfenati, Valentina
- Published
- 2024
- Full Text
- View/download PDF
180. Simulating Electronic Absorption Spectra of Atmospherically Relevant Molecules: A Systematic Assignment for Enhancing Undergraduate STEM Education
- Author
-
Stelz-Sullivan, Eleanor J., Marchetti, Barbara, and Karsili, Tolga
- Abstract
Computational and atmospheric chemistry are two important branches of contemporary chemistry. With the present topical nature of climate change and global warming, it is more crucial than ever that students are aware of and exposed to atmospheric chemistry, with an emphasis on how modeling may aid in understanding how atmospherically relevant chemical compounds interact with incoming solar radiation. Nonetheless, computational and atmospheric chemistry are under-represented in most undergraduate chemistry curricula. In this manuscript, we describe a simple and efficient method for simulating the electronic absorption spectral profiles of atmospherically relevant molecules that may be utilized in an undergraduate computer laboratory. The laboratory results give students hands-on experience in computational and atmospheric chemistry, as well as electronic absorption spectroscopy.
- Published
- 2022
181. Electrically Small Multimodal 3D Beamforming MIMO Antenna for PHY-Layer Security
- Author
-
Zandamela, Abel, Marchetti, Nicola, and Narbudowicz, Adam
- Subjects
Electrical Engineering and Systems Science - Signal Processing - Abstract
This work proposes an electrically small 3D beamforming antenna for PHYsical Layer (PHY-layer) security. The antenna comprises two layers of stacked patch structures and is a five-mode five-port MIMO system operating around 1.85 GHz with electrical size ${ka=0.98}$ and radiation efficiency of up to ${55\%}$. By studying the properties of the excited modes, phase and amplitude control allow for unidirectional beam scanning towards any direction around the elevation and azimuth planes. PHY-layer security is investigated using the directional modulation (DM) technique, which transmits unscrambled baseband constellation symbols to a pre-specified secure direction while simultaneously spatially distorting the same constellations in all other directions. Bit Error Rate (BER) calculations reveal very low values of ${2\times10^{-5}}$ for the desired direction of the legitimate receiver, with BER${<10^{-2}}$ beamwidths of ${55^{\circ}}$ and ${58^{\circ}}$ for the azimuth and elevation planes, respectively., Comment: Conference paper
- Published
- 2023
182. Data-driven kernel designs for optimized greedy schemes: A machine learning perspective
- Author
-
Wenzel, Tizian, Marchetti, Francesco, and Perracchione, Emma
- Subjects
Mathematics - Numerical Analysis - Abstract
Thanks to their easy implementation via Radial Basis Functions (RBFs), meshfree kernel methods have been proved to be an effective tool for e.g. scattered data interpolation, PDE collocation, classification and regression tasks. Their accuracy might depend on a length scale hyperparameter, which is often tuned via cross validation schemes. Here we leverage approaches and tools from the machine learning community to introduce two-layered kernel machines, which generalize the classical RBF approaches that rely on a single hyperparameter. Indeed, the proposed learning strategy returns a kernel that is optimized not only in the Euclidean directions, but that further incorporates kernel rotations. The kernel optimization is shown to be robust by using recently improved calculations of cross validation scores. Finally, the use of greedy approaches, and specifically of the Vectorial Kernel Orthogonal Greedy Algorithm (VKOGA), allows us to construct an optimized basis that adapts to the data. Beyond a rigorous analysis on the convergence of the so-constructed two-Layered (2L)-VKOGA, its benefits are highlighted on both synthesized and real benchmark data sets.
- Published
- 2023
183. Energy-Efficient Physical Layer Security for Wearable IoT Devices
- Author
-
Zandamela, Abel, Marchetti, Nicola, and Narbudowicz, Adam
- Subjects
Electrical Engineering and Systems Science - Signal Processing - Abstract
This work proposes an energy-efficient Directional Modulation (DM) scheme for on-body Internet of Things (IoT) devices. DM performance is tested using a 5-port stacked-patch MIMO antenna under two scenarios: a free space case and using a four-layer human forearm phantom to simulate the user's wrist. It is demonstrated that the scheme achieves steerable secure transmissions across the entire horizontal plane. With a low Bit Error Rate (BER) of ${1.5\times10^{-5}}$ at the desired directions, eavesdroppers experience a high error rate of up to ${0.498}$. Furthermore, this work investigates the DM performance using a subset of the stacked patches in the MIMO antenna, revealing that some combinations achieve a low BER performance using a lower antenna profile, albeit high side-lobes of BER${<10^{-2}}$ seen outside the desired region. Overall, the solution is proposed as a good candidate to enable secure wireless communications in emerging wearable IoT devices that are subject to size and energy constraints., Comment: 5 pages, conference
- Published
- 2023
184. Flexible Multimode-Based Beamforming MIMO Antenna
- Author
-
Zandamela, Abel, Marchetti, Nicola, and Narbudowicz, Adam
- Subjects
Electrical Engineering and Systems Science - Signal Processing - Abstract
This work proposes compact, flexible Multiple Input Multiple Output (MIMO) antennas. The design principle is based on the excitation of different orthogonal radiating modes within the same antenna volume. Via phase control of the excited modes, beamforming is demonstrated in azimuth and elevation planes using single-layered structures. For flexibility, the antennas are designed using Polydimethylsiloxane (PDMS) as the substrate. Numerical results demonstrate that isolation better than 23 dB is realized in all investigated antennas under different bend configurations. Moreover, the proposed technique demonstrates an antenna with unidirectional beamsteering across the entire elevation plane, and a second design realizes a bidirectional beamsteering in the horizontal plane. Overall, the results highlight the potential of multimode-based beamforming for flexible MIMO antennas in Internet of Things (IoT) systems., Comment: 5 pages, 7 figures, conference paper
- Published
- 2023
185. Equivariant Representation Learning in the Presence of Stabilizers
- Author
-
Rey, Luis Armando Pérez, Marchetti, Giovanni Luca, Kragic, Danica, Jarnikov, Dmitri, and Holenderski, Mike
- Subjects
Computer Science - Machine Learning ,Computer Science - Artificial Intelligence ,Mathematics - Group Theory - Abstract
We introduce Equivariant Isomorphic Networks (EquIN) -- a method for learning representations that are equivariant with respect to general group actions over data. Differently from existing equivariant representation learners, EquIN is suitable for group actions that are not free, i.e., that stabilize data via nontrivial symmetries. EquIN is theoretically grounded in the orbit-stabilizer theorem from group theory. This guarantees that an ideal learner infers isomorphic representations while trained on equivariance alone and thus fully extracts the geometric structure of data. We provide an empirical investigation on image datasets with rotational symmetries and show that taking stabilizers into account improves the quality of the representations., Comment: NeurIPS Workshop on Symmetry and Geometry in Neural Representations (v1), European Conference on Machine Learning and Principles and Practice of Knowledge Discovery in Databases (v2)
- Published
- 2023
186. The Bright Extragalactic ALMA Redshift Survey (BEARS) II: Millimetre photometry of gravitational lens candidates
- Author
-
Bendo, G. J., Urquhart, S. A., Serjeant, S., Bakx, T., Hagimoto, M., Cox, P., Neri, R., Lehnert, M. D., Dannerbauer, H., Amvrosiadis, A., Andreani, P., Baker, A. J., Beelen, A., Berta, S., Borsato, E., Buat, V., Butler, K. M., Cooray, A., De Zotti, G., Dunne, L., Dye, S., Eales, S., Enia, A., Fan, L., Gavazzi, R., González-Nuevo, J., Harris, A. I., Herrera, C. N., Hughes, D. H., Ismail, D., Jones, B. M., Kohno, K., Krips, M., Lagache, G., Marchetti, L., Massardi, M., Messias, H., Negrello, M., Omont, A., Pérez-Fournon, I., Riechers, D. A., Scott, D., Smith, M. W. L., Stanley, F., Tamura, Y., Temi, P., van der Werf, P., Verma, A., Vlahakis, C., Weiß, A., Yang, C., and Young, A. J.
- Subjects
Astrophysics - Astrophysics of Galaxies - Abstract
We present 101 and 151 GHz ALMA continuum images for 85 fields selected from Herschel observations that have 500 micron flux densities >80 mJy and 250-500 micron colours consistent with z > 2, most of which are expected to be gravitationally lensed or hyperluminous infrared galaxies. Approximately half of the Herschel 500 micron sources were resolved into multiple ALMA sources, but 11 of the 15 brightest 500 micron Herschel sources correspond to individual ALMA sources. For the 37 fields containing either a single source with a spectroscopic redshift or two sources with the same spectroscopic redshift, we examined the colour temperatures and dust emissivity indices. The colour temperatures only vary weakly with redshift and are statistically consistent with no redshift-dependent temperature variations, which generally corresponds to results from other samples selected in far-infrared, submillimetre, or millimetre bands but not to results from samples selected in optical or near-infrared bands. The dust emissivity indices, with very few exceptions, are largely consistent with a value of 2. We also compared spectroscopic redshifts to photometric redshifts based on spectral energy distribution templates designed for infrared-bright high-redshift galaxies. While the templates systematically underestimate the redshifts by ~15%, the inclusion of ALMA data decreases the scatter in the predicted redshifts by a factor of ~2, illustrating the potential usefulness of these millimetre data for estimating photometric redshifts., Comment: Accepted for publication in Monthly Notices of the Royal Astronomical Society
- Published
- 2023
- Full Text
- View/download PDF
187. Optical and mid-infrared line emission in nearby Seyfert galaxies
- Author
-
Feltre, A., Gruppioni, C., Marchetti, L., Mahoro, A., Salvestrini, F., Mignoli, M., Bisigello, L., Calura, F., Charlot, S., Chevallard, J., Romero-Colmenero, E., Curtis-Lake, E., Delvecchio, I., Dors, O. L., Hirschmann, M., Jarrett, T., Marchesi, S., Moloko, M. E., Plat, A., Pozzi, F., Sefako, R., Traina, A., Vaccari, M., Väisänen, P., Vallini, L., Vidal-García, A., and Vignali, C.
- Subjects
Astrophysics - Astrophysics of Galaxies - Abstract
Line ratio diagnostics provide valuable clues on the source of ionizing radiation in galaxies with intense black hole accretion and starbursting events, such as local Seyfert or galaxies at the peak of the star formation history. We aim to provide a reference joint optical and mid-IR analysis for studying AGN identification via line ratios and testing predictions from photoionization models. We obtained homogenous optical spectra with the Southern Africa Large Telescope for 42 Seyfert galaxies with Spitzer/IRS spectroscopy and X-ray to mid-IR multiband data available. After confirming the power of the main optical ([OIII]) and mid-IR ([NeV], [OIV], [NeIII]) emission lines in tracing AGN activity, we explore diagrams based on ratios of optical and mid-IR lines by exploiting photoionization models of different ionizing sources (AGN, star formation and shocks). We find that pure AGN photoionization models are good at reproducing observations of Seyfert galaxies with an AGN fractional contribution to the mid-IR (5-40 micron) emission larger than 50 per cent. For targets with a lower AGN contribution these same models do not fully reproduce the observed mid-IR line ratios. Mid-IR ratios like [NeV]/[NeII], [OIV]/[NeII] and [NeIII]/[NeII] show a dependence on the AGN fractional contribution to the mid-IR unlike optical line ratios. An additional source of ionization, either from star formation or radiative shocks, can help explain the observations in the mid-IR. Among combinations of optical and mid-IR diagnostics in line ratio diagrams, only those involving the [OI]/Halpha ratio are promising diagnostics for simultaneously unraveling the relative role of AGN, star formation and, shocks. A proper identification of the dominant ionizing source would require the exploitation of analysis tools based on advanced statistical techniques as well as spatially resolved data., Comment: 31 pages, 15 figures, 2 tables. Accepted for publication in A&A
- Published
- 2023
- Full Text
- View/download PDF
188. The intense production of silicates during the final AGB phases of intermediate mass stars
- Author
-
Marini, E., Dell'Agli, F., Kamath, D., Ventura, P., Mattsson, L., Marchetti, T., García-Hernández, D. A., Carini, R., Fabrizio, M., and Tosi, S.
- Subjects
Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - Astrophysics of Galaxies - Abstract
The formation of silicates in circumstellar envelopes of stars evolving through the AGB is still debated given the uncertainties affecting stellar evolution modelling, the description of the dust formation process, and the capability of silicate grains to accelerate stellar outflows via radiation pressure. We study the formation of dust in the winds of intermediate mass (M $\geq 4 M_{\odot}$) stars of solar metallicity while evolving through the AGB phase. We tested the different treatments of the mass-loss mechanism by this class of stars, with the aim of assessing their contribution to the general enrichment of silicates of the interstellar medium of galaxies. We consider a sub-sample of AGB stars, whose SED is characterised by deep absorption features at $10$ and $18\mu$m, which can be regarded as the class of stars providing the most relevant contribution to the silicates' production across the Universe. Results from stellar evolution and dust formation modelling were used to fit the observed SED and to reproduce, at the same time, the detected pulsation periods and the derived surface chemical composition. This analysis leads to the derivation of tight constraints on the silicates' production rates experienced by these sources during the final AGB stages. Two out of the four sources investigated are interpreted as stars currently undergoing HBB, evolving through phases close to the stage when the mass-loss rate is largest. The remaining two stars are likely evolving through the very final AGB phases, after HBB was turned off by the gradual consumption of the convective mantle. Mass-loss rates of the order of $1-2\times 10^{-4} M_{\odot}/$yr are required when looking for consistency with the observational evidence. These results indicate the need for a revision of the silicate yields by intermediate mass stars, which are found to be $\sim 3$ times higher than previously determined.
- Published
- 2023
- Full Text
- View/download PDF
189. Archaeological Sites Detection with a Human-AI Collaboration Workflow
- Author
-
Casini, Luca, Orrù, Valentina, Montanucci, Andrea, Marchetti, Nicolò, and Roccetti, Marco
- Subjects
Computer Science - Computer Vision and Pattern Recognition ,Computer Science - Machine Learning ,I.2.6 - Abstract
This paper illustrates the results obtained by using pre-trained semantic segmentation deep learning models for the detection of archaeological sites within the Mesopotamian floodplains environment. The models were fine-tuned using openly available satellite imagery and vector shapes coming from a large corpus of annotations (i.e., surveyed sites). A randomized test showed that the best model reaches a detection accuracy in the neighborhood of 80%. Integrating domain expertise was crucial to define how to build the dataset and how to evaluate the predictions, since defining if a proposed mask counts as a prediction is very subjective. Furthermore, even an inaccurate prediction can be useful when put into context and interpreted by a trained archaeologist. Coming from these considerations we close the paper with a vision for a Human-AI collaboration workflow. Starting with an annotated dataset that is refined by the human expert we obtain a model whose predictions can either be combined to create a heatmap, to be overlaid on satellite and/or aerial imagery, or alternatively can be vectorized to make further analysis in a GIS software easier and automatic. In turn, the archaeologists can analyze the predictions, organize their onsite surveys, and refine the dataset with new, corrected, annotation, Comment: 15 pages, 5 figures, 2 tables
- Published
- 2023
190. Increasing biases can be more efficient than increasing weights
- Author
-
Metta, Carlo, Fantozzi, Marco, Papini, Andrea, Amato, Gianluca, Bergamaschi, Matteo, Galfrè, Silvia Giulia, Marchetti, Alessandro, Vegliò, Michelangelo, Parton, Maurizio, and Morandin, Francesco
- Subjects
Computer Science - Neural and Evolutionary Computing ,Computer Science - Machine Learning ,I.2.6 - Abstract
We introduce a novel computational unit for neural networks that features multiple biases, challenging the traditional perceptron structure. This unit emphasizes the importance of preserving uncorrupted information as it is passed from one unit to the next, applying activation functions later in the process with specialized biases for each unit. Through both empirical and theoretical analyses, we show that by focusing on increasing biases rather than weights, there is potential for significant enhancement in a neural network model's performance. This approach offers an alternative perspective on optimizing information flow within neural networks. See source code at https://github.com/CuriosAI/dac-dev., Comment: Major rewriting. Supersedes v1 and v2. Focusing on the fact that not all parameters are born equal: biases can be more important than weights. Accordingly, new title and new abstract, and many more experiments on fully connected architectures. This is the extended version of the paper published at WACV 2024
- Published
- 2023
191. An Italian cost-effectiveness analysis of paclitaxel albumin (nab-paclitaxel) versus conventional paclitaxel for metastatic breast cancer patients: the COSTANza study
- Author
-
Lazzaro C, Bordonaro R, Cognetti F, Fabi A, De Placido S, Arpino G, Marchetti P, Botticelli A, Pronzato P, and Martelli E
- Subjects
Medicine (General) ,R5-920 ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Carlo Lazzaro,1 Roberto Bordonaro,2 Francesco Cognetti,3 Alessandra Fabi,3 Sabino De Placido,4 Grazia Arpino,4 Paolo Marchetti,5 Andrea Botticelli,5 Paolo Pronzato,6 Elisa Martelli7 1Studio di Economia Sanitaria, Milan, Italy; 2Public Hospital Trust Garibaldi, Catania, Italy; 3Istituto dei Tumori Regina Elena, Rome, Italy; 4School of Medicine, Federico II University, Naples, Italy; 5Department of Medical Oncology, School of Medicine, Sapienza University Hospital, Rome, Italy; 6Istituto di Ricovero e Cura a Carattere Scientifico, Azienda Ospedaliera Universitaria San Martino – Isituto Scientifico Tumori, Istituto Nazionale per la Ricerca sul Cancro, Genoa, Italy; 7Health Economics and Outcomes Research, Celgene Srl, Milan, Italy Purpose: Paclitaxel albumin (nab-paclitaxel) is a nanoparticle albumin-bound paclitaxel formulation aimed at increasing therapeutic index in metastatic breast cancer. When compared to conventional paclitaxel, nab-paclitaxel has a reported longer time to progression, higher response, lower incidence of neutropenia, no need for premedication, shorter time of administration, and in pretreated metastatic breast cancer patients, extended overall survival. This study investigates the cost-effectiveness of nab-paclitaxel versus conventional paclitaxel for pretreated metastatic breast cancer patients in Italy. Materials and methods: A Markov model with progression-free, progressed, and dead states was developed to estimate costs, outcomes, and quality adjusted life years over 5 years from the Italian National Health Service viewpoint. Patients were assumed to receive nab-paclitaxel 260 mg/m2 three times weekly or conventional paclitaxel 175 mg/m2 three times weekly. Data on health care resource consumption was collected from a convenience sample of five Italian centers. Resources were valued at Euro (€) 2011. Published utility weights were applied to health states to estimate the impact of response, disease progression, and adverse events on quality adjusted life years. Three sensitivity analyses tested the robustness of the base case incremental cost-effectiveness ratio (ICER). Results and conclusion: Compared to conventional paclitaxel, nab-paclitaxel gains an extra 0.165 quality adjusted life years (0.265 life years saved) and incurs additional costs of €2506 per patient treated. This translates to an ICER of €15,189 (95% confidence interval: €11,891–€28,415). One-way sensitivity analysis underscores that ICER for nab-paclitaxel remains stable despite varying taxanes cost. Threshold analysis shows that ICER for nab-paclitaxel exceeds €40,000 only if cost per mg of conventional paclitaxel is set to zero. Probabilistic sensitivity analysis highlights that nab-paclitaxel has a 0.99 probability to be cost-effective for a threshold value of €40,000 and is the optimal alternative from a threshold value of €16,316 onwards. Based on these findings, nab-paclitaxel can be considered highly cost-effective when compared to the acceptability range for ICER proposed by the Italian Health Economics Association (€25,000–€40,000). Keywords: metastatic breast cancer, nab-paclitaxel, conventional paclitaxel, cost-effectiveness analysis, Italy
- Published
- 2013
192. Patterning of morphogenetic anisotropy fields
- Author
-
Wang, Zihang, Marchetti, M. Cristina, and Brauns, Fridtjof
- Subjects
Physics - Biological Physics ,Condensed Matter - Soft Condensed Matter ,Nonlinear Sciences - Pattern Formation and Solitons - Abstract
Orientational order, encoded in anisotropic fields, plays an important role during the development of an organism. A striking example of this is the freshwater polyp Hydra, where topological defects in the muscle fiber orientation have been shown to localize to key features of the body plan. This body plan is organized by morphogen concentration gradients, raising the question how muscle fiber orientation, morphogen gradients and body shape interact. Here, we introduce a minimal model that couples nematic orientational order to the gradient of a morphogen field. We show that on a planar surface alignment to a radial concentration gradient can induce unbinding of topological defects, as observed during budding and tentacle formation in Hydra, and stabilize aster/vortex-like defects, as observed at a Hydra's mouth. On curved surfaces mimicking the morphologies of Hydra in various stages of development -- from spheroid to adult -- our model reproduces the experimentally observed reorganization of orientational order. Our results suggest how gradient alignment and curvature effects may work together to control orientational order during development and lays the foundations for future modeling efforts that will include the tissue mechanics that drive shape deformations., Comment: v2: Published version with minor revisions. v1: 12 pages, 7 figures (4 main, 3 suppl.). Movies: https://youtube.com/playlist?list=PLdejNN8-Lt6HJ52YfhyegpI0PGoRq8pSb
- Published
- 2022
- Full Text
- View/download PDF
193. Interpolation with the polynomial kernels
- Author
-
Elefante, Giacomo, Erb, Wolfgang, Marchetti, Francesco, Perracchione, Emma, Poggiali, Davide, and Santin, Gabriele
- Subjects
Mathematics - Numerical Analysis ,Computer Science - Machine Learning - Abstract
The polynomial kernels are widely used in machine learning and they are one of the default choices to develop kernel-based classification and regression models. However, they are rarely used and considered in numerical analysis due to their lack of strict positive definiteness. In particular they do not enjoy the usual property of unisolvency for arbitrary point sets, which is one of the key properties used to build kernel-based interpolation methods. This paper is devoted to establish some initial results for the study of these kernels, and their related interpolation algorithms, in the context of approximation theory. We will first prove necessary and sufficient conditions on point sets which guarantee the existence and uniqueness of an interpolant. We will then study the Reproducing Kernel Hilbert Spaces (or native spaces) of these kernels and their norms, and provide inclusion relations between spaces corresponding to different kernel parameters. With these spaces at hand, it will be further possible to derive generic error estimates which apply to sufficiently smooth functions, thus escaping the native space. Finally, we will show how to employ an efficient stable algorithm to these kernels to obtain accurate interpolants, and we will test them in some numerical experiment. After this analysis several computational and theoretical aspects remain open, and we will outline possible further research directions in a concluding section. This work builds some bridges between kernel and polynomial interpolation, two topics to which the authors, to different extents, have been introduced under the supervision or through the work of Stefano De Marchi. For this reason, they wish to dedicate this work to him in the occasion of his 60th birthday.
- Published
- 2022
- Full Text
- View/download PDF
194. Crossover from exciton polarons to trions in doped two-dimensional semiconductors at finite temperature
- Author
-
Tiene, A., Mulkerin, B. C., Levinsen, J., Parish, M. M., and Marchetti, F. M.
- Subjects
Condensed Matter - Mesoscale and Nanoscale Physics ,Condensed Matter - Quantum Gases ,Quantum Physics - Abstract
We study systematically the role of temperature in the optical response of doped two-dimensional semiconductors. By making use of a finite-temperature Fermi-polaron theory, we reveal a crossover from a quantum-degenerate regime with well-defined polaron quasiparticles to an incoherent regime at high temperature or low doping where the lowest energy "attractive" polaron quasiparticle is destroyed, becoming subsumed into a broad trion-hole continuum. We demonstrate that the crossover is accompanied by significant qualitative changes in both absorption and photoluminescence. In particular, with increasing temperature (or decreasing doping), the emission profile of the attractive branch evolves from a symmetric Lorentzian to an asymmetric peak with an exponential tail involving trions and recoil electrons at finite momentum. We discuss the effect of temperature on the coupling to light for structures embedded into a microcavity, and we show that there can exist well-defined polariton quasiparticles even when the exciton-polaron quasiparticle has been destroyed, where the transition from weak to strong light-matter coupling can be explained in terms of the polaron linewidths and spectral weights., Comment: 19 pages, 9 figures
- Published
- 2022
- Full Text
- View/download PDF
195. Exact Quantum Virial Expansion for the Optical Response of Doped Two-Dimensional Semiconductors
- Author
-
Mulkerin, B. C., Tiene, A., Marchetti, F. M., Parish, M. M., and Levinsen, J.
- Subjects
Condensed Matter - Mesoscale and Nanoscale Physics ,Condensed Matter - Quantum Gases ,Quantum Physics - Abstract
We present a quantum virial expansion for the optical response of a doped two-dimensional semiconductor. As we show, this constitutes a perturbatively exact theory in the high-temperature or low-doping regime, where the electrons' thermal wavelength is smaller than their interparticle spacing. The virial expansion predicts new features of the photoluminescence, such as a non-trivial shape of the attractive branch related to universal low-energy exciton-electron scattering and an associated shift of the attractive peak from the trion energy. Our results are in excellent agreement with recent experiments on doped monolayer MoSe$_2$ [Zipfel et al., Phys. Rev. B 105, 075311 (2022)] and they imply that the trion binding energy is likely to have been overestimated in previous measurements. Our theory furthermore allows us to formally unify two distinct theoretical pictures that have been applied to this system, with the conventional trion picture results emerging as a high-temperature and weak-interaction limit of Fermi polaron theory., Comment: 7 pages, 2 figures (published version)
- Published
- 2022
- Full Text
- View/download PDF
196. Space-Time- and Frequency- Spreading for Interference Minimization in Dense IoT
- Author
-
Dey, ndrakshi and Marchetti, Nicola
- Subjects
Computer Science - Information Theory ,Electrical Engineering and Systems Science - Signal Processing - Abstract
In this article, we propose a space spreading-assisted framework that leverages either time or frequency diversity or both to reduce interference and signal loss owing to channel impairments and facilitate the efficient operation of large-scale dense Internet-of-Things (IoT). Our approach employs dispersion of data-streams transmitted from individual IoT devices over indexed space-time (ST), space-frequency (SF) or space-time-frequency (STF) blocks. As a result, no two devices transmit on the same block; only one is activated while the rest of the devices in the network is silent, thereby minimizing possibility of interference on the transmit side. On the receive side, multiple-antenna array ameliorates performance in presence of channel impairments while exploiting array-processing gain. As interference due to superposition of multiple data-streams is killed at its root, no extra energy is wasted in fighting interference and other impairments, thereby enabling energy-efficient transmission from multiple devices over multiple access channel (MAC). To validate the proposed concept, we simulate the performance of the framework against dense IoT networks deployed in generalized indoor and outdoor scenarios in terms of probability of signal outage. Results demonstrate that our conceptualized framework benefits from interference-free transmission as well as enhancement in overall system performance.
- Published
- 2022
197. Design rules for controlling active topological defects
- Author
-
Shankar, Suraj, Scharrer, Luca V. D., Bowick, Mark J., and Marchetti, M. Cristina
- Subjects
Condensed Matter - Soft Condensed Matter ,Condensed Matter - Materials Science ,Physics - Applied Physics - Abstract
Topological defects play a central role in the physics of many materials, including magnets, superconductors and liquid crystals. In active fluids, defects become autonomous particles that spontaneously propel from internal active stresses and drive chaotic flows stirring the fluid. The intimate connection between defect textures and active flow suggests that properties of active materials can be engineered by controlling defects, but design principles for their spatiotemporal control remain elusive. Here we propose a symmetry-based additive strategy for using elementary activity patterns, as active topological tweezers, to create, move and braid such defects. By combining theory and simulations, we demonstrate how, at the collective level, spatial activity gradients act like electric fields which, when strong enough, induce an inverted topological polarization of defects, akin to a negative susceptibility dielectric. We harness this feature in a dynamic setting to collectively pattern and transport interacting active defects. Our work establishes an additive framework to sculpt flows and manipulate active defects in both space and time, paving the way to design programmable active and living materials for transport, memory and logic., Comment: 11 pages (including Methods), 5 figures. Changed title and format, final version
- Published
- 2022
- Full Text
- View/download PDF
198. The role of non-affine deformations in the elastic behavior of the cellular vertex model
- Author
-
Staddon, Michael F., Hernandez, Arthur, Bowick, Mark J., Moshe, Michael, and Marchetti, M. Cristina
- Subjects
Condensed Matter - Soft Condensed Matter ,Physics - Biological Physics - Abstract
The vertex model of epithelia describes the apical surface of a tissue as a tiling of polygonal cells, with a mechanical energy governed by deviations in cell shape from preferred, or target, area, $A_0$, and perimeter, $P_0$. The model exhibits a rigidity transition driven by geometric incompatibility as tuned by the target shape index, $p_0 = P_0 / \sqrt{A_0}$. For $p_0 > p_*(6) = \sqrt{8 \sqrt{3}} \approx 3.72$, with $p_*(6)$ the perimeter of a regular hexagon of unit area, a cell can simultaneously attain both the preferred area and preferred perimeter. As a result, the tissue is in a mechanically soft compatible state, with zero shear and Young's moduli. For $p_0 < p_*(6)$, it is geometrically impossible for any cell to realize the preferred area and perimeter simultaneously, and the tissue is in an incompatible rigid solid state. Using a mean-field approach, we present a complete analytical calculation of the linear elastic moduli of an ordered vertex model. We analyze a relaxation step that includes non-affine deformations, leading to a softer response than previously reported. The origin of the vanishing shear and Young's moduli in the compatible state is the presence of zero-energy deformations of cell shape. The bulk modulus exhibits a jump discontinuity at the transition and can be lower in the rigid state than in the fluid-like state. The Poisson's ratio can become negative which lowers the bulk and Young's moduli. Our work provides a unified treatment of linear elasticity for the vertex model and demonstrates that this linear response is protocol-dependent.
- Published
- 2022
- Full Text
- View/download PDF
199. Mean-field phase transitions in TGFT quantum gravity
- Author
-
Marchetti, Luca, Oriti, Daniele, Pithis, Andreas G. A., and Thürigen, Johannes
- Subjects
General Relativity and Quantum Cosmology ,High Energy Physics - Theory - Abstract
Controlling the continuum limit and extracting effective gravitational physics are shared challenges for quantum gravity approaches based on quantum discrete structures. The description of quantum gravity in terms of tensorial group field theory (TGFT) has recently led to much progress in its application to phenomenology, in particular cosmology. This application relies on the assumption of a phase transition to a nontrivial vacuum (condensate) state describable by mean-field theory, an assumption that is difficult to corroborate by a full renormalization group flow analysis due to the complexity of the relevant TGFT models. Here we demonstrate that this assumption is justified due to the specific ingredients of realistic quantum geometric TGFT models: combinatorially non-local interactions, matter degrees of freedom and Lorentz group data together with the encoding of micro-causality. This greatly strengthens the evidence for the existence of a meaningful continuum gravitational regime in group-field and spin-foam quantum gravity, the phenomenology of which is amenable to explicit computations in a mean-field approximation., Comment: Revised version in line with the publication in PRL
- Published
- 2022
- Full Text
- View/download PDF
200. A study of oxygen-rich post-AGB stars in the Milky Way to understand the production of silicates from evolved stars
- Author
-
Dell'Agli, F., Tosi, S., Kamath, D., Ventura, P., Van Winckel, H., Marini, E., and Marchetti, T.
- Subjects
Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - Astrophysics of Galaxies - Abstract
The study of post asymptotic giant branch (post-AGB) stars is a valuable tool to study still poorly known aspects of the evolution of the stars through the AGB. This is due to the accurate determination of their surface chemical composition and to the peculiar shape of the SED: the emission from the central star can be easily disentangled from the contribution from the dusty shell, which can then be characterized. The goal of the present study is to reconstruct the dust formation process and more generally the late phases of the evolution of O-rich stars across the AGB phase. This is performed by studying O-rich, post-AGB stars, which are analyzed in terms of their luminosity, Teff and infrared excess. We study sources classified as single, O-rich, post-AGB stars in the Galaxy, which exhibit a double-peaked (shell-type) SED. We use results from stellar evolution modelling combined with dust formation and radiative transfer modelling to reconstruct the late AGB phases and the initial contraction to the post-AGB phase. We also determine the mass-loss and dust formation rates for stars of different mass and chemical composition. The analysis of the IR excess of the post-AGB, O-rich stars examined in this study outlines an interesting complexity, in terms of the correlation between the dust in the surroundings of the stars, the evolutionary status and the progenitor's mass. The sources descending from massive AGBs (>3Msun depending on metallicity) are generally characterized by higher IR excess than the lower mass counterparts, owing to the more intense dust formation taking place during the final AGB phases. From the determination of the location of the dusty regions we deduce that the expanding velocities of the outflow change significantly from star to star. The possibility that radiation pressure is unable to accelerate the wind in the faintest objects is also commented., Comment: 11 pages, 6 figures and 1 table. Accepted for publication in A&A
- Published
- 2022
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.