78 research outputs found
Additive Manufacturing of Al Alloys and Aluminium Matrix Composites (AMCs)
In this chapter a large description of additive manufacturing techniques for obtaining Al alloys and Al matrix composites is given. Results on mechanical properties, roughness and microstructure achievable with such fabrication route on Al alloys are reported
On the Selective Laser Melting (SLM) of the AlSi10Mg Alloy: Process, Microstructure, and Mechanical Properties
The aim of this review is to analyze and to summarize the state of the art of the processing
of aluminum alloys, and in particular of the AlSi10Mg alloy, obtained by means of the Additive
Manufacturing (AM) technique known as Selective Laser Melting (SLM). This process is gaining
interest worldwide, thanks to the possibility of obtaining a freeform fabrication coupled with high
mechanical properties related to a very fine microstructure. However, SLM is very complex, from
a physical point of view, due to the interaction between a concentrated laser source and metallic
powders, and to the extremely rapid melting and the subsequent fast solidification. The effects of the
main process variables on the properties of the final parts are analyzed in this review: from the starting
powder properties, such as shape and powder size distribution, to the main process parameters, such
as laser power and speed, layer thickness, and scanning strategy. Furthermore, a detailed overview
on the microstructure of the AlSi10Mg material, with the related tensile and fatigue properties of the
final SLM parts, in some cases after different heat treatments, is presented
Association of Upfront Peptide Receptor Radionuclide Therapy With Progression-Free Survival Among Patients With Enteropancreatic Neuroendocrine Tumors
open57noIMPORTANCE Data about the optimal timing for the initiation of peptide receptor radionuclide
therapy (PRRT) for advanced, well-differentiated enteropancreatic neuroendocrine tumors
are lacking.
OBJECTIVE To evaluate the association of upfront PRRT vs upfront chemotherapy or targeted
therapy with progression-free survival (PFS) among patients with advanced enteropancreatic
neuroendocrine tumors who experienced disease progression after treatment with somatostatin
analogues (SSAs).
DESIGN, SETTING, AND PARTICIPANTS This retrospective, multicenter cohort study analyzed the
clinical records from 25 Italian oncology centers for patients aged 18 years or older who had
unresectable, locally advanced or metastatic, well-differentiated, grades 1 to 3 enteropancreatic
neuroendocrine tumors and received either PRRT or chemotherapy or targeted therapy after
experiencing disease progression after treatment with SSAs between January 24, 2000, and July 1,
2020. Propensity score matching was done to minimize the selection bias.
EXPOSURES Upfront PRRT or upfront chemotherapy or targeted therapy.
MAIN OUTCOMES AND MEASURES The main outcome was the difference in PFS among patients
who received upfront PRRT vs among those who received upfront chemotherapy or targeted
therapy. A secondary outcome was the difference in overall survival between these groups. Hazard
ratios (HRs) were fitted in a multivariable Cox proportional hazards regression model to adjust for
relevant factors associated with PFS and were corrected for interaction with these factors.
RESULTS Of 508 evaluated patients (mean ([SD] age, 55.7 [0.5] years; 278 [54.7%] were male), 329
(64.8%) received upfront PRRT and 179 (35.2%) received upfront chemotherapy or targeted
therapy. The matched group included 222 patients (124 [55.9%] male; mean [SD] age, 56.1 [0.8]
years), with 111 in each treatment group. Median PFS was longer in the PRRT group than in the
chemotherapy or targeted therapy group in the unmatched (2.5 years [95%CI, 2.3-3.0 years] vs 0.7
years [95%CI, 0.5-1.0 years]; HR, 0.35 [95%CI, 0.28-0.44; P < .001]) and matched (2.2 years [95%
CI, 1.8-2.8 years] vs 0.6 years [95%CI, 0.4-1.0 years]; HR, 0.37 [95%CI, 0.27-0.51; P < .001])
populations. No significant differences were shown in median overall survival between the PRRT and chemotherapy or targeted therapy groups in the unmatched (12.0 years [95%CI, 10.7-14.1 years] vs
11.6 years [95%CI, 9.1-13.4 years]; HR, 0.81 [95%CI, 0.62-1.06; P = .11]) and matched (12.2 years [95%
CI, 9.1-14.2 years] vs 11.5 years [95%CI, 9.2-17.9 years]; HR, 0.83 [95%CI, 0.56-1.24; P = .36])
populations. The use of upfront PRRT was independently associated with improved PFS (HR, 0.37;
95%CI, 0.26-0.51; P < .001) in multivariable analysis. After adjustment of values for interaction,
upfront PRRT was associated with longer PFS regardless of tumor functional status (functioning:
adjusted HR [aHR], 0.39 [95%CI, 0.27-0.57]; nonfunctioning: aHR, 0.29 [95%CI, 0.16-0.56]), grade
of 1 to 2 (grade 1: aHR, 0.21 [95%CI, 0.12-0.34]; grade 2: aHR, 0.52 [95%CI, 0.29-0.73]), and site of
tumor origin (pancreatic: aHR, 0.41 [95%CI, 0.24-0.61]; intestinal: aHR, 0.19 [95%CI, 0.11-0.43])
(P < .001 for all). Conversely, the advantage was not retained in grade 3 tumors (aHR, 0.31; 95%CI,
0.12-1.37; P = .13) or in tumors with a Ki-67 proliferation index greater than 10% (aHR, 0.73; 95%CI,
0.29-1.43; P = .31).
CONCLUSIONS AND RELEVANCE In this cohort study, treatment with upfront PRRT in patients
with enteropancreatic neuroendocrine tumors who had experienced disease progression with SSA
treatment was associated with significantly improved survival outcomes compared with upfront
chemotherapy or targeted therapy. Further research is needed to investigate the correct strategy,
timing, and optimal specific sequence of these therapeutic options.openPusceddu, Sara; Prinzi, Natalie; Tafuto, Salvatore; Ibrahim, Toni; Filice, Angelina; Brizzi, Maria Pia; Panzuto, Francesco; Baldari, Sergio; Grana, Chiara M.; Campana, Davide; Davì, Maria Vittoria; Giuffrida, Dario; Zatelli, Maria Chiara; Partelli, Stefano; Razzore, Paola; Marconcini, Riccardo; Massironi, Sara; Gelsomino, Fabio; Faggiano, Antongiulio; Giannetta, Elisa; Bajetta, Emilio; Grimaldi, Franco; Cives, Mauro; Cirillo, Fernando; Perfetti, Vittorio; Corti, Francesca; Ricci, Claudio; Giacomelli, Luca; Porcu, Luca; Di Maio, Massimo; Seregni, Ettore; Maccauro, Marco; Lastoria, Secondo; Bongiovanni, Alberto; Versari, Annibale; Persano, Irene; Rinzivillo, Maria; Pignata, Salvatore Antonio; Rocca, Paola Anna; Lamberti, Giuseppe; Cingarlini, Sara; Puliafito, Ivana; Ambrosio, Maria Rosaria; Zanata, Isabella; Bracigliano, Alessandra; Severi, Stefano; Spada, Francesca; Andreasi, Valentina; Modica, Roberta; Scalorbi, Federica; Milione, Massimo; Sabella, Giovanna; Coppa, Jorgelina; Casadei, Riccardo; Di Bartolomeo, Maria; Falconi, Massimo; de Braud, FilippoPusceddu, Sara; Prinzi, Natalie; Tafuto, Salvatore; Ibrahim, Toni; Filice, Angelina; Brizzi, Maria Pia; Panzuto, Francesco; Baldari, Sergio; Grana, Chiara M.; Campana, Davide; Davì, Maria Vittoria; Giuffrida, Dario; Zatelli, Maria Chiara; Partelli, Stefano; Razzore, Paola; Marconcini, Riccardo; Massironi, Sara; Gelsomino, Fabio; Faggiano, Antongiulio; Giannetta, Elisa; Bajetta, Emilio; Grimaldi, Franco; Cives, Mauro; Cirillo, Fernando; Perfetti, Vittorio; Corti, Francesca; Ricci, Claudio; Giacomelli, Luca; Porcu, Luca; Di Maio, Massimo; Seregni, Ettore; Maccauro, Marco; Lastoria, Secondo; Bongiovanni, Alberto; Versari, Annibale; Persano, Irene; Rinzivillo, Maria; Pignata, Salvatore Antonio; Rocca, Paola Anna; Lamberti, Giuseppe; Cingarlini, Sara; Puliafito, Ivana; Ambrosio, Maria Rosaria; Zanata, Isabella; Bracigliano, Alessandra; Severi, Stefano; Spada, Francesca; Andreasi, Valentina; Modica, Roberta; Scalorbi, Federica; Milione, Massimo; Sabella, Giovanna; Coppa, Jorgelina; Casadei, Riccardo; Di Bartolomeo, Maria; Falconi, Massimo; de Braud, Filipp
How future surgery will benefit from SARS-COV-2-related measures: a SPIGC survey conveying the perspective of Italian surgeons
COVID-19 negatively affected surgical activity, but the potential benefits resulting from adopted measures remain unclear. The aim of this study was to evaluate the change in surgical activity and potential benefit from COVID-19 measures in perspective of Italian surgeons on behalf of SPIGC. A nationwide online survey on surgical practice before, during, and after COVID-19 pandemic was conducted in March-April 2022 (NCT:05323851). Effects of COVID-19 hospital-related measures on surgical patients' management and personal professional development across surgical specialties were explored. Data on demographics, pre-operative/peri-operative/post-operative management, and professional development were collected. Outcomes were matched with the corresponding volume. Four hundred and seventy-three respondents were included in final analysis across 14 surgical specialties. Since SARS-CoV-2 pandemic, application of telematic consultations (4.1% vs. 21.6%; p < 0.0001) and diagnostic evaluations (16.4% vs. 42.2%; p < 0.0001) increased. Elective surgical activities significantly reduced and surgeons opted more frequently for conservative management with a possible indication for elective (26.3% vs. 35.7%; p < 0.0001) or urgent (20.4% vs. 38.5%; p < 0.0001) surgery. All new COVID-related measures are perceived to be maintained in the future. Surgeons' personal education online increased from 12.6% (pre-COVID) to 86.6% (post-COVID; p < 0.0001). Online educational activities are considered a beneficial effect from COVID pandemic (56.4%). COVID-19 had a great impact on surgical specialties, with significant reduction of operation volume. However, some forced changes turned out to be benefits. Isolation measures pushed the use of telemedicine and telemetric devices for outpatient practice and favored communication for educational purposes and surgeon-patient/family communication. From the Italian surgeons' perspective, COVID-related measures will continue to influence future surgical clinical practice
Characterization of PEMFC single cells and stacks performance and operating life via long time tests
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