| 2. |
- Baldi, A., et al.
(författare)
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Mg/Ti multilayers : Structural and hydrogen absorption properties
- 2010
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Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 81:22, s. 224203-
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Tidskriftsartikel (refereegranskat)abstract
- Mg-Ti alloys have uncommon optical and hydrogen absorbing properties, originating from a "spinodal-like" microstructure with a small degree of chemical short-range order in the atomic distribution. In the present study we artificially engineer short-range order by depositing Pd-capped Mg/Ti multilayers with different periodicities. Notwithstanding the large lattice mismatch between Mg and Ti, the as-deposited metallic multilayers show good structural coherence. On exposure to H-2 gas a two-step hydrogenation process occurs with the Ti layers forming the hydride before Mg. From in situ measurements of the bilayer thickness Lambda at different hydrogen pressures, we observe large out-of-plane expansions of Mg and Ti layers on hydrogenation, indicating strong plastic deformations in the films and a consequent shortening of the coherence length. On unloading at room temperature in air, hydrogen atoms remain trapped in the Ti layers due to kinetic constraints. Such loading/unloading sequence can be explained in terms of the different thermodynamic properties of hydrogen in Mg and Ti, as shown by diffusion calculations on a model multilayered systems. Absorption isotherms measured by hydrogenography can be interpreted as a result of the elastic clamping arising from strongly bonded Mg/Pd and broken Mg/Ti interfaces.
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| 4. |
- Mege, D, et al.
(författare)
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Surgical management of esophageal sarcoma: a multicenter European experience
- 2018
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Ingår i: Diseases of the esophagus : official journal of the International Society for Diseases of the Esophagus. - : Oxford University Press (OUP). - 1442-2050. ; 31:3
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Tidskriftsartikel (refereegranskat)abstract
- Esophageal sarcomas are rare and evidence in literature is scarce making their management difficult. The objective is to report surgical and oncological outcomes of esophageal sarcoma in a large multicenter European cohort. This is a retrospective multicenter study including all patients who underwent en-bloc esophagectomy for esophageal sarcoma in seven European tertiary referral centers between 1987 and 2016. The main outcomes and measures are pathological results, early and long-term outcomes. Among 10,936 esophageal resections for cancer, 21 (0.2%) patients with esophageal sarcoma were identified. The majority of tumors was located in the middle (n = 7) and distal (n = 9) third of the esophagus. Neoadjuvant chemoradiotherapy was performed in five patients. All the patients underwent en-bloc transthoracic esophagectomy (19 open, 2 minimally invasive). Postoperative mortality occurred in 1 patient (5%). One patient received adjuvant chemotherapy. Definitive pathological results were carcinosarcoma (n = 7), leiomyosarcoma (n = 5), and other types of sarcoma (n = 9). Microscopic R1 resection was present in one patient (5%) and seven patients (33%) had positive lymph nodes. Median follow-up was 16 (3–79) months in 20 of 21 patients (95%). One-, 3-, and 5-year overall survival rates were 74%, 43%, and 35%, respectively. One-, 3- and 5-years disease-free survival rates were 58%, 40%, and 33%, respectively. Median overall survival was 6 months in N+ patients vs. 37 months for N0 patients (p = 0.06). At the end of the follow-up period, nine patients had died from cancer recurrences (43%), three patients died from other reasons (14%), one patient was still alive with recurrence (5%) and the seven remaining patients were free of disease (33%). Recurrence was local (n = 3), metastatic (n = 3), or both (n = 4). In conclusion, carcinosarcoma and leiomyosarcoma were the most common esophageal sarcoma histological subtypes. Lymph node involvement was seen in one third of cases. A transthoracic en-bloc esophagectomy with radical lymphadenectomy should be the best surgical option to achieve complete resection. Long-term survival remained poor with a high local and distant recurrence rate.
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