22 research outputs found

    High coercitivity carbon embedded L10-FePt ferromagnetic nanoparticles

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    Stoichiometric FePt nanoparticles in the tetragonal L10 phase, (Ku = 6.6?107 erg/cm3) are one of the leading candidates for next generation high-density recording media, allowing theoretical grain stability down to 3nm [1]. As-synthesized FePt nanoparticles produced by the conventional soft chemical route (polyol process) [2,3] shows disordered face centered cubic (fcc) structure with low Ku and superparamagnetic behavior at RT. The ordered L10 tetragonal structure is usually obtained by post-annealing in a reducing environment [4,5] giving rise to particle aggregation produced by sintering that affects significantly both the final particle size and the polidispersity. A preliminary work we performed pointed out that a direct synthesis of ferromagnetic particles, based on the decomposition of Fe(acac)3 and Pt(acac)2 in reducing solvent and inert atmosphere, is made possible by the increase of the reaction temperature at 290-330?C obtained by the use of Triton X-100 as solvent and polyvinylpyrrolidone (PVP) as protective agent. The resulting nanoparticles are ferromagnetic at RT with coercitive field (Hc) ranging from 0.4 to 1.0 KOe depending on the synthesis temperature. However, as evidenced by TEM analyses, they are magnetically aggregate and, for synthesis temperatures above 300?C, embedded in an amorphous matrix produced by partial decomposition of the solvent. These observations suggested us a novel approach to the synthesis of non-aggregate ferromagnetic nanoparticles. The basic idea is to block the nanoparticles in a rigid matrix, during the synthesis, before they become ferromagnetic, to prevent magnetic aggregation. Using PEG-600 as solvent and quickly raising the temperature above 300?C cause the polyol to condense in flakes. The rapid heating, joined to the increased viscosity, limits the diffusion of the nutrient phase to the growing nuclei, resulting in monodisperse nanoparticles, with a typical size ranging around 5nm (determined by XRD and TEM), randomly dispersed in the condensed matrix. In agreement with the XRD analysis, pointing out a disordered fcc structure, the magnetic measurements show at RT a superparamagnetic behaviour of the as-grown particles, with a blocking temperature TB of 60K and large distribution of energy barriers. The phase transformation to the ferromagnetic ordered tetragonal L10 structure is achieved by thermal annealing in dynamic high vacuum; the annealing transforms the organic matrix into amorphous carbon that preserves the original nanoparticle size and prevents the aggregation up to 1000?C, where it transforms into pyrolitic graphite. XRD shows the appearing of the L10 diffraction peaks after a 1 hour treatment at 650? and an almost complete phase transition after 4hours at the same temperature, where a coercitive field (Hc) of 2,5kOe at RT and 13kOe at 5K is detected. Annealing at higher temperatures, even if results in a further enhancement of the structural properties, gives rise to complex behaviour of the hysteresis, whose origin is still under investigation

    The photo diaries method to catch the daily experience of Italian university students during COVID-19 lockdown

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    The aim of this research was to explore Italian students’ lockdown experience during the COVID-19 pandemic to understand their emotions and the coping strategies they played out during their daily lives at home through photo diaries. The research was carried out in six Italian universities involving 109 participants. The task required each student to take one photo per day for one week in T1 and one in T2, representing their mood during their daily life at home and to give it a title and a brief description. Overall, 1,526 photographs with texts were collected. The main subjects of the photographs were objects, the most frequent coping strategy was self-distraction, and most participants expressed emotions of joy and anticipation but also sadness and fear. Then, the associations between the characteristics of their photos and the emotions and coping strategies from their diary entries were analyzed. For example, emotional support and joy were positively associated with family, pets, and food, while fear and sadness were represented with objects. Implications of the results are discussed, including considerations about using photo diaries during collective disasters

    Protocol of the Italian Radical Cystectomy Registry (RIC): a non-randomized, 24-month, multicenter study comparing robotic-assisted, laparoscopic, and open surgery for radical cystectomy in bladder cancer

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    Bladder cancer is the ninth most common type of cancer worldwide. In the past, radical cystectomy via open surgery has been considered the gold-standard treatment for muscle invasive bladder cancer. However, in recent years there has been a progressive increase in the use of robot-assisted laparoscopic radical cystectomy. The aim of the current project is to investigate the surgical, oncological, and functional outcomes of patients with bladder cancer who undergo radical cystectomy comparing three different surgical techniques (robotic-assisted, laparoscopic, and open surgery). Pre-, peri- and post-operative factors will be examined, and participants will be followed for a period of up to 24\u2009months to identify risks of mortality, oncological outcomes, hospital readmission, sexual performance, and continence

    Protocol of the Italian Radical Cystectomy Registry (RIC): a non-randomized, 24-month, multicenter study comparing robotic-assisted, laparoscopic, and open surgery for radical cystectomy in bladder cancer

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    Background: Bladder cancer is the ninth most common type of cancer worldwide. In the past, radical cystectomy via open surgery has been considered the gold-standard treatment for muscle invasive bladder cancer. However, in recent years there has been a progressive increase in the use of robot-assisted laparoscopic radical cystectomy. The aim of the current project is to investigate the surgical, oncological, and functional outcomes of patients with bladder cancer who undergo radical cystectomy comparing three different surgical techniques (robotic-assisted, laparoscopic, and open surgery). Pre-, peri- and post-operative factors will be examined, and participants will be followed for a period of up to 24 months to identify risks of mortality, oncological outcomes, hospital readmission, sexual performance, and continence. Methods: We describe a protocol for an observational, prospective, multicenter, cohort study to assess patients affected by bladder neoplasms undergoing radical cystectomy and urinary diversion. The Italian Radical Cystectomy Registry is an electronic registry to prospectively collect the data of patients undergoing radical cystectomy conducted with any technique (open, laparoscopic, robotic-assisted). Twenty-eight urology departments across Italy will provide data for the study, with the recruitment phase between 1st January 2017-31st October 2020. Information is collected from the patients at the moment of surgical intervention and during follow-up (3, 6, 12, and 24 months after radical cystectomy). Peri-operative variables include surgery time, type of urinary diversion, conversion to open surgery, bleeding, nerve sparing and lymphadenectomy. Follow-up data collection includes histological information (e.g., post-op staging, grading, and tumor histology), short- and long-term outcomes (e.g., mortality, post-op complications, hospital readmission, sexual potency, continence etc). Discussion: The current protocol aims to contribute additional data to the field concerning the short- and long-term outcomes of three different radical cystectomy surgical techniques for patients with bladder cancer, including open, laparoscopic, and robot-assisted. This is a comparative-effectiveness trial that takes into account a complex range of factors and decision making by both physicians and patients that affect their choice of surgical technique. Trial registration: ClinicalTrials.gov , NCT04228198 . Registered 14th January 2020- Retrospectively registered

    Sito del Nuovo manuale di didattica multimediale

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    Il sito è articolato in quattro sezioni: I) Il manuale, in cui viene presentato il volume di cui il sito costituisce un'estensione di rete e si dà la possibilità all'utente di scaricare e stampare in formato pdf il testo di: Premessa, Capitolo VI, Indice. II) Sitografia, dove è presentata una sitografia ragionata dei temi toccati dal manuale, organizzata in forma di base dati consultabile anche motore interno di ricerca. III) Percorsi didattici, che presenta esperienze e oggetti di didattica multimediale realizzati da lettori e utenti del manuale e ad esso ispirati. Fornisce anche, liberamente scaricabile, DidaIT, ossia un software originale (alla cui produzione ha collaborato l'équipe del Laboratorio di Tecnologie Audiovisive)per lo studio e la realizzazione di progetti di documenti di impianto ipertestuale e reticolare. IV) Forum, dove lettori del manuale e utenti del sito possono incontrarsi, discutere, scambiare impressioni e materiali.

    A robotic needle driver to facilitate vescico-urethral anastomosis during laparoscopic radical prostatectomy

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    Purpose: The completion of the vescico-urethral anastomosis (VUA) represents the most critical step of laparoscopic radical prostatectomy (LRP), and it can often discourage the use of minimally invasive surgery in less experienced laparoscopic surgeons. The aim of this paper is to evaluate the usefulness of a new robotic needle driver named Dexterite in performing the VUA after LRP.Materials and methods: This prospective randomized clinical study enrolled 40 consecutive patients eligible for LRP, which were randomized into four groups: group A, patients undergoing LRP done by an expert surgeon; group B, patients undergoing robotic-assisted radical prostatectomy (RARP) performed by the same expert surgeon; group C, patients undergoing LRP performed by a young surgeon at the beginning of the learning curve; group D, patients undergoing LRP performed by another young surgeon at the beginning of the learning curve with the aid of Dexterite needle driver for completion of the VUA. The two young urologists performed the same steps of LRP so that they are at the same step of the learning curve. All the anastomosis were performed with the same technique in order to be comparable. We use interrupted sutures with Vicryl 2/0 and a 5/8 needle; we performed the Rocco stitch technique before all the anastomosis (6) and we applied bladder neck sparing technique. All patients underwent an ultrasound control of the anastomosis on the seventh postoperative day, as we usually do (9,10). We consider continent who utilised no pad.Results: Operative VUA completion time was 24.9 vs. 25 vs. 86.7 vs. 61 minutes, respectively. When comparing VUA completion time in group 3 and 4, the use of the Dexterite needle driver resulted in a reduction in VUA time. Urinary leakage was seen in zero out of 10 patients in groups 1 and 2 and in three out of 10 and one in 10 patients, respectively, in groups 3 and 4. All urinary leakages were managed conservatively. One-year continence rates were 95%, 97%, 93% and 95%, respectively. Only one patient in group C developed a bladder neck contracture 6 months after the procedure, but he underwent adiuvant radiotherapy after surgery.Conclusions: Our data suggest that the use of Dexterite needle holder significantly reduces operative time of VUA completion and reduces the incidence of urinary leakage in laparoscopic surgeons at the beginning of the learning curve

    Progettazione e realizzazione dell'edizione on line degli insegnamenti M-PED/03 del collegio didattico Scienze della Comunicazione, a.a. 2005-2006, FacoltĂ  di Lettere e Filosofia

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    Gli studenti hanno interagito con il corpo docente e tra di loro, acquisito materiali, simulato esperienze, svolto compiti su piattaforma. Il loro grado di soddisfazione per l'esperienza, significativa sia sul piano tecnico sia su quello didattico, è stato unanimemente elevato.
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