Optimization of a pseudoelastic absorber for vibration mitigation

Damic vibration absorbers (DVAs) have received special attention in recent years due to their capability to reduce structural vibrations of a primary structure. In this work, a DVA of the Tuned Mass Damper type based on a Shape Memory Alloy (SMA) element with pseudoelastic behavior is considered. Owing to their rich thermomechanical response, SMAs can exhibit hysteresis loops with rather different features in terms of overall energy dissipation and of pseudoelastic stiffness. As a first step towards the comprehensive evaluation of the performances of such a device, the optimization of a TMD based on SMA devices with different features is studied. Numerical simulations show that the size and the shape of the pseudoelastic loops can influence in a significant way the performances of the DVA

Micro-movement as an objective measure to assess autism spectrum disorder

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Minimally invasive vs. open segmental resection of the splenic flexure for cancer: a nationwide study of the Italian Society of Surgical Oncology-Colorectal Cancer Network (SICO-CNN)

Background Evidence on the efficacy of minimally invasive (MI) segmental resection of splenic flexure cancer (SFC) is not available, mostly due to the rarity of this tumor. This study aimed to determine the survival outcomes of MI and open treatment, and to investigate whether MI is noninferior to open procedure regarding short-term outcomes. Methods This nationwide retrospective cohort study included all consecutive SFC segmental resections performed in 30 referral centers between 2006 and 2016. The primary endpoint assessing efficacy was the overall survival (OS). The secondary endpoints included cancer-specific mortality (CSM), recurrence rate (RR), short-term clinical outcomes (a composite of Clavien-Dindo > 2 complications and 30-day mortality), and pathological outcomes (a composite of lymph nodes removed >= 12, and proximal and distal free resection margins length >= 5 cm). For these composites, a 6% noninferiority margin was chosen based on clinical relevance estimate. Results A total of 606 patients underwent either an open (208, 34.3%) or a MI (398, 65.7%) SFC segmental resection. At univariable analysis, OS and CSM were improved in the MI group (log-rank test p = 0.004 and Gray's tests p = 0.004, respectively), while recurrences were comparable (Gray's tests p = 0.434). Cox multivariable analysis did not support that OS and CSM were better in the MI group (p = 0.109 and p = 0.163, respectively). Successful pathological outcome, observed in 53.2% of open and 58.3% of MI resections, supported noninferiority (difference 5.1%; 1-sided 95%CI - 4.7% to infinity). Successful short-term clinical outcome was documented in 93.3% of Open and 93.0% of MI procedures, and supported noninferiority as well (difference - 0.3%; 1-sided 95%CI - 5.0% to infinity). Conclusions Among patients with SFC, the minimally invasive approach met the criterion for noninferiority for postoperative complications and pathological outcomes, and was found to provide results of OS, CSM, and RR comparable to those of open resection

Segmental transverse colectomy. Minimally invasive versus open approach: results from a multicenter collaborative study

none65noThe role of minimally invasive surgery in the treatment of transverse colon cancer is still controversial. The aim of this study is to investigate the advantages of a totally laparoscopic technique comparing open versus laparoscopic/robotic approach. Three hundred and eighty-eight patients with transverse colon cancer, treated with a segmental colon resection, were retrospectively analyzed. Demographic data, tumor stage, operative time, intraoperative complications, number of harvested lymph nodes and recovery outcomes were recorded. Recurrences and death were also evaluated during the follow-up. No differences were found between conventional and minimally invasive surgery, both for oncological long-term outcomes (recurrence rate p = 0.28; mortality p = 0.62) and postoperative complications (overall rate p = 0.43; anemia p = 0.78; nausea p = 0.68; infections p = 0.91; bleeding p = 0.62; anastomotic leak p = 0.55; ileus p = 0.75). Nevertheless, recovery outcomes showed statistically significant differences in favor of minimally invasive surgery in terms of time to first flatus (p = 0.001), tolerance to solid diet (p = 0.017), time to first mobilization (p = 0.001) and hospital stay (p = 0.004). Compared with laparoscopic approach, robotic surgery showed significantly better results for time to first flatus (p = 0.001), to first mobilization (p = 0.005) and tolerance to solid diet (p = 0.001). Finally, anastomosis evaluation confirmed the superiority of intracorporeal approach which showed significantly better results for time to first flatus (p = 0.001), to first mobilization (p = 0.003) and tolerance to solid diet (p = 0.001); moreover, we recorded a statistical difference in favor of intracorporeal approach for infection rate (p = 0.04), bleeding (p = 0.001) and anastomotic leak (p = 0.03). Minimally invasive approach is safe and effective as the conventional open surgery, with comparable oncological results but not negligible advantages in terms of recovery outcomes. Moreover, we demonstrated that robotic approach may be considered a valid option and an intracorporeal anastomosis should always be preferred.noneMilone, Marco; Degiuli, Maurizio; Velotti, Nunzio; Manigrasso, Michele; Vertaldi, Sara; D'Ugo, Domenico; De Palma, Giovanni Domenico; Dario Bruzzese, Giuseppe Servillo, Giuseppe De Simone, Katia Di Lauro, Silvia Sofia, Marco Ettore Allaix, Mario Morino, Rossella Reddavid, Carlo Alberto Ammirati, Stefano Scabini, Gabriele Anania, Cristina Bombardini, Andrea Barberis, Roberta Longhin, Andrea Belli, Francesco Bianco, Giampaolo Formisano, Giuseppe Giuliani, Paolo Pietro Bianchi, Davide Cavaliere, Leonardo Solaini, Claudio Coco, Gianluca Rizzo, Andrea Coratti, Raffaele De Luca, Michele Simone, Alberto Di Leo, Giovanni De Manzoni, Paola De Nardi, Ugo Elmore, Riccardo Rosati, Andrea Vignali, Paolo Delrio, Ugo Pace, Daniela Rega, Antonio Di Cataldo, Giovanni Li Destri, Annibale Donini, Luigina Graziosi, Andrea Fontana, Michela Mineccia, Sergio Gentilli, Manuela Monni, Mario Guerrieri, Monica Ortenzi, Francesca Pecchini, Micaela Piccoli, Italy. Corrado Pedrazzani, Giulia Turri, Sara Pollesel, Franco Roviello, Marco Rigamonti, Michele Zuolo, Mauro Santarelli, Federica Saraceno, Pierpaolo Sileri Giuseppe Sigismondo Sica, Luigi Siragusa Salvatore Pucciarelli, Matteo ZuinMilone, Marco; Degiuli, Maurizio; Velotti, Nunzio; Manigrasso, Michele; Vertaldi, Sara; D'Ugo, Domenico; De Palma, Giovanni Domenico; Dario Bruzzese, Giuseppe Servillo, Giuseppe De Simone, Katia Di Lauro, Silvia Sofia, Marco Ettore Allaix, Mario Morino, Rossella Reddavid, Carlo Alberto Ammirati, Stefano Scabini, Gabriele Anania, Cristina Bombardini, Andrea Barberis, Roberta Longhin, Andrea Belli, Francesco Bianco, Giampaolo Formisano, Giuseppe Giuliani, Paolo Pietro Bianchi, Davide Cavaliere, Leonardo Solaini, Claudio Coco, Gianluca Rizzo, Andrea Coratti, Raffaele De Luca, Michele Simone, Alberto Di Leo, Giovanni De Manzoni, Paola De Nardi, Ugo Elmore, Riccardo Rosati, Andrea Vignali, Paolo Delrio, Ugo Pace, Daniela Rega, Antonio Di Cataldo, Giovanni Li Destri, Annibale Donini, Luigina Graziosi, Andrea Fontana, Michela Mineccia, Sergio Gentilli, Manuela Monni, Mario Guerrieri, Monica Ortenzi, Francesca Pecchini, Micaela Piccoli, Italy. Corrado Pedrazzani, Giulia Turri, Sara Pollesel, Franco Roviello, Marco Rigamonti, Michele Zuolo, Mauro Santarelli, Federica Saraceno, Pierpaolo Sileri Giuseppe Sigismondo Sica, Luigi Siragusa Salvatore Pucciarelli, Matteo Zui

Colorectal Cancer Stage at Diagnosis Before vs During the COVID-19 Pandemic in Italy

IMPORTANCE Delays in screening programs and the reluctance of patients to seek medical attention because of the outbreak of SARS-CoV-2 could be associated with the risk of more advanced colorectal cancers at diagnosis. OBJECTIVE To evaluate whether the SARS-CoV-2 pandemic was associated with more advanced oncologic stage and change in clinical presentation for patients with colorectal cancer. DESIGN, SETTING, AND PARTICIPANTS This retrospective, multicenter cohort study included all 17 938 adult patients who underwent surgery for colorectal cancer from March 1, 2020, to December 31, 2021 (pandemic period), and from January 1, 2018, to February 29, 2020 (prepandemic period), in 81 participating centers in Italy, including tertiary centers and community hospitals. Follow-up was 30 days from surgery. EXPOSURES Any type of surgical procedure for colorectal cancer, including explorative surgery, palliative procedures, and atypical or segmental resections. MAIN OUTCOMES AND MEASURES The primary outcome was advanced stage of colorectal cancer at diagnosis. Secondary outcomes were distant metastasis, T4 stage, aggressive biology (defined as cancer with at least 1 of the following characteristics: signet ring cells, mucinous tumor, budding, lymphovascular invasion, perineural invasion, and lymphangitis), stenotic lesion, emergency surgery, and palliative surgery. The independent association between the pandemic period and the outcomes was assessed using multivariate random-effects logistic regression, with hospital as the cluster variable. RESULTS A total of 17 938 patients (10 007 men [55.8%]; mean [SD] age, 70.6 [12.2] years) underwent surgery for colorectal cancer: 7796 (43.5%) during the pandemic period and 10 142 (56.5%) during the prepandemic period. Logistic regression indicated that the pandemic period was significantly associated with an increased rate of advanced-stage colorectal cancer (odds ratio [OR], 1.07; 95%CI, 1.01-1.13; P = .03), aggressive biology (OR, 1.32; 95%CI, 1.15-1.53; P < .001), and stenotic lesions (OR, 1.15; 95%CI, 1.01-1.31; P = .03). CONCLUSIONS AND RELEVANCE This cohort study suggests a significant association between the SARS-CoV-2 pandemic and the risk of a more advanced oncologic stage at diagnosis among patients undergoing surgery for colorectal cancer and might indicate a potential reduction of survival for these patients

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

A comparison between different constitutive models in the analysis of the nonlinear dynamic behaviour of Shape Memory Alloys oscillators

The nonlinear dynamics of Shape Memory Alloys (SMA) oscillators has been studied by various authors since several years, by using different constitutive models for the restoring force: ranging from different kinds of internal variable models to drastically simplified polynomial models. Internal variable models are richer and can take into account most of the complex features of the SMA behavior, on the contrary, polynomial models are strongly approximate, being based on a Falk-type free energy that gives rise to a non-hysteretic non-monotonic force-displacement curve. While the two types of models give completely different results in the force-displacement-temperature space, in the nonlinear dynamics of SMA oscillators one is often interested in more global information like, for example, the determination of the maximum displacement over a periodic trajectory. Therefore one can wonder how much the fine details of the constitutive modelling actually influence the global dynamical information. To investigate this problem, in this work we compare two extreme cases of modelling: one internal variables model that takes into account hysteresis, different elastic properties of the phases, and asymmetry between tension and compression, versus a very simplified model without hysteresis which is qualitatively analogous to a polynomial one. Some sample trajectories are analysed and the whole dynamic picture is described and compared through the computation of frequency-response curves