9 research outputs found

    A Study of Yield Predictions for a Model of Homogeneous Self-Assembling Components

    Get PDF
    Self-assembly of homogeneous components has the advantage of being a decentralised and highly parallel method for assembling multiple target structures, and is ideal for effective large-scale manufacturing. Yet assembly yield may be negatively affected by the formation of incompatible substructures that prevent the formation of complete target structures. In this work we present physical and theoretical analysis of a simple magnetomechanical self-assembling systems exhibiting the problem of incompatible substructures in the formation of closed circular target structures out of eight homogeneous components. The assembly yield of physical experiments from 8 to 40 components is compared with the predictions of a computational model, and the model is found to accurately predict both the mean and standard deviation of the experimental yield

    Yield prediction in parallel homogeneous assembly

    Get PDF
    We investigate the parallel assembly of two-dimensional, geometrically-closed modular target structures out of homogeneous sets of macroscopic components of varying anisotropy. The yield predicted by a chemical reaction network (CRN)-based model is quantitatively shown to reproduce experimental results over a large set of conditions. Scaling laws for parallel assembling systems are then derived from the model. By extending the validity of the CRN-based modelling, this work prompts analysis and solutions to the incompatible substructure problem

    Hoverspill: a new amphibious vehicle for responding in difficult-to-access sites

    Get PDF
    Oil spill experience often shows that response activities are hampered due to the absence of operative autonomous support capable of reaching particular sites or operate in safe and efficient conditions in areas such as saltmarshes, mudflats, river banks, cliff bottoms… This is the purpose of the so-called FP7 Hoverspill project (www.hoverspill.eu), a 3-year European project that recently reached completion: to design and build a small-size amphibious vehicle designed to ensure rapid oil spill response. The result is an air-cushion vehicle (ACV), known as Hoverspill, based on the innovative MACP (Multipurpose Air Cushion Platform) developed by Hovertech and SOA. It is a completely amphibious vehicle capable of working on land and on water, usable as a pontoon in floating conditions. Its compactness makes it easy to transport by road. The project also included the design and building of a highly effective integrated O/W Turbylec separator developed by YLEC. Spill response equipment will be loaded on-board based on a modular concept enabling the vehicle to carry out specific tasks with just the required equipmen

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

    Get PDF
    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

    A Study of Yield Predictions for a Model of Homogeneous Self-Assembling Components

    No full text
    Self-assembly of homogeneous components has the advantage of being a decentralised and highly parallel method for assembling multiple target structures, and is ideal for effective large-scale manufacturing. Yet assembly yield may be negatively affected by the formation of incompatible substructures that prevent the formation of complete target structures. In this work we present physical and theoretical analysis of a simple magnetomechanical self-assembling systems exhibiting the problem of incompatible substructures in the formation of closed circular target structures out of eight homogeneous components. The assembly yield of physical experiments from 8 to 40 components is comparedwith the predictions of a computational model, and the model is found to accurately predict both the mean and standard deviation of the experimental yield.info:eu-repo/semantics/publishe

    Kinetics of orbitally shaken particles constrained to two dimensions

    Get PDF
    We present an experimental study of the kinetics of orbitally-shaken, sliding macroscopic particles confined to a two-dimensional space bounded by walls. Discounting the forcing action of the external periodic actuation, the particles undergo a qualitative transition from a ballistic to a diffusive motion regime with time. Despite the deterministic input of kinetic energy provided by the shaker, the particles show translational velocities and diffusivity consistent with a confined random walk model. Such experimental system may therefore represent a suitable macroscopic analog to investigate aspects of molecular dynamics and self-assembly.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

    Effect of centre volume on pathological outcomes and postoperative complications after surgery for colorectal cancer: results of a multicentre national study

    No full text
    Background: The association between volume, complications and pathological outcomes is still under debate regarding colorectal cancer surgery. The aim of the study was to assess the association between centre volume and severe complications, mortality, less-than-radical oncologic surgery, and indications for neoadjuvant therapy.Methods: Retrospective analysis of 16,883 colorectal cancer cases from 80 centres (2018-2021). Outcomes: 30-day mortality; Clavien-Dindo grade >2 complications; removal of >= 12 lymph nodes; non-radical resection; neoadjuvant therapy. Quartiles of hospital volumes were classified as LOW, MEDIUM, HIGH, and VERY HIGH. Independent predictors, both overall and for rectal cancer, were evaluated using logistic regression including age, gender, AJCC stage and cancer site.Results: LOW-volume centres reported a higher rate of severe postoperative complications (OR 1.50, 95% c.i. 1.15-1.096, P = 0.003). The rate of >= 12 lymph nodes removed in LOW-volume (OR 0.68, 95% c.i. 0.56-0.85, P = 12 lymph nodes removed was lower in LOW-volume than in VERY HIGH-volume centres (OR 0.57, 95% c.i. 0.41-0.80, P = 0.001). A lower rate of neoadjuvant chemoradiation was associated with HIGH (OR 0.66, 95% c.i. 0.56-0.77, P < 0.001), MEDIUM (OR 0.75, 95% c.i. 0.60-0.92, P = 0.006), and LOW (OR 0.70, 95% c.i. 0.52-0.94, P = 0.019) volume centres (vs. VERY HIGH).Conclusion: Colorectal cancer surgery in low-volume centres is at higher risk of suboptimal management, poor postoperative outcomes, and less-than-adequate oncologic resections. Centralisation of rectal cancer cases should be taken into consideration to optimise the outcomes
    corecore