12 research outputs found
Nuove classi di funzioni scalari quasi concave generalizzate ed applicazioni a problemi di ottimizzazione
In this paper new classes of generalized-concave functions are introduced and studied. Moreover some properties about optimization are provided
Su alcuni limiti fondamentali: tecniche non classiche
Si calcola il limite x 0 3
lim x- sinx = 1
→ x 6
evidenziando come
detto calcolo si possa ricondurre a quello di limiti
notevoli senza utilizzare il primo teorema di de
l’Hôpital o le classi delle funzioni infinitesime dello
stesso ordine. Si prende spunto dal calcolo del limite
per riflettere sull'utilizzo, a volte fatto con
troppa disinvoltura, della sostituzione degli infiniti
e degli infinitesimi. Inoltre si presenta un risultato
teorico dal quale discende il suddetto limite e una
prova non classica dell’altro limite notevole
x
lim ln = 0
x
x
→+∞
L'ecologia torna a casa.
ItConsiderando la pandemia dovuta al Covid-19 come un'occasione per ripensare filosoficamente la casa e il rapporto con essa, questo testo propone un ribaltamento dell'analogia che fonda la parola "ecologia" e suggerisce un suo "ritorno a casa", riflettendo su come la casa sia arrivata a costituire effettivamente tutto il mondo percepito. Gli autori affrontano il problema considerando il rapporto dell'uomo con l'ambiente, le relazioni umane in società e, infine, il contesto domestico.EnConsidering the pandemic due to Covid-19 as an opportunity to philosophically rethink the home and our relationship with it, the text offers an overturning of the analogy that underlies the word "ecology" and suggests its "returning home". The authors reflect on how the house has actually come to be intended as the whole perceived world and they try to face the problem by considering the engagement between men and nature, human relations in society and, lastly, the domestic context
Learning the Social Web: a Multidisciplinary Approach
The Social Web is quickly becoming a way of life: millions of people, everywhere, use social network sites to stay connected with their friends, discover new people and activities, and share user-created contents. Moreover, the Social Web phenomenon experiments an astoundingly rapid growth that is not likely to slow down in the near future. At the same time, the borderline between social networks and social media is more and more blurred. This complex and evolving scenario requires a new generation of computer scientists and engineers that understand how to properly design software for supporting and fostering social interactions. This paper describes a university-level experience started four academic years ago with a Social Web course. The course uses a multidisciplinary and active learning approach by requesting the students to design and prototype a Social Web application, and the teachers provide an active support and follow-up along the semester. The paper presents the adopted teaching strategies and analyzes the attained learning outcomes, both from the qualitative and quantitative point of view
Stent-assisted coil embolization of a complex wide-neck splenic artery aneurysm
We describe the endovascular treatment of a wide-neck splenic artery aneurysm (SAA) using a stent-assisted coil embolization technique. A 55-year-old woman who was admitted for intermittent epigastric pain was diagnosed with a wide-neck aneurysm of the intermediate splenic artery. The SAA had a maximum diameter of 2.2 cm and originated from a tortuous vessel. After percutaneous access through the left brachial artery, a self-expandable stent was initially deployed across the origin of the aneurysm using a 4-French platform. The aneurysm sac was subsequently filled with coils through a microcatheter. The procedure was successful with no postoperative clinical complications. Patency of splenic artery and complete exclusion of the aneurysm were confirmed by follow-up computed tomographic angiography 1 year after treatment. In challenging anatomic situations, stent-assisted coil embolization may represent a first-choice endovascular treatment option for the exclusion of SAAs
The surgical safety checklist and patient outcomes after surgery: a prospective observational cohort study, systematic review and meta-analysis
Background: The surgical safety checklist is widely used to improve the quality of perioperative care. However, clinicians continue to debate the clinical effectiveness of this tool.
Methods: Prospective analysis of data from the International Surgical Outcomes Study (ISOS), an international observational study of elective in-patient surgery, accompanied by a systematic review and meta-analysis of published literature. The exposure was surgical safety checklist use. The primary outcome was in-hospital mortality and the secondary outcome was postoperative complications. In the ISOS cohort, a multivariable multi-level generalized linear model was used to test associations. To further contextualise these findings, we included the results from the ISOS cohort in a meta-analysis. Results are reported as odds ratios (OR) with 95% confidence intervals.
Results: We included 44 814 patients from 497 hospitals in 27 countries in the ISOS analysis. There were 40 245 (89.8%) patients exposed to the checklist, whilst 7508 (16.8%) sustained ≥1 postoperative complications and 207 (0.5%) died before hospital discharge. Checklist exposure was associated with reduced mortality [odds ratio (OR) 0.49 (0.32-0.77); P<0.01], but no difference in complication rates [OR 1.02 (0.88-1.19); P=0.75]. In a systematic review, we screened 3732 records and identified 11 eligible studies of 453 292 patients including the ISOS cohort. Checklist exposure was associated with both reduced postoperative mortality [OR 0.75 (0.62-0.92); P<0.01; I2=87%] and reduced complication rates [OR 0.73 (0.61-0.88); P<0.01; I2=89%).
Conclusions: Patients exposed to a surgical safety checklist experience better postoperative outcomes, but this could simply reflect wider quality of care in hospitals where checklist use is routine
Diagnostic and infection control strategies for Clostridioides difficile infections in a setting of high antimicrobial resistance prevalence
Clostridioides difficile (CD) is a major nosocomial pathogen and the leading cause of antibiotic-associated diarrhoea. In light of the strong association between antimicrobial use and CD infections (CDI), it may be hypothesised that areas at higher prevalence of antimicrobial resistance, like the region of Campania in southern Italy, could also have a higher rate of CDI. In this multicentre, region-based, prospective study, we analysed such issues, exploiting CDI incidence data collected from local hospitals. In 2016, the Italian National Centre for Disease Control supported a project involving three Italian regions: Friuli Venezia Giulia, Lazio and Campania. In Campania, a network of 49 hospitals willing to participate in the project was created. The project consisted of two phases: a survey on practice patterns concerning CDI and an epidemiological surveillance study. We identified a stringent need to improve awareness about CDI among the regional health-care community, as a widespread lack of surveillance programmes for CDI control was observed (existing in only 40% of participating facilities). Moreover, almost half of the participating hospitals (n=16, 43%) had no standardised procedures or protocols to control and prevent CDI. In the second phase of the study, we collected data of CDI cases during a six-month surveillance programme. In all, 87 CDI cases were observed, for a total of 903,334 patient bed-days and 122,988 admissions. According to the above data, CDI incidence was 0.96 cases/10000 patient bed-days, much lower than expected based on prior studies conducted elsewhere. The results of our study suggest CDI remains a rather neglected clinical issue in Campania. Despite a high burden of antimicrobial resistance and antimicrobial use in our geographic setting, we observed a very low incidence of CDI. Such a low incidence could be explained by underdiagnosis, but could also be related to actual diet, the lower patient age or the specific genetic background. However, further studies are warranted to either confirm or rebut the above hypotheses
A survey of clinical features of allergic rhinitis in adults
Background: Allergic rhinitis (AR) has high prevalence and substantial socio-economic burden.Material/Methods: The study included 35 Italian Centers recruiting an overall number of 3383 adult patients with rhinitis (48% males, 52% females, mean age 29.1, range 18-45 years). For each patient, the attending physician had to fill in a standardized questionnaire, covering, in particular, some issues such as the ARIA classification of allergic rhinitis (AR), the results of skin prick test (SPT), the kind of treatment, the response to treatment, and the satisfaction with treatment.Results: Out of the 3383 patients with rhinitis, 2788 (82.4%) had AR: 311 (11.5%) had a mild intermittent, 229 (8.8%) a mild persistent, 636 (23.5%) a moderate-severe intermittent, and 1518 (56.1%) a moderate-severe persistent form. The most frequently used drugs were oral antihistamines (77.1%) and topical corticosteroids (60.8%). The response to treatment was judged as excellent in 12.2%, good in 41.3%, fair in 31.2%, poor in 14.5%, and very bad in 0.8% of subjects. The rate of treatment dissatisfaction was significantly higher in patients with moderate-to-severe AR than in patients with mild AR (p<0.0001). Indication to allergen immunotherapy (AIT) was significantly more frequent (p<0.01) in patients with severe AR than with mild AR.Conclusions: These findings confirm the appropriateness of ARIA guidelines in classifying the AR patients and the association of severe symptoms with unsuccessful drug treatment. The optimal targeting of patients to be treated with AIT needs to be reassessed
Prospective observational cohort study on grading the severity of postoperative complications in global surgery research
Background
The Clavien–Dindo classification is perhaps the most widely used approach for reporting postoperative complications in clinical trials. This system classifies complication severity by the treatment provided. However, it is unclear whether the Clavien–Dindo system can be used internationally in studies across differing healthcare systems in high- (HICs) and low- and middle-income countries (LMICs).
Methods
This was a secondary analysis of the International Surgical Outcomes Study (ISOS), a prospective observational cohort study of elective surgery in adults. Data collection occurred over a 7-day period. Severity of complications was graded using Clavien–Dindo and the simpler ISOS grading (mild, moderate or severe, based on guided investigator judgement). Severity grading was compared using the intraclass correlation coefficient (ICC). Data are presented as frequencies and ICC values (with 95 per cent c.i.). The analysis was stratified by income status of the country, comparing HICs with LMICs.
Results
A total of 44 814 patients were recruited from 474 hospitals in 27 countries (19 HICs and 8 LMICs). Some 7508 patients (16·8 per cent) experienced at least one postoperative complication, equivalent to 11 664 complications in total. Using the ISOS classification, 5504 of 11 664 complications (47·2 per cent) were graded as mild, 4244 (36·4 per cent) as moderate and 1916 (16·4 per cent) as severe. Using Clavien–Dindo, 6781 of 11 664 complications (58·1 per cent) were graded as I or II, 1740 (14·9 per cent) as III, 2408 (20·6 per cent) as IV and 735 (6·3 per cent) as V. Agreement between classification systems was poor overall (ICC 0·41, 95 per cent c.i. 0·20 to 0·55), and in LMICs (ICC 0·23, 0·05 to 0·38) and HICs (ICC 0·46, 0·25 to 0·59).
Conclusion
Caution is recommended when using a treatment approach to grade complications in global surgery studies, as this may introduce bias unintentionally
The surgical safety checklist and patient outcomes after surgery: a prospective observational cohort study, systematic review and meta-analysis
© 2017 British Journal of Anaesthesia Background: The surgical safety checklist is widely used to improve the quality of perioperative care. However, clinicians continue to debate the clinical effectiveness of this tool. Methods: Prospective analysis of data from the International Surgical Outcomes Study (ISOS), an international observational study of elective in-patient surgery, accompanied by a systematic review and meta-analysis of published literature. The exposure was surgical safety checklist use. The primary outcome was in-hospital mortality and the secondary outcome was postoperative complications. In the ISOS cohort, a multivariable multi-level generalized linear model was used to test associations. To further contextualise these findings, we included the results from the ISOS cohort in a meta-analysis. Results are reported as odds ratios (OR) with 95% confidence intervals. Results: We included 44 814 patients from 497 hospitals in 27 countries in the ISOS analysis. There were 40 245 (89.8%) patients exposed to the checklist, whilst 7508 (16.8%) sustained ≥1 postoperative complications and 207 (0.5%) died before hospital discharge. Checklist exposure was associated with reduced mortality [odds ratio (OR) 0.49 (0.32–0.77); P\u3c0.01], but no difference in complication rates [OR 1.02 (0.88–1.19); P=0.75]. In a systematic review, we screened 3732 records and identified 11 eligible studies of 453 292 patients including the ISOS cohort. Checklist exposure was associated with both reduced postoperative mortality [OR 0.75 (0.62–0.92); P\u3c0.01; I2=87%] and reduced complication rates [OR 0.73 (0.61–0.88); P\u3c0.01; I2=89%). Conclusions: Patients exposed to a surgical safety checklist experience better postoperative outcomes, but this could simply reflect wider quality of care in hospitals where checklist use is routine