3,503 research outputs found
Navier-Stokes-Voigt equations with memory in 3D lacking instantaneous kinematic viscosity
We consider a Navier-Stokes-Voigt fluid model where the instantaneous
kinematic viscosity has been completely replaced by a memory term incorporating
hereditary effects, in presence of Ekman damping. The dissipative character of
our model is weaker than the one where hereditary and instantaneous viscosity
coexist, previously studied by Gal and Tachim-Medjo. Nevertheless, we prove the
existence of a regular exponential attractor of finite fractal dimension under
rather sharp assumptions on the memory kernel.Comment: 26 page
Asymptotics of the Coleman-Gurtin model
This paper is concerned with the integrodifferential equation \partial_t
u-\Delta u -\int_0^\infty \kappa(s)\Delta u(t-s)\,\d s + \varphi(u)=f arising
in the Coleman-Gurtin's theory of heat conduction with hereditary memory, in
presence of a nonlinearity of critical growth. Rephrasing the
equation within the history space framework, we prove the existence of global
and exponential attractors of optimal regularity and finite fractal dimension
for the related solution semigroup, acting both on the basic weak-energy space
and on a more regular phase space.Comment: Accepted in Discrete and Continuous Dynamical Systems, Serie
Editorial: Gastrointestinal Surgery: Emerging techniques, controversies and state of art
Artificial intelligence; Gastrointestinal surgery; Surgical techniquesInteligencia artificial; CirugĂa gastrointestinal; TĂ©cnicas quirĂșrgicasIntel·ligĂšncia artificial; Cirurgia gastrointestinal; TĂšcniques quirĂșrgique
Evolution of Surgical Management of Hemorrhoidal Disease: An Historical Overview
Hemorrhoidal disease (HD) is the symptomatic enlargement and/or distal displacement of the normal hemorrhoidal cushions and is one of the most frequent diseases in colorectal surgery. Several surgical or office-based therapies are currently available, with the aim of being a more tailored approach. This article aimed to elucidate the historical evolution of surgical therapy for HD from ancient times, highlighting the crucial steps, controversies, and pioneers in the field. In contrast with the previous literature on the topic that is often updated to the 1990s, with the introduction of stapled hemorrhoidopexy and transanal hemorrhoidal dearterialization, this article describes all new surgical and office-based treatments introduced in the first 20 years of the 2000s
Robotic Abdominal Surgery and COVID-19: A Systematic Review of Published Literature and Peer-Reviewed Guidelines during the SARS-CoV-2 Pandemic
SARS-CoV-2; Abdominal surgery; Robotic surgerySARS-CoV-2; CirugĂa abdominal; CirugĂa robĂłticaSARS-CoV-2; Cirurgia abdominal; Cirurgia robĂČticaBackground: Significant concern emerged at the beginning of the SARS-CoV-2 pandemic regarding the safety and practicality of robotic-assisted surgery (RAS). We aimed to review reported surgical practice and peer-reviewed published review recommendations and guidelines relating to RAS during the pandemic. Methods: A systematic review was performed in keeping with PRISMA guidelines. This study was registered on Open Science Framework. Databases were searched using the following search terms: ârobotic surgeryâ, âroboticsâ, âCOVID-19â, and âSARS-CoV-2â. Firstly, articles describing any outcome from or reference to robotic surgery during the COVID-19/SARS-CoV-2 pandemic were considered for inclusion. Guidelines or review articles that outlined recommendations were included if published in a peer-reviewed journal and incorporating direct reference to RAS practice during the pandemic. The ROBINS-I (Risk of Bias in Non-Randomised Studies of Intervention) tool was used to assess the quality of surgical practice articles and guidelines and recommendation publications were assessed using the AGREE-II reporting tool. Publication trends, median time from submission to acceptance were reported along with clinical outcomes and practice recommendations. Results: Twenty-nine articles were included: 15 reporting RAS practice and 14 comprising peer-reviewed guidelines or review recommendations related to RAS during the pandemic, with multiple specialities (i.e., urology, colorectal, digestive surgery, and general minimally invasive surgery) covered. Included articles were published April 2020âDecember 2021, and the median interval from first submission to acceptance was 92 days. All surgical practice studies scored âlowâ or âmoderateâ risk of bias on the ROBINS-I assessment. All guidelines and recommendations scored âmoderately wellâ on the AGREE-II assessment; however, all underperformed in the domain of public and patient involvement. Overall, there were no increases in perioperative complication rates or mortalities in patients who underwent RAS compared to that expected in non-COVID practice. RAS was deemed safe, with recommendations for mitigation of risk of viral transmission. Conclusions: Continuation of RAS was feasible and safe during the SARS-CoV-2 pandemic where resources permitted. Post-pandemic reflections upon published robotic data and publication patterns allows us to better prepare for future events and to enhance urgent guideline design processes
Bruno da Longobucco (da Longoburgo): The first academic surgeon in the Middle Ages
Bruno da Longobucco; Surgeon; Middle AgesBruno da Longobucco; CirurgiĂ ; Edat MitjanaBruno da Longobucco; Cirujano; Edad MediaBruno da Longobucco (1200â1286 BC) was born at the turn of the 13th Century in Longobucco (Calabria, Italy), at that time named Longoburgo. He was the first academic surgeon of the Middle Ages, a period when surgery was disregarded by mainstream physicians and was the practice of barbers, charlatans and phlebotomists. After training at the medical school of Salerno and the University of Boulogne, he was one of the founders of the University of Padua and became the first Professor of Surgery. His books Chirurgia Magna and Chirurgia Parva, were ones of the most disseminated surgical texts of the Middle Ages and it is argued helped surgery regain its reputation. Despite his importance to late medieval period, he has been essentially overlooked in the records of the history of surgery. Currently, there are no articles in English about his life indexed on PubMed, Scopus or Embase. One solitary article on Bruno's life and influence was published in 1960s in a small journal in Italian, but this is no longer active and there is no electronic means to access the original article. The aim of this article is to provide education and rediscovery of the impact of this critical figure, his works and his historic role to the development and renaissance of surgery for contemporary surgeons.The authors thank the municipality of town of Longobucco (Comune di Longobucco), Italy, for the financial support to cover the publication fees of this article
Bruno da Longobucco (da Longoburgo): The first academic surgeon in the Middle Ages
Bruno da Longobucco (1200â1286 BC) was born at the turn of the 13th Century in Longobucco (Calabria, Italy), at that time named Longoburgo. He was the first academic surgeon of the Middle Ages, a period when surgery was disregarded by mainstream physicians and was the practice of barbers, charlatans and phlebotomists. After training at the medical school of Salerno and the University of Boulogne, he was one of the founders of the University of Padua and became the first Professor of Surgery. His books Chirurgia Magna and Chirurgia Parva, were ones of the most disseminated surgical texts of the Middle Ages and it is argued helped surgery regain its reputation. Despite his importance to late medieval period, he has been essentially overlooked in the records of the history of surgery. Currently, there are no articles in English about his life indexed on PubMed, Scopus or Embase. One solitary article on Bruno's life and influence was published in 1960s in a small journal in Italian, but this is no longer active and there is no electronic means to access the original article. The aim of this article is to provide education and rediscovery of the impact of this critical figure, his works and his historic role to the development and renaissance of surgery for contemporary surgeons
An international survey exploring the management of pilonidal disease
AIM: Pilonidal disease (PD) is a common debilitating condition frequently seen in surgical practice. Several available treatments carry different benefit/risk balances. The aim of this study was to snapshot the current management of PD across European countries.METHOD: Members affiliated to the European Society of Coloproctology were invited to join the survey. An invitation was extended to others via social media. The predictive power of respondents' and hospitals' demographics on the change of therapeutic approach was explored.RESULTS: Respondents (nâ=â452) were mostly men (77%), aged 26-60âyears, practising in both academic and public hospitals and with fair distribution between colorectal (51%) and general (48%) surgeons. A total of 331 (73%) respondents recommended surgery at first presentation of the disease. Up to 80% of them recommended antibiotic therapy and 95% did not use any classification of PD. A primary closure technique was the preferred procedure (29%), followed by open technique (22%), flap creation (7%), sinusectomy (7%) and marsupialization (7%). Approximately 27% of subjects would choose the same surgical technique even after a failure. Almost half (46%) perform surgery as office based. A conservative approach was negatively associated with acutely presenting PD (pâ<â0.001). Respondents who were not considering tailored surgery based on patient presentation tended to change their approach in the case of a failed procedure.CONCLUSION: With the caveat of a heterogeneous number of respondents across countries, the results of our snapshot survey may inform the development of future guidelines.</p
Sclerobanding in the treatment of second and third degree hemorrhoidal disease in high risk patients on antiplatelet/anticoagulant therapy without suspension: a pilot study
IntroductionAround 20% of population in western countries is under anticoagulant treatment. However, there is paucity of evidence about the treatment of HD in patients under anticoagulant/antiplatelet therapy, although both suspension and continuation in the perioperative period may increase the risk of severe complications. The aim of this pilot study was to confirm the feasibility and safety of sclerobanding (Combined Rubber Band Ligation with 3% Polidocanol Foam Sclerotherapy), an office-based procedure, for the treatment of second-and third-degree HD in patients under anticoagulant/antiplatelet therapy without suspension.Materials and methodsPatients affected by second-third-degree haemorrhoids unresponsive to conservative treatment and under anticoagulant/antiplatelet were enrolled between November 2019 and October 2021. Postoperative complications, readmission, mortality and reintervention during the follow-up were evaluated.ResultsFifty-one patients were recruited, 23 female (45.1%) and 28 male (54.9%), with an average age of 65 yearsâ±â11.4 SD (range 42â90). Twenty-seven patients (52.9%) had II-degree haemorrhoidal disease, and 24 (47.1%) had grade III-degree. The most frequently taken medications were dual antiplatelet therapy (51%) and new oral anticoagulants (NOACs) (21.6%). The mean follow-up was 23 months. No intraoperative complications were recorded. The rate of complications in the first postoperative month was 13.7%, represented by mild complications: 6 cases of moderate to severe pain and 1 case (2%) of thrombosis of a residual haemorrhoidal nodule, all regressing after conservative therapy. No severe complications were reported. Postoperative complications were not statistically significantly associated with the number of nodules treated (1, 2, or 3), the disease grade (2nd vs. 3rd) or the specific anticoagulant/antiplatelet regimen. During follow-up, 2 patients (4%) required a new procedure for recurrent bleeding: one an infrared photocoagulation as outpatient, and another a haemorrhoidectomy after 3 months. No cases of intraoperative or postoperative mortality occurred.ConclusionsSclerobanding is a safe and effective technique in treating intermediate-grade haemorrhoidal disease in patients at high risk on anticoagulant/antiplatelet therapy. Sclerobanding is repeatable, usually does not require anaesthesia, and is cost-effective. Observational multicentre studies with a larger number of patients and controlled clinical trials will be needed to confirm these results
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