17 research outputs found
Concept design of a fast sail assisted feeder container ship
A fast sail assisted feeder container ship concept has been developed for the 2020 container market in the South East Asian and Caribbean regions.The design presented has met the requirements of an initial economic study, with a cargo capacity of 1270 twenty-foot equivalent unit containers, meeting the predictions of container throughput derived from historical data. In determining suitable vessel dimensions, account has also been taken for port and berthing restrictions, and considering hydrodynamic performance. The vessel has been designed for a maximum speed of 25 knots, allowing it to meet the demand for trade whilst reducing the number of ships operating on the routes considered.The design development of the fast feeder concept has involved rigorous analyses in a number of areas to improve the robustness of the final design. Model testing has been key to the development of the concept, by increasing confidence in the final result. This is due to the fact that other analysis techniques are not always appropriate or accurate. Two hull forms have been developed to meet requirements whilst utilising different propulsor combinations. This has enabled evaluation of efficiency gains resulting from different hydrodynamic phenomena for each design. This includes an evaluation of the hydrodynamic performance when utilising the sail system. This has been done using a combination of model test results and data from regression analysis. The final propulsor chosen is a contra-rotating podded drive arrangement. Wind tunnel testing has been used to maximise the performance of a Multi-wing sail system by investigating the effects of wing spacing, stagger and sail-container interactions. This has led to an increase in lift coefficient of 32% from initial predictions. The savings in power requirement due to the sail system are lower than initially predicted. However, another benefit of their installation, motion damping, has been identified. Whilst this has not been fully investigated, additional fuel savings are possible as well as improved seakeeping performance.The design is shown to be environmentally sustainable when compared to existing vessels operating on the proposed routes. This is largely due to the use of low-carbon and zero-sulphur fuel (liquefied natural gas) and improvements in efficiency regarding operation. This especially relates to cargo handling and scheduling. Green house gas emissions have been predicted to fall by 42% and 40% in the two regions should the design be adopted. These savings are also due to the use of the Multi-wing sail system, which contributes to reductions in power requirement of up to 6% when the vessel operates at its lower speed of 15 knots. It is demonstrated that the fast feeder is also economically feasible, with predicted daily cost savings of 27% and 33% in the South East Asian and Caribbean regions respectively. Thus the fast feeder container ship concept is a viable solution for the future of container transhipment. <br/
Concept design of a fast sail assisted feeder container ship
An environmentally sustainable fast sail-assisted feeder-container ship concept, with a maximum speed of 25 knots, has been developed for the 2020 South East Asian and Caribbean container markets. The use of low-carbon and zero-sulphur fuel (liquefied natural gas) and improvements in operational efficiency (cargo handling and scheduling) mean predicted Green house gas emissions should fall by 42% and 40% in the two selected operational regions. The adoption of a Multi-wing sail system reduces power requirement by up to 6% at the lower ship speed of 15 knots. The predicted daily cost savings are respectively 27% and 33% in South East Asian and the Caribbean regions.Two hull forms with a cargo capacity of 1270TEU utilising different propulsion combinations were initially developed to meet operational requirements. Analysis & tank testing of different hydrodynamic phenomena has enabled identification of efficiency gains for each design. The final propulsion chosen is a contra-rotating podded drive arrangement. Wind tunnel testing improved Multi-wing sail performance by investigating wing spacing, wing stagger and sail-container interactions. The associated lift coefficient was increased by 32%. Whilst savings in sail-assisted power requirement are lower than initially predicted an unexpected identified benefit was motion damping.The fast feeder-container ship is a proposed as a viable future method of container transhipment
Surgical Treatment of Angio‐Behçet
Patients with Behçet’s disease are at risk for multiple vessel‐related complications including thromboses, stenoses, occlusions, and aneurysms. Surgical treatment of Angio‐Behçet brings numerous challenges due to the peculiarities of the disease process and the high rate of complications. Recurrent vascular episodes are also quite common and Behçet patients require rigorous follow‐up. In this review, we focus on the manifestations of Behçet’s disease involving the venous system and the systemic arterial vasculitis focusing on the indications, workup, and techniques for surgical treatment. Several case studies from our own experience are presented together with supporting diagnostic imaging and the decision process whether to intervene is discussed. Although open surgery remains a valid option, new endovascular techniques are rapidly advancing and offer excellent results with important decrease in morbidity and mortality even in highly compromised patients
Improved container transshipment utilising low carbon feeder ships
Investigation of feeder ships worldwide has identified South East Asian and the Caribbean as transshipment markets open to feeder ship replacement with a need for improved operational efficiency. In response to this challenge an environmentally sustainable feeder-container ship concept has been developed for the 2020 container market. The concept utilises higher speed and larger capacity than typical feeder ships, whilst halving the fleet size. The use of low-carbon and zero-sulphur fuel (liquefied natural gas) and improvements in operational efficiency (cargo handling and scheduling) mean predicted Greenhouse gas emissions should fall by 42% and 40% in the two selected operational regions. The predicted daily cost savings are respectively 27% and 33% in South East Asian and the Caribbean. A Multi-wing sail system also contributes to these savings whilst providing the additional benefit of motion damping. Propulsion and manoeuvrability is provided through a contra-rotating podded drive. Performance predictions have been made based on physical testing of both hull form and sail system. Use of ship-borne gantry cranes and the podded based manoeuvrability permit reduced times in port, thus improving operational efficiency. A typical round trip voyage has been simulated taking into account: realistic wind and wave environment data; physical model testing data and a representative operational profile including port operations. The fast feeder-container ship is a proposed as a viable future method of container transshipment
Appendectomy versus conservative treatment with antibiotics for patients with uncomplicated acute appendicitis: a propensity score-matched analysis of patient-centered outcomes (the ACTUAA prospective multicenter trial)
Purpose: The aim of this prospective multicenter study was to compare antibiotic therapy and appendectomy as treatment for patients with uncomplicated appendicitis confirmed by ultrasound and/or computed tomography. Methods: The study was conducted from January 2017 to January 2018. Data regarding all patients discharged from the participating centers with a diagnosis of uncomplicated appendicitis were collected prospectively. Results: Of the 318 patients enrolled in the study, 27.4% underwent antibiotic-first therapy, and 72.6% underwent appendectomy. The matched group was composed of 87 patients in both study arms. Of the 87 patients available of 1-year follow-up in the antibiotic-first group, 64 (73.6%) did not require appendectomy. The complication-free treatment success in the antibiotic-first group was 64.4%. A statistically significant higher complication-free treatment success was found in the appendectomy group: 81.8% in the pre-matching sample and 83.9% in the post-matching sample. Patients in the antibiotic-first group reported lower VAS scores compared to those treated with an appendectomy, both at discharge (2.0 ± 1.7 vs 3.6 ± 2.3) and at 30-day follow-up (0.3 ± 0.6 vs 2.1 ± 1.7). The mean of the days of absence from work was higher in the appendectomy group (β 0.63; 95% CI 0.08-1.18). Conclusion: Although laparoscopic appendectomy remains the gold standard of treatment for uncomplicated appendicitis, conservative treatment with antibiotics is a safe option in most cases. Approximately 65% of patients treated with antibiotics are symptom-free at 1 year, without increased risk of adverse events should symptoms recur, and better outcomes in terms of less pain and shorter period of absence from work compared to patients undergoing an appendectomy. Trial registration: Clinicaltrials.gov identifier (NCT number): NCT03080103
Ns1 Is a Key Protein in the Vaccine Composition to Protect Ifnar(−/−) Mice against Infection with Multiple Serotypes of African Horse Sickness Virus
African horse sickness virus (AHSV) belongs to the genus Orbivirus. We have now engineered naked DNAs and recombinant modified vaccinia virus Ankara (rMVA) expressing VP2 and NS1 proteins from AHSV-4. IFNAR((−/−)) mice inoculated with DNA/rMVA-VP2,-NS1 from AHSV-4 in an heterologous prime-boost vaccination strategy generated significant levels of neutralizing antibodies specific of AHSV-4. In addition, vaccination stimulated specific T cell responses against the virus. The vaccine elicited partial protection against an homologous AHSV-4 infection and induced cross-protection against the heterologous AHSV-9. Similarly, IFNAR((−/−)) mice vaccinated with an homologous prime-boost strategy with rMVA-VP2-NS1 from AHSV-4 developed neutralizing antibodies and protective immunity against AHSV-4. Furthermore, the levels of immunity were very high since none of vaccinated animals presented viraemia when they were challenged against the homologous AHSV-4 and very low levels when they were challenged against the heterologous virus AHSV-9. These data suggest that the immunization with rMVA/rMVA was more efficient in protection against a virulent challenge with AHSV-4 and both strategies, DNA/rMVA and rMVA/rMVA, protected against the infection with AHSV-9. The inclusion of the protein NS1 in the vaccine formulations targeting AHSV generates promising multiserotype vaccines
A prospective non-randomized controlled, multicenter trial comparing Appendectomy and Conservative Treatment for Patients with Uncomplicated Acute Appendicitis (the ACTUAA study)
Purpose: Acute appendicitis (AA) is among the most common causes of lower abdominal pain and admissions to the emergency department. Over the past 20Â years, there has been a renewed interest in the conservative management of uncomplicated AA, and several studies demonstrated that an antibiotic-first strategy is a viable treatment option for uncomplicated AA. The aim of this prospective non-randomized controlled, multicenter trial is to compare antibiotic therapy and emergency appendectomy as treatment for patients with uncomplicated AA confirmed by US and/or CT or MRI scan. Methods: All adult patients in the age range 18 to 65Â years with suspected AA, consecutively admitted to the Surgical Department of the 13 participating Italian Hospitals, will be invited to take part in the study. A multicenter prospective collected registry developed by surgeons, radiologists, and pathologists with expertise in the diagnosis and treatment of uncomplicated acute appendicitis represents the best research method to assess the long-term role of antibiotics in the management of the disease. Comparison will be made between surgical and antibiotic-first approaches to uncomplicated AA through the analysis of the primary outcome measure of complication-free treatment success rate based on 1-year follow-up. Quality of life, length of hospital stay, pain evaluation, and time to return to normal activity will be evaluated as secondary outcome measures. Trial registration: Clinicaltrials.gov ID: NCT03080103