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An integrated turbocharger 1D design tool, allowing retrofit of both compressor and turbine is presented. An optimization procedure is employed, to design both compressor and turbine to match the entire turbocharged system in an optimal way. The optimization process focuses on engine specific fuel consumption reduction in the engine range of operation, while ensuring appropriate matching between turbomachinery components and the diesel engine. Structural integrity of both turbo-components is ensured by using simplified structural and modal analysis. Dimensionless parameters are used as optimization variables, for both compressor and turbine, allowing the design process to become fully automatic. The platform produces four optimal 1D geometries, of different possible centrifugal compressor diffuser and turbine combinations. The combination that gives the best improvement to the diesel engine operation is identified. A case study is presented, where all four turbocharger configurations are designed and analyzed aiming to at least recover the original diesel engine performance. The platform then sorts all four optimized turbocharger geometries based on annual fuel cost reduction. The best configuration achieves the largest fuel consumption reduction (0.4% for the case presented), while stable operation and structural integrity are ensured. Additionally, a study of how the new machine learning volute loss models affect the designed geometry is performed. Finally, a techno-economical assessment is performed in order to identify the most profitable retrofit option, turbocharger redesign being one of four possible turbocharger options considered by the authors. Redesigning the entire turbocharger is shown to provide the largest long term profit.

We used the Greek nationwide database to capture individuals on anti-osteoporotic treatment during 2019. From the estimated number of 683,679 osteoporotic individuals, only 42% were receiving treatment, with the total annual cost being almost one-tenth of the total cost of fractures. The treatment gap was significantly higher in males than in females.Based on the 2019 European scorecard (SCOPE), osteoporosis is diagnosed in an estimated 683,679 individuals in Greece, with the direct cost of incident fractures being €694.7 million, although further relevant real-world data are scarce.The e-Government Center for Social Security Services prescription database, which covers almost 100% of the Greek population, was used to capture all individuals on anti-osteoporotic treatment during 2019.A total of 288,983 among 8,641,341 people, corresponding to 3.3% of the total adult Greek population, had filled at least one anti-osteoporotic prescription (6.0% and 0.36% for females and males, respectively). Prevalence of anti-osteoporotic treatment increased with age, from 0.15% in those younger than 50 to 8.6% in those older than 70 years. Oral bisphosphonates were more frequently prescribed (58.8%), followed by denosumab (39.4%). Alendronate was more frequently prescribed in males and in people younger than 60 years. Denosumab was more frequently prescribed in females and in people older than 60 years. Selective estrogen-receptor modulators, teriparatide, and parenteral bisphosphonates accounted for 1.1%, 1.0%, and 0.02% of all prescriptions, respectively. Orthopedic surgeons (39.6%), endocrinologists (19.6%), general practitioners (19%), and rheumatologists (9.3%) prescribed the vast majority of anti-osteoporotic regimens, with significant differences in prescription patterns. The annual cost of treatment per patient increased significantly with age, being on average €323.33.Less than half of the estimated number of individuals with osteoporosis in 2019 in Greece received treatment, with the total annual cost being far less than the estimated cost of incident-fragility fractures. The impact of this undertreatment on related health care costs merits further investigation.

BackgroundNationwide data at a country level on Covid-19 in unvaccinated patients with rheumatoid arthritis (RA), ankylosing spondylitis (AS), psoriatic arthritis (PsA), systemic lupus erythematosus (SLE) and systemic sclerosis (SSc) are scarce.MethodsBy interlinking data from national electronic registries, covering nearly 99% of the Greek population (approximately 11,000,000), between March 2020 and February 2021, when vaccination became available, we recorded confirmed infections and Covid-19-associated hospitalizations and deaths in essentially all adult patients with RA, AS, PsA, SLE, and SSc under treatment (n=74,970, median age of 67.5, 51.2, 58.1, 56.2, 62.2 years, respectively) and in individually matched (1:5) on age, sex, and region of domicile random comparators from the general population.ResultsBinary logistic regression analysis after adjusting for age, sex and biologic agents, revealed that RA, PsA, SLE and SSc, but not AS patients, had significantly higher risk of infection (by 43%, 25%, 20% and 49%, respectively), and hospitalization for Covid-19 (by 81%, 56%, 94%, and 111%, respectively), possibly due, at least in part, to increased testing and lower threshold for admission. Patients with RA and SSc had indeed higher Covid-19 associated mortality rates [OR:1.86 (95% CI 1.37 to 2.52) and OR:2.90 (95% CI 0.97 to 8.67), respectively] compared to the general population. Each additional year of age increased the risk of hospitalization for Covid-19 by 3% (OR 1.030, 95% CI: 1.028 to 1.034) and the risk of Covid-19 related death by 8% (OR 1.08, 95% CI: 1.07 to 1.09), independently of gender, systemic rheumatic disease, and biologic agents. A further analysis using AS patients as the reference category, adjusting again for age, sex and use of biologic agents showed that patients with SSc had increased mortality (OR: 6.90, 95% CI: 1.41 to 33.72), followed by SLE (OR: 4.05 95% CI: 0.96 to 17.12) and RA patients (OR: 3.65, 95% CI: 1.06 to 12.54), whereas PsA patients had comparable mortality risk with AS patients.ConclusionComparing to the general population, Covid-19 may have a more severe impact in real-world patients with systemic rheumatic disease. Covid-19 related mortality is increased in subgroups of patients with specific rheumatic diseases, especially in older ones, underscoring the need for priority vaccination policies and access to targeted treatments.

In this paper, the main modelling aspects for setting up an Ultra-High Bypass Ratio (UHBR) Geared Turbofan (GTF) engine performance model with Variable Pitch Fan (VPF) and/or bypass Variable Area Nozzle (VAN) are first described. Next, a multi-point design (MPD) structure is presented considering performance requirements and thermal, structural and aerodynamic constraints at top-of-climb, take-off and cruise conditions. Using the MPD approach, multi-parametric studies are then carried out to generate a design space of engine cycles according to the specified targets and limits which are representative of a UHBR GTF in a narrow body aircraft for short range applications with an Entry Into Service (EIS) of 2025.

A flexible and extensible modular multi-disciplinary framework has been developed, in order to undertake design space exploration and multi-disciplinary optimization assessments of novel Ultra High Bypass Ratio (UHBR) and open rotor concepts at aircraft mission level. The framework comprises advanced engine performance simulation modelling capabilities, coupled with turbomachinery component aerodynamic design, flow path and weight estimation as well as aircraft performance, for mission level assessments. Advanced numerical solvers and optimization algorithms are integrated in the framework. The capabilities developed are used to optimize the design of a UHBR (Ultra High Bypass Ratio) geared turbofan configuration with a Variable Area Nozzle, for short/medium range applications and an EIS of 2025. The objective is to minimize the amount of fuel burn, an objective that leads to both minimum CO2 production and fuel costs. Both single and multi-objective (several missions) optimizations are performed, for representative civil aircraft missions (range from 300 nm to 4000 nm). Based on the technology level assumptions made and the constraints imposed in the design, fuel burn reduction (and therefore CO2 emissions) in excess of 18% are anticipated, compared to conventional current day engines. The work has been undertaken within Clean Sky 2 project DEMOS, in line with efforts to meet the long term ACARE targets to reduce aircraft CO2, NOx and noise emissions.