Alternative power unit for light, commercial aircraft: design and performance modeling

ABSTRACT Developments in the field of microturbine technology and gas turbine driven aircraft has been progressing without much progress in light aircraft predominantly propelled by piston engines. Because of inhibitive maintenance and overhaul costs of such however, propulsion via a gas turbine engine has been proposed with the potential of eventually replacing current engine configurations. Subsequently, the objective was to conceptually design a replacement gas turbine engine in the 150 kW range. A selection of case studies was used to illustrate the changing technologies to illustrate the technological viability of micro-gas turbines for light aircraft. Advantages and disadvantages of both engine types were discussed and a concise description of gas turbine operations and its components was given. A brief overview of fundamentals as well as the transmission layout was also supplied. Three configurations were isolated, namely the single spool design, a twin spool design featuring a free power turbine and the effect of a fuel conserving recuperator. Calculations were performed using Microsoft Excel, which proved sufficient in effectively calculating complex formulae - even under the necessary iterative feed-back conditions the design process demanded. Eventually, variable-specific design criteria were derived regarding the three engine types. Because fuel consumption still proved inhibitive, the effect of recuperation was investigated which yielded a very competitive engine - should the possibility of recuperator technology exist on time. As a result, one particular recuperated, single spool gas turbine engine was successfully identified. Having met all the design criteria sufficiently, this preliminary prototype design was numerically described and put within context of principal, peripheral working components such as a compatible gearbox layout

Recommendations for patient involvement in health technology assessment in Central and Eastern European countries

IntroductionMeaningful patient involvement in health technology assessment (HTA) is essential in ensuring that the interests of the affected patient population, their families, and the general public are accurately reflected in coverage and reimbursement decisions. Central and Eastern European (CEE) countries are generally at less advanced stages of implementing HTA, which is particularly true for patient involvement activities. As part of the Horizon2020 HTx project, this research aimed to form recommendations for critical barriers to patient involvement in HTA in CEE countries. MethodsBuilt on previous research findings on potential barriers, a prioritisation survey was conducted online with CEE stakeholders. Recommendations for prioritised barriers were formed through a face-to-face workshop by CEE stakeholders and HTx experts. ResultsA total of 105 stakeholders from 13 CEE countries completed the prioritisation survey and identified 12 of the 22 potential barriers as highly important. The workshop had 36 participants representing 9 CEE countries, and 5 Western European countries coming together to discuss solutions in order to form recommendations based on best practices, real-life experience, and transferability aspects. Stakeholder groups involved in both phases included HTA organisation representatives, payers, patients, caregivers, patient organisation representatives, patient experts, health care providers, academic and non-academic researchers, health care consultants and health technology manufacturers/providers. As a result, 12 recommendations were formed specified to the CEE region's context, but potentially useful for a broader geographic audience. ConclusionIn this paper, we present 12 recommendations for meaningful, systematic, and sustainable patient involvement in HTA in CEE countries. Our hope is that engaging more than a hundred CEE stakeholders in the study helped to spread awareness of the importance and potential of patient involvement and that the resulting recommendations provide tangible steps for the way forward. Future studies shall focus on country-specific case studies of the implemented recommendations

von Willebrand factor antigen latex immunoassays are affected to a different extent by rheumatoid factor

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No indication of strict host associations in a widespread mycoparasite: Grapevine Powdery Mildew (Erysiphe necator) is attacked by phylogenetically distant Ampelomyces strains in the field

Pycnidial fungi belonging to the genus Ampelomyces are common intracellular mycoparasites of powdery mildews worldwide. Some strains have already been developed as commercial biocontrol agents (BCAs) of Erysiphe necator and other powdery mildew species infecting important crops. One of the basic, and still debated, questions concerning the tritrophic relationships between host plants, powdery mildew fungi, and Ampelomyces mycoparasites is whether Ampelomyces strains isolated from certain species of the Erysiphales are narrowly specialized to their original mycohosts or are generalist mycoparasites of many powdery mildew fungi. This is also important for the use of Ampelomyces strains as BCAs. To understand this relationship, the nuclear ribosomal DNA internal transcribed spacer (ITS) and partial actin gene (act1) sequences of 55 Ampelomyces strains from E. necator were analyzed together with those of 47 strains isolated from other powdery mildew species. These phylogenetic analyses distinguished five major clades and strains from E. necator that were present in all but one clade. This work was supplemented with the selection of nine inter-simple sequence repeat (ISSR) markers for strain-specific identification of Ampelomyces mycoparasites to monitor the environmental fate of strains applied as BCAs. The genetic distances among strains calculated based on ISSR patterns have also highlighted the genetic diversity of Ampelomyces mycoparasites naturally occurring in grapevine powdery mildew. Overall, this work showed that Ampelomyces strains isolated from E. necator are genetically diverse and there is no indication of strict mycohost associations in these strains. However, these results cannot rule out a certain degree of quantitative association between at least some of the Ampelomyces lineages identified in this work and their original mycohosts

Plasminogen Activator Inhibitor Type 1: A Possible Novel Biomarker of Late Pituitary Dysfunction after Mild Traumatic Brain Injury

More than 80% of traumatic brain injury (TBI) patients suffer from mild TBI (mTBI). However, even mTBI carries the risk of late pituitary dysfunction. A predictive biomarker at the time of injury that could identify patients who subsequently may develop permanent pituitary dysfunction would help to direct patients toward endocrine care. We enrolled 508 TBI patients (406 with mTBI) into our study. Blood samples were collected for identification of predictive biomarkers of late pituitary dysfunction at the time of admission. Follow-up blood samples were collected between 6 and 12 months after the TBI and were evaluated for pituitary function. Of the 406 mTBI patients, 76 were available for follow-up. Pre-existing mild pituitary dysfunction was found for 15 patients based on hormone levels at the time of injury. Of the remaining 61 patients, 10 have shown deficiency in at least one pituitary hormone: 4 had growth hormone deficiency, 3 gonadotropin, 2 thyrotropin, and 1 patient combined gonadotropin and thyrotropin deficiency. Hence, newly developed pituitary hormone deficiency was found in 16% of mTBI patients. Neither the cause of mTBI nor its complications were predictive of late pituitary dysfunction. Of the hemostasis parameters studied, lower plasminogen activator inhibitor type 1 (PAI-1) level at the time of injury was found to be predictive for the development of late pituitary dysfunction; sensitivity, specificity, and positive and negative predictive values were 80%, 67%, 32%, and 94%, respectively. Even mTBI carries a substantial risk of endocrine consequences. Serum PAI-1 level at the time of TBI may serve as a predictive biomarker of late pituitary dysfunction in mTBI patients