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CO2 emission reduction of sectors such as aviation, maritime shipping, road haulage, and chemical production is challenging but necessary. Although these sectors will most likely continue to rely on carbonaceous energy carriers, they are expected to gradually shift away from fossil fuels. In order to do so, the prominent option is to utilize alternative carbon sources--like biomass and CO2 originating from carbon capture--for the production of non-fossil carbonaceous vectors (biofuels and e-fuels). However, the limited availability of biomass and the varying nature of other carbon sources necessitate a comprehensive evaluation of trade-offs between potential carbon uses and existing sources. Then, it is primordial to understand the origin of carbon used in sustainable aviation fuel (SAF) to understand the implications of defossilizing aviation for the energy system. Moreover, the production of SAF implies deep changes to the energy system that are quantified in this work. This study utilizes the linear programming cost optimization tool EnergyScope TD to analyze the holistic French energy system, encompassing transport, industry, electricity, and heat sectors while ensuring net greenhouse gas neutrality. A novel method to model and quantify carbon flows within the system is introduced, enabling a comprehensive assessment of greenhouse gas neutrality. This study highlights the significance of fulfilling clean energy requirements and implementing carbon dioxide removal measures as crucial steps toward achieving climate neutrality. Indeed, to reach climate neutrality, a production of 1,046 TWh of electricity by non-fossil sources is needed. Furthermore, the findings underscore the critical role of efficient carbon and energy valorization from biomass, providing evidence that producing fuels by combining biomass and hydrogen is optimal. The study also offers valuable insights into the future cost and impact of SAF production for air travel originating from France. That is, the European law ReFuelEU would increase the price of plane tickets by +33% and would require 126 TWh of hydrogen and 50 TWh of biomass to produce the necessary 91 TWh of jet fuel. Finally, the implications of the assumption behind the production of SAF are discussed. [ABSTRACT FROM AUTHOR]

Aviation activities have jeopardized the limited energy sources and thereby environmental sustainability due to fossil fuel consumption. Therefore, aircraft engines being the significant emission source have attracted the attention of engineers toward improvement of the design process. In this study, turbojet engine (TE) and its components were examined with exergy, environmental, and sustainability metrics. Then, the effects of several design variables such as turbine inlet temperature (TIT) ranging between 850 K and 1100 K and compressor pressure ratio (CPR) ranging between 3 and 4 on exergetic and environmental parameters were investigated. As a novelty, a new index named specific irreversibility production (SIP) was improved. According to exergy assessment, the wasted exergy ratio (WExR) of the combustor was found as highest changing between 42.46% and 51.89%. Moreover, exergy efficiency of the turbojet engine was determined between 16.42% and 21.92%. According to environmental assessments, the ecological effect factor (EcoEF) of the TE was computed between 4.77 and 6.08 under ranges of different design variables. Finally, the SIP of turbojet was gauged between 0.488 MW/kN and 0.586 MW/kN. Considering these results, the TIT and CPR have high effect on the optimum engine performance and environmental parameters. [ABSTRACT FROM AUTHOR]

Aim: To investigate magnetic resonance image quality and the number of motion artifact-related repeated sequences based on anesthesia or sedation management during preoperative MR imaging for DBS surgery. Material and Methods: The medical records of patients who underwent DBS procedures at the hospital of Ondokuz Mayis University, between April 2011 and October 2021 were retrospectively analyzed. Age, gender, and diagnosis information were recorded for each case. Patients were grouped into general anesthesia, sedation, no sedation groups. The evaluation of magnetic resonance images was performed by a specialized in neuroradiology. The radiologist classified the image quality as good, moderate, or poor based on artifacts resulting from unwanted motion. Results: A total of 127 patients, out of 190 patients, were included in the study. There were no significant differences in image quality based on anesthesia/sedation method and airway management (p>0.05). No significant differences were observed in the number of repeated sequences when compared based on anesthesia/sedation method and airway management (p>0.05). Conclusion: General anesthesia, sedation, or no sedation during preoperative magnetic resonance imaging in patients with movement disorders did not result in significant differences in image quality and the number of sequences requiring repetition. [ABSTRACT FROM AUTHOR]

You The several series of PW4000 high bypass turbofan engine have used so far in many aircrafts. These commercial engines have played a crucial role on passenger and freight transportations. Namely, these engines are closely related to the environment impacts and security of energy supply. In this article, exergoeconomic analysis which is useful tool to investigate existing potential for improvement of the a system efficiency were carried out. The assesment, design and optimization of energy consuming systems are performed by means of these analyses. Therefore, thermo-economic costs were assigned to existing exergetic values of PW400 engine. Also exergo-economic performance parameters were evaluated. Finally, exergoeconomic deputy parameters were examined to understand relations with exergo-economic parameters. Based on the results of exergo-economics analysis, for Fan and exhaust, specific thrust costs are estimated 5.7051 $/hkN and 68.45$/hkN respectively. Also exergo-economics factor of PW4000 is found 7.958 % , while relative cost difference is determined at highest rate with 24.458 % for combustion chamber . With examination relations between economic variables and exergo-economic performance parameters, the change between 0.6 and 1.2 $/kg in the fuel price leads to increase the exhaust and fan specific thrust costs with 82.4701 $/hkN and 5.4332 $/hkN respectively. It is expected that conclusions of this study are helpful to notify exergo-economic impact of PW4000 engine Also, it may be benchmarking for similar gas turbine engines.

Background: Thrombocytopenia (platelet count below 150 x 103/μL) is a common finding after open-heart surgery and can lead to various complications, including patient death. This study aimed to determine the extent of non–heparin-induced thrombocytopenia in open-heart surgery and to highlight the associated factors. Materials and Methods: In this cohort study, 842 patients who underwent valve and/or coronary bypass surgery over a 5-year period were retrospectively analyzed. After open-heart surgery, patients whose platelet count was less than 150 x 103/μL on a complete blood count 12 and 24 h after surgery were classified as thrombocytopenic. Three hundred twenty patients without thrombocytopenia and 21 patients with a high probability of heparin-induced thrombocytopenia were excluded from the study. Logistic regression analysis was used to assess the association of independent variables in moderate-severe thrombocytopenia: Age groups, sex, underlying disease, symptoms, type of surgery, pump time, pulsatile or non-pulsatile duration, degree of hypothermia, hemodilution, oxygenator type, use of an intra-aortic balloon, and erythrocyte transfusion counts were included in the analysis. Results: A total of 501 patients were diagnosed as having non–heparin-induced thrombocytopenia, and 64.3% were male. Three hundred seventy-seven (75.2%) patients had mild thrombocytopenia and 124 (24.7%) had moderate-severe thrombocytopenia. The postoperative platelet count was significantly lower than the preoperative platelet count (213 x 103 vs.117 x 103/μL; p < 0.001). Moderate-severe thrombocytopenia was associated with age ≥80 years odds (OR = 9.026, 95% CI: [1.757–46.363]; p = 0.008), isolated valve surgery (OR = 3.090, 95% CI: [1.867–5.114]; p < 0.001), and valve surgery with coronary bypass (OR = 4.938, 95% CI: [1.638–14.889]; p = 0.005) compared to isolated coronary bypass, type of oxygenator (Nipro vital compared with Affinity OR = 11.097, 95% CI: [1.923–64.023]; p = 0.007), erythrocyte transfusion count (OR = 1.219, 95%CI: [1.046–1.420]; p = 0.011). Conclusion: Age 80 years or older, surgical procedures including heart-valve surgery, and the number of red blood cell transfusions are associated with the risk of moderate-to-severe thrombocytopenia. This study provides a guide in terms of risk factors that may lead to moderate-to-severe thrombocytopenia after open-heart surgery. However, future multicentre prospective randomized studies may provide more detailed information on this subject. [ABSTRACT FROM AUTHOR]

The limited energy source indicates the necessity of efficient energy consumption in every field of life. Especially, the prompt growth in aviation sector makes this issue more important. In this study, effects of power settings on several thermodynamic indicators regarding low by-pass turbofan engine (LBP-TFE) are investigated. For this aim, the energy and exergy analyses are implemented to the system of turbofan engine for eighteen operating points. According to performance analysis, thrust value of the LBP-TFE changes from 10.77 kN to 71.8 kN throughout RPM values. According to exergetic findings, relative exergy losses from Fan outlet decreases from 52.34 % to 30.58 % whereas exergy efficiency of the LBP-TFE increases from 10.9 % to 30.1 %. Considering improved exergy efficiency, it changes 25.03 % and 41.03 % at the same RPM intervals. As for environmental assessments, environmental effect factor (EEF) of LBP-TFE diminishes from 5.8 to 1.32 while ecological effect factor decreases from 9.16 to 3.31. Finally, specific irreversibility production of LBP-TFE decreases from 0.4811 MW/kN and 0.2716 MW/kN. Considering these outcomes, behaviour of the investigated metrics regarding main components is different from each other. Therefore, the results of these parameters calculated for the whole engine could help understanding optimum running point in terms of exergetic and environmental sustainability. [ABSTRACT FROM AUTHOR]