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In this study, effects of high-pressure compressor pressure ratio (HPC PR) and bypass ratio (BPR) regarding adaptive cycle turbofan (ACT) engine on performance parameters and second law parameters of thermodynamics involving Carnot, Curzon–Ahlborn, Caputo, thermal and exergy efficiencies are dealt with. For this aim, HPC PR changes between 4 and 6, and bypass ratio ranges between 0.3 and 0.6. At same altitude of 10,000 m, comparative analysis is performed for efficiency behavior of ACT engine at military mode (MM) and afterburner mode (ABM). Better understanding of performance improvements of a military aircraft can be possible by investigating these efficencies for different design variables. Based on these computations, environmental and irreversibility parameters involving specific irreversibility production and environmental effect factor regarding ACT engine are dealt with at both modes. According to performance outcomes, SFC of the ACT engine decreases by 7.66% at MM, whereas it increases by 0.34% at ABM due to higher BPR. Moreover, it diminishes by 4.98% at MM and decreases by 0.42% at ABM with influence of the elevated HPC PR. As for efficiency analyses, exergy efficiency of ACT engine increases from 20.04 to 21.7% at MM, whereas it decreases 17.43 to 17.37% at ABM with effect of raised BPR. The higher HPC PR leads to increase from 20.32 to 21.38% at MM and from 17.39 to 17.46% at ABM. Among the components, the combustor has the lowest exergy efficiency, which is favorably affected from both variables at MM. Finally, environmental effect factor of the ACT becomes lower thanks to the higher BPR and HPC PR at MM. However, at ABM, to increase these variables do not result in lower EEF. Therefore, considering design parameters according to operation modes could lead in finding more meaningful outcomes. It is thought that this study helps in analyzing of thermodynamic parameters with respect to different design parameters.

Aviation emissions originated from the fuel burn have been hot topics by engineers and policy-makers due to their harmful effects on the environment and thereby human health as well as sustainability. In this study, it is tried that several emission indexes (EIs) involving CO, HC and NOx as well as fuel flow of several commercial aircraft engines (CAEs) are predicted using support vector regression (SVR) and long short-term memory (LSTM) approaches for take-off phase. Moreover, exergo-environmental parameters involving exergy efficiency (ExEFF), wasted exergy ratio (WExR) and environmental effect factor (EEF) pertinent to CAEs are computed employing thermodynamics laws. While establishing the models, rated thrust, by-pass ratio, overall pressure ratio and combustion type of the CAEs are utilized as the model inputs. According to the findings of emission modelling, the coefficient of determination (R

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.

In this study, thermodynamic analysis of PW4000 engine used in long-haul aircraft was carried out for eight flight phases. For this aim, energy, exergy, and exergo-sustainability metrics regarding ...

Aircraft must have reliable and sustainable sources of power systems and must use energy efficiently. Aircraft engine advances have dramatically improved aircraft fuel efficiency. Variable cycle engine (VCE) has been promising in both civil and military areas in the last decades. An important challenge for energy saving regarding the engine is to find optimum flight conditions. For this aim, this study investigated energetic and exergetic off-design performance modeling of the variable cycle turbofan engine with respect to flight conditions and potentially energy benefits for a new-generation combat aircraft. Current analysis mainly focused on how to simplify off-design performance model of the VCE in terms of thrust, specific fuel consumption (SFC), overall and exergy efficiencies with the aid of enhanced least-squares estimation-based genetic algorithm (LSEGA) in flight phases. According to analyses, the results show that the proposed method is capable of modeling all the thermodynamic off-design parameters with root mean square error values of as low as 0.000162 for exergy efficiency, 0.000311 for overall efficiency, 1.007 for thrust and 0.0763 for SFC. It is observed from the study that the proposed LSEGA algorithm has successfully converged into optimal solutions for all indexes and flight regimes and all the off-design performance models of the VCE energetic indexes are obtained with high accuracy.

Purpose Usage of gas turbine engines has increased by day due to rising demand for military and civil applications. This case results in investigating diverse topics related to energy efficiency and irreversibility of these systems. The purpose of this paper is to perform a detailed entropy assessment of turbojet engines for different flight conditions. Design/methodology/approach In this study, for small turbojet engines used in unmanned aerial vehicles, parametric cycle analysis is carried out at (sea level-zero Mach (hereinafter phase-I)) and (altitude of 9,000 m- Mach of 0.7 (hereinafter phase-II)). Based on this analysis, variation of performance and thermodynamic parameters with respect to change in isentropic efficiency of the compressor (CIE) and turbine (TIE) is examined at both phases. In this context, the examined ranges for CIE is between 0.78 and 0.88 whereas TIE is between 0.85 and 0.95. Findings Increasing isentropic efficiency decreases entropy production of the small turbojet engine. Moreover, the highest entropy production occurs in the combustor in the comparison of other components. Namely, it decreases from 2.81 to 2.69 kW/K at phase-I and decreases from 1.44 to 1.39 kW/K at phase-II owing to rising CIE. Practical implications It is thought that this study helps in understanding the relationship between entropy production and the efficiency of components. Namely, the approach used in the current analysis could help decision-makers or designers to determine the optimum value of design variables. Originality/value Due to rising isentropic efficiencies of both components, it is observed that specific fuel consumption (SFC) decreases whereas specific thrust (ST) increases. Also, the isentropic efficiency of a compressor affects relatively SFC and ST higher than that of the turbine.

Indexed keywords SciVal Topics Metrics Abstract Application fields of small turbojet engines (STJE) have been increasing day by day due to their superior features such as high power to weight ratio and reliability. In this study, parametric cycle analysis peculiar to STJE is implemented for different design variables such as compressor pressure ratio (CPR), turbine inlet temperature (TIT) as well as ambient temperature (T0). Based on these evaluations, several performance metrics of STJE are dealt with together by applying three different methods such as multi-objective genetic algorithm (MOGA), particle swarm optimization (MOPSO) and grey wolf optimization (MOGWO) under five analyses. According to performance analyses, net thrust of the STJE has improvement from 3.2 kN to 5.41 kN due to the increased TIT whereas it deteriorates from 4.87 kN to 4.67 kN due to the elevated CPR. However, with effect of the higher TIT, specific fuel consumption (SFC) of the STJE ascends from 42.96 g/kNs to 49.04 g/kNs while it diminishes from 39.57 g/kNs to 31.5 g/kNs owing to the higher CPR. The higher T0 leads net thrust to lower but the higher SFC. According to optimization findings at fourth analysis, the lower SFC is obtained with 31.51 g/kNs by MOGA than the other methods where SFC is 33.11 g/kNs whereas the higher net thrust is obtained with 6.209 kN by both MOPSO and MOGWO than the findings of MOGA where net thrust is 4.68 kN. When considering five optimization analyses, the findings of MOGA, MOGWO and MOPSO could be utilized depending on aircraft mission that turbojet engine requires to perform. It is thought that performing of multi-objective optimization could help in designing turbojet engines to the engineers.

Assessment of performance of turbofan engine with different design parameters is crucial for meeting the performance requirements by considering each key components of the engine. To comprehend influences of component efficiencies to mitigate environmental effect from turbofans has been hot topics in aviation field recently. In this study, firstly, impacts of polytropic efficiencies of fan, compressor and turbine as well as pressure ratio of combustor (CPR) on several turbofan performance are dealt with at several flight conditions. Secondly, it is tried to show difference of performance metrics under ideal and real conditions. The discrepancy between performance parameters computed at ideal and real cases gets relatively high. Namely, at take-off condition, the difference between ideal and real specific fuel consumption is computed as 29.12% whereas it is found as 28.37% at cruise condition, which shows that considering the system as ideal makes the computations inappropriate for performance analysis. Moreover, performance parameters of turbofan is more sensitive to compressor efficiency compared with turbine. As the polytropic efficiencies of fan and compressor are close to highest, net thrust of the engine develops from 109.05 kN (baseline) to 124.71 kN at take-off while it increases from 26.36 kN (baseline) to 29.27 kN at cruise condition. With effect of the elevated pressure ratio of combustor and efficiency of turbine, thrust of the engine increases to 118.23 kN at take off and to 27.84 kN at cruise condition. Finally, as Mach number increases, the difference between ideal and real performance values sharply increases. Therefore, when analyzing on turbofan engines, the assumptions should be minimum as possible as, otherwise the findings make the engineers to misguide for system optimization. Besides, these outcomes show that if the components with higher polytropic efficiency can be obtained, overall efficiency of turbofan, thereby environmental sustainability could be elevated to upper level compared with baseline.

Turboprop engines have been commonly adopted for several applications such as unmanned aerial vehicle and commuter aircraft. In this study, the effects of propeller efficiency (PEF) with various compressor pressure ratio (CPR) are examined for energetic, exergetic, environmental and sustainability indicators of a small turboprop engine (S-TPE) at sea level. For this aim, PEF of the S-TPE has the range varying between 0.7 and 0.95 whereas its CPR has boundary changing between 10 and 12.5. According to performance results, thrust of the S-TPE changes from 5.11 kN to 6.88 kN due to rising PEF and from diminishes from 5.9 kN to 5.68 kN due to rising CPR whereas overall efficiency of the S-TPE alters from 22.1% to 29.7% owing to the PEF effect and from 24.7% to 25.5% owing to the CPR effect. On the other hand, exergetic parameters of the components of the engine remain constant with the PEF effect whereas both effects (PEF and CPR) are observed on exergetic metrics of the whole engine. In this context, exergy efficiency of the combustor increases from 84.83% to 86.7% due to only the CPR effect. Moreover, exergy efficiency of the S-TPE experiences the increase from 21.39% to 28.77% due to rising PEF while it raises from 23.99% to 24.71% due to rising CPR. Finally, specific wasted exergy of the S-TPE decreases from 0.7566 MW/kN to 0.5624 MW/kN with the effect of PEF whereas it drops from 0.6751 MW/kN to 0.6540 MW/kN with the effect of CPR. These findings show that a small change in design variables reflects on energetic and exergetic performance of the engine at different degrees.(c) 2022 Elsevier Ltd. All rights reserved.

Studying efficiency and emissions of an aircraft engine at cruise phase is of high importance so as to help in finding optimum flight conditions. Especially, since exhaust emissions from the engine lead to climate change, quantifying exhaust emissions could show adverse effect of the aero-engine on environment. In this study, en- ergetic and exergetic behaviour of high by-pass turbofan are parametrically examined. Besides, cruise NOx emission is measured by P3-T3, Boeing Fuel Flow Method 2 (BFFM2) and DLR methods. Moreover, the index as Specific NOx Production (SNP) is quantified for the turbofan engine. Thanks to this parameter, NOx effect of the engine is compared according to different flight conditions. For this aim, parametric cycle equations and emission calculation methods regarding turbofan engine are encoded so as to determine performance outputs for Mach changing from 0.7 to 0.9 and altitude between 9000 m and 11,000 m. According to performance results, the average specific fuel consumption (SFC) regarding turbofan engine is predicted as 19.65 g/kN.s at 9 km and 19.68 g/kN.s at 11 km. As for exergo-sustainability index, environmental effect factor is calculated as 1.19 at 9 km and 1.26 at 11 km. Also, the average cruise NOx emission index is found as 16.66 g/kg at 9 km and 13.93 g/ kg at 11 km. Finally, the mean SNP regarding the turbofan is measured as 0.5071 g/kN.s at 9 km and 0.3374 g/ kN.s at 11 km. The findings of this study provide useful insights to comprehend effects of flight conditions on aircraft emissions. In terms of environmental sustainability, decision mechanism could be enhanced to find out optimum flight conditions thanks to the presented results.

Examining the effects of design variables on performance and emission parameters for gas turbine engines is of high importance. In this study, the effects of by-pass ratio (BPR) and turbine inlet temperature (TIT) of turbofan engine on energy, exergy, and exhaust emissions are parametrically analyzed at 0.85 Ma and altitude of 11 km. Moreover, cruise NOx emission is quantified by Boeing Fuel Flow Method 2 (BFFM2) and DLR methods. As a novelty, specific NOx production (SNP) is first quantified for PW4000 engine. In this study, parametric cycle equations regarding turbofan engine are encoded so as to compute performance and emission metrics. According to energy analysis, specific fuel consumption (SFC) of the turbofan averagely changed from 19.82 to 18.64 g/kNs due to rising BPR whereas it increases from 18.62 to 19.93 g/kNs owing to rising TIT. Furthermore, exergy efficiency of turbofan rises from 27.67% to 29.42% due to rising BPR whereas it decreases from 29.46% to 27.65% owing to rising TIT. As for NOx emission results, the higher BPR leads to the lowering of the SNP index of the turbofan from 0.46 to 0.375 g/kNs while the higher TIT yields to the increase of the SNP index from 0.377 to 0.455 g/kNs. According to the findings of this study, the decision mechanism could be improved to find out optimum design variables in terms of eco-friendly aircraft activities.

Main idea of power scheduling for aero-engines is to decompose the complex nonlinear energy management and is to cover each break point in all operating conditions by digital engine control unit. In the current study, dynamic energetic and performance measures of an experimental small target drone turbojet engine are calculated at various shaft speeds in test-cell. In this context, some experiment test steps were conducted to measure the performance parameters of the engine at different shaft speeds. With the help of the calculated parameters, efficiencies, power and energy indexes of the engine are also determined. According to analysis, wasted power varies between 7.69 kW and 259.61 kW, while total power of the fluid is 10.2 kW at 25000 RPM and reaches 331.66 kW at 47500 RPM. As for engine efficiency results, with increasing RPM, thermal efficiency is strongly varying with 18.33%, whereas the change ratio of propulsive efficiency stays modest level with 5.17%. As a conclusion, it is expected that these assessments can be employed in the control law design of similar power system controller and also to increase the efficiency of existing systems.

This study focuses on for a PW4000 high-bypass turbofan engine using energy, exergo-sustainable and performance viewpoint. For this aim, irreversibility and performance analyses are firstly performed for five main engine components at ≈260 kN maximum take-off thrust force. Besides, overall efficiency of the turbofan is determined to be 33 %, while propulsive and thermal efficiency of the turbofan are 72 % and 46 % respectively at 0.8 M and 288.15 K flight conditions. Secondly, calculation component-based exergetic assessment is carried out using exergetic indicators. According to the calculation, the exergetic efficiency of the engine is 32 %, while its waste exergy ratio is 0.678. Furthermore, exergetic sustainability measure is obtained as 0.473, while enviromental effect factor is 2.112. These indicators are also anticipated to help comprehend the connection between engine performance parameters and worldwide dimensions such as environmental effect and sustainable growth.

BACKGROUND Quadratus lumborum blocks (QLBs) are relatively novel regional anaesthesia techniques, and the efficacy of all three types of QLB for postoperative analgesia in caesarean delivery (CD) has been demonstrated in separate studies. The aim of the present study is to compare the analgesic efficacy of the QLB-II and QLB-III blocks performed at the end of surgery in patients undergoing spinal anaesthesia for CD. METHODS We conducted a comparative, blinded, prospective, randomised and efficiency study. A total of 80 patients scheduled for elective CD under spinal anaesthesia were randomly allocated to receive either bilateral ultrasound-guided QLB-II or QLB-III block in a 1:1 ratio. The primary outcome was opioid consumption administered by a patient-controlled analgesia in the first 24 hours postoperatively. The secondary outcome of the study was pain intensity. Also, the time of first opioid requirement and the presence of nausea and vomiting were recorded. RESULTS Morphine consumption was statistically significantly lower in the QLB-III group when compared with the QLB-II group at the 3rd, 6th, 12th and 24th hours (P

Background Erector spinae plane block (ESPB) is a recently described block. In many reports, ESPB has been reported to provide effective postoperative analgesia in patients undergoing cesarean delivery (CD). Herein, we compared the effectiveness of ESPB and control group in postoperative analgesia in patients undergoing CD under spinal anesthesia. Methods This assessor blinded, prospective, randomized, efficiency study was conducted in the postoperative recovery room and ward at a tertiary university hospital. Eighty-six patients (ASA II–III) were recruited. Following exclusion, 80 patients were randomized into two equal groups (block and control group). Standard multimodal analgesia was performed in the control group while ESPB block was performed in the intervention (ESPB) group. Opioid consumption was measured and pain intensity between groups was compared using Numeric Rating Scores (NRS). Results NRS was lower in Group ESPB at 3rd and 6th hours. There was no difference between NRS scores at other hours. Opioid consumption was lower in Group ESPB. Conclusion When added to multimodal analgesia, bilateral ultrasound guided low thoracic ESPB leads to improve the quality of analgesia in the first 24 hours in patients undergoing CD.

In the current study, advanced exergo-dynamic analysis of a micro-turbo jet (μ-jet) along with conventional exergy analysis is presented in various running shaft speed modes. In this context, major advanced exergetic indicators of μ-jet components are evaluated at the various running testing. The operation modes were represented as operation shaft speeds between 48,850 and 77,000 RPM (revolution per minute), while μ-jet produced within the range of 45.01–121.27 N thrust force in these modes. Improvement potentials of turbomachinery components and exergy destruction rates are calculated throughout the real-time testing modes. According to the analysis, the combustor has the lowest exergy efficiency ranging from 41.06% to 50.18%. Also, the study shows that the exergy efficiency values of the experimental μ-jet are found to be as 6.56% at Mode-1, 10.12% at Mode-2, 15.46% at Mode-3 and 17.02% at Mode-4, respectively. Other important findings for μ-jet are that unavoidable exergy destruction rate varies between 94.89% and 95.79%, while endogenous exergy destruction value changes between 89.79% and 91.47% in these modes. Thanks to the present analysis, the methods decreasing avoidable exergy destruction that changes between 4.21% and 5.11% could be focused.

The goal of this study was to determine if the neutrophil-lymphocyte ratio (NLR) predicts mortality in patients hospitalized in the intensive care unit (ICU) with an ischemic stroke. Between January 1 and December 31, 2021, 116 patients admitted to our emergency department with the diagnosis of ischemic stroke and hospitalized in the 3rd level ICU unit were included in the study and divided into two groups: patients who died (Group 1: n=62) and patients who survived (Group 2: n=54). Patients’ age, gender, presence of chronic diseases, Acute Physiology and Chronic Health Evaluation (APACHE) II score, and neutrophil count, lymphocyte count, and NLR were obtained by dividing these two numbers in the first complete blood count taken at the time of admission to the emergency department were collected and analyzed. While 54 (46.5%) patients were discharged from the ICU, 62 (53.4%) patients died. 60 (51.7%) of the patients were female. The average age of patients was 76.85±10.70. APACHE II score was found to be correlated with mortality (AUC 0.70, 95% CI (0.616-0.802) (p=0.01). When the APACHE II cut-off value was more than 13.5, it predicted mortality with 95% sensitivity and 85% specificity. The median NLR ratio of the patients was found to be 5.08 (0.38-35.16) in the survivors and 11.68 (1.38-113.00) in patients that died. NLR was lower in survivors (p=0.002). NLR may be a valuable marker in predicting mortality in stroke patients admitted to the ICU.

As sustainability, increasing of fuel and energy efficiency has become a greater concern in aircraft design and fleet operation for two decades. To meet this need, a new methodology is being developed here that proposes the use of optimization for indexing the sustainability throughout flight phases of the aircraft and its power system. In this study, off-design modeling of several exergetic parameters for the turbofan engine is conducted by using genetic algorithm at cruise phase. In this context, exergetic sustainability parameters such as exergy efficiency, wasted exergy ratio, exergy destruction factor, environmental effect factor and exergetic sustainability index are calculated for the aircraft engine. After this process, linear modeling of exergetic indexes, depending on Mach (0.7–0.9) and altitude (9–11 km) ranges is performed. The results highlight that the linear modeling of exergetic parameters with the genetic algorithm (GA) enhances accuracy of the model compared to the least square method (LSM). Modeling of exergy efficiency for the turbofan is achieved with R = 0.9974 by LSM whereas it is obtained with R = 0.9999 by GA at altitude of 11 km. Finally, modeling of exergetic metrics for turbofan engine by using parametric flight data could enable so as to determine optimum cruise flight conditions in terms of both engine performance and environmental sustainability.

In the present study, the exergetic performance behaviours of a variable cycle engine (VCE) which is considered as an alternative engine for the fighter aircraft were analysed for eight flight phases excluding critical fighter phases. In this context, performance analysis of the variable cycle engine model was parametrically performed by on-design relations of an afterburner turbofan. These results were compared with those of conventional military turbofan (CMT) engine. Next, exergetic parameters per-taining to the VCE were measured on component-basis for eight flight phases. Moreover, five exergetic sustainability indexes of the VCE model at all flight phases were investigated in order to observe effects of flight phases on these metrics and these outcomes were compared with the conventional one. Ac-cording to comparative performance analysis, SFC value of the VCE for cruise phase was estimated as 23.89 g/kN.s whereas that of the CMT engine was computed as 27.25 g/kN.s. On the other hand, the component-based results illustrate that exergy efficiency of the combustor of the VCE has relatively low values ranging from 83.65% to 89.06%, whereas those of high pressure and low pressure turbines have relatively high ratio at concerned flight points. Furthermore, the whole engine-based results show that exergy efficiency of VCE is approximately varies between 7.45% and 31.39% whereas that of the CMT engine changes between 6.31% and 21.5% throughout flight phases. Finally, exergetic sustainability index was calculated the highest at subsonic cruise phases. Namely, it is estimated between 0.45 and 0.6 for the VCE and between 0.31 and 0.34 at these phases for the CMT engine. It is thought that studying exergetic parameters for a military aircraft during the important flight phases could help in understanding which flight segment is useful in terms of sustainability. (c) 2021 Elsevier Ltd. All rights reserved.

In this study, environmental and enviroeconomic analyses regarding two different turbofan engine families that are commonly used in commercial aircrafts are carried out at Landing and Take-Off (LTO) cycle involving take-off, climb-out, approach and idle phases. For this aim, HC, CO, NOX and CO2 emissions of family 1 (F1) and family 2 (F2) engines are taken into consideration over the course of LTO cycle based on International Civil Aviation Organization (ICAO) emission database. The average thrust values of these engines are 115.12 kN for F1 engines and 123.77 kN for F2 engines. Global Warming Potential (GWP) and enviroeconomic cost factor (ECF) for the each engine are calculated. Also, to predict GWP and ECF parameters, these metrics are modelled based on by-pass ratio and overall pressure ratio. According to the results of the study, the average GWP value of F1 and F2 engines are obtained as 2256.17 kg_CO2/day_cycle and 1779.02 kg_CO2/day_cycle, respectively. On the other hand, the average enviroeconomic cost factor (ECF) of F1 and F2 engines are computed as 261.71 Euro/day_cycle and 206.36 Euro/day_cycle, respectively. Finally, accuracy of GWP model is achieved with R2 = 0.9956 for F1 engines and R2 = 0.9664 for F2 engines. The relatively low R2 of the model for F2 engines could be attributed to effects of different types of the combustor. It is seemed that the present analysis allows to predict the average environmental effect and economic cost of the aircraft engines in service.

Study objective Erector Spinae Plane Block (ESPB) is a recently described block. Both ESPB and Quadratus Lumborum block type II (QLB-II) have been reported to provide effective postoperative analgesia in patients undergoing laparoscopic cholecystectomy (LC). In this study, we compared the postoperative analgesic effects of ESPB and QLB-II in patients undergoing LC. Design Assessor Blinded, prospective, randomized, controlled study. Setting Tertiary hospital, postoperative recovery room & ward. Patients 80 patients (ASA I-II) were recruited. Patients were allocated in to two equal groups (ESB and QLB-II). All patients were included in analysis. Interventions Standard multimodal analgesia was performed in all groups. ESPB and QLB-II were performed under ultrasound guidance. Measurements Mean opioid consumptions and Numeric Rating Scores was measured during the first 24 postoperative hours. Main results Demographic data was similar between groups. There was no difference between NRS scores and opioid consumption at any hour between the groups. Conclusion While ESPB and QLB-II are not significantly different, they improve analgesia quality in patients undergoing LC.

The dry leaf technique for erector spinae plane block in supine position: An alternative to lateral decubitus or prone position

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.

Nowadays, small-size turbojet engines play a significant role on various military and civil missions. In this study, exergoeconomic analysis of TRS-18 turbojet engine was conducted for nine flight phases. First aim is to find out differences between exergoeconomic behaviour of the components originated from their both irreversibility and purchase costs. The second objective is to reveal effects of flight phases on exergoeconomic performance of TRS-18 and its components by employing several exergoeconomic indicators regarding the TRS18. These indicators are exergy destruction cost, relative cost difference, exergoeconomic factor and specific thrust cost. To estimate cost-ineffective components of TRS-18 engine, component-based exergoeconomic assessment was carried out for each mission. Based on results of exergoeconomic analysis for the whole TRS-18 engine, specific thrust cost of the TRS-18 was found at relatively high values ranging 398.2 and 422.04 $/h.kN at loiter III and IV phases where the engine operates at partial power whereas taxi-out, take-off and landing (TTL) phases have the relatively low specific thrust cost values ranging 159.53 and 166 $/h.kN. Moreover, exergoeconomic factor of the whole TRS-18 was found as relatively low values with approximately 21% at TTL phases. Considering component-based results, the lowest exergoeconomic factor, ranging from 25% to 40%, belongs to combustor, whereas gas turbine has relatively high exergoeconomic factor, varying from 89% to 92%. Finally, for the combustor, exergy destruction cost was determined at the relatively highest rates for whole flight phases. It changes between 35.74 $/h at loiter-II phase and 69.79 $/h at take-off. It is thought this study can help in finding cost-effective flight phases by means of comprehending the nature of the relationship between flight phases and the corresponding exergoeconomic parameters. Also, off-design exergo-economy obtained with this paper may be applied to the other gas turbine engines.

Energy security and low environmental impact issues become hot topics due to usage of small-sized turbojet engines in many areas. In this study, thermodynamic analysis of target drone turbojet engine (TRS18) was experimentally carried out for different non-linear loads. The main goal is to reveal effects of power settings on exergetic performance of TRS18 and its components by using energy, exergy and exergo-sustainability metrics regarding the TRS18 for each load. For this aim, several input parameters related to TRS18 were measured while some of them were calculated by reverse engineering. Based on these data, energetic and exergetic computations for three components and whole engine were performed with respect to ten RPM values. According to component-based exergy results, exergy destruction of components increase due to rising RPM value. Namely, for the combustor, exergy destruction ranges from 214.46 kW to 722.54 kW whereas it changes between 12.36 kW and 98.57 kW at turbine. As for compressor, it is observed between 4.19 kW and 37.23 kW. However, increasing of RPM value affects favourably exergy efficiency of components. Namely, exergy efficiency of the combustor changes between 41.8% and 63.4% whereas that of the turbine increases from 91.9% to 96.1%. For compressor, it is observed between 83.6% and 89% through rising power settings. With respect to exergetic findings of the whole TRS18 engine, exergy efficiency of TRS18 increases 5.8%–18.07% whereas exergetic sustainability index of the engine is calculated from 0.061 to 0.22 through rising RPM values. However, exergy destruction factor of TRS18 decreases from 67.9% to 49.6% while environmental effect factor regarding the engine diminishes from 16.23 to 4.53. For thermal systems which be exposed different loads, this study could establish relationship between engine efficiency and operation load. Moreover, it could be inferred that examining sustainability aspects of TRS18 under different loads helps finding optimum operating ranges in terms of fuel consumption and environmental impact.

Behçet’s disease (BD) is a chronic inflammatory disease with multisystem involvement, first described by Hulusi Behçet in 1937. Recurrent mouth and genital area ulcers, skin findings and uveitis are characteristic features. BD is most commonly seen in the Far East, the Middle East and Mediterranean countries in all ethnic groups, and the frequency in our country has been reported to be 110-420/100.000. Since BD is a multisystemic disease, anesthetic drug administration and management are challenging in patients with BD. We aimed to present a 26-year-old pregnant patient with BD undergoing cesarean section with spinal anesthesia and evaluate the anesthetic techniques in the light of the current literature.

The one of ways to moderat aviation emissions resulting from aircraft engines is to comprehend formation mechanism of environmental impacts. In this article, exergo-environmental aspects of Boeing-747 propulsion system (PW4000 turbofan) used in long range air transport is dealt with life cycle assesment method for eight different flight phases. Environmental impact regarding the turbofan engine and its components is calculated using Eco-indicator points per unit second (Pts/s). Results show that environmental impact related to exergy destruction for the combustor changes from 8.16 mPts/s (at cruise phase) to 24.35 mPts/s at (take-off phase), whereas its environmental impact related to component production and maintenance phases is found as 0.374 mPts/s. On the other hand, exergo-environmental factor of the whole PW4000 engine is calculated as the lowest with 15.83% and 17.22% at take off and climb-out phases, respectively. Moreover, a new environmental indicator, namely, specific thrust environmental effect index (mPts/kN.s) is defined in this study. In this context, environmental effect index of Fan and core specific thrust is estimated the lowest with 0.065 mPts/kN.s and 0.107 mPts/kN.s at cruise phase, respectively. Especially, take-off and climb out phases seem to be the two where the PW4000 behaviour affects environmental effect to the greatest degree. The reason for this could be attributed that these two phases have relatively higher thrust settings. However, considering cumulative environmental impact, cruise phase has the highest environmental impact from exhaust air of the Fan and core as 54.2 Pts and 74.41 Pts, respectively. Consequently, it is expected that the method used in present study could help comparing aircraft flight phases in terms of exergo based-environmental impact.

ekmekci, ismail/0000-0002-2247-2549; WOS: 000570077700012 For next generation aircraft, Adaptive Cycle Engine (ACE) is a candidate to fulfill the multi-mission requirements of flight. This new concept is promising to complete deficiencies of conventional low by-pass mixed turbofan engines because the ACE model incorporates different thermodynamic cycles (turbojet and turbofan) on the same air vehicle system. Firstly, performance and design results of the ACE model are compared with those of fixed cycle low by-pass turbofan engine by using specific fuel consumption (SFC), specific thrust (ST), power and efficiency parameters. Moreover, verification of the newly developed ACE model is performed. Secondly, considering some design parameters, ST and SFC values of the ACE model are analyzed for double by-pass mode (DBM) and single by-pass mode (SBM). Considering performance analysis of the ACE, SFC value is determined as 17.85 g/kN.s at DBM and 42.18 g/kN.s at SBM. According to results of energy analysis, overall efficiency of the ACE is calculated as 23% for DBM and 9% for SBM whereas fixed cycle engine has 18% for military mode and 7% for afterburner mode. Finally, minimization of (SFC) is obtained with genetic algorithm approach. Based on the design variables such as by-pass ratio and turbine inlet temperature, minimum SFC value for the ACE model is calculated as 17.41 g/kN.s at DBM and 40.45 g/kN.s at SBM. (C) 2020 Elsevier Ltd. All rights reserved. Eskisehir Tehnical University in Turkey; Eskisehir Tehnical University Scientific Research Projects Commission [20DRP056] Authors would like to thanks Eskisehir Tehnical University in Turkey for financial and technical support. This study was supported by Eskisehir Tehnical University Scientific Research Projects Commission under the grant no: 20DRP056.

The several series of PW4000 high bypass turbofan engine have used so far in many aircrafts. These commercial engines are closely related to environmental impacts and security of energy supply. In this study, exergo-economic analysis which is useful tool to investigate existing potential for cost-effective components was carried out. Therefore, exergo-economic indicators of PW4000 engine was examined by employing energetic, exergetic and economic relations at non-linear different power settings. Moreover, exergo-economic performance of PW4000 and its components was explored with several parameters such as exergy destruction cost ($/h), exergo-economic factor (%) and specific thrust cost ($/hkN). Based on the results of exergo-economic analysis, a specific cost of Fan thrust was found about 3 times lower than Exhaust thrust at maximum revolution per minute (RPM). Namely, specific thrust costs of Fan and Exhaust were estimated 14.47 $/hkN and 54.78 $/hkN respectively. Considering the lowest and highest power settings, exergo-economic factor of the PW4000 engine was found as 17.28% and 10.59%, respectively. On component basis, the highest exergo-economic factor, ranging from 57.42% to 86.32%, was observed at Low Pressure Compressor (LPC) unit. Finally, exergy destruction cost, varying from 655 $/h to 1688 $/h, was found the highest at Combustor throughout RPM values. This study can help in understanding the nature of the relationship between non-linear power settings and the relevant exergo-economic parameters.

For next generation aircraft, Variable Cycle Engine (VCE) is a candidate to fulfil the multi-mission requirements of flight. This new concept is promising to complete deficiencies of conventional low by-pass mixed turbofan engines because the VCE model incorporates different thermodynamic cycles (turbojet and turbofan) on the same system. Namely, having single by-pass (SBM) and double by-pass modes (DBM), these engines can modulate by-pass ratio, ranging from 0.3 to 1.8 during flight with respect to operating condition requirements. In this study, parametric equations for components of the developed VCE model are determined by means of cycle equations of a mixed-flow turbofan with afterburner. The first aim is to compare energetic performance results of the developed VCE with the results of F100-PW-100 (as called F100) used on F-15 or F-16 for SBM and DBM. Secondly, the main goal of this study is to perform second law analysis for the VCE model and compare it with the results of the F100 engine for off-design, at which flight altitude (9–20 km) and Mach number (0.3–1.9) changes. For this aim, thermodynamic data (pressure, temperature, mass flow etc.) of this engine main components are obtained from GasTurb program for above stated flight conditions. On the other hand, exergy analysis along with five sustainability parameters is carried out at SBM and DBM as comparing with those of F100 engine. Off-design analysis shows that the specific fuel consumption (SFC) varies from 19.97 g/kN.s to 28.25 g/kN.s for VCE and from 23.91 g/kN.s to 31.14 g/kN.s for F100 at DBM. Moreover, at SBM, SFC changes from 52.68 g/kN.s to 59.19 g/kN.s for VCE and from 58.04 g/kN.s to 63.57 g/kN.s for F100 throughout the entire flight conditions. As for exergy-based sustainability analysis, exergetic sustainability index (ESI) of the whole VCE is found to be in the range of 0.14 and 0.51 for DBM and to be in the range of 0.26 and 0.38 for SBM. For F100 engine, ESI is calculated to be in the range of 0.10 and 0.39 for DBM and to be in the range of 0.15 and 0.34 for SBM. It is thought that this study can help in understanding the effect of the working cycle on engine performance and sustainability parameters.

Toksik ajanın kimyasal etkileri sonucuorganizmada oluşturduğu fonksiyonel bozukluk ya da yapısal hasara zehirlenmedenir. Gebelerde bildirilen toksik maruziyetin çoğu kaza ile olmaktadır.Gebelik sırasında meydana gelen fiziksel ve fizyolojik değişikliklerintoksikolojik etkileri arttırıcı veya azaltıcı payı olmaktadır.Bor (B) atom numarası 5 olan yarıiletken özelliklere sahip ve canlı beslenmesinde mikro besin elementidir.Metal-bor oksijen bileşiklerine genel olarak “borat” denir. Borat ile hafif zehirlenmede bulantı,kusma, karın ağrısı ve ishal ciddi zehirlenmelerde renal fonksiyon bozukluğu,kardiyak aritmi, asidoz, letarji ve hipotansiyon görülebilir. Bu olgu sunumunda 24 haftalık gebede oralyolla kazara alınan boraks (sodyum borat) zehirlenmesini sunmak istedik., Functional impairment or thestructural damage in the organism caused by the chemical effect of the toxicagent is called poisoning. Many toxic exposures reported during pregnancies arecaused by accidents. Physical and physiological changes that occur duringpregnancy have increasing or decreasing impact on toxicological effects. Bor(B) with atomic number 5 is a micronutrient element with semi-conductive properties. Metal-bor oxygen compoundsare generally referred as ‘borate’. Mild borate poisoning may lead to nausea,vomiting,whereas in severe poisoning cardiac arrythmia, acidosis, lethargy andhypotension can be detected.In this case report, we aimed to present accidental oral borax (sodiumborate) poisoning by 24 weeks of gestation.