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The purpose of this paper is to present a novel turbine balancing using Ant Colony Optimization method. Results are compared against well known optimization methods available at open literature. With the new approach, turbine blade set can be separated in to two blade sets as heavy and light blades. This approach makes possible the application of Ant Colony Optimization methodology. ACO methodology is compared with Steepest Descent and Exchange Heuristic methods using nine different initial blade placements. And results are presented. Performance of the three evaluated methods is affected by the initial blade placement. Exchange Heuristics method was quick and provided good results in most of the cases. Ant colony optimization was able find better results than the Steepest Descent method. The approach of separating blades into two sets decreased the solution time of Steepest Descent algorithm. Ant colony optimization method can be used for turbine blade assembly and balancing for aircraft gas turbine applications. This approach is used for the first time in this area and not seen at the open literature.

Exergy efficiencies of the gas turbine become an important issue in recent years and by the way conducted studies regarding to this subject shows that the highest exergy destruction is observed in the combustor and afterburner modules. Therefore it is beneficial to perform analyses that are specific to the combustor exergy efficiency. This study includes the energy ηcc$\left( {{\eta _{cc}}} \right)$and exergy efficiencies ηex$\left( {{\eta _{ex}}} \right)$(thermo-efficiencies) of a tubular combustor for different inlet conditions. Both of the first law and second law efficiencies have been performed on the experimental data and efficiency trends are investigated for changing aerodynamic conditions. Combustor tests have been conducted in an atmospheric test rig and combustor air inlet temperatureT03$\left( {{T_{03}}} \right)$, air mass flow rate m˙a$\left( {{{\dot m}_a}} \right)$and fuel mass flow rate m˙f$\left( {{{\dot m}_f}} \right)$have been set for the pre-defined conditions. Moreover, exhaust gas emissions were measured by using a gas analyzer system. In the study, highest energy and exergy efficiencies have been obtained at minimum aerodynamic loading condition as 99.0 % and 70.2 % respectively. Moreover efficiencies have the lowest value as 92.7 % and 54.0 % at the maximum aerodynamic loading condition. To summarize, this study aims to show the energy and exergy trends by changing inlet conditions of a tubular combustor in the atmospheric test rig.

Noncovalent and electrostatic interactions facilitate the formation of complex networks through molecular self-assembly in biomolecules such as proteins and glycosaminoglycans. Self-assembling peptide amphiphiles (PA) are a group of molecules that can form nanofibrous structures and may contain bioactive epitopes to interact specifically with target molecules. Here, we report the presentation of cationic peptide sequences on supramolecular nanofibers formed by self-assembling peptide amphiphiles for cooperative enhanced antibacterial activity. Antibacterial properties of self-assembled peptide nanofibers were significantly higher than soluble peptide molecules with identical amino acid sequences, suggesting that the tandem presentation of bioactive epitopes is important for designing new materials for bactericidal activity. In addition, bacteria were observed to accumulate more rapidly on peptide nanofibers compared to soluble peptides, which may further enhance antibacterial activity by increasing the number of peptide molecules interacting with the bacterial membrane. The cationic peptide amphiphile nanofibers were observed to attach to bacterial membranes and disrupt their integrity. These results demonstrate that short cationic peptides show a significant improvement in antibacterial activity when presented in the nanofiber form.

Peripheral nerve injuries cause devastating problems for the quality of patients’ lives, and regeneration following damage to the peripheral nervous system is limited depending on the degree of the damage. Use of nanobiomaterials can provide therapeutic approaches for the treatment of peripheral nerve injuries. Electroactive biomaterials, in particular, can provide a promising cure for the regeneration of nerve defects. Here, a supramolecular electroactive nanosystem with tetra(aniline) (TA)-containing peptide nanofibers was developed and utilized for nerve regeneration. Self-assembled TA-conjugated peptide nanofibers demonstrated electroactive behavior. The electroactive self-assembled peptide nanofibers formed a well-defined three-dimensional nanofiber network mimicking the extracellular matrix of the neuronal cells. Neurite outgrowth was improved on the electroactive TA nanofiber gels. The neural differentiation of PC-12 cells was more advanced on electroactive peptide nanofiber gels, and these biomaterials are promising for further use in therapeutic neural regeneration applications.

Fabrication of supramolecular electroactive materials at the nanoscale with well-defined size, shape, composition, and organization in aqueous medium is a current challenge. Herein we report construction of supramolecular charge-transfer complex one-dimensional (1D) nanowires consisting of highly ordered mixed-stack π-electron donor–acceptor (D–A) domains. We synthesized n-type and p-type β-sheet forming short peptide-chromophore conjugates, which assemble separately into well-ordered nanofibers in aqueous media. These complementary p-type and n-type nanofibers coassemble viahydrogen bonding, charge-transfer complex, and electrostatic interactions to generate highly uniform supramolecular n/p-coassembled 1D nanowires. This molecular design ensures highly ordered arrangement of D–A stacks within n/p-coassembled supramolecular nanowires. The supramolecular n/p-coassembled nanowires were found to be formed by A–D–A unit cells having an association constant (KA) of 5.18 × 105M–1. In addition, electrical measurements revealed that supramolecular n/p-coassembled nanowires are approximately 2400 and 10 times more conductive than individual n-type and p-type nanofibers, respectively. This facile strategy allows fabrication of well-defined supramolecular electroactive nanomaterials in aqueous media, which can find a variety of applications in optoelectronics, photovoltaics, organic chromophore arrays, and bioelectronics.

Combustion of fuel finds its importance in heating, power production and transportation. The main objective of this study is to assess the performance of an air-blasted combustor using the exergy at different combustor exit temperatures (T4). Exergetic metrics of the combustor in a test rig were made between 1,100 < T4≤ 1500K. JP8 kerosene-type fuel was used for analysis. For the combustor, exergy efficiency was calculated to be between 49.3% and 59.4%. Furthermore, greatest exergy destruction is found at highest combustor exit temperature (138.7 kW at 1500 K), while the lower exergy destructions are found at 1102 K with the value of 90.7 kW. The methodology and the results of this study can be beneficial for further improvement, and development of similar combustor systems for designers.

Boric acid (BA) is an essential nutrient for plants and many organisms, but it has become an environmental contaminant because of widespread use. Pesticide and its compounds are a serious threat to aquatic organisms. This study was carried out to determine the histopathological effects of acute exposure to BA concentrations in rainbow trout. The fish were exposed to 102and 103mg/L concentrations of BA. Tissues were sampled at 6, 12, 24, 48 and 96 h. Histopathological alterations occurring in tissues were common in both doses of BA. Gill tissues showed lamellar oedema, cellulary infiltration, lamellar disorganization, degenerative changes and lamellar thickening. Kidneys had glomerular oedema and glomerulonephritis, degeneration of the tubulary epithelium, interstitial fibrosis and a hyaline cast within the tubular lumens. Muscle tissues displayed interstitial oedema and degenerative and atrophic changes to varying degrees in the myofibrils. Our study shows that BA can be toxic for rainbow trout and cause histopathological damage in fish tissue.

Chlorpyrifos is widely used to control agricultural pests associated with fruit, nut and vegetable crops, despite its toxic effects and potential brain alterations in aquatic organisms. This study was carried out to determine the in vivoand in vitroeffects of chlorpyrifos on rainbow trout brain acetylcholinesterase (AChE) enzyme activity. The fish were exposed to 2.25 µg/L (25% of 96 h LC50), 4.5 µg/L (50% of 96 h LC50) and 6.75 µg/L (75% of 96 h LC50) of chlorpyrifos for 24, 48, 72 and 96 h. In vitrostudies, inhibition constants (Ki) and half-maximal inhibitory concentration (IC50) values for chlorpyrifos were determined by Lineweaver–Burk graphs and by plotting activity percentage vs. [I], respectively. Enzyme activities were determined by a colorimetric method. In fish exposed to chlorpyrifos 2.25 and 4.5 µg/L, enzyme inhibition was not observed (p> 0.05); however, chlorpyrifos exposure to 6.75 µg/L for 72 and 96 h caused a significant decrease in enzyme activity (p< 0.05). The IC50value of chlorpyrifos was found to be 30 µg/L. These results show that chlorpyrifos may cause direct cellular injury in the brain, and suggest that AChE may be used as a bioindicator for toxicological studies.

El objetivo de este estudio fue hacer una revisión de las experiencias de un departamento de anestesiología con relación al uso del videolaringoscopio C-MAC®en intentos de intubación que fracasaron.

O objetivo deste estudo foi fazer uma revisão das experiências de um departamento de anestesiologia em relação ao uso do videolaringoscópio C-MAC em tentativas malsucedidas de intubação.

The purpose of this study was to review the experiences of an anesthesiology department regarding the use of a C-MAC videolaryngoscope in unexpected failed intubation attempts.

The aim was to determine the influence of the pneumoperitoneum at 10, 13, and 16 mm Hg on thromboelastograph (TEG) in laparoscopic cholecystectomy.

The number of obese patients has increased dramatically worldwide. Morbid obesity is associated with an increased incidence of medical comorbidities and restricts the application choices in anesthesiology. We report a successfully performed combined ultrasound-guided blockade of the femoral, tibial, and common peroneal nerve in a superobese patient. We present a case report of a 31-year-old, ASA-PS II, super obese man (190 kg, 180 cm, BMI: 58 kg/m2) admitted to the emergency department with a type II segmental tibia shaft fracture and ankle dislocation after a vehicle accident. After two failed spinal anesthesia attempts, we decided to apply a femoral block combined with a sciatic block. Femoral blocks were successfully performed with US guided in-plane technique. Separate blocks of the tibial and common peroneal nerves were planned after the sciatic nerve could not be located due to the thick subcutaneous tissue. We performed a tibial nerve block at 2 cm above the popliteal crease and common peroneal nerve at the level of the fibular head with US guided in-plane technique. The blocks were successful and no block-related complications were noted. Ultrasound guidance allows new approaches for multiple peripheral nerve blocks with low local anesthetic doses in obese patients.