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Fixed-wing unmanned aerial vehicles (UAVs) in the modern day have widespread applications in various reconnaissance, agriculture, military, and civilian operations. Their wide domain of application has placed the development of drone technology at the forefront. The energy harvesting in UAVs seems promising since it not only has the ability to lengthen flying time but also guarantees that no appreciable weight is added. The current article explores the concept of placing piezoelectric material patches on the UAV wing in order to extract energy from the vibration of the wing. This study uses a UAV's fixed NACA 2412 wing to harvest vibration energy by finding the location and placing a piezoelectric patch where it will produce the most voltage. The mode shapes generated are used to get the appropriate location to place the piezoelectric patch. The fixed-wing of a UAV with a piezo patch placed is subjected to a harmonically varying pressure load of 213.934 Pa and the behavior of the wing and its frequency response is analyzed in terms of displacement and voltage as output. The maximum voltage produced by the single piezoelectric patch is found about 0.11 V at the first mode shape of the wing. Embedding and increasing the patch at a location of high displacements help to harvest more energy and can be utilized for other purposes. [ABSTRACT FROM AUTHOR]

This research article focuses on improving the efficiency of an axial flow compressor stage, enhancing the stall margin, and optimizing flow parameters. Utilizing the NACA 65 series rotor airfoil with 12 blades, the study employs numerical simulations using the K-epsilon turbulence model. The model is validated with experimental data under specific boundary conditions, including a total pressure at the intake and a static pressure at the exit, initially set at atmospheric pressure. The outlet static pressure is incrementally increased until the rotor reaches stall. At this stall point, the tip injection method, a well-known active flow control technique, is implemented to mitigate flow instabilities. Injectors are placed at the leading edge of the rotor blades, distributed circumferentially. The tip injection parameters include 0.3% of the total mass flow rate, a pitch angle of 30 degrees and yaw angles ranging from −15 to +15 degrees. The analysis shows a stall margin improvement (SMI) of 14.26% with the 0.3% total mass flow rate injection. A decrease in the yaw angle reduces blockage and promotes smoother flow over the rotor blade, with the optimal stall margin enhancement occurring at an adverse yaw angle of −15 degrees. This study demonstrates significant SMI in the axial flow compressor rotor using specific active flow control parameters, particularly highlighting the critical role of adverse yaw angles in the tip injection method in enhancing stall margin, contributing to overall efficiency and stability.

Osteosarcoma (OS) is a primary malignant bone tumor in children and young adults because of its intertumoral heterogeneity and absence of molecular targets. This study aimed to elucidate the role of circular RNA in the pathogenesis of OS. Using bioinformatics analysis and OS clinical samples, we found that hsa_circ_0029634 formed during the splicing process of Zinc finger MYM-type containing 2 (circZMYM2) was highly expressed in OS tissues. Nuclear cap-binding protein subunit 2 regulated circZMYM2 bio-generation by binding to flanking sequences of ZMYM2 transcripts. In addition, knockdown circZMYM2 inhibited cell growth and metastasis in OS cell lines in vitro and inhibited tumor growth in vivo. Mechanistically, circZMYM2 competitively bound to FXR1 to regulate the translation of NACA and ARPC1B. CircZMYM2 may be a crucial regulator of OS tumorigenesis and a potential diagnostic and therapeutic biomarker for OS patients.

This research article focuses on improving the efficiency of an axial flow compressor stage, enhancing the stall margin, and optimizing flow parameters. Utilizing the NACA 65 series rotor airfoil with 12 blades, the study employs numerical simulations using the K-epsilon turbulence model. The model is validated with experimental data under specific boundary conditions, including a total pressure at the intake and a static pressure at the exit, initially set at atmospheric pressure. The outlet static pressure is incrementally increased until the rotor reaches stall. At this stall point, the tip injection method, a well-known active flow control technique, is implemented to mitigate flow instabilities. Injectors are placed at the leading edge of the rotor blades, distributed circumferentially. The tip injection parameters include 0.3% of the total mass flow rate, a pitch angle of 30 degrees and yaw angles ranging from -15 to +15 degrees. The analysis shows a stall margin improvement (SMI) of 14.26% with the 0.3% total mass flow rate injection. A decrease in the yaw angle reduces blockage and promotes smoother flow over the rotor blade, with the optimal stall margin enhancement occurring at an adverse yaw angle of -15 degrees. This study demonstrates significant SMI in the axial flow compressor rotor using specific active flow control parameters, particularly highlighting the critical role of adverse yaw angles in the tip injection method in enhancing stall margin, contributing to overall efficiency and stability. [ABSTRACT FROM AUTHOR]

Air multiplier fans, which are produced as an alternative to the convectional propellers used today, have come into prominence with the advantages providing in both efficiency and usage. In this study, three different blade profiles based on NACA 0012, NACA 1408, and EPPLER 1214 were used in the fan body. The design based on the NACA 0012 of body profile provided the highest flow rate. This profile was optimized using CFD analysis according to seven different geometrical parameters determined as the angle of attack, width, length, gap, inner and outer diameters, and tail length. The profile that provides less noise against the highest flow rate was determined as the optimal design. With CFD analysis, the sound pressure level of the optimal design was calculated by the k-ω and LES method, and the results were compared with each other. [ABSTRACT FROM AUTHOR]

Abstract Background Cystinosis is a rare autosomal recessive lysosomal storage disease, associated with high morbidity and mortality. Mutations in the CTNS gene disable a membrane protein responsible for the transport of cystine out of the lysosome. Loss of transporter function leads to intralysosomal cystine accumulation and long-term damage to various tissues and organs, including the kidneys, eyes, liver, muscles, pancreas, and brain. The only cystine-depletion therapy for treatment of cystinosis is cysteamine which requires frequent administration of high doses and often causes gastrointestinal pain as well as pungent sulfurous odor in patients. The current in vitro study evaluated antioxidants, N-acetylcysteine amide (NACA; NPI-001) and (2R,2R′)-3,3′-disulfanediyl bis(2-acetamidopropanamide) (diNACA; NPI-002), as potential treatments for cystinosis. Methods Cytotoxicity of cysteamine, NACA and diNACA was evaluated in cultured human cystinotic fibroblasts (HCFs). HCFs were cultured in 96 well plates incubated for 0–72 h in the presence of 25, 50 or 75 μM each of either cysteamine, NACA or diNACA along with an untreated control. Media was removed and cell viability assessed. Next, cystine-depleting activities of cysteamine, NACA and diNACA were screened in HCFs cell culture utilizing an inexpensive, proven colorimetric assay. HCFs were seeded and allowed to reach approximately 80% confluence before the addition of the test articles: 50 μM of either cysteamine, NACA or diNACA in media along with an untreated control. HCFs were incubated, harvested, and cystine was reduced to cysteine, the concentration of which was then determined per quantity of protein compared to a cysteine standard. Statistically significant cystine depletion was determined by paired t-test versus untreated control (p diNACA ≥ cysteamine. Therefore, further study of NACA and diNACA as potential treatments for cystinosis is warranted.

Reactive oxygen species (ROS) play a significant role in toxicity to the retina in a variety of diseases. N-acetylcysteine (NAC), N-acetylcysteine amide (NACA) and the dimeric di-N-acetylcysteine amide (diNACA) were evaluated in terms of protecting retinal cells, in vitro, in a variety of stress models. Three types of rat retinal cell cultures were utilized in the study: macroglial-only cell cultures, neuron-only retinal ganglion cell (RGC) cultures, and mixed cultures containing retinal glia and neurons. Ability of test agents to attenuate oxidative stress in all cultures was ascertained. In addition, capability of agents to protect against a variety of alternate clinically-relevant stressors, including excitotoxins and mitochondrial electron transport chain inhibitors, was also evaluated. Capacity of test agents to elevate cellular levels of reduced glutathione under normal and compromised conditions was also determined. NAC, NACA and diNACA demonstrated concentration-dependent cytoprotection against oxidative stress in all cultures. These three compounds, however, had differing effects against a variety of alternate insults to retinal cells. The most protective agent was NACA, which was most potent against the most stressors (including oxidative stress, mitochondrial impairment by antimycin A and azide, and glutamate-induced excitotoxicity). Similar to NAC, NACA increased glutathione levels in non-injured cells, although diNACA did not, suggesting a different, unknown mechanism of antioxidant activity for the latter. In support of this, diNACA was the only agent to attenuate rotenone-induced toxicity in mitochondria. NAC, NACA and diNACA exhibited varying degrees of antioxidant activity, i.e., protected cultured rat retinal cells from a variety of stressors which were designed to mimic aspects of the pathology of different retinal diseases. A general rank order of activity was observed: NACA ≥ diNACA > NAC. These results warrant further exploration of NACA and diNACA as antioxidant therapeutics for the treatment of retinal diseases, particularly those involving oxidative stress. Furthermore, we have defined the battery of tests carried out as the "Wood, Chidlow, Wall and Casson (WCWC) Retinal Antioxidant Indices"; we believe that these are of great value for screening molecules for potential to reduce retinal oxidative stress in a range of retinal diseases. • NACA, diNACA and NAC reduced stimulated superoxide production in cultured retinal cells. • NACA, diNACA and NAC increased levels of reduced glutathione in retinal cells exposed to oxidative stress. • NACA, diNACA and NAC reduced oxidant-induced cytotoxicity to cultured retinal cells. • NACA, diNACA and NAC exhibited varying degrees of protection against cultured rat retinal cells from a variety of toxins. • A general rank order of activity was observed: NACA ≥ diNACA > NAC. [ABSTRACT FROM AUTHOR]

The significance of using proper blade design is increasing with advancements in aviation technology. Wings are used in a variety of applications, including aircraft, drones, wind turbines, and more. In this study, Ansys version 2021 is used to do a CFD analysis on a NACA 0012 to study the effect of increasing the angle of attack on the coefficient of lift. Analyses have been performed using Ansys Fluent. The k-w turbulence model was used to analyze geometry, designed in SOLIDWORKS. At a speed of 32 m/s, several angles of attack have been evaluated from 0° to 20° to investigate lift and drag coefficient. The results of this study were compared with the literature for validation. It has been observed that increasing the angle of attack will increase the lift coefficient initially but after a specific angle, flow separation takes place and the lift coefficient starts decreasing with a further increase in the angle of attack

Prolyl hydroxylase domain protein 2 (PHD2)‐catalyzed modification of hypoxia‐inducible factor (HIF)‐α is a key event in oxygen sensing. We previously showed that the zinc finger of PHD2 binds to a Pro‐Xaa‐Leu‐Glu (PXLE) motif. Here, we show that the zinc finger binds to this motif in the ribosomal chaperone nascent polypeptide complex‐α (NACA). This recruits PHD2 to the translation machinery to cotranslationally modify HIF‐α. Importantly, this cotranslational modification is enhanced by a translational pause sequence in HIF‐α. Mice with a knock‐in Naca gene mutation that abolishes the PXLE motif display erythrocytosis, a reflection of HIF pathway dysregulation. In addition, human erythrocytosis‐associated mutations in the zinc finger of PHD2 ablate interaction with NACA. Tibetans, who have adapted to the hypoxia of high altitude, harbor a PHD2 variant that we previously showed displays a defect in zinc finger binding to p23, a PXLE‐containing HSP90 cochaperone. We show here that Tibetan PHD2 maintains interaction with NACA, thereby showing differential interactions with PXLE‐containing proteins and providing an explanation for why Tibetans are not predisposed to erythrocytosis. Synopsis: Mechanistic understanding of PHD2, a key enzyme in the HIF pathway, is incomplete. This work shows that the zinc finger of PHD2 binds to a Pro‐Xaa‐Leu‐Glu motif in the ribosomal chaperone NACA, allowing PHD2 to cotranslationally modify the nascent HIF‐α polypeptide. The cotranslational modification of HIF‐α is enhanced by a translation pause sequence in HIF‐α.Mice with a knock‐in mutation in the Naca gene that ablates interaction of Naca with Phd2 display erythrocytosis.Human erythrocytosis‐associated mutations in the PHD2 gene result in impaired binding of PHD2 to NACA.Tibetan‐associated mutations in the PHD2 gene result in preserved binding of PHD2 to NACA and provide an explanation for why Tibetans are not predisposed to erythrocytosis. [ABSTRACT FROM AUTHOR]

Vertical axis wind turbines such as Darrieus turbines are a very interesting category of low wind speed domestic wind turbines. Further research work is needed to enhance their efficiency to fulfill the higher demand in small applications for power generation. The main objective of this work is to find a Darrieus turbine design to boost the starting capacity of the turbine through an opening located at the lower surface of the airfoil. We carried out a thorough CFD (Computational Fluid Dynamics) investigation to determine the impact of the opening position on the Darrieus rotor's output. This new type of airfoil uses a standard NACA 0015 profile and a profile with an opening on the lower surface of the profile. Different sizes of the opening in a symmetrical profile are evaluated through the CFD method to predict the Cp and CT of this H-Darrieus turbine design. Five sections were designed to describe the research of this new H-Darrieus rotor. Generally speaking, the results showed that the Cp decreases with the opening ratio, the desirable rotors with the lower surface opening ratio are 0.12 to 0.36 considering this with the low CpLP. [ABSTRACT FROM AUTHOR]

Recently, two leading organizations on student experiences in colleges and universities (i.e., NACA and NIRSA) issued a call for increased scholarship in the area of transferable work skills (identified by NACE) in student employees within campus recreation programs. An exploratory case study was conducted to provide insight into what student employees learn and what campus recreation staff teach (in regards to these transferable skills) at a campus recreation program at a midsized regional university in the southwestern United States. Data were collected via a survey of both student employees and professional staff concerning the opportunities to learn these skills. Focus groups were also conducted. The results demonstrate that student workers learn through doing. Aquatics was one key area identified where staff clearly teach and student employees must learn transferable skills. The results suggest that student employees need to be provided with opportunities to critically reflect on skills gained. [ABSTRACT FROM AUTHOR]

Background: Cystinosis is a rare autosomal recessive lysosomal storage disease, associated with high morbidity and mortality. Mutations in the CTNS gene disable a membrane protein responsible for the transport of cystine out of the lysosome. Loss of transporter function leads to intralysosomal cystine accumulation and long-term damage to various tissues and organs, including the kidneys, eyes, liver, muscles, pancreas, and brain. The only cystine-depletion therapy for treatment of cystinosis is cysteamine which requires frequent administration of high doses and often causes gastrointestinal pain as well as pungent sulfurous odor in patients. The current in vitro study evaluated antioxidants, N-acetylcysteine amide (NACA; NPI-001) and (2R,2R')-3,3'-disulfanediyl bis(2-acetamidopropanamide) (diNACA; NPI-002), as potential treatments for cystinosis.Methods: Cytotoxicity of cysteamine, NACA and diNACA was evaluated in cultured human cystinotic fibroblasts (HCFs). HCFs were cultured in 96 well plates incubated for 0-72 h in the presence of 25, 50 or 75 μM each of either cysteamine, NACA or diNACA along with an untreated control. Media was removed and cell viability assessed. Next, cystine-depleting activities of cysteamine, NACA and diNACA were screened in HCFs cell culture utilizing an inexpensive, proven colorimetric assay. HCFs were seeded and allowed to reach approximately 80% confluence before the addition of the test articles: 50 μM of either cysteamine, NACA or diNACA in media along with an untreated control. HCFs were incubated, harvested, and cystine was reduced to cysteine, the concentration of which was then determined per quantity of protein compared to a cysteine standard. Statistically significant cystine depletion was determined by paired t-test versus untreated control (p < 0.05).Results: Neither cysteamine, NACA nor diNACA at 25, 50 or 75 μM caused cytotoxicity in HCFs. Treatment with all tested concentrations (25, 50 or 75 µM) of either NACA or diNACA at 48 or 72 h resulted in statistically significant increases in cell viability, relative to untreated control, whereas the higher concentrations (50 or 75 µM) of cysteamine achieved statistical significance at both timepoints but not the lowest concentration (25 µM). All test articles depleted cystine from HCFs compared to control. NACA depletion of cystine was statistically superior to cysteamine at 6, 24 and 48 h and numerically greater at 72 h. DiNACA depletion of cystine was statistically superior to cysteamine at 6 and 48 h, slightly numerically greater at 24 h and slightly less at 72 h.Conclusions: NACA and diNACA were non cytotoxic to HCFs and significantly increased cell viability. Cystine reduction was determined as percent of control after incubation with 50 µM of NACA, diNACA or cysteamine in HCFs cell culture for 6, 24, 48 and 72 h. Of the three test articles, NACA exhibited most rapid and greatest potency in cystine reduction. Rank order potency for cystine reduction over time was observed, NACA > diNACA ≥ cysteamine. Therefore, further study of NACA and diNACA as potential treatments for cystinosis is warranted. [ABSTRACT FROM AUTHOR]

In the last years, Fluent and OpenFoam are the two most reliable CFD software used in simulations of different flow fields in both academic and industry. In this study, the performance of these two CFD simulation software relative to each other was determined for the same boundary conditions for a selected flow area. The highlight of OpenFoam CFD software is that it is free software with open source. In this context, our primary goal is to lead the spread of open-source and free software in the implementation of engineering processes in our country. As the flow area, an airfoil with Naca 2415 section manufactured by Harran-Ravens team was selected for Teknofest competition. As a result of the simulations carried out, the aerodynamic forces and moments that affect the airfoil have been determined. In terms of lift force, the deviation between the two simulations is 6%, while in the drag force the said deviation increases up to 15.5%. Also, the lift and drag coefficient calculated by both simulation results are in good agreement with Airfoil Tools database.

Osteosarcoma (OS) is a primary malignant bone tumor in children and young adults because of its intertumoral heterogeneity and absence of molecular targets. This study aimed to elucidate the role of circular RNA in the pathogenesis of OS. Using bioinformatics analysis and OS clinical samples, we found that hsa&#95;circ&#95;0029634 formed during the splicing process of Zinc finger MYM-type containing 2 (circZMYM2) was highly expressed in OS tissues. Nuclear cap-binding protein subunit 2 regulated circZMYM2 bio-generation by binding to flanking sequences of ZMYM2 transcripts. In addition, knockdown circZMYM2 inhibited cell growth and metastasis in OS cell lines in vitro and inhibited tumor growth in vivo . Mechanistically, circZMYM2 competitively bound to FXR1 to regulate the translation of NACA and ARPC1B. CircZMYM2 may be a crucial regulator of OS tumorigenesis and a potential diagnostic and therapeutic biomarker for OS patients., Competing Interests: All authors declare that they have no competing interests., (© 2024 The Authors.)

In the present study, the roles of a novel long non-coding RNA (lncRNA), lnc-GD2H, in promoting C2C12 myoblast proliferation and differentiation and muscle regeneration were investigated by quantitative polymerase chain reaction, western blotting, Cell Counting Kit-8, 5-ethynyl-2′-deoxyuridine (EdU), immunofluorescence staining, luciferase reporter, mass spectrometry, pulldown, chromatin immunoprecipitation, RNA immunoprecipitation assay, wound healing assays, and cardiotoxin (CTX)-induced muscle injury assays. It was observed that lnc-GD2H promoted myoblast proliferation as evidenced by the enhancement of the proliferation markers c-Myc, CDK2, CDK4, and CDK6, percentage of EdU-positive cells, and rate of cell survival during C2C12 myoblast proliferation. Additional experiments confirmed that c-Myc bound to the lnc-GD2H promoter and regulated its transcription. lnc-GD2H promoted cell differentiation with enhanced MyHC immunostaining as well as increased expression of the myogenic marker genes myogenin (Myog), Mef2a, and Mef2c during myoblast differentiation. Additional assays indicated that lnc-GD2H interacted with NACA which plays a role of transcriptional regulation in myoblast differentiation, and the enrichment of NACA at the Myog promoter was impaired by lnc-GD2H. Furthermore, inhibition of lnc-GD2H impaired muscle regeneration after CTX-induced injury in mice. lnc-GD2H facilitated the expression of proliferating marker genes and formed a feedback loop with c-Myc during myoblast proliferation. In differentiating myoblasts, lnc-GD2H interacted with NACA to relieve the inhibitory effect of NACA on Myog, facilitating Myog expression to promote differentiation. The results provide evidence for the role of lncRNAs in muscle regeneration and are useful for developing novel therapeutic targets for muscle disorders.

Vertical axis wind turbines such as Darrieus turbines are a very interesting category of low wind speed domestic wind turbines. Further research work is needed to enhance their efficiency to fulfill the higher demand in small applications for power generation. The main objective of this work is to find a Darrieus turbine design to boost the starting capacity of the turbine through an opening located at the lower surface of the airfoil. We carried out a thorough CFD (Computational Fluid Dynamics) investigation to determine the impact of the opening position on the Darrieus rotor’s output. This new type of airfoil uses a standard NACA 0015 profile and a profile with an opening on the lower surface of the profile. Different sizes of the opening in a symmetrical profile are evaluated through the CFD method to predict the Cp and CT of this H-Darrieus turbine design. Five sections were designed to describe the research of this new H-Darrieus rotor. Generally speaking, the results showed that the Cp decreases with the opening ratio, the desirable rotors with the lower surface opening ratio are 0.12 to 0.36 considering this with the low CpLP.

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El sistema de frenos de un automóvil debe satisfacer un conjunto complejo de requerimientos importantes, tales como la seguridad vial, la cual se basa en función del arreglo geométrico y el tipo de material. El objetivo de este trabajo es proponer un nuevo arreglo geométrico para la optimización del flujo de aire en un disco de freno automotriz, teniendo en cuenta pilares de ventilación fundamentados en perfiles aerodinámicos tipo NACA 66-209. Para sustentar esta propuesta de diseño, se llevó a cabo la construcción de un prototipo a escala 1:1 por medio de manufactura aditiva y al igual que el diseño de una instalación que permite el montaje del disco para medir el campo de velocidades generado en la zona de succión y descarga mediante el uso de la Velocimetría por Imágenes de Partícula (VIP). La validación del arreglo geométrico se efectuó bajo cinco (5) condiciones de velocidad angular: 541, 641, 741, 841 y 941 rpm. Los resultados obtenidos muestran la optimización de la velocidad del aire en la zona de de carga de 0,1151 y 0,2317 m/s a 35 rpm por evidenciar la importancia de diseños experimentales con los cuales se pueda mejorar la geometría de los frenos de disco, autoventilados y de esta manera garantizar la eficiencia y seguridad del sistema.

Vertical axis wind turbines received renewed attention for increasing offshore wind energy harvesting and in urban environments. This turbine reflects a specific type of technology that generates electricity from wind, which is renewable sources of energy. This research explores the effect of blade profile modifications on the VAWT aerofoil NACA0012 and NACA2415. Analysis of the lift/drag coefficient and calculation of the average torque/self-starting potential of NACA0012 and NACA2415 for NACA0012, as this is a significantly better measure of the power generated at different pitch angles and comparison of both profiles. The dataset is created using Computational Fluid Dynamics (CFD) simulations, which were performed in ANSYS-Fluent. Various parameters, such as the number, thickness, and angle of attack of the Reynolds no. were investigated. The aerodynamics of the wind turbine blade is shown to increase the optimized form of the modified aerofoil. [ABSTRACT FROM AUTHOR]

This work presents selected results of an unconventional aircraft development campaign. Engine installation at the rear part of the fuselage imposed design constraints for air intakes that should be used for cooling purposes. Trial and error flight tests increased the development cost and time which required a more sophisticated analysis through computational fluid dynamics (CFD) techniques and robust semiempirical approach. The carried-out investigation of the air intakes started with an empirical approach from guidelines for designing NACA and scoops. Numerical studies via computational fluid dynamics were performed with the air intakes installed in the aircraft fuselage. An analysis based on the air intake efficiency, drag and the effect of angle of attack are detailed in this work. Different air intakes designs, such as scoops of different shapes, were evaluated seeking for improved air intake efficiency and low drag while providing enough air for cooling the engine compartment. The results showed that the numerical approach used herein decreased the development cost and time of the aircraft, providing a reasonable low-cost approach and leading to a design selection more easily. Based on the current approach the canard airplane geometry was changed to account for the new selected air intake for engine cooling purposes.

Introduction-- The braking system of a car must work safely and predictably in any circumstance, which implies having a stable level of friction, in any condition of temperature, humidity, and salinity of the environment. For the correct design and operation of the brake discs, it is necessary to consider different aspects, such as geometry, type of material, mechanical resistance, maximum temperature, thermal deformation, resistance to cracking, among others. Objective-- The objective of this study was to analyze the behavior of temperature and velocity of heat flow in the disc brake ventilation duct with ventilation pillars type NACA 66-29 using Computational Fluid Dynamics (CFD). Methodology-- This is the design software Solid-Works simulations for analyzing the behavior of the fluid (air) in terms of speed and heat dissipation capacity. Results-- The numerical results for the heat flow through the ventilation channels are compared with the results mathematically. The numerical results that the discs performed well under severe operating conditions (80 km/h and an ambient temperature of 12°C). It is very important in the design of the brake disc to select the appropriate geometry, particularly the number and cross section of the ducts, and the type of material. Conclusions-- The numerical methods offer advantages to select the geometry and the material and the flow mode of the fluid to optimize the heat dissipation to provide the maximum performance for the maintained components. [ABSTRACT FROM AUTHOR]

This work presents selected results of an unconventional aircraft development campaign. Engine installation at the rear part of the fuselage imposed design constraints for air intakes that should be used for cooling purposes. Trial and error flight tests increased the development cost and time which required a more sophisticated analysis through computational fluid dynamics (CFD) techniques and robust semiempirical approach. The carried-out investigation of the air intakes started with an empirical approach from guidelines for designing NACA and scoops. Numerical studies via computational fluid dynamics were performed with the air intakes installed in the aircraft fuselage. An analysis based on the air intake efficiency, drag and the effect of angle of attack are detailed in this work. Different air intakes designs, such as scoops of different shapes, were evaluated seeking for improved air intake efficiency and low drag while providing enough air for cooling the engine compartment. The results showed that the numerical approach used herein decreased the development cost and time of the aircraft, providing a reasonable low-cost approach and leading to a design selection more easily. Based on the current approach the canard airplane geometry was changed to account for the new selected air intake for engine cooling purposes. [ABSTRACT FROM AUTHOR]

In the last years, Fluent and OpenFoam are the two most reliable CFD software used in simulations of different flow fields in both academic and industry. In this study, the performance of these two CFD simulation software relative to each other was determined for the same boundary conditions for a selected flow area. The highlight of OpenFoam CFD software is that it is free software with open source. In this context, our primary goal is to lead the spread of open-source and free software in the implementation of engineering processes in our country. As the flow area, an airfoil with Naca 2415 section manufactured by Harran-Ravens team was selected for Teknofest competition. As a result of the simulations carried out, the aerodynamic forces and moments that affect the airfoil have been determined. In terms of lift force, the deviation between the two simulations is 6%, while in the drag force the said deviation increases up to 15.5%. Also, the lift and drag coefficient calculated by both simulation results are in good agreement with Airfoil Tools database. [ABSTRACT FROM AUTHOR]

Vertical axis wind turbines received renewed attention for increasing offshore wind energy harvesting and in urban environments. This turbine reflects a specific type of technology that generates electricity from wind, which is renewable sources of energy. This research explores the effect of blade profile modifications on the VAWT aerofoil NACA0012 and NACA2415. Analysis of the lift/drag coefficient and calculation of the average torque/self-starting potential of NACA0012 and NACA2415 for NACA0012, as this is a significantly better measure of the power generated at different pitch angles and comparison of both profiles. The dataset is created using Computational Fluid Dynamics (CFD) simulations, which were performed in ANSYS-Fluent. Various parameters, such as the number, thickness, and angle of attack of the Reynolds no.were investigated. The aerodynamics of the wind turbine blade is shown to increase the optimized form of the modified aerofoil.

Anxiety disorders are highly prevalent and a leading cause of disability worldwide. Their etiology is related to stress, an adaptive response of the organism to restore homeostasis, in which oxidative stress and glutamatergic hyperactivity are involved. N-Acetylcysteine (NAC) is a multitarget approved drug proved to be beneficial in the treatment of various mental disorders. Nevertheless, NAC has low membrane permeability and poor bioavailability and its limited delivery to the brain may explain inconsistencies in the literature. N-Acetylcysteine amide (AD4) is a synthetic derivative of NAC in which the carboxyl group was modified to an amide. The amidation of AD4 improved lipophilicity and blood-brain barrier permeability and enhanced its antioxidant properties. The purpose of this study was to investigate the effects of AD4 on behavioral and biochemical parameters in zebrafish anxiety models. Neither AD4 nor NAC induced effects on locomotion and anxiety-related parameters in the novel tank test. However, in the light/dark test, AD4 (0.001 mg/L) increased the time spent in the lit side in a concentration 100 times lower than NAC (0.1 mg/L). In the acute restraint stress protocol, NAC and AD4 (0.001 mg/L) showed anxiolytic properties without meaningful effects on oxidative status. The study suggests that AD4 has anxiolytic effects in zebrafish with higher potency than the parent compound. Additional studies are warranted to characterize the anxiolytic profile of AD4 and its potential in the management of anxiety disorders. [ABSTRACT FROM AUTHOR]

A partir de la línea de investigación del PI 29B163 del año 2015 y continuando su temática, el presente informe trata el estudio de las particularidades de una turbina hidrocinética de acuerdo a las características definidas para la construcción de un prototipo a futuro, teniendo en cuenta la potencia de la demanda estimada en el primer informe. Por lo tanto, según las partes de la turbina, inicialmente se detallan las características del rotor que captura la energía cinética del agua para obtener energía eléctrica luego de la conversión hidromecánica y electromagnética. Debido a que el rotor es la parte conversora de energía hidráulica en mecánica de la turbina, es relevante detallar cómo son sus álabes, por ello inicialmente se detallan las propiedades que caracterizan a cualquier perfil de álabes y luego se detallan los utilizados por las turbinas hidrocinéticas del tipo NACA. Luego, por medio del software QBlade, se realiza un cálculo hidrodinámico iterativo, el cual se realiza sección por sección para diferentes posiciones del álabe a lo largo del radio del rotor. A partir del análisis sobre de los resultados de dichas simulaciones, se determina el perfil óptimo para nuestro prototipo de turbina de acuerdo a las características definidas.

Pollution free power production, quick installation and commissioning capability, less operation and maintenance cost and taking benefit of by means of free and renewable energies are all advantages of using wind turbines as an power generators. Along with these advantages, the main drawback of this source is the conditional nature of wind flow. Therefore, using reliable and efficient apparatus is necessary in order to get as much as energy from wind during the limited period of time that it flows strongly. Wind power is the fastest increasing renewable energy resource and wind power penetration in power systems increases at a significant rate. The high access of wind power into power systems in the present and near future will have several impacts on their planning and operation. A wind turbine transforms the kinetic energy in the wind to mechanical energy in a shaft and ultimately into electrical energy in a generator. Turbine blade is the mainly important part of any wind turbine. In this paper we consider single airfoil NACA 0018 and done CFD analysis at different blade angles 00,100,150 and 300 with constant wind velocity of 6 m/s. The analysis results show that blade angle 15º gives best possible power. [ABSTRACT FROM AUTHOR]

Abstract As wind energy technology is growing rapidly in the energy production sector, Vertical Axis Wind Turbines (VAWTs) are coming to the fore to tackle areas with low wind speeds. The choice of optimum configuration of these VAWTs can not only maximize their performance but is a deterministic feasibility factor for their deployment. In this study, the Joukowski airfoil is reconsidered as potential rotor airfoil for VAWT. Its performance is compared against classical symmetrical NACA0012 and cambered NACA4312 blades. The investigation is carried out using high resolution CFD modelling. Results reveals the higher performance of the Joukowski airfoil over the classical symmetrical and cambered NACA. This dominance assessed by the attained higher blade lift as well as higher torque and power coefficient almost over the entire operable tip speed ratio. It was also found that cambered blades, improve the overall performance of the VAWT compared to the symmetrical baseline with a better power coefficient, at a lower tip speed ratio. In general, the rotor develops more consistent and homogenized torque at a higher tip speed ratio. The attained improvement in the torque using Joukowski however negatively affected the self-starting ability of the VAWT. [ABSTRACT FROM AUTHOR]

The automotive braking system must meet a complex set of requirements, among which safety is the most important, which is based on the function of the geometric arrangement and the type of material. The objective of this work is to propose a new geometric arrangement for the optimization of the air flow in an automotive brake disc, considering ventilation pillars founded on aerodynamic profiles type NACA 66-209. To support this design proposal, a 1: 1 scale prototype was made by means of additive manufacturing and an installation was also designed, which allows the assembly of the disk to measure the velocity field generated in the suction and discharge zone through the use of the Velocimetry by Particle Images (VPI). Validation of the geometric arrangement was performed under five (5) angular velocity conditions: 541, 641, 741, 841 and 941 rpm. The results obtained from the optimization of air velocity in the discharge zone of 0.1151 and 0.2317 m/s at 35 rpm. The results show the importance of experimental designs with which the geometry of self-ventilated disc brakes can be improved, thus guaranteeing the efficiency and safety of the system. [ABSTRACT FROM AUTHOR]

Parallel-sided foil sections are used for centerboards and rudders in sailing dinghy classes and also for struts placed in a fluid flow. The objective of this work is to create a systematic series of parallel-sided sections to be used under different conditions, with an emphasis on the sailing dinghies 470, 420 and Optimist. The loss, and surprisingly the gain, in performance relative to 4-digit NACA sections are also investigated. A 2D Reynolds-averaged Navier–Stokes solver is used with the k-ω SST turbulence model and the gamma transition criterion. A verification study is carried out based on four grids of systematically varied density, and results compared with experimental data on a NACA 64-006 section. The parallel-sided sections are modeled with rational Bézier curves whose geometrical parameters permit to link the shape of the profile to physical variables, which are systematically varied. Three Reynolds numbers and two angles of attack are investigated. Systematic plots show the influence of the trailing edge angle and nose radius for the different section families, and the optimum combination is presented in a table. Physical explanations of the trends, and of the exceptions, are given in the paper, using flow visualizations as well as pressure and friction plots.

Highlights • Meth and Tat synergistically increased cell death in dose- and time-dependent manners. • Meth and Tat-induced autophagy and apoptosis in vitro and in vivo. • NACA confers protection against Tat- and/or Meth-induced and/or autophagy through mTOR signaling in vitro and in vivo. Abstract Methamphetamine (Meth) is an addictive psychostimulant whose abuse is intimately linked to increased risks for HIV-1 infection. Converging lines of evidence indicate that Meth also aggravates the symptoms of HIV-associated neurocognitive disorders (HAND), though the underlying mechanisms remain poorly understood. By using the lipophilic antioxidant N -acetylcysteine amide (NACA) as an interventional agent, we examined the roles of oxidative stress in autophagy and apoptosis induced by HIV-Tat (the transactivator of transcription) , Meth or their combined treatment in human SH-SY5Y neuroblastoma cells and in the rat striatum. Oxidative stress was monitored in terms of the production of intracellular reactive oxygen species (ROS) and antioxidant reserves including glutathione peroxidase (GPx) and Cu ,Zn- superoxide dismutase (SOD). NACA significantly reduced the level of ROS and restored GPx and SOD to levels comparable to that of normal control, implying a cytoprotective effect of NACA against oxidative stress elicited by Tat- and/or Meth. Protein expression of mammalian target of rapamycin (mTOR) was measured in SH-SY5Y cells and in the rat striatum to further explore the underlying mechanism of NACA protect against oxidative stress. The results support a beneficial effect of NACA in vivo and in vitro through rectification of the mTOR signaling pathway. Collectively, our study shows that NACA protects against Meth and/or Tat-induced cellular injury in vitro and in the rat striatum in vivo by attenuating oxidative stress, apoptosis and autophagy, at least in part, via modulation of mTOR signaling. [ABSTRACT FROM AUTHOR]

Wind energy has been seen as one of the most suitable sources of renewable energy. Wind energy is low cost when compared the other sources. Therefore, wind energy can gain an edge over the fossil-fired power plants. Aerodynamic efficiency of the airfoil is very crucial for aerodynamic efficiency of the wind turbine. The primary purpose of our study was to analyze the NACA0012 and NACA4412 airfoil at various attack angles with constant Reynolds number and to examine the effects of the symmetrical and asymmetrical profiles of the airfoil. Analysis of aerodynamic performance of NACA0012 and NACA4412 airfoil were performed with using ANSYS Fluent program. Also, lift coefficients and drag coefficients were calculated at various attack angles. According to calculations, optimum attack angles were found for each profile. Finally, NACA0012 and NACA4412 airfoils were discussed and reported in terms of their airfoil performances. [ABSTRACT FROM AUTHOR]