bluuebunny/crossref_metadata_2025 huggingface dataset:
HeliUM 2 Flight Dynamic Simulation Model: Development, Technical Concepts, and Applications
Authors:   University of Maryland, Celi Roberto
Published: October 2024

HeliUM 2 is the name given to a rotorcraft flight dynamic simulation developed over the last three decades as a teaching and research tool by faculty and students at the University of Maryland. The paper summarizes the history of the development of the simulation. The general architecture of the simulation is described next. The model is primarily composed of a computational kernel in the form of a system of nonlinear ordinary differential equations (ODEs), although it is possible to include components not in ODE form. Solution algorithms are described for trim, linearized analyses, time marching response, and optimization. Illustrative results are presented for several aircraft configurations.
Sensitivity Study Of A Small Maritime Rotary UAS Operating In A Turbulent Airwake
Authors:   University of Liverpool, Fell Thomas ,   University of Lincoln, Owen Ieuan ,   Defence Science and Technology Organisation, Manso Sylvain , White Mark , Jump Michael
Published: October 2024

This paper describes helicopter model development work which will be used in the next stage of a research project to establish flying qualities requirements for Unmanned Aircraft Systems (UAS) operating in Maritime Environments. A new T-REX helicopter model, classed as a Mini UAS, has been built in the FLIGHTLAB simulation environment. A brief description of the model set up is provided alongside some of the core model parameters. A simple rotor optimization study was completed to assess the rotor for both hover and 30knots airspeed; the rotor parameters chosen were found to be a good compromise between these flight conditions. A frequency response analysis was also completed and the results compared to two other aircraft models; an RMAX helicopter and an aircraft similar to an SH-60B (Seahawk). These aircraft were placed in an unsteady ship airwake to assess the effect of turbulence with decreasing aircraft size. Although the smaller aircraft exhibit higher bandwidth in pitch and roll response, they were found to experience significantly larger disturbances in translation and rotational accelerations. This can be attributed to their reduced mass and inertia characteristics.
Joint Future Vertical Lift Initiative
Authors:   US Army, Bentley Erskine , Sission Larry
Published: October 2024

The Department of Defense (DOD) will design, develop, and field a fleet of air vehicles that will ensure the United States' dominance in the vertical lift domain through the 21st century and beyond. DOD will aggressively pursue the most capable aircraft at the best value by minimizing development, acquisition, and life cycle costs through Joint solutions of multi-role, common core technologies, architectures, and training, emphasizing the ability to conduct safe, reliable and continuous operations world-wide in all environmental conditions. Future Vertical Lift (FVL) is a revolutionary approach to vertical lift capabilities development across Joint operations and is aligned with the DOD Strategic Guidance. Strategic advances in capabilities include: worldwide self deployment; twice the average speed of the current fleet; twice the average range of the current fleet; increased payloads; worldwide operations; increased survivability; common systems approach; buildable and affordable; and is informed by government and industry technology development.
CHOPPA-M: Development, Capabilities and Applications to Helicopter Operations Research
Authors:   University of Glasgow, Ireland Murray ,   Defence Science and Technology Organisation, Chandran Arvind , Anderson David , Thomson Douglas , Ferguson Kevin , Ibal Gokhan
Published: October 2024

CHOPPA-M is a multi-resolution, multi-agent simulation framework developed to complement the existing CHOPPA (Combined Helicopter OPerations and Performance Analysis) framework. Like CHOPPA, it is designed to support operations research methods through simulation. It does so by presenting a consistent user interface and architecture for the modelling of autonomous systems across a variety of physical environments. These autonomous systems, or agents, may then participate in a pre-defined operational scenario. This describes CHOPPA-M's scene/vignette approach. In this paper, the background, architecture and user interface of CHOPPA-M are described. The development of some of the software's agent models are detailed and then employed in a case study: a maritime surveillance helicopter participating in a search and engage operation. From this case study, some conclusions are drawn. Finally, the future direction of CHOPPA-M is discussed.
Increased Industry Safety Through Education Technology
Authors:   Bell Helicopter Textron Inc., Vasey Clyde , Fialho Zekiel , Gralish Mike , Wormington Larry
Published: October 2024

Safety is important in the daily operations of any business, but in the aviation industry, it is paramount. Because each mission, whether critical or routine, relies so heavily on a safe flight environment, pilot and maintenance training must meet the highest educational standards available. To accomplish this, aviation training facilities have to find instructional methods that mimic, as closely as possible, actual flight and maintenance conditions. For practical training, actual aircraft are used for flight and maintenance instruction. For simulated practical training, full-flight simulators and high fidelity flight training devices (FTDs) are used. These methods, while highly effective, are also costly. Time and availability for such flight and simulator devices is also an issue. To train students in a cost-effective, timely manner, aviation industries demand a classroom-based solution. This paper explores a new approach to enhancing training effectiveness through education technology that increases student engagement and retention in the classroom. By using a 3D interactive software engine to build near photo-realistic aircraft system models, the classroom training experience is greatly enhanced, allowing students to learn theory-based aircraft information in a virtual environment. An engaged student learns the material and retains it at a higher cognitive level. This retention leads to safer, more professionally trained pilots and maintainers.
All-Electric Fuel and Oil Control System Demonstration on the T55 Engine
Authors:   Triumph Engine Control Systems, Brauer Richard , Busky Theodore , Niebanck Robert
Published: October 2024

Triumph Engine Control Systems developed and demonstrated a new all-electric fuel and oil control system for the Honeywell T55 turbo-shaft engine. The system replaces the current mechanically driven system with an electrically driven system. The new system performed the functions of the existing mechanical controls while also highlighting unique capabilities and advantages. For example, mechanical systems are subject to the energy-wasting constraint that pump flow must be proportional to engine speed. The electrical system removes this constraint by controlling its pumps to deliver only the fuel and oil flow actually needed. The fuel system provides fully redundant pumps, motors, and control electronics, providing enhanced failure accommodation. The developers adjusted control system flow schedules and pressures with software changes, providing great flexibility in development. Triumph demonstrated equivalent or better performance than the existing control system on a T55 engine under test at the US Army's RAPTR test facility.
Multi-Objective Optimization of a Regenerative Rotorcraft Powerplant: Quantification of Overall Engine Weight and Fuel Economy
Authors:   Cranfield University, Ali Fakhre ,   NOESIS Solutions, d'Ippolito Roberto , Tzanidakis Konstantinos , Goulos Ioannis , Vassilios Pachidis
Published: October 2024

A computationally efficient and cost effective simulation framework has been implemented to perform design space exploration and multi-objective optimization for an advanced regenerative rotorcraft powerplant configuration at mission level. The proposed framework is developed by coupling a comprehensive rotorcraft mission analysis code with a design space exploration and optimization package. The overall approach is deployed to design and optimize the powerplant of a reference twin-engine light rotorcraft, modelled after the Bo105 helicopter, manufactured by Airbus Helicopters. Firstly, a sensitivity analysis of the regenerative engine is carried out to quantify the interrelationship between the engine thermodynamic cycle design parameters, engine weight, and overall mission fuel economy. Secondly, through the execution of a multi-objective optimization strategy, a Pareto front surface is constructed, quantifying the optimum trade-off between the fuel economy offered by a regenerative engine and the associated weight penalty. The optimum sets of cycle design parameters obtained from the structured Pareto front suggest that the employed heat exchanger effectiveness is the key design parameter affecting the engine weight and fuel efficiency. Furthermore, through quantification of the benefits suggested by the acquired Pareto front, it is shown that, the fuel economy offered by the simple cycle rotorcraft engine can be substantially improved with the implementation of regeneration technology, without degrading the payload-range and airworthiness (One-Engine-Inoperative) requirements of the rotorcraft.
Concepts for Multi-Speed Rotorcraft Drive System - Status of Design and Testing at NASA GRC
Authors:   NASA John H. Glenn Research Center, Stevens Mark , Lewicki David , Handschuh Robert
Published: October 2024

In several studies and on-going developments for advanced rotorcraft, the need for variable/multi-speed capable rotors has been raised. Speed changes of up to 50% have been proposed for future rotorcraft to improve vehicle performance. A rotor speed change during operation not only requires a rotor that can perform effectively over the operating speed/load range, but also requires a propulsion system possessing these same capabilities. A study was completed investigating possible drive system arrangements that can accommodate up to a 50% speed change. Key drivers were identified from which simplicity and weight were judged as central. This paper presents the current status of two gear train concepts coupled with the first of two clutch types developed and tested thus far with focus on design lessons learned and areas requiring development. Also, a third concept is presented, a dual input planetary differential as leveraged from a simple planetary with fixed carrier.
Aluminum Metal Matrix Composite Liner Testing
Authors:   Sikorsky Aircraft, Hansen Bruce ,   US Army, Fetty Jason , Demers Timothy , Baker Treven
Published: October 2024

Bearing liners are used in rotorcraft gearboxes to reduce wear between the bearing race and housing during aircraft operations. Bearing liners are typically made of steel, but a new aluminum Metal Matrix Composite (MMC) bearing liner material is currently being developed under the Future Advanced Rotorcraft Drive System (FARDS) program. These new bearing liners have the benefit of reduced weight compared to existing steel liners. Seeded fault testing was performed which demonstrated the liners ability to withstand the loads generated due to failing bearings and still left the housing assembly in serviceable condition after removal. The test was in support of a viability study evaluating use of aluminum MMC liners for weight savings.
Damage Tolerance Substantiation and Certification of Multiple Fastener Joints
Authors:   Textron India Private Ltd., Reddy Manjunatha ,   Bell Helicopter, Green W. , Krasnowski Bogdan
Published: October 2024

Damage tolerance (DT) requirements for rotorcraft structures are specified by FAA FAR 29.571 and 29.573 (Ref. 1). In broad terms, DT requires flight critical structure to tolerate certain damage without the damage becoming the source of crack growth and failure. The requirements can apply to multiple fastener joints (MFJ), such as riveted structures widely used in airframe applications, engine mounts, driveshafts, control tubes, etc. (both composite and metallic). Damage in such structures may be benign due to the multiplicity of fasteners to redistribute loads, and multiplicity of holes to stop the growth of damage. DT requirements for metallic MFJ structures are met by analysis of crack growth from the critical hole to failure. Stress intensity factors and material data support this type of analysis (Ref. 2-5). However, traditional analysis neglects the effects of adjacent holes and surrounding structure, which can produce inaccuracies. This paper presents a method for quickly simulating progressive growth of a crack from a rivet hole to an adjacent hole, and beyond. The method is more accurate than traditional methods based on stress intensity factor (SIF) solutions, and much more efficient than finite element methods. A test program was developed to validate the analytical approach, as well as to investigate potential improvements to MFJ designs for damage tolerance and fatigue. The testing employs a crack growth monitoring system that allows detection of multiple crack initiation locations and documentation of crack propagation in a continuous manner, on both sides of the specimen.
A Discrete Crack Network Based Damage Assessment for Bolted Composite Structures
Authors:   Global Engineering and Materials Inc., Lua Jim ,   Naval Air Warefare Center (PAX), Rahman Anisur , Simon Neethi , Fang Eugene , Phan Nam
Published: October 2024

The failure prediction of a bolted joint is complex due to the presence of contact, plastic deformation in the fastener, hole wearing, hole edge crushing, and micro-buckling near the compressive loading zone. In order to capture the mechanism-based failure modes associated with matrix cracking, delamination, fiber breakage, and crushing under a bearing and clamping load, a continuum damage and discrete crack (CDDC) solution module for the Abaqus toolkit is developed where the continuum damage is used to control the damage evolution and energy dissipation and the discrete crack model is used to accurately describe the intensified local stress and strain fields for the subsequent damage evolution prediction. High fidelity discrete damage modeling is demonstrated for a bolted composite lap joint under a static tensile loading. Comparative studies using the continuum damage model (CDM) and CDDC are performed for a filled hole specimen under cyclic tensile loading.
Blade Sections in Streamwise Oscillations into Reverse Flow
Authors:   University of Maryland, Jones Anya ,   Georgia Institute of Technology, Hodara Joachim ,   Universal Technologies Corporation, Granlund Kenneth ,   US Air Force Research Laboratory, Ol Michael , Mulleners Karen , Smith Marilyn
Published: October 2024

A low-Reynolds number rectilinear analog of the retreating blade problem is considered by computationally and experimentally studying a NACA0012 blade in spanwise oscillation in a free stream. Three-dimensional hybrid RANS-LES simulations with spanwise periodic boundary conditions and experimental flow visualization support the description of experimental direct force measurements for a wide range reduced frequencies and advance ratios, including fully reversed flow conditions. A fixed incidence of 6 degrees is taken as a nominally attached-flow case, and agrees reasonably well with Isaacs' theory. A fixed incidence of 20 degrees is taken as a fully-separated case, and departs markedly from inviscid theory, and even more so from quasi-steady approximation. Experimental-computational comparison shows a computational overprediction of lift relative to experimental results, at moderate advance ratios. Agreement in fully reversed flow is, however, quite good.
Full Scale Testing of a Centrifugally Pumped Pneumatic Deicing System for Helicopter Rotor Blades
Authors:   The Pennsylvania State University, Drury Matthew ,   Invercon LLC, Szefi Joseph , Palacios Jose
Published: October 2024

A full-scale centrifugally powered pneumatic deicing system for helicopter blades was developed. The designed system makes use of the pressure differential created within a spinning rotor blade to deform a 0.03 in. (0.762 mm) thick metallic leading edge cap, producing the transverse shear stresses necessary to delaminate accreted ice. Two prototype designs were fabricated and parametrically tested. Both designs consist of a stainless steel leading edge cap tied to the blade surface via flexible stainless steel ribs. The leading edge section is sealed to the blade surface such that it can be pressurized, inflating and deflating as a microvalve is cycled between high and low pressure lines that run along the blade span. Both designs were fabricated and installed on a truncated 12 in. (0.3048 m.) span K-MAX blade section. Icing testing of the prototypes was conducted at The Pennsylvania State University Adverse Environment Rotor Test Stand. Input pressures representative of those produced by centrifugal pressures generated along a full-scale 24 ft. (7.3 m.) radius blade rotating at 270 RPM were provided to the prototypes via a pneumatic slip ring. Parametric testing of the two configurations demonstrated the superiority of one of the designs. The selected configuration was reproduced and installed on the outboard 8 ft. section of a full-scale 24 ft. (7.3 m.) K-MAX blade. Full-scale icing testing was conducted at Kaman’s whirl tower during the month of February. A portable icing cloud generator capable of providing 40 minutes of continuous icing through 12 NASA Standard icing nozzles was developed to provide representative icing conditions. A second cloud generator providing uncontrolled water droplet sizes was also implemented due to power availability limitations to operate the portable icing cloud generation system. The full-scale system was tested at static air temperatures within the Federal Aviation Regulation (FAR) Part 25/29 icing envelope and was able to delaminate ice thicknesses as small as 0.08 in. (2.03 mm.) at 270 RPM.
Twist Effects on Rotor Performance, Loads and Vibrations
Authors:   The Boeing Company, Brouwers Edward ,   US Army Aviation Development Directorate, Centolanza Louis , Zientek Thomas
Published: October 2024

Rotor design is a compromise between hover and cruise flight. A key design variable in rotor design is the twist distribution. New rotorcraft designs require increases in hover efficiency in order to meet demanding future mission requirements. Highly twisted rotors provide improved hover performance however; also generate higher forward flight blade loads, vibratory fixed frame hub loads and ultimately fuselage vibrations. Non-linear tip twist distributions also enable hover performance improvements, but may not suffer the same forward flight loads and vibration penalties as a rotor with a high linear twist rate. In order to quantify these effects and differentiate these two approaches, testing was performed in the Boeing V/STOL Wind Tunnel (BVWT) with three rotor sets. The rotor sets differed only in twist distribution, but had otherwise similar planform, airfoils and property distributions. This paper summarizes the impact of twist on hover and cruise performance, blade loads and fixed frame vibrations on edgewise rotors.
Flight Test Measurement of Ship Airwake Disturbances using Small-Scale Rotorcraft
Authors:   The Pennsylvania State University, Schafer Sylvie ,   Barron Associates Inc., Cooper Jared , Horn Joseph
Published: October 2024

This effort seeks to develop a methodology to identify airwake gust disturbances through flight testing, where identified gust data can be used to validate coupled ship airwake and rotor wake disturbance models used in Virtual Dynamic Interface (VDI) simulations. The gust identification algorithm uses an identified linear model of the aircraft to separate effects of airwake disturbances from responses due to control inputs and to estimate gust velocities. The algorithm only requires standard sensors that are likely to be available on production rotorcraft, i.e. an INS/GPS and measurement of control servo motion. The methodology is initially demonstrated in simulations of a utility helicopter flying in a simulated ship airwake using CFD flow solutions. The flow velocities estimated by the gust identification algorithm are compared to the known flow field properties of the CFD solution, and show reasonable agreement. A sensitivity study is conducted in simulations to quantify the effects of noise and model uncertainty on the accuracy of the gust identification algorithm. Finally, indoor flight tests of a small instrumented RC scale rotorcraft are performed to test the algorithms. This involves system identification tests of the RC aircraft, and flights in simulated gusts while taking simultaneous flow measurements. Initial test results show promise but are inconclusive. Past research has shown this general approach to produce excellent agreement with simulated flight data given an adequately accurate model of the vehicle. The deleterious effects of modeling uncertainty are reported herein which are likely a factor for the non-conclusive flight test results. Limitations on current aircraft instrumentation are a probable cause leading of modeling uncertainty which affects the identified gusts. A motion capture system has been implemented, which might resolve these issues.
Pilot Head and Body Vibration in Response to Main Rotor Track-and-Balance Tuning
Authors:   National Research Council of Canada, Craig G. , Wright-Beatty Heather , Alexander Marc , Keillor Jocelyn
Published: October 2024

While night vision goggles (NVG) have become an essential part of rotorcraft night flight operations for the military, there has been an increase in the reports of neck strain and neck pain in flight crews using the equipment. The neck is required to support the weight of the NVG on the helmet and is constantly stabilizing the head to counteract the helicopter vibrations. The current flight tests examined the magnitude of vibrations at the pilot's head while tuning or slightly de-tuning the track-and-balance of the main rotor on the NRC Bell 412 as well as measuring the physiological response of the pilot to the resulting vibration levels. While the minimal detuning of the main rotor increased the vibration of the helicopter (by about 0.006g), the increase in vibration at the pilots head was substantial (a 0.01g increase). Physiological measures showed increased heart rate and decreased tactile sensitivity as the helicopter vibration increased. While it is likely that the increased vibration resulting from poor rotor track-and-balance increases the level of neck strain on pilots, further research is required to determine the magnitude of these effects and the maximum safe exposure level.
Improving the US Army Rotor Smoothing Algorithm and Coefficient Development Process
Authors:   US Army (Avion Solutions), Hunt James ,   US Army, Bednarczyk Ronald , Ott Douglas
Published: October 2024

Aircraft Rotor Smoothing (aka rotor track and balance) is a complicated process that can be very challenging for even the most experienced maintainers. Rotor smoothing is required to reduce a helicopter's 1/revolution vibration levels. This improves crew comfort and reduces crew fatigue. Maintainers make mechanical adjustments to a rotor system that experiences various dynamic and aerodynamic forces. The typical rotor smoothing event involves balance weight adjustments, pitch link adjustments for changes in blade angle of attack, and blade trailing edge tab adjustments that affect a blade's pitching moment and thus its lift. The rotor smoothing equipment used to determine these adjustments incorporate imbedded empirically developed algorithms and coefficients. It is imperative that these algorithms and coefficients are properly developed. Open lines of communication with aircraft manufacturers are essential due to the differences in aircraft and rotor systems design. The differences in aircraft design may require rotor smoothing methods that are unique to its airframe in order to guarantee successful rotor smoothing events.
Development of a 500 gram Vision-based Autonomous Quadrotor Vehicle Capable of Indoor Navigation
Authors:   Georgia Institute of Technology, Haviland Stephen , Bershadsky Dmitry , Magree Daniel , Johnson Eric
Published: October 2024

This paper presents the work and related research done in preparation for the American Helicopter Society (AHS) Micro Aerial Vehicle (MAV) Student Challenge. The described MAV operates without human interaction in search of a ground target in an open indoor environment. The Georgia Tech Quadrotor-Mini (GTQ-Mini) weighs under 500 grams and was specifically sized to carry a high processing computer. The system platform also consists of a monocular camera, sonar, and an inertial measurement unit (IMU). All processing is done onboard the vehicle using a lightweight powerful computer. A vision navigation system generates vehicle state data and image feature estimates in a vision SLAM formation using a Bierman Thornton extended Kalman Filter (BTEKF). Simulation and flight tests have been performed to show and validate the systems performance.
Single-Shot Pressure-Sensitive Paint Measurements of Static and Dynamic Stall on a Wind Turbine Airfoil
Authors:   The Ohio State University, Disotell Kevin ,   University of Wyoming, Nikoueeyan Pourya , Gregory James , Naughton Jonathan
Published: October 2024

Results of a first application of pressure-sensitive paint (PSP) to a low Reynolds number wind turbine airfoil in static and dynamic stall are reported. Recognizing the need for global surface measurement techniques to resolve the unsteady three-dimensional loading on a moving wind turbine blade, fast-responding PSP was applied to the suction side of a Delft DU97-W-300 airfoil (maximum thickness-to-chord ratio of 30%) at a chord Reynolds number of 225,000 in the University of Wyoming open-return wind tunnel. Static and dynamic stall behaviors are compared using instantaneous and phase-averaged global pressure maps. In particular, a three-dimensional pressure topology resembling a stall cell pattern is prominently observed in static shallow stall. The dynamic stall case was characterized by a sinusoidal pitching motion with mean angle of 15.7°, amplitude of 11.2°, and reduced frequency of 0.106 based on semichord. PSP images were acquired at selected phase positions, capturing the breakdown of nominally two-dimensional flow near lift stall, development of post-stall suction near the trailing edge, and a highly three-dimensional reattachment. By using a laser-based excitation system, the PSP signal was sufficiently strong to capture the dominant surface dynamics under these historically challenging test conditions.
Coupled NS/SPH Analysis of Off-Shore Wind Turbine
Authors:   University of Liverpool, Leble Vladimir , Barakos George
Published: October 2024

This paper presents results of numerical computations for floating off-shore wind turbines (FOWTs) using, as an example, a machine of 10-MW rated power. The aerodynamic loads on the rotor are computed by the Helicopter Multi-Block (HMB2) flow solver developed at University of Liverpool. HMB2 solves the Navier-Stokes equations in integral form using the arbitrary Lagrangian-Eulerian formulation for time-dependent domains with moving boundaries. Hydrodynamic loads on the support platform are computed using the Smoothed Particle Hydrodynamics (SPH) method, which is mesh-free and represents the water and floating structures by a set of discrete elements, referred to as particles. The motion of the FOWT is predicted using a multi-body dynamic model (MBDM) of rigid bodies and frictionless joints. Mooring cables are modelled as a set of springs and dampers. All solvers were validated separately before coupling, and the results are presented in this work. The importance of coupling is assessed and information about coupling algorithms is presented. The loosely coupled algorithm used in present work is described in details alongside the obtained results.
Laser Doppler Velocimeter Measurements in the Ground Interaction Region of an Impinging Scale Model Jet
Authors:   Pennsylvania State University, Hromisin Scott , Rudenko Nicholas , Myers Leighton , McLaughlin Dennis
Published: October 2024

Two-component Laser Doppler Velocimetry measurements were made in the jet plume, impingement region, and outwash region of a scale model jet impinging on a ground plane. The model used for this study is representative of a generic military-style STOVL aircraft in hover. A 13.5mm contoured de Laval nozzle was operated at its design nozzle pressure ratio of 2.93. Velocity measurements were made for ground plate to model separations of 22.9, 12, and 6Dr. Mean velocity measurements in the jet plume and wall jet were compared to previous pitot rake measurements. In general there was good agreement with past data although there was a slight mismatch in measured peak velocities between the two measurement techniques. For plate separations of 12 and 6Dr, axially-directed velocities as high as 250m/s were measured within 0.5Dr of the ground plane. Turbulence intensities as high as 15% of the jet exit velocity were found to be in the shear layer of all jet plumes as well as out to 4Dr in the wall jet for a plate separation of 12Dr. Outwash velocities as high as 25% of the jet exit velocity were found to extend radially out to 7Dr. The decay of peak velocity in the wall jet was found to be approximately inversely proportional to radial position. Spectra obtained for a plate separation of 6Dr showed a distinct tone at several locations in the flow field that agreed well the impingement tone measured previously in the acoustic field. These are large scale motions that have been observed with flow visualizations but have been previously difficult to quantify for supersonic impinging jets.
High-intensity interval training, but not Spirulina supplementation, changes muscle regeneration signaling proteins in aged rats with obesity and diabetes
Authors: Askari Roya , Azarniveh Marzieh Sadat , Haghighi Amir Hossein , Shahrabadi Hadi , Gentil Paulo
Published: October 2024

This study aimed to investigate changes in protein signaling associated with muscle regeneration in aged rats with obesity and diabetes following high-intensity interval training (HIIT) and SP supplementation. Forty male Wistar rats weighting 280-325 g were used in this study. Obesity was induced by eight weeks of a high-fat diet, and diabetes was induced by intraperitoneal injection of 40 mg/kg streptozocin. Rats were randomly divided into control (CON), sham, SP, HIIT, and HIIT+SP groups. HIIT was performed five times per week during the 8-week period. SP dose was 50 mg/kg. Real-time PCR was used to evaluate the expression of myogenin, MyoD1, and Pax7. The decreases in body mass in the HIIT, HIIT+SP and SP groups were significantly higher than those in the sham and CON groups (p=0.0001). The soleus muscle mass increased significantly only in the HIIT and HIIT+SP groups (p<0.01). HIIT+SP improved fasting blood glucose and insulin levels more than HIIT alone and SP (p<0.05), while HIIT increased the expression levels of myogenic factors more than other groups (p=0.0001). In conclusion HIIT alone had a significant impact on myogenic factors, whereas Spirulina had an effect only when combined with HIIT.
Evaluation of the therapeutic potential and safety of Al Hayat black cumin seed oil: an observational study
Authors: Turabekov Bekzhan
Published: October 2024

The purpose of this study was to investigate the therapeutic potential and safety of the use of Al Hayat black cumin seed oil. Descriptive and discrete statistical methods and frequency analysis were applied. There were 20 participants in total aged between 11 and 67 years, both men and women. The participants were divided into three subgroups, each receiving different doses of black cumin oil: 10 mg/kg, 20 mg/kg, and 30 mg/kg, respectively. Such parameters as general blood count, liver enzyme activities (aspartate aminotransferase and alanine aminotransferase), creatinine, and serum iron levels were analysed. A dose of 10 mg/kg was found to have no significant therapeutic or adverse effect. A dosage of 20 mg/kg demonstrated positive effects on platelet, immune cell, and creatinine values with no significant side effects. A dose of 30 mg/kg is not recommended for use due to the high risk of adverse reactions. The author also found no significant differences in the therapeutic effects and adverse reactions to black cumin oil that could be related to the gender or age of the participants.
Biological bases on the concept of hypothalamic-pituitary ‘imprinting
Authors: Barbarino Antonino , De Marinis Laura
Published: October 2024

Endocrine control of genital development and function is exerted by the hypothalamic-pituitary-gonadal axis. The initial signal comes from the hypothalamus which, by secreting a recently isolated and synthesised peptide hormone (GnRH), stimulates the pituitary secretion of the gonadotropins FSH and LH. These in turn control the secretion of gonadal steroids that are different for the male (testosterone of testicular origin) and the female (oestrogen of ovarian origin).
Ethical aspects of the drug addiction problem
Authors: Greco Oronzo
Published: October 2024

The problem of drug addiction among young people is attracting public attention due to the quantitative dimensions of the phenomenon and some of its qualitative connotations.
Prenatal diagnosis and surgical treatment options
Authors: Calisti Alessandro
Published: October 2024

In prenatal diagnostics and its medical, deontological and human implications, the intervention of the paediatric surgeon, that is, the one who has always been involved in the study and treatment of congenital malformative pathology, represents, in many ways, the moment of hope, the moment, in other words, in which it is expected that the diagnostic effort, often onerous on the medical and human level, will result in a concrete therapeutic perspective.
Methodology and ethics in medicine.
Authors: Cattorini Paolo
Published: October 2024

Not available.
Prevalence, risk factors and clinical impact of burnout in internal medicine units: a call to action
Authors: Gnerre Paola , Para Ombretta , Di Massimo Dino Stefano , Attardo Tiziana Marcella , Manfellotto Dario , Dentali Francesco
Published: October 2024

Health workers, and in particular doctors and nurses working in internal medicine units (IMU), are at high risk of burnout. Overcrowding, complexity and severity of clinical cases, patients’ social and family issues, impact of death, and “workload" are all aspects that are specific risk factors that might lead to the development of burnout in this scenario. People suffering from burnout may face several psychological problems (including extreme physical and mental fatigue, emotional exhaustion, loss of enthusiasm concerning work, feelings of cynicism, and a low sense of personal accomplishment) and are also at risk of developing some somatic diseases. Furthermore, the quality of care delivered by a worker in burnout seems to worsen and slip down. In this review, we analyzed the main risk factors and consequences of burnout in IMUs, and we propose individual and organizational measures that may be applied to be able to prevent burnout in this setting.
Utilisation of maternal healthcare services and influencing factors in public health facilities in Addis Ababa, Ethiopia
Authors: Temesgen Sintayehu A. , Netangaheni Thinavhuyo R.
Published: October 2024

Background: Ethiopian maternal mortality remains high, despite the implementation of extensive health programmes. This indicates that the full potential of maternal health services is not being effectively utilised.Aim: This study aimed to evaluate the utilisation and factors influencing maternal healthcare services in public health facilities in Addis Ababa.Setting: This study was conducted in five public hospitals and 10 public health centres of Addis Ababa city administration from 31st August 2023 to 13th October 2023.Methods: The study’s design utilised a cross-sectional quantitative technique, which involved interviewing 354 women from each group who received visits throughout their pregnancy, delivery and postpartum period. The data were analysed using SPSS version 26.Results: This study analysed maternal health service utilisation indicators, revealing a 70.8% overall utilisation of services, with antenatal care (ANC) at 85.5%, delivery at 71.58% and family planning services (PNC) at 55.4%. The study found that the length of time spent travelling to public health facilities significantly impacts the use of maternal health services. Pregnant women who travelled less than 30 min used services 2.29 times more than those over 2 h. The average client wait time also influenced service usage. Pregnant women with four or more prenatal care visits were more likely to use services.Conclusion: The study conducted in Addis Ababa’s capital city revealed that the utilisation of maternity health care services is not optimal, despite the concentrated resources.Contribution: The findings of the study could be beneficial for the Addis Ababa Health Bureau, Ministry of Health, legislators, and other stakeholders. It can help in the development of affordable intervention programmes, filling knowledge gaps and updating scientific understanding.
Detection, Localization of Cardiomegaly and TB Disease of CXR Images using Deep Learning
Authors: P V Ganesh Pradeep , R Dinesh , Paduri Anwesh Reddy , Darapaneni Narayana
Published: October 2024

INTRODUCTION: Tuberculosis (TB) continues to pose a significant worldwide public health concern, as it stands as the primary contributor to mortality stemming from infectious illnesses. Cardiomegaly, characterized by an enlarged heart, poses medical concern as well.OBJECTIVES: Timely identification of Cardiomegaly is vital for effective management. Chest X-ray diagnosis is an easily available method with less radiation exposure to detect several lung infections and heart enlargement. Utilizing computer-aided diagnostic systems can aid in the early detection of lung conditions and the enlargement of the heart.METHODS: We worked on different state-of-the-art CNN architectures such as VGG, DenseNet and EfficientNet with customization over dataset generated from combination of multiple publicly available datasets, which consists of 12939 annotated images across three different categories, one being normal and other two being TB and cardiomegaly diseases..RESULTS: EfficientNetB5 with optimization has shown excellent results amongst others in classifying Tuberculosis and Cardiomegaly with a remarkable accuracy of 97%.CONCLUSION: The proposed model is ready for clinical diagnosis and triaging of X-ray images. Our solution also offers efficient ways to show the presence of the above diseases using Grad-CAM technique.
Detecting Alzheimer’s Patients using Features in Diﬀerential Waveforms of Pupil Light Reﬂex for Chromatic Stimuli
Authors: Nakayama Minoru , Nowak Wioletta , Krecicki Tomasz
Published: October 2024

A procedure to detect irregular signal responses to pupil light reflex (PLR) was developed to detect Alzheimer’s Disease (AD) using a functional data analysis (FDA) technique and classification with an Elastic Net. In considering the differences in features of PLRs between AD and normal control (NC) participants, signals of summations and differentials between experimental conditions were analysed. The coefficient vectors for B-spline basis functions were introduced, and the number of basis was controlled for an optimised model. Model trained data was created using a data extension technique in order to enhance the number of participant observations. In the results, the required number of basis functions for differential signals is larger than the number for the their summation signals, and the features of differential signals contribute to classification performance.
Anderson localization for Schrödinger operators with monotone potentials over circle homeomorphisms
Authors: Kerdboon Jiranan , Zhu Xiaowen
Published: October 2024

In this paper, we prove pure point spectrum for a large class of Schrödinger operators over circle maps with conditions on the rotation number going beyond the Diophantine. More specifically, we develop the scheme to obtain pure point spectrum for Schrödinger operators with monotone bi-Lipschitz potentials over orientation-preserving circle homeomorphisms with Diophantine or weakly Liouville rotation number. The localization is uniform when the coupling constant is large enough.
Topical intranasal anesthesia impairs trigeminal function and airflow perception
Authors: Migneault-Bouchard C , Boselie F J M , Frasnelli J
Published: October 2024

Background: Impairment of airflow perception by the intranasal trigeminal system may explain chronic nasal obstruction (CNO), especially in cases where no major deformity or mucosal inflammation can explain reduced airflow. We aim to characterize the effect of topical intranasal anesthesia on intranasal trigeminal sensitivity and consequently the sensation of nasal obstruction. Methodology: We performed a crossover study of 16 healthy subjects, randomised for either treatment (topical intranasal anesthesia with 10% Xylocaine) or placebo (saline solution). We used the Trigeminal Lateralization Task (TLT) with eucalyptol to assess trigeminal sensitivity. We measured nasal patency objectively with Peak Nasal Inspiratory Flow (PNIF), and subjectively with a Visual Analog Scale (VAS), the Empty Nose Syndrome 6-Item Questionnaire (ENS6Q), and the Nasal Obstruction Symptom Evaluation (NOSE) questionnaire. Results: Topical intranasal anesthesia significantly reduced intranasal trigeminal sensitivity. Further, after topical intranasal anesthesia, reduced trigeminal sensitivity was associated with the subjectively reduced nasal patency, as highlighted by ENS6Q and NOSE scores. Conclusions: Topical intranasal anesthesia reduces intranasal trigeminal function resulting in subjectively reduced nasal patency. In future studies, the relation of reduced intranasal trigeminal function and subjective nasal obstruction needs to be addressed to open an avenue for potential interventions for an important portion of ENT patients.
Mitigating Wire Insulation Damage During Processing and Handling
Authors:   AE-8A Elec Wiring and Fiber Optic Interconnect Sys Install
Published: October 2024

Wire and cable products progress through a series of handling or operational steps from the time they leave the manufacturer, and until a finished harness or assembly is ready for installation on a vehicle. Throughout these many steps, environmental or processing conditions may be present which can generate damage detrimental to the wire or cable and/or its intended application.
Performance-Based Package Standard for Lithium Batteries as Cargo on Aircraft Background Information and Rationales
Authors:   G-27 Lithium Battery Packaging Performance
Published: October 2024

This SAE Aerospace Information Report (AIR) provides additional information and the rationale used for certain elements of AS6413. This AIR is provided to assist persons performing the tests described in AS6413 with an understanding of certain aspects of the test apparatus and the test criteria, such as the volume of the test chamber, cell heating rate, and the pass/fail criteria. It will be updated concurrently with AS6413 to explain changes, provide rationales, and cover future cell/battery technologies as they arise.
Polytetrafluoroethylene (PTFE) Sheet, Molded Premium Grade, As Sintered
Authors:   AMS P Polymeric Materials Committee
Published: October 2024

This specification covers virgin, unfilled polytetrafluoroethylene (PTFE) in the form of sheet manufactured by compression molding and sintering.
Selection and Application of Polytetrafluoroethylene (PTFE) Backup Rings for Hydraulic and Pneumatic Fluid Power Applications
Authors:   A-6C2 Seals Committee
Published: October 2024

This SAE Aerospace Recommended Practice (ARP) provides an overview of the various types of polytetrafluoroethylene (PTFE) backup rings for hydraulic and pneumatic fluid power applications, including their advantages and disadvantages.
Etching of Fluoropolymer Insulations
Authors:   AE-8A Elec Wiring and Fiber Optic Interconnect Sys Install
Published: October 2024

This SAE Aerospace Recommended Practice (ARP) describes the etching of fluoropolymer electrical wire insulations to ensure that all facets of the process from the chemistry to the processing, to the storage and handling are well defined.
Performance-Based Package Standard for Lithium-Ion Cylindrical Cells as Cargo on Aircraft
Authors:   G-27 Lithium Battery Packaging Performance
Published: October 2024

This SAE Aerospace Standard (AS) specifies the testing requirements, including test equipment, to demonstrate a package of lithium-ion (UN3480) cylindrical cells of a format of 21700 or smaller intended for air transport contains the potential hazardous effects to the aircraft resulting from the failure of a cell within the package.

The test described in this standard is intended to force a cylindrical lithium-ion cell into thermal runaway using thermal energy applied to the exterior of a cell. It is understood that, in the future, technology may be developed that will prevent cells from going into thermal runaway by this standard’s test protocol. The scope of this standard may be expanded as more technology and information become available.
On-Board System Requirements for V2V Safety Communications by Non-Light-Duty Vehicles and Motorcycles
Authors:   V2X Core Technical Committee
Published: October 2024

This SAE Standard specifies the system requirements for vehicle-to-vehicle (V2V) safety system for Federal Highway Administration (FHWA) vehicle classes 1 (motorcycles) and 6 through 13 (non-light-duty vehicles), including functional requirements and performance requirements. The system can transmit and receive the SAE J2735-defined Basic Safety Message (BSM) over a wireless communications interface; the communications interface itself is outside the scope of this document. This document provides the specifications necessary to build interoperable systems that support V2V safety applications for non-light-duty vehicles, as well as motorcycles which rely on the exchange of BSMs. The document covers vehicle classes not addressed in SAE J2945/1 and SAE J3161/1.
Conducting online interviews with hard-to-reach hospitality industry participants
Authors: Abdullah Taufik , Carr Neil , Lee Craig
Published: October 2024

Face-to-face interviews have long been a cornerstone of qualitative research methods, yet they can face hindrances, such as long geographical distances and budget limitations for travel to research sites. An alternative solution is the use of online interview techniques. Although studies have discussed issues related to conducting online interviews, challenges in interviewing hard-to-reach participants are still unexplored. In the context of this article, these participants are difficult to reach because they lack the technology required to conduct online interviews and/or their contact information is unavailable. Additionally, there are also issues associated with conducting online interviews that make researchers doubt its ability to produce high-quality data. Based on fieldwork experiences, this research note discusses challenges that occurred during a series of online interviews with hard-to-reach participants in the hospitality industry. This study highlights that even though issues can occur, rich and meaningful data can still be generated from online interviews.