bluuebunny/crossref_metadata_2025 huggingface dataset:
Wind Tunnel Test Results for a 0.2 Scale 4-Bladed Tiltrotor Aeroelastic Model
Authors:   Bell Helicopter Textron Inc., Newman Jeff , Parham Tom , Johnson Casey , Popelka David
Published: October 2024

A 0.2 scale 4-bladed stiff inplane tiltrotor aeroelastic model was tested at the NASA Langley Transonic Dynamics Tunnel (TDT) in October and November 2011. This aeroelastic model included a novel stepover control mechanism designed to improve whirl flutter stability boundaries for a 4-bladed tiltrotor. The stepover control mechanism provides the rotor kinematic control coupling necessary for stability but is designed to fit within the limited space of a 4-bladed rotor hub. Airplane mode stability boundaries with and without the stepover control mechanism installed were measured during the wind tunnel test. Stability test results show that the stepover mechanism provides as much or more stability to the 4-bladed rotor as the conventional control system provided for the 3-bladed rotor. With the stepover control mechanism removed (i.e. reverting to a conventional control system design), the 4-bladed configuration was found to be unstable at significantly lower airspeeds. In addition, a GPC (Generalized Predictive Controller) active stability control algorithm was tested and shown to significantly increase the subcritical damping of the 4-bladed aeroelastic model with a conventional control system installed. Rotor loads and vibrations were measured at various nacelle angles and trim conditions. For direct comparison with the 4-bladed rotor, rotor loads were also measured on a 0.2 scale 3-bladed V-22 rotor. Differences in the dynamic behavior and loads of the two rotor configurations are explored.
Blade Property Measurement and Its Assessment on Air/Structural Loads of HART II Rotor
Authors:   NASA Ames Research Center, Hagerty Brandon ,   DLR - German Aerospace Center, Riemenschneider Johannes ,   Konkuk University, Jung Sung , Keimer Ralf , You Young-Hyun , Dhadwal Manoj
Published: October 2024

In this study, the structural properties of Higher-harmonic Aeroacoustic Rotor Test (HART) II blades are determined using the state-of-the-art test techniques. The measurement includes bending and torsion stiffnesses, section geometric offsets, and mass and inertia properties. Several HART II blades including the original instrumented blade used for the wind tunnel test campaign in 2001 are employed for the activity. A finite element based cross-section analysis combined with the x-ray computer tomography (CT) technique is employed for the cases where no mechanical measurement is available or attempted. The resulting structural properties are correlated against the earlier estimated values which have extensively been used in the literature for the validation of HART II rotor. It is found that the earlier blade properties overestimate the section values substantially. The comprehensive rotor dynamics analysis is performed to quantify the impact of the measured blade properties on the aeroelastic behavior of the rotor. The location of center of gravity is demonstrated to be the most influential factor affecting the correlation and also the sensitivity of the aeromechanics behavior of the rotor.
Control Loads Reduction Through Control System Architecture Optimization - Application to a Conventional Rotor on a Compound Helicopter
Authors:   Airbus Helicopters, Paris Manuel ,   LSIS, Malburet Francois , Eglin Paul , Carmona Jean-Claude
Published: October 2024

A kinematic study of a helicopter main rotor control system is carried out to investigate loads in servo actuators and non-rotating scissors during high speed and high load factor maneuvers. The kinematic model is then used to optimize the servo-actuators placement and pre-inclination in order to minimize static and dynamic loads in the three servo-actuators and in the non-rotating scissors. The inputs for the model (blade pitch link loads and pilot input to trim the aircraft) are taken from flight tests measurements, current rotor computations being unable to predict blade root torsion moments vs azimuth with enough accuracy. The analysis is based on X3 demonstrator flight tests, which showed high control system loads that used to reduce flight envelope during the first flight test campaign. Flight tests measurements are used to validate the kinematic model used for the optimization. Computations made for X3 case at 220kts showed a reduction of 40% of maximum static load and 45% of maximum dynamic load on servo-actuators compared to the initial placement of the servo actuators. With appropriate servo actuators pre-inclination, dynamic loads in the non-rotating scissors are decreased by 95% at high speed trim flight. This paper shows how it is possible to keep a conventional rotor control system for compound helicopters. The optimization algorithm presented in this paper can be used for conventional helicopters to reduce loads in the control system and then limit command reinjection because of control system flexibility, and on compound helicopters to expand the flight envelope and to remove control system loads as the first limit factors at high speed.
Advanced Beam Modeling Applied to Articulated Rotor - Implementation in HOST Aeromechanic Simulation Tool
Authors:   Airbus Helicopters, Skladanek Yan , Boucherie Laurent , Benoit Bernard , Cranga Paul
Published: October 2024

Advanced beam modeling is one of the main research topics for Rotorcraft Comprehensive Analysis (RCA) simulation tools enhancement. HOST is the aeromechanic code developed by AIRBUS HELICOPTERS over the last 25 years and it is continuously upgraded to fit to the new needs. To study the most recent evolutions of rotors and blades (such as Blue Edge™ blades) new modeling strategies must be foreseen including an advanced model featuring all geometric and coupling effects of beam in centrifugal environment and a global modeling approach within the RCA software hosting all the simulation tools required for aircraft development. In this scope Airbus Helicopters has launched the development of Beam Advance Model (BAM) and its integration in HOST. After a short recall of BAM theoretical basis, this paper discusses the implementation strategy chosen for such an advanced model, presents the validation of the method and provides the first available results coming from a full integrated trim calculation on articulated rotor. Dynamic results on Blue Edge™ blade whirl tower test demonstrate the relevancy of BAM model while the validation of its implementation in HOST is presented on full-scale straight bladed rotors.
A Parametric Study of On-Blade Control Device Performance for Helicopter Vibration and Noise Reduction
Authors:   University of Michigan, Padthe Ashwani , Friedman Peretz , Chia Miang
Published: October 2024

The effects of rotor blade stiffness on the vibration and noise reduction performance of a 20%c plain trailing edge flap and a 1.5%c sliding microflap are studied under heavy BVI conditions in descending fight at μ = 0.15. The adaptive Higher Harmonic Control (HHC) algorithm is used on a hingeless rotor configuration resembling the MBB BO-105. The performance of the on-blade control devices is studied for a range of blade torsional frequencies. The effect of varying spanwise location of on-blade control devices and the chordwise placement of the microflap are studied. A torsional frequency of 3.17/rev is optimal for most configurations. Nevertheless, vibration reduction of 90% is achieved at the highest torsional frequency of 8/rev using a dual plain flap configuration. Noise reduction performance is more sensitive to changes in the torsional frequency. The on-blade control devices are less effective at torsional frequencies above the optimal value.
Investigation of RCAS--CAMRAD II UH60 Structural Dynamics Model Correlation
Authors:   American Society for Engineering Education, Silbaugh Benjamin ,   US Army Research Lab, Kang Hao , Floros Matthew , Singh Rajneesh
Published: October 2024

The correlation between RCAS and CAMRAD II structural dynamics modeling for the UH60 rotor is investigated. This is important, as both RCAS and CAMRAD II are used extensively by Industry and Government for rotorcraft research and product evaluation. Equivalent RCAS and CAMRAD II UH60 models are subjected to a series of in vacuo rotor tests and blade deformations are compared. Discrepancies between pitch displacements and lag displacements are observed. A series of diagnostic tests are run to isolate the cause of these discrepancies. The results of the diagnostic tests suggest that the pitch angle discrepancy is related to treatment of axial-torsion coupling, and the lag discrepancy is related to modeling of the control system. Some notes regarding proper usage and setup of RCAS and CAMRAD II are also provided.
A Portable Display for Evaluating Handling Qualities in Shipboard Hover
Authors:   Mitchell Aerospace Research, Mitchell Dave ,   US Navy (NAVAIR), Roark Sean , Molinaro Gino
Published: October 2024

A limited flight test assessment of a portable display for evaluating handling qualities in shipboard hover was performed. The Portable Optical Navigation Guidance (PONG) display is intended as a land-based component for replicating the control motions required for hovering over the deck of a small ship. It is based on the Canadian National Research Council's Flight Research Laboratory's Superslide display. A U.S. Marine Corps fleet-configured Bell UH-1N, used by the U.S. Naval Air Warfare Center's Naval Aviation Center for Rotorcraft Advancement organization, was flown by three pilots, all with recent shipboard experience, to assess the fidelity of PONG for varying forcing function intensity levels (Sea States). In this limited assessment, the pilots' comments about PONG were generally not as favorable as those given by other pilots for the NRC's Superslide. While the flight program did not provide an opportunity to identify the differences in configurations, possible reasons for the differences in pilot opinion are discussed.
UH-60 Partial Authority Modernized Control Laws for Improved Handling Qualities in the Degraded Visual Environment
Authors:   US Army Aviation Development Directorate - AFDD, Fujizawa Brian , Tischler Mark , Ott Carl , Blanken Chris
Published: October 2024

The U.S. Army's helicopter fleet consists chiefly of aircraft developed in the 1960's and 1970's with flight control systems based on the requirements of that time. Since then, Army helicopter operations have changed from predominantly daytime, good visual environment (GVE) operations to night and degraded visual environment (DVE) operations. Rotorcraft handling qualities and flight control requirements did not address DVE operations until the introduction of ADS-33 in 1985. Numerous attempts to improve the handling qualities of rotorcraft in the DVE through flight control upgrades have been studied with the CH-47F DAFCS representing a successful partial-authority solution. In 2000, AFDD and Sikorsky developed the UH-60 Modernized Control Laws (MCLAWS) which were intended to satisfy the ADS-33 DVE requirements using the existing limited-authority actuators. While the original program ended in 2003, the effort was resumed at AFDD in 2012 with numerous improvements incorporated into the MCLAWS. Flight tests in brownout conditions at Yuma Proving Ground demonstrated that the MCLAWS resulted in reduced the pilot workload when compared to the legacy UH-60 SAS/FPS control system. A handling qualities evaluation conducted at Moffett Field in simulated DVE conditions on five ADS-33 mission task elements demonstrated Level 1 handling qualities.
Seeded-Fault Spin-Testing of an Active Rotor Electromechanical Actuator and Mechanism
Authors:   United Technologies Research Center, Matalanis Claude ,   UTC Aerospace Systems, Brewer Paul , Kuczek Andrzej , Jonsson Ulf , Wake Brian , Kim Seung , Chaudhry Zaffir
Published: October 2024

Seeded-fault spin-test results are presented on a representative active rotor system equipped with a prognostics and health management (PHM) sensor suite. Backlash in the mechanism and faults associated with the high-authority electromechanical actuator used to drive the system are investigated. The sensor arrangement used shows the ability to detect and potentially estimate the extent of mechanical backlash at nearly any point in the mechanism. The actuator sensor suite showed the ability to detect multiple independent faults associated with loss of oil, the presence of metallic debris, and oil contamination/ discoloration. The PHM strategy employed on this test article involved a fairly large number of sensors. The results from this study suggest a more optimal strategy whereby the number of sensors can be reduced while maintaining the ability to detect the faults mentioned above.
Propulsion System Diagnostic and Reasoning Technology Development
Authors:   Sikorsky Aircraft Corporation, LeFevre Brian ,   US Army Aviation Development Directorate, Baker Treven , Friel Jason , Mackos Nicholos
Published: October 2024

The Sikorsky Aircraft Corporation (SAC) and the U.S. Army Aviation Development Directorate (ADD) Aviation Applied Technology Directorate (AATD) are jointly sponsoring the Capability-Based Operations and Sustainment Technology-Aviation (COST-A) project. The objective of COST-A is to demonstrate an integrated set of high-value diagnostics, prognostics, and system health management technologies that reduce the maintenance burden imposed by the Army's rotorcraft fleet, while at the same time preserving safety and reliability. The program was divided into six different primary technical focus areas, with the propulsion system being one of those areas. The primary goal of the COST-A propulsion effort is to develop a robust set of diagnostic and prognostic algorithms that provide insight into the health of key components of a rotorcraft's propulsion system including the main engines and various critical Line Replaceable Units (LRUs). Separate diagnostic algorithms have been developed for key main engine LRUs such as the Hydro-Mechanical Unit (HMU), Anti-Ice / Start Bleed Valve (AISBV), Inlet Particle Separator (IPS) blower, pneumatic starter, and cross-bleed valves. Other diagnostic and prognostic algorithms have been developed or refined that focus on assessing the gas path health of the engine as a whole and of each of its major modules (gas generator and power turbine), and assessing sensor quality to identify biases. In addition, the Auxiliary Power Unit (APU) is the target of both gas path health and sensor quality diagnostics. Information from all of these algorithms is fused using a series of reasoning algorithms which translate condition indicator (CI) data into actionable information for maintenance decision support. In this paper, several of the aforementioned COST-A Propulsion technologies will be discussed in detail and an example failure scenario will be utilized to elaborate diagnostic and reasoner functionality.
Optimal Design of Compound Helicopters Using Higher Harmonic Control
Authors:   Duke University, Giovanetti Eli , Hall Kenneth
Published: October 2024

We investigate the optimal design of a compound helicopter comprised of counter-rotating coaxial rotors, a propeller, and optionally a fixed wing. We determine the blade geometry, azimuthal blade pitch inputs, optimal shaft angle (rotor angle of attack), and division of propulsive and lifting forces among the components that minimize the total power for a given flight condition. The optimal design problem is cast as a variational statement that minimizes the sum of induced and viscous power losses for a prescribed lift, propulsive force, and vehicle trim condition. The rotor, propeller, and wing geometry and control inputs are related to the far-field circulation through a lifting line model that accounts for experimentally or computationally determined nonlinear lift and drag polars. The variational statement is discretized using a vortex lattice wake, and the resulting nonlinear constrained optimization problem is solved via Newton iteration. We show that varying the prescribed propulsive force of the system affects the optimal shaft angle and rotor design, and that higher harmonic control reduces total vehicle power loss (inefficiency) in high speed flight by as much as 15 percent. We also show that imposing a maximum allowable lateral lift offset can greatly increase the power loss of the coaxial rotors.
Study of Processing Conditions on the Forming of Ribbed Features Using Randomly-Oriented Strands Thermoplastic Composites
Authors:   McGill University, LeBlanc Dominic ,   Bell Helicopter Textron Canada, Quinlan Erin ,   National Research Council Canada, Roy Steven , Landry Benoit , Levy Arthur , Hubert Pascal , Yousefpour Ali
Published: October 2024

Compression moulding of randomly-oriented strands composites offer the possibility to manufacture complex parts with fast processing cycle. In this paper, effects of pressure, strand size, temperature and material placement in the mould cavity on the quality of a T-shape part were studied experimentally. Low pressure results showed both strand size and temperature effects on the filling of a 25 mm rib deep cavity. Critical filling pressures for three strand sizes were obtained. A pressure of 10 bar was enough to fully consolidate parts with smaller strand (3.17 mm × 6.35 mm) at 400 °C. Parts processed at filling pressure showed a void content no greater than 1.2 %. Increasing pressure to 70 bar resulted in decreased void content between 0.44 % and 0.03 %. The lowest void content was obtained for parts processed at lower temperature. Short-beam shear (ASTM D2344) showed similar strength for ribs processed at filling pressure and high pressure (70 bar). This same trend was observed for component testing of the T-shape. At the component level, initial strand placement greatly affected mechanical performance as merging flow fronts caused a knit line and a reduction of at most 40 % in strength. The main findings show that processing a complex feature at filling pressure Pfill was sufficient to reach nominal mechanical properties. This suggested that moderate porosity was not detrimental to the mechanical performance for the given tests.
Improving the Predictions of Distortions Throughout the Manufacturing Process of Mechanical Parts for a "One Shot" Industrialization
Authors:   Airbus Helicopters, Looze Jean-Bertrand ,   Airbus Helicopters Subcontractor, Caula Tiffany , Himbert Nolwenn , Durand Philippe , Feraille Julien , Taillandier Marc , Struzik Alain
Published: October 2024

The high quality design requirements in Airbus Helicopters (AH) dynamic Systems make the mechanical parts more and more complex to manufacture. In order to avoid long cycle and expensive manufacturing development, it is necessary to anticipate the process risks, such as part distortions throughout the manufacturing line. In this work, the predictions of distortions by simulations of different manufacturing processes have been carried out. As a first step, the simulation of a quenching / tempering heat treatment followed by material removal was performed on a helicopter gear in 32CDV13 low alloyed steel using the Sysweld™ software. Numerical results and the experimental measurements of stresses were compared. In addition, a simulation of a rotating swashplate shrinking in aluminum alloy was carried out on the Samcef software. Preliminary numerical results were promising. Similar comparison studies are still needed to validate the software and some developments are also planned for a future full manufacturing line simulation.
Comparison of Simulator Platform and Flight Tasks on Adverse Rotorcraft Pilot Coupling Prediction
Authors:   Technical University of Delft, Yilmaz Deniz ,   University of Liverpool, lu linghai , Pavel Marilena , Jump Michael , Jones Michael
Published: October 2024

Previous investigators have found that obtaining the same results using different simulation facilities for notionally identical test can be difficult to achieve. This was also found to be true in the EC-Framework 7-funded ARISTOTEL project. This project used two simulators in parallel - the HELIFLIGHT-R Simulator (HFR) at the University of Liverpool and SIMONA Research Simulator (SRS) at TU Delft in a study aimed at creating tools and techniques to predict, detect and eliminate rotorcraft pilot couplings (RPCs). Therefore, an essential part of the investigation was to understand the effect of using these two simulator platforms on the ability of pilots to detect rotorcraft pilot couplings (RPC). Similarity between the two facilities was verified both objectively and subjectively for three key simulation components: the open-loop aircraft flight dynamics model, the visual display system and the motion drive system. The closed-loop pilot-awarded subjective visual and motion cueing ratings indicated that the two simulators had reached a good level of similarity for the latter two of these items. Inspection of non-linear responses to pre-defined control inputs showed the same for the aircraft model. Pilot-in-the-loop flight simulation test campaigns were conducted on four ADS-33E-PRF maneuvers: Acceleration-Deceleration, Vertical Maneuver, Hover Maneuver, and Roll Step. The data obtained was analyzed in terms of subjective Handling Qualities Ratings and Pilot-Induced-Oscillation Susceptibility Ratings and objectively using the pilot cutoff frequency. It was found that the ratings obtained using SRS were generally higher than the corresponding data from HFR. An explanation for this finding was provided by using a modified time-varying power frequency metric to distinguish pilot control activities in the frequency domain between the two simulators. Pilots in SRS generally have higher stick activity intensity than when flying in HFR. The subjective and quantitative results show that SRS appears to provide a more RPC-susceptible environment than HFR and this appears to be due to its slightly lower resolution visual environment when compared to HFR.
Airframe Active Vibration-Based Damage Detection and Localization
Authors:   The Pennsylvania State University, Long Justin ,   Applied Research Laboratory, Conlon Stephen
Published: October 2024

The development of damage detection, localization and automation techniques is crucial for the successful integration of structural health monitoring technologies in rotorcraft. This study focused on the development of a nonlinear vibration spectroscopy based damage detection and localization method. A progression of damaged joint conditions was created in a prototypical stiffened aluminum plate test bed. Active vibration sources were used to excite the structure, and strain sensor rosettes were used to measure the nonlinear vibration responses induced by the damage. Using a systematic approach, response strain amplitudes were processed at the nonlinear frequency components, and the position of the damage was estimated based on maximum principal strain angle calculations from three strain rosette nodes. Accurate damage localization results were obtained for each damage condition, using relatively low force levels. Effective high frequency excitation for each localization result depended on the damage size and damping present in the system. Edge damping and losses due to sound radiation appeared to affect the localization scheme by reducing energy transmission at some frequencies, as well as reflections from the boundaries. Using developed data processing and automation routines, the technique showed promise for translation to real airframe structures.
Bell 412EPI Engine and Glass Cockpit Upgrade
Authors:   Bell Helicopter, Schillings John , Oltheten Erik , Greenwood Jeff , Thomas BJ , Runge Hans , Sowers Dale
Published: October 2024

This paper introduces the Bell 412EPI engine and glass cockpit upgrade. Design features of the Pratt and Whitney Canada (P&WC) PT6T-9 Twin Pac® and the Bell BasiX-Pro® Integrated Avionics System are described. The certification approach, aircraft development, and flight testing are discussed. Procedures and flight profiles for Category A takeoffs are shown for three types of surfaces, Ground Level Helipad, Elevated Helipad, and Runway. Example time histories of measured data are presented for Rejected Takeoffs and Completed Takeoff maneuvers. Hover and Category A performance data are shown, and comparisons are made to the baseline Bell 412EP. A fifteen percent increase in hot day takeoff power available results in increased hover capability. New 30-second OEI, 2-minute OEI, and Continuous OEI ratings provide substantial increases in Category A gross weight capability.
Flight Testing of an In-Flight Tuning System on a CH-53G Helicopter
Authors:   ZF Luftfahrttechnik GmbH, Arnold Uwe , Fuerst Daniel , Hausberg André , Hartmann Steffen
Published: October 2024

In-Flight Tuning (IFT) can be realized by a set of so-called Smart Pitch Rods (SPR™) which replace the conventional fixed-length pitch links. Electrically driven and digitally controlled by a corresponding "IFT commander", the length of each pitch link can individually be changed during the flight. Thereby, the RT&B process can considerably be simplified and the blade pitch settings can continuously be optimized depending on the actual flight condition. ZFL was contracted to develop, fabricate and flight test such IFT system on a CH-53G testbed of the German Armed Forces. This paper gives a brief overview of the system architecture, the chosen safety concept and the aircraft integration. Then, the major qualification and certification steps from component to system level are summarized. The main part discusses the results from the first 20+ flight hours of dedicated IFT flight testing. This covers flights with open loop and closed loop control, partly with the main rotor intentionally "detuned" as well as test cases with simulated sudden changes of the blade properties. Finally, some results from maneuver flights with the IFT system kept active are presented. All flights have shown the flawless and safe operation of the system. The tests have proven the capability not only to streamline the initial RT&B procedure but also to optimize the vibratory condition of the rotorcraft across the complete flight envelope and for different operating conditions through the continuous and automatic re-adjustment of the pitch settings.
Benchmarking of UAV Guidance Systems in Nap of the Earth (NOE) Flight
Authors:   Georgia Institute of Technology, Bershadsky Dmitry , Johnson Eric
Published: October 2024

This paper describes the development of a proposed framework of metrics for the evaluation of the performance of aircraft guidance systems. The methodologies and metrics developed remain generally agnostic to whether or not the aircraft is manned. Although more complicated missions such as autonomous exploration/search, ferry, surveillance, multi-agent collaboration, and manned flight may be addressed at a later time, A-B flight scenarios are chosen to study the proposed metrics. The proposed metrics will form building blocks for the more complicated missions. Metrics development has thus far generally focused on NOE flight, and in particular on the observability of the vehicle throughout its mission. That is, a formulation of probability of detection by potential and generally unknown threats in the mission area will be the main metric. Secondary metrics provide insight into the vehicle's trajectory quality in terms of safety and comfort, experienced by both humans and machines are described as well. Scalability of the benchmarking system is also important and benchmarking should be general enough to allow guidance algorithms to be graded independently of the vehicle platform, for instance. Non-dimensionalization metrics will address this concern.
Collaborative Search and Pursuit for Autonomous Helicopters
Authors:   Georgia Institute of Technology, Mooney John , Johnson Eric
Published: October 2024

This paper describes recent results from the Georgia Institute of Technology to develop, improve, and flight test a multi-aircraft collaborative architecture, focused on decentralized autonomous decision-making. The architecture includes a search coverage algorithm, behavior estimation, and a pursuit algorithm designed to solve a scenario-driven challenge problem. The architecture was implemented on a pair of Yamaha RMAX helicopters outfitted with modular avionics, as well as an associated set of simulation tools. Simulation and flight test results for single- and multiple-aircraft scenarios are presented. Further work suggested includes identification and development of more sophisticated methods that can replace the simpler elements in modular fashion.
Design Space Exploration of Gyrocopter-Type Airborne Wind Turbines
Authors:   Georgia Institute of Technology, Rancourt David , Teasdale François , Bouchard Etienne , Anderson Michael , Mavris Dimitri
Published: October 2024

This paper presents a design space exploration of gyrocopter-type airbone wind turbines through a multidisciplinary analysis and optimization (MDAO) environment, and provides guidelines for future development of this novel concept. Four rotary wings provide lift to a flying vehicle and excess power is extracted using gearboxes and generators before being transferred to the ground through electrical conductors embedded in a structural tether. A physical breakdown of the system was performed and five models were constructed: wind model, rotor aerodynamics, structural mass, electrical system and tether (structures and aerodynamics). An optimizer was then used to ensure interdisciplinary compatibility and maximize electrical power transmitted to the ground under various operating conditions. The effect of implementing new technologies was also studied in order to evaluate their effect on the overall performance of the system. Finally, it is shown through a 1.3 MW design that a gyrocopter-type airborne generator could provide more power than a ground based wind turbine for a given blade radius, although only a fraction of the available wind power can be harvested using off-the-shelf technologies and components.
Evaluating Sustainability in Social-ecological Systems: 50 Years of Conservation in Florianópolis, Brazil
Authors: Bridges Allison
Published: October 2024

This study examines 50 years of land use planning practices in Florianópolis, Brazil, to identify the attributes that resulted in the city’s notable and long-standing commitment to pro-conservation programmes and policies. By analysing key policies, planning strategies, and partnerships that underpin the preservation of forests and green spaces, this research contributes valuable insights to the ongoing discourse on the combined role of conservation governance and collective action in building sustainable and resilient cities. The social-ecological systems framework is applied to evaluate the interactions between multi-level laws, collective action groups, and mid-level government officials to determine the drivers that promoted incremental and accumulative change, ultimately leading to sustainable land conservation practices in Florianópolis. The findings highlight the importance of stakeholder goal alignment, managerial flexibility, and collaboration with diverse actors in achieving long-term conservation goals, particularly in cities adopting an amenity-led growth model. Growing challenges to the continued protection of conservation units in the city resulting from population growth are also raised to advance approaches to evaluating the durability of sustainability initiatives.
Efficacy of Pharmacological Treatments in Managing Generalized Anxiety Disorder among Adults in Saudi Arabia: A Cross-sectional Analysis
Authors: Aleid Abdulsalam Mohammed , Alharthi Abdulaziz Matar , Alotaibi Rana Abdulmohsen , Alasmari Ahmed Mohammed , Alzabdawi Sharifah Ahmed , Asaeed Imtinan Jafar , Alshuqayfi Sarah Mousa , Alzahuf Shuruq Mohammed , Alharthi Aliyah Matar , Alhodibi Mostafa Habeeb
Published: October 2024

Introduction:

Generalized anxiety disorder (GAD) is a significant mental health concern characterized by excessive and uncontrollable worry about everyday activities. Despite its prevalence, there is a scarcity of research on pharmacological management strategies for GAD, particularly within the Saudi Arabian context. This study aims to address this gap by identifying and evaluating the most commonly used pharmacological strategies among adults in Saudi Arabia. It will assess the effectiveness of these strategies, examine factors influencing the preference of these strategies, and explore the prevalence and impact of adverse effects associated with them.

Methods:

This cross-sectional study employed stratified random sampling to select a representative sample of adults aged 18 years and above from various regions of Saudi Arabia. Participants provided data through self-administered questionnaires, which included information on sociodemographic characteristics, GAD symptoms, pharmacological strategies utilized, their effectiveness, and any adverse effects. The study’s analytical approach encompassed statistical methods such as correlation, regression, and Chi-square tests, aiming to uncover relationships and patterns among the collected data, particularly focusing on treatment efficacy and the occurrence of adverse effects.

Results:

We found a demographic skewing among Saudi patients with GAD, particularly toward young adults aged 18–24 and women. The majority of these patients were diagnosed with GAD and had been experiencing symptoms for less than six months. In addition, there was a notable willingness among them to seek professional help. The most commonly used pharmacological strategy was classified as “Others,” with a high satisfaction rate reported by users. Adverse effects were infrequent, affecting only a minority of patients frequently. Selective serotonin reuptake inhibitors demonstrated the highest mean improvement in GAD symptoms, indicating their effectiveness. Our study also emphasized the importance of considering medication side effects, especially for individuals with a greater tendency to adverse events.

Conclusion:

This research emphasizes the importance of personalized treatment plans, medication efficacy, and side effect profiles for managing GAD in Saudi Arabia. It also underscores the need for evidence-based treatment guidelines and suggests areas for future research to optimize GAD treatment strategies based on individual patient needs and therapy responses.
Analysis of Parental Stress and Anxiety Symptoms during COVID-19 Pandemic in Khulna City
Authors: Tasfiya Nuzhat , Islam Tanjirul , Haider Ali , Turzo Noor A. Alom , Al Hassan Sakib , UL Husna Asma
Published: October 2024

Introduction:

The COVID-19 pandemic tremendously increases mental health risk among parents due to extreme anxiety and stress. This study focuses on examining the variables related to parental stress and anxiety amid the COVID-19 epidemic.

Methods:

A cross-sectional survey was conducted among 118 parents in three wards (18, 27, and 28) of Khulna city, Bangladesh. Parental stress and anxiety during the COVID-19 pandemic were measured using the GAD-7 and PSS-10 scales. Socioeconomic and demographic data were also collected from households. The association between stress and anxiety and their contributing factors was analyzed using the Chi-square test and binary logistic regression.

Results:

The results showed that 27.5% of parents aged over 40 years and 35.6% of those who faced unemployment during COVID-19 experienced severe stress and anxiety. The regression analysis results confirmed this result. Furthermore, educational status, type of family, marital status, and total household income were found to be significant factors affecting parental stress and anxiety symptoms. The study demonstrated a significant impact of COVID-19 on elderly parents.

Conclusions:

These findings suggest that COVID-19 has significantly impacted elderly parents. Therefore, the study highlights an urgent need for mental health support to assist this vulnerable group in urban areas of Bangladesh.
A Clinicodemographic Study of Indian Patients with Hidradenitis Suppurativa and its Association with Metabolic Syndrome
Authors: De Dipankar , Baskaran Narayanan , Thakur Vishal , Hanumanthu Vinod H. , Bakshi Shirin , Bhandari Sudhir , Katoch Deeksha , Handa Sanjeev
Published: October 2024

Background:

Hidradenitis suppurativa (HS) is a chronic inflammatory disorder affecting pilosebaceous units causing painful nodules, abscesses, and scarring. Despite global studies linking HS to metabolic syndrome, insights specific to Indian patients are limited.

Materials and Methods:

This study aimed to describe the clinicodemographic characteristics and study frequency of metabolic syndrome in Indian HS patients. In this cross-sectional study, 100 HS patients were evaluated for clinical characteristics, comorbidities, pain and suppuration scores, quality of life, and ophthalmological and dental abnormalities. Metabolic parameters, including anthropometry and blood markers, were performed in all cases and 100 age- and gender-matched controls.

Results:

The mean age was 29.47 years, with a male predominance of 57%. HS predominantly affected a combination of two or more sites (60%), with nodules as primary lesions (95%). Quality of life was significantly impaired, with 49% experiencing moderate impact as per Dermatology Life Quality Index. Metabolic derangements, represented by an increased body mass index, waist circumference, blood pressure, fasting blood sugar, and fasting insulin, were significantly more frequent in HS cases compared to controls (P < 0.001). The frequency of metabolic syndrome in HS patients was 42%, significantly higher than controls (8%, P < 0.001) with a relative risk of 5.25 (95% CI 2.68–10.58). Dental and ophthalmological abnormalities were observed in 35% and 21.7% of screened patients, respectively.

Limitations:

Cross-sectional nature, no prospective assessment to determine evolution with time, and limited patient number are the limitations of the study.

Conclusion:

A substantial association with metabolic syndrome and considerable impact on quality of life is seen in Indian HS patients, emphasizing the need for metabolic screening and holistic management strategies.
Colposcopy Scoring Systems
Authors: Parveen Nazia , Gupta Bindiya
Published: October 2024

Colposcopy is the essential diagnostic tool needed to examine the cervix of women with abnormal cervical cytology or high-risk human papillomavirus and abnormal-appearing vaginal or cervical tissue. Various scoring systems have been recommended in order to improve the accuracy of colposcopic impression. Reid’s Colposcopy Index, Swede score, International Federation of Cervical Pathology and Colposcopy 2011, and most recently American Society for Colposcopy and Cervical Pathology (ASCCP) 2017 have been introduced and management recommendations for cervical screening are formulated. The new consensus ASCCP 2017 guidelines follow a risk-based approach rather than a result-based approach to determine the need for colposcopy, surveillance, and management.
Breast Cancer Screening: Guidelines and Opportunities for Gynecologists
Authors: Nigam Aruna , Singhal Neeti
Published: October 2024

Breast cancer is the most common cancer worldwide and is the leading cause of deaths from cancer among women. It accounts for 12% of all cancer cases worldwide and 39.4% of the total cancer cases in women in India. The number is expected to rise to more than 2.3 lakh cases by the year 2025. As a general instinct, females usually come to gynecologists with problems related to breasts apart from other gynecological problems. Hence, they play a vital role in early detection by identifying the high-risk patients, screening them and spreading awareness. Risk factors for each age group should be identified and guidelines for screening must be followed. Breast selfexamination should be promoted and awareness regarding it should be spread as it can detect almost 90% of breast cancers. Clinical breast assessment skills should be developed and mammography should be encouraged.
Comparison of Conventional Pap Smear With Liquid-based Cytology for Screening of Cancer Cervix
Authors: Kaur Guneet , Zutshi Vijay , Priya M. Lekshmi , Yadav Amit
Published: October 2024

Objective:

The objective of the study was to compare conventional Pap smear (CPS) and liquid-based cytology (LBC) by the split technique method in terms of satisfactory/unsatisfactory smear, the prevalence of inflammatory smear, and cellular atypia.

Materials and Methods:

This cross-sectional study was carried out between 2017 and 2019 after obtaining ethics committee approval. A total of 200 women were recruited for the study attending the gynecology outpatient clinic with various symptoms, such as discharge per vaginum, dysmenorrhea, infertility, and pain abdomen, and after obtaining written informed consent. Pregnant women, women with pelvic inflammatory disease, and cases with obvious cervical lesions or growth were excluded. Pap smear was taken with a Rovers Cervex-Brush. The split sample technique was followed wherein using one side of the brush conventional slide was prepared and fixed with cytospray. The brush head was detached and suspended in the preservative fluid for LBC. Both CPS and LBC were sent for examination. The same experienced pathologist examined the samples. The qualitative variables were compared using the Mcnamer test to compare the prevalence of unsatisfactory smear, inflammatory smear, and cellular abnormalities between CP and LBC. The categorical variables were presented in number and percentage (%) and continuous variables were presented as mean ± standard deviation and median. P < 0.05 was considered statistically significant.

Results:

The maximum number of patients (62.5%) belonged to the fourth decade of life. The mean age was 39 years. A total of 93% of women were from the urban areas while 7% belonged to the rural areas. The majority of the women (78.5%) were multiparous and around 43% were second para. Pap smear reports were satisfactory in 93.5% of women in CPS, while 99% of reports were satisfactory in LBC. The difference between CPS and LBC in terms of the prevalence of satisfactory/unsatisfactory smear was statistically significant with a P = 0.0064. Dense inflammation reported by all LBC smears was reported as the same in CPS. The strength of agreement between CPS and LBC was not strong in terms of different grades of inflammation with a kappa value of 0.24. There was no difference in the reporting of cellular atypia between both methods.

Conclusions:

CPS and LBC are equal in terms of detection of inflammation and epithelial cell abnormality. Infections were also detected by both the screening methods CPS and LBC. The only thing which makes LBC better is the rate of satisfactory smears and the benefit of adding human papillomavirus DNA testing possible only in LBC.
Nocturnal wearing of complete dentures and obstructive sleep apnea: A meta-analysis
Authors: Jurel Sunit Kumar , Bakrolwala Husbana Altaf , Chand Pooran , Singh Raghuwar Dayal , Bhujbal Rushikesh Bhau , Singh Balendra Pratap
Published: October 2024

Statement of Problem:

Improvement in outcomes of obstructive sleep apnea (OSA) could answer the question of whether nocturnal wearing of removable complete dentures is beneficial.

Purpose:

To evaluate the available literature that compares nocturnal wearing of removable complete dentures or overdentures in patients diagnosed with OSA on the Apnea–Hypopnea Index (AHI), Epworth Sleepiness Scale (ESS), quality of sleep (Pittsburgh Sleep Quality Index [PSQI]) and other outcomes.

Methods:

Registration of the proposed protocol was done in an open-source registry. Databases (Medline, Embase, and Cochrane Central Register of Controlled Trials) were searched until August 2024. All the reports were screened by reading the abstracts and full texts by two independent reviewers and conflicts were resolved by the third reviewer in Covidence. Data extraction and risk of bias assessment as per the Risk of Bias 1.0 tool (RoB 1.0) were done in Covidence. Mean difference and risk ratios were used as effect measures for continuous and dichotomous outcomes. Statistical analysis was performed using a fixed effect model. The certainty of evidence was judged by the GRADE approach.

Results:

Out of 2428 available reports, three randomized controlled trials were included for statistical analyses involving a total of 123 participants. The pooled estimate for AHI showed no evidence of any difference with and without nocturnal wear of removable complete dentures (MD: 2.88; 95% confidence interval [CI]: 0.94 to 6.70; 246 participants). No evidence of any difference was found for PSQI (MD: 0.20; 95% CI: -0.97 to 1.37; 138 participants) and for ESS (MD: 0.20; 95% CI: -1.60 to 1.20; 138 participants).

Conclusion:

The review found insufficient evidence to judge that nocturnal wearing of removable complete dentures was effective in patients with OSA measured by Apnea Hypopnea Index, PSQI, and Epworth sleepiness scale.
Short implant versus conventional implant in the posterior atrophic maxilla: A systematic review and meta-analysis
Authors: Pradhan Yogamaya , Srivastava Gunjan , Choudhury Gopal Krishna , Sahoo Pradyumna Kumar , Padhiary Subrat Kumar
Published: October 2024

Objective:

A comparative study undertaken to measure the the marginal bone loss (MBL), implant survival rate, and prosthetic and biological complications among short implants (8 mm or shorter) and conventional implants (longer than 8 mm) in the posterior atrophic maxilla.

Materials and Methods:

A search in three databases PubMed (Medline), Scopus, and Cochrane was conducted. The present systematic review was registered with identification number CRD42020212805 at the International Prospective Register of Systematic Reviews. Data extraction included the publication year, patients’ number and number of implants, implant length and width, MBL, implant survival rate, and biological and mechanical complications. The Cochrane Risk of Bias 1.0 tool was used to assess the risk of bias. A meta-analysis was performed to evaluate the outcome variables. Comparisons for dichotomous variables, such as prosthetic and biological complications and implant survival rate, were done by applying the Mantel–Haenszel method. In contrast, a comparison was made by applying the inverse variance method for continuous variables like MBL.

Results:

Initially, 618 reports were recognized from electronic database searches. Five randomized controlled trials (RCTs) were included in the meta-analyses regarding the MBL, implant survival rate, and prosthetic complications, while three were included for biological complications. In 5 years of follow-up, no evidence of difference could be found between conventional and short implants for survival rate (risk ratio [RR]: 3.54; 95% confidence interval [CI]: 0.99–12.67; P = 0.05; I
2 = 0%). We do not find any evidence of difference for MBL between short implants and conventional implants (mean difference: −0.29; 95% CI: −0.49 to −0.08; P = 0.02; I
2 = 65%). Furthermore, no evidence of a difference exists between short and conventional implants for prosthetic complications (RR: 1.56; 95% CI: 0.68–3.55; P = 0.29; I
2 = 0%). The biological complications were seen less with short implants (RR: 0.47; 95% CI: 0.24–0.93; P = 0.03; I
2 = 0%).

Conclusion:

The results suggest no significant difference among conventional and short implants regarding survival rate in the posterior atrophic maxilla. The results of this systematic review and meta-analysis suggest that, for a 5-year period of follow-up, short implants are related to rarer biological complications and comparable MBL compared to conventional implants. Despite these promising findings, long-term studies with consistent study designs and clinical protocols are required to appraise the performance and durability of short implants.