bluuebunny/crossref_metadata_2025 huggingface dataset:
Improvement of Inspection and Repair Procedures for GE T700-701D Power Turbine Drive Shaft Assembly Pinning Hardware
Authors:   US Army AMRDEC - AEM, Ramos Victoria
Published: August 2024

Torque indicating issues continue to plague Power Turbine Modules (PTMs) as a top reason for return. These issues can be linked to failed torque and overspeed sensors and PTM torque reference shaft issues including; sticking shafts due to torque stiction and sheared pins connecting PTM drive shafts to torque reference shafts. At the end of the PTM shaft is the pinning hardware for the torque reference shaft. In shipping and during handling of the PTM damage can occur causing the pin to shear and fail. They can fail due to inadvertent contact with the PTM or torque shaft, during shipping and handling, or after prolonged usage. Defining a reliable inspection procedure to make the determination that the PTM shaft is faulty prior to ‘on wing’ installation can save time and money for the operator. In addition, the repair procedure for sheared pin is to replace pinning hardware at Corpus Christi Army Depot (CCAD) machine shop. During the repining of the hardware the holes must be located a minimum distance from each other to preserve the integrity of PT shaft and aft insert parent metal according to the Depot Maintenance Work Requirement manual. In the presence of machine shop error, failing to maintain the minimum distance between pin holes prevents viable PT shafts from use in production. Identifying a process improvement for repair procedures of pin hardware at the machine shop can save time and money invested in overhauled PT shafts for the depot.
Results of NASA Technical Challenge to Demonstrate Two-Speed Drive for Vertical Lift Vehicle
Authors:   NASA Glenn Research Center, Krantz Timothy , Handschuh Robert , Roberts Gary
Published: August 2024

Currently, manned vertical lift vehicles are flown in a manner such that the rotors operate over a narrow range of rotating speed regardless if the vehicle's flight condition is one of vertical takeoff and landing, hover, or forward cruise. The propulsion systems are optimized for operation at the same, corresponding narrow range of rotor speed. However, certain missions and markets benefit greatly if the rotor speed can be adjusted over a wide range of speed to match demands of different missions and flight regimes. A vehicle that can operate with a wide range of rotor speeds would address key barriers to enable new markets and missions for vertical lift vehicles. Key barriers addressed by the wide-range of rotor speed include noise reduced via lower rpm rotor, increase of maximum forward flight speed, increased payload and range, reduced fuel burn, and lower operating costs. A new paradigm for the propulsion system is needed to enable these key benefits. One viable approach is to make use of a two-speed ratio drive system such that the engine can continue to operate over a narrow speed range, whereby engine performance is optimal, while adjusting the rotor speed as needed using the two-speed drive system. Motivated by such needs and by results of several system studies, a NASA Revolutionary Vertical Lift Technology Challenge was established to develop and demonstrate required technologies and designs for achieving a 50 percent reduction in rotor rpm via a two-speed drive system that incurs less than 2 percent power loss and maintains current power-to-weight ratios. The technical challenge work was completed and the technical objectives were achieved. This report describes the motivations, the research approach and the significant outcomes.
Dynamic Analysis of Rotorcraft Planetary Gears Using a Finite Element/Contact Mechanics Model
Authors:   Southern Illinois University, Cooley Christopher ,   U.S. Army Research Laboratory, Hood Adrian
Published: August 2024

This study investigates the vibration of the OH-58A and OH-58C planetary gear stages at operating conditions using a finite element/contact mechanics model. These two planetary gears have identical sun, planet, and ring gears. They differ in the number of planets, the planet spacing, and the mesh phasing, which results in substantial differences in their vibration characteristics. The elastic vibrations at fixed points on the ring outer diameter of both planetary gears have spectra with frequency content in clusters near each harmonic of mesh frequency. The OH-58A planetary gear, which has equally-spaced planets and in-phase meshes, has the same frequency components near each harmonic of mesh frequency. They include response at mesh frequency harmonics and upper and lower sidebands at multiples of the planet pass frequency. The OH-58C planetary gear has different frequency content than the OH-58A because it has diametrically-opposed planet spacing and gear meshes that are out-of-phase. The frequency content near odd harmonics of mesh frequency differs from that near even harmonics. There is no response at odd harmonics of mesh frequency, and upper and lower sideband frequencies are prominent. Response occurs at even harmonics of mesh frequency. Upper and lower sideband frequencies occur at multiples of twice the carrier frequency. The amplitudes of the sideband frequencies are sensitive to the system's input torque.
Composites for Advanced Drive Systems, a Systems Analysis ­ Revolutionary Vertical Lift Technology (RVLT)
Authors:   The Boeing Company, Darmstadt Patrick , Robuck Mark
Published: August 2024

Rotorcraft propulsion systems are continually looking to improve power density; that is reducing weight and increasing power capacity and efficiency. In order to advance rotorcraft propulsion system technology, NASA Glenn Research Center (NGRC) contracted Boeing Vertical Lift to perform system level benefit assessments of designing composite materials into rotorcraft transmission gear and shaft systems. In general, the environment inside a typical rotorcraft transmission creates issues for typical composite materials. In flight critical gears and shafts, design challenges and safety risks associated with introducing composite materials must be understood and accounted for in the design. Boeing was able to develop a technical approach for the system study that covered a relatively large population of rotorcraft main transmissions. This technical approach evaluated rotorcraft from various size classes and configurations and applied parametric estimating methods to assess the performance impact of composite hybrid technologies inside transmissions, in the rotating frame. Parametric weight estimating showed that composite hybrid technologies account for an average 9% weight savings over the baseline transmissions. More weight savings may be observed when various other aircraft systems are considered. Tandem and Tilt-rotor aircraft use similar transmissions at the forward/aft rotor head and left/right side of the aircraft, respectively, doubling estimated weight savings of a single transmission. Other aircraft systems, such as airframe, landing gear, and fuel systems benefit from reduced propulsion system weight, and, therefore, lighter weight aircraft are possible when propulsion system weight is reduced.
In this paper, a systems level technical approach is summarized which was used to assess the performance impacts of introducing composite materials inside helicopter transmissions, in the rotating frame. Existing composite technologies, technical challenges, and general material selection guidance were used to develop the technical approach. Transmissions from a multitude of rotorcraft configurations and power classes were studied to build a database of expected performance gains. Component designs were developed using composite materials to varying levels of fidelity in order to develop data used for parametric weight estimating. The component designs are compiled and averaged with similar, existing designs in order to build a robust dataset for weight estimating purposes. Using information developed during the component design phase, technical challenges were defined.
Advantages of Early System Safety Influence
Authors:   Sikorsky Aircraft, Hewitt John , Foito Daniel
Published: August 2024

System safety is the application of engineering and management principles, criteria, and techniques to achieve acceptable mishap risks. As modern rotorcraft designs become ever more complex, system safety becomes ever more essential. System safety typically reduces mishap risks through analyses that identify and address potential system failure modes. Documents such as MIL-STD-882, SAE ARP4754, SAE ARP4761, and the Federal Aviation Administration (FAA) System Safety Handbook guide the various analyses that are performed in the system safety process. The use of these analyses to reduce mishap risks is not new, but case studies indicate that if the system safety process is applied to influence rotorcraft designs earlier in the product life cycle, schedule slippage and cost escalation resulting from design changes can be substantially reduced. In addition, earlier completion of system safety analyses permits corrective actions to be implemented at a higher level in the system safety order of design precedence, which increases the effectiveness of the corrective actions and reduces residual risk. This paper provides examples that will encourage earlier completion of system safety analyses by demonstrating the cost and schedule advantages, as well as the expected safety risk reduction.
History of System Safety
Authors:   Sikorsky Aircraft, Braman Gary
Published: August 2024

The concept of system safety was first introduced in the 1940s. However, prior to that, safety was generally achieved by attempting to eliminate hazards in the initial design and then correcting other problems as they appeared after a product was in use or at least in a testing phase. In other words, a trial and error methodology was utilized. In aviation, this became known as the "fly-fix-fly" approach. An aircraft would be designed using the best knowledge available, flown until it crashed, then fixed and flown again. These approaches were not adequate for systems that had to be first-time safe. Thus began the concept of system safety and its evolution. The engineering and safety communities developed the concept in order to design and build safer equipment by applying lessons learned from accident investigations. In response to the dissatisfaction with the "fly-fix-fly" approach, the following decades saw many new developments in the system safety concept.
Development of Powered-Lift Airworthiness Standards as Applied to the AW609 Tiltrotor Certification Basis
Authors:   AgustaWestland Philadelphia Corp., Fraser William , King David , Schaeffer Joseph , Wells Dan
Published: August 2024

The primary purpose of the paper is to describe the safety considerations used to define the airworthiness requirements incorporated into the AW609 certification basis and how this forms the basis for airworthiness standards for a new powered-lift category of aircraft. The paper will provide a general history of and the process used to determine the certification basis, and provide specific examples of how the regulations reflect safety requirements. Examples of how the AW609 plans to meet the requirements are described. Specific examples given in this paper include, but are not limited to, definition and compliance to specific safety requirements (TR.1309), considerations for the unique flight control system including a nacelle conversion control device, pilot training requirements, ditching, fuel reserves, Transport Category Performance (ability to safely take off and land after an engine failure), All-Engines-Inoperative (AEI) operations, including autorotation. Each of these items will be expanded and described.
Structural Multifunctionality for Weight Reduction
Authors:   US Army - Aviation Development Directorate, Robeson Mark
Published: August 2024

The US Army's Aviation Development Directorate (ADD) has successfully collaborated with its industry partners to reduce system parasitic weight for aviation platforms through multifunctional structures technology development. In short, this can be generalized as achieving weight savings by replacing the combination of aircraft structure and an independent, add-on mission enabler with a singular system that performs the functions of both structure and mission enabler. This extensive multifunctional technology development for aviation structural applications has yielded significant weight savings over parasitic designs. Technologies demonstrating this structural multifunctionality for weight reduction include integrally armored helicopter floor, lightweight integrally armored helicopter floor, lightning-protected structure, structural antenna aperture, helicopter empennage antenna structure, combat tempered aft fuselage, blast attenuating aircraft structure, and highly durable floor armor for rotorcraft. The significance of weight savings that can be enabled via multifunctional structures technology development is clear. One case study exercise indicates a platform-level mission enabler weight savings of 17.8%. This significance of weight savings is analogous to other studies showing synergistic benefits from technology integration at the technology and system (platform) level.
Product Line Engineering (PLe) within in a Product Line Enterprise (PLE) leveraging Model-Based System Engineering (MBSE) to Achieve Technologically Enabled Architecture Centric Virtual Integration Process (ACVIP)
Authors:   Dassault Systèmes, Thurston Garrett , Guzinsky David , Pond Kendall , Adami-Sampson Mike , Carter Matthew
Published: August 2024

This paper seeks to position Product Line Engineering (PLe) in the context of an enterprise which endeavors to achieve improved business execution outcomes resulting from the implementation of a Product Line Enterprise (PLE) and Model Based Systems Engineering (MBSE). This topic is relevant to the vertical lift community in that it is one of the major enabling approaches to improved acquisition execution of the Future Vertical Lift program (FVL). It is crucial that the foundational tenets of the PLe are extended to the product line management at the enterprise level to fully realize the business promise. Failing to connecting elements of the critical chain may result in diminished business benefits.
Wind Tunnel Test Results for an Overlapped Quadrotor Configured UAS
Authors:   US Army CCDC AvMC, Chen Geoffrey ,   Engility Corporation, Russell Carl , Nunez Gerardo , Avera Michael , Ames NASA
Published: August 2024

The Aviation Development Directorate of the U.S. Army Aviation and Missile Research, Development and Engineering Center (AMRDEC), in cooperation with the U.S. Army Research Laboratory and the NASA Ames Research Center Aeromechanics Office, conducted wind tunnel tests of an Overlapped Quadrotor (OQ) configured UAS in the U.S. Army 7- by 10-foot Wind Tunnel at the NASA Ames Research Center, Moffett Field, CA. The OQ was one of multiple quadrotor aircraft that were tested in the 7- by 10-foot Wind Tunnel in January 2017. The OQ is a prototype overlapping, shrouded rotor, quadcopter aircraft that was developed by Malloy Aeronautics and modified by the Army Research Laboratory (ARL). A novel design characteristic of the OQ revolves around the arrangement of its rotors – pairs of diametrically opposed overlapping shrouded rotors are oriented in opposite directions and opposing geometric planes, while the overall thrust direction is uniform, achieved via pairs of counter-rotating rotors. The purpose of the test was to evaluate the aircraft performance over a variety of projected flight conditions, while also quantifying the aerodynamic interaction effects of an overlapping shrouded rotor design. The test is described here in detail, and a selection of the key results from the test is presented.
Collaborative Uncertainty-aware Navigation for Vision based Multirotor Swarms
Authors:   Texas A&M University, Vemprala Sai , Saripalli Srikanth
Published: August 2024

In this paper, we present a framework for collaborative uncertainty-aware navigation for swarms of vision based multirotor micro aerial vehicles (MAV). We assume that each MAV in a swarm is equipped with a forward-facing monocular camera, and that the vehicles are capable of using feature data to map the environment and perform vision based localization. Additionally, the vehicles are also capable of computing relative poses between each other in order to improve accuracy of pose estimation. For this scenario, we develop a navigation framework which seeks to improve the reconstructed maps and plan trajectories such that localization uncertainty is minimized. Within this framework, we first utilize an evolutionary algorithm that generates better viewpoints for the MAVs from which the map of the environment can be improved. This generated map is subsequently used as a source of information to perform path planning for each vehicle using a rapidly exploring random belief tree. This algorithm, while connecting start and goal poses with collision-free trajectories, ensures that the vehicles prioritize observing feature-rich areas and never lose sight of features, thus improving localization accuracy. Additionally, the algorithm is also capable of estimating when corrections would be required through relative poses and where these observations should be obtained, such that one vehicle can improve the accuracy of its neighbors. Through these approaches, we generate smooth, uncertainty-aware paths that are suitable for MAV navigation.
Post-Rotor-Failure Performance of a Feedback Controller for a Hexacopter
Authors:   Rensselaer Polytechnic Institute, McKay Michael , Niemiec Robert , Gandhi Farhan
Published: August 2024

A feedback controller is designed and implemented for a regular hexacopter based on the AeroQuad Cyclone ARF kit. This controller is designed with an inner loop control law as a set of parallel PID controllers for aircraft altitude, pitch, roll, and yaw attitudes, as well as an outer loop for control over aircraft body velocities. Rotor failure is modeled in the dynamic simulation by setting the rotor force and moment output to be zero regardless of the commanded control input to that rotor, the feedback controller utilizes no knowledge of this fault during simulation. Various trajectories are commanded to examine the performance of the baseline feedback controller in the event of forward rotor failure, including hover, forward flight, and more complex maneuvers. The controller is demonstrated to recover the aircraft states after the transient effects of the rotor failure, as well as complete the defined state trajectory, demonstrating tolerance to single rotor failure.
Physical fitness profile of primary school learners in the Eastern Cape province of South Africa
Authors: Gomwe Howard , Phiri Lesego , Marange Chioneso S.
Published: August 2024

Background: Low levels of physical activity in high- to low-income countries, including South Africa, pose a great risk of cardiovascular-related diseases.Aim: This study aimed to assess and compare the physical fitness profile among children.Setting: The study setting comprised rural and urban primary school learners in the Eastern Cape province, South Africa.Methods: A cross-sectional study was adopted utilising a randomly selected sample of boys and girls aged 9–14 years. Physical fitness measures were assessed using the Euro-fit test battery. Some parametric tests were used for mean comparisons of the various anthropometric measurements and physical fitness characteristics across demographics.Results: The sample consisted of 870 primary school learners. The average weight and height of the sample were 39.29 ± 10.34 kg and 144.06 ± 10.81 cm, respectively, with a mean body mass index (BMI) of 18.80 ± 4.11 kg/m2. The results showed that boys reported significantly high levels of physical fitness. Sit-ups (p ≤ 0.001) and VO2 max (p ≤ 0.001) significantly increase with age, while all the physical fitness measures were significantly higher among rural-based learners.Conclusion: Rural-based learners and boys generally had better physical fitness performance than their peers. The effect of gender and place of residence should be considered when designing physical fitness interventions.Contribution: This study adds to the existing body of knowledge about the effect of demographic factors on the physical fitness profile of children, where boys and rural-based learners are reported to be more physically fit than their counterparts.
Comparative analysis of PDL1 and cluster of differentiation 68 marker expression in oral squamous cell carcinoma patients: Correlation with depth of invasion and immunofluorescence through immunohistochemistry
Authors: Shahabinejad Mehdi , Bagheri Shirvan Siavash , Fatemi Golnaz , Mohajer Tehran Farnaz
Published: August 2024

Background:

Over the past 5 years, the use of immune checkpoint inhibitors in the treatment of head-and-neck squamous cell carcinoma (HNSCC) has increased. Both programmed death-ligand 1 (PD-L1) and cluster of differentiation 68 (CD68) are overexpressed in various carcinomas. Consequently, evaluating the expression of CD68 and PD-L1 in HNSCC lesions may lead to detecting a possible marker for HNSCC. This study aimed to evaluate the expression of PDL1 and CD68 markers in a patient with oral squamous cell carcinoma (OSCC) and examine its relationship with depth of invasion (DOI) and immunofluorescence (IF) through immunohistochemistry.

Materials and Methods:

This cross-sectional study was conducted in the School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran, Department of Oral and Maxillofacial Pathology. Thirty-four paraffin blocks and demographic information of 15 female and 19 male OSCC patients were collected. Following sample preparations, immunohistochemical staining was performed. Subsequently, each tissue section was analyzed for tumor-infiltrating lymphocytes by CD68 marker and PD-L1 expression. Data analysis was conducted using SPSS software (version 25). Chi-square, Shapiro–Wilk, and independent t-analytical tests were employed for statistical assessments. P < 0.05 was remarked as statistically significant.

Results:

CD68 and PDL1 expression in the squamous cell carcinoma (SCC) group was higher than the control group (P < 0.001). There was an increasing expression of PDL1 and CD68 as the grade of the disease progressed (P < 0.001 for each), as well as an increasing expression of IF and DOI.

Conclusion:

The expression levels of CD68 and PDL1 were elevated in SCC tissues in comparison to the unaffected, healthy parts of the tissue section.
Influence of temperament on children’s cooperation during dental treatment
Authors: Mehrabkhani Maryam , Khanmohammdi Razie , Nematollahi Hosein , Rajabi Nikoo , Gheidari Ali
Published: August 2024

Background:

The etiologies of childhood dental fear/dental behavior management problems have been extensively studied, especially the role of children’s temperaments. This study aimed to evaluate the effect of temperament and its associated variables on the anxiety and cooperation level of preschool children in a dental clinic.

Materials and Methods:

This cross-sectional study involved 103, 4–6-year-old patients (39 boys and 64 girls). The children’s parents or guardians completed the Child Fear Survey Schedule (CFSS) Dental Subscale and the Malhotra temperament questionnaire before the treatment. Patients’ anxiety and cooperation levels were then assessed through three distinct treatment stages of fluoride therapy, injection of local anesthesia, and drilling, by applying the Venham anxiety and clinical cooperation scales. The data were analyzed using analysis of variance, Mann–Whitney, Kruskal–Wallis, and Chi-square tests. The significance level of 0.05 was deemed relevant in the analysis.

Results:

A significant correlation was established between the mean of CFSS and the variety of temperament (P = 0.001). Anxiety and uncooperative behavior during injection and drilling were strongly related to lower sociability scores. Furthermore, higher anxiety during the drilling stage was related to higher impulsivity scores.

Conclusion:

The evaluation of children’s anxiety and cooperation in dental clinics heavily relies on temperament and certain related factors, such as sociability. These variables serve as crucial benchmarks in understanding and assessing the psychological state of children during dental procedures.
A Case Report on Wolff–Parkinson–White syndrome in Pregnancy
Authors: Ashwini K. N.
Published: August 2024

Wolff–Parkinson–White syndrome (WPWS) is a rare congenital pre-excitation syndrome characterised by the presence of an accessory pathway that predisposes to tachyarrhythmia and sudden death. A 26-year-old G4P1L1A2 woman was admitted at 11 weeks of gestation with complaints of headache, vomiting, chest pain and palpitation. ECG elicited supraventricular tachycardia, short PR interval and wide QRS complex. With a reactive non-stress test, the patient was continuously monitored and treated with beta-blockers. Both pregnancy and the WPWS aggravate each other’s tendency to produce arrhythmias. Adequate preparation with fluid preloading and positioning, securing appropriate drugs and emergency equipment, avoidance of tachyarrhythmia and prompt treatment on occurrence is required for the safety of both the mother and the foetus. Prompt diagnosis and rigorous and collaborative team management are very essential to save the patient’s life.
Investigation of Wastewater Treatment Plant Behavior for Residential Community within 1 Year
Authors: Mareai Basim M. , Marshdi Qosai Sahib Radi , Hussein Hadeel M. , Al-Khafaji Zainab S. , Al-Husseinawi Fatimah , Abdulrahim Firas R. , Janabi Amjed S. Kamil
Published: August 2024

Aim:

The effluent generated from wastewater treatment plant (WWTP) is a mixture of several chemicals, including, salts, chemical solvents, strong acidic, and alkaline so the study aimed to investigate the performance and characterization of the WWTP in a residential community to evaluate within the limits of the design of the plant.

Methods:

For the studying performance of (WWTP), the samples were collected before interred the treatment unit (influent) and after exiting from the treatment unit (effluent) in 24 plastic bottles for each time during 1 year, and used for analysis as chemical oxygen demand (COD), biochemical oxygen demand (BOD), total suspended solid (TSS), PO4, nitrate, chlorine, hydrogen sulfide, and oil, and grease (O and G) parameters and investigated the efficiency of remove to BOD, COD, TSS, and O and G.

Results:

Results showed the removal efficiency of BOD, COD, TSS, O and G and PO4 in the WWTP as 91%, 82.8%, 83.5%, 67.4%, and 64.7%, respectively, from June 7, 2018, to December 16, 2018. The experimental results indicated that the period from January to March demonstrates the best removal efficiency of COD. Furthermroe, it indicated that suddenly changing amounts in influent had an adverse decrease in the efficiency of biological systems.

Conclusions:

The performance of SBR was good which was reflected in the final effluent. The finding may back to cumulating high parameter amounts that inhibit microorganism activities when all nutrients were low in the wastewater that wanted to microorganism’s growth. The results proved the solubility of effluent to be discharged on the sewer system and used for irrigation purposes (based on its characteristics).
Proportion of Emergency Cesarean Section in Maternity Hospitals in Kirkuk Governorate, in 2022–2023
Authors: Khalaf Enas Ibrahim , Al-Kaseer Eman Adnan
Published: August 2024

Background:

Emergency cesarean sections are undertaken before or during labor when there is an immediate concern for the mother or the fetus. Inadequate maternal management and unreliable referral systems are responsible for the massive incidence of emergency cesarean section.

Objectives:

This study aims to identify the rate of emergency cesarean section in Kirkuk governorate.

Subjects and Methods:

A cross-sectional study was conducted at the postoperative Obstetrical and Gynecological wards in Azadi Teaching Hospital and Kirkuk General Hospital, Kirkuk, Iraq, from December 1st, 2022, to February 28th, 2023. Four hundred women, who have had cesarean sections, were directly interviewed using a structured questionnaire. Official approval was obtained. Categorical data were analyzed using the Chi-square or Fisher’s exact tests P < 0.05 was considered statistically significant.

Results:

One hundred and ninety-nine (49.8%) mothers were within 26–35 years of age. One hundred and forty-three (35.8%) had an emergency cesarean section, whereas 257 (64.3%) had an elective cesarean section. Emergency indications included failure to progress 45 (31.5%), cephalopelvic disproportion (CPD) 36 (25.2%), fetal distress 32 (22.4%), and severe preeclampsia 22 (15.4%). Poor pregnancy outcomes included bad obstetrical history 49 (12.3%), macrosomia 7 (1.8%), premature rupture of membrane 4 (1.0%), and postterm 21 (5.3%). Elective cesarean sections were significantly higher in husbands >35 years, with husbands’ education (primary school), parity of 2–4, and with no pregnancy-induced hypertension (P = 0.035, P = 0.034, P < 0.001, and P < 0.001), respectively. Emergency cesarean sections (CSs) were significantly higher among diabetic mothers; P = 0.022.

Conclusions:

One-third of all CSs in Kirkuk were done as emergency operations with failure to progress, CPD, and fetal distress as the main indications.
Low Attendance of Lectures among Medical Students
Authors: Hanoon Yossra Khalaf , Hadi Zeena Mohammed Fahmi , Al-Ani Waleed Arif
Published: August 2024

Background:

Absenteeism is defined as the frequent nonattendance from classes with no reasonable cause. Nonattendance affects the teaching–learning practice and affects the well-being of the class. Causes given by students for absenteeism were lack of time, illness boring, or unexciting lecture topics.

Aim of the Study:

The aim of this study was to determine the absenteeism behavior among students of the medical college of Al-Mustansiriyah University, Iraq, to find out the causes behind lectures’ nonattendance, and to demonstrate the rate of the most common causes.

Materials and Methods:

A cross-sectional study, descriptive study, was conducted at Al-Mustansiriyah University, College of Medicine, with a convenient sample from the third, fourth, and fifth classes, in March 2019 for 3 weeks, using a special questionnaire was made especially for the purpose of the study, and data analysis was performed using Excel trial version software and the use of descriptive statistical techniques.

Results:

About two-thirds of the students missed approximately 0–5 lectures per week. The qualities of lecturers, their training, and the relationship they have with the students appear to play a role in attending lectures. The results show that about one-third of students consider the difficult subject and their desire to benefit from the lecture influenced their decision to attend. The most common cause chosen for nonattendance was having an examination on the next day, about 66%, and lecturer expression was 63%. The most common cause for missing morning lectures was traffic problems, 53%.

Conclusion:

The lecture attendance rate was low, and the main reasons for absenteeism from lectures were the presence of the examination, poor lecturer teaching style, and boring lecture topics.
Knowledge, Practices, and Barriers of Communication Skills among a Group of Primary Health-care Physicians in Baghdad 2023
Authors: Mohammed Zahra’a Ahmed , Mohammed Ghaith Sabri
Published: August 2024

Background:

Communication skills are essential for health professionals to achieve a positive relationship with patients, improving their health and quality of life. Communication is the foundation for obtaining medical history and conveying a diagnosis and treatment plan.

Objectives:

To assess the knowledge, practice of communication skills among primary care physicians, to find out any barriers related to the communication skills, and the association between the studied variables with knowledge and practice of communication skills.

Methodology:

A cross-sectional study with analytic component conducted in 40 Primary Health Care Centers in Baghdad, with data collection during a period of 4 months from March 1, 2023 to June 30, 2023. Data had been collected in a questionnaire by direct interview with the participants done by the researcher and including three parts: (participants’ sociodemographic characteristics, knowledge, practice toward communication skills, and the barriers to successful communication).

Results:

The total number of the participants was 126. The level of knowledge of the participants about physician-patient communication skills was fair in 74 (58.7%) of them, poor in 35 (27.8%). The highest prevalence of poor level of knowledge was seen in participants with specialties other than family medicine and in those with more than 20 years of experience. Level of practice of the participants toward physician-patient communication skills was good in 63 (50%) of them and 63 (50%) had moderate level of practice. The highest prevalence of moderate level of practice was seen in elderly age participants. The most common barrier as mentioned by the participants was time limitation.

Conclusion:

The majority of primary health-care physicians in this study have fair levels of knowledge, with moderate to good level of practice about communication skills. Family physicians and those who had experience between 10 and 19 years had better knowledge about communication skills. Time limitations are perceived as the biggest hindrance to communication followed by the presentation with multiple complains.
Unmet Needs and Barriers to Assistive Technology in the Coastal Districts of Karnataka, India
Authors: Kamath Ramachandra , Fernandes Edmond , Dsouza Neevan , Ghai Glory , Kamath Surekha R.
Published: August 2024

Background:

Assistive Technologies (AT), such as hearing aids, walking aids, prostheses, spectacles, can improve the quality of life and enable many to lead dignified lives. The rapid Assistive Technology Assessment (rATA) tool developed by World Health Organization (WHO) can measure the needs of AT and the barriers to accessing them.

Objective:

This study aimed to measure the unmet needs and the usage of AT via the rATA tool in the coastal state of Karnataka in India.

Methodology:

A population-based survey was conducted among a total of 500 households - 250 from Mangalore and 250 from Udupi of Coastal Karnataka. The need for AT was assessed under six domains of activities, including mobility, seeing, hearing, communication, remembering, and self-care.

Result:

The mean age of study participants was 34.3 years with standard deviation of 21.2 years. 30.6% of the study participants reported the use of assistive products out of which 27.3% used one product and 2% used two products. 89.5% of assistive products were procured from private sector and only 4.1% was obtained from public sector. The level of difficulty in doing any activity increased with age. 301 participants reported out of pocket expenditure for assistive products with mean expenditure of Rs 2226.05 (S. D. 2204) per year. Spectacles, orthoses (spinal) and therapeutic footwear were most common assistive products with unmet need.

Conclusion:

Our findings highlight the urgent need to mainstream geriatric care policies which address functional difficulties among older people, resolve out-of-pocket spending through public private partnership for assistive technologies.
Enhancing User Query Comprehension and Contextual Relevance with a Semantic Search Engine using BERT and ElasticSearch
Authors: Ladanavar Saniya M , Kamble Ritu , Goudar R.H , Kaliwal Rohit. B. , Rathod Vijayalaxmi , Deshpande Santhosh L , G M Dhananjaya , Kulkarni Anjanabhargavi
Published: August 2024

This research paper explores the development of a semantic search engine designed to enhance user query comprehension and deliver contextually applicable research results. Classic search engines basically struggle to catch the nuanced meaning of user queries, giving to suboptimal results. To address this challenge, we give the merge of advanced natural language processing (NLP) techniques with Elasticsearch, and with a specific focus on Bidirectional Encoder Representations from Transformers (BERT), a state-of-the-art pre-trained language model. Our approach involves leveraging BERT's ability to analyze the contextual meaning of words within documents by sentence transformers as (SBERT) , enabling the search engine to grab the user queries and better under- stand semantics of the content as it is converted into vector embeddings making it understandable in the Elasticsearch server. By utilizing BERT's bidirectional attention mechanism, the search engine can discern the relationships between words, thereby capturing the contextual nuances that are crucial for accurate query interpretation. Through experimental validation and performance assessments, we demonstrate the efficacy of our semantic search engine in providing contextually relevant search results. This research contributes to the advancement of search technology by enhancing the intelligence of search engines, ultimately improving the user experience by giving context based research.
Tuberculosis detection bars on VGG19 transfer learning and Zebra Optimization Algorithm
Authors: Le Tianzhi , Shi Fanfeng , Ge Meng , Dong Ran , Shan Dan
Published: August 2024

Tuberculosis (TB) remains a significant global health challenge, necessitating accurate and efficient diagnostic tools. This study introduces a novel approach combining VGG19, a deep convolutional neural network model, with a newly developed Zebra Optimization Algorithm (ZOA) to enhance the accuracy of TB detection from chest X-ray images. The Zebra Optimization Algorithm, inspired by the social behavior of zebras, was applied to optimize the hyperparameters of the VGG19 model, aiming to improve the model's generalizability and detection performance. Our method was evaluated using a well-defined metric system that included accuracy, sensitivity, and specificity. Results indicate that the combination of VGG19 and ZOA significantly outperforms traditional methods, achieving a high accuracy rate, which underscores the potential of hybrid approaches in TB image analysis.
Serological evidence of Coxiella burnetii in sheep herds from Lonquimay valley in the Chilean Andes
Authors: Alocilla-Velásquez Oscar , Navarrete Scarlet , Alfaro-Chat Carmina , Padilla Robert
Published: August 2024

Coxiella burnetii is the causative agent of Q Fever, a worldwide zoonotic disease that causes acute flu-like illness and chronic manifestations in humans in the form of endocarditis, hepatitis, and other symptoms. Domestic ruminants are the most important reservoirs of the bacteria, transmitting infections to humans during the calving/lambing season through direct contact with contaminated fetal tissues or inhalation of dust particles. The aim of this study was to provide serological evidence and estimate the individual true seroprevalence of C. burnetii exposure in sheep herds in Lonquimay, and to characterize farmers’ knowledge of coxiellosis. A disease freedom survey was conducted in 30 sheep herds selected from the Indigenous Territorial Development Program database (PDTI). A total of 260 blood samples were tested using ELISA for C. burnetii antibody detection. Disease freedom and true animal-level prevalence were estimated, and a questionnaire was administered during farm visits to characterize farmers’ zoonotic knowledge. A positive result was found in 3% (1) of the sampled herds, and the true animal prevalence (mTALP) was higher than previous unpublished estimations (mTALP 4.2%, 95% PPI 1.6%–9%). The estimated probability of the study sheep population not being free of C. burnetii was 34%. A lack of knowledge regarding C. burnetii or the consequences of Q Fever was detected, along with risky behaviors that could facilitate pathogen transmission. This study revealed evidence of exposure to C. burnetii, with low individual and herd-level prevalence. Initiatives to improve zoonotic knowledge among farmers need to be implemented in the short term.
Bridging the gap: Addressing disparities in hepatitis C screening, access to care, and treatment outcomes
Authors: Alenzi Maram , Almeqdadi Mohammad
Published: August 2024

Hepatitis C virus (HCV) is a significant public health challenge globally, with substantial morbidity and mortality due to chronic liver disease. Despite the availability of highly effective and well-tolerated direct-acting antiviral therapies, widespread disparities remain in hepatitis C screening, access to treatment, linkage to care, and therapeutic outcomes. This review article synthesizes evidence from various studies to highlight the multifactorial nature of these disparities, which affects ethnic minorities, people with lower socioeconomic status, individuals with substance use disorders, and those within correctional facilities. The review also discusses policy implications and targeted strategies needed to overcome barriers and ensure equitable care for all individuals with HCV. Recommendations for future research to address gaps in knowledge and evaluation of the effectiveness of interventions designed to reduce disparities are provided.
Tissue inhibitor of metalloproteinase-3 expression affects clinicopathological features and prognosis of aflatoxin B1-related hepatocellular carcinoma
Authors: Liang Qiu-Ju , Long Qin-Qin , Tian Feng-Qin , Su Qun-Ying , Zhu Xiao-Ying , Long Xi-Dai
Published: August 2024

BACKGROUND

The dysregulation of tissue inhibitor of metalloproteinase-3 (TIMP3) was positively correlated with the progression of hepatocellular carcinoma (HCC). However, it is not clear whether TIMP3 expression is associated with the clinicopathological features and prognosis of aflatoxin B1 (AFB1)-related HCC (AHCC).

AIM

To assess the effects of TIMP3 expression on the clinicopathological features and prognosis of AHCC.

METHODS

A retrospective study, including 182 patients with AHCC, was conducted to explore the link between TIMP3 expression in cancerous tissues and the clinicopathological characteristics and prognosis of AHCC. TIMP3 expression was detected by immunohistochemistry and its effects on the clinicopathological features and prognosis of AHCC were evaluated by Kaplan-Meier survival analysis and Cox regression survival analysis. Odds ratio, hazard ratio (HR), median overall survival time (MST), median tumor recurrence-free survival time (MRT), and corresponding 95% confidential interval (CI) was calculated to evaluate the potential of TIMP3 expression in predicting AHCC prognosis.

RESULTS

Kaplan-Meier survival analysis showed that compared with high TIMP3 expression, low TIMP3 expression in tumor tissues significantly decreased the MST (36.00 mo vs 18.00 mo) and MRT (32.00 mo vs 16 mo) of patients with AHCC. Multivariate Cox regression survival analysis further proved that decreased expression of TIMP3 increased the risk of death (HR = 2.85, 95%CI: 2.04-4.00) and tumor recurrence (HR = 2.26, 95%CI: 1.57-3.26). Furthermore, decreased expression of TIMP3 protein in tissues with AHCC was significantly correlated with tumor clinicopathological features, such as tumor size, tumor grade and stage, tumor microvessel density, and tumor blood invasion. Additionally, TIMP3 protein expression was also negatively associated with amount of AFB1-DNA adducts in tumor tissues.

CONCLUSION

These findings indicate that the dysregulation of TIMP3 expression is related to AHCC biological behaviors and affects tumor outcome, suggesting that TIMP3 may act as a prognostic biomarker for AHCC.
Intelligent Vehicle Path Tracking and Stability Cooperative Control
Strategy Based on Stable Domain
Authors: Jiang Shuhuai , Wu Guangqiang , Li Yihang , Mao Libo , Zhang Dong
Published: August 2024

Vehicle path tracking and stability management are critical technologies for
intelligent driving. However, their controls are mutually constrained. This
article proposes a cooperative control strategy for intelligent vehicle path
tracking and stability, based on the stable domain. First, using the vehicle’s
two-degrees-of-freedom (DOF) model and the Dugoff tire model, a phase plane
representation is constructed for the vehicle’s sideslip angle and sideslip
angular velocity. An enhanced method utilizing five eigenvalues is employed to
partition the vehicle stability domain. Second, by employing the divided vehicle
stable domain, the design of a fuzzy controller utilizes the Takagi–Sugeno (TS)
methodology to determine the weight matrix gain for path tracking and stability
control. Subsequently, a fuzzy model predictive control (TS-MPC) cooperative
control strategy is designed, which takes into account both the precision of
path tracking and the stability of the vehicle. Finally, a simulation test and
comparative analysis with a generic MPC controller were conducted. The findings
indicate that compared to the generic MPC cooperative controller, the control
strategy designed in this article markedly enhances the stability of the vehicle
and boosts the accuracy of path tracking.
Salud y Especialidades Médicas
Authors: ECUADOR FECIM
Published: August 2024

"Salud y Especialidades Médicas" es más que un libro; es un compendio de vivencias y experiencias que trazan el camino hacia la vocación médica y su consolidación en las distintas especialidades. En sus páginas, se recogen historias profundamente humanas, relatos que nos acercan al mundo interior de médicos, odontólogos, nutricionistas y enfermeros, desde sus primeros años de formación hasta la elección de la especialidad que marcará sus trayectorias profesionales.
Este ejemplar, nos invita a conocer de cerca el lado más humano de la medicina, aquel que no siempre se ve en las aulas ni en los consultorios, pero que es fundamental para entender la dedicación y el amor por una profesión que, en última instancia, tiene como objetivo aliviar el dolor, salvar vidas y mejorar la calidad de vida de las personas. Este libro inspira y ofrece una visión íntima de lo que significa ser un profesional de la salud en su máxima expresión.
Helping to Make the Complex Accessible: A Review of Larsen and Adu’s The Theoretical Framework in Phenomenological Research: Development and Application
Authors: Greenquist-Marlett Stephanie
Published: August 2024

Understanding the philosophical underpinnings behind phenomenological research is critical for pursuing a proper qualitative study on one’s lived experiences. Larsen and Adu’s The Theoretical Framework in Phenomenological Research: Development and Application succeeds in breaking down the theoretical viewpoints and methodology of phenomenology and delivering it in a manageable way for researchers and practitioners alike. While novices may find the complexity of the theoretical content comparing Edward Husserl’s transcendental approach and Heidegger’s hermeneutic Dasein framework to be daunting, the book does lend itself as an instructional tool that offers easy-to-follow guidelines for those at any experience level interested in pursuing a phenomenological research design.