bluuebunny/crossref_metadata_2025 huggingface dataset:
Definitive radiotherapy with nodal boost for radiologically positive nodes in carcinoma cervix – A retrospective cohort study
Authors: Alexander F Hadrian Noel , Udayashankara Avinash H. , Nirmala S , Sebastian M G John , Muzumder Sandeep , Raju Jayalekshmi , Tripathy Arkaja , Ghosh Santu
Published: December 2024

Background and Purpose:

Definitive radiotherapy (RT) with concurrent cisplatin-based chemotherapy (CT) is the standard of care for the treatment of locally advanced carcinoma uterine cervix. Lymph node (LN) metastasis is one of the major prognostic factors. We plan to analyze the node-positive carcinoma cervix (NPCC) patients treated at our institution.

Materials and Methods:

All NPCC treated with Definitive RT with or without concurrent CT from January 2013 to December 2021 were included in the analysis. Patients were treated to a dose of 4500 cGy, and the gross LNs were boosted to a dose of 6000 cGy in conventional fractionation (180-200 cGy) using three-dimensional conformal radiotherapy or intensity modulated-image guided radiotherapy (3DCRT/IM-IGRT) along with high dose rate (HDR) brachytherapy. We plan to analyze overall survival (OS), disease-free survival (DFS), toxicities, and various factors that might impact the outcome of treatment.

Results:

92 patients were eligible for analyses. With a median follow-up of 36 months, two patients lost to follow-up. The 3-year and 5-year OS was 86% and 77%, respectively. On log-rank analysis, the number of LNs boosted significantly impacted the OS but not with any other factors. The 3-year and 5-year DFS was 81% and 77%, respectively. There were 16 (17.2%) Grade 3 acute toxicities in 15 patients. The most common acute toxicity was gastrointestinal (6.45%). Four patients (4.3%) had developed Grade 3-4 late toxicity.

Conclusions:

Definitive radiotherapy with concurrent chemotherapy for NPCC with boost to the enlarged LNs results in good survival outcomes with acceptable toxicities.
Assessment of pulmonary function tests in carcinoma esophagus patients treated with three-dimensional conformal radiation therapy versus intensity-modulated radiation therapy
Authors: Goyal Navik , Garg Pardeep , Kaur Kiranjit , Kang Manraj , Grover Romi , Singh Simrandeep , Kaur Gurpreet , Gaur Garima
Published: December 2024

Background:

Three-dimensional conformal radiation therapy (3DCRT) provided enhancement in target delineation for the avoidance of normal structures, but considerable doses are still received by normal tissues. Intensity-modulated radiation therapy (IMRT) manipulates the photon beams of radiation to conform to the shape of a tumor and deliver precise radiation doses to the tumor, while sparing normal tissues. The distinct dosimetric advantages of IMRT have been proven by various studies.

Materials and Methods:

Forty histologically proven esophageal carcinoma patients were treated in ARM A (3DCRT) and ARM B (IMRT) and were evaluated for clinical lung toxicity in each arm. Pulmonary function tests and chest radiographs were done preradiotherapy, 6 weeks of radiotherapy, and 6 months of radiotherapy for evaluation and thereafter compared for lung toxicity between both arms. RTOG lung toxicity grading was used to assess clinical lung toxicity.

Results:

We observed in the present study that lung toxicity was seen in patients of esophageal cancer postradiotherapy in both modalities. It was less in IMRT than 3DCRT but not of significant difference. Various levels of restriction were seen in pulmonary function test or spirometry that is mild, moderate, or severe. At 6 weeks of radiotherapy, in ARM A, five patients (25%) and in ARM B, and four patients (20%) had moderate restriction (P value = 0.295). At 6 months of radiotherapy, in ARM A, seven patients (35%) and, in ARM B, five patients (25%) had severe restriction (P value = 0.681).

Conclusion:

We observed that 3DCRT is comparable to IMRT in terms of lung toxicity in esophageal cancer patients as proven from clinical toxicity data. More follow-up is required to see the chronic changes and overall survival.
Incidental finding of diffuse Tc-99m methylene diphosphonate uptake in lungs in a patient with renal insufficiency and lymphoma
Authors: Koç Zehra P. , Özcan Pınar P. , Balcı Yüksel , Sayar Hamide , Turgutalp Kenan
Published: December 2024

Metastatic calcification of the lungs is presented with increased Tc-99m methylene diphosphonate (MDP) accumulation which was reported previously in usually benign causes including pneumonia and renal insufficiency. F-18 Fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) is the gold standard imaging modality in staging of the lymphoma and an accurate modality in showing dissemination of the disease. This case report presents a patient with primary unknown tumor presented by lythic bone metastasis in F-18 FDG PET/CT and increased Tc-99m MDP accumulation in both lungs due to the renal insufficiency in bone scintigraphy who was diagnosed as lymphoma by lymph node biopsy results.
Impact of immobilization devices on the inter-fractional setup error and planning target volume for pelvic radiation therapy
Authors: Agarwal Priyanka , Upadhyay Neeraj , Agarwal Jaiprakash , Nanda Sambit S. , Ajay GV , Mukherjee Ashutosh , Pradhan Satyajit
Published: December 2024

Objectives:

To assess inter-fractional setup errors for patients undergoing pelvic radiation therapy and to determine the optimal immobilization devices, we compared the margins between the clinical target volume and planning target volume while using full immobilization devices, partial immobilization devices, and no immobilization devices in terms of systematic and random errors.

Materials and Methods:

The study was retrospectively conducted at a tertiary care facility and involved three groups of patients. Group A did not use immobilization devices but instead used a knee rest and a U-shaped pillow for patient comfort during the simulation. Group B used a partial-immobilization configuration with an all-in-board (AIO) base plate, a neutral neck rest (NNR), and a knee rest during the simulation. The final group, Group C, used immobilization devices including an AIO baseplate and Vac-lok with NNR during the simulation. All three groups of patients were positioned in a head-first supine position with arms up. The departmental IGRT protocol was followed, with kV CBCT acquired for the first three consecutive days and twice-weekly kV-CBCT imaging for the remaining fractions. Translational displacements, systematic errors, and random errors were calculated for all patients. The CTV to PTV margins were then calculated using the well-known margin recipe Van-Herk formula.

Results:

The study included 125 patients receiving pelvic radiation therapy, and 1297 kV-CBCT images were analyzed. The estimated CTV to PTV margin was lower in Group C patients for all three directions, AP, ML, and CC. However, Group B setup errors were observed slightly more in all three directions than in Group C patients. The largest CTV to PTV margin was found to be 7.1 mm in the ML direction for Group A patients.

Conclusion:

To improve setup reproducibility and patient comfort while minimizing errors in all three directions, we recommend using a partial immobilization setup for patients receiving pelvic radiation therapy.
ALDH1 Immunohistochemical expression and its association with tumor budding in oral squamous cell carcinoma of gingivobuccal complex
Authors: Bhatta Archana , Das Surya Narayan , Rath Rachna , Sethi Debashis , Pattnaik Bodhiswata , Mishra Sourav
Published: December 2024

Background:

Aldehyde dehydrogenase 1 is a potential biomarker for cancer stem cells (CSCs), pertinent to tumorigenesis and treatment resistance, whereas tumor buds (TB) are small nests of tumor cells scattered in the stroma of tumor front. This study evaluated the interrelationship of TBs with CSCs in oral squamous cell carcinoma (OSCC) cases of gingivobuccal complex.

Methods:

An immunohistochemical study was conducted on paraffin-embedded sections of 50 cases of OSCC of gingivobuccal complex with Pan-CK for TB and ALDH1 for CSCs. Correlations were assessed between the semiquantitative scoring for immunohistochemical expression of ALDH1 and tumor budding intensity. Statistical evaluation was performed by the Chi-square test, and cutoff score was determined by employing ROC curve.

Results:

A significant correlation of ALDH1 expression was attained between the groups both inside (P = 0.031) and outside (P = 0.028) the budding area, reflecting a spatial distribution of CSCs in the tumor front. The ROC curve analysis suggested a cutoff value of 11%-50% ALDH1 expression inside TB area, demonstrating 76% of sensitivity and specificity of 63%, which may better predict aggressive behavior and poorer prognosis than TB alone in OSCC.

Conclusion:

ALDH1 expression inside and outside the budding area correlated significantly with TB intensity, suggesting that TBs have CSCs-like phenotype predisposing to migratory and invasive properties.
Immunomodulatory Treatment and Outcome of Seropositive Autoimmune Encephalitis Children in Resource-Poor Settings
Authors: Kamate Mahesh , Patel Taiseenub
Published: December 2024

Abstract

Background:

Autoimmune encephalitis (AIE) is emerging as an important cause of acute encephalitis in children. It is treated with a combination of both pulse methylprednisolone (MP) and intravenous immunoglobulin as first line and either rituximab or cyclophosphamide in severe cases or those who do not respond. Due to financial constraints, all children do not receive intravenous immunoglobulin in most resource poor-settings but still improve. We here present our data from a resource-poor setting on the treatment of AIE.

Materials and Methods:

A retrospective chart review of all seropositive cases seen in the last years with focus on treatment and outcome was done.

Results:

Eight out of 70 suspected AIE children had positive NMDAR antibodies. Five out of eight responded to pulse MP alone with good outcome and no relapse over the next 2 years.

Conclusion:

The majority of children with AIE do not need both MP and immunoglobulins. Pulse MP alone suffices in many especially when diagnosed early.
Serum Leptin level in obese adolescents with metabolic syndrome: An experience of a tertiary care center of Bangladesh
Authors: Mahbuba Sharmin , Ferdosh Taslima , Moni Mst. Umme Kulsum , Habib Samira Humaira
Published: December 2024

Background:

High leptin level is associated with childhood obesity-related comorbidities including metabolic syndrome (MS).

Objective:

We aimed to find out serum leptin level in obese adolescents with MS.

Materials and Methods:

This prospective study was conducted in the Department of Pediatrics, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh, from November 1, 2022, to October 31, 2023, including 60 obese adolescents aged 10–16 years as cases and 25 nonobese adolescents as control. Serum leptin level was compared between those two groups and in adolescents with or without MS.

Analysis:

The data were analyzed by Statistical Package for Social Sciences computer software version 22 using unpaired Student’s t test, Chi-square test, Pearson’s correlation, and linear regression analysis. A P value of <0.05 was considered statistically significant.

Results:

Serum leptin level was significantly higher (P = 0.004) in obese adolescents than in the control group. MS was found in 63.3% of obese adolescents, and the leptin level was significantly higher among them (P = 0.000). It was significantly related to waist circumference (P = 0.000), both systolic blood pressure (P = 0.010) and diastolic blood pressure (P = 0.000), blood sugar level 2 h after glucose administration (P = 0.000), triglyceride (P = 0.000) and high-density lipoprotein level (P = 0.026). In the multivariate analysis, no determinant factor was found.

Conclusion:

Serum leptin levels are higher in obese adolescents having MS.
Early Markers of Chronic Kidney Disease Among Children in Steady-state Sickle Cell Anemia in Rivers State, Southern Nigeria: A Comparative Study
Authors: Briggs Datonye Christopher , Josiah Appollus , Omunakwe Hannah , Okechukwu Chioma , Okoh Dorathy , Amadi Ijeoma , Dublin-Green Linda Anucha
Published: December 2024

Aim:

We aimed to determine the status of early markers of chronic kidney disease (CKD) among children with steady-state sickle cell anemia (SCA) in southern, Nigeria.

Materials and Methods:

This comparative cross-sectional study randomly enrolled 60 hemoglobin SS-genotype (HbSS, SCA group) and 60 hemoglobin AA-genotype (HbAA, non-SCA group) children and their markers of early CKD were compared. Microalbuminuria was defined as spot urine albumin–creatinine ratio 30–<300 mg/g, hyperfiltration was glomerular filtration rate (GFR) ≥2 standard deviations from the mean estimated GFR for the non-SCA group and steady-state SCA was the absence of infection, pain, acute clinical symptoms, or crisis for ≥3 months.

Results:

Of the 120 children studied, 62 (51.7%) were males. The mean age was 9.36 ± 4.06 years (range: 3–16 years). The markers of CKD were higher in the SCA group than in the non-SCA group: Hyperfiltration (HbSS 25.0% vs. HbAA 6.7%, P = 0.002) and microalbuminuria (HbSS 16.7% vs. HbAA 3.3%; P = 0.015), respectively. The SCA group had four [adjusted odds ratio (AOR) = 4.67; 95% confidence interval (CI) = 1.44–15.04] and five (AOR = 5.80; 95% CI = 1.29–26.03) times increased odds of hyperfiltration and microalbuminuria compared with the non-SCA group. Hypertension was significantly higher among the non-SCA group than that of the SCA group (HbAA 16.7% vs. HbSS 1.7%; P = 0.004).

Conclusions:

The early markers of CKD are notably higher among children with SCA disease in southern Nigeria even during periods of apparent health. Therefore, early screening to identify subclinical CKD in our setting is necessary.
Vitamin D: A Role Beyond Rickets
Authors: Sultana Nadira , Roy Ranjit Ranjan , Kamal Mostafa , Ray Ashis
Published: December 2024

Beyond its classical role in calcium metabolism and bone health, vitamin D serves numerous non-classical functions crucial for overall well-being. It modulates immune function, influencing both innate and adaptive immunity, thereby aiding in the prevention of infections and autoimmune diseases. Vitamin D also plays a role in regulating cellular growth and differentiation, impacting processes such as cell proliferation and apoptosis, which are essential for maintaining tissue homeostasis and preventing cancer development. Additionally, emerging evidence suggests its involvement in cardiovascular health, insulin secretion, and neurological function. These non-classical functions highlight the importance of adequate vitamin D levels for overall health beyond bone strength.
Extreme value analysis of meteorological parameters observed during the period 1994–2022 at Kakrapar Gujarat site
Authors: Nankar D. P. , Patra Akhaya Kumar , Saradhi I. V. , Kumar A. Vinod
Published: December 2024

Extreme meteorological parameters plays an important role, for the selection of any civil structure at nuclear site or to design important nuclear structures to withstand design basis values of meteorological extremes that are likely to occur during the lifetime of these structures. An attempt was made to study the extreme value analysis of meteorological parameters observed during the period 1994 to 2022 at Kakrapar Gujarat Site. Meteorological parameters such as extreme rainfall (mm) (yearly, monthly and daily), extreme surface ambient temperature (°C), minimum relative humidity (%), extreme atmospheric pressure (mbar) and extreme hourly wind speed (km.h-1) for two levels of measurement (10m and 30m height) are evaluated and described in this paper. The maximum and the minimum rainfall in a year was found to be 2278 mm and 772 mm, respectively. The maximum and minimum ambient temperature and atmospheric pressure was 44.6 °C, 2.2 °C and 1023 mbar and 987 mbar, respectively. The maximum hourly wind speed at 10 m and 30 m height was found to be 42.5 km.h-1 and 58.3 km.h-1, respectively. The extreme value analysis reveals that the variables for maximum annual rainfall, maximum ambient temperature, maximum atmospheric pressure, maximum hourly wind speed at 10m and at 30m height obey Fisher-Tippette type I distribution, whereas minimum annual rainfall, maximum monthly rainfall, maximum daily rainfall, minimum ambient temperature, minimum relative humidity, and minimum atmospheric pressure obey Fisher-Tippette type II distribution. The design basis values corresponding to return periods of 50, 100, 200 and 500 years are derived and also reported in this paper.
Dose uniformity evaluations for gamma radiation processing facility using Monte Carlo simulations and its validation
Authors: Rajput Raksha , Garg Jyoti , George Jain Reji , Khedkar Kalpana , Jothish P. K. , Jayachandran N. , Mukherjee Pradip
Published: December 2024

The gamma radiation processing facilities (GRAPFs) qualify to obtain the license of operation on the basis of the radiological safety of the facility and the accurate radiation dosimetry in the product. The theoretical dose evaluations in the product are carried out using Monte Carlo simulations in this work. This is required for optimizing the source loading configuration with the best combination of averaged dose rate and dose uniformity ratio (DUR) to maximize the efficiency of the facility. Three different GRAPFs are chosen for the study. The theoretical results of DUR are validated against the commissioning dosimetry with a variation of <10% for the facilities chosen. The simulation tool used is an efficient tool for dose mapping studies of radiation processing facilities of different designs.
Attitude of caregivers, psychiatrists, and nurses toward coercive measures: An observational, survey-based comparative study
Authors: Kulkarni Sneha , Sankar M. Uma , Dabbiru Ravi Kumar , Reddy Ramsubba , Rao Sireesha Srinivasa , Nasirabadi Minhajzafar
Published: December 2024

Objectives:

The primary objective was to compare the attitude of health-care providers (psychiatrists and nursing staff) and caregivers.

Materials and Methods:

This prospective, survey-based study used the Staff Attitude to Coercion Scale, Morisky Medication Adherence Rating Scale, Oslo Social Support Scale, and the Modified Overt Aggression Scale.

Results:

Participants (326) included psychiatrists (32.51%), staff nurses (35.58%), and caregivers (31.90%). Health-care professionals scored higher in offense and safety subscale (psychiatrists 3.2 and 5.55; nurses 3.12 and 5.65) compared to caregivers (2.46 and 5.10). In coercion as treatment subscale, caregivers scored least (0.78) (psychiatrists 1.15, nurses 1.92). The difference in these subscales was statistically significant (P = 0.001). There was no significant influence of social support and level of education of caregivers on the use of physical restraint. Of 104 patients, 58.65% were brought with physical restraint. Treatment compliance (n = 85) in stabilized patients was 84.7%.

Conclusion:

According to health-care providers, the use of coercion was offensive; coercion can be reduced by improving the resources and giving more personal time. All groups acknowledged that coercion infringes on patients’ human rights but supported its use when necessary for ensuring patient care and safety in the environment.
A case report on Charles bonnet syndrome in a patient with age-related macular degeneration
Authors: Pavani Angati
Published: December 2024

Our objective is to report and discuss a rare (under-recognized) case of visual release hallucinations also known as Charles Bonnet syndrome (CBS). Usually, it spontaneously resolves within a few years in most cases. Most patients who experience hallucinations as part of CBS are not bothered by the symptoms and, hence, are not candidates for pharmacological treatment. Recognizing a patient’s report of visual hallucinations as a symptom of vision impairment can avoid misdiagnosis, unnecessary investigation, and possible mismanagement. The patient was treated with tablet risperidone and was reassured that his visual hallucinations might be due to his eye disease and thus was not real. Although there was no improvement in hallucinations, he did not report the hallucinations to be as distressing as before and gained the capacity to live with his continuing visual hallucinations with no need for medications. This case report highlights the importance of counseling in CBS about the nature of the hallucinations.
Comparative study of soft neurological signs in patients of schizophrenia and bipolar disorder at a tertiary care center
Authors: Sadula Ravi Kishore , Meda Aparna , Kesavareddy Sudharani , Molanguri Umashankar
Published: December 2024

Background:

The study of neurological soft signs (NSSs) is a simple, clinical, inexpensive, and direct method of investigation for schizophrenia and bipolar disorders which are the major mental health problems that require early detection and treatment. Therefore, it is important to establish whether NSS is a common feature of schizophrenia and bipolar Disorder. This study was undertaken to study and compare the presence of NSSs in patients with schizophrenia and bipolar disorder.

Aim:

This study aims to compare the NSSs in patients of schizophrenia and bipolar disorder.

Methodology:

A cross-sectional study with a sample size of 80 patients (40 patients in each group) was taken as per the International Classification of Diseases-10 (ICD-10) criteria. The evaluation of NSSs was done using the Cambridge neurological inventory (CNI) and compared on three domains of CNI. The level of significance was set at 0.05 for all statistical analysis.

Results:

On CNI part 1, mean scores of schizophrenia and bipolar disorder are 31.91 and 28.90 respectively t = 3.122. (P = 0.003). On CNI part 2 of mean scores of schizophrenia and bipolar disorder are 47.05 and 38.05, respectively, t value is 6.685 (P < 0.001) On CNI part 3, mean scores of schizophrenia and bipolar disorder are 44.68 and 58.25, respectively, t value is 6.235 (P < 0.001).

Conclusion:

NSSs especially repetitive movement sensory integration, impairment of motor coordination were more in schizophrenia, whereas other signs such as posturing, motor movements were more in bipolar disorder patients in our study.
A cross-sectional study of personality traits using neuroticism, extraversion, and openness five-factor inventory in patients with alcohol dependence in a tertiary hospital setting
Authors: Preetinanda Pallavi , Singisetti Srinivas , Garapati Abhilash , Sanapala Vidya , Vasireddy Niveditha , Nukala Srikrishna , Tata Ramya Spandana , Kumar Santhosh
Published: December 2024

Background:

Personality traits have not only been identified as risk factors for the onset and maintenance of alcohol use disorders but also as a significant predictor of alcohol-related dysfunction and comorbidity when tested with multifactorial models. The five-factor model of personality is popular as it explains a good deal of the variance in the personality profiles of different individuals. The study aimed to assess the personality traits of patients with alcohol dependence using neuroticism, extraversion, and openness five-factor inventory (NEO-FFI) and to determine its association with various alcohol-related variables, dysfunction, and comorbidities.

Methodology:

Fifty patients with alcohol dependence, aged 18–65 years, in a hospital outpatient and inpatient settings, were evaluated using a semi-structured sociodemographic pro forma and the 60-item NEO-FFI-3.

Results:

Patients with alcohol dependence had high scores on neuroticism and low scores on agreeableness and conscientiousness. High scores on neuroticism and extraversion and low scores on agreeableness and conscientiousness were associated with higher alcohol variable scores, dysfunction, and comorbidities.

Conclusion:

Higher neuroticism and extraversion and lower agreeableness and conscientiousness scores are associated with parameters associated with higher severity of alcohol dependence and its complications.
Effects of Engine Performance Parameters and Vibration Level of the Engine Block Operated with Gasoline and Ethanol Fuel
Authors: Santana Claudio Marcio , Santana Linicker Lopes Bruno , Almeida Helder Giostri Alves
Published: December 2024

In recent years, the use of ethanol fuel in internal combustion engines has gained importance due to environmental and commercial factors, since ethanol produces lower emission rates at similar performance parameters compared to gasoline fuel. The objective of this study is to evaluate and compare the effects of engine performance parameters on the vibration level of the engine block operated with gasoline and ethanol fuel. The experimental tests consisted of operating an Otto cycle engine on a bench dynamometer under full load conditions varying rotation and correlating the vertical, longitudinal and transverse vibration levels of the block engine with the engine performance parameters. The results showed that the engine vibration level was influenced by engine speed, load, type of fuel and performance parameters of the engine. The combustion process is primarily responsible for the highest level of vibration reached when using ethanol as a fuel. Under all operating conditions, the vibration level of the engine block was highest when using ethanol compared to the engine run on gasoline. On average, the transverse engine vibration was higher than vertical and longitudinal engine vibration. This study holds relevance as it correlates the longitudinal, vertical and transverse vibration level of the block of an internal combustion engine, as is found in an engine combustion process fueled by ethanol and gasoline.
Ground Height and Pitch Angle Influence on the Aerodynamic Behavior of a Production Pickup Truck
Authors: Buscariolo Filipe Fabian , Terra Rafael Tedim
Published: December 2024

The fuel economy performance of road vehicles is one of the most important factors for a successful project in the current automotive industry due to greenhouse effect gases reduction goals. Aerodynamics and vehicle dynamics play key roles on leading the automaker fulfill those factors. The drag coefficient and frontal area of the vehicle are affected by several conditions, where the ground height and pitch angle are very relevant, especially for pickup trucks. In this work, we present a combined study of suspension trim heights and aerodynamics performance of a production pickup truck, where three different loading conditions are considered. The three weight configurations are evaluated both in terms of ground height and pitch angle change considering the suspension and tires deflection and these changes are evaluated in terms of drag coefficient performance, using a Lattice-Boltzmann transient solver. Results are compared with the baseline vehicle at road speed condition, where both numerical results and flow comparison contours are provided.
Management Model Applied in an Auto Parts Industry: Decision Pyramid
Authors: Júnior Jairo José Modesto Gonçalves , Araujo Edgar Junior Alves , Teixeira Natália Siqueira
Published: December 2024

This work presents the elements that demonstrate the use of a new mental concept (mindset), a way of thinking and interacting with the most diverse corporate situations in an independent and mature way to act with the best decision for the business. Based on a decision model by a systemic logic that naturally seeks to become a habit, with applications in the most diverse situations, being applied in an auto parts industry in the Brazilian national market. By following a unique model of interaction, intervention and action in an organizational system, the interaction between decisions requires the sense of being the owner of the business, something that will be explored throughout the course of the application of the model, and demonstrating that this concept should be applied at all types of decision, including personal life.
Application of Servo-Assisted Technology in Commercial Vehicle Steering Systems for Autonomous Mobility in Off-Road Trucks. Case Study: Application on 8x2/8x4 Sugarcane Trucks
Authors: Oliveira Santos Neto Antídio , Lara Vanderlei , Silva Everton , Destro Daniel , Moura Márcio , Borges Felipe , Haegele Timo
Published: December 2024

The exponential growth of the agribusiness market in Brazil combined with the high receptivity among farmers of new technological solutions has driven the study and implementation of high technology in the field. This work aimed to apply servo-assisted driving technology to enable autonomous mobility in an off-road sugarcane truck responsible for harvesting sugarcane. The technology consists of a conventional hydraulic steering with a motor, ECU and torque and angle sensors responsible for reading input data converted from GPS signals and previously recorded tracking lines. The motor responsible for replacing 100% of the physical force generated by the driver acts in accordance with the required torque demand, and the sensors combined with the ECU correct the course to meet the follow-up line through external communication ports. The accuracy of the system depends exclusively on the accuracy of the GPS signal, in this case reaching 2,5 cm, which is considered extremely high accuracy when comparing available technologies. The proposal was assembled on a national vehicle with a capacity of 31t in an 8x4 configuration, duly modified to meet the effort demands on typical national grounds and validated in the field through special test circuits. The use of the technology proved to be highly satisfactory and allowed an increase in efficiency of up to 7,5% compared to the use of conventional technology.
Low-Level Data Fusion between Camera and Automotive RADAR for Vehicle and Pedestrian Detection Using nuScenes Database
Authors: Cury Hachid Habib , Teixeira Evandro Leonardo Silva , Silva Rafael Rodrigues
Published: December 2024

Autonomous driving technology has indeed become a focal point of research globally, with significant efforts directed towards enhancing its key components: environment perception, vehicle localization, path planning, and motion control. These components work together to enable autonomous vehicles to navigate complex environments safely and efficiently. Among these components, environment perception stands out as critical, as it involves the robust, real-time detection of targets on the road. This process relies heavily on the integration of various sensors, making data fusion an indispensable tool in the early stages of automation. Sensor fusion between the camera and RADAR (Radio Detection and Ranging) has advantages because they are complementary sensors, where fusion combines the high lateral resolution from the vision system with the robustness in the face of adverse weather conditions and light invulnerability of RADAR, as well as having a lower production cost compared to the LiDAR (Light Detection and Ranging) sensor. Given the importance of sensor fusion for automated driving, this paper examines the low-level sensory fusion method that uses RADAR detection to generate Regions of Interest (ROIs) in the camera coordinate system. To do so, it was selected a fusion algorithm based on RRPN (Radar Region Proposal Network), which combines RADAR and camera data, and compared it to Faster R-CNN, which uses only camera data. Our goal was to study the advantages and limitations of the proposed method. We explored the NuScenes database to determine the best aspect ratios for different object sizes and modified the RRPN algorithm to generate more effective anchors. For training, we used camera and frontal RADAR data from the NuScenes database. The COCO dataset metrics under three different temporal conditions: day, night, and rain was used to evaluate the proposed models.
Experimental Investigation of the Potential of Hydrogen as an Alternative to Brazilian Commercial Diesel Fuel in Current Heavy-Duty Fleet
Authors: Assis Guilherme , Sánchez Fernando Zegarra , Braga Sergio Leal , Pradelle Renata Nohra Chaar , Souza Junior Jorge , Pradelle Florian , Ticona Epifanio Mamani
Published: December 2024

Mobility in Brazil, dominated by road transportation, is responsible for consuming around a third of the energy matrix and for emitting approximately half of the energy-related emissions in the country. Among the alternatives to reduce its greenhouse gas emissions, the use of low-carbon hydrogen has a strong potential for decarbonization and improvement of engine efficiency. Thus, this study experimentally investigated the partial replacement of commercial diesel (with 12% of fatty acids methyl esters (FAME) biodiesel) by hydrogen in a commercial vehicle equipped with a compression-ignition internal combustion engine. To investigate the effects of this substitution on performance and emission profile, the vehicles was adapted for dual-fuel operation and hydrogen was injected together with air into the MB OM 924 LA engine of a Mercedes-Benz Accelo 1016 vehicle. Tests were carried out on a chassis dynamometer with 0%, 2% and 4% slope and at speeds equal to 50, 60 and 70 km/h to simulate various loads. For each of these combinations, commercial diesel was replaced by hydrogen with hydrogen energy share of 0%, 2%, 4%, 6%, 8% and 10%, respectively. The results showed that replacing commercial diesel with hydrogen resulted in a relative reduction of up to 17.6% in CO2 emissions, 13.7% in CO and 25.5% in THC. However, the results of the performance parameters showed no improvement in efficiency under the tested conditions, with a reduction of up to 20.8% in thermal efficiency and an increase of up to 26.3% in specific fuel consumption. In conclusion, with minimal alterations, the results obtained with a commercial vehicle demonstrated the feasibility of hydrogen as a promising alternative fuel for use in compression ignition engines in the current fleet to reduce emissions.
A Multibody Dynamics Approach to Assess Auto Pull Behavior of Gear Shift System
Authors: Sabri Salah Ahmad , Bhimrao Sachin Ahirrao , Pinto João Paulo , Mussulini Bruno C , Dias Sebastião Joel
Published: December 2024

Gear shift system in a gearbox is used to shift the power flow from one gear set to another gear set which enables manual transmission to maintain different torque and speed combination. Shift quality is determined by the response of the gear shift lever while changing the gears. Shift force over the entire travel event of engagement and disengagement for multiple gear sets is the key factor influencing gear shift quality. If the shift forces are higher, the effort required for shifting will also increase resulting in uncomfortable shifting. On the other hand, with lower shifting force, sudden jerk, vibration or change in vehicle condition may also cause shifting which is undesirable and may lead to safety issue. One of the important features of shift system is auto pull behavior observed while shifting. While shifting, driver starts displacing the shift lever and after threshold point the transmission itself pulls the shift lever to the end point, reducing driver effort. In the present study multibody dynamic (MBD) approach is used to evaluate auto pull behavior of gear shift system. Detailed rigid body dynamic modelling of the gear shift system along with its subsystems, power trains is developed in the virtual environment. Different geometric and non-geometric parameters affecting the auto pull behavior of shift system are studied. The results from MBD analysis are correlated with analytical calculation and validated with experimental measurement. Virtual engineering approach helps in establishing the design parameters and their optimization through use of simulation methodology even before physical prototype is built and thus reduces the prototype building and testing cost. This study can further be utilized to automate the design process as per shift system requirement.
Optimization of a 2-D Multi-Element Rear Wing on a Formula 1 Car
Authors: Souza Dourado Guilherme , Hayashi Marcelo Tanaka
Published: December 2024

The aerodynamic force produced by external flows over two-dimensional bodies is typically decomposed into two components: lift and drag. In race cars, the lift is known as downforce and it is responsible for increasing tire grip, thereby enhancing traction and cornering ability. Drag acts in the direction opposite to the car’s motion, reducing its acceleration and top speed. The primary challenge for aerodynamicists is to design a vehicle capable of producing high downforce with low drag. This study aims to optimize the shape of a multi-element rear wing profile of a Formula 1 car, achieving an optimal configuration under specific prescribed conditions. The scope of this work was limited to a 2-D model of a rear wing composed of two 4-digit NACA airfoils. Ten control parameters were used in the optimization process: three to describe each isolated profile, two to describe their relative position, and two to describe the angles of attack of each profile. An optimization cycle by finite-differences was implemented, with the figure of merit being the maximization of the lift coefficient. In order to save computational effort, the viscous formulation was just used after obtaining an optimal design for inviscid flows. Besides, the turbulence model adopted in this work was the Spalart-Allmaras. Compared to the initial configuration, the optimized one showed significant improvements in aerodynamic performance, with increased downforce and reduced drag coefficient.
Automation of a Quarter-Car Suspension Test Bench
Authors: Siqueira Matheus Amaral , Gomes Pedro Carvalho , Teixeira Evandro Leonardo Silva , Fortaleza Eugênio Libório Feitosa , Morais Marcus Vinicius Girão
Published: December 2024

This paper aims to describe a quarter-car suspension test bench automation process to be utilized in an academic environment. The project is made up of pneumatic system modeling and control system design. An analysis of the bench’s pneumatic system is carried out. This pneumatic system is composed of a pneumatic actuator and a proportional directional control valve, which are responsible for generating the road profile. It is proposed a model to compensate the non-linearities present in the pneumatic system measurement process and the disturbances caused by the under test suspension system, as well as a control strategy for small displacements of the load through linear control approaches, which provide the necessary flexibility to directly influence the parameters affecting the dynamics of the excitation system platform’s displacement, thereby reducing the complexity of the controller design to be adopted. Furthermore, analyses are conducted on the effectiveness of the control in generating sinusoidal track profiles for a frequency range between 0 and 5 Hz, where the repeatability of this process and the safety of the electrical and mechanical components of the test bench are observed. Numerical results, obtained through the excitation system control of the quarter-car suspension test rig, have shown success in generating sinusoidal road profiles, which allows it to investigate and develop suspension systems based on the quarter-vehicle model.
Hydrogen as a Fuel Cell: A Comparative between the Gas and Liquid State and Storage
Authors: Alves Joyce , Silva Antônio , Paterlini Bruno , Santos Felipe , Pedroso Henrique , Henrique Pedro , Milani Pedro
Published: December 2024

It is emerging the need to take action to reduce the greenhouse effect, which is one of the major causes of climate change and environmental disasters that has been occurring frequently in recent decades throughout the planet. The burning of fossil fuels for electricity and energy generation are the main concerns and those that have greater incentives for its reduction, as its by-product of the reaction of burning CO2, which among the greenhouse gases is primarily responsible for its aggravation.

The transport sector excels in CO2 emissions, emits about 20% of gas, according to the Intergovernmental Panel on Climate Change (IPCC), a scientific organization linked to the United Nations (UN). A promising solution to reduce the impact of this sector would be the use of hydrogen fuel cell, which if carried out through renewable energies, the electrolysis of hydrogen has zero CO2 emission throughout the cycle. However, one of the biggest challenges to make viable the use of hydrogen as fuel is its storage due to its being very volatile in its gaseous form and necessary to be kept at low temperatures in its liquid form.

In this paper we will explain briefly about the generation cycle of the hydrogen cell in its two forms and put into perspective the physical-chemicals for their storage and use together with the technologies currently used and possible future technologies.
Experimental Determination of the Residual Torque Range in a Plastic Connector of the Fuel Pump Module at End of Life
Authors: Spitaletti Laís Scotelari , da Fonseca Márcio Ghiraldelli
Published: December 2024

The study of residual torque is necessary in various fields to ensure the safety and reliability of bolted joints.

The present study aims to determine, experimentally, the decrease in torque applied to a nut used in the assembly of two polymeric components (POM - Polyoxymethylene). These components are part of the fuel supply module, responsible for supplying fuel from the tank to the engine. This reduction in torque initially applied is mapped to the end-of-life of the components and is used as an approval criteria in the audit procedures of the Robert Bosch company. The first component features an overmolded metallic screw, injected into POM. The mating part is also injection molded from POM and is assembled onto the first part, secured by tightening a metal nut. Due to the plastic-to-metal interface, it’s expected that there will be a reduction in the initially applied torque required to fasten the pieces together.

The study was based on 5 steps:

1
Theoretical study on residual torque at the plastic-to-metal interface;

2
Verification of plastic component deformation due to applied torque;

3
Assembly of samples for practical tests;

4
Mapping of torque decrease in samples by time. In this case, a digital torque wrench was used;

5
Analysis of the data and determination of the residual torque range at the end of the product’s life.

After the study was completed, it was determined a minimum residual torque, for the end of the product’s life, in this application. This criterion enables more accurate control in field part verification, improves product quality, and optimizes failures identification.
Experimental Investigation of Spray Characteristics Direct Injected in Atmospheric Ambient Conditions by a Multi-Hole Injector
Authors: Guzzo Márcio Expedito , Fonseca Lucas Guimarães , Duarte Thales Henrique Ramos , Baeta José Guilherme Coelho , Huebner Rudolf , Pujatti Fabrício José Pacheco
Published: December 2024

The aim of the present work was to characterize macroscopic spray parameters of a multi-hole direct injection injector for spark ignition engine applications. The geometry, the position of spray boundaries the overall cone angle, the spray vertical penetration and the vertical spray length were evaluated by processing the spray images recorded at 3300 frames per second. The frequency of recording images was suitable for capturing all the spray developments in all tested conditions. The tested fluid was EXXSOL D60 for simulating ethanol spray characteristics due to its similar properties and due to security reasons. The injector was tested outside the engine and into an open acrylic chamber being injected into atmospheric air conditions of the laboratory. The injection pressure was set up in 100 bar and the simulated engine speed were set up in MOTEC ECU in 3000 rpm, 3600 rpm and 4000 rpm. The injection durations were set up in 3,0 ms for 3000 rpm and 2.3 ms for 3600 rpm and 4000 rpm. The spray vertical lengths and the spray vertical penetrations were coincident and consequently showed same results in the period when the injector was discharging the tested fluid. The results showed that after the end of spray injections the spray penetration kept increasing normally while the spray vertical length decreased immediately after the end of injections and after this rapid decrease it continued the increasing behavior. No significant differences were found in cone angle, vertical penetrations, vertical spray length and spray overall cone angle when the simulated engine speed was varied.
Assessing Road Load Predictions: A Comprehensive Review and Comparative Analysis of Real-World versus Numerical Simulation
Authors: Pereira Leonardo Pedreira , Braga Sérgio Leal
Published: December 2024

Road loads, encompassing aerodynamic drag, rolling resistance, and gravitational effects, significantly impact vehicle design and performance by influencing factors such as fuel efficiency, handling, and overall driving experience. While traditional coastdown tests are commonly used to measure road loads, they can be influenced by environmental variations and are costly. Consequently, numerical simulations play a pivotal role in predicting and optimizing vehicle performance in a cost-effective manner. This article aims to conduct a literature review on road loads and their effects on vehicle performance, leveraging experimental data from past studies from other researchers to establish correlations between measured road loads and existing mathematical models. By validating these correlations using real-world measurements, this study contributes to refining predictive models used in automotive design and analysis. The simulations in this study, utilizing five distinct empirical correlations, demonstrated strong alignment with actual track test results, with coefficients of determination (R2) ranging from 0.84 to 0.97.
Combustion Visualization in Commercial Engines Operating with Diesel-Biodiesel Blend
Authors: Ferreira Bruno Eustáquio Pires , Moreira Vinícius Guerra , Borges Débora Maria de O. , Morais Hanriot Sérgio
Published: December 2024

The Brazilian government encourages the use of renewable fuels in diesel engines through resolutions that define the mandatory addition of biodiesel to automotive diesel oil. The use of biodiesel will reach 15% by 2026. Due to this change in the physicochemical characteristics of commercial fuel, there is a need to deepen studies regarding the combustion process and the effects of this change on engine performance and emissions. With technological advancements, one of the viable techniques for this purpose is high-speed imaging to assess combustion within the cylinder. This paper presents the methodology for constructing a system that allows high-speed imaging, using a high-speed camera, of the combustion process of an MWM 229/4 engine. Other studies published in this area typically involve capturing images inside the cylinder once per cycle and advancing the angular position of capture each cycle. This paper proposes a more refined method, where images are acquired every 2.5°CA, allowing for the observation of a sequence of images from the same cycle. As a result, the images captured in one of the cylinders are presented, in which one can observe the evolution of combustion synchronized with the in-cylinder pressure curve.