bluuebunny/crossref_metadata_2025 huggingface dataset:
Pathogenesis and Surgical Treatment of Congenitally Corrected Transposition of the Great Arteries (ccTGA): Part III
Authors: Zubrzycki Marek , Schramm Rene , Costard-Jäckle Angelika , Morshuis Michiel , Grohmann Jochen , Gummert Jan F. , Zubrzycka Maria
Published: September 2024

Congenitally corrected transposition of the great arteries (ccTGA) is an infrequent and complex congenital malformation, which accounts for approximately 0.5% of all congenital heart defects. This defect is characterized by both atrioventricular and ventriculoarterial discordance, with the right atrium connected to the morphological left ventricle (LV), ejecting blood into the pulmonary artery, while the left atrium is connected to the morphological right ventricle (RV), ejecting blood into the aorta. Due to this double discordance, the blood flow is physiologically normal. Most patients have coexisting cardiac abnormalities that require further treatment. Untreated natural course is often associated with progressive failure of the systemic right ventricle (RV), tricuspid valve (TV) regurgitation, arrhythmia, and sudden cardiac death, which occurs in approximately 50% of patients below the age of 40. Some patients do not require surgical intervention, but most undergo physiological repair leaving the right ventricle in the systemic position, anatomical surgery which restores the left ventricle as the systemic ventricle, or univentricular palliation. Various types of anatomic repair have been proposed for the correction of double discordance. They combine an atrial switch (Senning or Mustard procedure) with either an arterial switch operation (ASO) as a double-switch operation or, in the cases of relevant left ventricular outflow tract obstruction (LVOTO) and ventricular septal defect (VSD), intra-ventricular rerouting by a Rastelli procedure. More recently implemented procedures, variations of aortic root translocations such as the Nikaidoh or the half-turned truncal switch/en bloc rotation, improve left ventricular outflow tract (LVOT) geometry and supposedly prevent the recurrence of LVOTO. Anatomic repair for congenitally corrected ccTGA has been shown to enable patients to survive into adulthood.
Subsequent Vaccination against SARS-CoV-2 after Vaccine-Induced Immune Thrombotic Thrombocytopenia
Authors: Uzun Günalp , Ringelmann Theresa , Hammer Stefanie , Zlamal Jan , Luz Beate , Wolf Marc E. , Henkes Hans , Bakchoul Tamam , Althaus Karina
Published: September 2024

Background: Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a rare but severe complication following vaccination with adenovirus vector-based COVID-19 vaccines. Antibodies directed against platelet factor 4 (PF4) are thought to be responsible for platelet activation and subsequent thromboembolic events in these patients. Since a single vaccination does not lead to sufficient immunization, subsequent vaccinations against COVID-19 have been recommended. However, concerns exist regarding the possible development of a new thromboembolic episode after subsequent vaccinations in VITT patients. Methods: We prospectively analyzed follow-up data from four VITT patients (three women and one man; median age, 44 years [range, 22 to 62 years]) who subsequently received additional COVID-19 vaccines. Platelet counts, anti-PF4/heparin antibody level measurements, and a functional platelet activation assay were performed at each follow-up visit. Additionally, we conducted a literature review and summarized similar reports on the outcome of subsequent vaccinations in patients with VITT. Results: The patients had developed thrombocytopenia and thrombosis 4 to 17 days after the first vaccination with ChAdOx1 nCoV-19. The optical densities (ODs) of anti-PF4/heparin antibodies decreased with time, and three out of four patients tested negative within 4 months. One patient remained positive even after 10 months post first vaccination. All four patients received an mRNA-based vaccine as a second vaccination against SARS-CoV-2. No significant drop in platelet count or new thromboembolic complications were observed during follow-up. We identified seven publications reporting subsequent COVID-19 vaccination in VITT patients. None of the patients developed thrombocytopenia or thrombosis after the subsequent vaccination. Conclusion: Subsequent vaccination with an mRNA vaccine appears to be safe in VITT patients.
Comparison of High-Dose versus Low-Dose Trimethoprim–Sulfamethoxazole for Treating Pneumocystis jirovecii Pneumonia among Hemodialysis Patients: A Nationwide Database Study in Japan
Authors: Shuto Hisayuki , Omori Shota , Hiramatsu Kazufumi , Kadota Jun-ichi , Fushimi Kiyohide , Komiya Kosaku
Published: September 2024

Background: Hemodialysis patients are at high risk for developing Pneumocystis jirovecii pneumonia (PJP), and trimethoprim–sulfamethoxazole (TMP–SMX) is the first-line agent for treating this disease. However, there is a lack of consensus on the required dosage of TMP–SMX for hemodialysis patients. Methods: This study used the nationwide Japanese Diagnosis Procedure Combination database to review hemodialysis patients hospitalized for PJP from April 2014 to March 2022. Eligible patients were divided into high-dose and low-dose groups based on the median daily dose per body weight of TMP. The 90-day mortality and adverse events after propensity score matching were compared between the groups. Results: A total of 126 hemodialysis patients with PJP were included, and the median daily dose per body weight of TMP was 5.74 mg/kg/day (interquartile range: 4.33–8.18 mg/kg/day). Thirty-two pairs were analyzed after the propensity score matching. No significant differences in the 90-day mortality and proportion of adverse events were observed between the high-dose and low-dose groups. Conclusions: A high dose of TMP–SMX is unlikely to decrease the in-hospital mortality and adverse events among hemodialysis patients with PJP. However, the results should be interpreted with caution, given the lack of power and lack of long-term follow-up. Additional prospective interventional studies are required to validate these results.
Stratifying the Risk of Disease Progression among Surgically Treated Muscle-Invasive Bladder Cancer Eligible for Adjuvant Nivolumab
Authors: Flammia Rocco Simone , Tuderti Gabriele , Bologna Eugenio , Minore Antonio , Proietti Flavia , Licari Leslie Claire , Mastroianni Riccardo , Bove Alfredo Maria , Anceschi Umberto , Brassetti Aldo , Ferriero Maria Consiglia , Guaglianone Salvatore , Chiacchio Giuseppe , Calabrò Fabio , Leonardo Costantino , Simone Giuseppe
Published: September 2024

Background: Check-Mate 274 has demonstrated the disease-free survival (DFS) benefit of adjuvant nivolumab in surgically treated muscle-invasive bladder cancer (MIBC). Since immunotherapy represents an expensive treatment with potential side effects, a better understanding of patient-specific risks of disease progression might be useful for clinicians when weighing the indication for adjuvant nivolumab. Objective: To identify the criteria for risk stratification of disease progression among MIBC patients eligible for adjuvant nivolumab. Materials and methods: A single-institution, prospectively maintained database was queried to identify patients eligible for adjuvant nivolumab according to Check-Mate 274 criteria. To account for immortal bias, patients who died or were lost to follow-up within 3 months of undergoing a radical cystectomy (RC) were excluded. Kaplan–Meier and Cox regression analyses addressed DFS, defined as the time frame from diagnosis to the first documented recurrence or death from any cause, whichever occurred first. Regression tree analysis was implemented to identify criteria for risk stratification. Results: Between 2011 and 2022, 304 patients were identified, with a median follow-up of 50 (IQR 24–72) months. After multivariable adjustment, including NAC as a potential confounder, higher CCI (HR 1.56, 95%CI 1.10–2.21, p = 0.013), T stage (HR 2.06, 95%CI 1.01–4.17, p = 0.046), N stage (HR 1.73, 95%CI 1.26–2.38, p = 0.001) and presence of LVI (HR 1.52, 95%CI 1.07–2.15, p = 0.019) increased the risk of disease recurrence or death. Finally, a two-tier classification was developed. Here, five-year DFS rates were 56.1% vs. 18.1 for low vs. high risk (HR: 2.54, 95%CI 1.79–3.62, p < 0.001). Conclusions: The current risk classification, if externally validated on larger samples, may be useful when weighing the risk and benefit of adjuvant nivolumab treatment and making patients more aware about their disease and about the need for additional treatment after RC.
Comparison of the Minimally Invasive Reverdin–Isham Lateral Translation Osteotomy Versus the Standard Reverdin–Isham Technique: A Pilot Prospective Cohort Study
Authors: Belda-Donat Maria , Marti-Martinez Luis M. , Lorca-Gutierrez Rubén , Naranjo-Ruiz Carmen , Chacón-Giráldez Fernando , Barrios Carlos
Published: September 2024

Background/Objectives: Reverdin–Isham osteotomy is effective in correcting moderate hallux valgus deformity but has certain limitations when correcting a deformity in the sagittal plane. This study aimed to evaluate the impact on pain, functionality, and radiological measures of angular corrections, and the safety of the Reverdin–Isham lateral translation technique through minimally invasive surgery in the treatment of a moderate hallux valgus compared to Reverdin–Isham standard osteotomy. Methods: A pilot 6-month prospective cohort study was conducted on adults over 18 years old with a hallux valgus in at least one foot. The study exposure was the use of the Reverdin–Isham lateral translation technique. The outcome variables were pain and functionality through VAS and AOFAS scales, respectively, and radiological measurements of the first toe metatarsophalangeal angle (MPA), first space intermetatarsal angle (IMA), proximal articular set angle (PASA), distal articular set angle (DASA), metatarsal formula, and position of sesamoids in the AP projection. Results: The study involved 60 participants. Results indicate significant reductions in pain and radiological measures in both cohorts: MPA improved by 23.13 degrees, IMA by 5.93 degrees, and sesamoid position by 4.23 degrees in patients who underwent the lateral translation technique versus 13.20, 3.30, and 1.57 degrees, respectively, in patients who experienced the standard Reverdin–Isham technique. The lateral translation method showed greater reductions in these metrics compared to the standard Reverdin–Isham technique (p < 0.05). Conclusions: Percutaneous Reverdin–Isham techniques, both standard and with lateral translations, effectively corrected moderate hallux valguses. However, the lateral translation method provided greater reductions in MPA, IMA, and sesamoid positions, making it more suitable for deformities with IMAs over 15 degrees.
Retrospective Analysis of Clinicopathological Characteristics of Surgically Treated Basal Cell Carcinomas of the Face: A Single-Centre Maxillofacial Surgery Experience
Authors: Saeidi Abdullah , Gülses Aydin , Jamil Maryam , Alolayan Albraa , Elsayed Shadia , Wiltfang Jörg , Flörke Christian
Published: September 2024

Background: Basal cell carcinoma is the most common nonmelanoma skin cancer, followed by cutaneous squamous cell carcinoma. The objective of the current study was to retrospectively evaluate the epidemiology, characteristic variations, histological aspects, and prognosis of basal cell carcinoma of the facial region based on a single-centre experience. Methods: Data from 125 patients admitted to the Department of Oral and Maxillofacial Surgery, University Medical Center Schleswig-Holstein (UKSH), Kiel, for surgical treatment of basal cell carcinomas of the face between January 2015 and April 2021 were evaluated. Results: The mean patient age was 79.58 years, 60.5% were male and 39.5% were female. Six patients (4.8%) had tumour recurrence with no regional metastasis. Seventy-nine patients (63%) were classified as T1. The nose and the temporal region were the most common areas. The mean tumour thickness was 3.20 mm. Conclusions: Micronodular, sclerosing/morphoeic, nodular, and superficial growth patterns of basal cell carcinoma are highly correlated to recurrence, so an excision safety margin is recommended. There is a strong correlation between tumour thickness and recurrence among basal cell carcinoma cases. When completely excised, the recurrence rate for basal cell carcinoma is relatively low.
Cerebral Embolic Protection Devices: Are There Any Indications in Transcatheter Aortic Valve Replacement?
Authors: Sayah Neila , Skalidis Ioannis , Mesnier Jules , Neylon Antoinette , Akodad Mariama , Asgar Anita
Published: September 2024

Stroke following transcatheter aortic valve replacement (TAVR) is a significant and life-threatening adverse event. The vast majority of these incidents occur during the TAVR procedure or within the first 24 h following TAVR, with a notable prevalence of cerebral embolic events. In response to this concern, cerebral embolic protection devices (CEPDs) have been designed to mitigate the risk of peri-procedural ischemic stroke during TAVR. The primary objective of CEPDs is to diminish the intraprocedural burden associated with new silent ischemic brain injuries. Despite the development of several CEPDs, their clinical efficacy remains uncertain. In this review, we delve into a comprehensive analysis of the utilization of CEPDs in patients undergoing TAVR, exploring insights from the existing literature. Additionally, we aim to present future perspectives and discuss the clinical implications associated with the incorporation of CEPDs in TAVR procedures.
Anesthetic Approach for Non-Cardiac Procedures in Patients with a Left Ventricular Assist Device
Authors: Comino-Trinidad Oscar , M. Baltar Iria , Sandoval Elena , Castel María Ángeles , Giménez-Milá Marc
Published: September 2024

Background: The use of durable left ventricular assist devices (LVADs) for advanced heart failure is increasing and a growing number of patients will require anesthesia for non-cardiac procedures (NCPs). The goal of this study was to describe our experience with NCPs for LVAD patients. Methods: All anesthetic procedures performed in LVAD patients at a single center were reviewed from 2014 to 2023. Perioperative management data and complications were assessed. Results: In total, 16 patients had an LVAD implanted and 9 (56.3%) patients underwent anesthesia for a total of 22 NCPs. Most of the procedures took place outside of the operating room, mainly in the endoscopy unit, as gastrointestinal endoscopy was the most common procedure (13, 59.2%). Sedation was provided in 17 procedures (77.3%). Standard monitoring was used in all cases, and invasive monitoring was applied just in cases of major surgeries. There were no intraoperative complications reported. Postoperative complications were recorded after eight (36.4%) of the procedures, consisting mainly of lower gastrointestinal bleeding after lower endoscopy, which increased the length of hospital stay. All procedures were performed by non-cardiac anesthesiologists. Conclusions: Our data suggest that, in most cases, adherence to standard anesthesia practices can be suitable for NCPs in LVAD patients.
Psychotic Arousal and the Psychopathology of Acute Schizophrenia: An Exploratory Study of the Experiential Emotional State in Acute Psychosis
Authors: Margariti Maria M. , Vlachos Ilias I. , Mpourazana Dimitra , Aristotelidis Panagiotis , Selakovic Mirjana , Ifanti Maria , Papageorgiou Charalambos
Published: September 2024

Background: Increasing research data suggest that the dysfunction of emotional brain systems may be an important contributor to the pathophysiology of schizophrenia. However, contemporary psychopathology consistently underestimates the role of emotions in the phenomenology of the disease. Psychotic arousal (PA) is a conceptually defined psychopathological construct aiming to portray the experiential emotional state of acute psychosis. The concept provides an explanatory model for the emergence of psychosis, and the formation and maintenance of delusions based on neurobiological models on the formation of core consciousness and subjectivity. This is the first exploratory study of the major assumptions, endorsed in the project summarized as follows: (1) psychotic arousal is a discrete state, eligible for investigation; (2) abnormal experiential feelings are an integral part of this state; and (3) the state is responsive to antipsychotic intervention during the first weeks of treatment. Methods: We developed the Psychotic Arousal Scale (PAS) accordingly, explored its first psychometric properties and tested its relation to other psychopathological measures. Fifty-five acute schizophrenia patients were evaluated with the PAS, the Positive and Negative Syndrome Scale, the Brown Assessment of Beliefs Scale, the Hamilton Anxiety Scale, and the Calgary Depression Scale. Cronbach α coefficients, t-test analysis, correlations and mixed linear regression models were applied for testing the internal reliability of the scale, associations between parameters and sensitivity to change in three time periods during therapeutic intervention. Results: The results of the study support that (PA) is eligible for investigation as a discrete psychopathological state. Abnormal experiential feelings are an integral part of this state, presenting high affinity with other affective measures; their degree of severity relates to the delusions’ conviction and are amenable to antipsychotics early in treatment during the acute psychotic episode. Conclusions: The findings of this exploratory study are connotative of the presence of an emotional arousal permeated by abnormal experiential feelings during acute psychosis, largely overlooked by contemporary psychopathology.
A Longitudinal Decline in Walking Speed Is Linked with Coexisting Hypertension and Arthritis in Community-Dwelling Older Adults
Authors: Alrawaili Saud M. , Alkhathami Khalid , Elsehrawy Mohammed G. , Alghamdi Mohammed S. , Alkahtani Hussein M. , Alhwoaimel Norah A. , Alenazi Aqeel M.
Published: September 2024

Objective: The aim was to investigate the association between baseline coexistence of hypertension (HTN) and arthritis, HTN alone, or arthritis alone, and their impact on longitudinal physical function measures among community-dwelling older adults over 5 years of follow-up. Methods: Ours was a longitudinal prospective cohort study from the second wave (2010–2011) and third wave (2015–2016) of the National Social Life, Health, and Aging Project (NSHAP). Data for older adults were used. Participants were categorized based on self-reported diagnoses into four groups: coexisting HTN and arthritis, HTN only, arthritis only, or neither. Physical performance measures included walking speed using the 3-Meter Walk Test and the Five Times Sit-to-Stand Test (FTSST). Multiple generalized estimating equations with linear regression analyses were conducted, adjusting for age, sex, race, body mass index (BMI) educational level, pain severity, and baseline use of pain and hypertension medications. Results: Data for 1769 participants were analyzed. Slower walking speed was only associated with coexisting HTN and arthritis (B = −0.43, p < 0.001) after accounting for covariates. The coexisting HTN and arthritis group showed no significant association with FTSST (B = 0.80, p = 0.072) after accounting for covariates. Conclusions: The coexistence of baseline HTN and arthritis in older adults is associated with a gradual decline in only walking speed as a physical performance measure in older adults.
Impact of Newly Diagnosed Left Bundle Branch Block on Long-Term Outcomes in Patients with STEMI
Authors: Anghel Larisa , Stătescu Cristian , Sascău Radu Andy , Tudurachi Bogdan-Sorin , Tudurachi Andreea , Benchea Laura-Cătălina , Prisacariu Cristina , Radu Rodica
Published: September 2024

Background/Objectives: This study assessed the long-term prognostic implications of newly developed left bundle branch block (LBBB) in patients with ST-elevation myocardial infarction (STEMI) and a single coronary lesion, following primary percutaneous coronary intervention (PCI). Methods: Among 3526 patients admitted with acute myocardial infarction between January 2011 and December 2013, 42 were identified with STEMI, a single coronary lesion, and newly diagnosed LBBB. A control group of 42 randomly selected STEMI patients without LBBB was also included. All participants were prospectively evaluated with a median follow-up duration of 9.4 years. Demographic, clinical, and laboratory data were analyzed to assess the impact of LBBB on long-term outcomes. Results: The baseline characteristics were similar between the groups. The STEMI with new LBBB group had significantly higher rates of new myocardial infarction, revascularization, and mortality, highlighting the severe prognostic implications and elevated risk for adverse outcomes compared to STEMI without LBBB. The multivariate Cox regression analysis demonstrated that the presence of LBBB (HR: 2.15, 95% CI: 1.28–3.62, p = 0.003), lower LVEF (HR: 1.45, 95% CI: 1.22–1.72, p < 0.001), and longer pain-to-admission time (HR: 1.32, 95% CI: 1.09–1.61, p = 0.008) were significant independent predictors of adverse outcomes. Conclusions: Newly acquired LBBB in STEMI patients is associated with poorer long-term outcomes. Early identification and management of factors such as reduced LVEF and timely hospital admission, specifically in patients with new-onset LBBB, can improve prognosis.
High-Density Lipoprotein-Associated Paraoxonase-1 (PON-1) and Scavenger Receptor Class B Type 1 (SRB-1) in Coronary Artery Disease: Correlation with Disease Severity
Authors: Kumar Manish , Ali Wahid , Yadav Kusum , Kaumri Swati , Mishra Sridhar , Nardi Paolo , Iellamo Ferdinando , Bernardini Sergio , Pradhan Akshyaya , Perrone Marco Alfonso
Published: September 2024

Background: Coronary artery disease (CAD) is the leading cause of death worldwide. High-Density lipoprotein (HDL) is a well-established marker associated with CAD. The current research goes beyond the conventional HDL-C measurement in previous studies and dives into the functional intricacies of HDL. By understanding how HDL works, rather than just how much of it exists, we can better tailor diagnostic and therapeutic strategies for CAD and related conditions. Hence, the current study quantifies the serum levels of two novel HDL-associated markers, Paraoxonase-1 (PON-1) and Scavenger Receptor Class B Type 1 (SRB-1), in CAD cases vs. controls. Methods: A total of 92 subjects, including 69 CAD and 23 healthy controls, were included, based on the prevalence of the disease. Further, based on the severity of the disease, CAD cases were subcategorized as CAD-I, -II, and -III. Serum PON-1 and SRB-1 levels were measured and compared between patient and control groups. Results: The levels of PON-1 and SRB-1 (32.6 ng/mL and 12.49 ng/mL) were significantly lower in CAD patients vs. the healthy control, at 60.36 ng/mL and 15.85 ng/mL, respectively (p < 0.000). A further intergroup comparison showed a statistically significant difference between the CAT-I and -III for PON-1 (p < 0.025), the CAT-I and -III, and CAT-II and -III for SRB-1 (p < 0.000). The receiver operating characteristics (ROC) curve showed cutoff values of 48.20 ng/mL and 14.90 ng/mL for PON-1 and SRB-1. Conclusions: The current study found that serum levels of HDL-associated PON-1 and SRB-1 are significantly lower in CAD cases, and were also inversely related to the increasing severity of coronary artery disease. This inference implies that serum PON-1 and SRB-1 could be used as non-invasive tools for the identification of coronary atherosclerosis and risk assessment in CAD cases.
Polypills in the Management of Cardiovascular Risk—A Perspective
Authors: de Abreu-Silva Erlon Oliveira , Siepmann Martin , Siepmann Timo
Published: September 2024

Cardiovascular disease and cardiovascular risk factors are global healthcare problems, given their high prevalence and the recognized low rates of adequate control despite the abundant body of evidence on different therapeutic options. The World Heart Federation has scrutinized the reasons for poor control of cardiovascular risk factors. Among these reasons, patients’ poor adherence to treatment regimens as well as limited rates of evidence-based therapy prescription from healthcare providers play a substantial role in the challenge of cardiovascular risk management. Polypills are fixed-dose combinations including two or more active drugs, from different pharmacological classes, combined in a single dosage form. Polypills were designed to simplify the clinical management of pharmacotherapy and increase adherence to treatment. From this perspective, we discuss the current literature on the use of polypills in the primary and secondary prevention of cardiovascular disease as well as future challenges and the potentials of this treatment strategy.
Dynamic Progression of Hypertension and Diabetes in the Democratic Republic of Congo from 2019 to 2023
Authors: Angendu Karl B. , Akilimali Pierre Z. , Tran Nguyen Toan , Magne Julien
Published: September 2024

Introduction: The Democratic Republic of Congo (DRC) does not have national prevalence data for arterial hypertension (HTN) or diabetes (type I and II combined) to aid evidence-based decision-making, despite the assumption of epidemiological transition in low- and middle-income countries. The aim of this study was to estimate a proxy of prevalence for HTN and diabetes. Methodology: This study used routine monthly reported data pertaining to HTN and diabetes from the District Health Information Software 2 (DHIS2), spanning 2019–2023. Data underwent quality assessment and adjustments using standardization before analysis. Equity analyses were carried out at the national and sub-national levels. Epidemiological curves and maps were produced to analyze trends in the prevalence of HTN and diabetes among adults aged 18 and over. Permission to use the data was obtained from the regulatory authority. Results: Over five years, incidence of HTN increased from 13.23% (CI 95%: 13.22–13.24) to 15.23% (CI 95%: 15.22–15.24) (+15.1% relative increase), and diabetes rose from 2.73% (CI 95%: 2.72–2.74) to 3.345% (CI 95%: 3.34–3.35) (+16.3% relative increase), with provincial variations observed. Conclusions: In the DRC, hypertension and diabetes are advancing rapidly. Primary and preventative healthcare services and public health interventions must prioritize these diseases.
Functional Biomaterials and Biomaterial Composites with Antimicrobial Properties
Authors: Luong John H. T.
Published: September 2024

AMR occurs when bacteria, viruses, fungi, and parasites no longer respond to antimicrobial medicines, including antibiotics, antivirals, antifungals, and antiparasitics [...]
Stress Distribution of Pediatric Zirconia and Stainless Steel Crowns after Pulpotomy Procedure under Vertical Loading: A Patient-Specific Finite Element Analysis
Authors: Doğan Özgür
Published: September 2024

Aim: With modern dentistry advancements, children and parents have significantly raised aesthetic expectations in pediatric dentistry. Pediatric zirconia crowns (PZCs) provide a superior aesthetic appearance compared with stainless steel crowns (SSCs), making them a popular treatment option. However, a comparison of the compressive stresses caused by these crowns on the roots of primary teeth and alveolar bones has not been conducted. Materials and Methods: Cone beam computed tomography (CBCT) images of an eight-year-old female patient who experienced premature loss of a primary mandibular left second molar were obtained from a dental hospital database. Rhinoceros 4.0 software was used to process and simulate images. Under simulated chewing forces, stress on the PZC, SSC, and intact primary first molars as control groups, as well as their roots and alveolar bone structures, was assessed with finite element analysis. Statistical Analyses: Depending on whether the descriptive data were normally distributed, the Student t-test and Mann–Whitney U test were used. Quantitative variables differ between the two categories of qualitative variables. One-way ANOVA and Kruskal–Wallis H tests were used depending on standard distribution assumptions. p < 0.05 indicates statistical significance differences. Results: PZCs, SSCs, and cement layers were stressed according to von Mises values, while roots and alveolar bones were stressed according to maximum and minimum stress values. When assessing crowns, SSCs exhibited the highest von Mises stress values, followed by PZCs and control groups (p < 0.001). In the cement layer, SSCs obtained significantly higher values (p = 0.003). In the root area, minimum principal stress values are more critical. The highest values were obtained from the intact tooth, PZC, and SSC, respectively (p < 0.001). Alveolar bones did not differ significantly in minimum principal stress (p = 0.950). Conclusions: Restorative full-coverage crowns exhibited higher von Mises values than intact teeth, as per current research findings. The von Mises values were highest in SSC, while lowest in PZC. As a result of this condition, the cement layer and root areas had higher von Mises stress and compressive stress. Alveolar bones were not affected regardless of restoration type. PZC transmits higher stress due to its properties.
Leveraging Perspective Transformation for Enhanced Pothole Detection in Autonomous Vehicles
Authors: Abu-raddaha Abdalmalek , El-Shair Zaid A. , Rawashdeh Samir
Published: September 2024

Road conditions, often degraded by insufficient maintenance or adverse weather, significantly contribute to accidents, exacerbated by the limited human reaction time to sudden hazards like potholes. Early detection of distant potholes is crucial for timely corrective actions, such as reducing speed or avoiding obstacles, to mitigate vehicle damage and accidents. This paper introduces a novel approach that utilizes perspective transformation to enhance pothole detection at different distances, focusing particularly on distant potholes. Perspective transformation improves the visibility and clarity of potholes by virtually bringing them closer and enlarging their features, which is particularly beneficial given the fixed-size input requirement of object detection networks, typically significantly smaller than the raw image resolutions captured by cameras. Our method automatically identifies the region of interest (ROI)—the road area—and calculates the corner points to generate a perspective transformation matrix. This matrix is applied to all images and corresponding bounding box labels, enhancing the representation of potholes in the dataset. This approach significantly boosts detection performance when used with YOLOv5-small, achieving a 43% improvement in the average precision (AP) metric at intersection-over-union thresholds of 0.5 to 0.95 for single class evaluation, and notable improvements of 34%, 63%, and 194% for near, medium, and far potholes, respectively, after categorizing them based on their distance. To the best of our knowledge, this work is the first to employ perspective transformation specifically for enhancing the detection of distant potholes.
Artificial Neural Network-Based Route Optimization of a Wind-Assisted Ship
Authors: Guzelbulut Cem , Badalotti Timoteo , Fujita Yasuaki , Sugimoto Tomohiro , Suzuki Katsuyuki
Published: September 2024

The International Maritime Organization aims for net-zero carbon emissions in the maritime industry by 2050. Among various alternatives, route optimization holds an important place as it does not require any additional component-related costs. Especially for wind-assisted ships, the effectiveness of different sailing systems can be improved significantly through route optimization. However, finding the ship’s optimal route is computationally expensive when the totality of possible weather conditions is taken into consideration. To determine the optimal route that minimizes energy consumption, an energy model based on the environmental conditions, ship route and ship speed was built using artificial neural networks. The energy consumed for given input data was calculated using a ship dynamics model and a database was generated to train the artificial neural networks, which predict how much energy is consumed depending on the route followed in given environmental conditions. Then, such networks were exploited to derive the optimal routes for all the relevant operational conditions. It was found that route optimization can reduce the overall ship energy consumption depending on the weather conditions of the environment by up to 9.7% without any increase in voyage time and by up to 35% with a 10% delay in voyage time. The proposed methodology can be applied to any ship by training real weather conditions and provides a framework for reducing energy consumption and greenhouse gas emissions during the service life of ships.
Vibration Safety Threshold and Control Technology for Blasting to Prevent Seawater Intrusion in Coastal Tunnel Sections Near Faults
Authors: Wu Xiaodong , Miao Xiaomeng , Gong Min , Su Junpeng , Zhu Yaqi , Chen Xiaolei
Published: September 2024

Coastal underground engineering projects are prone to seawater intrusion during blasting operations, posing significant risks to the safety of construction personnel and the structural integrity of the projects. To ensure the safety of blasting operations in areas at risk of seawater intrusion, this study focuses on a section of a coastal tunnel that is at risk of such intrusion. Using fracture mechanics theory and silo theory analysis methods, the minimum safe distance between the workface and the fault to prevent seawater intrusion is determined. Numerical simulations are employed to analyze the dynamic response of the surrounding rock and the attenuation of vibrations as blasting excavation progresses near the fault-controlled zone. This study also explores the impact of dynamic excavation on fault stability. By employing a regression analysis, this study establishes quantitative relationships between the amount of explosive used and the peak particle velocity (PPV) at different distances, as well as between the range of rock damage and PPV at various distances. This analysis allows for the determination of a safe PPV threshold to prevent seawater intrusion in the fault-controlled area. The accuracy of the computational model is validated using field-measured data. Finally, an optimized blasting design and strategy based on electronic detonator initiation are proposed for the control area, ensuring construction safety. This study provides theoretical and technical references for achieving safe and efficient blasting excavation in coastal underground engineering projects.
Study on the Dynamic Response of Mooring System of Multiple Fish Cages under the Combined Effects of Waves and Currents
Authors: Liu Fuxiang , Jiang Zhentao , Cheng Tianhu , Xu Yuwang , Zhu Haitao , Wang Gang , Sun Guoqing , Zhang Yuqin
Published: September 2024

Deep-sea aquaculture can alleviate the spatial and environmental pressure of near-shore aquaculture and produce higher quality aquatic products, which is the main development direction of global aquaculture. The coastline of China is relatively flat, with aquaculture operations typically operating in sea areas with water depths of approximately 30–50 m. However, with frequent typhoons and poor sea conditions, the design of mooring system has always been a difficult problem. This paper investigated the multiple cages, considering two layouts of 1 × 4 and 2 × 2, and proposed three different mooring system design schemes. The mooring line tension of the mooring systems under the self-storage condition was compared, and it was observed whether the mooring line accumulation and the contact between the mooring line and the steel structure occurred on the leeward side. Additionally, flexible net models were compared with rigid net models to evaluate the impact of net deformation on cage movement and mooring line tension. Finally, based on the optimal mooring design, the dynamic response of the mooring system under irregular wave conditions was analyzed and studied, providing important reference for the safety and economic design of the mooring system of multiple fish cages.
The Quasistatic Pressure Characteristics of a Confined Cabin in a Water Mist Environment
Authors: Zhang Ya , Li Xiaobin , Xi Xiuyi , Li Mengzhen , Zhang Yiheng , Huang Hai , Chen Wei
Published: September 2024

To investigate the quasistatic pressure load characteristics of an explosion in a confined cabin in a water mist environment, explosion tests were conducted under different explosive and water mist masses. The concentration of water mist, droplet diameter, and quasistatic pressure inside the cabin were measured. On the basis of the theoretical model of quasistatic pressure in adiabatic ideal gas cabins, a theoretical model of the quasistatic pressure in a confined cabin in a water mist environment was established. On the basis of experimental data and theoretical models, an empirical formula was proposed for the peak quasistatic pressure of implosion in a water mist environment. A model for a cabin explosion in a water mist environment was established, and the load characteristics of a cabin explosion under high water mist concentrations were analyzed. The relevant research results contribute to the prediction of the quasistatic pressure of explosions in a confined cabin in a water mist environment.
Influence of Bed Variations on Linear Wave Propagation beyond the Mild Slope Condition
Authors: Simarro Gonzalo
Published: September 2024

As water waves travel from deep to shallow waters, they experience increased nonlinearity and decreased dispersion due to the reduced water depth. While the impact of bed slope on wave propagation celerity is documented, it is often overlooked in commonly used depth-integrated wave models. This study uses the WKB approximation and solves higher-order slope-related terms to analyze the influence of varying depth, including the gradient and laplacian of water depth. One result is an extended longwave for linear wave reflection and transmission on a ramp to deeper waters. The main outcome and focus of this work, however, is a new, simple analytical expression for linear dispersion that includes bed variations. The results are applied to two cases: wind-generated water wave propagation in the nearshore, emphasizing corrections to bathymetry inversion methods, and tsunami propagation over the continental slope, highlighting the limitations of neglecting slope on dispersion and the significant role of the Laplacian of water depth.
Pressure Fluctuation Characteristics of a Pump-Turbine in the Hump Area under Different Flow Conditions
Authors: Zheng Kai , Chen Liu , Ren Shaocheng , Xiao Wei , Xiao Yexiang , Rai Anant Kumar , Shi Guangtai , Hao Zhengkai
Published: September 2024

During the operation of a reversible pump-turbine, a hump area can easily appear under the pump condition, which will greatly affect the performance of a storage unit, with pressure pulsation being the key factor for the stable operation of a pump-turbine. Therefore, in order to explore the pressure pulsation characteristics of each flow component in the hump area, this paper first compared the full characteristics of the model test under different working conditions, and then it analyzed the pressure pulsation characteristics. By analyzing the pressure pulsation characteristics in the unit’s flow component under different flow rates in the hump area, the pulsation rule of a pump-turbine running in the hump area was revealed. It was found that the peak-to-peak value of the draft tube in the hump area was the smallest under the optimal flow condition, and the peak-to-peak value increased along the flow direction, with the rotor and stator interaction (RSI) effects being continuously enhanced. When away from the runner basin, the influence of RSI gradually weakened after leaving the runner. No low frequency was found in the optimal traffic. The peak-to-peak value of the low flow condition increased compared with the optimal flow condition, and the distribution was not uniform. The main frequency of the whole basin was relatively complex, indicating that the flow of water was unstable in the condition of partial load, resulting in the hump area during the unit operation. The research results can provide a theoretical reference for improving the stability of pump-turbines.
Secure Dynamic Scheduling for Federated Learning in Underwater Wireless IoT Networks
Authors: Yan Lei , Wang Lei , Li Guanjun , Shao Jingwei , Xia Zhixin
Published: September 2024

Federated learning (FL) is a distributed machine learning approach that can enable Internet of Things (IoT) edge devices to collaboratively learn a machine learning model without explicitly sharing local data in order to achieve data clustering, prediction, and classification in networks. In previous works, some online multi-armed bandit (MAB)-based FL frameworks were proposed to enable dynamic client scheduling for improving the efficiency of FL in underwater wireless IoT networks. However, the security of online dynamic scheduling, which is especially essential for underwater wireless IoT, is increasingly being questioned. In this work, we study secure dynamic scheduling for FL frameworks that can protect against malicious clients in underwater FL-assisted wireless IoT networks. Specifically, in order to jointly optimize the communication efficiency and security of FL, we employ MAB-based methods and propose upper-confidence-bound-based smart contracts (UCB-SCs) and upper-confidence-bound-based smart contracts with a security prediction model (UCB-SCPs) to address the optimal scheduling scheme over time-varying underwater channels. Then, we give the upper bounds of the expected performance regret of the UCB-SC policy and the UCB-SCP policy; these upper bounds imply that the regret of the two proposed policies grows logarithmically over communication rounds under certain conditions. Our experiment shows that the proposed UCB-SC and UCB-SCP approaches significantly improve the efficiency and security of FL frameworks in underwater wireless IoT networks.
The Impact of Container Ship Trim on Fuel Consumption and Navigation Safety
Authors: Musulin Mario , Mihanović Luka , Balić Katarina , Musulin Hrvoje Nenad
Published: September 2024

Fuel consumption, fuel cost savings, environmental pollution, and navigation safety are significant factors for shipping companies. Maritime transport represents 3% of total greenhouse gas emissions globally. Trim optimization is one of the ways to save energy and reduce ship emissions. Thus, this study aimed to evaluate how the optimization of the trim of container ships at different speeds can decrease exhaust gas emissions and fuel consumption while considering the safety of navigation. This research was conducted by calculating the fuel consumption in real conditions and calculating the optimal trim for different speeds and gases of a container ship of 11,400 TEU. All obtained results were statistically processed to analyze fuel consumption at various speeds, considering the ship’s trim. It turns out that savings should never be at the expense of navigation safety, especially in limited maneuvering areas, such as canals. When maneuvering in such places it is necessary to adjust the trim to ensure navigation safety, i.e., to improve the rudder and propulsion device response, instead of reducing fuel consumption
Updated Review of Longshore Sediment Transport: Advantages, Disadvantages, and Comparisons Using a Satellite Image Methodology
Authors: Alpaca-Chacón César M. , Jigena-Antelo Bismarck , Quispe-Gonzales César A. , Sarango-Julca Douglas D. , Contreras-de-Villar Antonio , Muñoz-Perez Juan J.
Published: September 2024

This review updates the different categories and formulations of the calculation of longshore sediment transport (LST) and summarizes their advantages and disadvantages. Most of these methodologies require calibration for areas different from those studied by their authors. Thus, a method of validation and calibration is presented here by processing satellite images with CoastSat software (release v 2.7) to determine accretion and erosion volumes. This low-cost methodology was applied to Salaverry Beach (Peru) to compare the results of the different formulations. A range of variation between −96% and +68% was observed concerning the error, with van Rijn’s formula being the most accurate for this particular case.
Research on LSTM-Based Maneuvering Motion Prediction for USVs
Authors: Guo Rong , Mao Yunsheng , Xiang Zuquan , Hao Le , Wu Dingkun , Song Lifei
Published: September 2024

Maneuvering motion prediction is central to the control and operation of ships, and the application of machine learning algorithms in this field is increasingly prevalent. However, challenges such as extensive training time, complex parameter tuning processes, and heavy reliance on mathematical models pose substantial obstacles to their application. To address these challenges, this paper proposes an LSTM-based modeling algorithm. First, a maneuvering motion model based on a real USV model was constructed, and typical operating conditions were simulated to obtain data. The Ornstein–Uhlenbeck process and the Hidden Markov Model were applied to the simulation data to generate noise and random data loss, respectively, thereby constructing a sample set that reflects real experiment characteristics. The sample data were then pre-processed for training, employing the MaxAbsScaler strategy for data normalization, Kalman filtering and RRF for data smoothing and noise reduction, and Lagrange interpolation for data resampling to enhance the robustness of the training data. Subsequently, based on the USV maneuvering motion model, an LSTM-based black-box motion prediction model was established. An in-depth comparative analysis and discussion of the model’s network structure and parameters were conducted, followed by the training of the ship maneuvering motion model using the optimized LSTM model. Generalization tests were then performed on a generalization set under Zigzag and turning conditions to validate the accuracy and generalization performance of the prediction model.
Application of Self-Polishing Copolymer and Tin-Free Nanotechnology Paint for Ships
Authors: Wang Yushi , Hsu Cheunghwa , Pan Guanhong , Chen Chenghao
Published: September 2024

During a ship’s voyage, it is difficult to maintain its hull, and prolonged exposure to seawater can lead to the attachment of marine organisms, which can negatively impact the ship’s speed. The original self-polishing copolymer was a tributyltin-containing paint used for applying two layers of protective coating onto a ship’s bottom plate. According to International Maritime Organization (abbreviated as IMO) regulations, users are no longer allowed to use paints containing tributyltin. Therefore, manufacturers have developed a tributyltin-free paint, known as tin-free nanotechnology paint, which can be used as a replacement for the base coat on ship bottom plates. This study involves the use of a self-polishing copolymer spray and tin-free nanotechnology paint. A model coated with these two types of paint will be observed underwater to study the growth of marine organisms. Additionally, fuel consumption will be analyzed through underwater inspections and sea trials. Based on the experimental data, it is known that tin-free nanotechnology paint can significantly reduce the need for repairs in factories and greatly decrease maintenance costs when compared to self-polishing copolymers.