bluuebunny/crossref_metadata_2025 huggingface dataset:
Burden of Mental Health among Patients with Inflammatory Bowel Disease—A Cross-Sectional Study from a Tertiary IBD Center in Hungary
Authors: Lontai Livia , Elek Lívia Priyanka , Balogh Fruzsina , Angyal Dorottya , Pajkossy Péter , Gonczi Lorant , Lakatos Peter L. , Iliás Ákos
Published: March 2024

Background: Inflammatory bowel diseases (IBDs) are chronic conditions that negatively affect the patient’s quality of life. With the spread of the biopsychosocial model, the role of mental health in the activity and course of inflammatory bowel disease is becoming more and more recognized. Our study aimed to assess the prevalence of anxiety and depression in IBD patients in our tertiary referral center and determine the predictive factors of these mental conditions. Methods: A total of 117 patients were included consecutively between 1 December 2021 and 28 February 2022. We used a questionnaire to gather demographic information, disease course, and IBD-specific symptoms. We assessed anxiety symptoms using the GAD-7 and depressive complaints using the PHQ-9 questionnaire. We evaluated disease activity using CDAI and pMayo scores. Results: Of the 117 patients (male/female: 63/54), 88 suffered from Crohn’s disease, and 29 were diagnosed with ulcerative colitis. Only 6 patients were taking medication for mood disorders, and 38 individuals sought mental support during their lifetime. A total of 15% of the population suffered from moderate–severe anxiety disorder, and 22% were affected by moderate–severe depression. The GAD-7 and PHQ9 values showed a significant correlation between the number of stools, bloody stools, abdominal pain, number of flare-ups, and CDAI scores. Conclusions: Our study confirmed that there is a high incidence of anxiety and depressive symptoms among IBD patients. Our results highlighted the symptoms that could be associated with mental disorders. It is important to assess the mental status of IBD patients to improve their quality of life.
Visuospatial Function in Women with Premenstrual Dysphoric Disorder
Authors: Hamidovic Ajna , Cho Soojeong , Smadi Shahd , Davis John
Published: March 2024

Background/Objectives: Premenstrual dysphoric disorder (PMDD) is an understudied psychiatric condition affecting reproductive-age women who experience negative mood in the luteal phase of the menstrual cycle. Cognitive functions in PMDD are not well understood as patients have been tested in the luteal phase. This may confound study results due to noted emotional interferences, as well as the potential opposing effects of the sex hormones estradiol and progesterone. In the present study, we evaluated visuospatial function in the follicular phase in women with PMDD and healthy controls, and further examined the effect of estradiol as research into the hormonal mediation of visuospatial function in reproductive-age women has produced mixed results. Methods: To this end, we analyzed estradiol concentrations using the gold standard mass spectrometry. Serum samples were collected in the early follicular and mid/late follicular subphases when estradiol is low and high, respectively, while progesterone is low and steady. We assessed visuospatial function using the classic mental rotation task. Results: Women with PMDD had a higher mental rotation total score (t = 2.17; p < 0.05). The addition of six demographic, biological, and anthropomorphic variables in a hierarchical fashion accounted for 45.3% of the total variance in the final model with diagnosis remaining statistically significant (t = 4.36; p < 0.001). Estradiol did not mediate the group difference and was not significantly associated with visuospatial function. Conclusions: The present results provide support for new research directions into the potential biological mechanisms that underlie the pathophysiology of PMDD, represented as enhanced visuospatial ability in women with PMDD in the follicular phase. We review the theory that PMDD is a disorder of the enhanced excitation-to-inhibition ratio, with a focus on findings to date from brain imaging research.
A Novel Therapeutic Approach of 980 nm Photobiomodulation Delivered with Flattop Beam Profile in Management of Recurrent Aphthous Stomatitis in Paediatrics and Adolescents—A Case Series with 3-Month Follow-Up
Authors: Hanna Reem , Miron Ioana Cristina , Benedicenti Stefano
Published: March 2024

Background/Objectives: Recurrent aphthous stomatitis (RAS) is one of the most common oral mucosal lesions and a very debilitating lesion, especially in paediatric and adolescent patients. The current pharmacotherapy offers a pain relief but not without side effects, and therefore photobiomodulation (PBM) can be an alternative therapy. To the authors’ best knowledge, no published study has explored the efficacy of λ 980 nm laser PBM in the management of all RAS subtypes in paediatric and adolescent patients, and therefore, this prospective observational clinical study was conducted to bridge this gap by evaluating λ 980 nm laser PBM efficacy in symptomatic RAS management in paediatric and adolescent patients. The objectives were to evaluate (1) pain intensity alleviation; (2) wound healing rate; (3) wound size closure; (4) a complete resolution; (5) evidence of recurrence; and (6) patients’ treatment satisfaction. Methods: The study’s variables were assessed at the following timepoints: T0: pre-treatment; T1: immediately after first PBM session; T2: 5 hours (h) post first PBM session (via telephone call); T3: immediately after second PBM session (three days post first PBM session); T4: three-day follow-up (after complete PBM treatments); T5: two-week follow-up; and T6: three-month follow-up. The following PBM dosimetry and treatment protocols were employed: λ 980 nm; 300 mW; 60 s; 18 J; CW; flattop beam profile of 1 cm2 spot size; 18 J/cm2; and twice-a-week irradiation (72 h interval). Results: At T1, significant immediate pain intensity relief was reported. 33.33% recorded “4” and 66.67% reported “5” on the quantitative numeric pain intensity scale (NPIS), and this continued to improve significantly (83.33%) at T2. All the subjects reported “0” on the NPIS at T3, T4, T5 and T6. There was a significant reduction in the lesion surface area (>50% complete healing) at T3 compared to T0. Complete healing (100%) with no evidence of scarring and lesion recurrence observed at T4, T5 and T6. Very good patients’ satisfaction was reported at all timepoints. Conclusions: This is the first report demonstrating λ980 nm efficacy in all RAS subtype management in paediatric and adolescent patients with a 3-month follow-up, whereby its PBM dosimetry and treatment protocols were effective from scientific and practical standpoints, and hence multicentre RCTs with large data are warranted to validate its reproducibility and to enrich the knowledge of PBM application in all RAS subtypes.
Inappropriate Underdosing of Direct Oral Anticoagulants in Atrial Fibrillation Patients: Results from the START2-AF Registry
Authors: Poli Daniela , Antonucci Emilia , Ageno Walter , Berteotti Martina , Falanga Anna , Pengo Vittorio , Chiarugi Paolo , Cosmi Benilde , Paparo Carmelo , Chistolini Antonio , Insana Antonio , Lione Domenico , Malcangi Giuseppe , Martini Giuliana , Masciocco Lucilla , Pedrini Simona , Bucherini Eugenio , Pastori Daniele , Pignatelli Pasquale , Toma Andrea , Testa Sophie , Palareti Gualtiero ,   START AF Study Group
Published: March 2024

Background: Direct oral anticoagulants (DOACs) are recommended for stroke prevention in non-valvular atrial fibrillation (NVAF) patients. We aimed to describe the prevalence of inappropriate DOACs dose prescription in the START2-AF Registry, the outcomes according to the appropriateness of the dosage, and the factors associated with inappropriate dose prescription. Methods: Patients’ demographics and clinical data were prospectively collected as electronic files in an anonymous form on the website of the START2-Registry; DOACs dosage was determined to be appropriate when prescribed according to the European Heart Rhythm Association Guidelines. Results: We included 5943 NVAF patients on DOACs; 2572 (46.3%) were female patients. The standard dose (SD) was prescribed to 56.9% of patients and the low dose (LD) was prescribed to 43.1% of patients; 38.9% of all NVAF patients received an inappropriate LD DOAC and 0.3% received inappropriate SD. Patients treated with LD DOAC had a significantly higher rate of all bleedings (RR 1.5; 95% CI 1.2–2.0), major bleedings (RR 1.8; 95% CI 1.3–1.7), and mortality (RR 2.8; 95% CI 1.9–4.1) with respect to patients treated with SD DOAC. No difference was found among patients treated with appropriate and inappropriate LD regarding bleeding, thrombotic, and mortality rates. Age, body weight <60 kg, and renal failure were significantly associated with inappropriate LD DOAC prescription. Conclusions: Inappropriate LD DOACs in NVAF patients is not associated with a reduction in bleeding risk, nor with an increased thrombotic risk. Instead, it is associated with higher mortality rate, suggesting that, in clinical practice, underdosing is preferred for patients at particularly high risk for adverse events.
Maxillofacial Microvascular Free-Flap Reconstructions in Pediatric and Young Adult Patients—Outcomes and Potential Factors Influencing Success Rate
Authors: Lech Dominika , Matysek Jeremi , Maksymowicz Robert , Strączek Cyprian , Marguła Robert , Krakowczyk Łukasz , Kozakiewicz Marcin , Dowgierd Krzysztof
Published: March 2024

Background: Maxillofacial microvascular free-flap reconstructions are significant interventions in the management of congenital defects, traumatic injuries, malignancies, and iatrogenic complications in pediatric and young adult patients. Craniofacial disorders within this demographic can result in profound functional, cosmetic, and psychosocial impairments, highlighting the critical need for thorough investigation into factors that may influence procedural success and postoperative quality of life. This retrospective chart review aims to examine the outcomes and potential influencing factors, aiming to offer valuable insights into optimizing the effectiveness of these reconstructions and improving patient outcomes. Methods: A single head and neck surgical team performed all the included 136 procedures. Demographic and surgical patient data were recorded. Type of transfer performed in each recipient site and major complications were analyzed. Relevant influencing factors, such as age, gender, and etiology of defect were determined using the ANOVA test and χ2 test of independence. Results: The results indicate a 90% success rate. No significant relationship was found between the incidence of total flap loss and patient age, etiology, or graft source. The maxillary reconstructions showed a higher incidence of total flap loss compared to mandibular reconstructions (11 vs. 3 cases). Conclusions: Despite the high success rate, the findings underline the necessity for further research to validate these observations and enhance surgical methods for pediatric and young adult patients.
Extracorporeal Shockwave Treatment as Additional Therapy in Patients with Post-Stroke Spasticity of Upper Limb—A Narrative Review
Authors: Starosta Michał , Marek Klaudia , Redlicka Justyna , Miller Elżbieta
Published: March 2024

Stroke is a severe injury of the central nervous system (CNS) and one of the leading causes of long-term disability and mortality. One of the main symptoms of neurological diseases is spasticity. This is defined as a motor condition characterized by a velocity-dependent increase in tonic stretch reflexes with exaggerated tendon jerks and resulting in the hyperexcitability of the stretch reflex. Rehabilitation after a stroke is focused on relearning lost skills and regaining independence. Many new methods in neurorehabilitation have been introduced. This review concentrates on the current evidence for extracorporeal shockwave therapy (ESWT) as a noninvasive alternative to treat spasticity. We present the effect of EWST and radial EWST interventions to post-stroke patients with spasticity in the upper limb. Our collected data suggest that different parameters of shockwaves can be used to achieve functional improvementsin the upper limb after a stroke. Our accumulated data imply that ESWT is safe and can be used for pain relief, reduced muscle tension, and an increased range of motion. According to many studies, complications after shockwave treatment are infrequent. Transient complications after shockwave therapy (ESWT) include redness, tingling, pain, and bruising. We reviewed clinical trials that present the possible benefits in upper-limb function after shockwave therapy for post-stroke patients. In this article, we used many database search engines, including PEDro. In the stroke rehabilitation literature, a key methodological problem is the design of double-blind studies, which very often are not feasible.
Predicting One-Year Mortality after Discharge Using Acute Heart Failure Score (AHFS)
Authors: Magaldi Mariarosaria , Nogue Erika , Molinari Nicolas , De Luca Nicola , Dupuy Anne-Marie , Leclercq Florence , Pasquie Jean-Luc , Roubille Camille , Mercier Grégoire , Cristol Jean-Paul , Roubille François
Published: March 2024

Background: Acute heart failure (AHF) represents a leading cause of unscheduled hospital stays, frequent rehospitalisations, and mortality worldwide. The aim of our study was to develop a bedside prognostic tool, a multivariable predictive risk score, that is useful in daily practice, thus providing an early prognostic evaluation at admission and an accurate risk stratification after discharge in patients with AHF. Methods: This study is a subanalysis of the STADE HF study, which is a single-centre, prospective, randomised controlled trial enrolling 123 patients admitted to hospital for AHF. Here, 117 patients were included in the analysis, due to data exhaustivity. Regression analysis was performed to determine predictive variables for one-year mortality and/or rehospitalisation after discharge. Results: During the first year after discharge, 23 patients died. After modellisation, the variables considered to be of prognostic relevance in terms of mortality were (1) non-ischaemic aetiology of HF, (2) elevated creatinine levels at admission, (3) moderate/severe mitral regurgitation, and (4) prior HF hospitalisation. We designed a linear model based on these four independent predictive variables, and it showed a good ability to score and predict patient mortality with an AUC of 0.84 (95%CI: 0.76–0.92), thus denoting a high discriminative ability. A risk score equation was developed. During the first year after discharge, we observed as well that 41 patients died or were rehospitalised; hence, while searching for a model that could predict worsening health conditions (i.e., death and/or rehospitalisation), only two predictive variables were identified: non-ischaemic HF aetiology and previous HF hospitalisation (also included in the one-year mortality model). This second modellisation showed a more discrete discriminative ability with an AUC of 0.67 (95% C.I. 0.59–0.77). Conclusions: The proposed risk score and model, based on readily available predictive variables, are promising and useful tools to assess, respectively, the one-year mortality risk and the one-year mortality and/or rehospitalisations in patients hospitalised for AHF and to assist clinicians in the management of patients with HF aiming at improving their prognosis.
Traditional Clinicopathological Biomarkers Still Determine Disease-Free and Overall Survival in Invasive Breast Cancer Patients: A Pilot Study
Authors: Wrzeszcz Katarzyna , Kwiatkowska Katarzyna , Rhone Piotr , Formanowicz Dorota , Kruszewski Stefan , Ruszkowska-Ciastek Barbara
Published: March 2024

Background: Molecular classification, tumor diameter, Ki67 expression, and brachytherapy administration still act as the most potent potential predictors of breast cancer recurrence and overall survival. Methods: Over the period of 23 months, we included in the study 92 invasive breast cancer (IBrC) patients initially diagnosed at the Clinical Ward of Breast Cancer and Reconstructive Surgery, Oncology Center in Bydgoszcz, Poland. The probability of disease-free survival (DFS) and overall survival (OS) in relation to potential prognostic factors for the patients were determined using a Kaplan–Meier analysis, and univariate and multivariate Cox regression analyses evaluated the predictive factors of IBrC patients. The investigation of the potential prognostic model’s accuracy was analyzed using the ROC curve. Results: Patients with tumor size < 2 cm, Ki67 expression < 20%, luminal-A molecular subtype, and extra-dose brachytherapy boost administration displayed the most favorable prognosis according to breast cancer disease-free survival and overall survival. The estimated 5 year probability of DFS and OS rates in women with tumor diameter < 2 cm were 89% and 90%, respectively. In tumor diameter > 2 cm, the estimated 5 year probability of DFS was 73% and OS was 76%. Interestingly, the tumor diameter of 1.6 cm with a specificity of 60.5% and a sensitivity of 75% occurred as the best threshold point to differentiate patients with cancer recurrence from those without cancer progression. Conclusions: Our study provides essential information on the clinicopathological profile and future outcomes of early stage IBrC patients. Furthermore, the tumor diameter cut-off value of 1.6 cm discriminating between disease recurrence and those without disease progression patients represents an innovative direction for further research.
The Value of Computed Tomography-Based Planning in Shoulder Arthroplasty Compared to Intra-/Interobserver Reliability of X-ray Planning
Authors: Bischofreiter Martin , Sacan Edanur , Gattringer Michael , Gruber Michael S. , Breulmann Franziska L. , Kindermann Harald , Heuberer Philipp , Mattiassich Georg , Ortmaier Reinhold
Published: March 2024

Background: Reversed total shoulder arthroplasty (RTSA) is an established surgery for many pathologies of the shoulder and the demand continues to rise with an aging population. Preoperative planning is mandatory to support the surgeon’s understanding of the patient’s individual anatomy and, therefore, is crucial for the patient’s outcome. Methods: In this observational study, we identified 30 patients who underwent RTSA with two- and three-dimensional preoperative planning. Each patient underwent new two-dimensional planning from a medical student and an orthopedic resident as well as through a mid-volume and high-volume shoulder surgeon, which was repeated after a minimum of 4 weeks. The intra- and interobserver reliability was then analyzed and compared to the 3D planning and the implanted prosthesis. The evaluated parameters were the size of the pegged glenoid baseplate, glenosphere, and humeral short stem. Results: The inter-rater reliability showed higher deviations in all four raters compared to the 3D planning of the base plate, glenosphere, and shaft. The intra-rater reliability showed a better correlation in more experienced raters, especially in the planning of the shaft. Conclusions: Our study shows that 3D planning is more accurate than traditional planning on plain X-rays, despite experienced shoulder surgeons showing better results in 2D planning than inexperienced ones.
Improvement in Pain, Quality of Life, and Urinary Dysfunction following Correction of Lumbar Lordosis and Reduction in Lumbar Spondylolistheses Using Chiropractic BioPhysics® Structural Spinal Rehabilitation: A Case Series with >1-Year Long-Term Follow-Up Exams
Authors: Fedorchuk Curtis A. , Fedorchuk Cole G. , Lightstone Douglas F.
Published: March 2024

(1) Background: Lumbar spondylolisthesis affects ~20% of the US population and causes spine-related pain and disability. (2) Methods: This series reports on three patients (two females and one male) aged 68–71 years showing improvements in back pain, quality of life (QOL), and urinary dysfunction following correction of lumbar spondylolistheses using CBP® spinal rehabilitation. Pre-treatment radiographs showed lumbar hyperlordosis (−49.6°, ideal is −40°) and anterolisthesis (14.5 mm, ideal is 0 mm). Pre-treatment patient-reported outcome measures (PROMs) included a numeric rating scale (NRS) for back pain (7.3/10, ideal is 0), urinary urgency (8/10, ideal is 0), and SF-36 physical (PCS) and mental component score (MCS) (29.8 and 46.6, ideal is 46.8 and 52.8). Patients underwent 2–3 CBP® sessions per week to correct lumbar hyperlordosis and lumbar anterolistheses. (3) Results: Post-treatment radiographs showed improvements in lumbar curvature (−42.8°) and anterolisthesis (4.2 mm). Post-treatment PROMs showed improvements in NRS for back pain (1/10), urinary urgency (2.3/10), and SF-36 PCS and MCS (50.2 and 57.7). Long-term follow-up radiographs and PROMs showed maintained improvements. (4) Conclusions: This series documents the first-recorded long-term corrections of lumbar spondylolisthesis and concomitant improvements in back pain, urinary urgency, and QOL using CBP®. This series provides evidence for CBP® as a non-surgical approach to lumbar spinal rehabilitation and the possible impacts of spinal alignment on pain, urinary dysfunction, and QOL.
Treating BCG-Induced Cystitis with Combined Chondroitin and Hyaluronic Acid Instillations in Bladder Cancer
Authors: Pichler Renate , Stäblein Johannes , Mari Andrea , Afferi Luca , D’Andrea David , Marcq Gautier , del Giudice Francesco , Soria Francesco , Caño-Velasco Jorge , Subiela José Daniel , Gallioli Andrea , Tully Karl H. , Mori Keiichiro , Herms Achim , Pradere Benjamin , Moschini Marco , Mertens Laura S. , Thurnher Martin
Published: March 2024

In non-muscle invasive bladder cancer, Bacillus Calmette–Guérin (BCG) responders benefit from strong Th1-type inflammatory and T cell responses mediating tumor rejection. However, the corresponding lack of anti-inflammatory Th2-type immunity impairs tissue repair in the bladder wall and facilitates the development of cystitis, causing urinary pain, urgency, incontinence, and frequency. Mechanistically, the leakage of the glycosaminoglycan (GAG) layer enables an influx of potassium ions, bacteria, and urine solutes towards the underlying bladder tissue, promoting chronic inflammation. Treatments directed towards re-establishing this mucopolysaccharide-based protective barrier are urgently needed. We discuss the pathomechanisms, as well as the therapeutic rationale of how chondroitin and hyaluronic acid instillations can reduce or prevent BCG-induced irritative bladder symptoms. Moreover, we present a case series of five patients with refractory BCG-induced cystitis successfully treated with combined chondroitin and hyaluronic acid instillations.
Efficacy and Safety of Combination Therapy with Low-Dose Rivaroxaban in Patients with Cardiovascular Disease: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
Authors: Bucci Tommaso , Del Sole Francesco , Menichelli Danilo , Galardo Gioacchino , Biccirè Flavio Giuseppe , Farcomeni Alessio , Lip Gregory Y. H. , Pignatelli Pasquale , Pastori Daniele
Published: March 2024

Objectives: To review the evidence on the effectiveness and safety of low-dose-rivaroxaban 2.5 mg twice daily (LDR) in patients with coronary artery disease (CAD) and/or peripheral artery disease (PAD) taking antiplatelets. Methods: We performed a systematic review and meta-analysis of randomized controlled trials (RCTs). Efficacy endpoints were cardiovascular events (CVEs), myocardial infarction, stroke, all-cause, and cardiovascular death. Any, major, fatal bleeding, and intracranial hemorrhage (ICH) were safety endpoints. Numbers needed to treat (NNT), and numbers needed to harm (NNH) were also calculated. Results: Seven RCTs were included with 45,836 patients: 34,276 with CAD and 11,560 with PAD. Overall, 4247 CVEs and 3082 bleedings were registered. LDR in association with either any antiplatelet drug or aspirin (ASA) alone reduced the risk of CVEs (hazard ratio [HR] 0.86, 95% confidence interval [95%CI] 0.78–0.94) and ischemic stroke (HR 0.68, 95%CI 0.55–0.84). LDR + ASA increased the risk of major bleeding (HR 1.71, 95%CI 1.38–2.11) but no excess of fatal bleeding or ICH was found. The NNT to prevent one CVE for LDR + ASA was 63 (43–103) and the NNH to cause major bleeding was 107 (77–193). Conclusions: The combination of LDR with either antiplatelet drugs or low-dose aspirin reduces CVEs and ischemic stroke in patients with CAD/PAD. There was an increased risk of major bleeding but no excess of fatal or ICH was found. LDR seems to have a favorable net clinical benefit compared to ASA treatment alone.
Comparative Analysis of Complication Rates in Tibial Shaft Fractures: Intramedullary Nail vs. Ilizarov External Fixation Method
Authors: Jeremic Danilo , Grubor Nikola , Bascarevic Zoran , Slavkovic Nemanja , Krivokapic Branislav , Vukomanovic Boris , Davidovic Kristina , Jovanovic Zelimir , Tomic Slavko
Published: March 2024

Background: The external fixation (EF) Ilizarov method, shown to offer efficacy and relative safety, has unique biomechanical properties. Intramedullary nail fixation (IMN) is an advantageous alternative, offering biomechanical stability and a minimally invasive procedure. The aim of this study was to assess outcomes in patients undergoing tibia fracture fixation, comparing the Ilizarov EF and IMN methods in an early phase of IMN implementation in Serbia. Methods: This was a retrospective study including patients with radiologically confirmed closed and open (Gustilo and Anderson type I) tibial diaphysis fractures treated at the Institute for Orthopedic Surgery “Banjica’’ from January 2013 to June 2017. The following demographic and clinical data were retrieved: age, sex, chronic disease diagnoses, length of hospital stay, surgical wait times, surgery length, type of anesthesia used, fracture, prophylaxis, mechanism of injury, postsurgical complications, time to recovery, and pain reduction. Pain intensity was measured by the Visual Analog Scale (VAS), a self-reported scale ranging from 0 to 100 mm. Results: A total of 58 IMN patients were compared to 74 patients who underwent Ilizarov EF. Study groups differed in time to recovery (p < 0.001), length of hospitalization (p = 0.007), pain intensity at the fracture site (p < 0.001), and frequency of general anesthesia in favor of intramedullary fixation (p < 0.001). A shorter surgery time (p < 0.001) and less antibiotic use (p < 0.001) were observed when EF was used. Additionally, we identified that the intramedullary fixation was a significant predictor of pain intensity. Conclusions: The IMN method offers faster recovery and reduced pain intensity in comparison to EF, while the length of surgery predicted the occurrence of any complication.
A Novel Viscoelastic Deformation Mechanism Uncovered during Vickers Hardness Study of Bone
Authors: Ibrahim Ahmed , Jiang Zhenting , Shirvani Khosro , Dalili Alireza , Abdel Hamid Z.
Published: March 2024

This study investigates the viscoelastic deformation mechanisms of bone as a response to Vickers hardness indentation. We utilized advanced high-resolution scanning electron microscopy (SEM) to investigate a distinct deformation pattern that originates from the indentation site within the bone matrix. The focus of our research was to analyze a unique deformation mechanism observed in bone tissue, which has been colloquially termed as “screw-like” due to its resemblance to a screw thread when viewed under an optical microscope. The primary goals of this research are to investigate the distinctive characteristics of the “screw-like” deformation pattern and to determine how the microstructure of bone influences the initiation and control of this mechanism. These patterns, emerging during the dwell period of indentation, underscore the viscoelastic nature of bone, indicating its propensity for energy dissipation and microstructural reconfiguration under load. This study uncovered a direct correlation between the length of the “screw-like” deformation and the duration of the indentation dwell time, providing quantifiable evidence of the bone’s viscoelastic behavior. This finding is pivotal in understanding the mechanical properties of bone, including its fracture toughness, as it relates to the complex interplay of factors such as energy dissipation, microstructural reinforcement, and stress distribution. Furthermore, this study discusses the implications of viscoelastic properties on the bone’s ability to resist mechanical challenges, underscoring the significance of viscoelasticity in bone research.
Influence of Magnesium Degradation on Schwannoma Cell Responses to Nerve Injury Using an In Vitro Injury Model
Authors: Bhat Krathika , Hanke Lisa , Helmholz Heike , Quandt Eckhard , Pixley Sarah , Willumeit-Römer Regine
Published: March 2024

Nerve guidance conduits for peripheral nerve injuries can be improved using bioactive materials such as magnesium (Mg) and its alloys, which could provide both structural and trophic support. Therefore, we investigated whether exposure to Mg and Mg-1.6wt%Li thin films (Mg/Mg-1.6Li) would alter acute Schwann cell responses to injury. Using the RT4-D6P2T Schwannoma cell line (SCs), we tested extracts from freeze-killed cells (FKC) and nerves (FKN) as in vitro injury stimulants. Both FKC and FKN induced SC release of the macrophage chemoattractant protein 1 (MCP-1), a marker of the repair SC phenotype after injury. Next, FKC-stimulated cells exposed to Mg/Mg-1.6Li reduced MCP-1 release by 30%, suggesting that these materials could have anti-inflammatory effects. Exposing FKC-treated cells to Mg/Mg-1.6Li reduced the gene expression of the nerve growth factor (NGF), glial cell line-derived neurotrophic factor (GDNF), and myelin protein zero (MPZ), but not the p75 neurotrophin receptor. In the absence of FKC, Mg/Mg-1.6Li treatment increased the expression of NGF, p75, and MPZ, which can be beneficial to nerve regeneration. Thus, the presence of Mg can differentially alter SCs, depending on the microenvironment. These results demonstrate the applicability of this in vitro nerve injury model, and that Mg has wide-ranging effects on the repair SC phenotype.
Advanced Planar Projection Contour (PPC): A Novel Algorithm for Local Feature Description in Point Clouds
Authors: Tang Wenbin , Lv Yinghao , Chen Yongdang , Zheng Linqing , Wang Runxiao
Published: March 2024

Local feature description of point clouds is essential in 3D computer vision. However, many local feature descriptors for point clouds struggle with inadequate robustness, excessive dimensionality, and poor computational efficiency. To address these issues, we propose a novel descriptor based on Planar Projection Contours, characterized by convex packet contour information. We construct the Local Reference Frame (LRF) through covariance analysis of the query point and its neighboring points. Neighboring points are projected onto three orthogonal planes defined by the LRF. These projection points on the planes are fitted into convex hull contours and encoded as local features. These planar features are then concatenated to create the Planar Projection Contour (PPC) descriptor. We evaluated the performance of the PPC descriptor against classical descriptors using the B3R, UWAOR, and Kinect datasets. Experimental results demonstrate that the PPC descriptor achieves an accuracy exceeding 80% across all recall levels, even under high-noise and point density variation conditions, underscoring its effectiveness and robustness.
Knowledge Distillation in Video-Based Human Action Recognition: An Intuitive Approach to Efficient and Flexible Model Training
Authors: Camarena Fernando , Gonzalez-Mendoza Miguel , Chang Leonardo
Published: March 2024

Training a model to recognize human actions in videos is computationally intensive. While modern strategies employ transfer learning methods to make the process more efficient, they still face challenges regarding flexibility and efficiency. Existing solutions are limited in functionality and rely heavily on pretrained architectures, which can restrict their applicability to diverse scenarios. Our work explores knowledge distillation (KD) for enhancing the training of self-supervised video models in three aspects: improving classification accuracy, accelerating model convergence, and increasing model flexibility under regular and limited-data scenarios. We tested our method on the UCF101 dataset using differently balanced proportions: 100%, 50%, 25%, and 2%. We found that using knowledge distillation to guide the model’s training outperforms traditional training without affecting the classification accuracy and while reducing the convergence rate of model training in standard settings and a data-scarce environment. Additionally, knowledge distillation enables cross-architecture flexibility, allowing model customization for various applications: from resource-limited to high-performance scenarios.
Analytical Model of Quantitative Texture Prediction Considering Heat Transfer Based on Single-Phase Material in Laser Powder Bed Fusion
Authors: Huang Wei , Wang Wenjia , Ning Jinqiang , Garmestani Hamid , Liang Steven Y.
Published: March 2024

Laser powder bed fusion (LPBF) is widely used in metal additive manufacturing to create geometrically complex parts, where heat transfer and its affected temperature distribution significantly influence the parts’ materials’ microstructure and the resulting materials’ properties. Among all the microstructure representations, crystallographic orientations play a paramount role in determining the mechanical properties of materials. This paper first developed a physics-based analytical model to predict the 3D temperature distribution in PBF considering heat transfer boundary conditions; heat input using point-moving heat source solutions; and heat loss due to heat conduction, convection, and radiation. The superposition principle obtained temperature distributions based on linear heat sources and linear heat loss solutions. Then, the temperature distribution was used to analytically obtain the texture grown on a substrate with random grain orientations considering columnar-to-equiaxed transition (CET). Thus, the link between process parameters and texture was established through CET models and physical rules. Ti-6Al-4V was selected to demonstrate the capability of the analytical model in a single-phase situation. By applying advanced thermal models, the accuracy of the texture prediction was evaluated based on a comparison of experimental data from the literature and past analytical model results. Hence, this work not only provides a method of the fast analytical simulation of texture prediction in the single-phase mode for metallic materials but also paves the road for subsequent studies on microstructure-affected or texture-affected materials’ properties for both academic research and industrial applications. The prediction of single-phase material texture has never been achieved before, and the scalability has been expanded.
The Initiation Characteristics of Corrosion Fatigue Crack in 18Ni (250) Steel
Authors: Pan Hongzhang , Zhu Yongmei , Fang Mingjiang
Published: March 2024

Maraging steel is the material of deep sea pressure equipment. The characteristics of corrosion fatigue crack initiation in 18Ni (250) were investigated by performing a tensile fatigue test under different loading conditions. The mechanism of corrosion fatigue crack initiation was analyzed considering the influence of welding. The results showed that the crack initiation life decreases with increasing load and increases with the stress ratio. In a corrosive seawater environment, crack initiation is affected by both mechanical damage and electrochemical corrosion. The proportion of the crack initiation life of the total sample life is approximately 71.45–99.55%, where the larger this proportion is, the smaller the fatigue zone is. Crack initiation and microcrack propagation in maraging steel correspond to the microfracture mechanism of dimple fractures. The microfracture mechanism is strongly affected by the presence of a weld but weakly affected by the weld position. The results of this study provide a theoretical basis for predicting the corrosion fatigue life of deep-sea submersible pressure hulls.
Thermo-Mechanical Coupling Analysis of the Sealing Structure Stress of LNG Cryogenic Hose Fittings
Authors: Yang Liang , Liu Miaoer , Liu Yun , Zhang Tao , Lu Hailong , Lu Qingzhen , Yan Jun
Published: March 2024

A cryogenic hose is used to transport liquefied natural gas at sea, where flexible fittings are sealed by corrugated lining and end flange welding. However, the extreme cryogenic temperatures of the conveyed fluid introduce substantial challenges to the integrity of the fitting seals’ structure during the LNG transfer process. In order to study the sealing performance of the fitting under LNG conveying conditions, this paper was based on the general finite element software ABAQUS 6.11 to carry out a thermo-mechanical coupling analysis of the end sealing stress. This paper also established a sealing performance analysis model of the corrugated fitting welding area under the fitting action of LNG load and internal pressure load. A sensitivity analysis was conducted on the influence of weld clearance, blunt edge size, and weld residual height on the weld stress of a fitting ring. The results show that, under the combined action of the medium internal pressure and cryogenic load, the size design of the weld area significantly affects the sealing performance of the fitting, among which the equivalent force of the weld clearance butt sealing area has the greatest impact. Moreover, it was found that a pressure of 5 MPa was 2 mm when the weld clearance was 2 mm, and the average stress at the weld was 53.68 MPa. Further, considering the synergistic influence of the blunt edge size, the weld clearance was 3 mm, the stress was minimal when the blunt side size was 4 mm, and the average stress was 17.42 MPa. These research results can serve as a reference for the design and analysis of the sealing structure of non-adhesive inner corrugated cryogenic hose fittings.
Research on Wave-Added Resistance and Longitudinal Stability Characteristics of Amphibious Aircraft in Rule Wave
Authors: Sun Huawei , Ju Anran , Chang Wentian , Liu Jingfei , Liu Jiayi , Sun Hanbing
Published: March 2024

Assessing the safety of amphibious aircraft hinges significantly on two key factors: wave-added resistance and motion stability during takeoff and landing on water surfaces. To tackle this, we employed the Reynolds-averaged Navier–Stokes (RANS) equations solved via the finite volume method. We utilized the volume fraction method to accurately capture the free surface and employed the overset grid technique to manage the relative motion between the aircraft and the liquid surface. Our approach involves establishing a numerical simulation scheme to investigate the water-planing motion of amphibious aircraft across varying wave heights, wavelengths, speeds, and center-of-gravity positions. The computational findings demonstrate a close match between calculated forces and aircraft motion compared to experimental values. Notably, we observed pronounced nonlinearity in wave-added resistance. Under high sea conditions, operating in a short-wavelength environment or with a rearward center-of-gravity position proves advantageous for reducing wave-added resistance. Conversely, poor longitudinal stability is evident during planing in long waves.
A Ship Path Tracking Control Method Using a Fuzzy Control Integrated Line-of-Sight Guidance Law
Authors: Han Bing , Duan Zaiyu , Peng Zhouhua , Chen Yuhang
Published: March 2024

A fuzzy control improvement method is proposed with an integral line-of-sight (ILOS) guidance principle to meet the needs of autonomous navigation and high-precision control of ship trajectories. Firstly, a three-degree-of-freedom ship motion model was established with the battery-powered container ship ZYHY LVSHUI 01 built by the COSCO Shipping Group. Secondly, a ship path-following controller based on the ILOS algorithm was designed. To satisfy the time-varying demand of the look-ahead distance parameters during the following process, especially under different navigation conditions, fuzzy logic controllers were designed for different navigation conditions to automatically adjust the look-ahead distance parameters. Thirdly, a controller was applied that uses a five-state extended Kalman filter (EKF) to estimate the heading, speed, and heading rate based on the ship’s motion model with the assistance of Global Navigation Satellite System (GNSS) position measurements. This provides the necessary navigational information, reduces the algorithm’s dependence on sensors, and improves its generalizability. Finally, path-following experiments were carried out in the MATLAB experimental platform, and the results were compared with different following algorithms. The simulation results showed that the new algorithm has a better following performance, and it can maintain a smooth rudder angle output. The research results provide a reference for the path-following control of ships.
Analysis of Unsteady Flow Characteristics Near the Cutwater by Cutting Impeller Hub in a High-Speed Centrifugal Pump
Authors: Cui Baoling , Shi Mingyu
Published: March 2024

Centrifugal pumps are essential fluid transfer devices in marine engineering. As the two most critical components of a centrifugal pump, the dynamic–static interference between the volute and the impeller makes the flow near the cutwater highly unstable, with significant and erratic pressure pulsation, which seriously affects the stability of the operation. The impeller can be improved by cutting the hub, which helps stabilize the flow and reduce pressure pulsation near the cutwater, thus minimizing hydraulic loss. In this study, four different cutting angles were applied to the impeller hub. Computations are conducted using large eddy simulation to analyze the flow and pressure pulsation near the cutwater. Compared to the prototype pump, the modified impeller exhibits a significant reduction in pressure gradient near the blade outlet close to the cutwater. The modified impeller also shows a more uniform flow and lower amplitude of pressure pulsation. Furthermore, under various flow conditions, the centrifugal pump with the modified impeller exhibits lower hydraulic loss compared to the prototype pump, indicating that this method effectively suppresses hydraulic loss.
Mobile_ViT: Underwater Acoustic Target Recognition Method Based on Local–Global Feature Fusion
Authors: Yao Haiyang , Gao Tian , Wang Yong , Wang Haiyan , Chen Xiao
Published: March 2024

To overcome the challenges of inadequate representation and ineffective information exchange stemming from feature homogenization in underwater acoustic target recognition, we introduce a hybrid network named Mobile_ViT, which synergizes MobileNet and Transformer architectures. The network begins with a convolutional backbone incorporating an embedded coordinate attention mechanism to enhance the local details of inputs. This mechanism captures the long-term temporal dependencies and precise frequency–domain relationships of signals, focusing the features on the time–frequency positions. Subsequently, the Transformer’s Encoder is integrated at the end of the backbone to facilitate global characterization, thus effectively overcoming the convolutional neural network’s shortcomings in capturing long-range feature dependencies. Evaluation on the Shipsear and DeepShip datasets yields accuracies of 98.50% and 94.57%, respectively, marking a substantial improvement over the baseline. Notably, the proposed method also demonstrates obvious separation coefficients, signifying enhanced clustering effectiveness, and is lighter than other Transformers.
Investigations of the Formation Mechanism and Pressure Pulsation Characteristics of Pipeline Gas-Liquid Slug Flows
Authors: Zheng Gaoan , Xu Pu , Li Lin , Fan Xinghua
Published: March 2024

The pipeline system is widely used in marine engineering, and the formation mechanism and flow patterns of two-phase slug flows are of great significance for the optimal design of and vibration prevention in a complex pipeline system. Aiming at the above problems, this paper proposes a modeling and solving method for gas-liquid slug flows. First, a VOF-PLIC-based coupling gas-liquid slug flow transport model is conducted. Second, to reduce the fuzzy boundary between the gas-liquid coupling interfaces, an artificial compression term is added to the transport equations, and the formation and evolution mechanism of severe slugging flow in piping systems is investigated. The pressure pulsation and gas content characteristics of the gas-liquid coupling process are explored. Research results found that the slugging phenomenon occurs at the gas-liquid interface, where liquid slugging frequency reaches its peak. The pipeline system has prominent periodic characteristics of the slugging phenomenon, and the period decreases when the gas-phase converted speed rises; pressure fluctuation amplitude increases, and the gas-phase velocity change is the inducing factor for the drastic change of pressure fluctuation. The research results can offer theoretical references for optimal designs of and vibration prevention in marine pipeline systems.
Trajectory of Particulate Waste Transported by Artificial Upwelling
Authors: Wen Caining , Fan Wei , Xiao Canbo , Zhao Yonggang , Hu Shicheng , Yue Lulu , Qu Mengjie , Chen Ying
Published: March 2024

The feeding activities of fish in marine aquaculture have raised concerns about severe benthic pollution within the cage area. This paper suggests removing particulate waste from the cage area through the implementation of artificial upwelling (AU), a method likely to alleviate the organic burden within the cultivation area. A numerical model was developed to simulate AU-induced particulate matter transport under different operating conditions, with the majority of simulation results validated through flume experiments. The influence of particle characteristics, environmental conditions, and engineering parameters of AU on organic matter transport are discussed. In particular, our study offers a detailed analysis of the minimum initial upwelling velocity required to transport particulate waste to a designated distance. It also recommends situating the bottom of the cage above the maximum height of the waste plume to effectively segregate fish from the waste carried by the upwelling.
A Machine Learning Technique for Deriving the Optimal Mesh Size of a Gizzard Shad (Konosirus punctatus) Gillnet
Authors: Koo Myungsung , Kwon Inyeong
Published: March 2024

Gizzard shads are facing a continual decline in population, necessitating the implementation of selective gear design for effective resource management. This study aims to prevent the bycatch of young gizzard shads, a non-target fish species, and to derive mesh sizes appropriate for fishery management. Experimental fishing (n = 11) was conducted by manufacturing gillnet fishing gear with different mesh sizes (50.5, 55.1, 60.6, and 67.3 mm) in the coastal waters of the southern Gyeongsang Province. Two methods were employed to estimate the appropriate mesh size of the shad gillnet as follows: firstly, by analyzing the selectivity curve based on body length data; secondly, by developing a complex machine learning model considering biological and economic factors. Model 1 was constructed using mesh variables to classify the score groups. As a result of this study, the total length with a 0.5 gillnet selection ratio. which was estimated to be 179.3, 195.6, 215.1, and 238.9 mm for the 50.5, 55.1, 60.6, and 67.3 mm mesh sizes, respectively. In Model 1, a mesh size of 57.85 mm or less was determined as the most appropriate mesh size. Therefore, considering both biological and economic aspects, shad gillnets should have a mesh size in the 50.5 to 55.1 mm range.