Search Results (1,861)

Background/Objectives: The effectiveness of clear aligner therapy depends significantly on the precision of force delivery through the aligner–attachment interface. This study aimed to evaluate the microscopic compatibility between different orthodontic clear aligner materials (Duran+ and Zendura FLX) and attachment designs (rectangular and optimized) using scanning electron microscopy (SEM). Methods: Fifty-six samples were divided into four groups: rectangular attachments with Duran+ aligners (n = 14), rectangular attachments with Zendura FLX aligners (n = 14), optimized attachments with Duran+ aligners (n = 14), and optimized attachments with Zendura FLX aligners (n = 14). Attachments were bonded to bovine incisors using standardized protocols. Clear aligners were thermoformed at 220 °C for 40 s. Cross-sectional samples were analyzed using SEM at 250× magnification. Gap measurements were taken at seven points for rectangular attachments and five points for optimized attachments. Results: Gap measurements ranged from 14.75 ± 1.41 µm to 91.07 ± 3.11 µm. Zendura FLX demonstrated significantly better adaptation than Duran+ with rectangular attachments (42.10 ± 1.07 µm vs. 44.52 ± 1.51 µm, p < 0.001). Optimized attachments showed better overall adaptation than rectangular attachments. All combinations showed regional variation with the largest gaps at gingival borders (67.18–91.07 µm) and the smallest at flat buccal surfaces (14.75–20.98 µm). Conclusions: Perfect adaptation was not achieved with any material–attachment combination tested. Material selection and attachment design significantly influence microscopic adaptation, with multi-layer materials and optimized geometries showing superior performance. These findings provide mechanical explanations for clinical limitations in clear aligner therapy. Full article

Background and objectives: Mental health issues such as anxiety and stress are prevalent in educational settings, highlighting the need for individualized, scalable interventions. Mind–body approaches are promising for distress management, and this study explored which body-based strategies students found effective. Methods: A cross-sectional study assessed mental health and the use of body-based coping strategies among 152 primarily female students, age 21–52, in the Educational Program for Psychomotor Therapy, a group familiar with such strategies. An electronic survey assessed well-being (WHO-5), stress (PSS-10), anxiety (HADS-A), and use of 13 mind–body practices (e.g., breathing, grounding, muscle relaxation). Participants were grouped by mental health risk and a logistic regression explored associations with coping strategy use. Results: High-frequency use of more body-based strategies predicted lower odds of being in the high-risk group (p = 0.039), while sporadic use of more strategies predicted high mental health risk (p = 0.022). Breathing and grounding were the most frequently used and helpful practices, with minimal barriers. High-risk students cited capability concerns and time as barriers, while all participants mentioned forgetting to use the practices. Conclusions: High-risk students use a broader range of practices sporadically, whereas low-risk students adopt selected strategies more consistently. Proper integration of practices through education and training may be crucial for enhancing their efficacy. Full article

Background: Non-alcoholic fatty liver disease (NAFLD) is a global public health issue. Although liver biopsy remains the gold standard for diagnosing hepatosteatosis, its invasiveness, high cost, and associated risks limit its widespread use. Therefore, there is a need for reliable, non-invasive, and cost-effective biomarkers to aid in the early detection of NAFLD. Our objective was to determine the utility of the triglyceride (TG)-to-high-density-lipoprotein (HDL) ratio in predicting non-alcoholic fatty liver disease. Methods: This retrospective cross-sectional study included 2588 patients who met the inclusion criteria. Demographic data and laboratory results were collected from electronic health records. Experienced radiologists performed abdominal ultrasonography to assess fatty liver according to the EASL 2021 criteria. The TG/HDL ratio and other non-invasive scores (APRI, FIB-4, ALT/AST, TG/glucose) were calculated. Early-stage disease was defined as grade 1 or grade 2 hepatosteatosis. Results: The TG/HDL ratio was significantly higher in NAFLD patients (AUROC: 0.682) and outperformed the other non-invasive indices. At the optimal cut-off value of 1.86, the sensitivity was 80.7%, and the specificity was 45.5%. The TG/HDL ratio correlated positively with markers of glycemic control, inflammation, and liver enzymes. Conclusions: The TG/HDL ratio is an accessible and valuable parameter for predicting non-alcoholic fatty liver disease. It offers a non-invasive alternative to liver biopsy and potentially prevents complications from non-alcoholic fatty liver disease or diagnostic approaches. Full article

This paper investigates the suppression of the cohesive cracking mode (CCM) in the sintered silver (s-Ag) die layer by intentionally introducing anisotropic porosity through two press sintering methods. Full press (FP) and local press (LP) bonding represent the s-Ag formed by pressing the die-attached assemblies (DAAs) on either the entire top surface or only on the silicon carbide (SiC) top surface, respectively. The fabricated DAAs were encapsulated with epoxy molding compounds. Degradation was evaluated using a nine-point bending test (NBT) under cyclic force between 0 and 270 N with a triangle waveform for 3 min per cycle at 150 °C. Scanning tomography images after 500 NBT cycles showed that the LP reduced the inner degradation ratio by up to 21.1% compared to the FP. Cross-sectional scanning electron microscopy revealed that the FP progressed cracking in the s-Ag die layer, whereas the LP showed no evidence of cracking. A finite element analysis revealed that in the FP, the accumulated plastic strain (APS) was concentrated in the s-Ag layer within the inner SiC chip. In contrast, the APS of the LP was preferentially concentrated outside the SiC chip. This preferential localization of damage outside the chip presents a promising approach for enhancing the reliability of packaging products. Full article

Single-crystal 4H silicon carbide (4H-SiC) is a key substrate material for third-generation semiconductor devices, where surface and subsurface integrity critically affect performance and reliability. This study systematically examined the evolution of surface morphology and subsurface damage (SSD) during nanoscratching of 4H-SiC under varying normal loads (0–100 mN) using a nanoindenter equipped with a diamond Berkovich tip. Scratch characteristics were assessed using scanning electron microscopy (SEM), while cross-sectional SSD was characterised via focused ion beam (FIB) slicing and transmission electron microscopy (TEM). The results revealed three distinct material removal regimes: ductile removal below 14.5 mN, a brittle-to-ductile transition between 14.5–59.3 mN, and brittle removal above 59.3 mN. Notably, substantial subsurface damage—including median cracks exceeding 4 μm and dislocation clusters—was observed even within the transition zone where the surface appeared smooth. A thin amorphous layer at the indenter-substrate interface suppressed immediate surface defects but promoted subsurface damage nucleation. Crack propagation followed slip lines or their intersections, demonstrating sensitivity to local stress states. These findings offer important insights into nanoscale damage mechanisms, which are essential for optimizing precision machining processes to minimise SSD in SiC substrates. Full article

Tomicus yunnanensis, a notorious forest pest in southwest China, primarily employs infochemicals to coordinate mass attacks that overcome host tree defenses. However, secondary visual cues, particularly detection of host color changes, also aid host location. This study characterized the compound eye structure and vision of T. yunnanensis using electron microscopy and phototaxis tests. The apposition eye contains 224–266 ommatidia, with asymmetry between left and right. Quadrilateral facets occupy the dorsal third, while hexagonal facets dominate elsewhere. Each ommatidium comprises a large corneal lens, an acone-type crystalline cone from four cone cells, and an open-type rhabdom formed by eight retinular cells (R7–R8 centrally, R1–R6 peripherally), surrounded by two primary and at least seventeen secondary pigment cells. Dark/light adaptation alters cone size/shape and rhabdom cross-sectional area/outline (without pigment granule movement) to regulate light reaching the photoreceptors. Behavioral observations showed peak flight activity occurs between 7:00–11:00 AM, with no nighttime activity. Phototaxis tests revealed females are highly sensitive to 360 nm, 380 nm, and 700 nm wavelengths, while males exhibit high sensitivity to 360 nm and 400 nm. This work enhances knowledge on the integration of visual and olfactory sensory information in beetles for host location and non-host avoidance. Full article

Background: The growing challenge of multimorbidity for healthcare systems worldwide demands a dual prevention framework, targeting both primary and secondary prevention. Multimorbidity–multibehaviours can provide such a theoretical and clinical framework to explore new aetiological evidence for multimorbidity risk. While the role of single health risk behaviours, such as smoking, nutrition, alcohol, and physical activity (SNAP), in chronic disease prevention is well-documented, their synergistic effect on multimorbidity has received relatively little attention. Methods: Using retrospective observational data from electronic health records of 21,079 patients from a convenience sample of three general practices in Staffordshire, UK (2015–2018), we examined the association between SNAP-multibehaviours and multimorbidity risk, defined as follows: MM2+ (≥2 morbidities), MM3+ (≥3 morbidities), and complex multimorbidity (accumulated morbidities affecting ≥3 body systems). Multiple logistic regression models, stratified by sex and adjusted for age and area, were applied to analyse the associations between both combined and accumulative SNAP-health risk behaviours (HRBs) and all multimorbidity operational definitions. Results: A dose–response association was observed, indicating increased multimorbidity risk with greater accumulation of SNAP-HRBs. Additionally, sex-specific patterns were identified, which varied according to the operational definitions of multimorbidity. These findings underscored both the clinical significance of the identified outcomes for promoting tailored multimorbidity guidelines and the need for further sex-sensitive research. Conclusion: These findings support the importance of transcending traditional silos in healthcare and public health research by integrating preventive and curative medicines under a multimorbidity–multibehaviour framework. Embracing the complexity of coexisting morbidities and health risk behaviours, healthcare systems can move beyond disease-specific and behaviour-specific paradigms. This approach has the potential to enhance clinical outcomes and to address the complex needs of individuals with multimorbidity in real-world healthcare settings. Full article

Background/Objectives: Electronic cigarettes (e-cigarettes) have gained popularity among young adults globally, but only limited research exists on usage patterns in Saudi Arabia. This study investigated the prevalence, patterns, and factors associated with e-cigarette use initiation and transition to cigarette smoking among university students in Saudi Arabia. Methods: A cross-sectional survey was conducted among 537 university students in Al-Madinah city during the 2024–2025 academic year. Data were collected using a self-administered online questionnaire assessing e-cigarette use patterns, motivations, susceptibility to future cigarette smoking, and demographic characteristics. Multivariable logistic regression analysis was used to identify factors associated with e-cigarette use. Results: E-cigarette prevalence was substantial: 11.7% of participants were current users, 5.4% were former users, and 27.9% were ever-users, compared with 5.8% current cigarette smokers. Males had significantly higher use rates than females (20.9% vs. 4.6%; p < 0.001). Senior students showed the highest current use (21.1%). Among ever-users, the primary motivations were enjoyment (29.3%), the possibility of use where smoking is banned (26.1%), and social acceptability (21.7%). Most users (73.0%) used high-nicotine liquids (≥20 mg/mL), and 55.4% vaped daily. Multivariable logistic regression revealed that e-cigarette use was independently associated with male gender (adjusted OR = 4.0), higher academic year (OR = 1.24), current smoking (adjusted OR = 3.45; 95 CI: 1.54–7.82), and lower harm perception (adjusted OR = 1.69; 95 CI: 1.16–2.51). Susceptibility to future cigarette smoking was 18.9% overall but much higher among current e-cigarette smokers (59.5%; p < 0.001). Conclusions: E-cigarette use was prevalent among Saudi university students, particularly males and senior students, with patterns suggestive of nicotine dependence. Strong associations with cigarette smoking and high-concentration nicotine use raise concerns about dual use and addiction potential. Full article

Electron beam physical vapor deposited (EB-PVD) thermal barrier coatings (TBCs) are widely used to protect the hot section parts of aircraft engine turbines due to its uniform columnar microstructure and high strain tolerance. The microstructure and thermal shock life of 7 wt% Y₂O₃ stabilized zirconia (YSZ) coatings produced by EB-PVD were investigated as a function of oxygen gas flow during deposition. The surface and cross-section microstructure of EB-PVD YSZ coatings were highly influenced by the oxygen gas flow. When the oxygen gas flow is less than 60 sccm, a sandwich is formed between the bond coat (BC) layer and the YSZ layer, which significantly reduces the thermal shock life of the coating. Full article

Chromium–aluminum nitride (CrAlN) coatings were deposited on polished H13 tool steel substrates using direct current (DC) magnetron sputtering. The Cr/Al composition in the target was varied by inserting either four or eight chromium (Cr) plugs into cavities machined into an aluminum (Al) plate target. Nitrogen was introduced as a reactive gas to facilitate the formation of the nitride phase. Coatings were deposited at substrate bias voltages of −30 V, −50 V, and −60 V to study the combined effects of composition and ion energy on coating properties. Compositional analysis of coatings deposited at a −50 V bias revealed Cr/Al ratios of approximately 0.8 and 1.7 for the 4- and 8-plug configurations, respectively. This increase in the Cr/Al ratio led to a 2.6-fold improvement in coating hardness. Coatings produced using the eight-Cr-plug target exhibited a nearly linear increase in hardness with increasing substrate bias voltage. Cross-sectional scanning electron microscopy revealed a uniform bilayer structure consisting of an approximately 0.5 µm metal interlayer beneath a 2–3 µm CrAlN coating. Surface morphology analysis indicated the presence of coarse microdroplets in coatings with the lower Cr/Al ratio. These microdroplets were significantly suppressed in coatings with higher Cr/Al content, especially at increased bias voltages. This suppression is likely due to enhanced ion bombardment associated with the increased Cr content, attributed to Cr’s relatively higher atomic mass compared to Al. Coatings with lower hardness exhibited greater scratch resistance, likely due to the influence of residual compressive stresses. The findings highlight the critical role of both Cr/Al content and substrate bias in tailoring the tribo-mechanical performance of PVD CrAlN coatings for wear-resistant applications. Full article

Ferronickel slag and ground granulated blast-furnace slag (GGBFS) are solid waste by-products from the metallurgical industry. When incorporated into concrete, they help promote resource utilization, reduce hydration heat, and lower both solid waste emissions and the carbon footprint. To facilitate the application of ferronickel slag–GGBFS concrete in 3D printing, this study examines how aggregate size and nozzle diameter affect its performance. The investigation involves in situ printing, rheological characterization, mechanical testing, and scanning electron microscopy (SEM) analysis. Results indicate that excessively large average aggregate size negatively impacts the smooth extrusion of concrete strips, resulting in a cross-sectional width that exceeds the preset dimension. Excessively small average aggregate size results in insufficient yield stress, leading to a narrow cross-section of the extruded strip that fails to meet printing specifications. The extrusion performance is closely related to both the average aggregate size and nozzle diameter, which can significantly influence the normal extrusion stability and print quality of 3D printed concrete strips. The thixotropic performance improves with an increase in the aggregate size. Both compressive and flexural strengths improve with increasing aggregate size but decrease with an increase in the printing nozzle size. Anisotropy in mechanical behavior decreases progressively as both parameters mentioned increase. By examining the cracks and pores at the interlayer interface, this study elucidates the influence mechanism of aggregate size as well as printing nozzle parameters on the mechanical properties of 3D printed ferronickel slag–GGBFS concrete. This study also recommends the following ranges. When the maximum aggregate size exceeds 50% of the nozzle diameter, smooth extrusion is not achievable. If it falls between 30% and 50%, extrusion is possible but shaping remains unstable. When it is below 30%, both stable extrusion and good shaping can be achieved. Full article

Background: Burnout syndrome (BS) is an occupational phenomenon resulting from chronic workplace stress that has not been successfully managed. Although there are underlying causes associated with personal attributes, it is generally linked to external factors within the work environment. The aim of the present study was to investigate the impact of lifestyle factors on BS and its dimensions, as well as on suicidal ideation among Spanish professionals dedicated to implant dentistry. Methods: A cross-sectional observational study was conducted in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines. An electronic survey based on the Maslach Burnout Inventory—Human Services Survey (MBI–HSS) was distributed to members of the Spanish Society of Implants. The data were analysed using descriptive statistical methods. Results: A total of 305 participants (20.9%) responded to the questionnaire. Notably, 10.8% of the professionals reported experiencing suicidal thoughts, a factor significantly associated with the presence of BS. The lifestyle factors associated with BS included the following: not engaging in aerobic exercise for at least 30 min per day (p < 0.05), not having hobbies that facilitate mental disconnection from work (p < 0.001), not following a balanced diet (p < 0.0001), having an insufficient social life (p < 0.0001), and experiencing suicidal ideation (p < 0.01). Conclusions: The surveyed dentists generally reported having healthy lifestyle habits. Nevertheless, one in ten professionals acknowledged having experienced suicidal ideation at some point, highlighting a concerning association with BS. Full article

Background and Objectives: Although survival after congenital cardiac malformations (CCM) has improved, little is known about Romanian children’s own perceptions of health-related quality of life (HRQoL) or their emotional burden. We compared HRQoL, depressive symptoms, and anxiety across lesion severity strata and explored clinical predictors of impaired HRQoL. Methods: In this cross-sectional study (1 May 2023–30 April 2025), 72 children (mean age 7.9 ± 3.0 years, 52.8% male) attending a tertiary cardiology clinic completed the Romanian-validated Pediatric Quality of Life Inventory (PedsQL), Children’s Depression Inventory (CDI) and the Screen for Child Anxiety-Related Emotional Disorders questionnaire (SCARED-C, child version). Lesions were classified as mild (n = 22), moderate (n = 34), or severe (n = 16). Left-ventricular ejection fraction (LVEF) and unplanned cardiac hospitalisations over the preceding 12 months were extracted from electronic records. Results: Mean PedsQL total scores declined stepwise by severity (mild 80.9 ± 7.3; moderate 71.2 ± 8.4; severe 63.1 ± 5.4; p < 0.001). CDI and SCARED-C scores rose correspondingly (CDI: 9.5 ± 3.0, 13.6 ± 4.0, 18.0 ± 2.7; anxiety: 15.2 ± 3.3, 17.2 ± 3.8, 24.0 ± 3.4; both p < 0.001). PedsQL correlated positively with LVEF (r = 0.51, p < 0.001) and negatively with hospitalisations (r = −0.39, p = 0.001), depression (r = −0.44, p < 0.001), and anxiety (r = −0.47, p < 0.001). In multivariable analysis, anatomical severity remained the sole independent predictor of lower HRQoL (β = −8.4 points per severity tier, p < 0.001; model R² = 0.45). Children with ≥ 1 hospitalisation (n = 42) reported poorer HRQoL (69.6 ± 8.0 vs. 76.1 ± 11.1; p = 0.005) and higher depressive scores (p < 0.001). Conclusions: HRQoL and internalising symptoms in Romanian children with CCM worsen with increasing anatomical complexity and recent hospital utilisation. The severity tier outweighed functional markers as the main determinant of HRQoL, suggesting that psychosocial screening and support should be scaled to lesion complexity. Integrating the routine use of the Romanian-validated PedsQL, CDI, and SCARED-C questionnaire into cardiology follow-up may help identify vulnerable patients early and guide targeted interventions. Full article

The incorporation of digital health into the medical curricula is becoming more important to better prepare doctors in the future. Digital health comprises a wide range of tools such as electronic health records, health information technology, telemedicine, telehealth, mobile health applications, wearable devices, artificial intelligence, and virtual reality. The present study aimed to explore the medical and biomedical students’ perspectives on the integration of digital health in medical curricula. A cross-sectional study was conducted on the medical and biomedical undergraduate students at the College of Medicine and Health Sciences at Sultan Qaboos University. Data was collected using a self-administered questionnaire. The response rate was 37%. The majority of respondents were in the MD (Doctor of Medicine) program (84.4%), while 29 students (15.6%) were from the BMS (Biomedical Sciences) program. A total of 55.38% agreed that they were familiar with the term ‘e-Health’. Additionally, 143 individuals (76.88%) reported being aware of the definition of e-Health. Specifically, 69 individuals (37.10%) utilize e-Health technologies every other week, 20 individuals (10.75%) reported using them daily, while 44 individuals (23.66%) indicated that they never used such technologies. Despite having several benefits, challenges exist in integrating digital health into the medical curriculum. There is a need to overcome the lack of infrastructure, existing educational materials, and digital health topics. In conclusion, embedding digital health into medical curricula is certainly beneficial for creating a digitally competent healthcare workforce that could help in better data storage, help in diagnosis, aid in patient consultation from a distance, and advise on medications, thereby leading to improved patient care which is a key public health priority. Full article

Background/Objectives: The consumption of opioids is a public health problem that significantly affects quality of life. In Spain, 7585 people are enrolled in the Methadone Maintenance Programme (MMP), which is an effective intervention with a low adherence rate. In this study, factors associated with the quality of life of MMP users, especially perceived social support and treatment adherence, were analysed. We hypothesised that low levels of adherence and social support would be associated with poorer quality of life. Methods: This was a cross-sectional observational study with an analytical approach. Quality of life (WHOQoL-BREF), perceived social support (DUKE-UNC-11), and treatment adherence (MMAS-8) among MMP users were studied, and data on sociodemographic and clinical characteristics were collected through ad hoc questionnaires and a review of electronic medical records. Linear and logistic regression models were used. Results: A total of 70 individuals were included in this study. The mean age was 56.9 years, and 83% of the participants were male. The perceived quality of life was low in the four domains evaluated (range of 47.4–48.2). A total of 38.57% of the participants had low perceived social support. Treatment adherence was low or moderate in 77.1% of the participants. Greater perceived social support was associated with better quality of life in all domains (p < 0.05). Quality of social life was negatively associated with the use of nonbenzodiazepine neuroleptics and HIV status. Treatment adherence was lower in insulin therapy users. Conclusions: Social support is a key determinant of the quality of life of MMP users. Health policies should promote social support networks as a strategy to improve the well-being of this population. Full article