Search Results (790)

This study investigates the residual stresses developed during the curing process of polymer fiber-reinforced composites and their influence on fracture behavior, particularly the initiation and propagation of interlaminar cracks. The main objective is to quantify how different curing histories, including incomplete cure, alter the spatial distribution of residual stresses and, in turn, affect the mode-I fracture response of carbon-fiber/epoxy laminates. A transient thermal–structural finite element framework incorporating an autocatalytic cure kinetics model was used to simulate the curing process and predict residual stress development in a unidirectional carbon-fiber/epoxy laminate with an edge crack, considering thermal, chemical, and geometric effects. The cure model was calibrated using isothermal differential scanning calorimetry data to determine the degree of cure under different thermal conditions. The key novelty of this work is the integration of a validated cure-kinetics-based curing simulation with fracture analysis, enabling direct correlation of thermal history and degree of cure with spatially varying residual stresses at the crack front and their effect on fracture toughness. Numerical load–displacement predictions were compared with double cantilever beam experimental results and showed good agreement for the curing profiles examined. The results demonstrate that residual stresses generated by different cure cycles, including hold conditions and incomplete curing, significantly influence fracture toughness. In particular, the incomplete-cure profile produced an approximately 40% reduction in toughness compared with profiles that achieved complete cure, highlighting the importance of cure history in determining final structural performance. Full article

Background: Drug-resistant tuberculosis (DR-TB) remains a major public health challenge in South Africa, particularly in rural settings with high HIV co-infection rates. Understanding predictors of treatment response among people living with HIV is essential for improving clinical management and programmatic outcomes. This study aimed to identify socio-demographic and clinical predictors of treatment outcomes among HIV-positive individuals diagnosed with multidrug-resistant (MDR) and extensively drug-resistant tuberculosis (XDR-TB) in rural Eastern Cape Province, South Africa. Methods: A retrospective cohort study was conducted using routinely collected clinical records of DR-TB patients initiated on treatment between January 2020 and December 2024 at two public healthcare facilities. A total of 239 patients with complete treatment outcome data were included. Treatment outcomes were classified as favourable (cured or treatment completed) or unfavourable (death, treatment failure, or loss to follow-up). Descriptive statistics were used to summarise patient characteristics, while univariate and multivariable logistic regression analyses were performed to identify factors associated with treatment outcomes. Results: Most participants were aged ≤ 39 years (58%), male (60%), unemployed (90%), and without income (80%). MDR-TB accounted for 40% of cases, rifampicin-resistant-TB (RR-TB) for 53%, and XDR-TB for 7.1%. Multivariable analysis showed that XDR-TB was the strongest independent predictor of unfavourable treatment outcome (AOR = 0.18; 95% CI: 0.06–0.58; p = 0.004). Income status was also significantly associated with outcome, with participants reporting some incomes having lower odds of favourable outcomes (AOR = 0.46; 95% CI: 0.23–0.92; p = 0.036). The model demonstrated modest predictive performance (AUC = 0.67). Conclusions: These findings highlight the dominant influence of resistance phenotype, particularly XDR-TB, on treatment prognosis among HIV-positive DR-TB patients in rural Eastern Cape. Integrating early resistance profiling, intensified clinical management of XDR-TB, and socioeconomic support mechanisms may improve treatment outcomes in high-burden rural settings. Full article

The objective was to investigate the effect of an adhesive-enhancing primer (AEP) on the shear bond strength (SBS) between fresh resin composite and aged resin composite interface, specifically considering the presence or absence of saliva contamination on the aged resin composites. One hundred fifty-three resin composite blocks underwent thermocycling to replicate aging. Nine groups (n = 15) formed: Group 1: no saliva + no surface treatment; Group 2: no saliva + AEP; Group 3: no saliva + bonding agent; Group 4: no saliva + AEP + bonding agent; Group 5: saliva + no surface treatment; Group 6: saliva + AEP; Group 7: saliva + bonding agent; Group 8: saliva + AEP + bonding agent; and Group 9: saliva + phosphoric acid + bonding agent. Fresh resin composite was applied to the surface of each sample and then light-cured. All specimens were stored for 24 h in distilled water at 37 °C. The SBS testing and failure modes were assessed next. One-way ANOVA and the Tukey test (α = 0.05) were used. Group 9 had the highest SBS (15.42 ± 1.37 MPa) but did not significantly differ from Groups 3, 4, 7, and 8 (p > 0.05). Group 5 showed the lowest SBS (3.08 ± 0.41 MPa). Additionally, group 1 demonstrated significantly lower SBS than all other groups except group 5 (p < 0.001). Groups 2 and 6 exhibited comparable SBS (p > 0.05). Groups 3, 4, 7, 8, and 9 displayed both adhesive and mixed failure, whereas the other groups demonstrated a complete adhesive failure. Regardless of saliva contamination, AEP improved the bond strength at the interface between the fresh resin composite and the aged resin composite. Full article

This study evaluates the effectiveness of microfine cement (MF) to seal two laboratory-fabricated wellbore microannuli. The samples were characterized with their hydraulic apertures (158 and 85 µm). A rough cement surface paired with a transparent acrylic plate, acting as a steel surrogate, formed the basis of the experimental setup, with the acrylic enabling direct visual monitoring of MF behavior throughout the tests. Hydraulic aperture measurements were taken before and after each repair attempt, with MF injected at constant pressure and a 24 h curing period allowed between successive injections. Four injection cycles were completed per sample. The MF cement had a d₉₅ = ~14 µm and a w/c of 1.45. Results show progressive reduction in hydraulic aperture from 158 µm to 20 µm and from 85 µm to 8 µm, but complete sealing was not achieved. Visual observations revealed that bleeding and filtration (plug formation) were the primary mechanisms limiting repair efficiency. These findings highlight the challenges of sealing rough microannuli with MF and suggest that aperture variability and particle filtration strongly influence repair outcomes. Higher injection pressures or alternative materials may be required for complete sealing. Full article

Background/Objectives: Renal cell carcinoma (RCC) with venous tumor thrombus (VTT) extending into the inferior vena cava (IVC) occurs in 4–10% of patients and represents one of the most technically demanding scenarios in urologic surgery. Open radical nephrectomy with en bloc thrombectomy remains the gold standard for infradiaphragmatic disease (Mayo Levels 0–III), offering the only realistic prospect for long-term cure. This narrative review provides a technically oriented, evidence-based guide for surgical urologists managing these complex cases. Methods: PubMed/MEDLINE, Scopus, and Web of Science were searched (1970–March 2025) using terms related to RCC, venous tumor thrombus, IVC thrombectomy, and perioperative management. Priority was given to prospective studies, systematic reviews, large retrospective cohorts, and current guidelines (EAU 2025, NCCN v2.2024). Original intraoperative photographs supplement procedural descriptions. Results: We detail the complete perioperative pathway: VTT classification (Mayo/AJCC), multimodal imaging, patient optimization, and level-specific open surgical techniques—ranging from Satinsky clamping for Level 0–I thrombi to full piggyback liver mobilization with hepatic vascular exclusion for Level III disease. Contemporary perioperative mortality is <2% at high-volume centers (reported in single and multicenter retrospective series from high-volume institutions), with 5-year cancer-specific survival of approximately 50–60% in non-metastatic cases. Adjuvant pembrolizumab is now a standard of care following the KEYNOTE-564 trial. Neoadjuvant immune checkpoint inhibitor plus tyrosine kinase inhibitor combinations show promising VTT downstaging rates (44–100%), though their role remains investigational. Robotic-assisted thrombectomy demonstrates favorable perioperative outcomes for Level I–II thrombi at experienced centers. Conclusions: Open surgery remains the cornerstone of curative treatment for RCC with infradiaphragmatic VTT, requiring meticulous preoperative planning and multidisciplinary collaboration at high-volume centers. Integration of perioperative systemic therapies and robotic-assisted approaches holds promise for further improving outcomes in this challenging patient population. Full article

Traditional enzyme-induced carbonate precipitation (EICP) technology for brick crack rehabilitation is commonly plagued by solution clogging and low repair efficiency. To overcome these technical limitations, a novel centrifugal cementation method was proposed in this study, with its core innovation lying in decoupling the EICP reaction from the masonry reinforcement process. After the complete reaction of urease with the cementation solution, a high-concentration calcium carbonate colloid was extracted via centrifugation, which was then mixed with fine sand to prepare a repair mortar for direct injection into brick cracks. The experimental results, based on a single-factor design with a fixed soybean powder concentration (180 g/L, peak urease activity), showed that the maximum flexural strength of the repaired bricks reached 2.31 MPa, recovering as much as 122.9% of that of the cracked unrepaired bricks. Furthermore, the flexural strength of the repaired bricks exhibited a significant positive correlation with the calcium carbonate content (20–100%) and curing time (3–28 days). Phase analysis indicated that the repair mortar was primarily composed of calcite and quartz. The high shear force generated by centrifugation triggered explosive nucleation of calcium carbonate, and spherical calcite particles were formed through Ostwald ripening, exhibiting a distinct characteristic of decoupling between the spherical morphology and calcite crystal phase. The centrifugal cementation method proposed in this study achieves excellent short-term repair effects for masonry structures under laboratory conditions, thus providing a novel technical approach for the crack rehabilitation of masonry structures. Full article

This study examines the carbonation behavior and CO₂ storage potential of a Ca-rich alkali-activated binder produced entirely from industrial residues-ladle furnace slag (LFS), coal ash (CA), and cement kiln dust (CKD). The system was designed as a one-part alkali-activated material (AAM), with CKD acting as an internal activator, and subjected to ambient curing, water curing, and accelerated CO₂ curing at ambient pressure. Phase evolution, microstructural development, and pore-structure characteristics were investigated using X-ray diffraction, FTIR spectroscopy, DSC–TG analysis, scanning electron microscopy, and X-ray micro-computed tomography, together with measurements of density, water absorption, and compressive strength. Loss-on-ignition measurements combined with chemical analysis were further used to quantify CO₂ uptake and evaluate the degree of carbonation of the binder system. CO₂ curing fundamentally altered the reaction pathway of the binder, shifting it from hydration-dominated to carbonation-controlled phase evolution, leading to the decomposition of calcium-bearing hydrates and complete carbonation of non-hydraulic γ-belite with the formation of vaterite, aragonite, and calcite. These transformations induced pronounced microstructural densification, reflected in a near-doubling of compressive strength (>48 MPa), increased apparent density, reduced water absorption, and simplified pore-network topology. A preliminary carbon footprint assessment indicates that the production of 1 m³ of the developed LFS–CA–CKD concrete generates about 14.36 kg CO₂-eq, while the carbonation process enables significant CO₂ sequestration, resulting in a net negative carbon balance. The results demonstrate that controlled carbonation is an effective post-treatment strategy for waste-derived alkali-activated binders, enabling simultaneous performance enhancement and permanent CO₂ sequestration. Full article

This study addresses the challenges posed by weakly cemented strata in mine tunnels, where surrounding rock softens and deforms upon water exposure, which promotes the development of seepage pathways, and exhibits insufficient stability in bolt (cable) support systems. This study conducts laboratory grouting tests using silica sol on typical weakly cemented sandstone from Xinjiang mining areas. The mineral composition and pore structure were characterized using XRD, SEM, and mercury porosimetry. The injectable mixing ratio parameters for silica sol and the catalyst were determined through viscosity-time evolution tests. Grouting was performed using a custom-built constant-pressure grouting apparatus. After curing, unconfined compressive strength (UCS) and porosity-permeability tests were conducted to evaluate the micro-mechanism of grouting effects on the mechanical and permeability properties of weakly cemented sandstone. The results indicate: (1) The sandstone exhibits a high clay mineral content of 39.8%, dominated by illite. Its pores are primarily small-scale (10–100 nm), accounting for 79.31% of the total pore volume. This scale matches that of silica sol nanoparticles (approximately 9–20 nm), facilitating slurry penetration into micro-pores; (2) microscopic analyses reveal that silica sol effectively reconstructs pore structures through permeation filling and surface coating. Compared to KCl-induced gelation (with approximately 8% gel coverage), NaCl-induced gelation forms a more continuous gel film with more complete pore filling, achieving coverage of around 22%. Furthermore, the larger surface area of the gel aggregates indicates a more thorough filling of micro- and nano-pores, effectively enhancing rock mass compactness. (3) Permeability decreased from 6.91 mD to 3.55 mD, a reduction of 48.6%, while porosity decreased from 16.94% to 13.55%, showing a phased reduction during the grouting process; (4) following pressure grouting stabilization, the uniaxial compressive strength of sandstone increased appropriately by approximately 7–14%, while the elastic modulus rose by about 18–28%. The failure mechanism shifted from shear brittleness to a shear-tension composite state, with enhanced post-peak bearing capacity. These findings provide support for optimizing silica sol grouting parameters in weakly cemented strata tunnels and for the synergistic reinforcement of rock mass permeability and strength. Full article

The transition to sustainable thermosetting resins is frequently hindered by the trade-off between high bio-based content and processability. This study reports a novel strategy in developing a highly bio-based, styrene-free unsaturated polyester resin (UPR) by leveraging maltodextrin-derived mixed esters dissolved in dimethyl itaconate (DMI). Unlike conventional polysaccharide-based systems that suffer from extreme viscosity, our functionalized prepolymer–DMI system achieves a low-viscosity curing solution without requiring petroleum-derived diluents such as styrene. Fourier-transform infrared spectroscopy confirmed the formation of a robust crosslinked network via the complete consumption of C=C bonds. Consequently, the cured resin exhibits exceptional thermal and mechanical performance, outperforming many existing bio-based analogs: a glass transition temperature (T_g) reaching 141 °C, a decomposition onset near 250 °C, and superior dimensional stability with a linear thermal expansion coefficient as low as 77 ppm/°C. Demonstrating a fully renewable, easy-to-process formulation with a flexural strength of 44 MPa, this work provides a design template for the next generation of high-performance, eco-friendly industrial thermosets. Full article

The long-term durability of hydraulic concrete infrastructure is severely compromised by water penetration, carbonation, and chloride ion erosion, necessitating the development of high-performance protective coatings. This study designed two polyaspartic ester polyurea coatings, PAE-PTMEG and PAE-PPG, derived from isocyanate prepolymers with polytetramethylene ether glycol (PTMEG) and polypropylene glycol (PPG) soft segments, respectively. The results demonstrated that the PTMEG-based prepolymer exhibited higher reactivity, leading to shorter curing times. The resulting PAE-PTMEG coating showed outstanding mechanical properties (tensile strength: 43.8 Mpa; elongation: 646.1%) and excellent water resistance (<1% absorption), attributable to its well-defined microphase-separated structure. When formulated into a practical paint (PAE-C), it surpassed mechanical standards for waterproofing and demonstrated exceptional resistance to chloride ion penetration (1.3 × 10⁻⁴ mg·cm⁻²·d⁻¹), complete carbonation resistance, and high frost resistance (200 cycles). This work confirms that tailoring the soft segment structure is a crucial strategy for developing durable polyurea coatings, with PAE-PTMEG showing significant potential for protecting critical water conservancy infrastructure. Full article

Tyrosine kinase inhibitors (TKIs) added to chemotherapy have improved outcomes of adult patients with Philadelphia-positive B-cell acute lymphoblastic leukemia (Ph+ B-ALL). These improvements initially led to a larger proportion of patients realizing allogeneic stem cell transplantation (alloSCT), long considered essential for cure, but there has been a re-evaluation of alloSCT. At Princess Margaret Hospital (PM), adult patients with Ph+ B-ALL have been treated with a pediatric-inspired chemotherapy protocol with mostly imatinib. In the last two decades, we have witnessed many iterative changes in our approach. Here, we examine the outcomes of all Ph+ B-ALL patients treated at our institution from 2001 to 2019. During this time, there were two major protocol changes—omission of asparaginase in 2009 and discontinuation of routine referral for first complete remission (CR1) alloSCT from the early 2010s. Median follow-up was 41.13 months (range, 0.46–228.79). In total, 141 patients (91.56%) achieved CR1. Patient outcomes improved iteratively, with the best results seen in the final (2016–2019) cohort: no asparaginase, no routine alloSCT referral in CR1; 4-year overall survival (OS) and relapse-free survival (RFS) were 87.0% and 69.3%, respectively. The long-term OS in this patient group retained statistical significance in the multivariable analysis (p = 0.0176) when BCR::ABL1 molecular measurable residual disease (MRD) was considered. Full article

Direct-acting antiviral therapies can cure most people with hepatitis C virus (HCV) infection with little need for testing or monitoring. A major challenge to eliminating HCV is ensuring patients complete all steps of care, including confirmation of cure. We assessed the concordance of sustained virologic response (SVR) at 4 weeks (SVR4) and 12 weeks (SVR12) post-treatment to evaluate the viability of SVR4 as a predictor of cure in patients treated with sofosbuvir (SOF)/velpatasvir (VEL). We conducted a retrospective analysis of patients from the Phase 3 ASTRAL-1, -2, and -3 programs and a historical cohort from the Louisiana Department of Health Sexually Transmitted Infection (STI)/HIV/Hepatitis Program claims database. Concordance analyses were performed for patients with both SVR4 and SVR12 data. The concordance analysis in the ASTRAL studies included 1015 patients; 1005 and 1002 achieved SVR4 and SVR12, respectively. Among SVR4 achievers, 3 failed to maintain SVR12, while all (10/10) patients who did not achieve SVR4 also failed SVR12. In the real-world cohort, 479/509 (94%) patients achieved SVR4 and 485/509 (95%) achieved SVR12. Of those with SVR4, 7 failed SVR12; 17 of 30 patients who did not achieve SVR4 also failed SVR12. High concordance between SVR4 and SVR12 was observed in both ASTRAL and the real-world dataset, supporting the use of SVR4 as a predictor of long-term SVR in patients with HCV infection treated with SOF/VEL. Streamlining cure confirmation by shifting SVR determination from week 12 to week 4 post-treatment may reduce patient loss to follow-up. Full article

Background: Congenital toxoplasmosis remains a significant cause of fetal morbidity worldwide. This case–control study aimed to identify sociodemographic, dietary, and behavioral factors associated with Toxoplasma gondii infection during pregnancy in Italy by comparing infected women with seronegative controls, and to evaluate modifiable risk behaviors and treatment-related outcomes among affected patients. Methods: This case–control study included 201 pregnant women (100 with T. gondii infection and 101 seronegative controls). Participants completed a structured questionnaire on sociodemographic factors, diet, environmental exposures, and preventive behaviors. Clinical data were collected for infected women and analyzed using SPSS v27.0. Results: Sociodemographic and obstetric characteristics did not differ between groups. Infected women were more likely to live in rural areas (p < 0.001), have a lower educational level (p = 0.009), consume unpasteurized dairy products and cured meats (p < 0.05), purchase food from farmers or butchers (p = 0.01), and do not check food preparation practices when eating outside the home. High-risk animal-related behaviors were also more common among cases (p < 0.001). Despite similar baseline awareness, adherence to preventive measures was lower among cases; most infections were diagnosed in the first trimester and treated with spiramycin with good tolerability. Conclusions: Maternal toxoplasmosis is mainly associated with modifiable behavioral and environmental factors, underscoring the need for targeted, preconception counseling to reduce the risk of congenital infection. Full article

This study evaluated the effects of different provisional luting cement removal methods on the shear bond strength (SBS) of resin cement to dentin following immediate dentin sealing (IDS) performed with two adhesive systems. A total of 168 extracted, caries-free human third molars were used, of which 144 were allocated for SBS testing and 24 for scanning electron microscopy (SEM) analysis. Specimens were assigned according to the IDS protocol (no IDS, IDS with OptiBond FL, or IDS with G2-Bond), followed by provisional cementation using an eugenol-free temporary cement. Contaminated surfaces were subsequently cleaned with a hand scaler, aluminum oxide (Al₂O₃) air abrasion, or Katana Cleaner prior to final bonding with a dual-cure resin cement. SBS was measured after 24 h of water storage, and surface morphology was evaluated by SEM at 2500× magnification. IDS significantly increased SBS under uncontaminated conditions, with G2-Bond-based IDS exhibiting higher bond strength values than specimens without IDS. However, provisional cement contamination significantly reduced SBS regardless of the cleaning method applied, and none of the tested protocols fully restored the bond strength observed in uncontaminated IDS-treated dentin. SEM analysis revealed residual cement remnants and surface alterations after cleaning, even in specimens that appeared macroscopically clean. Within the limitations of this in vitro study, IDS enhances resin–dentin bonding when contamination is avoided; however, current mechanical and chemical cleaning methods are insufficient to completely recover bond strength compromised by provisional cement contamination, highlighting the importance of preventing contamination and preserving IDS layer integrity during indirect restorative procedures. Full article

Menin inhibitors are the first targeted therapies for KMT2A-rearranged and NPM1-mutated acute leukemias, addressing a significant unmet need in these high-risk subtypes. Revumenib received approval in 2024–2025 for relapsed or refractory KMT2A-rearranged acute leukemia and NPM1-mutated AML. The AUG-MENT-101 trial reported a 23% composite complete remission rate in heavily pretreated patients, with 61% of responders achieving MRD negativity. Several menin inhibitors, including ziftomenib, bleximenib, and enzomenib, are in clinical development. They demonstrate similar efficacy, but their safety profiles differ, especially regarding QTc prolongation and coverage of resistance mutations. Combination therapies with azacitidine and venetoclax or intensive chemotherapy have achieved high response rates in newly diagnosed patients, supporting their potential use in frontline treatment. Acquired resistance, often due to MEN1 mutations at the drug-binding interface, occurs in about 40% of cases. Distinct resistance patterns among menin inhibitors suggest the possibility of sequential therapy. Approximately 30–40% of responders in relapsed or refractory trials proceeded to allogeneic transplantation, which remains a key pathway to potential cure. This review examines the molecular mechanisms of the menin-KMT2A interaction, and summarizes clinical trial data on the efficacy and safety of menin inhibitors as monotherapy and in combination. Full article