Search Results (129)

To address the issues of low permeability, clogging susceptibility, and insufficient circumferential bearing capacity of traditional drainage blind pipes behind tunnel linings in water-rich areas, this study proposes a novel curved-mesh circumferential drainage blind pipe specifically designed for such environments. First, through engineering surveys and comparative analysis, the limitations and application demands of conventional circumferential annular drainage blind pipes in highway tunnels were identified. Based on this, the key parameters of the new blind pipe—including material, wall thickness, and aperture size—were determined. Laboratory tests were then conducted to evaluate the performance of the newly developed pipe. Subsequently, the pipe was applied in a real-world tunnel project, where a construction process and an in-service blockage inspection method for circumferential drainage pipes were proposed. Field application results indicate that, compared to commonly used FH50 soft permeable pipes and F100 semi-split spring pipes, the novel curved-mesh drainage blind pipe exhibits superior circumferential load-bearing capacity, anti-clogging performance, and deformation resistance. The proposed structure provides a total permeable area exceeding 17,500 mm², three to four times larger than that of conventional drainage pipes, effectively meeting the drainage requirements behind tunnel linings in high-water-content zones. The use of four-way connectors enhanced integration with other drainage systems, and inspection of the internal conditions confirmed that the pipe remained free of clogging and deformation. Furthermore, the curved-mesh design offers better conformity with the primary support and demonstrates stronger adaptability to complex installation conditions. Full article

In this work, a finite element modelling methodology is presented for the prediction of the bending behaviour of a glass fibre-reinforced elastomer composite with embedded shape memory alloy (SMA) wire actuators. Three configurations of a multi-layered composite with differences in structural stiffness and thickness are experimentally and numerically analysed. The bending experiments are realised by Joule heating of the SMA, resulting in deflection angles of up to 58 deg. It is shown that a local degradation in the structural stiffness in the form of a hinge significantly increases the amount of deflection. Modelling is fully elaborated in the finite element software ANSYS, based on material characterisation experiments of the composite and SMA materials. The thermomechanical material behaviour of the SMA is modelled via the Souza–Auricchio model, based on differential scanning calorimetry (DSC) and isothermal tensile experiments. The methodology allows for the consideration of an initial pre-stretch for straight-line positioned SMA wires and an evaluation of their phase transformation state during activation. The results show a good agreement of the bending angle for all configurations at the activation temperature of 120 °C reached in the experiments. The presented methodology enables an efficient design and evaluation process for soft robot structures with embedded SMA actuator wires. Full article

Background and Objectives: The objective of this review is to evaluate the current evidence regarding hormone treatments for both premenopausal and postmenopausal women with early-stage hormone receptor (HR) positive breast cancer. Materials and Methods: An in-depth exploration of the existing literature was conducted, with landmark clinical trials such as TEXT, SOFT, ATLAS, and aTTom serving as primary references. Results: Through an extensive review of the literature, our findings indicate that for premenopausal women with HR-positive, HER2-negative BC with a low risk of recurrence, standard 5-year monotherapy with tamoxifen represents the optimal therapeutic management, given its favorable clinical outcomes and lower associated toxicity. In contrast, for premenopausal women with an intermediate to high risk of recurrence with the same tumor characteristics, the most effective approach stated in the literature is a combination of ovarian suppression therapy (chemical/surgical) and an aromatase inhibitor/selective estrogen receptor modulator (tamoxifen), with a possible extension of the standard therapeutic period. In postmenopausal patients with HR-positive, HER2-negative breast cancer with a low recurrence risk, the first line of treatment is usually a standard 5-year period of treatment with aromatase inhibitors (AIs)(letrozole, anastrozole, or exemestane). On the other hand, in postmenopausal women with an intermediate to high risk, combination therapy might be needed, as well as an extension of the standard therapeutic time. Conclusions: Treatment consensus depends on pre- vs. postmenopausal status and recurrence risk. Full article

Background: Soft liners offer a cushioning effect that aids in the healing of inflamed mucosa and allocates the relevant load in the support area of prostheses, enhancing their fit and stability. This study looks at how strontium-infused phosphate bioactive glass affects a heat-cured acrylic-based soft liner, focusing on the surface hardness and the surface roughness of the material. Methods: One hundred soft liner specimens were produced, with fifty specimens being designated for surface hardness testing and fifty specimens for surface roughness testing. PBG*Sr was incorporated into the soft liner at the concentrations of 1 wt.%, 3 wt.%, 5 wt.%, and 7 wt.%. Surface hardness and surface roughness were evaluated with a digital durometer for Shore A hardness and a profilometer, respectively. Fourier transform infrared spectroscopy analysis and field emission scanning electron microscopy were employed. Results: The Shapiro–Wilk test demonstrated that the data adhered to a normal distribution, as the p-values were not statistically significant. Subsequently, for statistical analyses following the one-way ANOVA, Dunnett’s T3 post hoc test was employed for surface hardness, while Tukey’s post hoc test was used for surface roughness. The lowest hardness value was documented in the 7 wt.% subgroup (29.040 ± 0.070), followed by the 5 wt.% subgroup (30.97 ± 0.231), and the control (40.880 ± 0.473) had the highest hardness mean value. The 7 wt.% subgroup displayed the lowest value of Ra recorded, 0.489 ± 0.077 μm, while the control subgroup showed the highest, 1.994 ± 0.168 μm. FTIR analysis suggested that the domination of physical interactions according to the analyses with the FESEM led to improved surface morphology for the 7 wt.% PBG*Sr specimens. Conclusions: The 7 wt.% PBG*Sr specimens exhibited the lowest surface hardness, suitable for soft lining material, and improved the surface morphology of acrylic soft liners compared with the control and other concentrations. Full article

Due to the complexity of planning and constructing underground lines, construction challenges—such as close proximity and multi-line interactions—are increasingly being recognized, along with their associated safety hazards. The visual observation of tunnel deformation and changes in the surrounding strata is difficult. In this study, laboratory model experiments were conducted using a mixture of liquid paraffin, n-tridecane, and silica gel powder, combined in specific proportions to create a transparent material that simulates natural soft rock. The new tunnel was designed to simultaneously cross over and under two existing tunnels. The impact of the new tunnel on the existing tunnels was examined, with excavation length and soil layer thickness considered as the primary influencing factors. The results indicate that excavating the new tunnel causes settlement deformation in the tunnels above and heave deformation in the tunnels below. The magnitude of deformation increases as excavation progresses but decreases with the greater thickness of the soil interlayer. For an existing tunnel, variations in the thickness of the soil interlayer not only affect its own deformation but also disturb the tunnel on the opposite side. Therefore, to ensure safer and orderly urban tunnel construction and to address the “black box” effect, it is essential to study the deformation characteristics of existing tunnels and their surrounding rock during the construction of new tunnels. Full article

Restricted by the inherent low sensitivity of materials and complex integration technology, it is difficult for existing soft actuators (s-actuators) to simultaneously possess the advantages of flexibility, fast response, and simple manufacturing, which greatly limits their practical applications. Herein, a stretchable (ε = 200%) nanocomposite film capable of deformation and motion driven by near infrared light (NIR) was developed using multi-walled carbon nanotubes (MWCNTs) as the light absorption–photothermal conversion nanonetwork, and liquid crystal polymer (LCP) as an elastic matrix featured reversible phase transition. Furthermore, s-actuators with various deformation and motion modes have been realized employing MWCNT/LCP nanocomposite film. Based on the mechanism that photothermal-effect-regulated liquid crystal–isotropic phase transition in LCP can induce macroscopic deformation of nanocomposites, MWCNT/LCP s-actuators have completed a series of complex deformation and motion tasks such as opening the knot, “V”-shape reversible deformation (30 s per cycle), the “spring” rotating and unfolding, imitating a “caterpillar” walking in a straight line (the average speed is 13 s/mm), etc. This work provides an effective strategy for the intelligent development of s-actuators. Full article

Introduction: Elbow primary stability is guaranteed by the anatomical congruency between the humeral trochlea and the greater sigmoid notch (GSN). Elbow dislocation typically occurs in a semi-extended position, but computed tomography (CT) scans are typically acquired at 90° of elbow flexion, which may misleadingly suggest that the apex of the coronoid aligns with the trochlear center of rotation. This study aims to evaluate the anatomical features of the coronoid and GSN in a dislocated versus non-dislocated group, demonstrating that a more prominent coronoid process is more commonly observed in elbows without dislocation compared to those with dislocation. Materials and Methods: A total of 50 CT scans, equally divided between dislocated elbows and non-dislocated elbows, were analyzed, and the critical coronoid angle (CCA) was measured on a specific slice of the CT scan (level of evidence III). The CCA was calculated from two lines that arise in the center of the GSN, with the first one crossing the coronoid tip and the second parallel to the posterior olecranon cortex. Results: A significant difference in the CCA (p < 0.001) between the two groups was highlighted. In particular, it was found that 14/25 patients from the dislocated elbow group had a CCA below or equal to 27°, and all the non-dislocated subjects had a CCA ≥ 27°. These preliminary results suggest that a CCA ≤ 27° could be a threshold for requiring further imaging of soft tissues or closer follow-up. This may result from either a hypoplastic coronoid process or a decreased concavity of the GSN. Based on the CCA values, a logistic regression model (DAM model) was proposed to associate a coefficient of protection to the CCA, the angle of flexion during dislocation (FdD), and a parameter X, which is a factor that encompasses the contribution of soft tissues. Conclusions: A low CCA is statistically more frequent in dislocated elbows versus non-dislocated ones, creating a specific anatomical condition. The CCA should be carefully evaluated by elbow surgeons to guide patient-specific treatment. The DAM model can permit the stratification of patients eligible for further diagnostic analysis. Full article

Inductive power transfer (IPT) systems are transforming railway infrastructure by enabling efficient, wireless energy transmission for electric locomotives equipped with Li-ion batteries. This technology eliminates the need for overhead power lines and third rails, offering financial and operational advantages over conventional electric propulsion systems. Despite its potential, IPT deployment in rail applications faces significant challenges, including the fragility of materials (i.e., ferrite and Litz wires), thermal management during high-power transfers, and electromagnetic interference (EMI) on the transmitter side. This study discusses several factors affecting IPT efficiency and introduces magnetic concrete as a durable and cost-effective material solution for IPT systems. Magnetic concrete combines soft ferrite powder with water and coarse aggregates to enhance magnetic functionality while maintaining structural strength comparable to conventional concrete. Its durability and optimized magnetic properties promote consistent power transfer efficiency, making it a viable alternative to traditional ferrite cores. A comparative study has been performed on non-magnetic and magnetic concrete (with 33% ferrite powder) using both permeability tests and finite element analysis (FEA). The FEA includes both thermal and electromagnetic simulations using Ansys Maxwell (v.16), revealing that magnetic concrete can improve temperature management and EMI mitigation, and the findings underscore its potential to revolutionize IPT technology by overcoming the limitations of traditional materials and enhancing durability, cost-efficiency, and power transfer efficiency. By addressing the challenges of fragility, thermal management, and shielding of the unique coil topology design presented, this study lays the groundwork for improving IPT infrastructure in sustainable and efficient rail transport systems. Full article

Integrating soft components into denture design may significantly enhance the comfort of edentulous patients. Microorganisms, particularly Candida albicans, often colonize soft denture lining materials, which can release metabolic and toxic byproducts linked to the development of Denture-Induced Stomatitis. This study aimed to evaluate the effectiveness of antimicrobial agents incorporated into soft denture liners in inhibiting the adhesion and colonization of C. albicans. A systematic review was conducted through MEDLINE-Pubmed, EMBASE, and the Cochrane Central Register of Controlled Trials. A range of keywords was employed without applying a time filter to identify relevant literature. The review revealed many studies investigating various antimicrobial compounds added to different soft denture liner materials, all demonstrating the ability to inhibit the proliferation of C. albicans. All the antimicrobial agents examined exhibited a significant antifungal effect, with minimal to negligible impact on the physical properties of the denture liners. However, it was noted that the mechanical properties of the liners were modified in direct correlation to the concentration of the antimicrobial agents utilized. The successful incorporation of these agents into various soft denture liners has been documented, with nystatin being the primary pharmacological agent identified across multiple studies. While incorporating antibacterial agents was deemed successful, it is essential to note that the methodologies employed yielded varying effects on the overall performance of the soft-liner materials. Full article

Background and Objectives: Diagnostic imaging is essential for evaluating urinary tract disorders, offering critical insights into renal pathology. This review examines the strengths, limitations, and clinical applications of various imaging modalities, with a focus on pediatric populations. Materials and Methods: A narrative review was conducted, synthesizing current literature on ultrasound (US), computed tomography (CT), magnetic resonance imaging (MRI), nuclear medicine, and voiding cystourethrography (VCUG). Relevant studies were selected based on diagnostic accuracy, clinical utility, and safety considerations. Results: US is the preferred first-line imaging due to its safety, accessibility, and cost-effectiveness. CT excels in detecting renal calculi, trauma, and malignancies but is limited by radiation exposure. MRI offers superior soft tissue contrast without radiation but is costly and often requires sedation. Nuclear medicine evaluates renal function and scarring, while VCUG remains the gold standard for diagnosing vesicoureteral reflux and posterior urethral valves. Conclusions: Imaging modalities are vital for diagnosing and managing urinary tract disorders, with selection based on clinical needs, patient age, and safety. Ultrasound is the primary choice for its non-invasiveness and cost-effectiveness, while CT, MRI, nuclear medicine, and VCUG provide essential structural and functional insights. A balanced approach ensures accuracy while minimizing patient risk, especially in pediatrics. Full article

(1) Background and Objectives: Congenitally missing bilateral maxillary lateral incisors (CMBMLIs) present significant aesthetic, functional, and psychosocial challenges that require an orthodontic approach based on multidisciplinary consensus. The aim of this study was to evaluate the skeletal, dental, and soft tissue changes in patients with CMBMLIs treated with space opening and closure methods and to compare these changes with those in untreated individuals. (2) Materials and Methods: A total of 53 patients (mean age 16 ± 3.5 years) were included, and three groups were formed: the study groups, consisting of the space opening group (n = 18) and the space closure group (n = 17), and the control group (n = 18), which had ideal occlusion. A total of 14 angular and 13 linear measurements were performed on lateral cephalograms before (T0) and after (T1) treatment. Statistical significance was set at p < 0.05. (3) Results: Compared to the control group, significant post-treatment changes were more evident in dental measurements and less evident in skeletal and soft tissue measurements. A statistically significant increase in the U1/SN angle was observed in the space opening group compared to the space closure group. The U1/NA angle increased significantly in both study groups, with a greater increase in the space opening group. However, although the change in U1/NA angle was not significantly different between groups, the increase was greater in the space opening group. No significant differences were found between the control and study groups in the nasolabial angle, upper lip length and thickness, and the distance from the upper and lower lips to the E-line. (4) Conclusions: While space opening and closure methods had minimal effects on most skeletal and soft tissue parameters, the space opening method significantly altered the maxillary incisor position. Considering the waiting period for prosthetic restoration after space opening and potential alveolar bone limitations, space closure is recommended for CMBMLIs when feasible because it ensures a more predictable planned maxillary incisor position. Full article

Biopolymer hydrogel-based scaffold materials have received a lot of interest in tissue engineering and regenerative medicine because of their unique characteristics, which include biocompatibility, biodegradability, and the ability to replicate the natural extracellular matrix (ECM). These hydrogels are three-dimensional biopolymer networks that are highly hydrated and provide a supportive, wet environment conducive to cell growth, migration, and differentiation. They are especially useful in applications involving wound healing, cartilage, bone, and soft tissue regeneration. Natural biopolymers such as collagen, chitosan, hyaluronic acid, and alginate are frequently employed as the foundation for hydrogel fabrication, providing benefits such as low toxicity and improved cell adherence. Despite their potential, biopolymer hydrogel scaffolds have various difficulties that prevent broad clinical implementation. Key difficulties include the challenge of balancing mechanical strength and flexibility to meet the needs of various tissues, managing degradation rates to line up with tissue regeneration, and assuring large-scale manufacturing while retaining scaffold uniformity and quality. Furthermore, fostering appropriate vascularization and cell infiltration in larger tissues remains a significant challenge for optimal tissue integration and function. Future developments in biopolymer hydrogel-based scaffolds are likely to concentrate on addressing these obstacles. Strategies such as the creation of hybrid hydrogels that combine natural and synthetic materials, smart hydrogels with stimulus-responsive features, and 3D bioprinting technologies for accurate scaffold production show significant potential. Furthermore, integrating bioactive compounds and growth factors into hydrogel matrices to promote tissue regeneration is critical for enhancing therapeutic results. Full article

The colonizing of temporary soft lining materials in the oral cavity by yeast-like fungi, particularly Candida albicans, poses a significant risk of complications during prosthetic treatment. Various experimental materials incorporating antimicrobial additives, such as drugs, natural oils, and inorganic particles, have been tested. However, these components are not chemically bonded to a polymer network, making them prone to being easily released into the surrounding environment. This study aimed to evaluate experimental soft lining materials containing liquid components with 2-(methacryloyloxy)ethyl-2-decylhydroxyethylmethylammonium bromide, a monomethacrylate monomer with a quaternary ammonium group, added at concentrations of 8.54%, 8.75%, and 14.90% by weight. The adherence of Candida albicans, cytotoxicity, glass transition temperature (Tg), sorption (WS), solubility (WSL), Shore A hardness (SHA), tensile strength (TS), and tensile bond strength (TBS) were tested. Two tested materials did not show cytotoxicity for the 2-day undiluted extracts. The Candida albicans adhesions were reduced for two materials. The SHA values compared to the control were varied but all decreased with time. WS and WSL increased compared to the control. The TBS values were at an acceptable level. Full article

Introduction: Adolescent/young adult (AYA) patients with metastatic soft tissue sarcoma (STS) typically face a dismal prognosis. However, a subset of patients with incurable disease lives beyond two years. Due to the rarity of diagnoses and inherent heterogeneity within this population, a paucity of data exists regarding the experiences of AYAs with an indolent course (and how to best capture these experiences). With increasing biological insight and clinical experience, including the use of targeted or immune therapies, it is anticipated that more such patients will experience prolonged survival. Our pilot study aimed to describe the clinical characteristics and illness experiences of AYAs with incurable yet indolent metastatic STS who were living two years after their diagnoses. Our exploratory aim was to generate a conceptual framework that could subsequently be tested in a multi-center study with a larger cohort of patients. Materials and Methods: Patients with metastatic incurable STS, aged 15–39 years at diagnosis, and at least two years from diagnosis, were eligible. Patients were recruited over a two-year period at a quaternary children’s hospital with a comprehensive AYA oncology program. Participants completed a demographic form and PROMIS short form questionnaires for seven domains and answered an open-ended question. Responses to open-ended questions were coded independently by two authors and utilized to generate themes. Clinical variables were collected from medical records. Results: Five patients completed questionnaires. Mean age was 29.4 years (18.5–39.8 years) at diagnosis and 34 years (23.2–45.7 years) at study. Three patients were female; two were male; four were White; and one was Black/African American. Diagnoses included ASPSCR1::TFE3 alveolar soft part sarcoma; WWTR1::CAMTA1 epithelioid hemangioendothelioma; INI-1 deficient epithelioid sarcoma; EWSR1::NR4A3 extra-skeletal myxoid chondrosarcoma; and low-grade ARHGAP23::FER spindle cell malignancy, a novel fusion-driven sarcoma. Mean time since diagnosis was 4.5 years (2.6–6 years), and mean treatment duration was 4.2 years (1.5–6 years). On average, patients received 4.8 lines (range 2–8 lines) of antineoplastic therapy. All patients received at least one targeted therapy or immune checkpoint inhibitor. Patients reported increased fatigue and anxiety and decreased physical function compared to the standardized US reference population. Themes emerging from qualitative responses included managing physical symptoms, navigating feelings of guilt and inadequacy, self-reflection generating gratitude, and changing illness experiences over time. Conclusions: AYA patients living with incurable metastatic soft tissue sarcoma for more than two years were treated with multiple lines of antineoplastic therapy longitudinally. PROMIS data identified fatigue, anxiety, and decreased physical function within this population. Exploratory thematic analysis of qualitative responses generated concepts that could be further tested in an expanded cohort of patients. Full article

A novel piezoresistive cantilever microprobe (PCM) with an integrated electrothermal or piezoelectric actuator has been designed to replace current commercial PCMs, which require external actuators to perform contact-resonance imaging (CRI) of workpieces and avoid unwanted “forest of peaks” observed at large travel speed in the millimeter-per-second range. Initially, a PCM with integrated resistors for electrothermal actuation (ETA) was designed, built, and tested. Here, the ETA can be performed with a piezoresistive Wheatstone bridge, which converts mechanical strain into electrical signals by boron diffusion in order to simplify the production process. Moreover, a new substrate contact has been added in the new design for an AC voltage supply for the Wheatstone bridge to reduce parasitic signal influence via the EAM (Electromechanical Amplitude Modulation) in our homemade CRI system. Measurements on a bulk Al sample show the expected force dependence of the CR frequency. Meanwhile, fitting of the measured contact-resonance spectra was applied based on a Fano-type line shape to reveal the material-specific signature of a single harmonic resonator. However, noise is greatly increased with the bending mode and contact force increasing on viscoelastic samples. Then, to avoid unspecific peaks remaining in the spectra of soft samples, cantilevers with integrated piezoelectric actuators (PEAs) were designed. The numbers and positions of the actuators were optimized for specific CR vibration modes using analytical modeling of the cantilever bending based on the transfer-matrix method and Hertzian contact mechanics. To confirm the design of the PCM with a PEA, finite element analysis (FEA) of CR probing of a sample with a Young’s modulus of 10 GPa was performed. Close agreement was achieved by Fano-type line shape fitting of amplitude and phase of the first four vertical bending modes of the cantilever. As an important structure of the PCM with a PEA, the piezoresistive Wheatstone bridge had to have suitable doping parameters adapted to the boundary conditions of the manufacturing process of the newly designed PCM. Full article