Search Results (8,166)

The introduction of a novel replaceable plastic hinge technology aims to enhance the performance of precast reinforced concrete (PRC) frames, particularly in seismically vulnerable areas where substandard structural systems are prevalent. This artificially controllable plastic hinge (ACPH) mechanism effectively localizes inelastic deformations to a detachable steel subassembly, thereby maintaining the integrity of the primary structural components. A numerical analysis was carried out on four distinct PRC frame configurations that utilized concrete and steel of inferior quality relative to contemporary standards. The frames underwent testing under a segment of the Mw 7.7 Kahramanmaraş ground motion, revealing that connections utilizing the ACPH not only reduce peak base shear but also mitigate cracking at beam–column interfaces, directing plastic strains towards replaceable fuse elements. The implementation of the ACPH also facilitates extended structural periods and localized plastic hinging, which serves to limit damage to essential members while expediting post-earthquake repairs. Comparative validation through prior subassembly tests confirms that this hinge exhibits a strong hysteretic response and ductile performance, surpassing traditional wet-joint connections in the context of substandard PRC frames. Overall, these results underscore the potential of standardized hinge modules in enhancing seismic resilience and supporting swift, economical rehabilitation of critical infrastructure. Thus, this proposed technology effectively tackles persistent issues related to low-strength materials in precast structures, presenting a practical approach to improving earthquake resilience and minimizing repair time and costs. Full article

A detailed characterization of evapotranspiration (ET) patterns is of paramount importance for optimizing irrigation scheduling and enhancing water-use efficiency in the North China Plain. To delve into this, a two-season study was conducted at the National Experimental Station for Precise Agriculture in Beijing. Using 12 weighing lysimeters, the study compared two summer maize varieties with contrasting canopy sizes: Jingke 968 (JK), characterized by a large canopy, and CF 1002 (CF), with a small canopy. The comprehensive analysis yielded the following significant findings: (1) The daily average ET rates exhibited consistent trends across cultivars, yet with notable disparities in magnitude. JK consistently demonstrated higher water consumption throughout the growth seasons. In the first season, at the V13–R1 stage, the peak daily ET of JK and CF reached 5.91 mm/day and 5.52 mm/day, respectively. In the second season, during the R1–R3 stage, these values were 5.21 mm/day for JK and 5.22 mm/day for CF, highlighting the nuanced differences in water use between the varieties under varying growth conditions. (2) Regardless of canopy size, the hourly ET fluctuations across different growth stages followed similar temporal patterns. However, the most striking inter-varietal differences in ET emerged during the R1–R3 reproductive stages, when both cultivars had achieved peak canopy development (leaf area index, LAI > 4.5). Notably, the ET differences between JK and CF adhered to a characteristic diurnal “increase–decrease” pattern. These differences peaked during mid-morning (09:00–11:00) and early afternoon (13:00–15:00), while minimal divergence was observed at solar noon. This pattern suggests complex interactions between canopy structure, microclimate, and plant physiological processes that govern water loss over the course of a day. (3) Analysis of the pooled data pinpointed two critical time periods that significantly contributed to the cumulative ET differences between the varieties. The first period was from 12:00–17:00 during the R1–R3 (anthesis) stage, and the second was from 08:00–16:00 during the R3–R5 (grain filling) stage. JK maintained significantly higher transpiration rates (Tr) compared to CF, especially during the morning hours (09:00–12:00). On average, the Tr of JK exceeded that of CF by 5.3% during the pre-anthesis stage and by 16.0% during the post-anthesis stage. These observed Tr differentials strongly indicate that canopy architecture plays a pivotal role in modulating stomatal regulation patterns. Maize varieties with large canopies, such as JK, demonstrated enhanced morning photosynthetic activity, which likely contributed to increased transpiration. At the same time, both varieties seemed to employ similar midday water conservation strategies, possibly as an adaptive response to environmental stress. In summary, this study has comprehensively elucidated the intricate relationship between the leaf area index and the evapotranspiration of summer maize across multiple timescales, encompassing periodic, daily, and hourly variations. The findings provide invaluable data-driven insights that can underpin the development of precise and quantitative irrigation strategies, ultimately promoting sustainable and efficient maize production in the North China Plain. Full article

The vertebral arteries supply blood to the upper spinal cord, brainstem, cerebellum, and posterior part of the brain. These arteries are susceptible to deformation from external factors such as muscular, ligamentous, or bony structures, and any interruption of blood flow may result in vertebrobasilar insufficiency. Among the osseous variants of the cervical spine with potential pathological significance, variations in the number, shape, and size of the foramen transversarium, as well as the presence of bony bridges in the first cervical vertebra, may suggest a predisposition to vertebrobasilar insufficiency. A skeletal sample from the post-Classical cemetery of Corfinio (12th–15th centuries CE; L’Aquila, Italy) was examined. Regarding the morphology of the foramen transversarium, shape variations were identified in 32 of the 108 vertebrae analysed (a prevalence of 29.6%). Particularly noteworthy are three findings in the atlas: (i) a high prevalence of foramen transversarium variants (35.7% for hypoplastic and double foramina), (ii) a coefficient of roundness consistent with a brachymorphic shape, and (iii) a high prevalence of bony bridges —especially ponticulus posticus (52.9%) and retrotransverse foramen (64.7%). All of these findings may indicate a predisposition to vertebrobasilar insufficiency in the individuals studied. It is hypothesised that external mechanical factors, such as carrying heavy loads on the head, neck, and shoulders due to work activities, along with possible genetic influences related to kinship, may have contributed to the high prevalence of these osseous variants. Full article

This study focuses on the investigation of the Tepehan landslide triggered by the 6 February 2023, Kahramanmaraş earthquake in Türkiye. The overall goal of this study is to understand the slope condition and simulate the failure considering pre- and post-event geometry. Topographic variations in the landslide area were analyzed using digital elevation models (DEMs) derived from the Sentinel-1 Synthetic Aperture Radar (SAR) satellite data and geospatial analysis. Slope stability analyses were conducted over a representative alignment, including assessments of soil structure, geological history, and field features. A limit equilibrium back-analysis was performed under both static and pseudo-static conditions, where an earthquake load coefficient was considered in the analyses. A total of five scenarios were evaluated to determine factors of safety (FoS) based on fully softened and residual strength parameters. The resulting critical slip surfaces from the simulations were compared with the geomorphometric analysis, necessitating the adjustment of the subsurface hard clay layer for residual conditions. The analyses revealed that the slope behaves as a delayed first-time landslide, with bedding planes acting as localized weak layers, reducing mobilized shear strength. This integrated remote sensing–geotechnical approach advances landslide hazard evaluation by enhancing the precision of slip surface identification and post-seismic slope behavior modeling, offering a valuable framework for similar post-disaster geohazard assessments. Full article

Single-crystal superalloys have attracted considerable interest in aero engine blade manufacture due to their superior mechanical properties, which maintain structural integrity at high temperatures. However, their anisotropic microstructure results in direction-dependent properties that pose a challenge for defect detection. This study proposes a methodology to determine the crystal orientation, which is subsequently used to improve the Total Focusing Method (TFM) by incorporating the refracted beam directivity. Firstly, simulations were performed using semi-analytical models (CIVA software 2023 SP4.1) to reproduce different grain orientations. The results were then post-processed to determine the grain orientation. Finally, the TFM was adapted to take into account not only the velocity variations due to orientation but also the directivity of the ultrasonic beam based only on slowness curves. The implementation of this methodology has improved the defect detection capability, optimizing the defect positioning by up to 61% and increasing the signal-to-noise ratio by up to 5 dB. This study demonstrates the effectiveness of an adapted inspection procedure for single crystals. Full article

(1) Background: Adolescents living with HIV (ALHIVs) experience significant challenges in adhering to treatment and remaining engaged in care as they transition from pediatric to adult HIV care programs. The aim of this qualitative evidence synthesis (QES) was to review qualitative studies that describe how ALHIVs experience transition practices in low- and middle-income countries. (2) Methods: The following databases were searched: PubMed, Wiley Library Online, EbscoHost (PsychARTICLES, MEDLINE, Scopus, CINAHL), the WHO database, Google Scholar, and reference mining of the included studies. The inclusion criteria were as follows: ALHIV 10–19 years old, interventions on the transition period or studies describing transition practices, published between 2012 and 2023, conducted in low- and middle-income countries, English language, and qualitative and mixed-method studies. This review adheres to the PRISMA guidelines. CASP and MMAT were used for methodological quality assessment, and GRADE CERQual was used for the confidence in review findings. (3) Results: Seven articles were included in the final review. The five overarching themes described: (1) transition readiness during the pre-transition phase; (2) structural (health systems) barriers and treatment literacy as challenges during the transition period; and (3) provided accounts of successful post-transition experiences and recommendations for improving the transition process (when these were not experienced as positive), while also describing the individual and collective contexts in which transition took place, as they outlined (4) individual (psychological) barriers and the facilitative role that (5) a supportive environment played in the outcome of the transition process. There was a high level of confidence in transition readiness, while the other themes were assessed as having moderate confidence due to methodological limitations and minor concerns about adequacy or relevance. (4) Conclusions: There is a dearth of qualitative studies on the transition experiences of ALHIVs and on how the transition process impacts adherence, retention in care, and mental well-being. We recommend the development of interventions in the form of a guided transition protocol to improve the transition experiences of ALHIVs. Full article

Background/Objectives: The inadequate management of postsurgical pain represents a major clinical issue, often leading to suboptimal outcomes in the immediate postoperative period and an increased risk of developing chronic postsurgical pain. The present study aimed to examine the relationship between postsurgical pain, mood, and the use of prescribed analgesics after total knee arthroplasty (TKA). Methods: This prospective observational explorative study enrolled 28 patients scheduled for TKA between February 2018 and March 2019. Using a digital experience sampling method (ESM) tool that included questions on pain, analgesic use, and both positive and negative effects, patients reported their current status up to ten times daily. The questions were administered over five days following postoperative discharge. Data analysis was performed using descriptive statistics and multilevel regression, accounting for the hierarchical structure of the data. Results: On 85.5% of the days post-discharge, the patients did not adhere to the prescribed acetaminophen regimen. Multilevel analyses revealed that the groups who overused or underused acetaminophen reported significantly heightened levels of pain. NSAIDs were generally underused. Post-discharge opioid use decreased over time, with no evidence of abuse. Overall, the non-adherent group reported lower mood levels and higher pain scores than the adherent group. Conclusions: Most patients did not adhere to the prescribed analgesics despite experiencing pain. Therefore, clinical interventions should prioritize identifying patient subtypes to tailor analgesic use effectively. This approach will facilitate the development and improvement of personalized acute postsurgical pain treatment protocols, ensuring more precise and effective pain management strategies for patients. Full article

The composite primary structures of railway vehicles endure not only mechanical loads including tension, compression, bending, and torsion, but also external impacts, such as by the crushed stone in ballast. In the present study, the low-velocity impact response of preloaded hybrid composite laminates with different thicknesses is examined using a finite element method based on a progressive damage model. The hybrid plate consists of carbon fiber-reinforced unidirectional and woven prepregs. The progressive damage model, based on the 3D Hashin model, is validated by experiments on hybrid laminate, and further compared with the post-impact appearance obtained from CT scans. Preloading, considered to be tensile, compressive, or shear, corresponds to different positions in a bending beam with flanges and a web. Finally, the effects of impact energy, preloading, thickness, and impact angle on the dynamic response are analyzed, with an emphasis on new results and failure mechanism analysis comparing the influence of preloads under a given impact energy and different thicknesses. Full article

The COVID-19 pandemic disrupted tuberculosis (TB) control, increasing mortality and potentially worsening disparities. This study aimed to analyze the temporal trends of TB mortality in Brazil and to trace the COVID-19 pandemic’s effect using a Bayesian approach, focusing on nationwide data. An ecological study of TB deaths recorded in the Mortality Information System (SIM) from 2012 to 2022 was conducted. Trends and percentage changes in the mortality were estimated. A Bayesian Structural Time Series model combined with an Autoregressive Integrated Moving Average model was used to assess the pandemic’s effect on TB. A total of 51,809 TB deaths were identified, with a mortality rate of 2.27 per 100,000. Higher rates were found among the elderly (6.86), indigenous populations (5.58), and black individuals (4.21). The Bayesian model estimated a 9.9% (CI 8.8–11%) increase in TB mortality due to COVID-19. The Midwest region showed the highest increase (30%, 25–35%). Females experienced a greater post-pandemic monthly increase (2.80%) in mortality than males (0.72%). The Bayesian analysis revealed a significant rise in TB mortality during the COVID-19 pandemic, with notable disparities affecting females, the elderly, the indigenous, and the black populations. These findings highlight the pandemic’s long-term impact on TB and stress the need for equity-focused, data-driven public health responses in Brazil. Full article

This study explores how rural tourism destinations in the Eastern Carpathians of Romania have recovered in the aftermath of the COVID-19 pandemic. Using data from 2016–2019 and 2021–2023, five core indicators—tourist arrivals, overnight stays, accommodation capacity, occupancy rates, and active units—were analyzed at the local level. Based on these indicators, a cluster analysis was conducted for us to identify groups of communes with similar tourism performance profiles. After clustering, composite indicators were calculated to track how each group evolved over time. The findings show that recovery has not been uniform: while some destinations bounced back or even improved, others continue to face structural challenges. These results suggest that local infrastructure, destination type, and governance capacity all play a role in shaping recovery paths. The paper offers a spatial overview of rural tourism dynamics and highlights the value of using data-driven tools for understanding uneven development in post-crisis contexts. Full article

Poly (methyl methacrylate) (PMMA) bone cement is widely used in percutaneous vertebroplasty to stabilize osteoporotic vertebral compression fractures. However, its clinical application is limited by its high compressive modulus, risk of thermal necrosis, and poor bone integration, unlike conventional PMMA formulations used in vertebrae or joint arthroplasty, which can reach polymerization temperatures exceeding 100 °C. Spine-specific PMMA is formulated to cure at a reduced polymerization temperature, thereby minimizing the rise in core temperature during the setting process. Consistent with our hypothesis, this moderate thermal output induces localized thermal injury that triggers osteogenic responses and extracellular matrix production, thereby enhancing osteoblast activity in the surrounding bone. This study aimed to evaluate bone remodeling following spine-specific PMMA injection in an osteoporotic Sprague-Dawley (SD) rat model. Twenty-four osteoporotic female SD rats were randomly assigned to three groups: Control (untreated), OVX + spine-specific PMMA (OVX + PMMA), and OVX (OVX + Defect). Bone regeneration was assessed using dual-energy X-ray absorptiometry (DXA), micro-computed tomography (Micro-CT), quantitative PCR (qPCR), immunohistochemistry (IHC), and Western blotting. At 12 weeks post-injection, the OVX + PMMA group exhibited significantly greater bone regeneration than the OVX group. Micro-CT analysis demonstrated a marked increase in trabecular thickness in the PMMA-treated group. Notably, bone formation was more pronounced in regions surrounding the cement compared to adjacent untreated areas. This suggests that spine-specific PMMA promotes osteogenesis via localized thermal necrosis and subsequent osteoblast recruitment. These findings highlight the dual role of spine-specific PMMA in both structural stabilization and biologically driven bone regeneration. Further research is warranted to optimize its clinical applications while minimizing potential adverse effects. Full article

In recent years, climate change has attracted the attention of the scientific community. These changes are attributed to human action, which is responsible for the emission of polluting gases, mainly through the burning of fossil fuels, deforestation, and industrial processes that are responsible for the greenhouse effect. Post-combustion CO₂ capture using solid adsorbents is a technology that is currently gaining prominence as an alternative and viable form of capture to other industrial processes used. Zeolites are adsorbents capable of capturing CO₂ selectively due to their properties such as textural properties, high surface area, and active sites. In this context, this work developed materials with a zeolite structure with an alternative low-cost silica source from beach sand, called MPI silica, to make the process eco-friendly. Crystallization time studies were carried out for materials containing MFI-type zeolites with MPI silica with a time of 15 h (ZM 15 h) and 3 days (SM 3 d), with relative crystallinities of 92.90% and 111.90%, respectively. The synthesized materials were characterized by several techniques such as X-ray diffraction (XRD), X-ray fluorescence (XRF), the textural analysis of N₂ adsorption/desorption isotherms, absorption spectroscopy in the infrared region with Fourier transform (FTIR), scanning electron microscopy (SEM), and thermal analysis. The evaluation of the experimental adsorption isotherms showed that the best results were for the zeolites synthesized in the basic medium, namely ZMP 3 d, ZM 10.5 h, and ZM 15 h, with capacities of 3.72, 3.10, and 3.22 mmol/g of CO₂, respectively, and in the hydrofluoric medium, namely SP 9 d, SM 3 d, and SM 6 d, with capacities of 3.94, 3.78, and 3.60 mmol/g of CO₂, respectively. The evaluation of the mathematical models indicated that the zeolites in the basic medium best fitted the Freündlich model, namely ZMP 3 d, ZM 10.5 h, and ZM 15 h, with capacities of 2.56, 1.68, and 1.87 mmol/g of CO₂, respectively. The zeolites in the hydrofluoric medium are adjusted to the Langmuir model (SP 9 d and SM 3 d) and Temkin model (SM 6 d), with capacities of 3.79, 2.23, and 2.11 mmol/g of CO₂, respectively. Full article

Myocardial infarction (MI) is a leading cause of morbidity worldwide, resulting from ischemic damage and necrosis to cardiomyocytes. While the standard treatment regimen for MI can be successful in restoring coronary perfusion, it typically does not resolve myocardial damage, which can leave patients particularly vulnerable to complications such as heart failure or electrical conduction abnormalities. Stem cell therapies offer a promising novel approach aimed at restoring cardiac function and decreasing the incidence of functional complications after an MI. This review used a literature search to evaluate the current landscape of stem cell therapy for post-MI recovery and focuses on the stem cell candidates for MI recovery therapy, delivery methods of such treatment, and their effectiveness. Both preclinical and clinical trials have demonstrated the safety of stem cells, but have struggled with limited cell retention, inconsistent efficacy, and survival. Mechanisms are employed by stem cells to promote regeneration, such as paracrine signaling, angiogenesis, and structural remodeling, in addition to the various stem cell delivery methods, including intracoronary infusion, direct myocardial injection, and intravenous administration. Furthermore, some strategies to combat past challenges in this field are discussed; for instance, extracellular vesicles, bioengineered patches, hydrogels, gene editing, and bioprinting. This article will provide a framework for future research in stem cell therapies and highlight the current progress in the field. Full article

Germinated brown rice (GBR), rich in high starch content and bioactive compounds, has excellent gel-forming properties, rendering it highly promising for applications in food 3D printing, a cutting-edge personalized manufacturing technology. This study systematically investigates the effects of different concentrations of konjac glucomannan (KGM) and curdlan (CD) blends on the 3D printing performance and physicochemical properties of GBR gel. The results indicated that the appropriate addition of KGM/CD blends significantly enhances the printing accuracy and shape retention of GBR gel. Specifically, under the KGM to CD ratio of 3:1 (KC3) formulation obtained by combining 2.25% KGM and 0.75% CD, the printing accuracy was highest with a minimized error of 4.97 ± 0.45%, and optimal structural stability was maintained within 5 h post-printing. Rheological measurements revealed that the flow behavior index (n) of the KC3 system was 0.049 ± 0.014, indicating superior flowability and significantly improved overall rheological stability. Additionally, the blend system not only increased the hardness and gel elasticity of the GBR gel but also significantly enhanced its cohesiveness and adhesiveness, reaching the highest values of 0.323 ± 0.02 and −217.488 ± 22.499, respectively, in the KC3 formulation. Further thermal analysis, low-field nuclear magnetic resonance analysis, along with Fourier-transform infrared spectroscopy and scanning electron microscopy observations, collectively demonstrated that the KGM/CD blend effectively reinforced the stability of the GBR gel network structure. These findings provide theoretical support for optimizing GBR applications in food 3D printing. Full article

Background/Objective: Changes in limb volume affect prosthetic socket fit and limb health, which in turn affects the comfort, stability, and usability of a prosthesis. The objective of this research was to identify and evaluate residual limb fluid volume metrics that could be used to identify the need for a prosthetic socket modification or replacement. Methods: A prospective observational study was conducted with transtibial prosthesis users undergoing socket modification or replacement. Participants performed a morning and afternoon 20 min structured activity protocol and self-reported their average socket comfort and other health outcomes before and after their socket was modified or replaced. Limb fluid volume changes across the protocol were recorded using bioimpedance analysis. Results: Anterior region residual limb fluid volume loss was low when the socket comfort score was high. Participants with ESCS_ave increases of ≥2 points pre- to post-modification experienced less limb fluid volume loss post-modification minus pre-modification (mean +0.6%) compared to participants with ESCS_ave increases of <2 points (mean −0.9%) (p = 0.0002). Conclusions: The percentage of fluid volume in the anterior limb may be a useful quantitative metric to explore for the application of bioimpedance monitoring in clinical care, helping to identify when sufficient change has occurred such that a new socket is warranted. Full article