Search Results (679)

This study employs a force element analysis to investigate vortex-induced vibrations (VIV) of three side-by-side circular cylinders at Reynolds number Re = 100, mass ratio m* = 10, spacing ratios S/D = 3–6, and reduced velocities Ur = 2–14. The lift and drag forces are decomposed into three physical components: volume vorticity force, surface vorticity force, and surface acceleration force. The present work systematically examines varying S/D and Ur effects on vibration amplitudes, frequencies, phase relationships, and transitions between distinct vortex-shedding patterns. By quantitative force decomposition, underlying physical mechanisms governing VIV in the triple-cylinder system are elucidated, including vortex dynamics, inter-cylinder interference, and flow structures. Results indicate that when S/D < 4, cylinders exhibit “multi-frequency” vibration responses. When S/D > 4, the “lock-in” region broadens, and the wake structure approaches the patterns of an isolated single cylinder; in addition, the trajectories of cylinders become more regularized. The forces acting on the central cylinder present characteristics of stochastic synchronization, significantly different from those observed in two-cylinder systems. The results can advance the understanding of complex interactions between hydrodynamic and structural dynamic forces under different geometric parameters that govern VIV response characteristics of marine structures. Full article

Uncaria rhynchophylla, a medicinal plant extensively used in traditional Chinese medicine, is an important plant source of terpenoid indole alkaloids (TIAs), but the mechanism of TIA biosynthesis at molecular level remains unclear. Geraniol synthase (GES) serves as a crucial enzyme in catalyzing the formation of geraniol from geranyl pyrophosphate (GPP) in various plants, but the functional characterization of the GES gene in U. rhynchophylla has not been investigated. In this study, a GES was identified and characterized through genome mining and bioinformatic analysis. Functional validation was performed via a protein catalysis experiment, transient expression in Nicotiana benthamiana, and methyl jasmonate (MeJA) induction experiments. The full-length UrGES gene was 1761 bp, encoding a protein product of 586 amino acids with an estimated 67.5 kDa molecular weight. Multiple sequence alignments and phylogenetic analysis placed UrGES within the terpene synthase g (TPS-g) subfamily, showing high similarity to known GESs from other plants. Enzymatic assays confirmed that recombinant UrGES catalyzed GPP conversion to a single product of geraniol. The transient expression of UrGES resulted in geraniol accumulation in N. benthamiana, further confirming its function in vivo. UrGES expression was observed in leaves, stems, and roots, where leaves had the highest transcript levels. Moreover, MeJA treatment significantly upregulated UrGES expression, which positively correlated with an increase in alkaloid content. This study functionally characterizes UrGES as a geraniol synthase in U. rhynchophylla, contributing to the current knowledge of the TIA biosynthetic pathway. These findings may offer insights for future metabolic engineering aiming to enhance TIA yields for pharmaceutical and industrial applications. Full article

Variable-rate nitrogen (VR-N) application allows farmers to optimize nitrogen (N) input site-specifically within field boundaries, enhancing both economic efficiency and environmental sustainability. In this study, VR-N technology was applied to durum wheat in two small-scale commercial fields (3–4 ha each) located in distinct agro-climatic zones of Thessaly, central Greece. A real-time VR-N application algorithm was used to calculate N rates based on easily obtainable near-real-time data from unmanned aerial vehicle (UAV) imagery, tailored to the crop’s actual needs. VR-N implementation was carried out using conventional fertilizer spreaders equipped to read prescription maps. Results showed that VR-N reduced N input by up to 49.6% compared to the conventional uniform-rate N (UR-N) application, with no significant impact on wheat yield or grain quality. In one of the fields, the improved gain of VR-N when compared to UR-N was 7.2%, corresponding to an economic gain of EUR 163.8 ha⁻¹, while in the second field—where growing conditions were less favorable—no considerable VR-N economic gain was observed. Environmental benefits were also notable. The carbon footprint (CF) of the wheat crop was reduced by 6.4% to 22.0%, and residual soil nitrate (NO₃⁻) levels at harvest were 13.6% to 36.1% lower in VR-N zones compared to UR-N zones. These findings suggest a decreased risk of NO₃⁻ leaching and ground water contamination. Overall, the study supports the viability of VR-N as a practical and scalable approach to improve N use efficiency (NUE) and reduce the environmental impact of wheat cultivation which could be readily adopted by farmers. Full article

Time-of-flight sensors have emerged as a viable solution for real-time distance sensing in robotic safety applications due to their compact size, fast response, and contactless operation. This study addresses one of the key challenges with time-of-flight sensors, focusing on how they perceive and evaluate the environment, particularly in the presence of complex geometries and reflective surfaces. Using a Universal Robots UR5e arm in a controlled indoor workspace, two different sensors were tested across eight scenarios involving objects of varying shapes, sizes, materials, and reflectivity. Quantitative metrics including the root mean square error, mean absolute error, area difference, and others were used to evaluate measurement accuracy. Results show that the sensor’s field of view and operating principle significantly affect its spatial resolution and object boundary detection, with narrower fields of view providing more precise measurements and wider fields of view demonstrating greater resilience to specular reflections. These findings offer valuable insights into selecting appropriate ToF sensors for integration into robotic safety systems, particularly in environments with reflective surfaces and complex geometries. Full article

Urban regeneration, as a key strategy for promoting sustainable development of urban areas, requires innovative digital technologies to address increasingly complex urban challenges in its implementation. With the fast advancement of digital technologies such as artificial intelligence (AI), Internet of Things (IoT), and big data, these technologies have extensively penetrated various dimensions of urban regeneration, from planning and design to implementation and post-operation management, providing new possibilities for improving urban regeneration efficiency and quality. However, the existing literature lacks a systematic evaluation of technology application patterns across different project scales and phases, comprehensive analysis of stakeholder–technology interactions, and quantitative assessment of technology distribution throughout the urban regeneration lifecycle. This research gap limits the in-depth understanding of how digital technologies can better support urban regeneration practices. This study aims to identify and quantify digital technology application patterns across urban regeneration stages, scales, and stakeholder configurations through systematic analysis of 56 high-quality articles from the Scopus and Web of Science databases. Using a mixed-methods approach combining a systematic literature review, bibliometric analysis, and meta-analysis, we categorized seven major digital technology types and analyzed their distribution patterns. Key findings reveal distinct temporal patterns: GIS and BIM/CIM technologies dominate in the pre-urban regeneration (Pre-UR) stage (10% and 12% application proportions, respectively). GIS applications increase significantly to 14% in post-urban regeneration (Post-UR) stage, while AI technology remains underutilized across all phases (2% in Pre-UR, decreasing to 1% in Post-UR). Meta-analysis reveals scale-dependent technology adoption patterns, with different technologies showing varying effectiveness at building-level, district-level, and city-level implementations. Research challenges include stakeholder digital divides, scale-dependent adoption barriers, and phase-specific implementation gaps. This study constructs a multi-dimensional analytical framework for digital technology support in urban regeneration, providing quantitative evidence for optimizing technology selection strategies. The framework offers practical guidance for policymakers and practitioners in developing context-appropriate digital technology deployment strategies for urban regeneration projects. Full article

Ultraviolet (UV) radiation can be used to inactivate microorganisms, with upper-room UV germicidal irradiation (UR-UVGI) representing a promising approach. This study investigated the inactivation of the airborne surrogate virus Phi6 by a UR-UVGI system based on light-emitting diodes (LEDs) in a realistic test setup. Two test scenarios were used, one with continuous Phi6 release, simulating a source located in the room and leading to a dynamic equilibrium, and the second simulating a situation in which the source has left the room and an exponential decay is evaluated. The “Incremental Evaluation Model” was adapted and used to evaluate the dynamic equilibrium measurement. At a position in the breathing direction 5 m away from the Phi6 source, the loss coefficient (air exchange rate) was 25 h⁻¹ in the first scenario and 30 h⁻¹ in the second. These results show that UR-UVGI systems can effectively inactivate microorganisms. However, at 1 m distance from the Phi6 source perpendicular to the breathing direction, only minimal inactivation was observed due to short-circuit airflow. At this position, the loss coefficient was <2 h⁻¹ in the first scenario and 17 h⁻¹ in the second scenario, indicating that short-circuit airflows can only be detected by dynamic equilibrium measurements. Full article

Aim: This study aimed to evaluate the potential impact of stone characteristics, patient factors, and upper tract anatomical parameters in the prediction of residual fragments (RFs) following the flexible ureteroscopic (fURS) management of renal stones. Patients and Methods: Between June 2023 and July 2024, a total of 104 cases underwent fURS for the minimally invasive management of medium-sized renal stones (10–25 mm), and 28 cases presenting with RFs 3 months after these procedures were included for further evaluation. In addition to the assessment of patient-related factors, non-contrast computed tomography (NCCT) was performed in all cases in an attempt to assess specific stone characteristics and upper tract anatomical parameters in detail during the 3-month follow-up period. Results: An evaluation of our findings indicated that, among the evaluated parameters, a higher degree of hydronephrosis (>Grade 2), a larger stone size (>15 mm), and the presence of multiple stones were found to affect the presence of RFs significantly (p = 0.020, p = 0.012, and p = 0.040, respectively). On the other hand, although the analysis of other parameters such as patient gender, stone side, stone hardness, and the use of an access sheath with univariate regression demonstrated potential correlations, none of these parameters demonstrated a significant impact when analyzed using backward logistic regression. Logistic regression revealed that Grade 2 hydronephrosis (OR = 18.3, p = 0.020), stone size > 15 mm (OR = 7.0, p = 0.012), and multiple stones (OR = 3.7, p = 0.040) significantly increased the risk of residual fragments following fURS. Conclusions: In light of our findings and published data, we can conclude that endourologists should consider the likelihood of RFs’ presence after successful stone disintegration with fURS. A detailed evaluation of the relevant factors revealed that patients with larger stones, higher degrees of hydronephrosis, and multiple calculi may carry the risk of residual fragments after these procedures. Thus, the utilization of such reliable predictive parameters may aid in selecting optimal stone removal strategies and planning subsequent interventions in the rational management of RFs. Full article

Background: Sports scientists have increasingly used point-of-care methods for training load management, and blood gas analysis has shown promise in this area. However, the reproducibility of this method in high-performance athletes remains unproven. Objective: The aim of this study was to verify the reliability of acid-base variables at rest in high-performance Paralympic sprinters. Methods: Seven athletes participated, including four with visual impairments (class T12 and T13) and three with physical impairments. Approximately 500 µL of capillary blood was obtained from the fingertip and analyzed in triplicate (Samples 1, 2, and 3) using the Epoc System^® (Ottawa, ON, Canada) to measure pH, carbonic dioxide partial pressure (pCO₂), bicarbonate ion (HCO₃⁻), base excess (BE), hematocrit (Hct), hemoglobin concentration (Hb), creatinine (CRE), and urea concentration (URE). Results: No differences were found for any parameter (p > 0.05). The imprecision of the method ranged from 0.1% for blood pH to 6.1% for BE. Pearson’s analysis showed strong and significant relationships between all variables analyzed (p < 0.05). The degree of consistency among samples also indicated excellent reliability of measurements, ranging from 0.88 for Hb to 1.00 for URE. Conclusions: These results indicate that acid-base status measurements using point-of-care demonstrated excellent reliability in high-level athletes, supporting sports scientists and coaches for athlete training and management. Full article

In hospital environments, pathogenic bacteria spread easily and acquire virulence and antibiotic resistance genes. The aim of the study was an evaluation of the genetic diversity of 109 K. pneumoniae isolates recovered from patients of a district hospital in central Poland. The frequencies of genes coding for β-lactamases, efflux pumps, and virulence factors were determined. Genotyping of the isolates was performed with ERIC (Enterobacterial Repetitive Intergenic Consensus) and REP (Repetitive Element Sequence Based) PCR techniques, with 21 and 19 genotypes being identified, respectively. The bla_SHV-1 (92.7%), bla_CTX-M group 1 (83.5%), bla_TEM-1 (28.4%), bla_NDM-1 (16.5%), bla_VEB-1 (11.0%), bla_CTX-M group 9 (3.7%), bla_KPC (1.8%), bla_IMP, bla_OXA-48, bla_CTX-M group 2, bla_CTX-M groups 8, and 25/26 (0% each) and efflux pumps: AcrAB (100%), tolC (93.6%), and mdtk (60.5%), and virulence genes coding: urease subunit ureA (94.5%) endotoxins wabG (92.7%) and uge (64.2%), and siderophore iucB (3.7%) were detected. The bla_SHV-1, bla_CTX-M group 1, mdtk, tolC, AcrAB (16.5%); bla_SHV-1, bla_CTX-M group 1, tolC, AcrAB (15.6%), and bla_SHV-1, bla_CTX-M group 1, bla_NDM-1, mdtk, tolC, AcrAB (11.9%) were the most common resistance patterns. The distribution of resistance and virulence genes varied more between hospital wards than between different clinical materials. Hospital’s antibiotic-resistant and virulent K. pneumoniae, able to spread among humans, animals, and in the environment, pose a significant threat to public health. Full article

Relying on information technologies such as the Internet, big data, and cloud computing, smart cities (SC) fully integrate urban resources, constantly strengthen the ability of urban economic systems, infrastructure systems, ecosystems, social systems, institutional systems, and other systems to withstand disaster disturbance and external risk shocks, and promote urban resilience (UR) construction. This study uses panel data from 254 prefecture-level cities in China from 2009 to 2021, and employs a multiperiod difference-in-differences method to examine the direct and heterogeneous effects of SC on UR. After a series of empirical tests, this study obtains the following results: (1) SC have a significant impact on the improvement of UR, which objectively demonstrates the reciprocity between SC and the level of UR construction, providing data support for promoting the in-depth practice of SC. (2) From the mechanism test of the impact of SC on UR, urban land green utilization efficiency and industrial structure transformation are intermediate mechanisms through which SC affect the improvement of UR. In addition, public environmental attention (PEA) has a positive regulatory effect on SC and UR, that is, PEA strengthens the role of SC in improving UR. (3) From the heterogeneity of urban characteristics that affect UR, SC have a more significant effect on improving UR in eastern cities and non-resource-based cities. This study provides new ideas for studying UR and provides useful insights for promoting SC construction and enhancing UR. This study proposes that the government should continue to promote the intelligent construction of Chinese cities, advance the industrial structure and improve the green land utilization efficiency, and strengthen their positive impact on UR. Full article

This paper presents the implementation of a vision system for a collaborative robot equipped with a web camera and a Python-based control algorithm for automated object-sorting tasks. The vision system aims to detect, classify, and manipulate objects within the robot’s workspace using only 2D camera images. The vision system was integrated with the Universal Robots UR5 cobot and designed for object sorting based on shape recognition. The software stack includes OpenCV for image processing, NumPy for numerical operations, and scikit-learn for multilayer perceptron (MLP) models. The paper outlines the calibration process, including lens distortion correction and camera-to-robot calibration in a hand-in-eye configuration to establish the spatial relationship between the camera and the cobot. Object localization relied on a virtual plane aligned with the robot’s workspace. Object classification was conducted using contour similarity with Hu moments, SIFT-based descriptors with FLANN matching, and MLP-based neural models trained on preprocessed images. Conducted performance evaluations encompassed accuracy metrics for used identification methods (MLP classifier, contour similarity, and feature descriptor matching) and the effectiveness of the vision system in controlling the cobot for sorting tasks. The evaluation focused on classification accuracy and sorting effectiveness, using sensitivity, specificity, precision, accuracy, and F1-score metrics. Results showed that neural network-based methods outperformed traditional methods in all categories, concurrently offering more straightforward implementation. Full article

Seismic isolation systems are an effective passive protection strategy that decouples structures from ground motion. Their performance depends heavily on the elastomeric materials used, which must retain mechanical integrity under environmental stressors. In recent years, low-cost isolators made from natural and recycled rubber have gained attention as an affordable solution for protecting low-rise buildings in seismic-prone developing regions, particularly due to their environmental benefits and ease of installation. However, their long-term performance under real environmental conditions remains insufficiently explored. This study evaluates the durability of two types of low-cost seismic isolators: those made with natural rubber matrices (UN-FREIs) and those that use recycled rubber matrices (UR-FREIs). Mechanical tests were carried out before and after exposing the specimens to accelerated aging and low-temperature conditions, simulating environmental degradation. Changes in stiffness, damping, and energy dissipation were analyzed for both the rubber matrix and the scaled isolator prototypes. The findings indicate that both materials degrade over time, with recycled rubber exhibiting greater susceptibility to stiffness loss at low temperatures. Nevertheless, both isolator types maintained functional performance after aging, supporting their applicability in regions with moderate thermal variations. These results provide evidence for the feasibility of adopting low-cost isolators in low-rise buildings exposed to variable climates, while also emphasizing the need for standardized durability protocols during the design stage. Full article

Long-term monoculture of poplar plantations for industrial material production has been widely reported to cause severe soil degradation, while the presence of understory vegetation might enhance soil nitrogen (N) transformation and supply. This study employed a field experiment using a randomized block design with three blocks and four understory treatments, including understory removal, N-fixing species planting, single-species retention, and diverse vegetation retention, in poplar plantations on a mid-latitude alluvial plain in China over 6 years to assess the effects of different species and richness of understory on soil N transformation and related microbial traits via ¹⁵N assays and shotgun metagenomics. The results showed that understory removal significantly reduced soil N transformation rates, bacterial abundance, and gene abundance associated with N transformation. Compared to a single-species understory, retaining a diverse understory with high species richness significantly increased soil gross N transformation rate of mineralization by 149%, nitrification by 221%, and immobilization by 85%; comprehensively enriched dominant bacterial phyla; and elevated gene abundances of gdh_K15371, ureB, hao, and amoA_B associated with N transformation. No significant difference in N transformation rates existed between N-fixing species planting treatment and single-species retention treatment, while N-fixing species planting treatment specifically promoted the soil bacterial phyla Nitrospirae and Chloroflexi, and increased the gene abundances of gdh_K15371 and hao. These findings demonstrate that both introducing N-fixing species and an increase in species richness of the understory effectively promoted soil N transformation but that different underlying mechanisms existed. Planting N-fixing species selectively increased the soil bacterial phyla of Nitrospirae and Chloroflexi, whereas the increase in species richness broadly enriched soil bacterial diversity, thereby inducing the enrichment of the functional genes and enhancing soil N transformation. In conclusion, both planting N-fixing species and retaining diverse understory vegetation were effective strategies for maintaining sustainable management of poplar plantations by increasing soil N availability. Full article

The theology of deification in the Christian tradition is fraught with misconceptions. Although it embodies the core teaching of the faith, it is not only a neglected theme of theology, but often critiqued as a Promethean distortion of the gospel and/or a semi-Pelagian heterodoxy. Hans Urs von Balthasar, through his examination of the teachings of the early Church Fathers, presents the doctrine in its Christocentric context, emphasizing its kenotic and inherently relational character. Deification is thus revealed as an antidote to the narrowly conceived notion of “justification” as salvation, which is rooted in a juridic understanding of God’s grace. Conceived as the dynamic incorporation of the believer into the life of Christ himself, deification is rightly understood as a present, existential process and thus far more than a mere eschatological hope. Full article

Shell eggs are susceptible to fecal contamination, facilitating the adhesion of microorganisms to the eggshell surface. The consumption of such eggs, especially when unwashed or raw, poses potential health risks to consumers. This study aimed to evaluate the effects of unwashed control, sodium hypochlorite (NaOCl) sanitization (150 ppm), and the combination of NaOCl and ultraviolet (UV) sanitization on the quality of eggs stored at varying temperatures over a four-week period. The findings demonstrated that NaOCl sanitization alone reduced surface bacterial counts by 1.23 log₁₀ CFU/mL, while the combination of NaOCl and UV-C irradiation achieved a greater reduction of 1.48 log₁₀ CFU/mL compared to the unwashed group. After two weeks of storage, unwashed egg groups (UC and UR) exhibited higher eggshell strength compared to NaOCl-sanitized groups (p < 0.05); however, this did not significantly influence internal contamination. Prolonged storage, particularly under refrigeration, led to increased hydroxyl (OH) group peak intensities on the eggshell, indicating dehydration and the formation of fissures in the cuticle. Elevated storage temperatures and extended durations adversely affected egg quality, whereas UV treatment did not have a detrimental impact. In conclusion, to ensure the safety and quality of shell eggs, it is recommended that they undergo NaOCl sanitization, UV irradiation, and be stored under refrigerated conditions. Full article