Scientific Reports最新文献

As vehicular applications become increasingly complex, their computational demands often exceed the capabilities of individual vehicles. Vehicular Edge Computing (VEC) alleviates this limitation by enabling task delegation to nearby edge resources; however, high mobility, dynamic topology, and fluctuating vehicle density make real-time offloading decisions challenging. To address these issues, we propose a performance-optimized Vehicle-to-Vehicle (V2V) task offloading framework for dense and dynamic Vehicular Ad-hoc Networks (VANETs). The framework follows a two-stage design: (i) context-aware edge-node selection based on live topology capture via periodic beaconing, and (ii) cumulative score-based dynamic priority queuing at the selected edge node. The priority score jointly considers relative speed, distance, task size, and task priority, and its weights can be tuned to match application requirements and network conditions. Using OMNeT++/Veins/SUMO simulations, we evaluate dissemination and system delay, packet delivery ratio, task completion/success rate, and task processing failure rate. Results show improvements of up to 27% in system delay, 18% in packet delivery ratio, and 24% in task completion ratio compared with representative baselines, demonstrating robust performance under high density and mobility.

Myostatin (MSTN) is a well-established negative regulator of muscle growth and development in mammals. Genetic variations within MSTN are linked to differences in sheep musculature, particularly the double-muscle phenotype. This study represents the first comprehensive polymorphism analysis within intron 1 of the MSTN in the Ukrainian Carpathian Mountain (UCM) sheep breed combining molecular and bioinformatic approaches. Sequencing data of samples from UCM sheep revealed eight previously reported single-nucleotide polymorphisms (c.373+241T>C, c.373+243G>A, c.373+246T>C, c.373+249T>C, c.373+259G>T, c.373+323C>T, c.373+563G>A, c.373+607G>A) and one novel polymorphism (c.373+283T>C). Bioinformatic analysis evaluated potential functional effects of these intronic polymorphisms, including changes in pre-mRNA stability, proximity to transcription factor binding sites, and possible pre-miRNA formation, using in silico approaches, including molecular dynamics simulations of predicted pre-miRNA structures. Predictions identified c.373+607G>A and the novel c.373+283T>C polymorphisms as potential candidates for further functional investigation and association studies. This study demonstrates the value of combining molecular genetic and bioinformatic approaches for characterizing intronic polymorphisms and supporting a deeper understanding of functional genetic variation in livestock.

Visual dependence (VD) is heightened in pathologies where balance is compromised. It is measured using the Rod and Disk Test (RDT), traditionally delivered through a personal computer (PC). This restricts settings under which the test can be taken. This study aimed to evaluate validity, reliability and measurement precision of a novel virtual reality (VR) RDT. VD of 15 healthy participants and 15 people with symptomatic hypermobility was assessed using VR- and PC-based RDT to evaluate convergent validity. Assessments were conducted in three head positions. Intra-rater reliability was assessed by measuring VD of 15 healthy participants seven days apart. Convergent validity was evaluated using correlation analysis; intra-rater reliability using intraclass correlation coefficients. Bland-Altman plots assessed agreement, and measurement precision was reported as standard error of measurement (SEM) and minimal detectable change (MDC). Weak to moderate convergent validity was seen between VR- and PC-based tests, with coefficients of 0.3, 0.4 and 0.3. PC-based RDT showed poor to moderate ICCs; the VR-based RDT demonstrated poor ICCs. SEM and MDC for PC ranged from 0.44-0.47° and 1.23-1.30° respectively; for VR they ranged from 0.65-0.78° and 1.81-2.17° respectively. VR-based RDT demonstrated weak to moderate convergent validity and poor intra-rater reliability.

We introduce the study of the visual perception of longitudinal travelling wave motion, which as a physical phenomenon forms the basis of acoustics and some forms of seismic transmission. A theoretical analysis of physical longitudinal wave motion reveals that it exhibits profound nonlinearities that have been almost entirely neglected by the physics community. We simulated longitudinal motion in visual form with a random-dot field in which each dot particle oscillates sinusoidally about a fixed position at the same frequency but with a phase advance proportional to its distance from the origin. The resultant longitudinal density wave is essentially sinusoidal at very low oscillation amplitudes, becoming progressively distorted as oscillation amplitude increases. Perceptually, the motion splits into a combination of forward motion of the crests and backward for the troughs, rather than a uniform travelling wave. When the maximum velocity of each dot particle equals that of the propagation, the density function approximates a narrow spike, which splits into a double spike at even greater amplitudes. Adding a single ('rigid') velocity component can eliminate either the forward or backward percept. Remarkably, the speed needed for perceptual cancellation scales with oscillation amplitude, but nonlinearly so for the forward crest motion. Longitudinal waves evoked no motion aftereffect at any amplitude unless the contrast of the forward crest motion was reduced, revealing a motion aftereffect from the now-dominant retrograde trough motion. These unexpected results underline the emergent, or higher-order, nature of the perception of longitudinal travelling wave motion.

The aim of this study was to evaluate groundwater quality the Marvdasht aquifer using the Groundwater Quality Index (GWQI), which was determined using a conventional method and also predicted using three machine learning algorithms: Artificial Neural Network (ANN), Support Vector Machine (SVM) and Random Forest (RF). For this purpose, groundwater quality parameters (pH, EC, TDS, TH, Na⁺, Ca²⁺, Mg²⁺, Cl⁻, HCO₃⁻, SO₄²⁻, and K⁺) were measured. The GWQI was calculated based on WHO drinking-water standards, and a spatial map was generated in ArcGIS. Results showed that TDS, EC, Na⁺, Cl⁻, and Mg²⁺ were the most influential parameters controlling groundwater quality. The groundwater quality was classified as hard to very hard and not suitable for drinking purposes in the southern and southeastern areas of the study site, while the northern area showed good quality due to limestone formations and recharge from a dam. Results also revealed that Na-Cl was the dominant water type, which indicates the groundwater evolution through rock-water interaction, dissolution, and evaporation. TDS mean variation index of 27.8 and EC with mean variation index of 15.7 were selected as the most sensitive quality parameters in GWQI calculation. Among the applied models, the ANN provided the highest accuracy (R² = 0.999; RMSE = 1.02), followed by SVM and RF for predicting GWQI from groundwater quality parameters. It was concluded that the integration of GWQI, ANN, and GIS effectively captured spatial variations and provided a reliable framework for groundwater monitoring in arid regions.

Most human invasive infections caused by extraintestinal pathogenic Escherichia coli (ExPEC) are associated with a limited number of O-serotypes and O-serogroups, including O101/O162. Here, we examined E. coli O101/O162 O-serogroup epidemiology among bacteremia isolates and performed genetic, biochemical and structural analyses. We demonstrate that the O101/O162 O-serogroup is globally widespread and highly associated with multidrug resistance (MDR). Dominant lineages belonged to clonal complex 10, including the high-risk clone ST167. Most O101/O162 ExPEC isolates contained an unusual O101 rfb locus previously identified as Onovel32, of which 30% harbored disruptions in the methyltransferase (MT) encoding gene. These disruptions resulted in alteration of the polysaccharide composition, and we identified two major O101 variants. Additionally, we found that an intact MT is a prerequisite for O-methylation of the polysaccharide, indicating terminal capping. Our data supports a model of a co-polymeric O101 O-antigen structure, which is unique for E. coli. Finally, we established that the two clinically relevant O101 O-antigen variant structures are highly immunogenic as polysaccharide-protein conjugates but differ in their ability to elicit opsonophagocytic antibodies. Altogether, our data provides important insights into O-serotype epidemiology and O-polysaccharide variation within E. coli O101/O162 isolates associated with bacteremia.