Variation In Position Research Articles

Revisiting the scorpion central nervous system using microCT.

The central nervous system (CNS) of Chelicerata has remained conserved since the Cambrian, yet few studies have examined its variability within chelicerate orders including Scorpiones. The scorpion CNS comprises the prosomal ganglion and opisthosomal ventral nerve cord. We visualize the scorpion CNS with microCT, explore morphological variation across taxa, compare the scorpion CNS to other arachnids, and create a terminology glossary and literature review to assist future studies. Six scorpion species were microCT scanned. Scan quality varied and most structures in the prosomal ganglion could only be observed in Paruroctonus becki (Vaejovidae). Major nerves and the first opisthosomal ganglion were visible in nearly all taxa. We present the most detailed 3D-rendering of the scorpion prosomal ganglion to date. Our results corroborate existing research and find the scorpion CNS to be conserved. Nearly all structures reported previously in the prosomal ganglion were located in similar positions in P. becki, and nerve morphology was conserved across examined families. Despite similarities, we report differences from the literature, observe taxonomic variation in prosomal ganglion shape, and confirm positional variation for the first opisthosomal ganglion. This study serves as a starting point for microCT analysis of the scorpion CNS, and future work should include more distantly related, size variable taxa to better elucidate these findings.

Factors influencing the ability of family caregivers of Alzheimer’s patients within Iranian families to continue and persist in their caregiving roles: a qualitative study

BackgroundUnderstanding the motivations driving family members to continue caring for individuals with Alzheimer’s disease is crucial for enhancing social support programs within community health systems. This study specifically explores the factors influencing Iranian family caregivers’ ability to persist in their caregiving roles.MethodsThis qualitative study was conducted using conventional content analysis with 22 participants in 2022 in Babol (a city in northern Iran). The inclusion criteria for the study included caregivers of Alzheimer’s patients who had been the primary caregivers for at least one year for patients with a confirmed diagnosis of Alzheimer’s disease. The sampling method was purposive, ensuring maximum variation in social position, demographic status, and stages of Alzheimer’s disease after the onset of symptoms. In this research, data were collected from caregivers of Alzheimer’s patients through semi-structured interviews and in-depth individual interviews. The data were analyzed using MAXQDA software.ResultsOne category and four subcategories were identified to explain the continuity of the caring role in family caregivers of Alzheimer’s patients. The category was “on the Fence of the Caring Role.” The subcategories included Commitment to Care (Being Determined, Being Indebted, Feeling Dutiful), Coercion to Care (Giving in to the Caring Role Due to Family Requirements, Patient Care Due to Financial Problems), Socio-Cultural Beliefs and Concerns (Spiritual and Religious Tendencies, Social Stigma and Social Fears), and Attachment and Love for the Patient (Feeling Pity, Feeling Nostalgia for Kinship).ConclusionFamily caregivers are deeply engaged in their roles, often feeling trapped by various pressures. Recognizing these dimensions can inform policymakers and health practitioners in developing targeted interventions, such as respite care programs, financial support, and community resources, aimed at alleviating caregiver burden and enhancing the quality of care for patients. By addressing the complexities of the caregiver experience, effective strategies can be implemented to support both patients and their caregivers, ultimately improving health outcomes within the community.

Dynamic Narrowing of the Diaphragmatic Vena Cava in Ovis aries.

Dorset sheep (Ovis aries) are common models in translational cardiovascular research due to physiologic and anatomic similarities to humans. While employing ovine subjects to study single-ventricle physiology, we repeatedly observed position-based changes in central venous pressure (CVP) which could not be explained by hydrostatic (gravitational) effects. Inferior vena cava (IVC) narrowing or compression has been demonstrated in numerous species, and we hypothesised that this phenomenon might explain our observations in O. aries. This study aimed to characterise position-dependent morphology of the IVC in O. aries using catheter-based hemodynamic and dimensional measurements, three-dimensional MRI reconstruction and histological analysis. Baseline measurements revealed a significant reduction in IVC dimensions at the level of the diaphragm (dVC) compared to the abdominal vena cava (aVC) and thoracic vena cava (tVC). We also observed a transdiaphragmatic pressure gradient along the IVC, with higher pressures in the aVC compared to the tVC. We found that variation of position and fluid status altered IVC haemodynamics. Histological data showed variable muscularity along the length of the IVC, with greater smooth muscle content in the aVC than the tVC. These findings will improve understanding of baseline ovine physiology, help refine experimental protocols and facilitate the translation of findings to the clinic.

Adductor tubercle appears more posterior on radiographs of knees with trochlear dysplasia

PurposeThe purpose of this study was to compare the radiographic positions of commonly utilized landmarks between symptomatic and normal knees and to assess the influence of morphologic risk factors. Methods3D models were created from knees of patients with patellar instability and compared to control knees. On the 3D models, the adductor tubercle, medial epicondyle and gastrocnemius tubercle were marked. A 2D view was created from these models to simulate radiographs, and the radiographic location of each landmark was described with respect to the anteroposterior relation to the posterior cortical line, and proximal-distal relationship to the posterior condylar line. The position of each landmark was compared between symptomatic and control groups and assessed for variations in position with severity of anatomic risk factors. Results40 patients were included in this study. On the 2D views, the medial epicondyle was found to be more posterior and more distal than in the control group. Association between severity of trochlear dysplasia and posterior position of the adductor tubercle trended toward significance (R=0.43, R2=0.18, p=0.058). In symptomatic knees with trochlear dysplasia, the radiographic landmark for the medial epicondyle was posterior by 3.3mm (p=0.052), adductor tubercle by 2.7mm (p=0.009), and gastrocnemius tubercle by 3.9mm (p=0.010) when compared to symptomatic knees without dysplasia. ConclusionThis study demonstrates that commonly utilized anatomic landmarks are more posterior and distal on radiographs in knees with patellar instability when compared to normal knees. Trochlear dysplasia is associated with the radiographic landmarks of the adductor and gastrocnemius tubercles appearing 3mm posterior to those without dysplasia, and its severity is associated with posterior radiographic appearance of the adductor tubercle. Level of EvidenceIII, Retrospective Case Control

Study on the influence of expansion waves on the reflection type of shock wave in double-wedge configurations

Abstract This paper investigates how variations in the relative positioning between the expansion fan emitted from the triple point in the shock/shock interference on double-wedge geometries in confined spaces and the incidence point of oblique shocks influence the transition of oblique shock reflection types, and understands the roles of expansion waves in inhibiting MR. Predictive analysis through the shock polar line provides critical values for the transition of oblique shock reflection types under the influence of expansion fan effects. The position where the shock/expansion fan undergoes post-oblique reflection on the opposite sidewall can be controlled by adjusting the model’s contraction ratio (H 1/H 2). This study uses the density-based solver blastFOAM in openFOAM to numerically solve the Euler equations, conducting inviscid calculations of shock/shock interactions induced by double wedges in confined spaces with ideal gases. This study compares pressure values in different regions obtained from numerical simulations and examines the reflection types of oblique shocks on opposite sidewalls, confirming the feasibility of shock polar analysis and the accuracy of theoretical predictions.

Few-shot Learning for Sign Language Recognition with Embedding Propagation

Sign language is a primary channel for the deaf and hard-hearing to communicate. Sign language consists of many signs with different variations in hand shapes, motion patterns, and positioning of hands, faces, and body parts. This makes sign language recognition (SLR) a challenging field in computer vision research. This paper tackles the problem of few-shot SLR, where models trained on known sign classes are utilized to recognize instances of unseen signs with only a few examples. In this approach, a transformer encoder is employed to learn the spatial and temporal features of sign gestures, and an embedding propagation technique is used to project these features into the embedding space. Subsequently, a label propagation method is applied to smooth the resulting embeddings. The obtained results demonstrate that combining embedding propagation with label propagation enhances the performance of the SLR system and achieved an accuracy of 76.6%, which surpasses the traditional few-shot prototypical network's accuracy of 72.4%.

Comparative analysis of hand dynamometer measurements across different arm positions: implications for rehabilitation and functional assessment

Background and Study Aim. Grip strength is a crucial measure of human physical capability, affecting activities from daily tasks to athletic performance. Variations in arm position during grip strength measurement may influence the results, which has significant implications for both rehabilitation and functional assessment. This study explores the impact of different arm positions on grip strength to enhance understanding of human biomechanics and inform rehabilitation and sports training practices. Material and Methods. Forty right-handed male volunteers (mean age 18.27 ± 0.90 years) participated in the study. Grip strength was measured using a CAMRY Model: EH101 hand dynamometer. Measurements were taken across four arm positions: seated with elbow extension, 90-degree elbow flexion, 90-degree elbow flexion with pronation, and 90-degree elbow flexion with supination. Each position was tested three times. The highest recorded value for each position was used for analysis. Results. The dominant right hand exhibited higher grip strength across all positions compared to the non-dominant left hand. Significant differences were noted, with the greatest grip strength in the extension position. Statistical analysis using paired t-tests indicated significant differences (p < 0.001) between the right and left hands across all positions. Pearson correlation coefficients highlighted strong relationships between different arm positions. Multiple linear regression analysis showed significant predictors of grip strength variability based on arm position, age, and BMI. Conclusions. Arm position significantly influences grip strength performance, underscoring the importance of standardized positioning in ergonomics. Standardizing arm position can optimize performance and mitigate injury risks in activities requiring robust grip strength. These findings have practical implications for rehabilitation protocols, sports training programs, and ergonomic assessments. The results emphasize the need for consistency in grip strength evaluations to ensure accurate and reliable results.

Complete Chloroplast Genome of Crassula aquatica: Comparative Genomic Analysis and Phylogenetic Relationships

Background/Objectives: Crassula aquatica (L.) Schonl. is a very small annual plant growing along riverbanks. Chloroplast (cp) genomes, crucial for photosynthesis, are highly conserved and play a key role in understanding plant evolution. In this study, we conducted cp genome analysis of C. aquatica, aiming to elucidate its phylogenetic position and structural variations. We analyzed and described the features of the complete cp genome of C. aquatica and conducted comparative analysis with the cp genomes of closely related taxa. Rsults: The cp genome was 144,503 bp in length and exhibited the typical quadripartite structure, consisting of a large single-copy region (LSC; 77,993 bp), a small single-copy region (SSC; 16,784 bp), and two inverted repeats (24,863 bp). The cp genome of C. aquatica comprised 113 unique genes, including 79 protein-coding genes (PCGs), 30 tRNAs, and 4 rRNA genes. Comparative genomic analysis of 13 other Crassula species and six outgroups demonstrated highly conserved gene content and order among Crassula species. However, notable differences were observed, including the complete loss of the rpoC1 intron in C. aquatica and several closely related species, which may serve as a synapomorphic trait supporting the monophyly of the subgenus Disporocarpa. We analyzed the nucleotide diversity among 14 Crassula cp genomes and identified five highly variable regions (pi > 0.08) in the IGS regions. Phylogenetic analysis based on 78 PCGs confirmed the monophyly of Crassula and its division into two subgenera: Crassula and Disporocarpa. Although the phylogenetic tree supported the subgeneric classification system, the sectional classification system requires reassessment. Conclusions: In this study, we conducted a comparative analysis of the cp genome of the genus Crassula. We inferred evolutionary trends within the Crassula cp genome and provided molecular evidence supporting the integration of the genus Tillaea into the genus Crassula. However, as this study does not represent all species within the genus Tillaea, further comprehensive phylogenetic analyses are requrired.

Which failures do patient-specific quality assurance systems need to catch?

The Joint AAPM-ESTRO TG-360 is developing a quantitative framework to evaluate treatment verification systems used for patient-specific quality assurance (PSQA). A subgroup was commissioned to determine which potential failure modes had the greatest risk to treatment quality and safety, and therefore should be evaluated as part of the PSQA verification. To create an extensive database of potential radiotherapy failure modes that should be detected by PSQA and to determine their relative importance for maximizing treatment quality. The subgroup consisted of eight physicists from seven countries, including representatives from three international quality assurance groups. We collected error reports from RO-ILS, SAFRON, AAPM TG publications, and other literature, including international audits. We focused on the subset of failure modes that impact whether the planned dose matches the dose received by the patient. We performed a failure-mode-and-effects analysis (FMEA), estimating the severity (S), occurrence (O), and detectability (D) of each failure mode. Detectability was scored assuming that PSQA was not done but other routine clinical QA was performed, which allowed us to see the importance of PSQA for detecting each specific failure mode. We analyzed the risk priority number (RPN=O*S*D), O*S, and severity rankings to determine the priority of each failure mode. We collected 394 error reports, which we categorized into 33 failure modes that underwent FMEA. Five failure modes were in the top ranks for both RPN and O*S analysis: four involving treatment planning system (TPS) commissioning and one regarding patient model errors. The highest-ranking RPN failure modes were: TPS algorithm limitations, TPS commissioning errors [multileaf collimator (MLC) modeling, output factor, percent-depth-dose/tissue-maximum-ratio (PDD/TMR), off-axis factor], and patient weight variation. The highest O*S failure modes were similar, with the addition of external patient position variation and incorrect linear accelerator isocenter and cGy/monitor units calibration. RPN and O*S analyses prioritized failure modes that impacted multiple patients with high occurrence and detectability scores, while severity analysis gave higher priority to single-patient modes with high severity scores. The highest-ranking severity modes were MLC sequence deletion, collision, and TPS isocenter incorrect. We have developed a list of failure modes critical to be detected during PSQA and ranked them in order of importance. The top failure modes emphasize the importance of utilizing a variety of treatment verification systems for PSQA, from secondary dose calculation through in-vivo dosimetry, in order to detect all possible errors. For failure modes in the top quartile, PSQA is critical. Without adequate PSQA, these errors may go undetected unless caught by an external audit. This analysis can be useful for optimizing PSQA workflows and for designing evaluations of treatment verification systems, and will be used by the Joint AAPM-ESTRO TG-360 to determine an appropriate validation strategy.

A reproducible representation of healthy tibiofemoral kinematics during stair descent using REFRAME – Part II: Exploring optimisation criteria and inter-subject differences

Kinematic analysis is a central component of movement biomechanics, describing the relative motion of joint segments during different activities, in different subject cohorts, and at different timepoints. Establishing whether two sets of kinematic signals represent fundamentally similar or different underlying motion patterns is especially challenging, given 1) the lack of consensus around reference frame and joint axis definition, and 2) the substantial effect that minimal variations in frame position and orientation are known to have on signal magnitude and characteristics. As such, enormous variability in the reporting of tibiofemoral kinematics has resulted in joint movement patterns that remain controversially discussed. Previously, we demonstrated the ability of the REference FRame Alignment MEthod (REFRAME) to reorientate and reposition differently aligned local segment frames to achieve convergence in signals representing the same underlying motion, thereby offering a novel approach to consistently report joint motion. In this study, for the first time, we apply REFRAME to assess the rotational and translational in vivo tibiofemoral motion of ten healthy subjects during stair descent based on kinematic signals collected using a moving videofluoroscope. Kinematics were analysed before and after different REFRAME implementations, revealing generally neutral ab/adduction behaviour, accompanied by varying degrees of a sinusoidal int/external tibial rotation pattern over the activity cycle. Our data demonstrate that different selected implementations of REFRAME are able to highlight different characteristics of the motion patterns: Minimisation of the translational root-mean-square revealed proximodistal translation patterns with overall neutral progression, while anteroposterior translation showed seemingly different levels of correlation with flexion/extension in different subjects. On the other hand, REFRAME minimisation of translational variances exposed differences in the relative mean displacement between the femoral and tibial origins between subjects, highlighting differences in mean centre of rotation positions. This early application of REFRAME for providing an understanding of tibiofemoral kinematics demonstrates the potential of this novel approach to bring clarity to an otherwise complex representation of highly variable time-series signals, while highlighting the philosophical challenges of clinically interpretating kinematic signals in the first place.

A microwave permittivity sensor on a Mach–Zehnder Interferometer of: Spoof surface plasmon polariton waveguides

A microwave Mach–Zehnder Interferometer (MZI) sensor for the permittivity characterization of liquids is presented in this paper. Two spoof surface plasmon polariton (SSPP) waveguide transmission lines (TLs) composed of compact spiral units is utilized in a differential architecture. Loading a dielectric material on the sensing arm induces a phase difference between the two arms, leading to periodic interference dips on the transmission curve. The spectral positions and magnitudes of these dips change with different dielectric materials. Due to the nonlinear dispersion characteristics of the SSPP TL, the proposed SSPP-based MZI sensor achieves improved sensitivity compared with microstrip-based MZI sensor. To validate the sensor’s performance, six different oil samples and a set of adulterated oils were measured, incorporating a polydimethylsiloxane (PDMS) channel on the sensing arm. The variations in the spectral position and magnitude of the interference dip centered at 3.2 GHz are employed to determine the dielectric constants and loss tangents of the tested oils. The sensitivity in measuring the dielectric constant is 3.61 %. The maximum errors for measuring the dielectric constant and the loss tangent are 4.3 % and 6.7 %, respectively. Compared to other sensors for liquid oil detection, the proposed sensor provides a relatively high sensitivity while maintaining a low liquid volume, making it a promising candidate for permittivity measurements of liquid analytes and solid materials with similar dielectric constants.

How the Aliphatic Glycol Chain Length Determines the Pseudoeutectic Composition in Biodegradable Isodimorphic poly(alkylene succinate-ran-caprolactone) Random Copolyesters.

We synthesize four series of novel biodegradable poly(alkylene succinate-ran-caprolactone) random copolyesters using a two-step ring-opening/transesterification and polycondensation process with ε-caprolactone (PCL) as a common comonomer. The second comonomers are succinic acid derivatives, with variations in the number of methylene groups (nCH2) in the glycol segment, nCH2 = 2, 4, 8, and 12. The obtained copolyesters were poly(ethylene succinate-ran-PCL) (ESxCLy), poly(butylene succinate-ran-PCL) (BSxCLy), poly(octamethylene succinate-ran-PCL) (OSxCLy), and poly(dodecylene succinate-ran-PCL) (DSxCLy). We discovered a new mixed isodimorphic/comonomer exclusion crystallization in ESxCLy copolymers. The BSxCLy, OSxCLy, and DSxCLy copolymers display isodimorphic behavior. Our findings revealed a significant variation in the pseudoeutectic point position, from mixed isodimorphism/comonomer exclusion crystallization to isodimorphism with pseudoeutectic point variation from 54% to up to 90%. Moreover, we established a link between the melting temperature depression slope variation and the comonomer inclusion/exclusion balance, providing valuable insights into the complex topic of isodimorphic random copolymers.

Dosimetric benefit and clinical feasibility of deep inspiration breath-hold and volumetric modulated arc therapy-based postmastectomy radiotherapy for left-sided breast cancer

To evaluate the dosimetric benefits and clinical feasibility of deep inspiratory breath-hold (DIBH) combined with volumetric modulated arc therapy (VMAT) in left-sided postmastectomy radiotherapy (PMRT). Eligible patients with left-sided breast cancer undergoing DIBH-based PMRT were prospectively included. Chest wall, supra/infraclavicular fossa, and/or internal mammary node irradiation (IMNI) were planned with a prescription dose of 43.5 Gy in 15 fractions. VMAT plans were designed on free breathing (FB)—and DIBH-CT to compare dosimetric parameters in heart, left anterior descending artery (LAD) and lung. Cone-beam computed tomography (CBCT) was performed before and after treatment to evaluate inter- and intra-fractional setup errors. Heart position and dose variations during treatment were estimated by fusing CBCT with DIBH-CT scans.Twenty patients were included with 10 receiving IMNI. In total, 193 pre-treatment and 39 pairs pre- and post-treatment CBCT scans were analyzed. The Dmean, Dmax, and V5−40 of the heart, LAD, and left lung were significantly lower in DIBH than FB (p < 0.05 for all), except for V5 of LAD (p = 0.167). The cardiopulmonary dosimetric benefits were maintained regardless of IMNI. The inter- and intra-fractional setup errors were < 0.3 cm; and the overall estimated PTV margins were < 1.0 cm. During treatment, the mean dice similarity coefficient of heart position and the mean ratio of heart Dmean between CBCT and DIBH-CT plans was 0.95 (0.88–1.00) and 100% (70.6–119.5%), respectively. DIBH-VMAT could effectively reduce the cardiopulmonary doses with acceptable reproducibility and stability in left-sided PMRT regardless of IMNI.

Strengthening Transformer Tank Structural Integrity through Economic Stiffener Design Configurations Using Computational Analysis

Power transformers play a vital role in adjusting voltage levels during transmission. This study focuses on optimizing the structural design of power transformer tanks, particularly high-voltage (HV) tank walls, to enhance their mechanical robustness, performance, and operational reliability. This research investigates various stiffener designs and their impact on stress distribution and deformation through finite element analysis (FEA). Ten different configurations of stiffeners, including thickness, width, type, and position variations, were evaluated to identify the optimal design that minimizes stress and deflection while considering weight constraints. The results indicate that specific configurations, particularly those incorporating 16 mm thick H beams, significantly enhance structural integrity. Experimental validation through pressure testing corroborated the simulation findings, ensuring the practical applicability of the optimized designs. This study’s findings have implications for enhancing the longevity and reliability of power transformers, ultimately contributing to more efficient and resilient power transmission systems.

How the vertical gradient of light in the understorey and water seasonality affect leaf traits of Vanilla phaeantha (Orchidaceae), a crassulacean acid metabolism (CAM) hemiephyte.

Structural and physiological leaf traits and their plasticity were compared in the hemiepiphyte Vanilla phaeantha . This species grows along a phorophyte reaching different understorey positions and exhibiting diverse responses to environment changes. We analysed three height strata above the ground, establishing a light gradient, and considering seasonal water fluctuations. The upper leaves had higher area and mass and were less pigmented. The dry season induced a reduction of approximately 2h of stomatal opening over the diel 24h crassulacean acid metabolism (CAM) cycle in the leaves at all understorey positions. The leaves more exposed to sunlight were larger with higher titratable acidity during the rainy season, while the leaves near the ground maintained the same rates of stomatal conductance and nocturnal acidification between seasons, with lowest values of carbon isotopes in the rainy season. Our research showed that some structural leaf traits (such as specific leaf mass, biomass, and saturated water content) are sensitive to variation in understorey position. In contrast, other physiological traits (stomatal conductance, transpiration, and fluorescence parameters) are more sensitive to seasonal variations. The results are a novelty in assessing the variation of CAM along the same plant in a height gradient and under field conditions.

Non-destructive Analytical Study of Raman Spectra Variations and Mechanisms of Calcite and Aragonite in Modern and Fossilized Oysters.

Oyster fossils are some of the most common bivalve mollusk fossils found all over the world, they are different from other fossils because the oyster is still alive in the present day, and the body structure of modern oyster is almost the same as that of ancient one. Therefore, we designed a control experiment comparing the Raman spectra of minerals from both modern oysters and fossil oysters to explore the mechanism of oyster's fossilization process, which is considered to be helpful for investigating biological evolution or paleoenvironment. The oyster fossil sample was found in Nagi-Cho, Okayama Prefecture, Japan. We focused on the variations of band position and full width half-maximum of ν1 Raman band (symmetric stretching mode) of calcite (CaCO3) from modern and fossil oysters and the mineral conversion between calcite and aragonite (CaCO3) around the adductor muscle inside the oyster. Compared to modern oysters, the ν1 band at around 1086 cm-1 of calcite from oyster fossils shifted to a high wavenumber region, and the possible reason for this phenomenon is considered an elemental substitution between Ca2+ and Mg2+. As for aragonite around adductor muscle in fossil oysters, it has been found by Raman spectra that most of the aragonite has been converted into calcite because calcite has a relatively more stable structure.

Biocatalytic degradation of environmental endocrine disruptor chlorobenzene via surfactant-optimized laccase-mediator system.

The emergence of environmental endocrine disruptor chlorobenzene (CB) in surface water and its potential environmental impacts have attracted serious global attention. It is still very difficult to achieve effective degradation of it by catalytic oxidation process under mild conditions. Here, an optimized method for degrading CB in aqueous solution using Trametes versicolor laccase and surfactant-assisted laccase-mediator (SALM) system was investigated. The use of a Tween 80 surfactant enhanced the solubility of CB and promoted its efficient degradation. Under favorable conditions, the SALM system yielded a degradation efficiency of 43.5% and a dechlorination efficiency of 41.55% for CB (25mg/L) within 24h. The possible degradation pathway of CB by this system was speculated by detecting the intermediates produced during the reaction. The outcome of the proliferation assays on MCF-7 human breast cancer cells demonstrated a reduction in the estrogenic activity of the CB solution following treatment with the SALM system. Furthermore, the influence of the quantity and positional variation of chlorine substituents on the degradation process was methodically investigated. Moreover, molecular analyses were employed to study the detailed interaction mechanism between laccase and CB, which revealed that the hydrophobic interaction contributed dominantly to binding process. These findings provide an efficient and environmentally friendly degradation system for the development of purification strategies for halogenated pollutants.

Welding Defect Monitoring Based on Multi-Scale Feature Fusion of Molten Pool Videos.

Real-time quality monitoring through molten pool images is a critical focus in researching high-quality, intelligent automated welding. However, challenges such as the dynamic nature of the molten pool, changes in camera perspective, and variations in pool shape make defect detection using single-frame images difficult. We propose a multi-scale fusion method for defect monitoring based on molten pool videos to address these issues. This method analyzes the temporal changes in light spots on the molten pool surface, transferring features between frames to capture dynamic behavior. Our approach employs multi-scale feature fusion using row and column convolutions along with a gated fusion module to accommodate variations in pool size and position, enabling the detection of light spot changes of different sizes and directions from coarse to fine. Additionally, incorporating mixed attention with row and column features enables the model to capture the characteristics of the molten pool more efficiently. Our method achieves an accuracy of 97.416% on a molten pool video dataset, with a processing time of 16 ms per sample. Experimental results on the UCF101-24 and JHMDB datasets also demonstrate the method's generalization capability.

Effects of Anthropic Structures on Morphodynamic Beach Evolution along the Gulf of Roses (Northwestern Mediterranean, Spain)

This study conducts a morphodynamic analysis of beaches located in the northern sector of the Gulf of Roses (NW Mediterranean, Spain). The primary objective is to investigate mid-short (2004–2020) term spatial and temporal variations in shoreline position and sedimentological behaviour. The study area covers the northern part of the gulf, spanning 9.86 km, and includes both natural beaches and heavily anthropized ones. The following GIS methodologies were employed to study the variations in the coastline: QGIS for areas and DSAS-ArcGIS for transects, quantifying coastal changes from 2004 to 2020. Sediment samples were collected from both the dry beach and swash areas for each profile. The results reveal minor discrepancies in shoreline evolution data, depending on the method used (transects or areas). Profile-based analysis shows an average annual rate of −0.11 m·y−1 (ranging between 0.53 and −0.55 m·y−1), while areal-based results (2004–2020) indicate a total loss of −20,810 m2 (−1300 m2·y−1). Sediment grain size decreases northward (from 745 to 264 µm in the swash zone). Changes in shoreline position and grain size illustrate the impact of various anthropogenic structures on morphodynamic behaviour. These structures preferentially deposit specific grain sizes and impede sediment transport, which will cause an advance in the position of the shoreline and sediment grain sizes upstream and a reverse process downstream. This study underscores the influence of coastal anthropization on beach morphology and sedimentology, generating distinct morphodynamic behaviour.

Attention-based convolutional neural network for multi-channel active noise control

Multi-channel active noise control systems utilize multiple control units to cancel unwanted noise across different channels simultaneously. By employing adaptive filtering techniques, these systems can effectively reduce noise levels in complex environments, offering improved noise mitigation compared to single-channel active noise control approaches. The disadvantage of adaptive filtering in active noise control is its limited ability to accurately model nonlinearities present in real-world noise environments. In this work, we propose an attention-based convolutional neural network comprising convolutional, deconvolutional, and attention mechanism to approach multi-channel active noise control. The system simultaneously calculates multiple canceling signals to eliminate primary noises captured by error microphones. To evaluate the effectiveness of our proposed model, we conducted testing utilizing filtered white noise spanning various frequency bands. Experimental evaluations across various setups, including different loudspeaker and microphone configurations, as well as variations in secondary source positioning, are used to assess the performance of the proposed approach. Results demonstrate that the proposed attention-based convolutional neural network for multi-channel active noise control yields a noise reduction of 22.65 dB on wideband noise, while the conventional Filtered-x least mean square approach yields a noise reduction of 4.23 dB, indicating the effectiveness of the proposed approach.