Search Results (1,237)

Background: Sphenoid wing meningiomas (SWM) frequently compress structures of the optic pathway, resulting in significant visual dysfunction characterized by vision loss and visual field deficits, which profoundly impact patients’ quality of life (QoL), daily activities, and independence. The objective of this study was to assess the impact of SWM surgery on patient-reported outcome measures (PROMs) regarding postoperative visual function. Methods: The Visual Function Score Questionnaire (VFQ-25) is a validated tool designed to assess the impact of visual impairment on quality of life. The questionnaire was distributed to a previously published study population in which shape radiomics were correlated with new cranial nerve deficits after SWM surgery. Results: A total of 42 patients (42/74; 56.8%) responded to the questionnaire. Of the 42 patients, 30 were female (71%) and 12 were male (29%). The multivariable analysis demonstrated that lower sphericity reflecting irregular SWM shape was associated with poorer VFQ-25 (OR: 6.8, 95% CI: 1.141.8, p = 0.039), while age was associated with lower VFQ-25 (OR: 27, 95% CI: 2.7−272.93, p = 0.005), too. Analysis of the subcategories of the VFQ-25 revealed significantly reduced general vision (p = 0.045), social functioning (p = 0.045), and peripheral vision (p = 0.017) in those with SWM with low sphericity. Conclusions: The study highlights that SWM surgery impacts postoperative visual function, with age and irregular SWM shape being associated with poorer postoperative VFQ-25 scores. VFQ-25 is a feasible tool to assess vision outcome in SWM surgery and has clinical potential for longitudinal follow-up evaluations. Irregular SWM shape should be considered during preoperative treatment planning and patient consultation regarding functional outcome. Full article

This paper aims to investigate the effects of asteroid size and shape and solar radiation pressure in the trajectories of a spacecraft in transfers between the collinear equilibrium points of a binary non-spherical asteroid system. As an example, we consider the physical and orbital characteristics of the asteroid system 2001SN263. The goal is not to study this system in detail, but to use its parameters to search for transfers considering elongated bodies for the asteroids and compare the results with the solutions obtained when modeling the bodies as point masses. For the propulsion system, bi-impulsive transfers were investigated. In a system composed of asteroids, it is important to take into account the elongation of the asteroids, particularly the body with the most irregular shape, as this has been shown to change the optimal transfer trajectories. By incorporating solar radiation pressure and the size of the bodies into the dynamics, solutions with both lower and higher fuel consumption can be identified. Although the irregular shape and radiation pressure were not used as controls, their effects on the transfers are analyzed. For a system of small bodies, such as an asteroid system, it is very important to consider these perturbations to ensure that the spacecraft will reach the desired point. Full article

This paper presents a comprehensive study of the signed distance metric for fuzzy numbers. Due to the property of directionality, this measure has been widely used. However, it has a main drawback in handling asymmetry and irregular shapes in fuzzy numbers. To overcome this rather bad feature, we introduce two new distances, the balanced signed distance (BSGD) and the generalised signed distance (GSGD), seen as generalisations of the classical signed distance. The developed distances successfully and effectively take into account the shape, the asymmetry and the overlap of fuzzy numbers. The GSGD is additionally directional, while the BSGD satisfies the requirements for being a metric of fuzzy quantities. Analytical simplifications of both distances in the case of often-used particular types of fuzzy numbers are provided to simplify the computation process, making them as simple as the classical signed distance but more realistic and precise. We empirically analyse the sensitivity of these distances. Considering several scenarios of fuzzy numbers, we also numerically compare these distances against established metrics, highlighting the advantages of the BSGD and the GSGD in capturing the shape properties of fuzzy numbers. One main finding of this research is that the defended distances capture with great precision the distance between fuzzy numbers; additionally, they are theoretically appealing and are computationally easy for traditional fuzzy numbers such as triangular, trapezoidal, Gaussian, etc., making these metrics promising. Full article

This work investigates the contact between abrasive particles and workpieces in microfinishing processes with special consideration given to the determination of unit force, unit pressure, and grain, the forces exerted by individual abrasive grains. A detailed methodology was established for measuring the contact area, penetration depth, and circumferences of grain imprints at depths corresponding to multiples of the total height of the abrasive film, represented by the parameter Sz. The following depths were analyzed: 0.05 Sz, 0.15 Sz, 0.25 Sz, and 0.35 Sz. Results show that the areas closer to the central microfinishing zone bear the highest unit pressures and forces and, thus, contribute dominantly to material removal. It was further found that near the edges of the contact zone, the pressure and force have been reduced to lower material removal efficiency. The non-uniform geometry of abrasive particles was found to significantly affect contact mechanics, more at shallow depths of penetration, whereas the shape of the apex defines the nature of the interaction. A parabolic force and pressure distribution were evident for the irregular load distribution of the microfinishing area. The result brings out the need for further refinement in the design of the abrasive film and pressure distribution in order to achieve improvement in uniformity and efficiency during microfinishing. It would bring out valuable insights on how to improve the effectiveness of an abrasive film and ways of optimizing the process conditions. The results provide a founding stone for further advancement of knowledge in the grain–workpiece interaction, enabling better surface quality and more reliable microfinishing processes. Full article

The correlation between the morphology and crystal structure of zinc dendritic particles produced by electrolysis from the alkaline electrolyte has been established. Morphology and crystal structure of Zn particles electrodeposited by the potentiostatic regime of electrolysis at overpotentials inside (−100 and −160 mV) and outside (−220, −280, and −340 mV) the plateau of the limiting diffusion current density were characterized by scanning electron microscope (SEM) and by X-ray diffraction (XRD), respectively. The particle size distribution (PSD) was performed in order to determine the dependency of the size of dendritic particles on applied electrolysis overpotential. With increasing the overpotential of electrolysis, the shape of particles changed from irregular forms denoted as precursors of dendrites to various forms of dendrites, while the size of the particles simultaneously decreased. All types of Zn dendrites exhibited the strong (002) preferred orientation, while the precursors of dendrites exhibited (101)(002) preferred orientation. The development of strong (002) preferred orientation was explained and discussed by making an analogy with the electrolytic production of lead dendrites from the concentrated nitrate electrolyte. Although zinc and lead belong to different types of crystal lattice (Pb-face-centered cubic type and Zn-hexagonal close-packed type), they have a common characteristic that is manifested by the strong preferred orientation in the crystal plane with the lowest surface energy. Full article

As one of the important features in the early stage of fires, the detection of smoke can provide a faster early warning of a fire, thus suppressing the spread of the fire in time. However, the features of smoke are not apparent; the shape of smoke is not fixed, and it is easy to be confused with the background outdoors, which leads to difficulties in detecting smoke. Therefore, this study proposes a model called Smoke Detection Transformer (Smoke-DETR) for smoke detection, which is based on a Real-Time Detection Transformer (RT-DETR). Considering the limited computational resources of smoke detection devices, Enhanced Channel-wise Partial Convolution (ECPConv) is introduced to reduce the number of parameters and the amount of computation. This approach improves Partial Convolution (PConv) by using a selection strategy that selects channels containing more information for each convolution, thereby increasing the network’s ability to learn smoke features. To cope with smoke images with inconspicuous features and irregular shapes, the Efficient Multi-Scale Attention (EMA) module is used to strengthen the feature extraction capability of the backbone network. Additionally, in order to overcome the problem of smoke being easily confused with the background, the Multi-Scale Foreground-Focus Fusion Pyramid Network (MFFPN) is designed to strengthen the model’s attention to the foreground of images, which improves the accuracy of detection in situations where smoke is not well differentiated from the background. Experimental results demonstrate that Smoke-DETR has achieved significant improvements in smoke detection. In the self-building dataset, compared to RT-DETR, Smoke-DETR achieves a Precision that has reached 86.2%, marking an increase of 3.6 percentage points. Similarly, Recall has achieved 80%, showing an improvement of 3.6 percentage points. In terms of mAP50, it has reached 86.2%, with a 3.8 percentage point increase. Furthermore, mAP50 has reached 53.9%, representing a 3.6 percentage point increase. Full article

The exponential increase in population has led to a shortage of land for constructing tall buildings, resulting in the need to design irregular structures due to the limited availability of land. Assessing the impact of wind-generated effects can be achieved utilizing the Computational Fluid Dynamics (CFD) method, specifically employing ANSYS. This involves resolving the intricate fluid dynamics problem through numerical analysis using the ANSYS software. The validation study is performed on a standard shape-building model where the result is compared with experimental values and other international standards. The outcomes are presented in a graphical format, such as mean pressure, streamline, and pressure distribution in the vertical and horizontal planes. This research has studied four building models with equal area and height. Models A and B have regular shapes, while Models C and D exhibit an irregular ‘Y’ shape. The wind incidence angle was adjusted between 0 and 180 degrees at every 15-degree interval. The results were validated to ensure the accuracy of the numerical techniques employed. This involved performing validation and grid sensitivity analyses, which showed consistent results comparable to experimental data and established international standards. Model-C irregular-shaped buildings demonstrated the highest efficiency in minimizing wind loads among the building models examined in this study. Full article

In managing ulcerative colitis (UC), anti-tumour necrosis factor (TNF) agents are among the primary choices. Evidence suggests anti-TNF does not significantly increase malignancy risk (apart from lymphoma and melanoma), though uncertainties persist due to inconsistent long-term data. Kaposi’s sarcoma (KS), induced by human herpesvirus type-8 (HHV-8), is a multifocal neoplasm linked to immunosuppressive therapies, primarily affecting the skin and gastrointestinal tract. KS cases during anti-TNF therapy for UC are anecdotal. We report a rare occurrence of KS in the setting of the long-term use of the standard maintenance dose of infliximab (initiated in 2010) in a 56-year-old male patient with UC diagnosed in 2001. The patient underwent restorative proctocolectomy with ileal J-pouch-anal anastomosis in 2002 and subsequently developed chronic antibiotic-dependent pouchitis. Given the secondary loss of response to infliximab, a switch to vedolizumab was performed. In April 2024, the patient reported the presence of a skin lesion on the right leg. Following surgery, a rhomboid-shaped skin area was removed, encompassing the irregular, greyish KS lesion. The histopathological analysis confirmed the diagnosis of patch-like KS. We continued vedolizumab due to its gut-selective profile. The patient is in clinical remission and under dermatological follow-up with no lesion recurrence. Full article

The manufacturing of work parts made of powder (sintered) steels is currently widespread in industry, as it provides minimal processing allowances and high dimensional accuracy, as well as the required properties and unconventional chemical composition. At the same time, their low tensile or bending strength must be considered a serious disadvantage. In order to minimize these disadvantages, a number of strengthening technologies are used, among which is the infiltration of porous base materials with metal alloys. In this study, the details of finish turning of sintered iron-graphite-based steel infiltrated with tin bronze with molybdenum disulfide addition are considered. Changes in the shape of chips and their geometric features, as well as the 3D parameters and topography features of the surface machined, are presented after finish turning with AH8015 carbide inserts. The cutting speed (v_c) and feed rate (f) were used as variable parameters. It was found that when turning the powder steels under study, the chips took the shape of small fragments or element chips, including segmented chips. For quenching steel, the formation of irregular lamellae was observed and for the initial state, a serrated chip was registered. For the initial state, a reduction in K_b values was observed in the range of the v_c of 50–100 m/min and f of 0.05–0.075 mm/rev, and for quenching in the range of 225–250 m/min and 0.05–0.075 mm/rev. Compared to the initial state, for quenching, depending on the cutting parameters, a 14% reduction in the chip spreading ratio K_b or an increase from 2 to 32% was registered. For the initial state and quenching, a decrease in the Sp and Sv parameters was achieved in the range of the v_c of 200–250 m/min and f of 0.05–0.075 mm/rev, and there was an increase in the range of 50–150 m/min and 0.125–0.15 mm/rev. Compared to the initial state, an increase in the Sz parameter from 10 to 35% was observed for quenching. On the surfaces machined with v_c = 50 m/min and f = 0.05 mm/rev, waves and single significant peaks were observed. On the other hand, v_c = 250 m/min and f = 0.15 mm/rev provided classical feed tracks in the form of valleys and irregular ridges on the surfaces machined. The test results can be useful in the design and manufacturing of industrial parts made of powder steels. Full article

Due to the need to form a surface layer with specific operating properties, recent years have seen an increased interest in surface strengthening treatment, which aims to create a surface layer that improves the durability of parts. With a view to the economics of the machining process, it is common to combine shaping milling, characterised by high volumetric efficiency, with finishing burnishing, during which significant forces are applied. In the literature, one of the important limitations of such technological operations is the value of residual stresses, excessive values of which can lead to the flaking and falling off of surface fragments. In the present study, the authors put forward the research hypothesis that, in addition to stresses, the geometry of the machining roughness is also important and may contribute to faster tribological wear than stresses. It has been shown that what is important in hybrid machining is not so much the height of the resulting irregularities and the effectiveness of their levelling by burnishing, but the geometry of the irregularities. After milling, surfaces with small, regular irregularities with smooth peaks and shallow valleys were found to be the best in tribological tests. Such roughness can be plastically levelled out during burnishing. On the basis of the experimental studies carried out, it was shown that a higher burnishing force does not always lead to higher wear resistance. Full article

Background/Objectives: Superficial esophageal cancer is diagnosed by evaluating the vascular architecture, including dilation, tortuosity, caliber change, and shape, of a lesion. However, this diagnosis is subjective and requires extensive experience. Endoscopically distinguishing squamous intraepithelial neoplasia (SIN) from esophageal cancer is difficult. Thus far, only a few studies have described the endoscopic findings of SIN. Therefore, the present study aimed to investigate whether endoscopic observation of the vascular architecture of tumors is useful in differentiating SIN from superficial esophageal cancer (SCC). Methods: This study included 141 patients who were histopathologically diagnosed with SIN or SCC between 2007 and 2023. Based on endoscopic images, patients were divided into those with a regular vascular arrangement (regular group) and those with an irregular vascular arrangement (irregular group). After evaluating the clinical characteristics, propensity score matching was used to assess the association between the groups and their pathological diagnoses. Results: Of the 141 patients, 44 and 97 were in the regular and irregular groups, respectively, with a ratio of 1:2. After propensity score matching, 33 and 66 patients were included in the regular and irregular groups, respectively. There were no significant differences between the groups after matching for age, alcohol consumption, smoking status, lesion site, sex, or lesion size. The regular group had significantly more patients with SIN, whereas the irregular group had significantly more patients with esophageal cancer (p < 0.001). Conclusions: The regularity of the vascular architecture may be useful for endoscopically distinguishing between SIN and esophageal cancer. Full article

Fractal dimension is a characteristic parameter used to measure the complexity and irregularity of geometric shapes and patterns. It is applied in architecture to explore complexity and irregularity and to assess the aesthetic preferences in architectural design. Office building facade design pattern, as an observation unit, has a positive connection with the aesthetic value. This study aims to evaluate facade design styles in terms of two aesthetic qualities, visual complexity and visual diversity, via applying fractal dimension to three design styles of office building facades in Erbil City. The study uses a combination of qualitative and quantitative evaluations to achieve this goal. It employs box-counting analysis through the ImageJ plugin to FracLac and the mathematical perplexity equation to evaluate visual complexity and diversity. The results indicate that the neo-classical office facade style, with a visual complexity value of 1.7008 and visual diversity of 21.27, presents an elevated level of aesthetics similar to the saccadic pattern facade. This study concluded that a neo-classical architectural style for office building facades is the most aesthetically preferable. Modern facade design is considered a secondary architectural style aimed at achieving aesthetic value. Ultimately, the high-tech style is the least attractive facade style. This study contributes to avoiding designs of unattractive office building facades due to a lack of architectural design vocabulary while avoiding overly complex designs that prove visually upsetting for viewers. Full article

The square steel tube–timber–concrete composite L-shaped columns are lighter in weight due to the inclusion of wood and exhibit superior seismic performance. This combination not only reduces transportation and labor costs but also enhances earthquake resistance. The wood contributes lightness and flexibility, the steel provides strength, and the concrete offers excellent compressive performance, thereby achieving an optimized design for performance. To investigate the axial compression performance of square steel tube–timber–concrete composite L-shaped short columns, axial compression tests were conducted on eight groups of L-shaped columns. The study examined ultimate load, failure modes, load–displacement relationships, initial stiffness, ductility, and bearing capacity improvement factors under different slenderness ratios, steel tube wall thicknesses, and wood content rates. The results show that the mechanical performance of the composite columns is excellent. Local buckling of the steel tube is the primary failure mode, with ‘bulging bands’ forming at the middle and ends. When the wood content reaches 25%, the synergy between the steel tube, concrete, and wood is optimal, significantly enhancing ductility and bearing capacity. The ductility of the specimen increased by 31.1%, and the bearing capacity increased by 4.14%. The bearing capacity increases with the steel tube wall thickness but decreases with increasing slenderness ratio. Additionally, based on the Mander principle and considering the partitioned constraint effects of concrete, a simplified calculation method for the axial compressive bearing capacity was proposed using the superposition principle. This method was validated to match well with the test results and can provide a reference for the design and application of these composite L-shaped columns. Full article

Improving carbon sink capacity is critical for meeting energy conservation and emission reduction targets, along with low-carbon development goals. Although many researchers have recognized that urban space can significantly influence the capacity of carbon sinks in urban areas, few studies have quantified the impact of urban landscape patterns, particularly urban green space (UGS) morphology, on carbon sinks. This study quantitatively investigated the impact of UGS morphology on carbon sinks using panel data from nine cities in the Guangdong–Hong Kong–Macao Greater Bay Area (GBA), China, from 2000 to 2017. A series of landscape metrics and land-use data was first selected to quantify the four dimensions of UGS: scale, compactness, type diversity, and shape complexity. Subsequently, the impact of UGS morphology on carbon sinks was estimated using a panel data model. The main findings were as follows. (1) From the carbon sink results, the carbon sink in the GBA was found to be in an evolutionarily stable state, reflecting the relatively limited potential for carbon enhancement in the region. (2) From the landscape metrics results, the AREA_MD was mainly distributed between 0.18 and 0.27. The AI was mainly distributed between 80 and 97, with a concentration at 90. The PAFRAC was mainly distributed between 1.39 and 1.43, with a concentration at 1.41. PR was mainly distributed between 6 and 7. There was a large disparity in the scale of UGS morphology between GBA cities, with an irregular and complex pattern that became more compact over time. (3) From the panel data results, the AI (p < 0.001) had a significant positive impact on carbon sinks, while PR (p < 0.001) had a significant negative impact. The more compact the UGS morphology, the greater the total carbon sink, and the more complex the UGS morphology, the smaller the total carbon sink. The findings highlighted the importance of urban planning and UGS morphological optimization for increasing carbon sink capacity, as well as providing policy makers and urban planners with theoretical references and guidance for achieving climate goals. Full article

Grasping objects of irregular shapes and various sizes remains a key challenge in the field of robotic grasping. This paper proposes a novel RGB-D data-based grasping pose prediction network, termed Cascaded Feature Fusion Grasping Network (CFFGN), designed for high-efficiency, lightweight, and rapid grasping pose estimation. The network employs innovative structural designs, including depth-wise separable convolutions to reduce parameters and enhance computational efficiency; convolutional block attention modules to augment the model’s ability to focus on key features; multi-scale dilated convolution to expand the receptive field and capture multi-scale information; and bidirectional feature pyramid modules to achieve effective fusion and information flow of features at different levels. In tests on the Cornell dataset, our network achieved grasping pose prediction at a speed of 66.7 frames per second, with accuracy rates of 98.6% and 96.9% for image-wise and object-wise splits, respectively. The experimental results show that our method achieves high-speed processing while maintaining high accuracy. In real-world robotic grasping experiments, our method also proved to be effective, achieving an average grasping success rate of 95.6% on a robot equipped with parallel grippers. Full article