Exploiting Counter-Examples for Active Learning with Partial labels

This paper studies a new problem, \emph{active learning with partial labels} (ALPL). In this setting, an oracle annotates the query samples with partial labels, relaxing the oracle from the demanding accurate labeling process. To address ALPL, we first build an intuitive baseline that can be seamlessly incorporated into existing AL frameworks. Though effective, this baseline is still susceptible to the \emph{overfitting}, and falls short of the representative partial-label-based samples during the query process. Drawing inspiration from human inference in cognitive science, where accurate inferences can be explicitly derived from \emph{counter-examples} (CEs), our objective is to leverage this human-like learning pattern to tackle the \emph{overfitting} while enhancing the process of selecting representative samples in ALPL. Specifically, we construct CEs by reversing the partial labels for each instance, and then we propose a simple but effective WorseNet to directly learn from this complementary pattern. By leveraging the distribution gap between WorseNet and the predictor, this adversarial evaluation manner could enhance both the performance of the predictor itself and the sample selection process, allowing the predictor to capture more accurate patterns in the data. Experimental results on five real-world datasets and four benchmark datasets show that our proposed method achieves comprehensive improvements over ten representative AL frameworks, highlighting the superiority of WorseNet. The source code will be available at \url{https://github.com/Ferenas/APLL}.Comment: 29 pages, Under revie

Minimal information for studies of extracellular vesicles (MISEV2023): From basic to advanced approaches

Extracellular vesicles (EVs), through their complex cargo, can reflect the state of their cell of origin and change the functions and phenotypes of other cells. These features indicate strong biomarker and therapeutic potential and have generated broad interest, as evidenced by the steady year-on-year increase in the numbers of scientific publications about EVs. Important advances have been made in EV metrology and in understanding and applying EV biology. However, hurdles remain to realising the potential of EVs in domains ranging from basic biology to clinical applications due to challenges in EV nomenclature, separation from non-vesicular extracellular particles, characterisation and functional studies. To address the challenges and opportunities in this rapidly evolving field, the International Society for Extracellular Vesicles (ISEV) updates its 'Minimal Information for Studies of Extracellular Vesicles', which was first published in 2014 and then in 2018 as MISEV2014 and MISEV2018, respectively. The goal of the current document, MISEV2023, is to provide researchers with an updated snapshot of available approaches and their advantages and limitations for production, separation and characterisation of EVs from multiple sources, including cell culture, body fluids and solid tissues. In addition to presenting the latest state of the art in basic principles of EV research, this document also covers advanced techniques and approaches that are currently expanding the boundaries of the field. MISEV2023 also includes new sections on EV release and uptake and a brief discussion of in vivo approaches to study EVs. Compiling feedback from ISEV expert task forces and more than 1000 researchers, this document conveys the current state of EV research to facilitate robust scientific discoveries and move the field forward even more rapidly

Process Optimization for Up-Facing Surface Finish of AlSi10Mg Alloy Produced by Laser Powder Bed Fusion

This work investigates the effects of various processing parameters (laser power, scanning speed, hatch distance and beam offset) on the resultant inclined up-facing surface roughness of AlSi10Mg alloys produced by laser powder bed fusion (LPBF). A two-step approach, orthogonal test followed by the Doehlert matrix design (DMD) test is used to efficiently optimize the up-facing surface and contour parameters. The former method aims to determine the significance of variables while the latter one facilitates a rapid optimization. The results show that the interaction and interdependency among the parameters are of great significance to the obtainable surface roughness. Using a rational design of experiments, the optimized up-facing surface roughness of Ra of 5.4 μm is achieved. This is attributed to the elimination of the laser partition track and the reduction in irregularities at the edges of the parts. This work demonstrates an effective approach of experimental processing parameter optimization to improve the surface finish of LPBF parts

Process Optimization for Up-Facing Surface Finish of AlSi10Mg Alloy Produced by Laser Powder Bed Fusion

This work investigates the effects of various processing parameters (laser power, scanning speed, hatch distance and beam offset) on the resultant inclined up-facing surface roughness of AlSi10Mg alloys produced by laser powder bed fusion (LPBF). A two-step approach, orthogonal test followed by the Doehlert matrix design (DMD) test is used to efficiently optimize the up-facing surface and contour parameters. The former method aims to determine the significance of variables while the latter one facilitates a rapid optimization. The results show that the interaction and interdependency among the parameters are of great significance to the obtainable surface roughness. Using a rational design of experiments, the optimized up-facing surface roughness of Ra of 5.4 μm is achieved. This is attributed to the elimination of the laser partition track and the reduction in irregularities at the edges of the parts. This work demonstrates an effective approach of experimental processing parameter optimization to improve the surface finish of LPBF parts

Interaction between Corneal and Internal Ocular Aberrations Induced by Orthokeratology and Its Influential Factors

Purpose. To investigate the interaction between corneal, internal, and total wavefront aberrations (WAs) and their influential factors during orthokeratology (OK) treatment in Chinese adolescents. Methods. Thirty teenagers (n=30 eyes) were enrolled in the study; spherical equivalent refraction (SE), corneal curvature radius (CCR), central corneal thickness (CCT), WAs, and the difference in limbal transverse diameter and OK lens diameter (ΔLLD) were detected before and after one-month OK treatment. Every component of WAs was measured simultaneously by iTrace aberrometer. The influential factors of OK-induced WAs were analyzed. Results. SE and CCT decreased while CCR increased significantly (P<0.01). Higher-order aberrations (HOAs), Spherical aberrations (SAs), and coma increased significantly (P<0.01). Corneal horizontal coma (Z31-C) and corneal spherical aberrations (Z40-C) increased (P<0.01). The HOAs, coma, SAs, Z31-C, Z31-T, Z40-C, and Z40-T were positively correlated with SE and CCR (P<0.01). Z3−1-C showed negative correlations with (ΔLLD) and positive correlations with SE (P<0.05). Conclusions. The increase in OK-induced HOAs is mainly attributed to Z31 and Z40 of cornea. Z3−1 in the internal component showed a compensative effect on the corneal vertical coma. The degree of myopic correction and increase in CCR may be the essential influential factors of the increase in Z31 and Z40. The appropriate size of the OK lens may be helpful to decrease OK-induced vertical coma

Interaction between Corneal and Internal Ocular Aberrations Induced by Orthokeratology and Its Influential Factors

Purpose. To investigate the interaction between corneal, internal, and total wavefront aberrations (WAs) and their influential factors during orthokeratology (OK) treatment in Chinese adolescents. Methods. Thirty teenagers (n=30 eyes) were enrolled in the study; spherical equivalent refraction (SE), corneal curvature radius (CCR), central corneal thickness (CCT), WAs, and the difference in limbal transverse diameter and OK lens diameter (ΔLLD) were detected before and after one-month OK treatment. Every component of WAs was measured simultaneously by iTrace aberrometer. The influential factors of OK-induced WAs were analyzed. Results. SE and CCT decreased while CCR increased significantly (P<0.01). Higher-order aberrations (HOAs), Spherical aberrations (SAs), and coma increased significantly (P<0.01). Corneal horizontal coma (Z31-C) and corneal spherical aberrations (Z40-C) increased (P<0.01). The HOAs, coma, SAs, Z31-C, Z31-T, Z40-C, and Z40-T were positively correlated with SE and CCR (P<0.01). Z3−1-C showed negative correlations with (ΔLLD) and positive correlations with SE (P<0.05). Conclusions. The increase in OK-induced HOAs is mainly attributed to Z31 and Z40 of cornea. Z3−1 in the internal component showed a compensative effect on the corneal vertical coma. The degree of myopic correction and increase in CCR may be the essential influential factors of the increase in Z31 and Z40. The appropriate size of the OK lens may be helpful to decrease OK-induced vertical coma

The Influence of Structural Design on the Dimensional Accuracy of CuCrZr Alloy Produced by Laser Powder Bed Fusion

With the upgrade of additive manufacturing (AM) equipment, pure copper and various Cu-based alloys with almost full density have been successfully produced, maintaining their excellent thermal and electrical conductivity and good mechanical properties at high temperatures as well. In this paper, a model with a series of inclined surface structures was designed and fabricated to investigate the structural design on the formability of CuCrZr alloy produced by laser powder bed fusion (LPBF). The typical structure dimensions of the as-built samples were measured and compared with their corresponding dimensions and the inclined angle (α) and the relative angle (γ) between the inclined surface and recoating directions. The results demonstrate that the inclined structures with α Ld) between the typical structure dimensions and their models increase with the decreasing of α. It has been observed that Ld reaches 1 mm when α is 20° and drastically reduces to around 200 μm when α is above 50°. When α Ld is generally increasing with a rising γ value from 0° to 180°, significantly affecting the dimensional accuracy

Mechanical properties and energy absorption capabilities of plate-based AlSi10Mg metamaterials produced by laser powder bed fusion

Plate-based lattice structures are an emerging category of mechanical metamaterials with exceptional mechanical performance. In this work, plate-based SCFCC metamaterials of AlSi10Mg with various relative densities are fabricated by laser powder bed fusion (LPBF). Circular holes are strategically designed and placed at the center of each non-load-bearing face for residual powder removal. Quasi-static compression experiments and numerical simulations are performed to investigate their mechanical performance and deformation mechanisms. Results indicate that the elastic modulus of SCFCC metamaterials decreases by 3.5% with the presence of 0.9 mm diameter holes, while increasing the hole size shows negligible impact on the elastic modulus. The novel plate-based SCFCC structure exhibits superior mechanical properties and enhanced energy absorption capacity concerning conventional high-stiffness truss-based and shell-based counterparts. The improvement, at the relative density of 0.2, can be observed in terms of elastic modulus (around 50%), peak compressive strength (around 300%), energy absorption capacity (around 400% or 200%). When increasing the relative density from 0.2 to 0.5, plate-based SCFCC metamaterial still maintains superior mechanical performance while the gaps between SCFCC and its counterparts narrow down gradually owing to the loss of structural features. Moreover, mechanical characteristics and coefficients of three Gibson and Ashby analytical equations are determined. This work proposes a novel type of plate-based structure with both exceptional mechanical performance and good additive manufacturability, which opens a new avenue for the design of lightweight mechanical metamaterials