Breast cancer (BC) diagnosis and treatment rely heavily on molecular markers such as HER2, Ki67, PR, and ER. Currently, these markers are identified by invasive methods.
This meta-analysis ...investigates the diagnostic accuracy of ultrasound-based radiomics as a novel approach to predicting these markers.
A comprehensive search of PubMed, EMBASE, and Web of Science databases was conducted to identify studies evaluating ultrasound-based radiomics in BC. Inclusion criteria encompassed research on HER2, Ki67, PR, and ER as key molecular markers. Quality assessment using Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) and Radiomics Quality Score (RQS) was performed. The data extraction step was performed systematically.
Our meta-analysis quantifies the diagnostic accuracy of ultrasound-based radiomics with a sensitivity and specificity of 0.76 and 0.78 for predicting HER2, 0.80, and 0.76 for Ki67 biomarkers. Studies did not provide sufficient data for quantitative PR and ER prediction analysis. The overall quality of studies based on the RQS tool was moderate. The QUADAS-2 evaluation showed that the studies had an unclear risk of bias regarding the flow and timing domain.
Our analysis indicated that AI models have a promising accuracy for predicting key molecular biomarkers' status in BC patients. We performed the quantitative analysis for HER2 and Ki67 biomarkers which yielded a moderate to high accuracy. However, studies did not provide adequate data for meta-analysis of ER and PR prediction accuracy of developed models. The overall quality of the studies was acceptable. In future research, studies need to report the results thoroughly. Also, we suggest more prospective studies from different centers.
Emerging evidence suggests that microRNAs (miRs) are associated with the progression of osteoarthritis (OA). In this study, the role of exosomal miR-136-5p derived from mesenchymal stem cells (MSCs) ...in OA progression is investigated and the potential therapeutic mechanism explored.
Bone marrow mesenchymal stem cells (BMMSCs) and their exosomes were isolated from patients and identified. The endocytosis of chondrocytes and the effects of exosome miR-136-5p on cartilage degradation were observed and examined by immunofluorescence and cartilage staining. Then, the targeting relationship between miR-136-5p and E74-like factor 3 (ELF3) was analyzed by dual-luciferase report assay. Based on gain- or loss-of-function experiments, the effects of exosomes and exosomal miR-136-5p on chondrocyte migration were examined by EdU and Transwell assay. Finally, a mouse model of post-traumatic OA was developed to evaluate effects of miR-136-5p on chondrocyte degeneration in vivo.
In the clinical samples of traumatic OA cartilage tissues, we detected increased ELF3 expression, and reduced miR-136-5p expression was determined. The BMMSC-derived exosomes showed an enriched level of miR-136-5p, which could be internalized by chondrocytes. The migration of chondrocyte was promoted by miR-136-5p, while collagen II, aggrecan, and SOX9 expression was increased and MMP-13 expression was reduced. miR-136-5p was verified to target ELF3 and could downregulate its expression. Moreover, the expression of ELF3 was reduced in chondrocytes after internalization of exosomes. In the mouse model of post-traumatic OA, exosomal miR-136-5p was found to reduce the degeneration of cartilage extracellular matrix.
These data provide evidence that BMMSC-derived exosomal miR-136-5p could promote chondrocyte migration in vitro and inhibit cartilage degeneration in vivo, thereby inhibiting OA pathology, which highlighted the transfer of exosomal miR-136-5p as a promising therapeutic strategy for patients with OA.
Over the past three decades, the numerical manifold method (NMM) has attracted many researchers from geotechnical community because it unifies the solutions of continuous and discontinuous problems ...in the same framework. However, due to the lack of ready-made preprocessing tools, the development of three dimensional NMM (3DNMM) is still limited. A practical strategy to generate the discretized models for a 3DNMM analysis is proposed. In the proposed strategy, regular hexahedral meshes are uniformly deployed to construct the mathematical cover system. The physical meshes including the joints, material interfaces, and problem domain boundaries are adopted to cut the mathematical cover system into physical cover system and manifold elements (MEs). To improve the efficiency of the proposed strategy, the Intel threading building blocks (TBB) parallel library for CPU paralleling is adopted. Several typical examples are adopted to validate the proposed strategy. The results show that the proposed strategy can effectively generate the discretized 3D models of some geotechnical problems for 3DNMM calculations. The proposed strategy deserves a further investigation.
A three-dimensional numerical model was developed to investigate effects of laser scanning speed, laser power, and hatch spacing on the thermodynamic behaviors of the molten pool during selective ...laser melting of AlSi10Mg powder. A randomly distributed packed powder bed was achieved using discrete element method (DEM). The powder bed can be treated as a porous media with interconnected voids in the simulation. A good agreement between numerical results and experimental results establish the validity of adopted method. The numerical results show that the Marangoni flow within the molten pool was significantly affected by the processing parameters. An intense Marangoni flow leads to a perturbation within the molten pool. In addition, a relatively high scanning speed tends to cause melt instability. The perturbation or the instability within the molten pool results in the formation of pores during SLM, which have a direct influence on the densification level.
•We simulate the slow spin-up of Didymos using rubble-pile models with different material and internal configurations.•The failure mode of a rubble pile depends mainly on the arrangement and size ...distribution of its constituent particles.•The Didymos primary in certain configurations can remain geo-statically stable at a bulk density≳2.4g/cc without requiring cohesion.
As the target of the proposed Asteroid Impact & Deflection Assessment (AIDA) mission, the near-Earth binary asteroid 65803 Didymos represents a special class of binary asteroids, those whose primaries are at risk of rotational disruption. To gain a better understanding of these binary systems and to support the AIDA mission, this paper investigates the creep stability of the Didymos primary by representing it as a cohesionless self-gravitating granular aggregate subject to rotational acceleration. To achieve this goal, a soft-sphere discrete element model (SSDEM) capable of simulating granular systems in quasi-static states is implemented and a quasi-static spin-up procedure is carried out. We devise three critical spin limits for the simulated aggregates to indicate their critical states triggered by reshaping and surface shedding, internal structural deformation, and shear failure, respectively. The failure condition and mode, and shear strength of an aggregate can all be inferred from the three critical spin limits. The effects of arrangement and size distribution of constituent particles, bulk density, spin-up path, and interparticle friction are numerically explored. The results show that the shear strength of a spinning self-gravitating aggregate depends strongly on both its internal configuration and material parameters, while its failure mode and mechanism are mainly affected by its internal configuration. Additionally, this study provides some constraints on the possible physical properties of the Didymos primary based on observational data and proposes a plausible formation mechanism for this binary system. With a bulk density consistent with observational uncertainty and close to the maximum density allowed for the asteroid, the Didymos primary in certain configurations can remain geo-statically stable without requiring cohesion.
Considering the characteristics of complex texture backgrounds, uneven brightness, varying defect sizes, and multiple defect types of the bearing surface images, a surface defect detection method for ...bearing rings is proposed based on improved YOLOv5. First, replacing the C3 module in the backbone network with a C2f module can effectively reduce the number of network parameters and computational complexity, thereby improving the speed and accuracy of the backbone network. Second, adding the SPD module into the backbone and neck networks enhances their ability to process low-resolution and small-object images. Next, replacing the nearest-neighbor upsampling with the lightweight and universal CARAFE operator fully utilizes feature semantic information, enriches contextual information, and reduces information loss during transmission, thereby effectively improving the model’s diversity and robustness. Finally, we constructed a dataset of bearing ring surface images collected from industrial sites and conducted numerous experiments based on this dataset. Experimental results show that the mean average precision (mAP) of the network is 97.3%, especially for dents and black spot defects, improved by 2.2% and 3.9%, respectively, and that the detection speed can reach 100 frames per second (FPS). Compared with mainstream surface defect detection algorithms, the proposed method shows significant improvements in both accuracy and detection time and can meet the requirements of industrial defect detection.
Asteroids in mean motion resonances with giant planets are common in the solar system, but it was not until recently that several asteroids in retrograde mean motion resonances with Jupiter and ...Saturn were discovered. A retrograde co-orbital asteroid of Jupiter, 2015 BZ509 is confirmed to be in a long-term stable retrograde 1:1 mean motion resonance with Jupiter, which gives rise to our interests in its unique resonant dynamics. In this paper, we investigate the phase-space structure of the retrograde 1:1 resonance in detail within the framework of the circular restricted three-body problem. We construct a simple integrable approximation for the planar retrograde resonance using canonical contact transformation and numerically employ the averaging procedure in closed form. The phase portrait of the retrograde 1:1 resonance is depicted with the level curves of the averaged Hamiltonian. We thoroughly analyze all possible librations in the co-orbital region and uncover a new apocentric libration for the retrograde 1:1 resonance inside the planet's orbit. We also observe the significant jumps in orbital elements for outer and inner apocentric librations, which are caused by close encounters with the perturber.
We study the orbits and manifolds near the equilibrium points of a rotating asteroid. The linearised equations of motion relative to the equilibrium points in the gravitational field of a rotating ...asteroid, the characteristic equation and the stable conditions of the equilibrium points are derived and discussed. First, a new metric is presented to link the orbit and the geodesic of the smooth manifold. Then, using the eigenvalues of the characteristic equation, the equilibrium points are classified into 8 cases. A theorem is presented and proved to describe the structure of the submanifold as well as the stable and unstable behaviours of a massless test particle near the equilibrium points. The linearly stable, the non-resonant unstable, and the resonant equilibrium points are discussed. There are three families of periodic orbits and four families of quasi-periodic orbits near the linearly stable equilibrium point. For the non-resonant unstable equilibrium points, there are four relevant cases; for the periodic orbit and the quasi-periodic orbit, the structures of the submanifold and the subspace near the equilibrium points are studied for each case. For the resonant equilibrium points, the dimension of the resonant manifold is greater than 4, and we find at least one family of periodic orbits near the resonant equilibrium points. As an application of the theory developed here, we study relevant orbits for the asteroids 216 Kleopatra, 1620 Geographos, 4769 Castalia and 6489 Golevka.
Due to the nonlinear saturated hysteretic behavior of SMA during the phase transformation, it is not easy to achieve accurate position tracking control by establishing an effective controller for the ...SMA actuator system. In this paper, an accurate position control method based on fuzzy time delay algorithms for a soft robot is proposed. The error of TDE is unavoidable because the smallest value for the time delay is the sampling time of the microcontroller, a rule-based fuzzy logic controller for online gain tuning combined with TDC is proposed to eliminate the position control errors. Three different sets of experiments are conducted, using step, sine and ramp signals as reference inputs. The experimental results demonstrate that the proposed method has the smallest steady state error and the least overshoot than TDE and PI controller. In conclusion, the proposed method should be a viable alternative for position control of SMA actuator.
Introduction
Recent studies have indicated the potential of stem cell therapy in combination with cytokines to restore the bone repair via migration and homing of stem cells to the defected area. The ...present study aimed to investigate the mobilization and recruitment of mesenchymal stem cells (MSCs) in response to SDF-1.
Materials and Methods
Herein, the knockout rat model of the bone defect (BD) was treated with the induced membrane technique. Then, wild type Wistar rats and SDF-1-knockout rats were selected for the establishment of BD-induced membrane (BD-IM) models and bone-graft (BG) models. The number of MSCs was evaluated by flow cytometry, along with the expression pattern of the SDF-1/CXCR4 axis as well as osteogenic factors was identified by RT-qPCR and Western blot analyses. Finally, the MSC migration ability was assessed by the Transwell assay.
Results
Our data illustrated that in the induced membrane tissues, the number of MSCs among the BD-IM modeled rats was increased, whereas, a lower number was documented among BG modeled rats. Besides, we found that lentivirus-mediated over-expression of SDF-1 in BG modeled rats could activate the SDF-1/CXCR4 axis, mobilize MSCs into the defect area, and up-regulate the osteogenic proteins.
Conclusions
Collectively, our study speculated that up-regulation of SDF-1 promotes the mobilization and migration of MSCs through the activation of the SDF-1/CXCR4 signal pathway.
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