Actual Magnification Research Articles

Hagnifinder: Recovering magnification information of digital histological images using deep learning

Background and objectiveTraining a robust cancer diagnostic or prognostic artificial intelligent model using histology images requires a large number of representative cases with labels or annotations, which are difficult to obtain. The histology snapshots available in published papers or case reports can be used to enrich the training dataset. However, the magnifications of these invaluable snapshots are generally unknown, which limits their usage. Therefore, a robust magnification predictor is required for utilizing those diverse snapshot repositories consisting of different diseases. This paper presents a magnification prediction model named Hagnifinder for H&E-stained histological images. MethodsHagnifinder is a regression model based on a modified convolutional neural network (CNN) that contains 3 modules: Feature Extraction Module, Regression Module, and Adaptive Scaling Module (ASM). In the training phase, the Feature Extraction Module first extracts the image features. Secondly, the ASM is proposed to address the learned feature values uneven distribution problem. Finally, the Regression Module estimates the mapping between the regularized extracted features and the magnifications. We construct a new dataset for training a robust model, named Hagni40, consisting of 94 643 H&E-stained histology image patches at 40 different magnifications of 13 types of cancer based on The Cancer Genome Atlas. To verify the performance of the Hagnifinder, we measure the accuracy of the predictions by setting the maximum allowable difference values (0.5, 1, and 5) between the predicted magnification and the actual magnification. We compare Hagnifinder with state-of-the-art methods on a public dataset BreakHis and the Hagni40. ResultsThe Hagnifinder provides consistent prediction accuracy, with a mean accuracy of 98.9%, across 40 different magnifications and 13 different cancer types when Resnet50 is used as the feature extractor. Compared with the state-of-the-art methods focusing on 4–5 levels of magnification classification, the Hagnifinder achieves the best and most comparable performance in the BreakHis and Hagni40 datasets. ConclusionsThe experimental results suggest that Hagnifinder can be a valuable tool for predicting the associated magnification of any given histology image.

Gravitational wave interference via gravitational lensing: Measurements of luminosity distance, lens mass, and cosmological parameters

The gravitational lensing of gravitational waves might cause beat patterns detectable by interferometers. The feature of this kind of signal is the existence of the beat pattern in the early inspiral phase, followed by a seemingly randomly changing profile. After the strain peaks for the first time, the signal takes the usual waveform and the strain peaks for the second time. Once this signal is detected, the actual magnification factors can be obtained, so the true luminosity distance of the binary system is known. If the lens can be described by a point mass or a singular isothermal sphere, the functional forms of the time delay and the magnification factors are simple enough, so we can infer the mass of the lens or the cosmological parameters.

Research on three-stage amplified compliant mechanism-based piezo-driven microgripper

The microgripper based on the principle of lever amplification is easy to realize; however, the theoretical amplification factor is limited by the space size and the structure is not compact enough. The microgripper based on the triangular amplification principle has a compact structure and high amplification factor, but it is not conducive to miniaturization design. Considering compactness, parallel clamping, high magnification, and miniaturization design, a three-stage amplifier consisting of a semi-rhombic amplifier and lever amplifiers is designed. To begin with, the theoretical amplification ratio and the relationship between input variables and output variables are calculated by energy method. Furthermore, the finite element analysis software is used to optimize the structural parameters and analyze the performance of the model. Lastly, the experimental verification is carried out. At 150 V of driving voltage, the maximum output displacement was 530mm, and the actual magnification was 24 times. Microparts can be gripped in parallel and stably, which confirms the validity of the design.

Design of large-displacement asymmetric piezoelectric microgripper based on flexible mechanisms

The output displacement of the traditional symmetrical microgripper is large, but its micro-components or parts are easily damaged due to the uneven force exerted on the left and right jaws of the gripper. The output force of the traditional asymmetric microgripper is stable. However, its output displacement is small, typically half the output displacement of the symmetric microgripper. To solve these problems, in this study, we designed a large-displacement asymmetric microgripper. First, we calculated the relationship between the theoretical input and output variables based on their geometric relationship. Then, we analyzed the performance of the microgripper using finite element software. Lastly, we used a piezoelectric actuator as the input driver of the microgripper. The errors associated with the theoretical and simulated output displacements were 7.05% and 9.24%, respectively. At 150 V of driving voltage, the maximum output displacement was 224 µm, and the actual magnification was 11.2 times. Microparts can be gripped in parallel and stably, which confirms the validity of the design.

Design of a flexible piezoelectric microgripper based on combined amplification principles

Aiming to address the problem of the low amplification ratio of traditional microgrippers, a two-stage microgripper based on the principle of combined amplification was designed with a high amplification ratio and large displacement, using a simple and compact structure. The relationship between theoretical input variables and output variables were first calculated by a projection theorem. Secondly, the performance of the microgripper was analyzed by finite element analysis (FEA). Finally, the accuracy of the theoretical calculation and FEA was verified experimentally. The results show that the microgripper has high magnification and can be gripped in parallel, with self-adaptability for many irregular shaped micro objects. The actual magnification was 23.2×, which is greater than similar products.

Study on the Calculated and Actual Magnification of Optical Aids for Low Vision Rehabilitation

Study on the Calculated and Actual Magnification of Optical Aids for Low Vision Rehabilitation

Decreased Thickness and Integrity of the Macular Elastic Layer of Bruch's Membrane Correspond to the Distribution of Lesions Associated with Age-Related Macular Degeneration

Age-related macular degeneration (AMD) is a leading cause of blindness in the elderly. In its severest form, choroidal neovessels breach the macular Bruch's membrane, an extracellular matrix compartment comprised of elastin and collagen laminae, and grow into the retina. We sought to determine whether structural properties of the elastic lamina (EL) correspond to the region of the macula that is predilected toward degeneration in AMD. Morphometric assessment of the macular and extramacular regions of 121 human donor eyes, with and without AMD, revealed a statistically significant difference in both the integrity (P < 0.0001) and thickness (P < 0.0001) of the EL between the macular and extramacular regions in donors of all ages. The EL was three to six times thinner and two to five times less abundant in the macula than in the periphery. The integrity of the macular EL was significantly lower in donors with early-stage AMD (P = 0.028), active choroidal neovascularization (P = 0.020), and disciform scars (P = 0.003), as compared to unaffected, age-matched controls. EL thickness was significantly lower only in individuals with disciform scars (P = 0.008). The largest gaps in macular EL integrity were significantly larger in all categories of AMD (each P < 0.0001), as compared to controls. EL integrity, thickness, and gap length in donors with geographic atrophy did not differ from those of controls. These structural properties of the macular EL correspond spatially to the distribution of macular lesions associated with AMD and may help to explain why the macula is more susceptible to degenerative events that occur in this disease.

Dutch Holographic Laboratory

My company, Dutch Holographic Laboratory B.V. (DHL), first received international recognition with Microscope in 1984. This image of a microscope protrudes more than 9 inches in front of the holographic plate. When viewers look into the microscope's illusory eyepiece, they see the actual magnification of a computer chip, just as if the microscope really existed. This 8-x-10-in reflection hologram has opened viewers' eyes to a new perception of holographic imaging and spawned a number of offshoots (Fig. 1). DHL's laboratories, which include high-tech laser systems, are dedicated to ongoing research and development in holography. Apart from the lasers and optics, all the equipment is custom-fabricated in house and includes four vibration-isola-

Preoperative planning for total hip arthroplasty: Quantitating its utility and precision

This study evaluated the usefulness and accuracy of preoperative planning for cemented and cementless total hip arthroplasty (THA). The authors conducted a prospective study of 110 consecutive primary cases in which surgeons recorded the preoperative plan and what occurred in each case. Measured variables included estimated magnification, acetabular cup and femoral stem size, planned lengthening, and anticipated problems. Preoperative estimates of magnification frequently differed from actual magnification, and in 17% of cases it affected choice of implant size. Preoperative bone morphology did not correlate with type of femoral stem fixation. Implant sizing was predicted from the preoperative plan for 62% of acetabular cups, 78% of cemented stems, and 42% of the cementless stems. Leg-length equalization was a goal in only 70% of cases. Anticipated problems focused on anatomic variations, but intraoperative problems involved technique and equipment. The authors conclude that surgeons need better methods to estimate magnification and bone morphology from preoperative radiographs. Preoperative planning may not reduce intraoperative complications, which can arise from unanticipated technique and equipment mishaps.

A Computer-Based System for Measurements and Analyses in Radiology

A computer-based system for direct measurements on images and for analyses of data is presented. Distances, angles, and areas are measured on a backlighted digitizer table. Calibration corrects for actual magnification. Data are analyzed and compared to normal values by a microcomputer. The system is precise and time saving.

Digital Display of Lens Current For Accurate Calibration of the Electron Microscope

During normal operation a 5-10% variation is reasonable to expect between the magnification readout on the instrument and the actual magnification at the image plane. An error of this magnitude becomes ntenable when either precise comparative dimensions are necessary, or when undertaking stereology studies. In some instances, it is possible to obtain the required degree of accuracy on the basis of relative dimensions. Accurate stereology studies require for each set of samples precise magnificatipn calibration which is generally done by repeating a calibration for each set of samples. An alternative approach involves quantitative monitoring of the lens current separately for each of the objective, intermediate, and projector lenses with a digital milliampere meter.