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With the fast development of modern microscopes and bioimaging techniques, an unprecedentedly large amount of imaging data is being generated, stored, analyzed, and shared through networks. The size of the data poses great challenges for current data infrastructure. One common way to reduce the data size is by image compression. This study analyzes multiple classic and deep-learning-based image compression methods, as well as an empirical study on their impact on downstream deep-learning-based image processing models. We used deep-learning-based label-free prediction models (i.e., predicting fluorescent images from bright-field images) as an example downstream task for the comparison and analysis of the impact of image compression. Different compression techniques are compared in compression ratio, image similarity, and, most importantly, the prediction accuracy of label-free models on original and compressed images. We found that artificial intelligence (AI)-based compression techniques largely outperform the classic ones with minimal influence on the downstream 2D label-free tasks. In the end, we hope this study could shed light on the potential of deep-learning-based image compression and raise the awareness of the potential impacts of image compression on downstream deep-learning models for analysis.
Inertial Confinement Fusion (ICF) recently became the first technology to achieve ignition of hydrogen nuclear fusion fuel in the laboratory. Unlike magnetically confined fusion plasmas such as tokamaks, ICF requires high fuel compression. This implies a high convergence and high velocity implosion, usually driven with laser beams. This allows hydrodynamic instabilities to develop, primarily RTI and RMI. During the initial shock and acceleration phase when the shell is brought up to the peak implosion velocity, RMI instabilities at the various interfaces are followed by ablation front RT growth as the low-density plasma accelerates the dense shell of solid ablator and fuel. The implosion deceleration at the center is also unstable. The resulting spikes and bubbles prevent efficient fuel compression, and can also inject contaminants. I will discuss the measurement and mitigation of this problem. Z-pinch machines, which instead use an electrical current to compress the plasma, will illustrate the role of MHD in the ICF application.
The possible physical and chemical forces controlling the volume change behavior of kaolinite were ascertained from the sediment volume of kaolinite in various solvents under no external load condition and from conventional oedometer measurements of kaolinite in several pore fluids. The minimum sediment volume of 14.5 cm3/10 g clay occupied by kaolinite in water where repulsive (R) forces were dominant indicated that the R contribution was insignificant for kaolinite. The maximum sediment volume of 25.0 cm3/10 g clay in benzene where coulombic attraction forces were significant suggested that electrostatic attraction between silicate sheets and midplane cations and van der Waals forces were not appreciable for kaolinite. The positive edge-negative face bonding of kaolinite particles in benzene was unlikely because the protons required to impart a positive charge to the edges were not available in the nonpolar solvent. The 3688 cm−1 band in the infrared spectrum of a kaolinite-dimethylamine sample decreased by 10 cm−1 on H-bond formation of the solvent molecule with the exposed structural hydroxyls of the octahedral sheet. The adsorbed solvent molecules likely H-bonded with an adjacent clay particle. That such interparticle H-bonds controlled the sediment volume and interparticle attraction in kaolinite was indicated by the decrease in sediment volume with increase in dipole moment of the solvent molecule, i.e., 25.0 cm3/10 g clay in n-heptane (dipole moment, μ = 0), 23.5 cm3/10 g clay in toluene (μ = 0.36), 17.0 cm3/10 g clay in ethanol (μ = 1.67), and 14.5 cm3/10 g clay in water (μ = 1.84).
In the oedometer tests with various pore fluids, a high void ratio (i.e., volume of voids/volume of solids) of ≈ 1.3 was obtained for kaolinite in n-heptane, and hexane (μ ≅ 0) at an external pressure of 1 kg/cm2 probably because the weakly bonded kaolinite particles were randomly oriented. At the corresponding applied pressure a lower void ratio of 0.88 resulted in water (μ = 1.84) where the stronger hydrogen bond between flat layer surfaces of adjacent particles favored a parallel orientation of clay particles.
The variations in void ratio-external pressure relationship indicated that kaolinite underwent lower compressibility in a solvent with low dipole moment and vice versa. Thus, the interparticle H-bond did not play a significant role in controlling the shear resistance and volume change behavior. The volume change behavior was essentially controlled by frictional forces and clay fabric. In nonpolar solvents the random arrangement of kaolinite particles and the frictional forces mobilized a high shear resistance on the application of a consolidation pressure, resulting in a lower compressibility. In a solvent with high dipole moment the parallel array of clay particles mobilized less shear resistance and produced a greater compression.
This chapter presents a comprehensive overview of the mechanical behavior of Network materials, with emphasis on the structure–properties relation. Crosslinked and non-crosslinked Network materials are discussed in separate sections. The behavior of crosslinked networks in tension, shear, compression, and multiaxial loading is described. The effects of fiber tortuosity, fiber alignment, crosslink compliance, network connectivity, and variability of fiber properties on network stiffness and nonlinear behavior are discussed in detail. The size effect on linear and nonlinear material properties is evaluated in relation with network parameters. Three types of nonlinear behavior are identified, corresponding to networks that stiffen or soften continuously during deformation, and networks with an approximately linear response. Numerous examples of each type are presented, including collagen networks, fibrin and actin gels, elastomers, paper, and nonwovens. The response of non-crosslinked athermal networks, such as fiber wads, is studied in compression and tension. The effect of entanglements in athermal networks is analyzed and a parallel drawn with the mechanics of thermoplastics.
From any two median spaces $X$ and $Y$, we construct a new median space $X \circledast Y$, referred to as the diadem product of $X$ and $Y$, and we show that this construction is compatible with wreath products in the following sense: given two finitely generated groups $G,\,H$ and two (equivariant) coarse embeddings into median spaces $X,\,Y$, there exist a(n equivariant) coarse embedding $G\wr H \to X \circledast Y$. The construction offers a unified point of view on various questions related to the Hilbertian geometry of wreath products of groups.
A system for examination of the peripheral nerves of the upper limb is described in this chapter. This includes the ulnar, median, radial, axillary and musculocutaneous nerves. The steps are inspection followed by a screen test to decide if the lesion is likely to be radial, median or ulnar. Then the nerve is examined in more detail by testing sensation and movement in relation to that nerve. Provocation tests are performed if necessary. This chapter also describes nerve compression as a result of thoracic outlet syndrome, as this may be a differential diagnosis. In the ‘Advanced corner’ Tinel’s sign and Valleix phenomenon as well as ‘double crush’ are described.
Elephant seals lead two entirely different lives: one on land and one at sea. The adaptations for feeding at sea, such as blubber for warmth in cold waters, streamlining to reduce drag, and a source of energy to see them through long fasts, impose difficulties on land. It is costly to move their large bodies quickly for any distance on land. Their blubber layer is like a puffy coat that causes overheating on hot days on land. The loss of feet for flippers leaves them vulnerable to fast-moving and agile terrestrial carnivores, which partially explains their historical preferences to breed on islands devoid of bears, wolves, and coyotes. The evolutionary changes in their bodies must be a compromise between what is necessary for successful foraging at sea and breeding and molting on land. For example, elephant seals hold their breath while sleeping on land and during dives at sea.
This is a preliminary text introducing the terminology, basic concepts and tools for the next chapters. It reflects six main streams in the area. At the beginning some basic combinatorics related to words is introduced. Then several important classes of words: Fibonacci, Thue-Morse and de Bruijn words. It is followed by a description basic structures for handling texts, like suffix trees, suffix arrays and de Bruijn graphs and by some elements on text compression. The chapter ends with the important issue concerning pseudocodes of algorithms. Their presentation is done in a simple and understandable form since this is a central element of the book.
Aortopulmonary window is a rare congenital heart defect. Left main coronary artery extrinsic compression by an enlarged pulmonary artery is a rare complication and a potential cause for chest pain and sudden cardiac death in patients with pulmonary hypertension. Here, we present the case of a 14-year-old boy with a large aortopulmonary window who was planned for a device closure, but during the procedure, he developed ST-T segment changes while the device was being deployed, and hence the procedure was abandoned. The boy subsequently underwent a successful surgical closure thereafter.
We study compression for function computation of sources at nodes in a network at receiver(s). The rate region of this problem has been considered under restrictive assumptions. We present results that significantly relax these assumptions. For a one-stage tree network, we characterize a rate region by a necessary and sufficient condition for any achievable coloring-based coding scheme, the coloring connectivity condition. We propose a modularized coding scheme based on graph colorings to perform arbitrarily closely to derived rate lower bounds. For a general tree network, we provide a rate lower bound based on graph entropies and show that it is tight for independent sources. We show that, in a general tree network case with independent sources, to achieve the rate lower bound, intermediate nodes should perform computations, but for a family of functions and random variables, which we call chain-rule proper sets, it suffices to have no computations at intermediate nodes to perform arbitrarily closely to the rate lower bound. We consider practicalities of coloring-based coding schemes and propose an efficient algorithm to compute a minimum-entropy coloring of a characteristic graph.
Graph Signal Processing (GSP) is a general theory, whose goal is to bring about tools for graph signals analysis that are a direct generalization of Digital Signal Processing (DSP). The goal of this chapter is understanding the graph-spectral properties of the signals, which are typically explained through the linear generative model using graph filters. Are PMU a graph signal that obeys the linear generative model prevalent in the literature? If so, what kind of graph-filter structure and excitation justifies the properties discussed already? Can we derive new strategies to sense and process these data based on GSP? By putting the link between PMU data and GSP on the right footing, we can determine to what extent GSP tools are useful, and specify how we can use the basic equations for gaining theoretical insight that support the observations.
The purpose of this chapter is to set the stage for the book and for the upcoming chapters. We first overview classical information-theoretic problems and solutions. We then discuss emerging applications of information-theoretic methods in various data-science problems and, where applicable, refer the reader to related chapters in the book. Throughout this chapter, we highlight the perspectives, tools, and methods that play important roles in classic information-theoretic paradigms and in emerging areas of data science. Table 1.1 provides a summary of the different topics covered in this chapter and highlights the different chapters that can be read as a follow-up to these topics.
In this research, atomic force microscopy (AFM) with a flat tip cantilever is utilized to measure Young's modulus of a whole yeast cell (Saccharomyces cerevisiae BY4741). The results acquired from AFM are similar to those obtained using a microfluidic chip compression system. The mechanical properties of single yeast cells are important parameters which can be examined using AFM. Conventional studies apply AFM with a sharp cantilever tip to indent the cell and measure the force-indentation curve, from which Young's modulus can be calculated. However, sharp tips introduce problems because the shape variation can lead to a different result and cannot represent the stiffness of the whole cell. It can lead to a lack of broader meaning when evaluating Young's modulus of yeast cells. In this report, we confirm the differences in results obtained when measuring the compression of a poly(dimethylsiloxane) bead using a commercial sharp tip versus a unique flat tip. The flat tip effectively avoids tip-derived errors, so we use this method to compress whole yeast cells and generate a force–deformation curve. We believe our proposed method is effective for evaluating Young's modulus of whole yeast cells.
Throughout his career as a writer, Borges strategically strove to create an image of James Joyce as the artificer of intricately woven labyrinths whose sheer scope and encyclopaedic bulk both fascinated and horrified him. The chapter charts the twists and turns of Borges’s ambivalent relationship with Joyce, from his 1925 review of Ulysses and translation of a page of its final chapter, to the development of a more problematic attitude where he sought to reposition his own art of brevity as the antithesis of Joyce’s epic legacy.
In this chapter, pectus excavatum is discussed with regard to diagnosis, surgical indications, evaluation of severity and surgical approaches.The author reviews the anesthesia implications for the minimally invasive thoracoscopic approach (currently the standard technique) as well as a multimodal approach to pain management including regional and medical management options.
Recent trends in multimedia technologies indicate the need for richer imaging modalities to increase user engagement with the content. Among other alternatives, point clouds denote a viable solution that offers an immersive content representation, as witnessed by current activities in JPEG and MPEG standardization committees. As a result of such efforts, MPEG is at the final stages of drafting an emerging standard for point cloud compression, which we consider as the state-of-the-art. In this study, the entire set of encoders that have been developed in the MPEG committee are assessed through an extensive and rigorous analysis of quality. We initially focus on the assessment of encoding configurations that have been defined by experts in MPEG for their core experiments. Then, two additional experiments are designed and carried to address some of the identified limitations of current approach. As part of the study, state-of-the-art objective quality metrics are benchmarked to assess their capability to predict visual quality of point clouds under a wide range of radically different compression artifacts. To carry the subjective evaluation experiments, a web-based renderer is developed and described. The subjective and objective quality scores along with the rendering software are made publicly available, to facilitate and promote research on the field.
The urbanised peat-rich coastal-deltaic plain of the Netherlands is severely subsiding due to human-induced phreatic groundwater level lowering, as this causes peat layers to compress and oxidise. To determine the potential susceptibility of this area to future subsidence by peat compression and oxidation, the effects of lowering present-day phreatic groundwater levels were quantitatively evaluated using a subsidence model. Input were a 3D geological subsurface voxel-model, modelled phreatic groundwater levels, and functions for peat compression and oxidation. Phreatic groundwater levels were lowered by 0.25 and 0.5m, and the resulting peat compression and oxidation over periods of 15 and 30 years were determined. The model area comprised the major cities Amsterdam and Rotterdam, and their surrounding agricultural lands.
The results revealed that for these scenarios agricultural areas may subside between 0.3 and 0.8m; potential subsidence in Amsterdam and Rotterdam is considerably lower, less than 0.4m. This is due to the presence of several metres thick anthropogenic brought-up soils overlying the peat below the urban areas, which has already compressed the peat to a depth below groundwater level, and thus minimises further compression and oxidation. In agricultural areas peat is often situated near the surface, and is therefore highly compressible and prone to oxidation. The averaged subsidence rates for the scenarios range between 7 and 13mma−1, which is corresponds to present-day rates of subsidence in the peat areas of the Netherlands. These results contrast with the trend of coastal-deltaic subsidence in other deltas, with cities subsiding faster than agricultural areas. This difference is explained by the driver of subsidence: in other deltas, subsidence of urban areas is mainly due to deep aquifer extraction, whereas in the Netherlands subsidence is due to phreatic groundwater level lowering.
The octahedral-framework mineral bernalite, Fe(OH)3, provides a rare opportunity to examine directly the effects of a vacant A site upon the physical properties of perovskite-like structures. Here, we report the effect upon compressibility. Bernalite has been reported previously as having space group Immm (Birch et al., 1993), but numerous reflections violating I-centering were observed in the present study. A case is presented for bernalite having orthorhombic space group Pmmn. Lattice parameters were refined using the Le Bail method for a metrically tetragonal cell and their variation with pressure at room temperature was determined from 17 measurements at pressures from 10–4 to 9.3 GPa using synchrotron X-ray powder diffraction. No discontinuities in the compression curves of lattice parameters were observed. Fitting to a second-order Birch-Murnaghan equation-of-state (KT0' = 4) gives V0 = 438.51±0.06 Å3 and KT0 = 78.2±0.4 GPa. Second-order fits of (a/a0)3 and (c/c0)3 give elastic moduli KT0a = 82.0(6) GPa and KT0c = 71.6(4) GPa: the shorter cation–cation distance is the more compressible. These values are very close to those of stottite, FeGe(OH)6, which has tilt system a+a+c–. The difference in the elastic moduli KT0a and KT0c of bernalite and their close similarity to the stottite values support the revised Pmmn structure (tilt system a+b+c–) for bernalite proposed here. The compressional anisotropy observed in bernalite may reflect its highly anisotropic and directional H-bonding topology.