Super-resolution: a comprehensive survey

Super-resolution, the process of obtaining one or more high-resolution images from one or more low-resolution observations, has been a very attractive research topic over the last two decades. It has found practical applications in many real-world problems in different fields, from satellite and aerial imaging to medical image processing, to facial image analysis, text image analysis, sign and number plates reading, and biometrics recognition, to name a few. This has resulted in many research papers, each developing a new super-resolution algorithm for a specific purpose. The current comprehensive survey provides an overview of most of these published works by grouping them in a broad taxonomy. For each of the groups in the taxonomy, the basic concepts of the algorithms are first explained and then the paths through which each of these groups have evolved are given in detail, by mentioning the contributions of different authors to the basic concepts of each group. Furthermore, common issues in super-resolution algorithms, such as imaging models and registration algorithms, optimization of the cost functions employed, dealing with color information, improvement factors, assessment of super-resolution algorithms, and the most commonly employed databases are discussed.     

Structure formation during spinning of poly(p-phenylenebenzobisthiazole) fiber

The structure formed in the coagulation stage of the spinning process of poly(p-phenylene benzobisthiazole) fiber is studied by electron microscopy. An oriented network of microfibrils with typical fibril diameters of about 80-100Å is observed. We suggest that these microfibrils are the fundamental structural elements of the fiber. Thus, knowledge of the mechanism by which this initial structure is formed may allow for better control of final fiber properties. The relation of structure formation during coagulation to the phase diagram of a rigid polymer solution and to the kinetic mechanism of the phase transition is discussed.     

Formation of Polymeric Lewis Acid–Lewis Base Complexes with Well-defined Organoboron Polymers

The binding of Lewis bases to organoboron polymeric Lewis acids has been studied and the parameters that determine the complexation equilibrium have been investigated, which include (i) the strength of the individual Lewis acids and Lewis bases, (ii) concentration, and (iii) temperature. While the strongly Lewis acidic borane polymers poly(4-bis(pentafluorophenyl)borylstyrene) (PS-BPf) and poly(4-(di-2-thienylboryl)styrene) (PS-BTh) form isolable complexes with strong Lewis bases such as 4-t-butylpyridine (^tPy), a temperature dependent equilibrium is established with weaker bases such as THF. Similarly, the weakly Lewis acidic boronate polymer poly(4-diethoxyborylstyrene) (PS-BOEt) undergoes a temperature dependent equilibrium with the strong Lewis base 4-dimethylaminopyridine (DMAP), while poly(4-pinacolatoborylstyrene) (PS-BPin) does not significantly bind to pyridine bases. Decomplexation of PS-BTh· ^t Py is achieved by treatment with the stronger Lewis acid, B(C₆F₅)₃, thereby confirming the reversible nature of the polymeric Lewis acid–base adducts. This paper is dedicated to Professor Ian Manners in gratitude of his guidance throughout the years and recognition of his scientific accomplishments     

Online scheduling and placement of hardware tasks with multiple variants on dynamically reconfigurable field-programmable gate arrays

Hardware task scheduling and placement at runtime plays a crucial role in achieving better system performance by exploring dynamically reconfigurable Field-Programmable Gate Arrays (FPGAs). Although a number of online algorithms have been proposed in the literature, no strategy has been engaged in efficient usage of reconfigurable resources by orchestrating multiple hardware versions of tasks. By exploring this flexibility, on one hand, the algorithms can be potentially stronger in performance; however, on the other hand, they can suffer much more runtime overhead in selecting dynamically the best suitable variant on-the-fly based on its runtime conditions imposed by its runtime constraints. In this work, we propose a fast efficient online task scheduling and placement algorithm by incorporating multiple selectable hardware implementations for each hardware request; the selections reflect trade-offs between the required reconfigurable resources and the task runtime performance. Experimental studies conclusively reveal the superiority of the proposed algorithm in terms of not only scheduling and placement quality but also faster runtime decisions over rigid approaches.     

Tailoring of Surfaces with Ultrathin Layers for Controlled Binding of Biopolymers and Adhesion and Guidance of Cells

Various strategies are described for the bio-functionalization of solid substrates by design of interfacial architectures. The first approach is based on the self-assembly process of long-chain thiol molecules from solution to a (noble) metal surface. If some of these building blocks carry a binding site (ligand) for proteins (receptors, antibodies, etc.) the metal surface can be tailored for maximum specific binding while simultaneously minimizing nonspecific adsorption. The second concept is based on polymers that are covalently attached to (oxide) surfaces. The preparation of these (end-) grafted functional polymers involves either the binding of preformed macromolecules to corresponding sites at the surface of the support or the recently introduced “grafting-from” method, by which an initiator molecule is first covalently bound to the surface and then activated — either by heat or light — in the presence of suitable monomer units such that a polymer chain grows from the solid/solution interface. Finally, the functionalization of patterned surfaces by peptide chains that mimic the binding domains of cell adhesion proteins is summarized. It is demonstrated that not only the selective adhesion of neuronal cells can then be controlled, but also their development with the outgrowth of dendrites and axons.     

Synthesis of transparent fluorocarbon elastomers: Effect of crosslinker type and electron beam irradiation level on physical and mechanical behavior

Saturated fluorocarbon elastomers are very resistant to chemical reactions, including those of a crosslinking nature. In order to study proper methods of preparing these materials, Viton GLT was mixed with various levels of trimethylol propane trimethacrylate, TMPTM, and triallyl isocyanurate, Diak #7. After molding, the materials were subjected to electron beam irradiation. The glass transition, rubbery modulus, viscoelastic behavior, and equilibrium swelling were used to characterize the materials as a function of crosslinker and irradiation level. In general, the modulus and gel fraction increased with both crosslinker content and irradiation level. Mixtures of both crosslinking monomers produced an unexpected synergism, yielding higher tensile strength, and earlier onset of gelation.     

A new method for measuring the transfer of oxygen in liquids. MeasurementS of oxygen transfer from bubbles in water and in water + 1-butanol

At the base of a column of liquid 20 cm in diameter and well over 1 m in height, oxygen bubbles of constant volume were formed and released with a frequency of approximately one bubble per second. Measurements were carried out on bubbles with volumes ranging from 0·2 to 2 cm³. The mass transfer per bubble was determined by measuring the increase in oxygen concentration of the liquid phase with an oxygen electrode and counting the number of bubbles. The results were reproducible within 3 per cent, and it is probable that still better results are attainable with this method.The measurements were initially performed in distilled water to test the apparatus. Later, water—butanol mixtures were employed in order to determine the influence of butanol on the mass transfer. The results of the latter experiments have been checked with a theory published previously [23, 24]. Theory and results appear to be in satisfactory agreement.     

Bark beetle olfaction. III. Antennal olfactory responsiveness ofDendroctonus frontalis Zimmerman andD. brevicomis Le Conte (Coleoptera: Scolytidae) to aggregation pheromones and host tree terpene hydrocarbons

Electroantennograms from males and females ofDendroctonus frontalis andD. brevicomis in response to serial dilutions of the pheromonesexo brevicomin and frontalin and the host terpene hydrocarbons 3-carene and α-pinene show no significant differences in the threshold concentration for response to the compounds for either sex or species. The intensity of response was greater to higher concentrations of the pheromones (10 to >10⁴ μg) than the terpene hydrocarbons, suggesting the presence of more receptors on the antennae for pheromones than terpene hydrocarbons. Antennal olfactory responses to the compounds did not correlate to published data on behavioral responses by the beetles to the compounds in both field and laboratory studies. Adaptation experiments indicated that forD. frontalis, both frontalin andexo brevicomin share the same receptors on the antennae. The results indicated that the terpene hydrocarbons share some, but not all, of the same receptors.     

Effect of lecithin on jejunal absorption of micellar lipids in man and on their monomer activity in vitro

The effect of lecithin on jejunal absorption of fatty acids and octadecenoylglycerol was studied in healthy volunteers with a jejunal perfusion system which excluded pancreatic and biliary secretions from the test segment. Lecithin significantly reduced the absorption of oleic acid (P<0.05) and octadecenoylglycerol (P<0.01), while it had no effect on the absorption of ricinoleic acid. In vitro, lecithin reduced monomer activities of all three lipids; the changes were greater for oleic acid and octadecenoylglycerol than for ricinoleic acid (P<0.02). From these data it is concluded that lecithin reduces monomer activity of fatty acids in mixed micellar solutions and that it can thereby reduce the absorption rates of micellar lipids. Intact lecithin is not absorbed under these conditions. Maldigestion of lecithin in pancreatic insufficiency may, therefore, aggravate the steatorrhea observed in this condition.