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Cellulose, being a renewable and abundant biopolymer, has garnered significant attention for its unique properties and potential applications in hybrid materials. Understanding the hierarchical arrangement of cellulose nanofibers is crucial for developing cellulose-based materials with enhanced mechanical properties. In this study, the use of Scanning Electron Diffraction (SED) is presented to map the nanoscale orientation of cellulose fibers in a bio-composite material with a preserved wood cell structure. The SED data provides detailed insights into the ordering of cellulose with an extraordinary resolution of approximate to 15 nm. It enables a quantitative analysis of the fiber orientation over regions as large as entire cells. A highly organized arrangement of cellulose fibers within the secondary cell wall is observed, with a gradient of orientations toward the outer part of the wall. The in-plane fiber rotation is quantified, revealing a uniform orientation close to the middle lamella. Transversely sectioned material exhibits similar trends, suggesting a layered cell wall structure. Based on the SED data, a 3D model depicting the complex helical alignment of fibers throughout the cell wall is constructed. This study demonstrates the unique opportunities SED provides for characterizing the nanoscale hierarchical arrangement of cellulose nanofibers, empowering further research on a range of hybrid materials. Fundamental knowledge about the hierarchical arrangement of cellulose nanofiber is of great importance in developing new cellulose-based hybrid materials. Scanning electron diffraction is employed to map the cellulose nanofiber orientations throughout a wood-derived bio-based material. SED data reveals insights into cellulose alignment and enables precise quantitative fiber orientation analysis with a nanoscale spatial resolution.image

Cellulose, being a renewable and abundant biopolymer, has garnered significant attention for its unique properties and potential applications in hybrid materials. Understanding the hierarchical arrangement of cellulose nanofibers is crucial for developing cellulose-based materials with enhanced mechanical properties. In this study, the use of Scanning Electron Diffraction (SED) is presented to map the nanoscale orientation of cellulose fibers in a bio-composite material with a preserved wood cell structure. The SED data provides detailed insights into the ordering of cellulose with an extraordinary resolution of ≈15 nm. It enables a quantitative analysis of the fiber orientation over regions as large as entire cells. A highly organized arrangement of cellulose fibers within the secondary cell wall is observed, with a gradient of orientations toward the outer part of the wall. The in-plane fiber rotation is quantified, revealing a uniform orientation close to the middle lamella. Transversely sectioned material exhibits similar trends, suggesting a layered cell wall structure. Based on the SED data, a 3D model depicting the complex helical alignment of fibers throughout the cell wall is constructed. This study demonstrates the unique opportunities SED provides for characterizing the nanoscale hierarchical arrangement of cellulose nanofibers, empowering further research on a range of hybrid materials., QC 20240624

Cooperative games model situations in which a group of players work together to make a profit. Frequently, in cooperative situations there are dependency or hierarchical relationships between the players, which must be taken into account when allocating the common profit obtained by the grand coalition. Multiple structures have been used in the literature to model those relationships, and several values have been proposed, but there is something in common in all of them: if a player can veto the participation of another in any coalition, then both players will receive the same share of the profit derived from the active cooperation of the vetoed player. In other words, actively cooperating and giving permission to cooperate are equally valued. In many situations this is neither fair nor realistic. In this paper we introduce a family of allocation rules for cooperative games with authorization structure, which reward positional power less than active cooperation.

The hierarchical structures of poly(styrene-ran-butadiene) (SBR) rubber/carbon black (CB) systems vulcanized with sulfur and ZnO have been clarified using anomalous small-angle X-ray scattering (ASAXS) near the Zn absorption edge. In the case of SBR/CB systems vulcanized with peroxide, it has been found previously that the hierarchical structures formed by CB consist of aggregates of primary particles and agglomerates of those aggregates with mass-fractal dimensions. However, to date the hierarchical structures in SBR/CB systems vulcanized with sulfur and ZnO have not been well investigated, despite being commonly used. This is because the strong scattering contrast of Zn prevents the quantitative analyses of the hierarchical structures of CB using X-ray scattering. In this study, the effects of Zn on the scattering intensity were eliminated and the structure factors of CB in SBR/CB systems were obtained using the ASAXS method. By extrapolating to the zero volume fraction of CB, the particle structure factor of the CB aggregates was estimated and it was found that the CB aggregates consist of closely packed CB primary particles. The presence of large particles of ZnO and particles of ZnS on the order of 10 nm in size is confirmed.

A Zn anode can offset the low energy density of a flow battery for a balanced approach toward electricity storage. Yet, when targeting inexpensive, long-duration storage, the battery demands a thick Zn deposit in a porous framework, whose heterogeneity triggers frequent dendrite formation and jeopardizes the stability of the battery. Here, Cu foam is transferred into a hierarchical nanoporous electrode to homogenize the deposition. It begins with alloying the foam with Zn to form Cu5Zn8, whose depth is controlled to retain the large pores for a hydraulic permeability ≈10−11 m2. Dealloying follows to create nanoscale pores and abundant fine pits below 10 nm, where Zn can nucleate preferentially due to the Gibbs–Thomson effect, as supported by a density functional theory simulation. Morphological evolution monitored by in situ microscopy confirms uniform Zn deposition. The electrode delivers 200 h of stable cycles in a Zn–I2 flow battery at 60 mAh cm−2 and 60 mA cm−2, performance that meets practical demands. © 2023 Wiley-VCH GmbH.

©2022 IOP Publishing Ltd I warmly thank M. Victoria Hernández for a critical reading of the manuscript., Biological systems display a broad palette of hierarchically ordered designs spanning over many orders of magnitude in size. Remarkably enough, periodic order, which profusely shows up in non-living ordered compounds, plays a quite subsidiary role in most biological structures, which can be appropriately described in terms of the more general aperiodic crystal notion instead. In this topical review I shall illustrate this issue by considering several representative examples, including botanical phyllotaxis, the geometry of cell patterns in tissues, the morphology of sea urchins, or the symmetry principles underlying virus architectures. In doing so, we will realize that albeit the currently adopted quasicrystal notion is not general enough to properly account for the rich structural features one usually finds in biological arrangements of matter, several mathematical tools and fundamental notions belonging to the aperiodic crystals science toolkit can provide a useful modeling framework to this end., Depto. de Física de Materiales, Fac. de Ciencias Físicas, TRUE, pub

Solar-powered water evaporation is a straightforward, practical approach to use solar energy for water desalination. Solar absorbers made from photothermal materials capable of effectively confining heat and pumping water to the evaporation surface are essential for a high energy efficiency. However, separate designs of water transport routes and thermal insulating layers are required to simultaneously achieve desired water and thermal managements. This work reports an integrated design for efficient multifunctional capabilities through rational assembly of spectrally modified Ti3C2Tx (SM-Ti3C2Tx) nanosheets and polyvinyl alcohol (PVA) into a multiscale 3D aerogel with a feather-like microstructure. The aerogel contains longitudinal struts with transversely parallel ligaments developed at an angle of ≈60° from the struts, resembling the microstructure of down feathers in penguins and thus leading to excellent thermal insulation. The hydrophilic porous ligaments serve as upward water transport channels, pumping the water to the evaporation surface while confining it within the ligaments to avoid oversaturation. These functional features endow the composite aerogel with a high energy efficiency of 88.52% and an evaporation rate of 0.92 kg m−2 h−1 at a weak solar irradiance of 0.5-sun, indicating its great potential for practical solar-powered water desalination under natural sunlight. © 2022 Wiley-VCH GmbH

Owing to the low theoretical potential of the urea oxidation reaction (UOR), urea electrolysis is an energy-saving technique for the generation of hydrogen. Herein, a hierarchical structure of CuO nanowires decorated with nickel hydroxide supported on 3D Cu foam is constructed. Combined theoretical and experimental analyses demonstrate the high reactivity and selectivity of CuO and Ni(OH)2 toward the UOR instead of the oxygen evolution reaction. The hierarchical structure creates a synergistic effect between the two highly active sites, enabling an exceptional UOR activity with a record low potential of 1.334 V (vs the reversible hydrogen electrode) to reach 100 mA cm−2 and a low Tafel slope of 14 mV dec−1 in 1 m KOH and 0.5 m urea electrolyte. Assembling full urea electrolysis driven by this developed UOR electrocatalyst as the anode and a commercial Pt/C electrocatalyst as the cathode provides a current density of 20 mA cm−2 at a cell voltage of ≈1.36 V with promising operational stability for at least 150 h. This work not only enriches the UOR material family but also significantly advances energy-saving hydrogen production.

The concept of “complexity” is considered in relation to radiation processes in condensed matter. It is shown that a combination of such properties as nanoscale, fractality, low dimension, chirality, and hierarchy in combination with high nonequilibrium create conditions for the manifestation of unusual “emergent” radiation effects (radiation synergetics, great dose reduction of threshold radiation effects, etc.). Examples of radiation effects in living and inanimate systems, interpreted within the framework of the concept of “complexity”, are presented. An overview of both previously obtained and new results is presented. © 2022, Pleiades Publishing, Ltd.

Effects of Micro and Nano Surface Roughness onCavitation Damage of Metallic SurfacesbyJuan Carlos Gonzalez-ParraDoctor of Philosophy, Graduate Program in Mechanical EngineeringUniversity of California, Riverside, September 2022 Dr. Guillermo Aguilar and Dr. Natanael Cuando-Espitia, Co-ChairpersonsSurface parameters modification via laser irradiation has been a technique used to process materials since de discovery of the laser itself. One of these techniques is nano texturization of a surface by the means of focusing laser irradiation onto it and creating Laser-Induced Periodic Surface Structures (LIPSS). Despite the fact LIPSS have been around since the early dates of laser processing, their physical mechanism is still discussed. These LIPSS’ formation theories have been proposed since the 1980s with the Surface Plasmon Polariton model and Sipe’s theory, and, more recently, the Sipe-Drude model. In recent years, the research has been shifting to their applications. On this work, we suggest a modification of the surface via laser processing for reducing cavitation erosion damage. This proposal is divided in 2 main sections. First, a surface was nanotextured by scribing LIPSS on it. As it is described in the following sections, this processing avoids remnant microbubbles generated after the collapse of a cavitation bubble to attach to the surface, impeding those microbubbles to be activated near the surface and act as a nucleation point when another cavitation bubble is formed. Secondly, by adding a microstructure, a hierarchical structure was generated. This hierarchical structure allowed not only minimizing attached remnant microbubbles, but also the modification of the cavitation bubble’s rebound dynamics. By exclusively generating LIPSS on the surface of the material, we achieved a reduction of erosion by a factor of 3 when compared to an untreated surface. On the other hand, by evaluating it on a hierarchical structure we obtained an improvement of up to a facto

Boiling is an effective energy-transfer process with substantial utility in energy applications. Boiling performance is described mainly by the heat-transfer coefficient (HTC) and critical heat flux (CHF). Recent efforts for the simultaneous enhancement of HTC and CHF have been limited by an intrinsic trade-off between them-HTC enhancement requires high nucleation-site density, which can increase bubble coalescence resulting in limited CHF enhancement. In this work, this trade-off is overcome by designing three-tier hierarchical structures. The bubble coalescence is minimized to enhance the CHF by defining nucleation sites with microcavities interspersed within hemi-wicking structures. Meanwhile, the reduced nucleation-site density is compensated for by incorporating nanostructures that promote evaporation for HTC enhancement. The hierarchical structures demonstrate the simultaneous enhancement of HTC and CHF up to 389% and 138%, respectively, compared to a smooth surface. This extreme boiling performance can lead to significant energy savings in a variety of boiling applications.

Peptide derivatives and, most specifically, their self-assembled supramolecular structures are being considered in the design of novel biofunctional materials. Although the self-assembly of triphenylalanine homopeptides has been found to be more versatile than that of homopeptides containing an even number of residues (i.e. diphenylalanine and tetraphenylalanine), only uncapped triphenylalanine (FFF) and a highly aromatic analog blocked at both the N- and C-termini with fluorenyl-containing groups (Fmoc-FFF-OFm), have been deeply studied before. In this work, we have examined the self-assembly of a triphenylalanine derivative bearing 9-fluorenylmethyloxycarbonyl and benzyl ester end-capping groups at the N- and C-termini, respectively (Fmoc-FFF-OBzl). The antiparallel arrangement clearly dominates in ß-sheets formed by Fmoc-FFF-OBzl, whereas the parallel and antiparallel dispositions are almost isoenergetic in Fmoc-FFF-OFm ß-sheets and the parallel one is slightly favored for FFF. The effects of both the peptide concentration and the medium on the self-assembly process have been examined considering Fmoc-FFF-OBzl solutions in a wide variety of solvent:co-solvent mixtures. In addition, Fmoc-FFF-OBzl supramolecular structures have been compared to those obtained for FFF and Fmoc-FFF-OFm under identical experimental conditions. The strength of p-p stacking interactions involving the end-capping groups plays a crucial role in the nucleation and growth of supramolecular structures, which determines the resulting morphology. Finally, the influence of a non-invasive external stimulus, ultrasounds, on the nucleation and growth of supramolecular structures has been examined. Overall, FFF-based peptides provide a wide range of supramolecular structures that can be of interest in the biotechnological field., Postprint (author's final draft)

This chapter outlines a quantitative method for analyzing location descriptions. Generally, such a quantitative analysis allows for identifying predominant features of these descriptions and, given a sufficiently large corpus, may allow for statistical inferences. Here, an English translation of Biondo’s chapter on the region Latium is used as a small case study illustrating the method. The analyzed features include the frequency (distribution) of the level of granularity of those entities referred to in the descriptions, which spatial hierarchical structures emerge from referring to different entities on potentially different levels of granularity and the frequency of these structures, and which spatial relationships between entities dominate in the descriptions. The chapter presents results of this analysis and discusses them in detail, also pointing out limitations of the method. However, mainly the chapter is to be read as an introduction to this particular analysis approach, which may be used to complement other analyses and may offer insights not otherwise gained.

This chapter outlines a quantitative method for analyzing location descriptions. Generally, such a quantitative analysis allows for identifying predominant features of these descriptions and, given a sufficiently large corpus, may allow for statistical inferences. Here, an English translation of Biondo’s chapter on the region Latium is used as a small case study illustrating the method. The analyzed features include the frequency (distribution) of the level of granularity of those entities referred to in the descriptions, which spatial hierarchical structures emerge from referring to different entities on potentially different levels of granularity and the frequency of these structures, and which spatial relationships between entities dominate in the descriptions. The chapter presents results of this analysis and discusses them in detail, also pointing out limitations of the method. However, mainly the chapter is to be read as an introduction to this particular analysis approach, which may be used to complement other analyses and may offer insights not otherwise gained.

This chapter outlines a quantitative method for analyzing location descriptions. Generally, such a quantitative analysis allows for identifying predominant features of these descriptions and, given a sufficiently large corpus, may allow for statistical inferences. Here, an English translation of Biondo’s chapter on the region Latium is used as a small case study illustrating the method. The analyzed features include the frequency (distribution) of the level of granularity of those entities referred to in the descriptions, which spatial hierarchical structures emerge from referring to different entities on potentially different levels of granularity and the frequency of these structures, and which spatial relationships between entities dominate in the descriptions. The chapter presents results of this analysis and discusses them in detail, also pointing out limitations of the method. However, mainly the chapter is to be read as an introduction to this particular analysis approach, which may be used to complement other analyses and may offer insights not otherwise gained.

Aqueous Zn-ion batteries have long been considered as a promising substitute for Li-ion batteries due to their low cost, improved safety, and better environmental sustainability. However, the unsatisfactory energy/power density and inferior cycling ability are the two key obstacles of the aqueous nickel-zinc (Ni-Zn) battery, mainly due to the low capacity and serious irreversibility of its Ni-based cathode. To solve these issues, femtosecond laser texturing along with chemical bath deposition was performed to synthesize a 3D hierarchical NiO@Ni(OH)2 composite structure on a nickel foil as an ultrahigh performance cathode for the Ni-Zn battery. Compared with the nickel foil treated only by chemical bath deposition (denoted as NN@NF), the areal capacity of the Ni foil treated by femtosecond laser texturing and the chemical deposition technique (denoted as NN@LTNF) was substantially improved, achieving 0.593 mA h cm-2 at 10 mA cm-2. Moreover, the as-prepared NN@LTNF//Zn battery demonstrated an ideal peak energy density (0.586 mW h cm-2) and power density (86.7 mW cm-2). Particularly, the NN@LTNF//Zn battery could deliver outstanding reversibility and excellent cycling durability (90.2% capacity retention after 1800 cycles). The prominent improvement of electrochemical performance can be attributed to the NiO@Ni(OH)2 composite structure with 3D network morphology and superhydrophilic property, which can facilitate electrolyte penetration and thus ion mobility to active reaction sites. This research may provide promising vistas for laser-processed advanced Ni-based cathodes in ultrahigh electrochemical performance aqueous Ni-Zn batteries. ©

Owing to the low theoretical potential of the urea oxidation reaction (UOR), urea electrolysis is an energy-saving technique for the generation of hydrogen. Herein, a hierarchical structure of CuO nanowires decorated with nickel hydroxide supported on 3D Cu foam is constructed. Combined theoretical and experimental analyses demonstrate the high reactivity and selectivity of CuO and Ni(OH)2 toward the UOR instead of the oxygen evolution reaction. The hierarchical structure creates a synergistic effect between the two highly active sites, enabling an exceptional UOR activity with a record low potential of 1.334 V (vs the reversible hydrogen electrode) to reach 100 mA cm−2 and a low Tafel slope of 14 mV dec−1 in 1 m KOH and 0.5 m urea electrolyte. Assembling full urea electrolysis driven by this developed UOR electrocatalyst as the anode and a commercial Pt/C electrocatalyst as the cathode provides a current density of 20 mA cm−2 at a cell voltage of ≈1.36 V with promising operational stability for at least 150 h. This work not only enriches the UOR material family but also significantly advances energy-saving hydrogen production.

Solar-powered water evaporation is a straightforward, practical approach to use solar energy for water desalination. Solar absorbers made from photothermal materials capable of effectively confining heat and pumping water to the evaporation surface are essential for a high energy efficiency. However, separate designs of water transport routes and thermal insulating layers are required to simultaneously achieve desired water and thermal managements. This work reports an integrated design for efficient multifunctional capabilities through rational assembly of spectrally modified Ti3C2Tx (SM-Ti3C2Tx) nanosheets and polyvinyl alcohol (PVA) into a multiscale 3D aerogel with a feather-like microstructure. The aerogel contains longitudinal struts with transversely parallel ligaments developed at an angle of ≈60° from the struts, resembling the microstructure of down feathers in penguins and thus leading to excellent thermal insulation. The hydrophilic porous ligaments serve as upward water transport channels, pumping the water to the evaporation surface while confining it within the ligaments to avoid oversaturation. These functional features endow the composite aerogel with a high energy efficiency of 88.52% and an evaporation rate of 0.92 kg m−2 h−1 at a weak solar irradiance of 0.5-sun, indicating its great potential for practical solar-powered water desalination under natural sunlight. © 2022 Wiley-VCH GmbH

Various performance benefits such as low latency and high bandwidth have turned fog computing into a well-accepted extension of the cloud computing paradigm. Many fog computing systems have been proposed so far, consisting of distributed compute nodes which are often organized hierarchically in layers. To achieve low latency, these systems commonly rely on the assumption that the nodes of adjacent layers reside close to each other. However, this assumption may not hold in fog computing systems that span over large geographical areas, due to the wide distribution of the nodes. To avoid relying on this assumption, in this paper we design distributed algorithms whereby the compute nodes measure the network proximity to each other, and self-organize into a hierarchical or a flat structure accordingly. Moreover, we implement these algorithms on geographically distributed compute nodes, and we experiment with image processing and smart city use cases. Our results show that compared to alternative methods, the proposed algorithms decrease the communication latency of latency-sensitive processes by 27%–43%, and increase the available network bandwidth by 36%–86%. Furthermore, we analyze the scalability of our algorithms, and we show that a flat structure (i.e., without layers) scales better than the commonly used layered hierarchy due to generating less overhead when the size of the system grows.

Two frontier crystalline porous framework materials, namely, metal-organic frameworks (MOFs) and covalent organic frameworks (COFs), have been widely explored owing to their outstanding physicochemical properties. While each type of framework has its own intrinsic advantages and shortcomings for specific applications, combining the complementary properties of the two materials allows the engineering of new classes of hybrid porous crystalline materials with properties superior to the individual components. Since the first report of MOF/COF hybrid in 2016, it has rapidly evolved as a novel platform for diverse applications. The state-of-art advances in the various synthetic approaches of MOF/COF hybrids are hereby summarized, together with their applications in different areas. Perspectives on the main challenges and future opportunities are also offered in order to inspire a multidisciplinary effort toward the further development of chemically diverse, multi-functional hybrid porous crystalline materials.

Two frontier crystalline porous framework materials, namely, metal-organic frameworks (MOFs) and covalent organic frameworks (COFs), have been widely explored owing to their outstanding physicochemical properties. While each type of framework has its own intrinsic advantages and shortcomings for specific applications, combining the complementary properties of the two materials allows the engineering of new classes of hybrid porous crystalline materials with properties superior to the individual components. Since the first report of MOF/COF hybrid in 2016, it has rapidly evolved as a novel platform for diverse applications. The state-of-art advances in the various synthetic approaches of MOF/COF hybrids are hereby summarized, together with their applications in different areas. Perspectives on the main challenges and future opportunities are also offered in order to inspire a multidisciplinary effort toward the further development of chemically diverse, multi-functional hybrid porous crystalline materials.

Owing to the low theoretical potential of the urea oxidation reaction (UOR), urea electrolysis is an energy-saving technique for the generation of hydrogen. Herein, a hierarchical structure of CuO nanowires decorated with nickel hydroxide supported on 3D Cu foam is constructed. Combined theoretical and experimental analyses demonstrate the high reactivity and selectivity of CuO and Ni(OH)2 toward the UOR instead of the oxygen evolution reaction. The hierarchical structure creates a synergistic effect between the two highly active sites, enabling an exceptional UOR activity with a record low potential of 1.334 V (vs the reversible hydrogen electrode) to reach 100 mA cm−2 and a low Tafel slope of 14 mV dec−1 in 1 m KOH and 0.5 m urea electrolyte. Assembling full urea electrolysis driven by this developed UOR electrocatalyst as the anode and a commercial Pt/C electrocatalyst as the cathode provides a current density of 20 mA cm−2 at a cell voltage of ≈1.36 V with promising operational stability for at least 150 h. This work not only enriches the UOR material family but also significantly advances energy-saving hydrogen production. © 2021 Wiley-VCH GmbH

This article focuses on the study of hierarchical lexical-semantic (terminological) fields dental discourse in terms of comparative paradigms based on the Russian and English languages. Modern medical terminology is characterized as a system of medical and paramedical terms resulting from centuries-old development of world healing. Cognitive communication the space of dentistry accumulates a universal general language, general medical information, based on the prevailing medical terminology fund, the core of medical terminology, and narrowly professional information, forming a wide peripheral a structure representing specific professional knowledge, due to a change in the scientific picture of the world.

The article discusses the essence of the integrated didactic system in preschooleducation, aspects of realization, those of relying on the integration ofactivities. In particular, the importance of integrating meaningful and activeaspects into the educational process is speculated upon.

This article focuses on the study of hierarchical lexical-semantic (terminological) fields dental discourse in terms of comparative paradigms based on the Russian and English languages. Modern medical terminology is characterized as a system of medical and paramedical terms resulting from centuries-old development of world healing. Cognitive communication the space of dentistry accumulates a universal general language, general medical information, based on the prevailing medical terminology fund, the core of medical terminology, and narrowly professional information, forming a wide peripheral a structure representing specific professional knowledge, due to a change in the scientific picture of the world.

The article discusses the essence of the integrated didactic system in preschooleducation, aspects of realization, those of relying on the integration ofactivities. In particular, the importance of integrating meaningful and activeaspects into the educational process is speculated upon.

The article discusses the essence of the integrated didactic system in preschooleducation, aspects of realization, those of relying on the integration ofactivities. In particular, the importance of integrating meaningful and activeaspects into the educational process is speculated upon.

The article discusses the essence of the integrated didactic system in preschooleducation, aspects of realization, those of relying on the integration ofactivities. In particular, the importance of integrating meaningful and activeaspects into the educational process is speculated upon.

The article discusses the essence of the integrated didactic system in preschooleducation, aspects of realization, those of relying on the integration ofactivities. In particular, the importance of integrating meaningful and activeaspects into the educational process is speculated upon.

This article focuses on the study of hierarchical lexical-semantic (terminological) fields dental discourse in terms of comparative paradigms based on the Russian and English languages. Modern medical terminology is characterized as a system of medical and paramedical terms resulting from centuries-old development of world healing. Cognitive communication the space of dentistry accumulates a universal general language, general medical information, based on the prevailing medical terminology fund, the core of medical terminology, and narrowly professional information, forming a wide peripheral a structure representing specific professional knowledge, due to a change in the scientific picture of the world.

This article focuses on the study of hierarchical lexical-semantic (terminological) fields dental discourse in terms of comparative paradigms based on the Russian and English languages. Modern medical terminology is characterized as a system of medical and paramedical terms resulting from centuries-old development of world healing. Cognitive communication the space of dentistry accumulates a universal general language, general medical information, based on the prevailing medical terminology fund, the core of medical terminology, and narrowly professional information, forming a wide peripheral a structure representing specific professional knowledge, due to a change in the scientific picture of the world.

The article discusses the essence of the integrated didactic system in preschooleducation, aspects of realization, those of relying on the integration ofactivities. In particular, the importance of integrating meaningful and activeaspects into the educational process is speculated upon.

This article focuses on the study of hierarchical lexical-semantic (terminological) fields dental discourse in terms of comparative paradigms based on the Russian and English languages. Modern medical terminology is characterized as a system of medical and paramedical terms resulting from centuries-old development of world healing. Cognitive communication the space of dentistry accumulates a universal general language, general medical information, based on the prevailing medical terminology fund, the core of medical terminology, and narrowly professional information, forming a wide peripheral a structure representing specific professional knowledge, due to a change in the scientific picture of the world.

This article focuses on the study of hierarchical lexical-semantic (terminological) fields dental discourse in terms of comparative paradigms based on the Russian and English languages. Modern medical terminology is characterized as a system of medical and paramedical terms resulting from centuries-old development of world healing. Cognitive communication the space of dentistry accumulates a universal general language, general medical information, based on the prevailing medical terminology fund, the core of medical terminology, and narrowly professional information, forming a wide peripheral a structure representing specific professional knowledge, due to a change in the scientific picture of the world.

This article focuses on the study of hierarchical lexical-semantic (terminological) fields dental discourse in terms of comparative paradigms based on the Russian and English languages. Modern medical terminology is characterized as a system of medical and paramedical terms resulting from centuries-old development of world healing. Cognitive communication the space of dentistry accumulates a universal general language, general medical information, based on the prevailing medical terminology fund, the core of medical terminology, and narrowly professional information, forming a wide peripheral a structure representing specific professional knowledge, due to a change in the scientific picture of the world.

To achieve the optimized performance and the widespread application of thermoelectric materials, it is crucial to decouple the highly interrelated thermoelectric parameters of materials. In this study, we illustrate that phonon and carrier transport properties of n-type Bi2Te3-based composites can be simultaneously optimized through alloying Cu2Se. Owing to the chemical reactions between the Bi2Te3 matrix and the Cu2Se additives during the sample preparation, the carrier concentration and density-of-states effective mass can be tuned to optimize the carrier transport properties, while the lattice thermal conductivity can be reduced by introducing hierarchical structures including point defects, Cu7Te5 inclusions, phase boundaries and localized Te-deficient regions. As a result, an enhanced thermoelectric performance is achieved compared with pristine Bi2Te3. Our study indicates the alloying Cu2Se can synergistically control the thermoelectric properties of Bi2Te3.

Liquid metal dealloying (LMD) has recently attracted significant attention. Because the LMD process enables the production of three-dimensional (3D) interconnected non-noble metallic materials. In addition, the metallic melt medium is useful for the development of heterostructure (HS) metal–metal composites. However, the solidified liquid metal phase (low melting point metals such as Mg, Bi, Sn, or Cu) has a much lower strength than the developed ligament phase (e.g., Fe, FeCr, Ti, etc.). In this study, the soft Mg phase was strengthened by adding alloying element of Ni. A eutectic composition of Mg–10 at.% Ni melt leads to the formation of fine eutectic structure of (Mg–Mg2Ni) within 3D interconnected morphology. This hierarchical heterostructured composite consisted of FeCr ligament and Mg–Mg2Ni lamellar, and a high yield strength of 280 MPa and a noticeable elongation (1.5%) were achieved. The complex 3D morphology of ligament and lamellar geometrically constraint each other, and it prevents the early fracture of brittle Mg–Mg2Ni lamellar phase. The alloy design for the LMD melt gives insights for hierarchical HS materials with outstanding mechanical properties for structural applications. © 2021 The Authors.

Pt based materials are the most efficient electrocatalysts for the oxygen reduction reaction (ORR) and methanol oxidation reaction (MOR) in fuel cells. Maximizing the utilization of Pt based materials by modulating their morphologies to expose more active sites is a fundamental objective for the practical application of fuel cells. Herein, we report a new class of hierarchically skeletal Pt-Ni nanocrystals (HSNs) with a multi-layered structure, prepared by an inorganic acid-induced solvothermal method. The addition of H2SO4 to the synthetic protocol provides a critical trigger for the successful growth of Pt-Ni nanocrystals with the desired structure. The Pt-Ni HSNs synthesized by this method exhibit enhanced mass activity of 1.25 A mgpt−1 at 0.9 V (versus the reversible hydrogen electrode) towards ORR in 0.1-M HClO4, which is superior to that of Pt-Ni multi-branched nanocrystals obtained by the same method in the absence of inorganic acid; it is additionally 8.9-fold higher than that of the commercial Pt/C catalyst. Meanwhile, it displays enhanced stability, with only 21.6% mass activity loss after 10,000 cycles (0.6–1.0 V) for ORR. Furthermore, the Pt-Ni HSNs show enhanced activity and anti-toxic ability in CO for MOR. The superb activity of the Pt-Ni HSNs for ORR and MOR is fully attributed to an extensively exposed electrochemical surface area and high intrinsic activity, induced by strain effects, provided by the unique hierarchically skeletal alloy structure. The novel open and hierarchical structure of Pt-Ni alloy provides a promising approach for significant improvements of the activity of Pt based alloy electrocatalysts. © 2021 Dalian Institute of Chemical Physics, the Chinese Academy of Sciences.

The problem of computational design for menu systems has been addressed in some specific cases such as the linear menu (list). The classical approach has been to model this problem as an assignment task, where commands are assigned to menu positions while optimizing for users’ selection performance and grouping of associated items. However, we show that this approach fails with larger, hierarchically organized menus because it does not take into account the ways in which users navigate hierarchical structures. This paper addresses the computational menu design problem by presenting a novel integer programming formulation that yields usable, well-ordered command hierarchies from a single model. First, it introduces a novel objective function based on information foraging theory, which minimizes navigation time in a hierarchical structure. Second, it models the hierarchical menu design problem as a combination of the exact set covering problem and the assignment problem, organizing commands into ordered groups of ordered groups. The approach is efficient for large, representative instances of the problem. In a controlled usability evaluation, the performance of computationally designed menus was ∼25% faster to use than existing commercial designs. We discuss applications of this approach for personalization and adaptation. © 2021

Two frontier crystalline porous framework materials, namely, metal-organic frameworks (MOFs) and covalent organic frameworks (COFs), have been widely explored owing to their outstanding physicochemical properties. While each type of framework has its own intrinsic advantages and shortcomings for specific applications, combining the complementary properties of the two materials allows the engineering of new classes of hybrid porous crystalline materials with properties superior to the individual components. Since the first report of MOF/COF hybrid in 2016, it has rapidly evolved as a novel platform for diverse applications. The state-of-art advances in the various synthetic approaches of MOF/COF hybrids are hereby summarized, together with their applications in different areas. Perspectives on the main challenges and future opportunities are also offered in order to inspire a multidisciplinary effort toward the further development of chemically diverse, multi-functional hybrid porous crystalline materials.

The article discusses the essence of the integrated didactic system in preschooleducation, aspects of realization, those of relying on the integration ofactivities. In particular, the importance of integrating meaningful and activeaspects into the educational process is speculated upon.

This article focuses on the study of hierarchical lexical-semantic (terminological) fields dental discourse in terms of comparative paradigms based on the Russian and English languages. Modern medical terminology is characterized as a system of medical and paramedical terms resulting from centuries-old development of world healing. Cognitive communication the space of dentistry accumulates a universal general language, general medical information, based on the prevailing medical terminology fund, the core of medical terminology, and narrowly professional information, forming a wide peripheral a structure representing specific professional knowledge, due to a change in the scientific picture of the world.

Softening of piezoelectric materials facilitates the development of flexible wearables and energy harvesting devices. However, as one of the most competitive candidates, piezoelectric ceramic-polymer composites inevitably exhibit reduced power-generation capability and weak mechanical strength due to the mismatch of strength and permittivity between the two phases inside. Herein a flexible, air-permeable, and high-performance piezoceramic textile composite with a mechanically reinforced hierarchical porous structure is introduced. Based on a template-assisted sol-gel method, a three-order hierarchical ceramic textile is constructed by intertwining submillimeter-scale multi-ply ceramic fibers that are further formed by twisting micrometer-scale one-ply ceramic fibrils. Theoretical analysis indicates that large mechanical stress can be easily induced in the multi-order hierarchical structure, which greatly benefits the electrical output. Fabricated samples generate an open-circuit voltage of 128 V, a short-circuit current of 120 µA, and an instantaneous power density of 0.75 mW cm−2, much higher than the previously reported works. The developed multi-order and 3D-interconnected piezoceramic textile shows satisfactory piezoelectricity (d33 of 190 pm V−1), air permeability (45.1 mm s−1), flexibility (Young's modulus of 0.35 GPa), and toughness (0.125 MJ m−3), collectively. The design strategy of obtaining balanced properties promotes the practicality of smart/functional materials in wearables and flexible electronics. © 2021 Wiley-VCH GmbH.

The use of plant proteins to design colloidal food systems is a hot topic in the current context of the protein transition. However, replacing animal-derived proteins (in particular, dairy proteins) that have been traditionally used for this purpose by plant proteins is a challenge from various perspectives, and in particular, because of drastically different solubility and functionality. A possible route to mitigate these issues is to combine plant and dairy proteins, providing that their interactions can be understood from the molecular to the macroscopic scale. This review addresses the major advances that have occurred in the field of such blend-based systems, all the way from their behaviour in aqueous dispersions to their potential applications in gels, foams and emulsions.

If robots can merge the appearance-based place knowledge of other robots with their own, they can relate to these places even if they have not previously visited them. We have investigated this problem using robots with compatible visual sensing capabilities and with each robot having its individual long-term place memory. Here, each place refers to a spatial region as defined by a collection of appearances and in the place memory, the knowledge is organized in a tree hierarchy. In the proposed merging approach, the hierarchical organization plays a key role—as it corresponds to a nested sequence of hyperspheres in the appearance space. The merging proceeds by considering the extent of overlap of the respective nested hyperspheres—starting with the largest covering hypersphere. Thus, differing from related work, knowledge is merged in as large chunks as possible while the hierarchical structure is preserved accordingly. As such, the merging scales better as the extent of knowledge to be merged increases. This is demonstrated in an extensive set of multirobot experiments where robots share their knowledge and then use their merged knowledge when visiting these places., QC 20200707

Understanding the magnetic properties of nanostructures is a field under continuous evolution. Not only the low-dimensional characteristics of the materials confer unique properties to those structures, but also the high degree of freedom when fabricating them increases the possibilities of tailoring their magnetic properties. The recent development of novel technologies that provide ways of both fabrication and characterization at the nanoscale have opened door to the obtainment of nanostructures with specifically designed magnetic properties. In this chapter we have reviewed some of these tailored nanostructures that are sometimes referred to as three-dimensional (3D) nanostructures, such as diameter-modulated nanowires and composition-modulated nanowires. Then, we compare these structures to actual 3D nanostructures, that is, those that take advantage of their design in three spatial dimensions. Finally, we discuss in depth one fascinating 3D self-sustained magnetic nanostructure which has been developed within our research group based on template grown inside 3D tailored alumina, which is obtained using only industrially scalable and highly tunable fabrication methods.

Functional surfaces have been investigated widely due to different applications in industries. In this paper, the surface functionality was the contrast generated by surfaces orthogonally textured with micro ridges. The principle to generate contrast was the anisotropic reflection led by the bevel surfaces of micro ridges. The surface quality of the micro bevels determined the reflection of the features. In the authors' previous work, such a functionality was successfully achieved on flat and cylinder surfaces of tool steel samples by micro milling. However, due to the limitation of micro milling process for microstructure fabrication, this study investigated the manufacturing of 3D functional surfaces of RSA 905 by diamond engraving. The 3D surface was shaped with hierarchical structures of micro bricks and micro ridges on the bricks: the surface was divided into micro grids then each grid was machined into a flat basic cell by using a round-tipped tool; the micro ridges were engraved on the basic cells with a sharp-tipped tool. In order to determine the feasibility of the microstructures to achieve contrast generation on 3D surfaces, a data matrix consisting of such micro ridges was patterned on a spherical concave and a freeform surface. The surface integrity was evaluated by measuring the surface roughness of the bevels on the micro ridges, characterizing the burr formation and detection of possible defects left on the micro features that affect the surface functionality. The successful scanning of the data matrix proved the microstructures successfully generated enough contrast to form readable codes. Furthermore, the contrast generated by the microstructures was quantified for process optimization by using a customized robotic measuring system.

Image classification models built into visual support systems and other assistive devices need to provide accurate predictions about their environment. We focus on an application of assistive technology for people with visual impairments, for daily activities such as shopping or cooking. In this paper, we provide a new benchmark dataset for a challenging task in this application – classification of fruits, vegetables, and refrigerated products, e.g. milk packages and juice cartons, in grocery stores. To enable the learning process to utilize multiple sources of structured information, this dataset not only contains a large volume of natural images but also includes the corresponding information of the product from an online shopping website. Such information encompasses the hierarchical structure of the object classes, as well as an iconic image of each type of object. This dataset can be used to train and evaluate image classification models for helping visually impaired people in natural environments. Additionally, we provide benchmark results evaluated on pretrained convolutional neural networks often used for image understanding purposes, and also a multi-view variational autoencoder, which is capable of utilizing the rich product information in the dataset., QC 20190611

Hydrogen is a source of sustainable and clean energy poised to replace fossil fuels. Bifunctional electrocatalysts are actively pursued to simultaneously drive the two key reactions, hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), for hydrogen production by electrolysis water. One of the most promising candidates based on bimetallic layered double hydroxide salts (LHSs) and cobalt-based organic framework (ZIF-67) suffer from poor interface coupling. Herein, we present a new approach based on fusing NiCo LHSs nanowire arrays with ZIF-67 to fabricate three-dimensional flower-like structures on a Ni-Fe foam support. To improve interfacial coupling and catalytic performance, simple oxidation, carbonization, sulfurization, and selenization are performed to study the effects of different post-treatments and discover the optimum bifunctional electrocatalysts. The optimized S-doped catalyst reveals the highest electrocatalytic characteristic quantified by the low overpotentials of 170 and 100 mV for OER and HER at 10 mA cm -2 in 1 M KOH, respectively. This outstanding electrocatalytic property is ascribed to strong interfacial coupling between the NiCo-LHSs and ZIF-67 derivatives, as well as the rational electronic structures, dense catalytic active sites, and large specific surface area. This work opens new prospects for fabricating efficient and low-cost electrocatalysts for renewable hydrogen energy production.

Image classification models built into visual support systems and other assistive devices need to provide accurate predictions about their environment. We focus on an application of assistive technology for people with visual impairments, for daily activities such as shopping or cooking. In this paper, we provide a new benchmark dataset for a challenging task in this application – classification of fruits, vegetables, and refrigerated products, e.g. milk packages and juice cartons, in grocery stores. To enable the learning process to utilize multiple sources of structured information, this dataset not only contains a large volume of natural images but also includes the corresponding information of the product from an online shopping website. Such information encompasses the hierarchical structure of the object classes, as well as an iconic image of each type of object. This dataset can be used to train and evaluate image classification models for helping visually impaired people in natural environments. Additionally, we provide benchmark results evaluated on pretrained convolutional neural networks often used for image understanding purposes, and also a multi-view variational autoencoder, which is capable of utilizing the rich product information in the dataset., QC 20190611