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Directed self‐assembly of materials into patterned structures is of great importance since the performance of them depends remarkably on their multiscale hierarchical structures. Therefore, purposeful structural regulation at different length scales through crystallization engineering provides an opportunity to modify the properties of polymeric materials. Here, an epitaxy‐directed self‐assembly strategy for regulating the pattern structures including phase structure as well as crystal modification and orientation of each component for both copolymers and polymer blends is reported. Owing to the specific crystallography registration between the depositing crystalline polymers and the underlying crystalline substrate, not only order phase structure with controlled size at nanometer scale but also the crystal structure and chain orientation of each component within the separated phases for both copolymers and polymer blend systems can be precisely regulated. [ABSTRACT FROM AUTHOR]

Abstract Directed self‐assembly of materials into patterned structures is of great importance since the performance of them depends remarkably on their multiscale hierarchical structures. Therefore, purposeful structural regulation at different length scales through crystallization engineering provides an opportunity to modify the properties of polymeric materials. Here, an epitaxy‐directed self‐assembly strategy for regulating the pattern structures including phase structure as well as crystal modification and orientation of each component for both copolymers and polymer blends is reported. Owing to the specific crystallography registration between the depositing crystalline polymers and the underlying crystalline substrate, not only order phase structure with controlled size at nanometer scale but also the crystal structure and chain orientation of each component within the separated phases for both copolymers and polymer blend systems can be precisely regulated.

Based on the non-equilibrium Green's function theory, the quantum transport characteristics in zigzag graphene nanoribbons with triangular patterned structure have been explored. The results show that the local states caused by the patterned structure can cause the coupling between the edge states of graphene nanoribbons, which leads to the sharp destruction of the step structure of the tunneling conductance of the structure. For a certain incident energy and patterned structure, we can obtain a fully polarized spin current in antiferromagnetic nanoribbons. In addition, in the low-energy region, the different orientations of triangular patterned structure can also modulate the tunneling conductance of the structure. The proposal is experimentally feasible and will be helpful for exploring the design of graphene nanoribbon-based electronic devices. [ABSTRACT FROM AUTHOR]

Patients who suffer from traumatic brain injury (TBI) often complain of learning and memory problems. Their symptoms are principally mediated by the hippocampus and the ability to adapt to stimulus, also known as neural plasticity. Therefore, one plausible injury mechanism is plasticity impairment, which currently lacks comprehensive investigation across TBI research. For these studies, we used a computational network model of the hippocampus that includes the dentate gyrus, CA3, and CA1 with neuronscale resolution. We simulated mild injury through weakened spike-timingdependent plasticity (STDP), which modulates synaptic weights according to causal spike timing. In preliminary work, we found functional deficits consisting of decreased firing rate and broadband power in areas CA3 and CA1 after STDP impairment. To address structural changes with these studies, we applied modularity analysis to evaluate how STDP impairment modifies community structure in the hippocampal network. We also studied the emergent function of network-based learning and found that impaired networks could acquire conditioned responses after training, but the magnitude of the response was significantly lower. Furthermore, we examined pattern separation, a prerequisite of learning, by entraining two overlapping patterns. Contrary to our initial hypothesis, impaired networks did not exhibit deficits in pattern separation with either population- or rate-based coding. Collectively, these results demonstrate how a mechanism of injury that operates at the synapse regulates circuit function. [ABSTRACT FROM AUTHOR]

Patients who suffer from traumatic brain injury (TBI) often complain of learning and memory problems. Their symptoms are principally mediated by the hippocampus and the ability to adapt to stimulus, also known as neural plasticity. Therefore, one plausible injury mechanism is plasticity impairment, which currently lacks comprehensive investigation across TBI research. For these studies, we used a computational network model of the hippocampus that includes the dentate gyrus, CA3, and CA1 with neuron-scale resolution. We simulated mild injury through weakened spike-timing-dependent plasticity (STDP), which modulates synaptic weights according to causal spike timing. In preliminary work, we found functional deficits consisting of decreased firing rate and broadband power in areas CA3 and CA1 after STDP impairment. To address structural changes with these studies, we applied modularity analysis to evaluate how STDP impairment modifies community structure in the hippocampal network. We also studied the emergent function of network-based learning and found that impaired networks could acquire conditioned responses after training, but the magnitude of the response was significantly lower. Furthermore, we examined pattern separation, a prerequisite of learning, by entraining two overlapping patterns. Contrary to our initial hypothesis, impaired networks did not exhibit deficits in pattern separation with either population- or rate-based coding. Collectively, these results demonstrate how a mechanism of injury that operates at the synapse regulates circuit function.

Functional nanoparticles (NPs) with unique photoelectric, mechanical, magnetic, and chemical properties have attracted considerable attention. Aggregated NPs rather than individual NPs are generally required for sensing, electronics, and catalysis. However, the transformation of functional NP aggregates into scalable, controllable, and affordable functional devices remains challenging. Printing is a promising additive manufacturing technology for fabricating devices from NP building blocks because of its capabilities for rapid prototyping and versatile multifunctional manufacturing. This paper reviews recent advances in NP patterning based on the combination of self-assembly and printing technologies (including two-, three-, and four-dimensional printing), introduces the basic characteristics of these methods, and discusses various fields of NP patterning applications. Public summary: • Nanoparticles (NPs) printing assembly is a good solution for patterned devices • NPs assembly can be combined with 2D, 3D, and 4D printing technologies • A variety of ink-dispersed NPs are available for printing assembly • NPs printing assembly technology is applied for nanosensing, energy storage, photodetector

In this paper, novel and stable acetylcholinesterase (AChE) sensor with patterned structure for detecting organophosphorus pesticides (OPs) based on titanium dioxide sol‐gel carrier was proposed and prepared. Biosensor was assembled by dropping titanium oxide, chitosan (CS) and enzyme to the surface of the glass carbon step by step. The concentration range of the sensor detection for dichlorvos (DDVP) is 1.13 nM to 22.6 μM, and the limit of detection (LOD) is 0.23 nM. It can also detect dichlorvos in cabbage juice samples accurately. The preparation of biosensor adopted a patterned novel structure for the first time, which opens a new way for the structure optimization of organophosphorus pesticide sensor. [ABSTRACT FROM AUTHOR]

The rational design of electrochemically and mechanically stable Si anodes is of great importance for the development of high energy density lithium‐ion batteries. In this study, patterned Si‐based (Si/ZnO/C) trilayer composite films were synthesized by magnetron sputtering with the assistance of a patterned mask. The electron‐conductive C layer at the top of the composite film is deposited to enhance the interfacial stability between active film and electrolyte. The ion‐ and electron‐conductive Li2O–Zn middle layer can be ingeniously introduced by means of the poor reversed conversion reaction between ZnO and Li+ ions after the first cycle. The resultant Si/Li2O–Zn/C trilayer composite film delivers a high reversible capacity of 1536 mAh g−1 after 800 cycles at a current density of 1.0 A g−1 and a long high‐rate cycling stability (1400 mAh g−1 after 6000 cycles even at a high current density of 10.0 A g−1). Excellent rate capability and improved Coulombic efficiency are also achieved. The influences of the patterned structure and each modified layer on the electrochemical properties are analyzed systematically. This work offers a new and promising direction to enhance the lithium‐storage properties of Si‐based thin‐film anodes. Trilayer patterned films: Synthesis of a Si‐based (Si/Li2O–Zn/C) trilayer composite film by magnetron sputtering is presented (see figure). The trilayer composite film delivers a high reversible capacity of 1536 mAh g−1 after 800 cycles at a current density of 1.0 A g−1 and a long high rate cycling stability (1400 mAh g−1 after 6000 cycles even at a high current density of 10.0 A g−1). [ABSTRACT FROM AUTHOR]

For environmental applications, such as water and air purification utilizing photocatalysts, we synthesized patterned titanium dioxide (TiO2) thin films using polystyrene (PS) spheres. This was primarily done to enhance the surface area and photocatalytic activities. TiO2 thin films were deposited on silicon wafers attached to variously sized PS spheres via the spin coating method and were annealed at 600 °C. The processing step involved patterning and coating a TiO2 sol–gel. The photocatalytic performance was analyzed using an UV–visible spectrophotometer. Within 20 min, a high catalytic efficiency (98% removal) with a 20-time faster decomposition rate of the malachite green (MG) solution than that of the nonpatterned TiO2 was obtained from the patterned TiO2 with 400 nm sized PS due to the large surface area. In addition, the phenol in the water removed as much as 50% within 2 h with the same photocatalyst, which was expected to be one of the strong candidates to be applied to the next generation of photocatalysts for water purification.

Using the hybrid self-consistent field and density functional theories, we investigate the self-assembling behavior of nanoparticle-polymer mixtures confined in square-pillar arrays. By varying the volume fraction of nanoparticles and the sizes of the system and the pillar, various patterned structures are achieved. The predicted structures can be reasonably comprehended by the competition between entropy and enthalpy of nanoparticles and polymers. The results play an important role in understanding array confinement and provide a helpful guidance for designing the functionally useful microstructures. [ABSTRACT FROM AUTHOR]

• Orientational Au NBPs patterned structures were constructed as plasmonic materials. • The plasmonic properties of patterned structures were explored. • The polarized ECL was regulated by the direction of patterned structures. • The polarization-resolved ECL was used to analyze miRNA expression level. Here, we developed a polarization-resolved surface plasmon coupling electrochemiluminescence (ECL) strategy based on orientational Au nanobipyramids (Au NBPs) patterned structures. As the surface plasmonic materials, the Au NBPs with large localized electromagnetic field enhancement were used to construct the different patterned structures through the droplet evaporation induced assembly. The distinct morphology of the horizontal and vertical Au NBPs patterned structures provided the different plasmonic properties reflecting on resonance peak positions and polarized absorbance. As a result, the variations of the polarized ECL emission of SnS 2 QDs have been regulated by the Au NBPs patterned structures via the surface plasmon coupling progress. Because of the superior polarization-resolved ECL performances, the sensing system was used to analyze the miRNA-21 and miRNA-205 expression level in tumor tissues of triple negative breast cancer patients. The satisfactory results indicated this polarization-resolved sensing strategy possessed great potential for clinical analysis. [ABSTRACT FROM AUTHOR]

As its title indicates, Hong Sang-soo's filmOn the Occasion of Remembering the Turning Gate(Saeng-hwal-eui Bal-gyun) (2002) refers to a specific Chinese legend whose conclusion is alluded to at the end of the film. Though there are apparent references to the legend in the film's first half, the allusions there seem to have no immediate purpose. However, in light of the general pattern of reversibility that structures much of the film, those apparent references in conjunction with some dances early in the film suggest that the allusions refer, not to the Chinese legend, but rather to a well-known Japanese Kabuki play, A Maiden at Dōjōji, whose action inverts gendered roles of the Chinese legend. [ABSTRACT FROM AUTHOR]

Highlights: [•] We review our recent results on the formation of patterned structures of particles. [•] We use a bottom-up self-assembly process for the pattern formation. [•] The self-assembly process produces various patterns on a completely flat substrate. [•] The microstructure of particles varies depending on the macroscopic parameters. [•] The self-assembly process forms a template-free technique for pattern formation. [Copyright &y& Elsevier]

Functional nanoparticles (NPs) with unique photoelectric, mechanical, magnetic, and chemical properties have attracted considerable attention. Aggregated NPs rather than individual NPs are generally required for sensing, electronics, and catalysis. However, the transformation of functional NP aggregates into scalable, controllable, and affordable functional devices remains challenging. Printing is a promising additive manufacturing technology for fabricating devices from NP building blocks because of its capabilities for rapid prototyping and versatile multifunctional manufacturing. This paper reviews recent advances in NP patterning based on the combination of self-assembly and printing technologies (including two-, three-, and four-dimensional printing), introduces the basic characteristics of these methods, and discusses various fields of NP patterning applications., Competing Interests: The authors declare no competing interests., (© 2022 The Authors.)

Abstract: High emissivity coatings have been widely used in many high temperature applications. Here we report a novel structure of magnetron sputtering silicon carbide (SiC) films on Ni photonic crystals (PCs) to improve emissivity performance. It is found that SiC coatings reveal two-dimensional patterned structures due to their preferential growth on the skeleton of Ni PCs. The spectral emissivity results show periodic structures and surface-porous structured SiC can enhance the coatings’ spectral emissivity because of higher rough surface, lower reflectivity and magnitude of thermal fluctuations. The method holds promising potential for preparing a series of high emissivity coatings and highly ordered metal–ceramics composites microstructures for thermophotovoltaic (TPV) radiator, pyroelectric and other photonics applications. [Copyright &y& Elsevier]

The initial stage of liquid absorption in unsaturated nonwoven fabrics (e.g. dry wipes, absorbent materials and hygiene products) is an unsteady-state fluid flow. For the purpose of the engineering design of these nonwoven products, there is a need to predict the unsteady-state fluid flow in both homogeneous anisotropic nonwoven structures and heterogeneous patterned nonwoven fabrics having a dual-scale porosity structure. In this paper, the unsteady-state liquid wicking in homogeneous anisotropic nonwoven fabric structure has been modeled, and the relationship between unsteady-state liquid absorption in patterned nonwoven fabrics and its structural parameters has been established based on the fabric structural parameters. [ABSTRACT FROM AUTHOR]

For environmental applications, such as water and air purification utilizing photocatalysts, we synthesized patterned titanium dioxide (TiO2) thin films using polystyrene (PS) spheres. This was primarily done to enhance the surface area and photocatalytic activities. TiO2 thin films were deposited on silicon wafers attached to variously sized PS spheres via the spin coating method and were annealed at 600 °C. The processing step involved patterning and coating a TiO2 sol–gel. The photocatalytic performance was analyzed using an UV–visible spectrophotometer. Within 20 min, a high catalytic efficiency (98% removal) with a 20-time faster decomposition rate of the malachite green (MG) solution than that of the nonpatterned TiO2 was obtained from the patterned TiO2 with 400 nm sized PS due to the large surface area. In addition, the phenol in the water removed as much as 50% within 2 h with the same photocatalyst, which was expected to be one of the strong candidates to be applied to the next generation of photocatalysts for water purification. [ABSTRACT FROM AUTHOR]

Wearable devices with integrated alarm functions play a vital role in daily life and can help people prevent potential hazards. Although many wearable sensors have been extensively studied and proposed to monitor various physiological signals, most of them are needed to integrate with the external alarm elements to realize warning, such as light-emitting diodes and buzzers, resulting in the system complexity and poor flexibility. In this paper, an integrated sensing and warning multifunctional device based on the mechanical and thermal effect of porous graphene is proposed on a bilayer asymmetrical pattern of laser-induced graphene (LIG). Compared with the strain sensor with nonpatterned LIG, the mechanical performance is greatly improved with the highest gauge factor value of up to 950 for the strain sensor with mesh-patterned LIG. On the contrary, the heating performance of the heater with nonpatterned LIG is better than that with mesh-patterned LIG. Combining the performance differences of different LIG patterns, the integrated wearable device with a bilayer asymmetrical LIG pattern is demonstrated. It can generate enough heating energy to warn the person when the detected signal meets the threshold condition measured in real time by the ultrasensitive strain sensor. This work will provide a new way to construct an integrated wearable device for realizing multifunctional applications. This integrated multifunctional device shows great potential toward the applications in healthcare monitoring and timely warning.

We report classical and replica exchange molecular dynamics simulations that establish the mechanisms underpinning the growth kinetics of a binary mix of nanorings that form striped nanotubes via self-assembly. A step-growth coalescence model captures the growth process of the nanotubes, which suggests that high aspect ratio nanostructures can grow by obeying the universal laws of self-similar coarsening, contrary to systems that grow through nucleation and elongation. Notably, striped patterns do not depend on specific growth mechanisms, but are governed by tempering conditions that control the likelihood of depropagation and fragmentation.