Heterogeneous Templates Research Articles

Sentiments of solidarity: Varying conceptions of nationhood in Turkey

AbstractStudies on nationalism have recently transitioned from macro‐level analyses of large structural factors to micro‐level examinations, emphasizing nationalism as a set of cultural and political beliefs held by individuals. Such works that use opinion measures to explore heterogeneity in national self‐understandings show that nationalist beliefs distribute among the public in particular and non‐random ways, though the extent to which these heterogeneities induce variation in behavioural outcomes remains relatively unexplored. In this article, we argue that varying conceptions of nationhood inform ethnonational boundary‐making strategies and social action. Using latent class analyses and a resource allocation task in original representative survey data (N = 1,460), we ask whether varying cultural positions on nationhood covaries with preferential behaviour. We found that nationalist cultural models provide heterogeneous cultural templates and lead to preferential treatment of ethnonational ingroups.

Ultra-high electro-strain and low hysteresis lead-free piezoelectric ceramics obtained by a novel texture engineering strategy

Two problems plague the field of electro-strain research: low electro-strain performance and high hysteresis. These two key factors are often difficult to optimise simultaneously. Therefore, a novel texture engineering strategy is proposed to obtain ultra-high strain while effectively reducing strain hysteresis. Synergistically optimized textured ceramics with a high degree of orientation in <001> direction were achieved by improving the preparation process based on the conventional TGG method through a heterogeneous template distinct from the ceramic substrate. Finally, the normalized strain of 951 pm/V at 40 kV/cm is obtained in the BNT-based lead-free system, and the strain hysteresis is only 43 %. At the same time, a series of in-situ electric field structural characterization reveal the source of high strain and low hysteresis of the textured ceramics: heterogeneous templates caused high polarization and formed a large number of PNRs. This result is of great significance for the study of electro-strain in lead-free piezoelectric materials and the development of actuators.

Development of Molecularly Imprinted Polymer Nanoparticles with High Affinity and Its Application to Electrochemical Biosensors

Molecularly imprinted polymers (MIPs) have the potentials to be low-cost and stable alternatives to natural receptors such as enzymes and antibodies for biosensors. In our group, we have been developing enzyme-/antibody-free electrochemical biosensors with the MIP-coated electrodes [1,2]. However, the conventional polymerization methods for MIPs have the limitations such as their heterogeneities that reduce high binding affinity sites and the presence of residual templated molecules, which are detrimental to biomolecular recognition. To address these issues, we have synthesized molecularly imprinted polymer nanoparticles (nano-MIPs) with virtually free of heterogeneous templates and higher affinity for target biomolecules by using a solid-phase approach synthesis method [3]. In this study, we have focused on the biomarkers such as human serum albumin (HSA) and glycated albumin (GA) for diabetes and then synthesized the redox-labeled HSA-templated nano-MIPs (HNMs) and GA-templated nano-MIPs (GNMs) for the electrochemical biosensor (Figure 1). The fundamental characteristics of HNMs and GNMs such as chemical composition, particle size, and binding affinity have been evaluated by using proton nuclear magnetic resonance (1H NMR), dynamic light scattering (DLS), atomic force microscopy (AFM), cyclic voltammetry (CV), isothermal titration calorimetry (ITC), and surface plasmon resonance (SPR).References Kajisa, T.; Sakata, T. ACS Appl. Mater. Interfaces 2018,10, 34983–34990.Sakata, T.; Nishitani, S.; Kajisa, T. RSC Advances 2020, 10, 16999–17013.Canfarotta, F. et al. Nat. Protoc. 2016, 3, 443-455. Figure 1

Protein crystallization with DNA templates

Protein crystallization plays a significant role in three-dimensional structural analysis and protein purification. It is important to increase the crystallization efficiency, which is possible by adding heterogeneous templates in crystallization systems. DNA is biologically compatible and artificially designable polymer, which is easy to extract. In this study, single- and double-stranded DNA of precise sequences were designed and used as templates to promote protein crystallization of lysozyme and catalase. Influence of DNA, single-stranded DNA with 10, 20, 40 bases and double-stranded DNA with 10, 20, 40 base pairs, were investigated. The success rate of obtaining crystals of lysozyme and catalase in equal period was significantly improved with the addition of DNA comparing without templates added. Double-stranded DNA led to higher nucleation rate than that with single-stranded DNA. The promotion of nucleation was more obvious at low concentration of protein solution and with longer chain DNA templates. Crystal number and crystallization rate was enhanced with addition of long double-stranded DNA templates. All the results confirm that DNA is an effective polymer additive to enhance protein crystallization, especially for the application of the scarce protein crystallization.

Effect of nanocomposite pour point depressant EVAL/CNT on flow properties of waxy crude oil

The nanocomposite EVAL-CNT was produced by chemical grafting in the solution system through the esterification of ethylene-vinyl alcohol copolymer (EVAL) and carboxylated multi-walled carbon nanotubes (O-MWCNT), and its structural properties were characterized. The improvement of the rheological properties of the waxy oil system by the novel pour point depressant was investigated using macroscopic rheological measurements and microscopic observations. The results showed that EVAL-CNT nanocomposite pour point depressant (PPD) could significantly reduce the pour point and improve the low temperature fluidity of crude oil and had better performance than EVAL-GO at the same addition level. The best effect was achieved at the dosing concentration of 400 ppm, which reduced the pour point by 13 °C and the low-temperature viscosity by 85.4%. The nanocomposites dispersed in the oil phase influenced the precipitation and crystallization of wax molecules through heterogeneous crystallization templates, which led to the increase of wax crystal size and compact structure and changed the wax crystal morphology, which had a better effect on the rheological properties of waxy oil.

Positive and negative effects of graphite flake and monolayer graphene oxide templates on protein crystallization

Heterogeneous template-induced nucleation is a promising way to regulate protein crystallization events and could be employed for purification processes and crystallographic studies. Protein crystallization process with graphite and graphene oxide, as heterogeneous templates, were investigated. More than 640 hanging drops with different concentrations of Lysozyme (30, 50, 70, 100 mg/mL) and NaCl (0.7, 0.9, 1.1, 1.3, 1.5 M) were crystallised at 4 °C with or without graphite/graphene oxide templates. The induction times and crystallization process were observed under the microscope. The lysozyme in the solutions with graphite flakes nucleated faster under all the conditions than the lysozyme with equal experimental conditions without templates. The crystals preferred to grow around the edge of graphite flakes than on the flat surfaces. In the droplets with monolayer graphene oxide, more crystals appeared around graphene oxide particles, and the faster or slower nucleation processes with templates were dependent on the lysozyme and NaCl concentrations. Graphene oxide templates strongly inhibited nucleation at high lysozyme concentrations but promoted nucleation at low lysozyme concentrations. Both heterogeneous templates changed the crystal morphology and the crystallization kinetics. More crystals were observed in the solution with graphite templatesthan with graphene oxide templates and without any template.

Single CdSe Quantum Dots Positioned in Nanostructured Heterogeneous Templates: Implications for High-Precision Nanoassembly

Single CdSe Quantum Dots Positioned in Nanostructured Heterogeneous Templates: Implications for High-Precision Nanoassembly

Programmed Assembly of DNA Templates by Silver Nanowires.

DNA origami templates are known to exhibit many advantages to integrate functional components at desirable locations for nanoelectronic applications. In order to immobilize conducting or semiconducting species in a bottom-up approach, the programmed assembly of DNA templates is of utmost necessity. This report demonstrates the silver nanowires enabled bridging of two linear DNA origami (DO) nanostructures by utilizing the host-guest interaction of biotin-STV and sequence-specific silver metallization of poly(dG-dC) DNA nanowires (in 10 % yield) using (dA)10 coated AgNPs (15 nm). The enzymatic synthesis of 750 bp, 1500 bp and 3000 bp bis-biotinylated poly(dG-dC), facile synthesis of 1 : 1 biotin-STV and silver-nanowire bridged DNA templates were characterized by gel electrophoresis, atomic force microscope imaging techniques. The strategy utilized here provides a method that can precisely connect heterogeneous templates towards bottom-up fabrication of practical nanoelectronics.

Achieving high piezoelectric performances with enhanced domain-wall contributions in -textured Sm-modified PMN-29PT ceramics

1% Sm substituted PMN-29PT ([Sm0.01Pb0.985][(Mg1/3Nb2/3)0.71Ti0.29]O3) textured ceramics with a Lotgering factor of up to 80 % were successfully prepared. The dielectric, ferroelectric and piezoelectric properties have been investigated in detail for both textured and non-textured ceramics. The heterogeneous templates are found to be critical for the change in relaxor behaviors, leading to the reduced Tf, Tm, εmax and Pr in textured ceramics. The textured ceramics show an enhanced d33 of 810 pC/N, about 1.6 times greater than their randomly oriented ceramic counterparts. The domain structures and their responses to applied electric fields have been studied using piezoresponse force microscopy, signifying the enhanced extrinsic contributions by the increased domain wall densities and dynamics. The improved dielectric and piezoelectric properties are discussed and explained from the view point of extrinsic contributions in textured ceramics. The results demonstrate that the textured Sm-PMN-PT piezoelectric ceramics could be promising high performance piezoelectrics with low cost.

Supersaturation Dependent Separation of Vanillin Polymorphs from Aqueous Solution in the Presence of Ni‐Foam as Template

AbstractA unique approach of employing heterogeneous templates for the polymorphic nucleation of vanillin is investigated for the first time using swift cooling crystallization process. The template surface with respect to the intense of supersaturation imparts great difference on the nucleation and morphology of vanillin polymorphs. Thus using Ni‐foam as a novel metal template, both the stable and metastable polymorphs of vanillin are isolated via template‐induced heterogeneous nucleation. The introduction of template plays dual role that induces the nucleation of rare metastable polymorph of vanillin and controls the liquid–liquid phase separation. Moreover, the internal structures and thermal behaviors of the obtained polymorphs are carefully characterized using powder X‐ray diffraction, single crystal X‐ray diffraction, and differential scanning calorimetry analyses, respectively. As a result, the template‐induced heterogeneous nucleation is observed to be a favorable technique for the separation of polymorphic forms of vanillin.

Contrasting Chemistry of Block Copolymer Films Controls the Dynamics of Protein Self-Assembly at the Nanoscale.

Biological systems are able to control the assembly and positioning of proteins with nanoscale precision, as exemplified by the intricate molecular structures within cell membranes, virus capsids, and collagen matrices. Controlling the assembly of biomolecules is critical for the use of biomaterials in artificial systems such as antibacterial coatings, engineered tissue samples, and implanted medical devices. Furthermore, understanding the dynamics of protein assembly on heterogeneous templates will ultimately enable the control of protein crystallization in general. Here, we show a biomimetic, hierarchical bottom-up approach to direct the self-assembly of crystalline S-layers through nonspecific interactions with nanostructured block copolymer (BCP) thin-film templates. A comparison between physically and chemically patterned BCP substrates shows that chemical heterogeneity is required to confine the adhesion and self-assembly of S-layers to specific BCP domains. Furthermore, we show that this mechanism can be extended to direct the formation of collagen fibers along the principal direction of the underlying BCP substrate. The dynamics of protein self-assembly at the solid-liquid interface are followed using in situ high-resolution atomic force microscopy under continuous flow conditions, allowing the determination of the rate constants of the self-assembly. A pattern of alternating, chemically distinct nanoscale domains drastically increases the rate of self-assembly compared to non-patterned chemically homogeneous substrates.

Mechanistic Study of Galvanic Replacement of Chemically Heterogeneous Templates

Galvanic replacement is a useful method for synthesizing architecturally complex multimetallic nanostructures from monometallic templates. The oxidation of monometallic templates by ions of a more noble metal is well-studied; however, chemically heterogeneous templates offer more than one type of reaction site and potentially structurally more complex materials. Yet, mechanistic studies with such templates are limited. Here, the reactivities of Ag and Pd in Janus-style AgPd dimers are compared when ions capable of oxidizing both metals are introduced. This study reveals (1) the selectivity of galvanic replacement with dimer templates, (2) cooperativity between galvanic replacement in one dimer domain and solid-state diffusion in another domain, and (3) similar replacement mechanisms for different redox pairs. Specifically, Au ions almost exclusively replace Ag before exchange with Pd is evident, and Ag oxidation facilitates diffusion of the remaining Ag into the Pd domain. These results provide mechanisti...

Poly(aminopropyl/methyl)silsesquioxane microspheres improve the flowability of model waxy oils associated with asphaltenes

In this article, poly(aminopropyl/methyl)silsesquioxane (PAMSQ) microspheres with different polarities were first synthesized and characterized. The polarity of the PAMSQ microspheres is progressively enhanced by increasing the aminopropyl molar ratios (1–25 mol%). Then, the effect of PAMSQ microspheres with different polarities on the flowability of the model waxy oils with/without asphaltenes was studied through rheological tests, DSC analyses, microstructure observation and asphaltenes precipitating measurement. The results indicated the PAMSQ microspheres alone could spacially hinder the interactions among the precipitated paraffin crystals, thus slightly improving the flowability of the model waxy oil without asphaltenes (MO-1). The improving ability of PAMSQ microspheres deteriorates with the polarity increasing, and the MO-1 shows the best flowability after adding 200 ppm PAMSQ-1 microsphere (with the aminopropyl molar ratio at 1 mol%). To our surprise, adding PAMSQ microspheres can significantly improve the flow behavior of the model waxy oil with 0.75 wt% asphaltenes (MO-2). Based on the asphaltenes precipitation data, the PAMSQ microspheres could adsorb asphaltenes to form the PAMSQ/asphaltene composite particles in MO-2. The composite particles can play a role of the heterogeneous nucleation templates for paraffin molecules and facilitate the formation of larger and more compact wax floccules, thus enhancing the flowability of MO-2 at low temperatures. The flow improving ability of the PAMSQ microspheres for MO-2 increases with increasing the polarity of the microspheres due to the increased interactions between the microspheres and asphaltenes. The MO-2 exhibits the best flowability after adding 200 ppm PAMSQ-3 microsphere (with aminopropyl molar ratio at 15 mol%). When the polarity of the microspheres is too strong (PMASQ-4 microsphere), however, the microspheres cannot dispersed in waxy oil stably, thus inhibiting the interactions between the microspheres and asphaltenes and deteriorating the flow improving ability of the microspheres for MO-2.

Support-free nanostructured Pt[sbnd]Cu electrocatalyst for the oxygen reduction reaction prepared by alternating magnetron sputtering

Nanostructuring of electrocatalysts is an important aspect of catalyst design as catalytic performance depends not only on the specific activity (reaction rate per surface area), but also on the dispersion of the catalyst. We present an industrially compatible, but effective preparation method for support-free nanostructured catalyst layers. Alternating sputtering was used to prepare heterogeneous PtCu templates ranging from 95 up to 99.5 at. % Cu. These templates were then electrochemically leached to form a nanostructured PtCu network and benchmarked with respect to the oxygen reduction reaction. It is shown that the templates with lower Cu:Pt ratios exhibit the highest initial specific activity but have a relatively low electrochemically active surface area. Subjecting the samples to extended accelerated stress tests, it is found that the support-free nanostructured PtCu networks are relatively resistant to high potential cycling, which can be explained by the lack of carbon corrosion. The loss in electrochemical surface area thereby depends on the initial Pt content. The specific oxygen reduction activity, however, approaches the value of bulk Pt. Although this decrease is not desirable, still an (specific) activity improvement of two to four times as compared carbon supported nanoparticles can be preserved.

Morphology-controlled synthesis of polymethylsilsesquioxane (PMSQ) microsphere and its applications in enhancing the thermal properties and flow improving ability of ethylene-vinyl acetate copolymer

Here, we reported that by adjusting the stirring speed, condensation pH value, precursor concentration and reaction temperature, the morphologies of the polymethylsilsesquioxane (PMSQ) microsphere could be well controlled through the two-step sol-gel synthesis. Because of the specific structural property and strong hydrophobicity, the obtained PMSQ microsphere dispersed well in the ethylene-vinyl acetate copolymer (EVA) matrix to form EVA/PMSQ hybrid. Subsequently, the thermal properties of both EVA and EVA/PMSQ hybrid were investigated through the TGA and DSC tests. The presence of PMSQ microsphere generates a significant delay in the thermal degradation processes of EVA, thus improving the thermal stability of EVA. The PMSQ microsphere also obviously increases the onset crystallization temperature and the crystallization rate of EVA, meaning that adding PMSQ microsphere enhances the crystallization ability of EVA. Finally, by applying rheological tests and microscopic observation, EVA/PMSQ hybrid was found to further improve the flow behavior of Qinghai waxy crude oil than the neat EVA did. The EVA/PMSQ hybrid can act as heterogeneous nucleation templates of wax crystals, and favor the formation of wax crystal flocs with increased size and compactness, thus inhibiting the continuous wax crystal network structure and further improving the flow behavior of the waxy crude oil.

Microstructural effects on effective piezoelectric responses of textured PMN-PT ceramics

The effective piezoelectric properties of [001]c fiber textured Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) ceramics were studied by phase-field modeling. The effects of microstructures such as texture, grain shape, grain boundaries, residual pores and heterogeneous growth templates were investigated. It was found that the degree of texture plays a dominant role in determining the properties. The pores, heterogeneous templates and grain boundaries reduce the properties significantly at high degrees of texture with the effect diminishing at decreasing degrees of texture. The presence of heterogeneous templates leads to a more significant reduction in the properties than pores although the piezoelectric coefficients of pores are zero. The shape of grains has a weak effect at all degrees of texture. By utilizing the experimentally measured microstructural parameters in the calculations and comparing the computed properties with the corresponding measurements, we showed that the low performance of sintered textured PMN-PT ceramics (d33∼1000 pC/N) relative to single crystals (d33∼2800 pC/N) is mainly due to the insufficiently high degree of texture even with Lotgering factors up to 0.9, while the influences of other microstructures are weak.

Template-Induced Nucleation of Isonicotinamide Polymorphs

By studying the potential of different heterogeneous templates to stimulate heterogeneous nucleation, this work aims to enhance the current knowledge of heterogeneous nucleation mechanisms and to obtain improved control of polymorphic selectivity in solution crystallization. The possibility of inducing nucleation of different isonicotinamide (INA) polymorphs by using heterogeneous templates, exhibiting porous and regular surfaces structures in the nanometer range, such as synthetic zeolite ZSM-5, mesoporous aluminosilicate MCM-41, and TiO2 in both rutile and anatase phase, was investigated by monitoring in real-time the course of the crystallization process. Experiments demonstrated that all used templates were effective in reducing induction time, thus being successful in enhancing the nucleation rate of INA. Furthermore, the ability of the TiO2 template in anatase form to induce the formation of a mixture of metastable forms I and III, thus diverting the expected course of polymorph crystallization due to INA self-association in ethanol, was demonstrated, providing an additional tool to achieve polymorphic selectivity in solution crystallization.

Efficient and robust multi-template tracking using multi-start interactive hybrid search

This paper presents an efficient, accurate, and robust template-based visual tracker. In this method, the target is represented by two heterogeneous and adaptive Gaussian-based templates which can model both short- and long-term changes in the target appearance. The proposed localization algorithm features an interactive multi-start optimization process that takes into account generic transformations using a combination of sampling- and gradient-based techniques in a unified probabilistic framework. Both the short- and long-term templates are used to find the best location of the target, simultaneously. This approach further increased both the efficiency and accuracy of the proposed tracker. The contributions of the proposed tracking method include: (1) Flexible multi-model target representation which in general can accurately and robustly handle challenging situations such as significant appearance and shape changes, (2) Robust template updating algorithm where a combination of tracking time step, a forgetting factor, and an uncertainty margin are used to update the mean and variance of the Gaussian functions, and (3) Efficient and interactive multi-start optimization which can improve the accuracy, robustness, and efficiency of the target localization by parallel searching in different time-varying templates. Several challenging and publicly available videos have been used to both demonstrate and quantify the superiority of the proposed tracking method in comparison with other state-of-the-art trackers.

RoadRunner for Heterogeneous Web Pages Using Extended MinHash

The Internet presents large amount of useful information which is usually formatted for its users, which makes it hard to extract relevant data from diverse sources. Therefore, there is a significant need of robust, flexible Information Extraction (IE) systems that transform the web pages into program friendly structures such as a relational database will become essential. IE produces structured data ready for post processing. Roadrunner will be used to extract information from template web pages. In this paper, we present novel algorithm for extracting templates from a large number of web documents which are generated from heterogeneous templates. The proposed system focuses on information extraction from heterogeneous web pages. We cluster the web documents based on the common template structures so that the template for each cluster is extracted simultaneously. The resultant clusters will be given as input to the Roadrunner system.

TEXT: Automatic Template Extraction from Heterogeneous Web Pages

World Wide Web is the most useful source of information. In order to achieve high productivity of publishing, the webpages in many websites are automatically populated by using the common templates with contents. The templates provide readers easy access to the contents guided by consistent structures. However, for machines, the templates are considered harmful since they degrade the accuracy and performance of web applications due to irrelevant terms in templates. Thus, template detection techniques have received a lot of attention recently to improve the performance of search engines, clustering, and classification of web documents. In this paper, we present novel algorithms for extracting templates from a large number of web documents which are generated from heterogeneous templates. We cluster the web documents based on the similarity of underlying template structures in the documents so that the template for each cluster is extracted simultaneously. We develop a novel goodness measure with its fast approximation for clustering and provide comprehensive analysis of our algorithm. Our experimental results with real-life data sets confirm the effectiveness and robustness of our algorithm compared to the state of the art for template detection algorithms.