Creation Of Patterns Research Articles

Study on Aqueous Humour Hydrodynamics of Glaucoma Condition Using 3D Printed Model and Particle Image Velocimetry (PIV)

This study aims to explore the knowledge on fluid flow properties of the aqueous humour (AH), specifically on the anterior segment (AS) of the human eye for a medical condition called Glaucoma. The research objectives are to study on fluid flow characteristics of velocity and pressure of the AH on the AS of the eye using enlarged 3D printed model and computational analysis, and also to analyse the suitability of the 3D generated anterior AS in fluid flow analysis application on particle image velocimetry (PIV). Using polyvinyl alcohol (PVA) as a water-soluble 3D printing filament, a 3D model of the AS of the human eye was generated with SolidWorks 2018 and printed using Creality Ender 3. This printed model serves as the pattern for silicon rubber mould production using vacuum casting process. Analysis of AH flow hydrodynamics are conducted with computational analysis using ANSYS Workbench 19.2. Key findings support that use of PVA material suite the creation of specific shapes and patterns for 3D modelling applications alike, and silicon rubber moulding creates a non-reactive and long-lasting mould for PIV applications. Computational analysis findings support the use of the generated model for PIV applications. Overall, the study successfully supports the use of 3D printed model for PIV application and future work that can be induced include direct experimentation of the mould with PIV.

Stretchable Conductors Fabricated by Stencil Lithography and Centrifugal Force-Assisted Patterning of Liquid Metal.

Embedding liquid metals (LMs) into an elastomer is emerging as a promising strategy for stretchable conductors. Existing manufacturing techniques are struggling between spatial resolution and process complexity and are limited to chemically resistant substrates. Here, we report on a hybrid process combining stencil lithography and centrifugal force-assisted patterning of liquid metal for the development of LM-based stretchable conductors. The selective wetting behavior of oxide-removed eutectic gallium–indium (EGaIn) on metal patterns defined by stencil lithography enables micrometer scale LM patterns on an elastomeric substrate. Stencil lithography allows for defining metal regions without harsh chemical treatments, making it suitable for a wide range of substrates. Microscale LM patterns are achieved by efficiently removing the excess material by the centrifugal forces experienced from spinning the substrate. The proposed approach allows for the creation of LM patterns with a line width as small as 2 μm on a stretchable poly(dimethylsiloxane) (PDMS) substrate. The electrical measurement results show that the fabricated EGaIn devices can endure 40% mechanical strain over several thousands of cycles. Furthermore, a stencil design using microbridges is proposed to address the mechanical stability issue in stencil lithography. An EGaIn conductor with a serpentine structure and an interdigitated capacitor are fabricated and characterized. The results demonstrate that the patterned serpentine conductors retain their functionality with applied mechanical strain up to 80%. The performance of the interdigitated capacitors upon applied strain is in good agreement with the theoretical estimation. Finally, we demonstrate our approach also on poly(octamethylene maleate (anhydride) citrate) (POMaC) substrates to broaden the use of the proposed method to not only flexible and stretchable but also biodegradable substrates, opening a way for in vivo transient microsystem engineering. The work presented here provides a versatile and reliable approach for manufacturing stretchable conductors.

Learning and teaching by literature. "Casus" of Polish romanticism created in country

This article is devoted to the issue of one of the methods of informal education in the Romantic period, namely literature. Polish modern national consciousness was formed during the partitions, and the place of its formation was the émigré literature. The ideas flowing from it penetrate into the literature created in the country, the latter being more involved in the creation and dissemination of national patterns in society. The issue of imitating in domestic literature the patterns developed by bards is also raised.

Vent distribution and sub-volcanic systems: Myths, fallacies, and some plausible facts

Characterization of spatially distributed volcanism includes analysis of vent alignments, zones of high probability density and cluster membership assignment. Attempts to identify patterns from the spatial distribution of vents have resorted to various methods with the underlying assumption that results from any of those methods should provide quantitative evidence concerning the structure of the array. In contrast, the physical conditions leading to the creation of specific patterns of distribution have received less attention. In this work, the basis for some of the common expectations of studies of vent distribution, and how those expectations match the individual method-inherent assumptions, are reviewed. Throughout this work it is shown that the spatial distribution of volcanic vents allows us to extract much information concerning the physical structure of the sub-volcanic system. Nevertheless, attention must be given to the fact that not all systems are equal, and therefore, that it is a myth that any quantitative method can provide reliable information. Furthermore, it is shown that some methods even might yield false clues leading to the statistical validation of structures that have no physical support. Thus, in this paper it is highlighted that the selection of methods that fulfill the physical constraints likely to exist on the case of interest is extremely important to promote identification of the most plausible configurations in a robust form. Failure to acknowledge the importance of method selection can be detrimental for the correct understanding of the physical mechanisms underlying volcanic activity, and therefore such practices need to be avoided.

Scheduling the Main Professional Football League of Argentina

In this paper, we describe our work in scheduling Argentina’s First Division professional football league, the Superliga. Following existing work in sports scheduling, we develop an integer programming model for the Superliga season schedule and then, solve it using a decomposition approach. Unlike previous work, this scheme is based on the creation and assignment of cluster patterns, which take advantage of the model’s geographically driven handling of sporting fairness. We also model the assignment of matches to specific dates and time slots while simultaneously considering various conditions relating to or imposed by game broadcasters, the government, and international tournament calendars. Our work was implemented to schedule the Superliga’s 2018–2019 and 2019–2020 seasons, achieving clear improvements on a number of criteria over the previous approach.

Enhanced species coexistence in Lotka-Volterra competition models due to nonlocal interactions

We introduce and analyze a spatial Lotka-Volterra competition model with local and nonlocal interactions. We study two alternative classes of nonlocal competition that differ in how each species’ characteristics determine the range of the nonlocal interactions. In both cases, nonlocal interactions can create spatial patterns of population densities in which highly populated clumps alternate with unpopulated regions. These non-populated regions provide spatial niches for a weaker competitor to establish in the community and persist in conditions in which local models predict competitive exclusion. Moreover, depending on the balance between local and nonlocal competition intensity, the clumps of the weaker competitor vary from M-like structures with higher densities of individuals accumulating at the edges of each clump to triangular structures with most individuals occupying their centers. These results suggest that long-range competition, through the creation of spatial patterns in population densities, might be a key driving force behind the rich diversity of species observed in natural ecological communities.

English

BACKGROUND Every child is prone to traumatic injuries, the impact of these injuries is directly related to the intensity, force and direction from which the trauma is inflicted. Trauma to the oral cavity is rather more common in children and adolescents as compared to the adult population. Since dental trauma is unanticipated, instantaneous and accidental, it often needs immediate and emergency management, depending on the severity of the injury. Thus, it is tremendously important to understand the patterns of incidence, prevalence, aetiology and risk factors associated with traumatic dental injuries. This article aims to review the epidemiology, incidence, prevalence, aetiology, risk factors and current trends of traumatic dental injuries in children and adolescents. The aetiologic factors vary among countries and within different age groups. The risk of sustaining traumatic dental injuries is generally dependent on several elements like age, circumstance, geography, behaviour and culture. Changing lifestyle especially related to urbanisation has led to amplification in the prevalence of dental trauma. The emergence of new trends in the modern society has led to creation of newer patterns and risk factors for the same. Traumatic dental injuries are linked to biological, social, financial and psychological factors. This article provides an overview on the epidemiology of traumatic dental injuries. This topic is of public health importance. This review is important to understand the underlying risk factors in order to reduce the prevalence and incidence of dental trauma. Educating the public regarding this will reduce the incidence of dental trauma. KEY WORDS Dental Trauma, Aetiology, Risk Factors, Epidemiology, Prevalence, Prevention, Paediatric Dentistry

Local Polarization Reversal by Ion Beam Irradiation in SBN Single Crystals Covered by Dielectric Layer.

Formation of the domain structure by ion beam irradiation was studied in thermally depolarized Ce-doped strontium barium niobate single crystals covered by a dielectric layer. Three types of irradiation regimes were used: dot exposure, stripe exposure, and line exposure. The dependences of the domain size and depth on the irradiated dose were measured. The circular shape of the isolated domains with partially switched broad domain boundary was obtained. Isotropic domain growth was attributed to the step generation at the wall by merging with the residual nanodomains that appeared after thermal depolarization. The obtained linear dose dependence of the switched area was attributed to the screening of the depolarization field by the injected charge. The shape distortion of the domains growing in the neighborhood with already created ones was attributed to the electrostatic interaction of the approaching charged domain walls. The obtained results can be applied for the creation of precise domain patterns with arbitrary orientation and shape to produce nonlinear optical devices with improved characteristics, including electrically tunable diffractive optical elements.

Transport and assembling microparticles via Marangoni flows in heating and cooling modes

The processes of the particles transfer in liquid media and the creation of structures of required configurations on substrates are of great importance in such areas as materials science, coatings, optoelectronics and biomedical researches. To control of the transfer of large ensembles of particles and dynamically transform of the particle aggregates the precise and flexible methods are strongly required. In this work, we propose a method for manipulation of microparticles in volatile liquid layers hundreds of microns thick that relies on the control of Marangoni flows by changing a sign of the temperature gradient in the liquid by the local action of the heat source and/or the heat sink. We have clearly demonstrated the applicability of the method to perform of wide range of manipulations with the particle ensembles: particles assembling in the circular patterns on a substrate when heating is applied, transfer of particles away from a heat sink when the substrate is cooled, and creation of ring-like patterns by changing the temperature gradient sign during particle assembling process. We have also studied the influence of the liquid layer thickness on the particle transfer and the size of the resulting pattern. It was found out that when heating the final pattern area on substrate decreases with the layer thickness, while the time of the pattern formation increases with the layer thickness. In the cooling mode, the final cleaned area decreases with the number of particles but the dependence on the layer thickness is ambiguous. The characteristic time decreases with an increase in the number of particles and slightly increases with the layer thickness. It was also revealed that the increase in the layer thickness makes it possible to create the multilayer dense circular assemblies of particles. The proposed method is simple for implementation, flexible and can be applied for manipulation with particles of any physicochemical properties and shapes. The method is applicable for controlling both a single microparticle and a large group of particles.

PEDAGOGICAL CONDITIONS OF FORMATION OF ENTREPRENEURIAL THINKING OF HIGHER EDUCATION SEEKERS

The relevance of the chosen research topic is due to the fact that modern social and economic environment requires specialists in the area of physical culture and sports to be ready for self-realization of professional potential in terms of market economy, which requires certain knowledge and skills to start and develop their own business. The purpose of the article is to suggest the pedagogical construction of forms and methods of teaching within the disciplines which ensure the formation of entrepreneurial thinking of future bachelors in physical culture and sports. To achieve this goal, abstract-logical and system-structural research methods have been used. The author’s concept of the process of formation of information and communication, economic and managerial components of entrepreneurial culture of future bachelors in physical culture and sports involves the implementation of preparatory, theoretical and practical stages. The formation of entrepreneurial culture at the preparatory stage is associated with the compulsory discipline “Information Technology in Physical Culture and Sports” (second semester). The theoretical stage involves mastering the study material of optional courses “Management in Physical Culture and Sports” (third semester), “Marketing of Physical Culture and Sports” (fourth semester), “Entrepreneurship in Physical Culture and Sports” (fifth semester), “Innovative technologies of sports training and physical culture” (sixth semester). The practical stage includes the preparation and defense of a course work and internships at enterprises that provide physical culture and health services. The disciplines ensuring the formation of entrepreneurship in higher education are defined as “Entrepreneurship in physical culture and sports” and the content module “Startups in the field” of the discipline “Innovative technologies of sports training and physical culture”. The discipline “Entrepreneurship in Physical Culture and Sports” has four credits, each of which corresponds to a certain module. The following forms and methods of organization of educational process have been offered: traditional lectures, lectures-press conferences, lectures-presentations, a round table, business games, method of problem-based learning, work in small groups and a method of individual work. These pedagogical conditions for the development of entrepreneurial thinking contribute to the creation and consolidation of certain patterns of successful business projects in the field, the acquisition of skills of self-analysis of entrepreneurial thinking using appropriate diagnostic techniques, create conditions for creative communication with the audience, collaboration in the creation process, emotional interaction and activate students’ independent cognitive activity, encourage them to perform search and research activities.

Ceramic Powder Bed Laser Sintering (CPBLS) on copper-doped hydroxyapatite: Creation of thin (5–50 μm thick) consolidated ceramic patterns

Implants made of ceramics, and more particularly of calcium phosphates (hydroxyapatite: HA, mainly), promoting intimate contact with natural bone are nowadays merging. Addition of copper ions in bio-ceramics is expected to increase the biological compatibilities of bone graft substitutes. Previous works have shown that copper-doped hydroxyapatite (Cu-doped HA) ceramics can be prepared by solid-state sintering between HA and CuO powder mixtures at about 1100 °C; but, copper-substituted HA was found to be metastable leading to apatitic grains and Cu-rich grain boundaries during the sintering process. Ultra-rapid sintering is so needed. Selective laser sintering (SLS) is an additive manufacturing process that possesses the advantage to be based on ultra-fast sintering process under laser irradiation. SLS being used in literature for the application of laser on polymer-ceramic or poymer-metal composites the proper term all along the paper is Ceramic Powder Bed Laser Sintering (CPBLS). To achieve densification of Cu-doped HA ceramics from CPBLS process, one should control the composition/morphology/structure of the powder bed as well as three other important CPBLS parameters: (i) the applied energy from the laser beam, (ii) the laser power and the laser scanning speed, (iii) the distance between two successive lased lines. In this paper, the impact of all the main CPBLS parameters controlling the sintering of dip-coated Cu-doped HA layers on glass substrates is carefully investigated. Possibility of the creation of thin consolidated Cu-doped HA ceramic patterns, using the ultra-fast CPBLS process, is finally shown.

On the Role of Transposable Elements in the Regulation of Gene Expression and Subgenomic Interactions in Crop Genomes

Transposable elements (TEs) represent a major and variable portion of plant genomes, and recent progress in genetics and genomics has highlighted the importance of different TE species as a useful genetic tool in crop breeding. TEs can cause changes in the pattern of gene expression, and regulate gene function by various means such as cis- up- or down-regulation of nearby genes through insertion at promoter, intron, exon and down-stream regions, and trans-production of short interfering RNAs (siRNAs) via two RNA-directed DNA methylation (RdDM) pathways. siRNAs generated through different RdDM pathways differ in length and have variable effects on TEs. For instance, noncoding siRNAs of 20–60 nt produced by RNA polymerase IV (dicer-independent) and 21/22 nt by Pol II (dicer-dependent) have only minor effects on TEs compared with 24 nt siRNAs produced by Pol IV (dicer-dependent pathways). Following whole-genome duplication (WGD) events after polyploidization in allopolyploids, TEs from either parent are able to induce siRNAs to regulate the complex polyploid genome. Those designated as ‘controllers’ usually reside in the dominant parent and affect the TEs of the recessive parent. Subgenome cross-talk thus appears to contribute to epigenetic regulation as well as reshuffling or restructuring of subgenomes and creation of novel patterns of genes expression/and variation in local or global copy number. In this review, we focus on recent progress in unraveling the role of TEs in gene expression regulation via TE-derived siRNAs in the context of polyploid plant evolution and environmental stress, and explore how ancient WGD and recent polyploidy affected the evolution of TE-induced epigenetic mechanisms.

Dimension of diffusion-limited aggregates grown on a line.

Diffusion-limited aggregation (DLA) has served for 40 years as a paradigmatic example for the creation of fractal growth patterns. In spite of thousands of references, no exact result for the fractal dimension D of DLA is known. In this Letter we announce an exact result for off-lattice DLA grown on a line embedded in the plane D=3/2. The result relies on representing DLA with iterated conformal maps, allowing one to prove self-affinity, a proper scaling limit, and a well-defined fractal dimension. Mathematical proofs of the main results are available in N. Berger, E. B. Procaccia, and A. Turner, Growth of stationary Hastings-Levitov, arXiv:2008.05792.

Advanced utilization of 3D digital image correlation for thermal and impact reliabilities of electronics components

PurposeThis paper aims to present an adaptation of digital image correlation (DIC) to the electronics industry for reliability assessment of electronic packages. Two case studies are presented: one for warpage measurement of a micro-electro-mechanical system (MEMS) package under different temperature conditions and the other for the measurement of transient displacements on the surface of a printed circuit board (PCB) assembly under free-fall drop conditions, which is for explaining the typical camera setup requirement and comparing among different boundary conditions by fastening methods of PCB.Design/methodology/approachDIC warpage measurements on a small device, such as a MEMS package, require a special speckle pattern. A new method for the creation of speckle patterns was developed using carbon coating and aluminum evaporative deposition. To measure the transient response on the surface of a PCB during a free-fall impact event, three-dimensional (3D) DIC was integrated with synchronized stereo-high speed cameras. This approach enables the measurement of full-field displacement on the PCB surface during a free-fall impact event, contrary to the localized information that is obtained by the conventional strain gage and accelerometer method.FindingsThe authors suggest the proposed patterning method to the small-sized microelectronics packages for DIC measurements. More generally, the idea is to have a thin layer of the dark or bright color of the background and then apply the white or black colored pattern, respectively, so that the surface has high contrast. Also, to achieve a proper size of speckles, this paper does not want to expose the measuring objects to high temperatures or pressures during the sample preparation stage. Of course, it seems a complicated process to use aluminum evaporator, carbon coater and electroformed mesh. However, the authors intend to share one of the solutions to achieve a proper pattern on such small-sized electronic packages.Originality/value3D DIC technique can be successfully implemented for the measurement of micro-scale deformations in small packages (such as MEMS) and for the analysis of dynamic deformation of complex PCB.

Russian Working Class Youth Media Representation: The Discourse Analysis Experience

The objective of this research is to investigate the recent discursive turn in working class representation in the Russian media. The means of creation and translation of normative class patterns, stereotypes and political agency within Russian media have been studied using the theoretical framework of critical discourse analysis. The empirical basis of the research is the textual transcripts of the key communicative events marking the working class as a political subject. The qualitative analysis allowed us to distinguish the rhetorical techniques and semiotic resources of working-class representation in the political field: thematic repertoire, format, practices which interlocutors use in addressing each other, language style and naming. It has been established that the forgotten concept of a “working class” was actualized and entrenched in the official political discourse in 2011. It was borrowed from left-wing political forces and re-assembled as one of the means of ruling class positioning in the 2011–2012 electoral cycle. Industrial working class representatives were included in public discourse as a part of the political staging, the consequences of which led to minor social changes. The populist discourse of working-class politicians as a “voice of common people” was constructed to oppose it to the protesting “creative class” threatening the main political force. The short-term political goal of power agents was to represent working-class people and youth especially as a political subject loyal to the existing regime, embedded into the current political system and ready to defend it if necessary. The nostalgic rhetorical technics were primarily used to re-launch “working class project”.
 Keywords: working class, working-class youth, discourse analysis, populism, political discourse

Ligand-Controlled Electrochromic Diversification with Multilayer Coated Metallosupramolecular Polymer Assemblies.

Designing surface-confined molecular systems capable of expressing changes in functional properties as a result of slight variations in chemical structure under the influence of an external stimulus is of contemporary interest. In this context, we have designed three tetraterpyridine ligands with variations in their core architecture (phenyl vs tetraphenylethynyl vs bithiophene) to create spray-coated electrochromic assemblies of iron(II)-based metallosupramolecular polymer network films on transparent conducting oxide substrates. These assemblies exhibited molecular permeability and spectroelectrochemical properties that are in turn dictated by the ligand structure. Electrochromic films with high coloration efficiencies (up to 1050 cm2/C) and superior optical contrast (up to 76%) with a concomitant color-to-color redox transition were readily achieved. These functional switching elements were integrated into sandwich-type electrochromic cells (CE up to 641 cm2/C) that exhibited high contrast ratios of up to 56%, with attractive ON-OFF ratios, fast switching kinetics, and high operational stability. Every measurable spectroelectrochemical property of the films and devices is an associated function of the ligand structure that coordinates the same metal ion to different extents. While exhibiting a ligand-structure induced differential metal coordination leading to porosity and spectroelectrochemical diversification, these assemblies allow the creation of electrochromic patterns and images by a simple spray-coating technique.

System of forming control signals by correction devices with creation of neural network patterns based on matrix analysis

The compensating devices are controlled in the structure of the automatic control system in conjunction with the sensors included in a particular node of the power grid. But the overall state of the local power grid for the reactive power flow is not considered. It is proposed to generate control signals to correction devices by processing the information obtained by monitoring from remote sensors of voltage and current of the distribution grid. It is possible to use the matrix method of forming the control signals to correction devices to adjust the grid parameters. To improve the energy efficiency of correction devices in the monitoring structure, it is proposed to use static reactive power compensators (SVCs) based on magneto-valve elements. The proposed distribution grid monitoring structure with the transfer of information over a local area network from sensors to correction devices makes it possible to stabilize the required grid parameters among consumers and minimize the loss of electrical energy from reactive power flow.

Additive Manufacturing of a Micropatterned Stamp for Transfer Printing of Quantum Dots

Transfer printing is a powerful technique for the quick and cost-effective creation of micro-structured patterns from various electronic materials. However, the production of the required stamps is often costly and time-consuming. In this study, we demonstrate how such a stamp can be custom designed and quickly made from a polyurethane-based resin by three-dimensional vat photopolymerization. A stamp featuring an array of 204 by 512 µm sized pixels was reproduced with a high dimensional accuracy of ±0.25% and successfully applied in transfer printing of a quantum dot (QD) material with electroluminescent properties. Due to the working principle of the printer used, both the stamp and the print image obtained had a characteristic yet homogeneous raster pattern. The insights gained will be useful in the additive manufacturing of tools for use in printing electronic devices.

Implemetation of a referential framework to evaluate the sustainable development of family farmers in the Southeast of Uruguay

This research aimed to explore means of evaluating a co-innovation and interinstitutional project for the sustainable development of family farmers in the Southeast of Uruguay (named FPTA 343) in order to finally implement an Evaluation Monitoring Framework (EMF) for assessing the accomplishment of the main actors’ aims. Data arose primarily from diagnoses of the social, technical and economic situation in the region, and interaction activities with farmers in the local groups, institutions and technicians (through interviews and workshops). Results demonstrated it is possible to adapt and implement an EMF, including the following steps: 1. Describing the region or formulating the problem, including values of the actors involved. 2. Discussing boundaries using multiple methodologies and theories (especially some that allow to explore sources of motivation, power, knowledge and legitimacy), and planning for rural sustainable development, considering the principles of “endogeneity”. Actors were able to actively participate by getting involved in the follow-up and evaluation of the project. The generation of shared spaces of dialogue is considered a starting point for the promotion of actions, contributing to farmers feeling subjects of the development to be encouraged, preventing identified issues of marginalisation and increasing their chances of sustainability. The most important contribution of this research is the creation of new ties, patterns and expectations, as well as the communication of new ways of appreciating extension, that could lead the generation of new purposes and goals.

Automatic Text Summarization Using Genetic Algorithm and Repetitive Patterns

Taking into account the increasing volume of text documents, automatic summarization is one of the important tools for quick and optimal utilization of such sources. Automatic summarization is a text compression process for producing a shorter document in order to quickly access the important goals and main features of the input document. In this study, a novel method is introduced for selective text summarization using the genetic algorithm and generation of repetitive patterns. One of the important features of the proposed summarization is to identify and extract the relationship between the main features of the input text and the creation of repetitive patterns in order to produce and optimize the vector of the main document features in the production of the summary document compared to other previous methods. In this study, attempts were made to encompass all the main parameters of the summary text including unambiguous summary with the highest precision, continuity and consistency. To investigate the efficiency of the proposed algorithm, the results of the study were evaluated with respect to the precision and recall criteria. The results of the study evaluation showed the optimization the dimensions of the features and generation of a sequence of summary document sentences having the most consistency with the main goals and features of the input document.