scholarly journals Universal motion of mirror-symmetric microparticles in confined Stokes flow

2020 ◽  
Vol 117 (36) ◽  
pp. 21865-21872
Author(s):  
Rumen N. Georgiev ◽  
Sara O. Toscano ◽  
William E. Uspal ◽  
Bram Bet ◽  
Sela Samin ◽  
...  
Keyword(s):  
Particle Trajectory ◽  
Microfluidic Channel ◽  
Mirror Plane ◽  
Master Curves ◽  
Comprehensive Understanding ◽  
Exact Shape ◽  
Universal Motion ◽  
Stop Flow ◽  
Respective Characteristic ◽  
Particle Geometry

Comprehensive understanding of particle motion in microfluidic devices is essential to unlock additional technologies for shape-based separation and sorting of microparticles like microplastics, cells, and crystal polymorphs. Such particles interact hydrodynamically with confining surfaces, thus altering their trajectories. These hydrodynamic interactions are shape dependent and can be tuned to guide a particle along a specific path. We produce strongly confined particles with various shapes in a shallow microfluidic channel via stop flow lithography. Regardless of their exact shape, particles with a single mirror plane have identical modes of motion: in-plane rotation and cross-stream translation along a bell-shaped path. Each mode has a characteristic time, determined by particle geometry. Furthermore, each particle trajectory can be scaled by its respective characteristic times onto two master curves. We propose minimalistic relations linking these timescales to particle shape. Together these master curves yield a trajectory universal to particles with a single mirror plane.

scholarly journals Single-step synthesis of three-dimensional particles using non-uniform UV polymerization

2021 ◽  
Author(s):  
Navid Hakimi
Keyword(s):  
Uv Light ◽  
Three Dimensional ◽  
Microfluidic Channel ◽  
Precursor Solution ◽  
Monomer Conversion ◽  
Single Step ◽  
Shape Dependence ◽  
Straightforward Method ◽  
One Step ◽  
Stop Flow

Polymer-based microparticles are increasingly utilized in a range of biotechnology application. There is growing evidence that microparticle shape is an important parameter governing its functionality. Yet, there currently exists no straightforward method to controllably synthesize a large number of highly three-dimensional (3D) microparticles. In this thesis, we develop a one-step two-dimensional (2D) stop-flow lithography method that exploits the non-uniformity of the polymerizing ultraviolet (UV) light, UV adsorption by opaque nanoparticles in the precursor solution, and discontinuous photomask patterns, to make highly curved 3D microparticles. We investigate the microparticle shape dependence on each parameter by independently tuning the field and focus of the UV light, adding opaque magnetic nanoparticles to the precursor solution, and using a variety of photomask patterns.We also perform numerical simulations of oxygen concentration and monomer conversion in the microfluidic channel, to predict the particle shape. By simplifying the synthesis of high curvature 3D particles with 3D surface features and branched structures, our method may lead to the expanded use of microparticles in research and in industry.

scholarly journals Single-step synthesis of three-dimensional particles using non-uniform UV polymerization

2021 ◽  
Author(s):  
Navid Hakimi
Keyword(s):  
Uv Light ◽  
Three Dimensional ◽  
Microfluidic Channel ◽  
Precursor Solution ◽  
Monomer Conversion ◽  
Single Step ◽  
Shape Dependence ◽  
Straightforward Method ◽  
One Step ◽  
Stop Flow

Polymer-based microparticles are increasingly utilized in a range of biotechnology application. There is growing evidence that microparticle shape is an important parameter governing its functionality. Yet, there currently exists no straightforward method to controllably synthesize a large number of highly three-dimensional (3D) microparticles. In this thesis, we develop a one-step two-dimensional (2D) stop-flow lithography method that exploits the non-uniformity of the polymerizing ultraviolet (UV) light, UV adsorption by opaque nanoparticles in the precursor solution, and discontinuous photomask patterns, to make highly curved 3D microparticles. We investigate the microparticle shape dependence on each parameter by independently tuning the field and focus of the UV light, adding opaque magnetic nanoparticles to the precursor solution, and using a variety of photomask patterns.We also perform numerical simulations of oxygen concentration and monomer conversion in the microfluidic channel, to predict the particle shape. By simplifying the synthesis of high curvature 3D particles with 3D surface features and branched structures, our method may lead to the expanded use of microparticles in research and in industry.

The Changing Patterns of North Korea’s International Film Co-Productions Since the 1980s: A Global Value Chain Approach

2020 ◽  
pp. 83-108
Author(s):  
Moon Hwy-Chang ◽  
Wenyang Yin
Keyword(s):  
Value Chain ◽  
North Korea ◽  
Film Industry ◽  
International Standards ◽  
The Political ◽  
Global Value Chain ◽  
Comprehensive Understanding ◽  
Changing Patterns ◽  
Film Productions

Although North Korea is one of the most closed countries in the world, it has long been pursuing international cooperation with other countries in order to upgrade the quality of its film industry to international standards. Preceding studies on this topic have mainly focused on the political influences behind filmmaking in general and very few studies have exclusively dealt with North Korea’s international co-productions. In this respect, in order to develop a comprehensive understanding of the internalization strategy of North Korea’s film productions, this paper uses the global value chain as a framework for analysis. This approach helps understand the internationalization pattern of each value chain activity of film co-productions in terms of the film location and the methods for collaborating with foreign partners. By dividing the evolution of North Korea’s international co-productions into three periods since the 1980s, this paper finds that although North Korea has shown mixed results with different aspects of the film value chain, it has generally improved its internationalization over the three periods. This paper further provides strategic directions for North Korea by learning some of the successful Chinese experiences in the film sector regarding collaboration with foreign partners—to foster a win-win situation for all involved parties.

Taʾwīl and the Meaning of the Text in the Arabic Language: An Introduction to Understanding the Qur'an

2010 ◽  
Vol 12 (1-2) ◽  
pp. 337-314
Author(s):  
ʿAbd Allāh Muḥammad al-Shāmī
Keyword(s):  
Figurative Language ◽  
Arabic Language ◽  
Literary Text ◽  
Arabic Text ◽  
Comprehensive Understanding ◽  
Original Meaning ◽  
High Literature

The question of clarifying the meaning of a given Arabic text is a subtle one, especially as high literature texts can often be read in more than one way. Arabic is rich in figurative language and this can lead to variety in meaning, sometimes in ways that either adhere closely or diverge far from the ‘original’ meaning. In order to understand a fine literary text in Arabic, one must have a comprehensive understanding of the issue of taʾwīl, and the concept that multiplicity of meaning does not necessarily lead to contradiction. This article surveys the opinions of various literary critics and scholars of balāgha on this issue with a brief discussion of the concepts of tafsīr and sharḥ, which sometimes overlap with taʾwīl.

CLEARANCE AND STOP FLOW STUDIES IN GLUCAGON MEDIATED HYPERELECTROLYTURIA

1972 ◽  
Vol 68 (3_Suppl) ◽  
pp. S92 ◽  
Author(s):  
P. O. Schwille ◽  
B. Barth
Keyword(s):  
Stop Flow

POLIGAMI DALAM PERSPEKTIF AL-QUR’AN

2016 ◽  
Vol 1 (2) ◽  
pp. 35-50
Author(s):  
Makrum Makrum
Keyword(s):  
Qualitative Research ◽  
Islamic Law ◽  
Qualitative Approach ◽  
Comprehensive Understanding ◽  
Research Results ◽  
Library Research ◽  
Difference Of Opinion ◽  
Controversial Problem ◽  
The Difference ◽  
Interpretation Method

This paper is discusion the polygamy is still a controversial problem, although much discussed and examined. The difference of opinion among scholars make this problem continues to potentially raises the agree and disagree. Even though it has been regulated in Act Number 1 of 1974 concerning marriage and the compilation of Islamic law (KHI), this does not necessarily make the problem of polygamy is complete. Not a few perpetrators of polygamy choose married under the hand or by sirri. This research uses qualitative approach by implementing thematic interpretation method (maudhu'i) to obtain a comprehensive understanding about polygamy in the Qur'an. The Data obtained through the study of a library research by sharing the data that comes from the various verse of the Qur'an, hadith, book fiqh, research results, books and the news in various media outlets in order to complete the interpretation of the verses of polygamy. Based on the results of this research it is known that the verses of the Qur'an gives a very tight restrictions for those who want to in polygamy. Justice that the conditions of polygamy is not only were quantitative but also qualitative research. In the context of historical-socio, the command of polygamy is intended as a form of the solution to avoid injustice to orphans women. Even if polygamy still want to do, should the husband marrying the widows who have lighten the orphan.

Improved micro-impedance spectroscopy to determine cell barrier properties

2020 ◽  
Vol 4 (3) ◽  
pp. 150-155 ◽  
Author(s):  
Md. Mehadi Hasan Sohag ◽  
Olivier Nicoud ◽  
Racha Amine ◽  
Abir Khalil-Mgharbel ◽  
Jean-Pierre Alcaraz ◽  
...  
Keyword(s):  
Impedance Spectroscopy ◽  
Epithelial Cells ◽  
Lipid Bilayers ◽  
Cultured Cells ◽  
Cell Model ◽  
Measurement Techniques ◽  
Cell Monolayer ◽  
Microfluidic Channel ◽  
Small Surface ◽  
Resistance Pathway

AbstractThe goal of this study was to determine whether the Tethapod system, which was designed to determine the impedance properties of lipid bilayers, could be used for cell culture in order to utilise micro-impedance spectroscopy to examine further biological applications. To that purpose we have used normal epithelial cells from kidney (RPTEC) and a kidney cancer cell model (786-O). We demonstrate that the Tethapod system is compatible with the culture of 10,000 cells seeded to grow on a small area gold measurement electrode for several days without affecting the cell viability. Furthermore, the range of frequencies for EIS measurements were tuned to examine easily the characteristics of the cell monolayer. We demonstrate significant differences in the paracellular resistance pathway between normal and cancer kidney epithelial cells. Thus, we conclude that this device has advantages for the study of cultured cells that include (i) the configuration of measurement and reference electrodes across a microfluidic channel, and (ii) the small surface area of 6 parallel measurement electrodes (2.1 mm2) integrated in a microfluidic system. These characteristics might improve micro-impedance spectroscopy measurement techniques to provide a simple tool for further studies in the field of the patho-physiology of biological barriers.

APROXIMACIÓN A UNA CONCEPCIÓN TEÓRICO-METODOLÓGICA DE LOS PROCESOS DE PROFESIONALIZACIÓN PEDAGÓGICA EN LA EDUCACIÓN SUPERIOR.

2013 ◽  
Vol 1 (3) ◽  
Author(s):  
Olga Gloria Barbón Pérez ◽  
Julia Añorga Morales
Keyword(s):  
Higher Education ◽  
Key Words ◽  
Educación Superior ◽  
Comprehensive Understanding ◽  
Educacion Superior ◽  
Essential Step ◽  
Palabras Clave ◽  
Theoretical Conception ◽  
Design And Practice ◽  
Conscious Activity

El esclarecimiento de algunas de las concepciones que constituyen la base de los procesos de profesionalización pedagógica es un paso esencial para el éxito de los mismos. El presente artículo tiene como propósito aunar reflexiones que posibiliten un acercamiento hacia una concepción teórico-metodológica de los procesos de profesionalización pedagógica en la Educación Superior.El diseño y la puesta en práctica de los procesos de profesionalización pedagógica en la Educación Superior no pueden ser improvisados. Exigen, como actividad consciente, la consideración de determinados presupuestos teóricos y metodológicos que lo sustenten, y de su consideración como proceso pedagógico especial. Palabras clave: concepción teórica, concepción metodológica, profesionalización pedagógica.   ABSTRACT   Gaining on clarity concerning some of the conceptions that lie under the pedagogical professionalization processes is an essential step towards their own success. The article focuses on gathering insights that help get a more comprehensive understanding of a theoretic-methodological conception of the pedagogical professionalization processes in higher education. Both design and practice of these processes can not be improvised. They demand, as any other conscious activity, to take into account theoretical and methodological grounds and their consideration as a especial pedagogical process.   Key words: theoretical conception, methodological grounds, pedagogical professionalization.   Clarifying some of the concepts that form the basis of the processes of pedagogical professionalization is an essential step for their success.  This paper aims to join some reflections that enable the approaching to a theoretical-methodological conception of the processes of pedagogical professionalization in Higher Education.  Designing and implementing the processes of pedagogical professionalization cannot be improvised.  They demand, as a conscious activity, the consideration of certain supporting assumptions in theory and method, and their consideration as a special pedagogical process.   Keywords: theoretical conception, methodological conception, pedagogical professionalization. Recibido: Julio 2013 Aprobado: Agosto 2013

Sign in / Sign up

Export Citation Format

Share Document