Relevant bibliographies by topics / DNA bubbles

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Book chapters
  4. Conference papers
  5. Reports

Academic literature on the topic 'DNA bubbles'

Author: Grafiati
Published: 4 June 2021
Last updated: 4 February 2022

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'DNA bubbles.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "DNA bubbles"

1

Makasheva, Kristina A., Anton V. Endutkin, and Dmitry O. Zharkov. "Requirements for DNA bubble structure for efficient cleavage by helix–two-turn–helix DNA glycosylases." Mutagenesis 35, no. 1 (2019): 119–28. http://dx.doi.org/10.1093/mutage/gez047.

Full text
Abstract:
Abstract Oxidative DNA lesions, constantly generated by both endogenous and environmentally induced reactive oxygen species, are removed via the base excision repair pathway. In bacteria, Fpg and Nei DNA glycosylases, belonging to the helix–two-turn–helix (H2TH) structural superfamily, remove oxidised purines and pyrimidines, respectively. Interestingly, the human H2TH family glycosylases, NEIL1, NEIL2 and NEIL3, have been reported to prefer oxidative lesions in DNA bubbles or single-stranded DNA. It had been hypothesised that NEIL2 might be involved in the repair of lesions in transcription bubbles; however, bubble-like structures may appear in other cellular contexts such as displacement loops (D-loops) associated with transcription, recombination or telomere maintenance. The activities of bacterial Fpg and Nei on bubble substrates were not addressed. Also, it is not known whether H2TH enzymes process bubbles containing the third DNA or RNA strand, and how the bubble length and position of the lesion within a bubble affect the excision. We have investigated the removal of 8-oxoguanine (8-oxoG) and 5,6-dihydrouracil (DHU) by Escherichia coli Fpg and Nei and human NEIL1 and NEIL2 from single-strand oligonucleotides, perfect duplexes, bubbles with different numbers of unpaired bases (6–30), bubbles containing the lesion in different positions and D-loops with the third strand made of DNA or RNA. Fpg, NEIL1 and NEIL2 efficiently excised lesions located within bubbles, with NEIL1 and NEIL2 being specific for DHU, and Fpg removing both 8-oxoG and DHU. Nei, in contrast, was significantly active only on DHU located in double-stranded DNA. Fpg and NEIL1 also tolerated the presence of the third strand of either DNA or RNA in D-loops if the lesion was in the single-stranded part, and Fpg, Nei and NEIL1 excised lesions from the double-stranded DNA part of D-loops. The presence of an additional unpaired 5′-tail of DNA or RNA did not affect the activity. No significant position preference for lesions in a 12-mer bubble was found. Overall, the activities of Fpg, NEIL1 and NEIL2 on these non-canonical substrates are consistent with the possibility that these enzymes may participate in the repair in structures arising during transcription or homologous recombination.
APA, Harvard, Vancouver, ISO, and other styles
2

Severin, N., W. Zhuang, C. Ecker, A. A. Kalachev, I. M. Sokolov, and J. P. Rabe. "Blowing DNA Bubbles." Nano Letters 6, no. 11 (2006): 2561–66. http://dx.doi.org/10.1021/nl061989b.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Gonzalez, Rodrigo, Yan Zeng, Vassili Ivanov, and Giovanni Zocchi. "Bubbles in DNA melting." Journal of Physics: Condensed Matter 21, no. 3 (2008): 034102. http://dx.doi.org/10.1088/0953-8984/21/3/034102.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Grinevich, A. A., A. A. Ryasik, and L. V. Yakushevich. "Trajectories of DNA bubbles." Chaos, Solitons & Fractals 75 (June 2015): 62–75. http://dx.doi.org/10.1016/j.chaos.2015.02.009.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Hariadi, Rizal F., Erik Winfree, and Bernard Yurke. "Determining hydrodynamic forces in bursting bubbles using DNA nanotube mechanics." Proceedings of the National Academy of Sciences 112, no. 45 (2015): E6086—E6095. http://dx.doi.org/10.1073/pnas.1424673112.

Full text
Abstract:
Quantifying the mechanical forces produced by fluid flows within the ocean is critical to understanding the ocean’s environmental phenomena. Such forces may have been instrumental in the origin of life by driving a primitive form of self-replication through fragmentation. Among the intense sources of hydrodynamic shear encountered in the ocean are breaking waves and the bursting bubbles produced by such waves. On a microscopic scale, one expects the surface-tension–driven flows produced during bubble rupture to exhibit particularly high velocity gradients due to the small size scales and masses involved. However, little work has examined the strength of shear flow rates in commonly encountered ocean conditions. By using DNA nanotubes as a novel fluid flow sensor, we investigate the elongational rates generated in bursting films within aqueous bubble foams using both laboratory buffer and ocean water. To characterize the elongational rate distribution associated with a bursting bubble, we introduce the concept of a fragmentation volume and measure its form as a function of elongational flow rate. We find that substantial volumes experience surprisingly large flow rates: during the bursting of a bubble having an air volume of 10 mm3, elongational rates at least as large as ϵ˙=1.0×108 s−1 are generated in a fragmentation volume of ∼2×10−6μL. The determination of the elongational strain rate distribution is essential for assessing how effectively fluid motion within bursting bubbles at the ocean surface can shear microscopic particles and microorganisms, and could have driven the self-replication of a protobiont.
APA, Harvard, Vancouver, ISO, and other styles
6

Wu, Weimin, Naiqian Cheng, Lindsay Black, Hendrik Dietz, and Alasdair Steven. "Biphasic Packing of DNA and Internal Proteins in Bacteriophage T4 Heads Revealed by Bubblegram Imaging." Viruses 12, no. 11 (2020): 1282. http://dx.doi.org/10.3390/v12111282.

Full text
Abstract:
The virions of tailed bacteriophages and the evolutionarily related herpesviruses contain, in addition to highly condensed DNA, substantial quantities of internal proteins. These proteins (“ejection proteins”) have roles in scaffolding, maturational proteolysis, and cell-to-cell delivery. Whereas capsids are amenable to analysis at high resolution by cryo-electron microscopy, internal proteins have proved difficult to localize. In this study, we investigated the distribution of internal proteins in T4 by bubblegram imaging. Prior work has shown that at suitably high electron doses, radiation damage generates bubbles of hydrogen gas in nucleoprotein specimens. Using DNA origami as a test specimen, we show that DNA does not bubble under these conditions; it follows that bubbles represent markers for proteins. The interior of the prolate T4 head, ~1000 Å long by ~750 Å wide, has a bubble-free zone that is ~100–110 Å thick, underlying the capsid shell from which proteins are excluded by highly ordered DNA. Inside this zone, which is plausibly occupied by ~4 layers of coaxial spool, bubbles are generated at random locations in a disordered ensemble of internal proteins and the remainder of the genome.
APA, Harvard, Vancouver, ISO, and other styles
7

Zeng, Yan, and Giovanni Zocchi. "Mismatches and Bubbles in DNA." Biophysical Journal 90, no. 12 (2006): 4522–29. http://dx.doi.org/10.1529/biophysj.105.069591.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

van Erp, T. S., S. Cuesta-López, and M. Peyrard. "Bubbles and denaturation in DNA." European Physical Journal E 20, no. 4 (2006): 421–34. http://dx.doi.org/10.1140/epje/i2006-10032-2.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Hennig, D., J. F. R. Archilla, and J. M. Romero. "Modelling the thermal evolution of enzyme-created bubbles in DNA." Journal of The Royal Society Interface 2, no. 2 (2005): 89–95. http://dx.doi.org/10.1098/rsif.2004.0024.

Full text
Abstract:
The formation of bubbles in nucleic acids (NAs) is fundamental in many biological processes such as DNA replication, recombination, telomere formation and nucleotide excision repair, as well as RNA transcription and splicing. These processes are carried out by assembled complexes with enzymes that separate selected regions of NAs. Within the frame of a nonlinear dynamics approach, we model the structure of the DNA duplex by a nonlinear network of coupled oscillators. We show that, in fact, from certain local structural distortions, there originate oscillating localized patterns, that is, radial and torsional breathers, which are associated with localized H-bond deformations, reminiscent of the replication bubble. We further study the temperature dependence of these oscillating bubbles. To this aim, the underlying nonlinear oscillator network of the DNA duplex is brought into contact with a heat bath using the Nosé–Hoover method. Special attention is paid to the stability of the oscillating bubbles under the imposed thermal perturbations. It is demonstrated that the radial and torsional breathers sustain the impact of thermal perturbations even at temperatures as high as room temperature. Generally, for non-zero temperature, the H-bond breathers move coherently along the double chain, whereas at T =0 standing radial and torsional breathers result.
APA, Harvard, Vancouver, ISO, and other styles
10

Liang, C., and S. A. Gerbi. "Analysis of an origin of DNA amplification in Sciara coprophila by a novel three-dimensional gel method." Molecular and Cellular Biology 14, no. 2 (1994): 1520–29. http://dx.doi.org/10.1128/mcb.14.2.1520.

Full text
Abstract:
The replication origin region for DNA amplification in Sciara coprophila DNA puff II/9A was analyzed with a novel three-dimensional (3D) gel method. Our 3D gel method involves running a neutral/neutral 2D gel and then cutting out vertical gel slices from the area containing replication intermediates, rotating these slices 90 degrees to form the third dimension, and running an alkaline gel for each of the slices. Therefore, replication intermediates are separated into forks and bubbles and then are resolved into parental and nascent strands. We used this technique to determine the size of forks and bubbles and to confirm the location of the major initiation region previously mapped by 2D gels to a 1-kb region. Furthermore, our 3D gel analyses suggest that only one initiation event in the origin region occurs on a single DNA molecule and that the fork arc in the composite fork-plus-bubble pattern in neutral/neutral 2D gels does not result from broken bubbles.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "DNA bubbles"

1

Zeng, Yan. "Bubbles and mismatches in DNA melting." Diss., Restricted to subscribing institutions, 2007. http://proquest.umi.com/pqdweb?did=1324387071&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Deng, Peigang. "Micro bubble actuator for DNA hybridization enhancement /." View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?MECH%202004%20DENG.

Full text
Abstract:
Thesis (Ph. D.)--Hong Kong University of Science and Technology, 2004.<br>Includes bibliographical references (leaves 156-165). Also available in electronic version. Access restricted to campus users.
APA, Harvard, Vancouver, ISO, and other styles
3

Wijngaart, Wouter van der. "Designing Microfluidic Control Components." Doctoral thesis, KTH, Signals, Sensors and Systems, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3352.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Kaiser, Vojtěch. "Stochastická dynamika bublin v DNA." Master's thesis, 2011. http://www.nusl.cz/ntk/nusl-313899.

Full text
Abstract:
Název práce: Stochastická dynamika bublin v DNA Autor: Bc. Vojtěch Kaiser Katedra: Katedra fyziky kondenzovaných látek Vedoucí diplomové práce: RNDr. Tomáš Novotný, Ph.D., Katedra fyziky kondenzovaných látek Abstrakt: Bubliny v DNA jsou místa, kde se vlivem tepelných či torsních vlivů otevírá dvojšroubovice DNA. Tyto bubliny jsou považovány za důležité pro termodynamiku DNA [56] a biologické procesy s DNA spojené [23,40,43,49]. V článcích [38, 39] byla řešena stochastická dynamika bublin v DNA na zá- kladě Polandova-Scheragova modelu a získány analytické výsledky při tep- lotě denaturace DNA a pro asymptotiku dlouhých časů, zvláště pro hustotu pravděpodobnosti času setkání konců bubliny. V této práci navazujeme na tyto výsledky a počítáme celkový tvar této hustoty pravděpodobností s vy- užitím numerické inverse analytických vztahů v Laplacově obraze. Dále po- čítáme hustotu pravděpodobnosti místa setkání konců bubliny. Odpovídající výsledky jsou numericky spočteny v případě molekul DNA konečné délky. Zachycování bubliny v oblastech bohatých na AT páry je modelováno jako subdifusivní systém dle článku [42] a jsou počítány stejné veličiny jako pro difusivní model. V závěru diskutujeme tyto výsledky a možnost jejich experi- mentálního ověření. Klíčová slova: bubliny v DNA,...
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "DNA bubbles"

1

Bensimon, David, Vincent Croquette, Jean-François Allemand, Xavier Michalet, and Terence Strick. "Manipulating DNA." In Single-Molecule Studies of Nucleic Acids and Their Proteins. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198530923.003.0002.

Full text
Abstract:
This chapter describes the various methods used to manipulate single DNA molecules and the considerations in the choice of one particular method. It starts with a description of DNA end-labelling, necessary to anchor the molecule to surfaces or beads that can be manipulated. A particular application of DNA anchoring is molecular combing, whereby the molecule is stretched on a surface by a receding meniscus. DNA rearrangements and replication bubbles can then be observed by fluorescence on these straightened molecules. It then looks at the forces at the molecular scale, which range from the smallest one due to thermal agitation, to the largest associated with breaking a covalent bond, via entropic and non-covalent bonding forces. It describes the tools used to manipulate single molecules (micro-needles, AFM cantilevers, optical, magnetic, and acoustic tweezers and traps, etc.), comparing their performances in terms of bandwidth and signal to noise (i.e., force and extension resolutions).
APA, Harvard, Vancouver, ISO, and other styles
2

deHaseth, Pieter L., and Laura Tsujikawa. "Probing the Role of Region 2 of Escherichia coli σ70 in Nucleation and Maintenance of the Single-Stranded DNA Bubble in RNA Polymerase-Promoter Open Complexes." In Methods in Enzymology. Elsevier, 2003. http://dx.doi.org/10.1016/s0076-6879(03)70047-0.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "DNA bubbles"

1

Campa, A. "Traveling bubbles in a model of DNA." In Modeling complex systems. AIP, 2001. http://dx.doi.org/10.1063/1.1386846.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Wu, Junqing, Gaurav Soni, Dazhi Wang, and Carl D. Meinhart. "AC Electrokinetic Pumps for Micro/NanoFluidics." In ASME 2004 International Mechanical Engineering Congress and Exposition. ASMEDC, 2004. http://dx.doi.org/10.1115/imece2004-61836.

Full text
Abstract:
We have developed micropumps for microfluidics that use AC electric fields to drive aqueous fluid motion through micro channels. These pumps operate at relatively low voltages (~5–10Vrms), and high frequencies (~100kHz). They have several distinct advantages over the DC electrokinetic pumps. The low voltages make the pumps well suited for a wide variety of biosensor and “Lab-on-a-Chip” applications (e.g. PCR chip for DNA amplification). The high frequencies minimize electrolysis, so that bubbles do not form on the electrode surfaces, and do not contaminate the working fluid. The pumps can also be used as active valves or precision micro-dispensers.
APA, Harvard, Vancouver, ISO, and other styles
3

Fang, Jun, and Igor A. Bolotnov. "Bubble Tracking Simulations of Turbulent Two-Phase Flows." In ASME 2016 Fluids Engineering Division Summer Meeting collocated with the ASME 2016 Heat Transfer Summer Conference and the ASME 2016 14th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/fedsm2016-1005.

Full text
Abstract:
Bubbly flow is quite common in various natural and engineering phenomena. In particular, nuclear engineers are interested in fundamental understanding of the bubbly flow behavior due to its importance in cooling light water reactor cores. Given the extreme conditions and complex support structures in nuclear reactor cores, it is very challenging to study the flow behavior using high-fidelity experiments. Typically validated computational codes are chosen as practical tools for the thermal-hydraulic and safety analyses. As the new generations of nuclear reactors are being developed, more advanced modeling techniques are required to design safe and efficient systems. Different from most simulation approaches, direct numerical simulation (DNS) employs no turbulence closure assumptions, which makes it a promising tool for model development. The major bottleneck of DNS was and remains to be the high computational cost, increasing exponentially with the Reynolds number. However, thanks to the on-going improvements in computer power, these computationally expensive simulations are becoming more and more affordable. Coupled with level-set interface tracking method (ITM), DNS can be used for the high-fidelity studies of two-phase bubbly flows with unprecedented details. Meanwhile, another concern that arises is how one can best take advantage of the ‘big data’ generated from large-scale DNS and translate it into new knowledge. The traditional level-set method utilizes a signed distance field to distinguish different phases while the interface is modeled by the zero level-set. Although level-set method can distinguish gas bubbles from the liquid phase, it cannot recognize and track individual bubbles which hinders the collection of useful bubble information. As a result, the bubble tracking capability has to be developed to improve the data extraction efficiency. In the present work, a marker field is created and advected for bubble distinction and extraction of detailed bubble parameters from the simulations. Each bubble in the flow gets assigned a unique ID, based on which the code will collect the corresponding bubble information. It has been demonstrated that bubble tracking capability can significantly improve the data extraction efficiency for level-set based two-phase flow simulations. Statistical analysis tools are also developed to post-process the recorded information about the bubbles to study the dependencies/correlations of bubble behavior with bubble local conditions. For example, in the pressurized water reactor (PWR) subchannel geometry investigated in this paper, bubbles are observed to experience different relative velocity when presenting at different distance from fuel rod surfaces. With proper grouping criterion, statistical analysis would allow introducing variable drag coefficient for bubbles based on their positions. These new insights are contributing to more accurate modeling of the multiphase computational fluid dynamic (M-CFD) simulations, and better prediction of two-phase flow behavior in engineering systems. Together with the analysis tools, bubble tracking capability will open a new door to study and understand two-phase flows.
APA, Harvard, Vancouver, ISO, and other styles
4

Tryggvason, G., J. Lu, and S. Biswas. "Direct Numerical Simulations of Bubbles in Vertical Channels." In ASME 2006 2nd Joint U.S.-European Fluids Engineering Summer Meeting Collocated With the 14th International Conference on Nuclear Engineering. ASMEDC, 2006. http://dx.doi.org/10.1115/fedsm2006-98102.

Full text
Abstract:
Recent DNS studies of bubbly flows in channels are discussed. Simulations of nearly spherical bubbly flows in vertical channels show that the bubbles move towards the wall for upflow and away from the wall for downflow in such a way that the core is in hydrostatic equilibrium. For down flow the wall layer is free of bubbles but for upflow there is an excess of bubbles in the wall layer. The liquid velocity in the core is uniform. For laminar downflow the velocity in the wall layer can be computed analytically but for upflow the velocity is strongly influenced by the presence of the bubbles. Results for turbulent flow show similar behavior and for downflow the velocity is given (almost) by the law of the wall. Several simulations are used to examine the effect of void fraction and bubble size for turbulent downflow.
APA, Harvard, Vancouver, ISO, and other styles
5

Cambareri, Joseph J., and Igor A. Bolotnov. "Interface Tracking Simulations of Two-Phase Flow Utilizing Adaptive Meshing Capabilities." In 2018 26th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/icone26-81247.

Full text
Abstract:
Due to the increase of computing efficiency and power, full-resolution two-phase flow simulations have become a practical research tool for model development and analysis of reactor flows. The expansion of state-of-the-art high performance computing (HPC) facilities allows for the use of direct numerical simulation (DNS) coupled with Interface Tracking Methods (ITM) to perform full resolution simulations. Given adequate spatial and temporal resolution, DNS can resolve all relevant turbulent scales, allowing for the extraction of high quality and detailed turbulent and two-phase flow numerical data for use in model development. While larger scale bubbly flow DNS are becoming ever more affordable, it is still computationally expensive due to the requirements of the spatial discretization. This presents the largest obstacle for future applications of DNS. For this reason, mesh adaptation techniques are sought after to reduce the computational expense of bubbly flow simulations in complex geometries. By fully resolving only the areas of specific interest, the computational costs of DNS can be reduced. Grid refinement can be based on the location of the interface between the two phases, area of greatest turbulent intensity, averaged bulk fluid velocity data, or the prediction of bubble movement. Coupled with an advanced bubble tracking algorithm, the path of individual bubbles moving through the computational domain can be predicted, and the computational mesh refined within the path area. This refinement can create tracks of greater resolution for the bubbles to move through in the domain, while keeping the bulk resolution of the mesh coarser. Through these means, the overall cost of the simulation is reduced, while high quality numerical data is still obtainable. This work outlines the enhancement of existing mesh adaptation algorithms to implement the bubble tracking refinement, and its practical applications to full resolution two-phase flow simulations.
APA, Harvard, Vancouver, ISO, and other styles
6

Dietzel, Dirk, Timon Hitz, Claus-Dieter Munz, and Andreas Kronenburg. "Expansion rates of bubble clusters in superheated liquids." In ILASS2017 - 28th European Conference on Liquid Atomization and Spray Systems. Universitat Politècnica València, 2017. http://dx.doi.org/10.4995/ilass2017.2017.4714.

Full text
Abstract:
The present work analyses the growth of multiple bubbles in superheated liquid jets by means of direct numericalsimulations (DNS). A discontinuous Galerkin approach is used to solve the Euler equations and an adequate in- terface resolution is ensured by applying finite-volume sub-cells in cells with interfaces. An approximate Riemann solver has been adapted to account for evaporation and provides consistency of all conserved quantities across the interface. The setup mimics conditions typical for orbital manoeuvring systems when liquid oxygen (LOX) is injected into the combustion chamber prior to ignition. The liquid oxygen will then be in a superheated state, bubble nucleation will occur and the growth of the bubbles will determine the break-up of the liquid jet. The expansion rates of bubble groups under such conditions are not known and standard models rely on single bubble assumptions. This is a first DNS study on bubble-bubble interactions in flash boiling sprays and on the effects of these interactions on the growth rates of the individual bubbles. The present simulations resolve a small section of the jet close to the nozzle exit and the growth of bubble groups inside of the jet is analysed. The results suggest that an individual bubble within the group grows more slowly than conventional models for single bubble growth would predict. The reduction in bubble growth can amount to up to 30% and depends on the distances between the bubbles and the number of bubbles within the bubble group. In the present case, the volume expansion of the superheated liquiddecreases by approximately 50% if the distance between the bubbles is doubled.DOI: http://dx.doi.org/10.4995/ILASS2017.2017.4714
APA, Harvard, Vancouver, ISO, and other styles
7

Zhang, Zheng, Kana Suzuki, Shigeo Hosokawa, and Akio Tomiyama. "Motion of Small Bubbles Near a Grid Spacer in a Two by Three Rod Bundle." In 16th International Conference on Nuclear Engineering. ASMEDC, 2008. http://dx.doi.org/10.1115/icone16-48468.

Full text
Abstract:
Several experiments have reported that departure from nucleate boiling (DNB) in a pressurized water reactor (PWR) fuel assembly often takes place just upstream of a grid spacer. Since DNB inception is to be tightly related with an extremely high void fraction in the vicinity of a heated wall, it is speculated that one of the causes of DNB inception is lateral migration of bubbles toward a fuel rod due to a flow induced by the grid spacer. Therefore, experiments are conducted to investigate the motion of small bubbles and liquid velocity profiles just upstream of a grid spacer in a two by three rod bundle. Tap water and air are used for the liquid and gas phases, respectively. The bulk liquid velocity ranges from 1.0 to 4.0 m/s and experiments are conducted at atmospheric pressure and room temperature. Trajectories of single small bubbles are recorded using a high-speed video camera. Mean liquid velocities and turbulence distributions upstream of the spacer are calculated based on 10,000 instantaneous velocity distributions measured by Particle Image Velocimetry (PIV). Discussion on the effects of the gird spacer on bubble motion is made based on the difference between the measured bubble trajectories and liquid streamlines. Numerical simulations using a three-dimensional two-way bubble tracking method are also carried out. The calculated trajectories of single bubbles and liquid velocity distributions are compared with the measured data. The main conclusions obtained are as follows: (1) just upstream of the grid spacer, bubbles are apt to migrate toward the rods and accumulate in the vicinity of the rod surface, (2) a centrifugal force caused by a curved streamline just upstream of the grid spacer is the main cause of lateral migration of bubbles toward the rods, and (3) the two-way bubble tracking method gives good predictions for trajectories of small bubbles upstream of the grid spacer and for liquid velocity profiles.
APA, Harvard, Vancouver, ISO, and other styles
8

Yi-Kuen Lee and Peigang Deng. "Bubble actuator enhanced DNA micro biosensor." In 2005 IEEE International Conference on Robotics and Biomimetics - ROBIO. IEEE, 2005. http://dx.doi.org/10.1109/robio.2005.246363.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Bois, G., and A. du Cluzeau. "DNS of Turbulent Bubbly Flows in Plane Channels Using the Front-Tracking Algorithm of TrioCFD." In ASME 2017 Fluids Engineering Division Summer Meeting. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/fedsm2017-69128.

Full text
Abstract:
Two-phase turbulence is studied using DNS of upward turbulent bubbly flows in a plane channel. Fully deformable monodispersed bubbles are tracked by the Front-Tracking algorithm implemented in TrioCFD code on the TRUST platform. Two sets of fluid properties are used. Firstly, two simulations are performed with virtual fluids at a low void fraction of 3% and for a Reynolds friction number of 127 to benchmark our code against [1]. Good agreements are obtained for both deformable and spherical cases. A third simulation closer to pressurized water reactor (PWR) conditions was performed at higher void fraction and Reynolds number to push the limits of DNS capabilities. DNS results are averaged (i) to provide reference profiles for an up-scaling methodology towards RANS two-fluid models and (ii) to analyze the equilibrium between buoyancy, surface tension, viscous and turbulent shear at statistically steady-state. Surface tension forces and turbulence are essentials to capture the equilibrium. Their accurate modeling is the key to velocities and void fraction predictions in averaged codes. Our analysis reveals the important role of surface tension, not only in the determination of the bubble shapes, but also as a source of local imbalance of the momentum transfer between phases. More advanced models considering interfacial energy are necessary to predict these flows.
APA, Harvard, Vancouver, ISO, and other styles
10

Simens, Mark P., and Javier Jime´nez. "Alternatives to Kelvin-Helmholtz Instabilities to Control Separation Bubbles." In ASME Turbo Expo 2006: Power for Land, Sea, and Air. ASMEDC, 2006. http://dx.doi.org/10.1115/gt2006-90670.

Full text
Abstract:
We study the control of two-dimensional laminar separation bubbles on a flat plate at low Reynolds numbers, using two-dimensional DNS. A range of steady separation bubbles is obtained varying the pressure gradient. They are forced by a zero-mass flow, oscillatory wall blowing with different perturbation amplitudes and frequencies. The reduction in bubble length as a function of frequency has two minima for sufficient high amplitudes. One of them is related to the Kelvin-Helmholtz instability of the separated boundary layer, while the other, most effective one, is here denoted as the low-frequency regime. In this regime large vortices are created which are not a consequence of an instability of the original bubble. On the contrary the forcing creates an unsteady separation bubble which evolves into a large vortex. These vortices have large radii and attach to the wall due to their self-induced pressure field while convecting across the adverse pressure gradient zone. Scaling relations for the effect of the forcing are proposed and tested.
APA, Harvard, Vancouver, ISO, and other styles

Reports on the topic "DNA bubbles"

1

Hillebrand, M., G. Kalosakas, Alan Bishop, and Ch Skokos. Bubble lifetimes in DNA gene promoters and their mutations affecting transcription. Office of Scientific and Technical Information (OSTI), 2021. http://dx.doi.org/10.2172/1798109.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Tryggvason, Gretar, Igor Bolotnov, Jun Fang, and Jiacai Lu. Verification of bubble tracking method and DNS examinations of single- and two-phase turbulent channel flows. Office of Scientific and Technical Information (OSTI), 2017. http://dx.doi.org/10.2172/1409272.

Full text
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'DNA bubbles' for particular source types:
Journal articles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography