Relevant bibliographies by topics / Chimera method

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  2. Dissertations / Theses
  3. Books
  4. Book chapters
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Academic literature on the topic 'Chimera method'

Author: Grafiati
Published: 4 June 2021
Last updated: 1 March 2025

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Journal articles on the topic "Chimera method"

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Polejaeva, Irina, and Shoukhrat Mitalipov. "Stem cell potency and the ability to contribute to chimeric organisms." REPRODUCTION 145, no. 3 (March 2013): R81—R88. http://dx.doi.org/10.1530/rep-12-0396.

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Mouse embryonic chimeras are a well-established tool for studying cell lineage commitment and pluripotency. Experimental chimeras were successfully produced by combining two or more preimplantation embryos or by introducing into host embryo cultured pluripotent embryonic stem cells (ESCs). Chimera production using genetically modified ESCs became the method of choice for the generation of knockout or knockin mice. Although the derivation of ESCs or ESC-like cells has been reported for other species, only mouse and rat pluripotent stem cells have been shown to contribute to germline-competent chimeras, which is the defining feature of ESCs. Herein, we describe different approaches employed for the generation of embryonic chimeras, define chimera-competent cell types, and describe cases of spontaneous chimerism in humans. We also review the current state of derivation of pluripotent stem cells in several species and discuss outcomes of various chimera studies when such cells are used.
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Brezzi, Franco, Jacques-Louis Lions, and Olivier Pironneau. "Analysis of a Chimera method." Comptes Rendus de l'Académie des Sciences - Series I - Mathematics 332, no. 7 (April 2001): 655–60. http://dx.doi.org/10.1016/s0764-4442(01)01904-8.

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Czech, M. P., A. Chawla, C. W. Woon, J. Buxton, M. Armoni, W. Tang, M. Joly, and S. Corvera. "Exofacial epitope-tagged glucose transporter chimeras reveal COOH-terminal sequences governing cellular localization." Journal of Cell Biology 123, no. 1 (October 1, 1993): 127–35. http://dx.doi.org/10.1083/jcb.123.1.127.

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The insulin-regulated adipocyte/skeletal muscle glucose transporter (GLUT4) displays a characteristic steady-state intracellular localization under basal conditions, whereas the erythrocyte/brain transporter isoform (GLUT1) distributes mostly to the cell surface. To identify possible structural elements in these transporter proteins that determine their cellular localization, GLUT1/GLUT4 chimera cDNA constructs that contain the hemagglutinin epitope YPYDVPDYA (HA) in their major exofacial loops were engineered. Binding of monoclonal anti-HA antibody to non-permeabilized COS-7 cells expressing HA-tagged transporter chimeras revealed that expression of transporters on the cell surface was strongly influenced by their cytoplasmic COOH-terminal domain. This method also revealed a less marked, but significant effect on cellular localization of amino acid residues between transporter exofacial and middle loops. The subcellular distribution of expressed chimeras was confirmed by immunofluorescence microscopy of permeabilized COS-7 cells. Thus, HA-tagged native GLUT4 was concentrated in the perinuclear region, whereas a chimera containing the COOH-terminal 29 residues of GLUT1 substituted onto GLUT4 distributed to the plasma membrane, as did native GLUT1. Furthermore, a chimera composed of GLUT1 with a GLUT4 COOH-terminal 30-residue substitution exhibited a predominantly intracellular localization. Similar data was obtained in CHO cells stably expressing these chimeras. Taken together, these results define the unique COOH-terminal cytoplasmic sequences of the GLUT1 and GLUT4 glucose transporters as important determinants of cellular localization in COS-7 and CHO cells.
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Goglidze, V. B. "NOT THE DE M'YUZANE CHIMERAS OF PSYCHOANALYSIS." ГИПНОЗ И ПСИХОАНАЛИЗ В КЛИНИЧЕСКОЙ И ЭКСПЕРИМЕНТАЛЬНОЙ ПСИХОЛОГИИ 1, no. 3 (September 25, 2024): 5–16. http://dx.doi.org/10.47475/3034-3291-2024-1-3-4-14.

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Relevance. In the article, the author expresses his opinion about the unconscious creative Chimera of Michel de M'uzan. The relevance of this is in reducing the spread of hoaxes in psychoanalysis. Intention. The author's intention is to provide evidence that every possible encounter with a creative Chimera is a consequence of the psychodynamic processes of the therapist-patient dyad. Methodology. Analysis of specialized literature and clinical cases. The results and their analysis. As a result of the study, a conclusion was made about the rational origin of the newly appeared images of Chimeras. The author also calls for the interpretative retelling of the patient's mental material to be considered chimeras. The results and their analysis. The analyst provides his own Unconscious, Ego and Superego to support the still unstable mental instances of the analyzed. Awareness of the therapist's own mental processes helps to expand knowledge about himself and helps to avoid hoaxes and deviations from the method of psychoanalysis.
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Mysara, Mohamed, Yvan Saeys, Natalie Leys, Jeroen Raes, and Pieter Monsieurs. "CATCh, an Ensemble Classifier for Chimera Detection in 16S rRNA Sequencing Studies." Applied and Environmental Microbiology 81, no. 5 (December 19, 2014): 1573–84. http://dx.doi.org/10.1128/aem.02896-14.

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ABSTRACTIn ecological studies, microbial diversity is nowadays mostly assessed via the detection of phylogenetic marker genes, such as 16S rRNA. However, PCR amplification of these marker genes produces a significant amount of artificial sequences, often referred to as chimeras. Different algorithms have been developed to remove these chimeras, but efforts to combine different methodologies are limited. Therefore, two machine learning classifiers (reference-based andde novoCATCh) were developed by integrating the output of existing chimera detection tools into a new, more powerful method. When comparing our classifiers with existing tools in either the reference-based orde novomode, a higher performance of our ensemble method was observed on a wide range of sequencing data, including simulated, 454 pyrosequencing, and Illumina MiSeq data sets. Since our algorithm combines the advantages of different individual chimera detection tools, our approach produces more robust results when challenged with chimeric sequences having a low parent divergence, short length of the chimeric range, and various numbers of parents. Additionally, it could be shown that integrating CATCh in the preprocessing pipeline has a beneficial effect on the quality of the clustering in operational taxonomic units.
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Patidar, Manoj, Naveen Yadav, and Sarat K. Dalai. "Influence of Length and Amino Acid Composition on Dimer Formation of Immunoglobulin based Chimera." Current Pharmaceutical Design 24, no. 11 (June 27, 2018): 1211–23. http://dx.doi.org/10.2174/1381612823666171018115206.

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Background: The dimeric immunoglobulin (Ig) chimeras used for drug targeting and delivery are preferred biologics over their monomeric forms. Designing these Ig chimeras involves critical selection of a suitable Ig base that ensures dimer formation. In the present study, we systematically analyzed several factors that influence the formation of dimeric chimera. We designed and predicted 608 cytokine-Ig chimeras where we tested the contributions of (1) different domains of Ig constant heavy chain, (2) length of partner proteins, (3) amino acid (AA) composition and (4) position of cysteine in the formation of homodimer. Method: The sequences of various Ig and cytokines were procured from Uniprot database, fused and submitted to COTH (CO-THreader) server for the prediction of dimer formation. Contributions of different domains of Ig constant heavy chain, length of chimeric proteins, AA composition and position of cysteine to the homodimer formation of 608 cytokine-Ig chimeras were tested. Various in silico approaches were adopted for validating the in silico findings. Experimentally we also validated our approach by expressing the chimeric design of shorter cytokine with Ig domain in CHO cells and analyzing the protein by SDS-PAGE. Results: Our results advocate that while the CH1 region and the Hinge region of Ig heavy chain are critical, the length of partner proteins also crucially influences homodimer formation of the Ig-based chimera. We also report that the CH1 domain of Ig is not required for dimer formation of Ig based chimera in the presence of larger partner proteins. For shorter partner proteins fused to CH2-CH3, careful selection of partner sequence is critical, particularly the hydrophobic AA composition, cysteine content & their positions, disulphide bond formation property, and the linker sequences. We validated our in silico observation by various bioinformatics tools and checked the ability of chimeras to bind with the receptors of native protein by docking studies. As a proof of concept, we have expressed the chimeric proteins in CHO cells and found that our design favors the synthesis of dimeric proteins. Conclusion: Our structural prediction study suggests that extra amino acids in the range of 15-20 added to the CH2 domain of Ig is a critical requirement to make homodimer. This information from our study will have implication in designing efficacious homodimeric chimera.
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Johnson, J. G. "Method of Multiple Working Hypotheses: A chimera." Geology 18, no. 1 (1990): 44. http://dx.doi.org/10.1130/0091-7613(1990)018<0044:momwha>2.3.co;2.

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Wright, Erik S., L. Safak Yilmaz, and Daniel R. Noguera. "DECIPHER, a Search-Based Approach to Chimera Identification for 16S rRNA Sequences." Applied and Environmental Microbiology 78, no. 3 (November 18, 2011): 717–25. http://dx.doi.org/10.1128/aem.06516-11.

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ABSTRACTDECIPHER is a new method for finding 16S rRNA chimeric sequences by the use of a search-based approach. The method is based upon detecting short fragments that are uncommon in the phylogenetic group where a query sequence is classified but frequently found in another phylogenetic group. The algorithm was calibrated for full sequences (fs_DECIPHER) and short sequences (ss_DECIPHER) and benchmarked against WigeoN (Pintail), ChimeraSlayer, and Uchime using artificially generated chimeras. Overall, ss_DECIPHER and Uchime provided the highest chimera detection for sequences 100 to 600 nucleotides long (79% and 81%, respectively), but Uchime's performance deteriorated for longer sequences, while ss_DECIPHER maintained a high detection rate (89%). Both methods had low false-positive rates (1.3% and 1.6%). The more conservative fs_DECIPHER, benchmarked only for sequences longer than 600 nucleotides, had an overall detection rate lower than that of ss_DECIPHER (75%) but higher than those of the other programs. In addition, fs_DECIPHER had the lowest false-positive rate among all the benchmarked programs (<0.20%). DECIPHER was outperformed only by ChimeraSlayer and Uchime when chimeras were formed from closely related parents (less than 10% divergence). Given the differences in the programs, it was possible to detect over 89% of all chimeras with just the combination of ss_DECIPHER and Uchime. Using fs_DECIPHER, we detected between 1% and 2% additional chimeras in the RDP, SILVA, and Greengenes databases from which chimeras had already been removed with Pintail or Bellerophon. DECIPHER was implemented in the R programming language and is directly accessible through a webpage or by downloading the program as an R package (http://DECIPHER.cee.wisc.edu).
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Kozhemyachenko, A. A., and A. V. Favorskaya. "Grid Convergence Analysis of Grid-Characteristic Method on Chimera Meshes in Ultrasonic Nondestructive Testing of Railroad Rail." Журнал вычислительной математики и математической физики 63, no. 10 (October 1, 2023): 1687–705. http://dx.doi.org/10.31857/s0044466923100071.

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A three-dimensional direct problem of ultrasonic nondestructive testing of a railroad rail treated as a linear elastic medium is solved by applying a grid-characteristic method on curved structured Chimera and Cartesian background meshes. The algorithm involves mutual interpolation between Chimera and Cartesian meshes that takes into account the features of the transition from curved to Cartesian meshes in three-dimensional space. An analytical algorithm for generating Chimera meshes is proposed. The convergence of the developed numerical algorithms under mesh refinement in space is analyzed. A comparative analysis of the full-wave fields of the velocity modulus representing the propagation of a perturbation from its source is presented.
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Hu, Xiaodong, Zhonghua Lu, Jian Zhang, Xiazhen Liu, Wu Yuan, Shan Liang, and Haikuo Zhang. "A parallel algorithm for chimera grid with implicit hole cutting method." International Journal of High Performance Computing Applications 34, no. 2 (April 25, 2019): 169–77. http://dx.doi.org/10.1177/1094342019845042.

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The chimera grid methods have been widely used in the simulation of flow over complex configurations and unsteady moving boundary process. Lee and Baeder presented the implicit hole cutting (IHC) method, which improves the practicability and robustness of chimera grid method. But the excessive time consumption of this method restricts the scalability of parallelism. In this article, based on the parallel implementation of IHC method with structured multi-block grid, the factors which restrict the performance and efficiency are analyzed. Cartesian auxiliary grid is introduced to reduce the communication and computing cost. Finally, test cases are presented to demonstrate the effectiveness of this algorithm, and the calculation and data communication are reduced on the premise of maintaining accuracy.
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Dissertations / Theses on the topic "Chimera method"

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Galbraith, Marshall C. "A Discontinuous Galerkin Chimera Overset Solver." University of Cincinnati / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1384427339.

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Stern, Louis G. "An explicitly conservative method for time-accurate solution of hyperbolic partial differential equations on embedded Chimera grids /." Thesis, Connect to this title online; UW restricted, 1996. http://hdl.handle.net/1773/6758.

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Demir, H. Ozgur. "Computational Fluid Dynamics Analysis Of Store Separation." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605294/index.pdf.

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In this thesis, store separation from two different configurations are solved using computational methods. Two different commercially available CFD codes
CFD-FASTRAN, an implicit Euler solver, and an unsteady panel method solver USAERO, coupled with integral boundary layer solution procedure are used for the present computations. The computational trajectory results are validated against the available experimental data of a generic wing-pylon-store configuration at Mach 0.95. Major trends of the separation are captured. Same configuration is used for the comparison of unsteady panel method with Euler solution at Mach 0.3 and 0.6. Major trends are similar to each other while some differences in lateral and longitudinal displacements are observed. Trajectories of a fueltank separated from an F-16 fighter aircraft wing and full aircraft configurations are found at Mach 0.3 using only the unsteady panel code. The results indicate that the effect of fuselage is to decrease the drag and to increase the side forces acting on the separating fueltank from the aircraft. It is also observed that the yawing and rolling directions of the separating fueltank are reversed when it is separated from the full aircraft configuration when compared to the separation from the wing alone configuration.
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Dorange, Alexis. "Développement d'une méthodologie pour la simulation haute fidélité de l'aérodynamique des micro-drones." Electronic Thesis or Diss., Institut polytechnique de Paris, 2024. http://www.theses.fr/2024IPPAX103.

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L'objectif cette thèse est le développement d'une méthodologie permettant la simulation haute fidélité de tous types de géométries de micro-drones.Bien que ces véhicules soient très présents dans l'espace aérien, la physique des écoulements qu'ils induisent est encore mal connue, en outre ils sont associés à des problématiques de nuisance acoustique.L'écoulement autour de ces derniers présente des phénomènes complexes de mécanique des fluides tels que la transition laminaire-turbulent, la séparation ou encore un bulbe de décollement laminaire.La Simulation des Grandes Échelles (Large Eddy Simulation - LES) est mise en œuvre dans cette étude car elle permet de prendre en compte avec précision les phénomènes complexes mis en jeu dans la couche limite des hélices de drone, au contraire des approches de plus basses fidélités.Une autre problématique liée aux drones est leur géométrie complexe, qui peut grandement compliquer l'étape de génération de maillage en vue de leur simulation. Dans cette optique, les méthodes Chimère et de frontières immergées sont utilisées pour simplifier cette étape. La première permet de mailler indépendamment et plus simplement chacune des pales à l'aide de maillages structurées curvilignes, tandis que la seconde permet de s'affranchir de la génération d'un maillage conforme autour du fuselage. Un couplage entre ces deux méthodes est finalement développé pour la simulation d'éléments géométriques très proches les uns des autres.Tout d'abord, les résultats d'une simulation LES sont présentés pour un rotor dont la géométrie des pales est entièrement définie analytiquement. Cette simulation permet de mettre en évidence la présence d'un bulbe de séparation laminaire ainsi que des mécanismes de rattachements et de décollements laminaires et turbulents. Elle met également en évidence les différentes sources de bruit générées par les hélices.Par la suite, une étude sur la montée en complexité géométrique permet de mesurer l'effet de l'ajout des différentes parties du drone sur les performances du rotor. En particulier, ces simulations mettent en avant l'impact du moyeu et des bras sur les efforts aérodynamiques, ainsi que les émissions acoustiques globales.Au terme de cette thèse, un drone complet est finalement simulé à l'aide de l'ensemble des éléments méthodologiques introduits dans le cadre de ces travaux. Les efforts globaux ainsi que l'acoustique complète du drone sont analysés. Cette application représente la première simulation connue d'un drone complet réalisée à l'aide d'une approche LES
The objective of this thesis is to develop a methodology for the high-fidelity simulation of all types of micro-unmanned aerial vehicle geometry.Despite their prevalence in the airspace, the flow physics they induce remain poorly understood and present acoustic nuisance issues.The flow around these vehicles presents a range of complex fluid mechanics phenomena, including the laminar-turbulent transition, separation, and the formation of a laminar separation bubble.The Large Eddy Simulation (LES) approach is employed in this study to accurately account for the complex phenomena occurring within the boundary layer of drone propellers, which cannot be adequately captured by lower fidelity methods.A further issue associated with UAVs is their complex geometry, which can significantly complicate the mesh generation process for their simulation.In consideration of the aforementioned considerations, the Chimera and immerged boundary methods are employed to simplify this stage. The former facilitates the meshing by using curvilinear structured meshes for each blade independently, while the latter eliminates the need to generate a conformal mesh around the fuselage. A coupling between these two methods is finally developed for the simulation of geometric elements that are in close proximity to one another.In the first instance, the results of an LES simulation are presented for a rotor whose blade geometry is entirely defined analytically. The simulation demonstrates the presence of a laminar separation bubble as well as laminar and turbulent attachment and detachment mechanisms. Furthermore, the simulation highlights the various sources of noise generated by the propellers.Subsequently, an investigation into of increasing geometric complexity on rotor performance was conducted by incorporating different components into the UAV. In particular, these simulations demonstrate the influence of the hub and arms on aerodynamic forces and overall acoustics emissions.At the conclusion of this thesis, a complete UAV is finally simulated using all the methodological elements introduced as part of this work. The overall forces and the complete acoustics of the UAV are analysed. This application represents the first known simulation of a complete UAV using an LES approach
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Taylor, Mary. "In vitro methods for the construction of chimeras in potato." Thesis, University of Bath, 1988. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383696.

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Montroni, Elisa <1986&gt. "New Methods in Organocatalysis." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6336/1/Montroni_Elisa_tesi.pdf.

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In the following chapters new methods in organocatalysis are described. The design of new catalysts is explored starting from the synthesis and the study of ion tagged prolines to their applications and recycle, then moving to the synthesis of new bicyclic diarylprolinol silyl ethers and their use in organocatalytic transformations. The study of new organocatalytic reaction is also investigated, in particular bifunctional thioureas are employed to catalyse the conjugate addition of nitro compounds to 3-yilidene oxindoles in sequential and domino reactions. Finally, preliminary results on photochemical organocatalytic atom transfer radical addition to alkenes are discussed in the last chapter.
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Montroni, Elisa <1986&gt. "New Methods in Organocatalysis." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6336/.

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In the following chapters new methods in organocatalysis are described. The design of new catalysts is explored starting from the synthesis and the study of ion tagged prolines to their applications and recycle, then moving to the synthesis of new bicyclic diarylprolinol silyl ethers and their use in organocatalytic transformations. The study of new organocatalytic reaction is also investigated, in particular bifunctional thioureas are employed to catalyse the conjugate addition of nitro compounds to 3-yilidene oxindoles in sequential and domino reactions. Finally, preliminary results on photochemical organocatalytic atom transfer radical addition to alkenes are discussed in the last chapter.
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Moro, Lorenzo <1985&gt. "Complex chemical dynamics through engineering-like methods." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6202/1/TesiDoc_Moro.pdf.

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Most of the problems in modern structural design can be described with a set of equation; solutions of these mathematical models can lead the engineer and designer to get info during the design stage. The same holds true for physical-chemistry; this branch of chemistry uses mathematics and physics in order to explain real chemical phenomena. In this work two extremely different chemical processes will be studied; the dynamic of an artificial molecular motor and the generation and propagation of the nervous signals between excitable cells and tissues like neurons and axons. These two processes, in spite of their chemical and physical differences, can be both described successfully by partial differential equations, that are, respectively the Fokker-Planck equation and the Hodgkin and Huxley model. With the aid of an advanced engineering software these two processes have been modeled and simulated in order to extract a lot of physical informations about them and to predict a lot of properties that can be, in future, extremely useful during the design stage of both molecular motors and devices which rely their actions on the nervous communications between active fibres.
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Moro, Lorenzo <1985&gt. "Complex chemical dynamics through engineering-like methods." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6202/.

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Most of the problems in modern structural design can be described with a set of equation; solutions of these mathematical models can lead the engineer and designer to get info during the design stage. The same holds true for physical-chemistry; this branch of chemistry uses mathematics and physics in order to explain real chemical phenomena. In this work two extremely different chemical processes will be studied; the dynamic of an artificial molecular motor and the generation and propagation of the nervous signals between excitable cells and tissues like neurons and axons. These two processes, in spite of their chemical and physical differences, can be both described successfully by partial differential equations, that are, respectively the Fokker-Planck equation and the Hodgkin and Huxley model. With the aid of an advanced engineering software these two processes have been modeled and simulated in order to extract a lot of physical informations about them and to predict a lot of properties that can be, in future, extremely useful during the design stage of both molecular motors and devices which rely their actions on the nervous communications between active fibres.
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ODDONE, IRENE. "Vacuum Induced Nucleation as a method for freeze drying optimization." Doctoral thesis, Politecnico di Torino, 2016. http://hdl.handle.net/11583/2640463.

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Freeze drying is used to improve long-term stability of labile drugs. It comprises three different stages: freezing, primary drying, and secondary drying. Due to low values of pressure and temperature required in these stages, freeze drying is a cost-intensive process. Various authors have recently shown that the manipulation of the temperature of nucleation can provide benefits in terms of process optimization, and various technologies have been proposed to this purpose, such as electrofreezing, ultrasound, depressurization method, and ice fog. However, due to various problems of these technologies, such as the requirement of additional equipment and difficulties in scale-up, in this study the vacuum induced nucleation method was taken into consideration for its ease of application. Unfortunately, this method, as proposed in literature, produces defects in the cake structure because of blow-up of the frozen product and flake formation on the product surface, which are detrimental for the elegance of the final product and rejected by the pharmaceutical industry. For these reasons, a refined control technique has been here investigated and validated, showing that an accurate control of vacuum conditions can give a drastic reduction in cycle time along with an elegant product. The vacuum induced nucleation method consists in reducing the pressure within the drying chamber for a short time during the freezing stage. This pressure reduction produces the partial evaporation of water, which causes a reduction in product temperature and promotes the nucleation of ice. In this work I have developed a new method, still based on pressure reduction, that solved some of the problems of the original technique. In particular, once the desired value of pressure (which is product dependent) was reached, the drying chamber was isolated from the condenser for about 1 min. Because of that isolation, the pressure inside the drying chamber increased because of vapor accumulation, thus avoiding any esthetic defects to the product. A detailed investigation about the impact of the settings of the new control method on product and process performances was performed. To this purpose, various solutions containing mannitol, sucrose, lactose, dextran, glycine, polyvinylpyrrolidone, trehalose, and cellobiose were used. The results obtained showed that the method led to a high quality of the final product. Furthermore, showed that the induction of nucleation at higher temperature promoted the formation of very large crystals (see Fig. 1) with a consequent drastic reduction in cycle duration (due to lower values of product resistance to vapor flow, Rp). In order to promote the industrial scale-up of the method, a monitoring system based on thin-film technology, that allows, besides the monitoring of the product temperature, the detection of the end of the nucleation event was developed. Once the method was developed, a detailed investigation on its impact on both product (i.e., structure and homogeneity) and process (i.e., primary and secondary drying time) was carried out. The impact of the method on within-batch (inter-vial) and within-vial (intra-vial) variability was investigated. Comparing the onset-offset of pressure ratio curves of various cycles, it was found that the use of controlled nucleation (instead of conventional shelf-ramped freezing) dramatically increased the inter-vial homogeneity (by about 50%). This result was also confirmed by comparing the residual moisture values at the end of drying, which showed lower variance for controlled nucleation with respect to uncontrolled. A study, focused on mannitol-based formulations, showed that both nucleation temperature and filling volume had an impact on pore size and its distribution along the lyophilized cake. This within-vial variability was quantified by analyzing the average pore dimension along the cake (by Image-J program). The homogeneity of the product was also studied in terms of polymorph formation. To this regard, X-ray diffraction and off-line Raman were used to identify the mannitol polymorphs present within the product, which was found to vary with the freezing protocol and the temperature of secondary drying. Off-line Raman spectroscopy was also used to evaluate the polymorph distribution along the cake, showing that the spectra collected at the top of each sample often contained slightly higher amounts of α and δ mannitol in comparison with the spectra recorded in the other regions of the same cake. Finally, the Raman tool was also used for the in-line monitoring of the product characteristics, increasing the knowledge related to polymorph formation during freeze drying. To this purpose, it was found that the hydrate form of mannitol (which can damage the product if released during product storage) was formed during the entire cycle (freezing and drying stages), but was transformed into anhydrous polymorph immediately after the vacuum within the chamber was released at the end of the cycle. The primary drying stage of the cycles was performed using in-line monitoring (DPE+ algorithm) and control (LyoDriver) to further optimize the freeze-drying cycle. The use of these tools showed that, to obtain the optimum freeze-drying cycle, it was necessary to work on both freezing and primary drying stages. The mass-transfer resistance values obtained from each cycle (by DPE+ algorithm estimation) were used to calculate the design space and simulate the process. The cycle simulation highlighted the reduction of the cycle duration using the control method proposed (in comparison with an uncontrolled stochastic cycles) and the influence of its operating conditions on freeze-drying cycle optimization. It was, finally, shown that the primary drying duration could be decreased up to about 55% in the case of controlled nucleation. A study focused on the moisture content of the product during secondary drying showed that the controlled nucleation led to higher values of residual moisture content in comparison with conventional freezing. This comparison was done for different secondary drying temperatures. The estimated kinetic constant of desorption was always higher in the case of uncontrolled cycles with respect to that for the controlled cycles, thus resulting in an increase of time needed for desorption when controlled nucleation was used. This was an expected result as control of nucleation leads to higher porosity and, thus, to a lower specific surface area available for the desorption of residual moisture. Although higher values of residual moisture content led to an additional time needed in the case of controlled nucleation to complete secondary drying stage, it was found that the total time to carry out the entire cycle was still smaller in the case of controlled nucleation in comparison with uncontrolled, thus confirming the advantage in using this control technique. Finally, the design space built for the secondary drying stage gave additional information about the impact of some operating conditions of the process on secondary drying time, thus giving a great contribution in the optimization of this step. The difference in water content between conventional and controlled freezing protocol was also investigated by in-line NIR spectroscopy analysis. This technology was able to discriminate between bound and surface water in freeze dried products. Differences in bound and surface water were detected only in the case of different temperature during secondary drying independently from the freezing protocol used.
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Books on the topic "Chimera method"

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S, Liou M., and Lewis Research Center. Institute for Computational Mechanics in Propulsion., eds. On the application of chimera/unstructured hybrid grids for conjugate heat transfer. Cleveland, Ohio: NASA Lewis Research Center, ICOMP, 1995.

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Meng-Sing, Liou, and Lewis Research Center. Institute for Computational Mechanics in Propulsion., eds. On the application of chimera/unstructured hybrid grids for conjugate heat transfer. Cleveland, Ohio: NASA Lewis Research Center, ICOMP, 1995.

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Angeles, Alejandro De Los, and Insoo Hyun. Chimera Research: Methods and Protocols. Springer New York, 2020.

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Angeles, Alejandro De Los, and Insoo Hyun. Chimera Research: Methods and Protocols. Springer New York, 2019.

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Li, Hui, and Justin Elfman. Chimeric RNA: Methods and Protocols. Springer, 2020.

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Li, Hui, and Justin Elfman. Chimeric RNA: Methods and Protocols. Springer, 2019.

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Snowdon, Jasper Whitfield. Standard Methods in the art of Change Ringing. Franklin Classics, 2018.

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Snowdon, Jasper Whitfield. Standard Methods in the Art of Change Ringing. Creative Media Partners, LLC, 2018.

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Joyner, Alexandra, ed. Gene Targeting. Oxford University Press, 1999. http://dx.doi.org/10.1093/oso/9780199637928.001.0001.

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Since the publication of the first edition of Gene Targeting: A Practical Approach in 1993 there have been many advances in gene targeting and this new edition has been thoroughly updated and rewritten to include all the major new techniques. It provides not only tried-and-tested practical protocols but detailed guidance on their use and applications. As with the previous edition Gene Targeting: A Practical Approach 2e concentrates on gene targeting in mouse ES cells, but the techniques described can be easily adapted to applications in tissue culture including those for human cells. The first chapter covers the design of gene targeting vectors for mammalian cells and describes how to distinguish random integrations from homologous recombination. It is followed by a chapter on extending conventional gene targeting manipulations by using site-specific recombination using the Cre-loxP and Flp-FRT systems to produce 'clean' germline mutations and conditionally (in)activating genes. Chapter 3 describes methods for introducing DNA into ES cells for homologous recombination, selection and screening procedures for identifying and recovering targeted cell clones, and a simple method for establishing new ES cell lines. Chapter 4 discusses the pros and cons or aggregation versus blastocyst injection to create chimeras, focusing on the technical aspects of generating aggregation chimeras and then describes some of the uses of chimeras. The next topic covered is gene trap strategies; the structure, components, design, and modification of GT vectors, the various types of GT screens, and the molecular analysis of GT integrations. The final chapter explains the use of classical genetics in gene targeting and phenotype interpretation to create mutations and elucidate gene functions. Gene Targeting: A Practical Approach 2e will therefore be of great value to all researchers studying gene function.
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(Editor), Melvin I. Simon, Jeremy Thorner (Editor), Scott D. Emr (Editor), and John N. Abelson (Editor), eds. Applications of Chimeric Genes and Hybrid Proteins, Part A: Gene Expression and Protein Purification (Methods in Enzymology, Volume 326) (Methods in Enzymology). Academic Press, 2000.

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Book chapters on the topic "Chimera method"

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Brezzi, F., J. L. Lions, and O. Pironneau. "The Chimera method for a model problem." In Numerical Mathematics and Advanced Applications, 817–25. Milano: Springer Milan, 2003. http://dx.doi.org/10.1007/978-88-470-2089-4_74.

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Eguzkitza, B., G. Houzeaux, R. Aubry, and O. Peredo. "An Implicit and Parallel Chimera Type Domain Decomposition Method." In Lecture Notes in Computational Science and Engineering, 577–84. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-35275-1_68.

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Jankowicz-Cieslak, Joanna, Florian Goessnitzer, Bradley J. Till, and Ivan L. Ingelbrecht. "Induced Mutagenesis and In Vitro Mutant Population Development in Musa spp." In Efficient Screening Techniques to Identify Mutants with TR4 Resistance in Banana, 3–20. Berlin, Heidelberg: Springer Berlin Heidelberg, 2022. http://dx.doi.org/10.1007/978-3-662-64915-2_1.

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AbstractMutagenesis of in vitro propagated bananas is an efficient method to introduce novel alleles and broaden genetic diversity. Mutations can be induced by treatment of plant cells with chemical mutagens or ionizing radiation. The FAO/IAEA Plant Breeding and Genetics Laboratory established efficient methods for mutation induction of in vitro shoot tips in banana using physical and chemical mutagens as well as methods for the efficient discovery of EMS-induced single nucleotide mutations in targeted genes or amplicons and identification of large genomic changes, including deletions and insertions. Mutagenesis of in vitro propagated tissues requires large populations serving as starting material, and a long process to dissolve genetic mosaics (chimeras) resulting from the mutagenesis of multicellular tissues. However, treating shoot apical meristems of tissue cultured bananas with a mutagen is a commonly used practice for banana mutation breeding programmes, and still the most effective. In our previous studies, we showed that chimeras, unique mutations accumulated in different cells of the plant propagule, could be rapidly removed via isolation of shoot apical meristems and subsequent longitudinal bisection. Further, induced mutations were maintained in mutant plants for several generations. We established such systems for inducing and maintaining both point mutations caused via EMS mutagenesis as well as insertions and deletions caused by gamma irradiation and describe hereafter methods for dose selection, gamma irradiation and chimera dissolution.
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Ramírez, Luis, Xesús Nogueira, Pablo Ouro, Fermín Navarrina, Sofiane Khelladi, and Ignasi Colominas. "A Higher-Order Chimera Method Based on Moving Least Squares." In Recent Advances in CFD for Wind and Tidal Offshore Turbines, 73–82. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-11887-7_7.

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Hasabnis, Apurva, Hans Maseland, Frédéric Moens, Aleš Prachař, and Jochen Wild. "Lessons Learnt from Chimera Method Application to a Deploying Krueger Device." In Advanced Computational Methods and Design for Greener Aviation, 125–44. Cham: Springer International Publishing, 2024. http://dx.doi.org/10.1007/978-3-031-61109-4_9.

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Genuit, Fabian, Manuel Keßler, and Ewald Krämer. "Applications of a Discontinuous Galerkin Chimera Method on 3D Flow Problems." In High Performance Computing in Science and Engineering '22, 265–80. Cham: Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-46870-4_18.

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Genuit, Fabian, Manuel Keßler, and Ewald Krämer. "A Discontinuous Galerkin Chimera Method for Unsteady Flow Problems on Moving Grids." In Notes on Numerical Fluid Mechanics and Multidisciplinary Design, 604–14. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-79561-0_57.

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Burggraf, U., M. Kuntz, and B. Schöning. "Implementation of the Chimera Method in the Unstructured DLR Finite Volume Code Tau." In Notes on Numerical Fluid Mechanics (NNFM), 93–100. Wiesbaden: Vieweg+Teubner Verlag, 1999. http://dx.doi.org/10.1007/978-3-663-10901-3_13.

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Wurst, M., M. Kessler, and E. Krämer. "A High-Order Discontinuous Galerkin Chimera Method for the Euler and Navier-Stokes Equations." In Notes on Numerical Fluid Mechanics and Multidisciplinary Design, 423–33. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-12886-3_19.

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Gand, F., and V. Brunet. "Zonal Detached Eddy Simulation of the Flow Downstream of a Spoiler Using the Chimera Method." In Progress in Hybrid RANS-LES Modelling, 389–99. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-31818-4_34.

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Conference papers on the topic "Chimera method"

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Pape, Arnaud, Simon Verley, and Daniel Destarac. "Far-Field Analysis of Hovering Helicopter Rotor." In Vertical Flight Society 71st Annual Forum & Technology Display, 1–11. The Vertical Flight Society, 2015. http://dx.doi.org/10.4050/f-0071-2015-10112.

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This paper presents the evaluation of the far-field drag analysis and its application to helicopter rotor in hover. This method widely used for fixed-wing configurations has only recently been extended to rotary wing in S. Verley's PhD thesis. Based on these developments, the far-field torque analysis is applied to a realistic rotor case including the blade root area using three different grid topologies: a coarse monoblock grid, a medium multiblock grid and a fine chimera grid. Near-field predictions are obtained through standard integration while Far-field results are obtained using the proposed present approach. Comparisons of near-field and far-field results are presented and discussed. The far-field breakdown is in particular detailed and it is demonstrated how the far-field analysis can be used to locate rotor torque sources.
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Zhao, Xiang, and Sijun Zhang. "An Overset Chimera Unstructured Grid Method and Its Applications." In ASME/JSME 2007 5th Joint Fluids Engineering Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/fedsm2007-37124.

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In this paper, an overset Chimera method is extended to unstructured mesh, the unstructured grid solver enhanced by the overset Chimera method is employed to various specific applications, in which time dependent fluid flows involving multiple moving bodies needs to be solved. The present method possesses not only the novel feature of Chimera method but also the advantage of unstructured grid approach. Its robustness and efficiency are illustrated in this paper through typical applications.
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Zhao, X., P. G. Richards, and S. J. Zhang. "A parallel unstructured Chimera grid method." In the 42nd annual Southeast regional conference. New York, New York, USA: ACM Press, 2004. http://dx.doi.org/10.1145/986537.986609.

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Zhang, Sijun, and Fritz Owens. "A Parallel Unstructured Chimera Grid Method." In 17th AIAA Computational Fluid Dynamics Conference. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2005. http://dx.doi.org/10.2514/6.2005-4877.

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Juvigny, Xavier, Elodie Canonne, and Christophe Benoit. "Multigrid Algorithms for the Chimera Method." In 42nd AIAA Aerospace Sciences Meeting and Exhibit. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2004. http://dx.doi.org/10.2514/6.2004-758.

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Wukie, Nathan A., Paul D. Orkwis, and Christopher R. Schrock. "A Chimera-based, zonal discontinuous Galerkin method." In 23rd AIAA Computational Fluid Dynamics Conference. Reston, Virginia: American Institute of Aeronautics and Astronautics, 2017. http://dx.doi.org/10.2514/6.2017-3947.

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Jeanfaivre, Gaelle, Christophe Benoit, and Marie-Claire Le Pape. "Improvement of the Robustness of the Chimera Method." In 32nd AIAA Fluid Dynamics Conference and Exhibit. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2002. http://dx.doi.org/10.2514/6.2002-3290.

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Galbraith, Marshall C., Paul D. Orkwis, and John A. Benek. "A 3-D Discontinuous Galerkin Chimera Overset Method." In 52nd Aerospace Sciences Meeting. Reston, Virginia: American Institute of Aeronautics and Astronautics, 2014. http://dx.doi.org/10.2514/6.2014-0776.

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Zhang, Sijun, Jiwen Liu, Yensen Chen, and Xiang Zhao. "An Unstructured Chimera Grid Method for Moving Geometries." In 43rd AIAA Aerospace Sciences Meeting and Exhibit. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2005. http://dx.doi.org/10.2514/6.2005-323.

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Zhao, Xiang, Huanwen Guan, Zhi Yang, and Sijun Zhang. "An Implicit and Globally Conservative Unstructured Chimera Grid Method." In 49th AIAA Aerospace Sciences Meeting including the New Horizons Forum and Aerospace Exposition. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2011. http://dx.doi.org/10.2514/6.2011-777.

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Reports on the topic "Chimera method"

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Kumar, Aishani, Thendral Yalini, and Sunil Kumar C. Unlocking Cellular Control: The Promise of PROTACs in Disease Intervention. Science Reviews - Biology, May 2024. http://dx.doi.org/10.57098/scirevs.biology.3.2.1.

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The discovery of proteolysis-targeting chimeras (PROTACs) is among the most exciting and promising avenues in cancer therapy. These fascinating compounds signify a paradigm shift from traditional approaches to medication development, offering a new idea that leverages the complexities of biological mechanisms to accomplish highly focused degradation of particular proteins implicated in pathological processes. This novel strategy has the potential to address a number of drawbacks with conventional therapy techniques, such as the development of drug resistance and unexpected adverse effects resulting from interactions that are not intended. The fundamental attraction of PROTACs is their distinct mode of action, which is based on controlling the cell's own machinery for protein degradation. This orchestrated degradation translates to a substantial reduction in the levels of disease-driving proteins, often leading to the disruption of critical pathways involved in cancer growth and progression. The in-depth principles underlying PROTAC technology are thoroughly explored in this review study, which also provides insight into the complex chemical mechanisms that enable these chimeric molecules to specifically degrade certain proteins while leaving others intact. Showcasing the potential of PROTACs as a revolutionary force in targeted cancer therapy, and focusing on its application in prostate and breast cancer especially, the article draws from a comprehensive compilation of preclinical and clinical studies, advancements, and breakthroughs in the field. The methods used to create and refine PROTACs for various cancer types will be examined throughout the review, along with the subtleties of the ligand and linker choices that are crucial to their effectiveness and selectivity. The difficulties and possibilities of transferring this ground-breaking technology from the lab to clinical practice will also be thoroughly examined, with an emphasis on issues like bioavailability, administration strategies, and potential resistance mechanisms. Through the integration of perspectives from various studies, the objective is to present a thorough but succinct review of the state of ongoing PROTAC research, emphasizing both, noteworthy advancements and the important issues that still need to be resolved. In the end, our investigation into PROTACs aims to shed light on how they can change the face of cancer therapy by providing a preview of a day when targeted protein degradation of disease-causing proteins would lead the way in novel therapeutic approaches.
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Davidson, Irit, Hsing-Jien Kung, and Richard L. Witter. Molecular Interactions between Herpes and Retroviruses in Dually Infected Chickens and Turkeys. United States Department of Agriculture, January 2002. http://dx.doi.org/10.32747/2002.7575275.bard.

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Tumors in commercial poultry are caused mainly by infection with avian herpes and retroviruses, the herpesvirus Marek's disease virus (MDV) and the retroviruses, reticuloendotheliosis (REV), lymphoid leukosis, subgroups A-I and J (ALV and ALV-J) in chickens, or Iymphoprolipherative disease (LPDV) in turkeys. Infection with one virus aggravates the clinical outcome of birds that are already infected by another oncogenic virus. As these viruses do not interfere for infection, MDV and one or more retroviruses can infect the same flock, the same bird and the same cell. While infecting the same cell, herpes and retroviruses might interact in at least three ways: a) Integration of retrovirus genomes, or genomic fragments (mainly the LTR) into MDV;b) alteration of LTR-driven expression of retroviral genes by MDV immediate- early genes, and c) by herpesvirus induced cellular transcriptional factors. The first type of molecular interaction have been demonstrated to happen efficiently in vitro by Dr. Kung, in cases multiple infection of cell cultures with MDV and REV or MDV and ALV. Moreover, Dr. Witter showed that an in vitro-created recombinant, RM1, had altered in vitro replication and in vivo biological properties. A more comprehensive characterization of RM1 was carried out in the present project. We sought to highlight whether events of such integrations occur also in the bird, in vivo. For that, we had first to determine the prevalence of dually-infected individual birds in commercial flocks, as no systematic survey has been yet reported. Surprisingly, about 25% of the commercial flocks infected with avian oncogenic viruses had a multiple virus infection and 5% of the total samples ana lysed had multiple virus sequences. Then, we aimed to evaluate and characterize biologically and molecularly the resulting recombinants, if formed, and to analyse the factors that affect these events (virus strains, type and age of birds and time interval between the infection with both viruses). The perception of retrovirus insertions into herpesviruses in vivo is not banal, as the in vivo and in vitro systems differ in the viral-target cells, lymphocytes or fibroblasts, in the MDV-replicative type, transforming or productive, and the immune system presence. We realized that previous methods employed to study in vitro created recombinant viruses were not adequate for the study of samples taken directly from the bird. Therefore, the Hot Spot-combined PCR was developed based on the molecularly known RM1 virus. Also, the PFGE that was used for tissue cultured-MDV separation was inefficient for separating MDV from organs, but useful with feather tips as a source of bird original MDV. Much attention was dedicated now to feathers, because if a recombinant virus would be formed in vivo, its biological significance would be evident by horizontal dissemination through the feathers. Major findings were: a) not only in vitro, but also in vivo MDV and retrovirus co-infections lead to LTR integrations into MDV. That was shown by the detection of chimeric molecules. These appeared in low quantities and as quasispecies, thus interfering with sequence analysis of cloned gel-purified chimeric molecules. Mainly inserts were located in the repeat long MDV fragments. In field birds chimeric molecules were detected at a lower frequency (2.5%) than in experimentally infected birds (30-50%). These could be transmitted experimentally to another birds by inoculation with chimeric molecules containing blood. Several types of chimeric molecules were formed, and same types were detected in birds infected by a second round. To reproduce viral integrations, in vivo infection trials were done with field inoculate that contained both viruses, but the chimeric molecule yield was undetectable.
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Gurevitz, Michael, Michael E. Adams, Boaz Shaanan, Oren Froy, Dalia Gordon, Daewoo Lee, and Yong Zhao. Interacting Domains of Anti-Insect Scorpion Toxins and their Sodium Channel Binding Sites: Structure, Cooperative Interactions with Agrochemicals, and Application. United States Department of Agriculture, December 2001. http://dx.doi.org/10.32747/2001.7585190.bard.

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Integrated pest management in modern crop protection may combine chemical and biological insecticides, particularly due to the risks to the environment and livestock arising from the massive use of non-selective chemicals. Thus, there is a need for safer alternatives, which target insects more specifically. Scorpions produce anti-insect selective polypeptide toxins that are biodegradable and non-toxic to warm-blooded animals. Therefore, integration of these substances into insect pest control strategies is of major importance. Moreover, clarification of the molecular basis of this selectivity may provide valuable information pertinent to their receptor sites and to the future design of peptidomimetic anti-insect specific substances. These toxins may also be important for reducing the current overuse of chemical insecticides if they produce a synergistic effect with conventional pesticides. Based on these considerations, our major objectives were: 1) To elucidate the three-dimensional structure and toxic-site of scorpion excitatory, "depressant, and anti-insect alpha toxins. 2) To obtain an initial view to the sodium channel recognition sites of the above toxins by generating peptide decoys through a phage display system. 3) To investigate the synergism between toxins and chemical insecticides. Our approach was to develop a suitable expression system for toxin production in a recombinant form and for elucidation of toxin bioactive sites via mutagenesis. In parallel, the mode of action and synergistic effects of scorpion insecticidal toxins with pyrethroids were studied at the sodium channel level using electrophysiological methods. Objective 1 was achieved for the alpha toxin, LqhaIT Zilberberg et al., 1996, 1997; Tugarinov et al., 1997; Froy et al., 2002), and the excitatory toxin, Bj-xtrIT (Oren et al., 1998; Froy et al., 1999; unpublished data). The bioactive surface of the depressant toxin, LqhIT2, has been clarified and a crystal of the toxin is now being analyzed (unpublished). Objective 2 was not successful thus far as no phages that recognize the toxins were obtained. We therefore initiated recently an alternative approach, which is introduction of mutations into recombinant channels and creation of channel chimeras. Objective 3 was undertaken at Riverside and the results demonstrated synergism between LqhaIT or AaIT and pyrethroids (Lee et al., 2002). Furthermore, negative cross-resistance between pyrethroids and scorpion toxins (LqhaIT and AaIT) was demonstrated at the molecular level. Although our study did not yield a product, it paves the way for future design of selective pesticides by capitalizing on the natural competence of scorpion toxins to distinguish between sodium channels of insects and vertebrates. We also show that future application of anti-insect toxins may enable to decrease the amounts of chemical pesticides due to their synergism.
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Chimera-free, high copy number YAC libraries and efficient methods of analysis. Office of Scientific and Technical Information (OSTI), January 1992. http://dx.doi.org/10.2172/7022993.

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Chimera-free, high copy number YAC libraries and efficient methods of analysis. Technical progress report. Office of Scientific and Technical Information (OSTI), December 1992. http://dx.doi.org/10.2172/10130102.

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Chimera-free, high copy number YAC libraries and efficient methods of analysis. Final technical progress report. Office of Scientific and Technical Information (OSTI), October 1995. http://dx.doi.org/10.2172/119908.

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