Academic literature on the topic 'Cell state transition'

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Journal articles on the topic "Cell state transition"

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Schramm, Vern L. "Enzymatic Transition State Theory and Transition State Analogue Design." Journal of Biological Chemistry 282, no. 39 (August 9, 2007): 28297–300. http://dx.doi.org/10.1074/jbc.r700018200.

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Gravenmier, Curtis, Ling Zhang, Lynn Moscinski, and Jeffrey West. "Abstract PR008: Cell state transitions drive the evolution of disease progression in B-cell acute lymphoblastic leukemia." Cancer Research 84, no. 3_Supplement_2 (February 1, 2024): PR008. http://dx.doi.org/10.1158/1538-7445.canevol23-pr008.

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Abstract A mathematical framework is constructed to predict the risk of B-lymphoblastic leukemia (B-ALL) relapse post-induction chemotherapy. The framework is a Markov chain model that quantifies spontaneous cell state transitions between distinct immunophenotypic subpopulations defined by CD34 and CD38 expression relative to neutrophils. Cell states are analyzed via flow cytometry pre- and post-treatment, providing insight into the evolution of cell state transition rates during disease progression. Cancer stem cells (CSCs) are hypothesized to promote tumor progression through innate chemoresistance and self-renewal. Ostensible CSCs were first identified in acute myeloid leukemia and were found to have a CD34+/CD38- immunophenotype similar to hematopoietic stem cells. However, the isolation of CSCs from B-ALL has proved more difficult. B-ALL cells with stem cell-like properties have been reported with variable immunophenotype, perhaps due to temporal variation of CD34 and CD38 expression in this setting. We hypothesized that transitions between stem cell-like, hematogone-like, and naive B-cell-like leukemia subpopulations play a significant role in B-ALL disease progression. To test this hypothesis, we trained a Markov chain mathematical model using flow cytometry characterization of four B-ALL cell states with their normal counterpart appearing in parentheses: CD34+/CD38- (hematopoietic stem cells), CD34+/CD38+ (stage 1 hematogones), CD34-/CD38+ (stage 2 and 3 hematogones), and CD34-/CD38- (naïve B-cells). An iterative numerical search procedure was used to derive patient-specific Markov matrices, describing the stochastic cell state transitions. This flow cytometry evaluation was performed on a cohort of patient samples of peripheral blood (N=46) and bone marrow (N=63) with matched clinical features such as BCR::ABL1 status, comprehensive genomic profiling, minimal residual disease (MRD) post-induction chemotherapy, and 3-year relapse. Critical to our goal of quantifying the evolution of state transition rates, we also obtained bone marrow measurements for a cohort of normal/healthy individuals. Patients were divided into post-induction flow MRD positive (N=16), MRD negative (N=30), healthy (N=6) cohorts, as well as relapsed and non-relapsed cohorts to compare features of the transition matrices. Importantly, pre-treatment flow cytometry derived cell state distribution alone is not predictive of relapse or MRD. In contrast, pre-treatment Markov chain transition parameters are found to be clinically predictive of relapse and MRD. MRD correlates to high reciprocity (the product of incoming and outgoing transitions) of the stem cell state. This approach provides supporting evidence that cell state transitions drive B-ALL disease progression. There is an additional strong correlation between Markov transition parameters and both BCR::ABL1 and BCR::ABL1-like B-ALL classification. Finally, comparison of Markov parameters pre- and post-treatment quantifies the evolutionary selection pressures acting on transition rates induced by chemotherapy treatment. Citation Format: Curtis Gravenmier, Ling Zhang, Lynn Moscinski, Jeffrey West. Cell state transitions drive the evolution of disease progression in B-cell acute lymphoblastic leukemia [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Translating Cancer Evolution and Data Science: The Next Frontier; 2023 Dec 3-6; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_2):Abstract nr PR008.
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Brackston, Rowan D., Eszter Lakatos, and Michael P. H. Stumpf. "Transition state characteristics during cell differentiation." PLOS Computational Biology 14, no. 9 (September 20, 2018): e1006405. http://dx.doi.org/10.1371/journal.pcbi.1006405.

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Wang, Ping, Chaoming Song, Hang Zhang, Zhanghan Wu, Xiao-Jun Tian, and Jianhua Xing. "Epigenetic state network approach for describing cell phenotypic transitions." Interface Focus 4, no. 3 (June 6, 2014): 20130068. http://dx.doi.org/10.1098/rsfs.2013.0068.

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Recent breakthroughs of cell phenotype reprogramming impose theoretical challenges on unravelling the complexity of large circuits maintaining cell phenotypes coupled at many different epigenetic and gene regulation levels, and quantitatively describing the phenotypic transition dynamics. A popular picture proposed by Waddington views cell differentiation as a ball sliding down a landscape with valleys corresponding to different cell types separated by ridges. Based on theories of dynamical systems, we establish a novel ‘epigenetic state network’ framework that captures the global architecture of cell phenotypes, which allows us to translate the metaphorical low-dimensional Waddington epigenetic landscape concept into a simple-yet-predictive rigorous mathematical framework of cell phenotypic transitions. Specifically, we simplify a high-dimensional epigenetic landscape into a collection of discrete states corresponding to stable cell phenotypes connected by optimal transition pathways among them. We then apply the approach to the phenotypic transition processes among fibroblasts (FBs), pluripotent stem cells (PSCs) and cardiomyocytes (CMs). The epigenetic state network for this case predicts three major transition pathways connecting FBs and CMs. One goes by way of PSCs. The other two pathways involve transdifferentiation either indirectly through cardiac progenitor cells or directly from FB to CM. The predicted pathways and multiple intermediate states are supported by existing microarray data and other experiments. Our approach provides a theoretical framework for studying cell phenotypic transitions. Future studies at single-cell levels can directly test the model predictions.
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Buder, Thomas, Andreas Deutsch, Michael Seifert, and Anja Voss-Böhme. "CellTrans: An R Package to Quantify Stochastic Cell State Transitions." Bioinformatics and Biology Insights 11 (January 1, 2017): 117793221771224. http://dx.doi.org/10.1177/1177932217712241.

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Many normal and cancerous cell lines exhibit a stable composition of cells in distinct states which can, e.g., be defined on the basis of cell surface markers. There is evidence that such an equilibrium is associated with stochastic transitions between distinct states. Quantifying these transitions has the potential to better understand cell lineage compositions. We introduce CellTrans, an R package to quantify stochastic cell state transitions from cell state proportion data from fluorescence-activated cell sorting and flow cytometry experiments. The R package is based on a mathematical model in which cell state alterations occur due to stochastic transitions between distinct cell states whose rates only depend on the current state of a cell. CellTrans is an automated tool for estimating the underlying transition probabilities from appropriately prepared data. We point out potential analytical challenges in the quantification of these cell transitions and explain how CellTrans handles them. The applicability of CellTrans is demonstrated on publicly available data on the evolution of cell state compositions in cancer cell lines. We show that CellTrans can be used to (1) infer the transition probabilities between different cell states, (2) predict cell line compositions at a certain time, (3) predict equilibrium cell state compositions, and (4) estimate the time needed to reach this equilibrium. We provide an implementation of CellTrans in R, freely available via GitHub ( https://github.com/tbuder/CellTrans ).
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Chu, Xiakun, and Jin Wang. "Insights into the cell fate decision-making processes from chromosome structural reorganizations." Biophysics Reviews 3, no. 4 (December 2022): 041402. http://dx.doi.org/10.1063/5.0107663.

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The cell fate decision-making process, which provides the capability of a cell transition to a new cell type, involves the reorganizations of 3D genome structures. Currently, the high temporal resolution picture of how the chromosome structural rearrangements occur and further influence the gene activities during the cell-state transition is still challenging to acquire. Here, we study the chromosome structural reorganizations during the cell-state transitions among the pluripotent embryonic stem cell, the terminally differentiated normal cell, and the cancer cell using a nonequilibrium landscape-switching model implemented in the molecular dynamics simulation. We quantify the chromosome (de)compaction pathways during the cell-state transitions and find that the two pathways having the same destinations can merge prior to reaching the final states. The chromosomes at the merging states have similar structural geometries but can differ in long-range compartment segregation and spatial distribution of the chromosomal loci and genes, leading to cell-type-specific transition mechanisms. We identify the irreversible pathways of chromosome structural rearrangements during the forward and reverse transitions connecting the same pair of cell states, underscoring the critical roles of nonequilibrium dynamics in the cell-state transitions. Our results contribute to the understanding of the cell fate decision-making processes from the chromosome structural perspective.
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Ichimura, Taro, Liang-da Chiu, Katsumasa Fujita, Satoshi Kawata, Tomonobu M. Watanabe, Toshio Yanagida, and Hideaki Fujita. "Visualizing Cell State Transition Using Raman Spectroscopy." PLoS ONE 9, no. 1 (January 7, 2014): e84478. http://dx.doi.org/10.1371/journal.pone.0084478.

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Huang, Rongsheng, and Jinzhi Lei. "Dynamics of gene expression with positive feedback to histone modifications at bivalent domains." International Journal of Modern Physics B 32, no. 07 (March 5, 2018): 1850075. http://dx.doi.org/10.1142/s0217979218500753.

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Experiments have shown that in embryonic stem cells, the promoters of many lineage-control genes contain “bivalent domains”, within which the nucleosomes possess both active (H3K4me3) and repressive (H3K27me3) marks. Such bivalent modifications play important roles in maintaining pluripotency in embryonic stem cells. Here, to investigate gene expression dynamics when there are regulations in bivalent histone modifications and random partition in cell divisions, we study how positive feedback to histone methylation/demethylation controls the transition dynamics of the histone modification patterns along with cell cycles. We constructed a computational model that includes dynamics of histone marks, three-stage chromatin state transitions, transcription and translation, feedbacks from protein product to enzymes to regulate the addition and removal of histone marks, and the inheritance of nucleosome state between cell cycles. The model reveals how dynamics of both nucleosome state transition and gene expression are dependent on the enzyme activities and feedback regulations. Results show that the combination of stochastic histone modification at each cell division and the deterministic feedback regulation work together to adjust the dynamics of chromatin state transition in stem cell regenerations.
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Gopal, Priyanka, Aaron Petty, Kevin Rogacki, Titas Bera, Rohan Bareja, Craig Peacock, and Mohamed Abazeed. "Abstract 2229: Cell state transitions shape the intratumoral composition of small cell lung carcinoma." Cancer Research 83, no. 7_Supplement (April 4, 2023): 2229. http://dx.doi.org/10.1158/1538-7445.am2023-2229.

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Abstract Introduction: Small cell lung carcinoma (SCLC) is characterized by rapid growth, early metastases, and initial response followed by almost invariable resistance to therapy. Studies to date have not determined the extent that diverse transcriptional programs drive SCLC and contribute to its lethality. We sought to characterize the intra-tumoral transcriptional heterogeneity of SCLC. We identify multivalent, distinct, and commutable transcriptional states that confer discrete functions in individual SCLC tumors. Methods: We developed a biorepository of patient-derived xenografts (PDX) (n = 64) and matched PDX-derived ex vivo lines. We used multi-omic profiling (RNAseq, scRNAseq, and ATAC seq), single-cell fluorescence tracking of fate-defining transcription factor (TF)-driven states, and mathematical and statistical models (Markov chain) to study the topology of the SCLC transcriptional landscape and its plasticity. Human tumor material and associated clinical data were obtained after informed written consent on an IRB-approved prospective registry. Results: We show that individual SCLC tumors are more heterogenous than previously appreciated, displaying distinctive equilibria in the proportion of cells within well-delimited cellular states (ASCL1, NEUROD1 and YAP1). We also show that transcriptional states undergo transitions, which we identified as a mechanism for maintaining cell state diversity. We measured the kinetics of state transitions using single-cell fluorescence tracking of ex vivo cultures and found that these measure were associated significantly with transition estimates using stochastic transition theory (i.e. Markov chains). ATAC-seq profiling indicated a role for the epigenome in the state diversity of SCLC. Namely, there was preferential promoter accessibility to Ascl1, NeuroD1, and Yap1 in a manner consistent with gene and protein expression in the respective subpopulations. Our results indicate that the transition rates between cell types in individual tumors were largely governed by tendencies to reach an equilibrium state that are critical for configuring intratumoral cell state proportions. Conclusion: In conclusion, we demonstrate that TF driven cell states can transition to maintain an equilibrium in cell state proportions. Our work advances a model of cellular states and program diversity in SCLC and nominates new therapeutic strategies designed to limit the plasticity of this lethal cancer. Citation Format: Priyanka Gopal, Aaron Petty, Kevin Rogacki, Titas Bera, Rohan Bareja, Craig Peacock, Mohamed Abazeed. Cell state transitions shape the intratumoral composition of small cell lung carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2229.
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Jagannathan, N. Suhas, Mario O. Ihsan, Xiao Xuan Kin, Roy E. Welsch, Marie-Véronique Clément, and Lisa Tucker-Kellogg. "Transcompp: understanding phenotypic plasticity by estimating Markov transition rates for cell state transitions." Bioinformatics 36, no. 9 (January 23, 2020): 2813–20. http://dx.doi.org/10.1093/bioinformatics/btaa021.

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Abstract Motivation Gradual population-level changes in tissues can be driven by stochastic plasticity, meaning rare stochastic transitions of single-cell phenotype. Quantifying the rates of these stochastic transitions requires time-intensive experiments, and analysis is generally confounded by simultaneous bidirectional transitions and asymmetric proliferation kinetics. To quantify cellular plasticity, we developed Transcompp (Transition Rate ANalysis of Single Cells to Observe and Measure Phenotypic Plasticity), a Markov modeling algorithm that uses optimization and resampling to compute best-fit rates and statistical intervals for stochastic cell-state transitions. Results We applied Transcompp to time-series datasets in which purified subpopulations of stem-like or non-stem cancer cells were exposed to various cell culture environments, and allowed to re-equilibrate spontaneously over time. Results revealed that commonly used cell culture reagents hydrocortisone and cholera toxin shifted the cell population equilibrium toward stem-like or non-stem states, respectively, in the basal-like breast cancer cell line MCF10CA1a. In addition, applying Transcompp to patient-derived cells showed that transition rates computed from short-term experiments could predict long-term trajectories and equilibrium convergence of the cultured cell population. Availability and implementation Freely available for download at http://github.com/nsuhasj/Transcompp. Supplementary information Supplementary data are available at Bioinformatics online.
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Dissertations / Theses on the topic "Cell state transition"

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Lu, Xibin, and 盧希彬. "Quantitative characterization of mouse embryonic stem cell state transition." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/208049.

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Alwosaibai, Kholoud. "Role of PAX2 in Maintaining the Differentiation of Oviductal Epithelium and Inhibiting the Transition to a Stem Cell State." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34450.

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Several studies have proposed the fallopian tube epithelium as a site of origin of ovarian cancer. The discovery of precursor lesions in the fallopian tube in patients at risk for ovarian cancer supports a probable origin for high-grade serous ovarian carcinoma in this tissue. While the fallopian tube epithelium consists of three distinct cell types, the paired box protein 2 (PAX2) positive cells and potentially the CD44 positive stem-like cells are most relevant to ovarian cancer. Loss of PAX2 expression in the fallopian tube cells is considered to be an early event in epithelial transformation, but the specific role of PAX2 in this transition is unknown. The aim of this study was to define the role of PAX2 in oviductal epithelial cells (OVE) cells and in mouse ovarian surface epithelial cells (MOSE), and to understand its contribution to the formation of serous precursor lesions in the fallopian tubes. Herein, we studied the OVE response to transforming growth factor β (TGFβ, a cytokine found in follicular fluid) and provide evidence of its potential involvement in the regulation of stem cell-like behaviors that may contribute to formation of cancer-initiating cells. Treatment of primary cultures of OVE cells with TGFβ at concentrations found in ovulatory follicular fluid induced an epithelial-mesenchymal transition (EMT) with expected changes in proliferation, cell morphology and expression of SNAIL, Vimentin and E-cadherin. EMT was also associated with decreased expression of PAX2 and an increase in the fraction of cells expressing CD44. Pax2 knockdown in OVE cells and overexpression in ovarian epithelial cells confirmed that PAX2 inhibits CD44 expression and regulates the degree of epithelial differentiation of OVE cells. These results suggest that the loss of PAX2 seen in serous tubal intraepithelial carcinomas (STIC) leads to a shift to a more mesenchymal phenotype associated with stem-like features. Pax2 overexpression in MOSE cells also induced the formation of vascular channels both in vitro and in vivo, which indicate a possible contribution of PAX2 to ovarian cancer progression by increasing the vascular channels to supply nutrients to the tumor cells. Furthermore, since loss of PAX2 in STIC was found associated with P53 and BRCA1 mutations, OVE cells with mutations of the tumor suppressor genes Trp53 and Brca1 were studied. We found that loss of Trp53 with or without loss of Brca1 increased cell proliferation and colony formation in vitro. In addition, loss of Trp53 induced OVE cells to undergo EMT and induced the expression of stem cell–associated genes. We therefore suggest a potential contribution of stem cells in initiating the precursor lesions in the fallopian tubes in combination with tumor suppressor gene mutation.
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Bokun, G. S., Ya G. Groda, R. N. Lasovsky, and V. S. Vikhrenko. "Charge Distribution Around Nanoscale Nonhomogeneities in Solid State Ionics." Thesis, Sumy State University, 2015. http://essuir.sumdu.edu.ua/handle/123456789/42717.

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The system of Nernst-Planck-Poisson equations is modified by including the gradient terms in the chemical potential expression. The gradient terms are important in the regions of significant inhomogeneities, e. g. near the interface boundaries. These modified equations are used for investigating the particle density distribution in the vicinity of interphase boundary of a solid electrolyte. The differential equation of the fourth order for the problem of contact between two solid phases is formulated. Its analytic solution which describes non monotonic distribution of charge in both phases is obtained. It is shown that the gradient component added in the transport equations makes a decisive contribution in the double layer region. The approach is further expanded to the system composed of bulk phases and the intergrain layer between them. The particle density distributions at different conditions are investigated. The quasy-one dimensional lattice model of the fuel cell is considered in the frame of kinetic Monte Carlo simulation. It is shown that the electrostatic interaction between ions makes a significant contribution to the activation energy of migration of the particles. On the other hand, the fluctuations of the energy barriers slightly increase the particle migration activation energy. It is found that at blocked electrodes in the near electrode regions electrical double layers are formed. The thickness of the electrical double layer is around few lattice constants.
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Nicetto, Dario [Verfasser], and Peter [Akademischer Betreuer] Becker. "On the way to differentiation : xenopus Suv4-20h histone methyltransferases regulate the transition from the pluripotent to the ectoderm cell state / Dario Nicetto. Betreuer: Peter Becker." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2012. http://d-nb.info/1029662428/34.

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Hrubiak, Rostislav. "Exploring Thermal and Mechanical Properties of Selected Transition Elements under Extreme Conditions: Experiments at High Pressures and High Temperatures." FIU Digital Commons, 2012. http://digitalcommons.fiu.edu/etd/696.

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Transition metals (Ti, Zr, Hf, Mo, W, V, Nb, Ta, Pd, Pt, Cu, Ag, and Au) are essential building units of many materials and have important industrial applications. Therefore, it is important to understand their thermal and physical behavior when they are subjected to extreme conditions of pressure and temperature. This dissertation presents: An improved experimental technique to use lasers for the measurement of thermal conductivity of materials under conditions of very high pressure (P, up to 50 GPa) and temperature (T up to 2500 K). An experimental study of the phase relationship and physical properties of selected transition metals, which revealed new and unexpected physical effects of thermal conductivity in Zr, and Hf under high P-T. New phase diagrams created for Hf, Ti and Zr from experimental data. P-T dependence of the lattice parameters in α-hafnium. Contrary to prior reports, the α-ω phase transition in hafnium has a negative dT/dP slope. New data on thermodynamic and physical properties of several transition metals and their respective high P-T phase diagrams. First complete thermodynamic database for solid phases of 13 common transition metals was created. This database has: All the thermochemical data on these elements in their standard state (mostly available and compiled). All the equations of state (EoS) formulated from pressure-volume-temperature data (measured as a part of this study and from literature). Complete thermodynamic data for selected elements from standard to extreme conditions. The thermodynamic database provided by this study can be used with available thermodynamic software to calculate all thermophysical properties and phase diagrams at high P-T conditions. For readers who do not have access to this software, tabulated values of all thermodynamic and volume data for the 13 metals at high P-T are included in the APPENDIX. In the APPENDIX, a description of several other high-pressure studies of selected oxide systems is also included. Thermophysical properties (Cp, H, S, G) of the high P-T ω-phase of Ti, Zr and Hf were determined during the optimization of the EoS parameters and are presented in this study for the first time. These results should have important implications in understanding hexagonal-close-packed to simple-hexagonal phase transitions in transition metals and other materials.
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Kotelnikova, Alena. "Analysis of a hydrogen-based transport system and the role of public policy in the transition to a decarbonised economy." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLX057/document.

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Quel cadre économique et réglementaire à long terme (2030-50) pour soutenir la transition énergétique des carburants fossiles vers l’hydrogène dans le secteur européen des transports ? Cette recherche combine les approches théoriques et empiriques pour répondre aux trois questions suivantes :1. Comment concevoir des politiques de soutien adaptées pour pallier les imperfections de marché lors du déploiement de technologies de mobilité hydrogène ?2. Comment modéliser les coûts d’abattement en tenant compte des effets d’apprentissage (LBD) ?3. Comment définir la trajectoire optimale de déploiement quand le LBD et la convexité des coûts d’investissement sont présents ?L’article ‘Transition vers un Système de Transport de Passagers à Hydrogène : Analyse Politique Comparée’ passe au crible des politique de soutien destinées à résoudre les imperfections de marché dans le déploiement de la mobilité hydrogène. L’article effectue une comparaison internationale entre les instruments en faveur du déploiement des véhicules. Les indicateurs ex post d’efficacité des politiques sont développés et calculés pour classifier les pays selon leur volontarisme dans la promotion des véhicules à piles à combustible (FCEV). Aujourd’hui le Japon et le Danemark apparaissent comme les meilleurs fournisseurs d’un environnement favorable au déploiement de la mobilité hydrogène. Les autorités locales introduisent de solides instruments prix (tels que des subventions et des exemptions fiscales) pour rendre le FCEV plus attractif par rapport à son analogue à essence et coordonnent le déploiement de l’infrastructure hydrogène sur le territoire.L’article ‘Modélisation des Coûts d’Abattement en Présence d’Effets d’Apprentissage : le Cas du Véhicule à Hydrogène’ présente un modèle de transition du secteur des transports d’un état polluant à un état propre. Un modèle d’équilibre partiel est développé pour un secteur automobile de taille constante. L’optimum social est atteint en minimisant le coût de la transition du parc automobile au cours du temps. Ce coût comprend les coûts privés de production des véhicules décarbonés (sujets aux effets d’apprentissage) ainsi que le coût social des émissions de CO2 qui suit une tendance haussière exogène. L’article caractérise la trajectoire optimale qui est un remplacement progressif des véhicules polluants par les décarbonés. Au cours de la transition, l’égalisation des coûts marginaux tient compte de l’impact des actions présentes sur les coûts futurs via l’effet d’apprentissage. L’article décrit aussi une trajectoire sous-optimale où la trajectoire de déploiement serait une donnée exogène : quelle serait alors la date optimale de début de la transition ? L’article présente une évaluation quantitative de la substitution des FCEV aux véhicules à combustion interne (ICE). L’analyse conclut que le FCEV deviendra une option économiquement viable pour décarboner une partie du parc automobile allemand à l’horizon 2050 dès que le prix du carbone atteindra 50-60€/t.L’article ‘Le rôle des Effets d’Apprentissage dans l’Adoption d’une Technologie Verte : le Cas LBD Linéaire’ étudie les caractéristiques d’une trajectoire optimale de déploiement des véhicules décarbonés dans le cas où les effets d’apprentissage et la convexité sont présents dans la fonction de coût. Le modèle d’équilibre partiel de Creti et. al (2015) est utilisé comme point de départ. Dans le cas LBD linéaire la trajectoire de déploiement optimale est obtenue analytiquement. Un apprentissage fort induit une transition antérieure vers les véhicules verts dans le cas d’une convexité faible et une transition ultérieure dans le cas d’une convexité forte. Ce résultat permet de revisiter le projet H2 Mobility en Allemagne. Un effet d’apprentissage plus fort et une accélération du déploiement aboutissent à une transition moins coûteuse et une période de cash flow négatif plus courte
What economic and policy framework would foster a transition in the European transport sector from fossil fuels to hydrogen in the long term (2030-50)? This research combines empirical and theoretical approaches and aims to answers the following questions:1. How to design appropriate policy instruments to solve inefficiencies in hydrogen mobility deployment?2. How to define abatement cost and an optimal launching date in the presence of learning-by-doing (LBD)?3. How to define an optimal deployment trajectory in presence of LBD and convexity in investment costs?The paper ‘Transition Towards a Hydrogen-Based Passenger Car Transport: Comparative Policy Analysis‘ draws a cross-country comparison between policy instruments that support the deployment of Fuel Cell Electric Vehicle (FCEV). The existing policy framework in favour of FCEV and hydrogen infrastructure deployment is analysed. A set of complementary ex-post policy efficiency indicators is developed and calculated to rank the most active countries, supporters of FCEV. Denmark and Japan emerge as the best providers of favourable conditions for the hydrogen mobility deployment: local authorities put in place price-based incentives (such as subsidies and tax exemptions) making FCEV more financially attractive than its gasoline substitute, and coordinate ramping-up of their hydrogen infrastructure nationally.The paper ’Defining the Abatement Cost in Presence of Learning-by-doing: Application to the Fuel Cell Electric Vehicle’ models the transition of the transport sector from a pollutant state to a clean one. A partial equilibrium model is developed for a car sector of a constant size. In this model the objective of the social planner is to minimize the cost of phasing out a stock of polluting cars from the market over time. The cost includes the private cost of green cars production, which are subject to LBD, and the social cost of carbon, which has an exogenous upward trend. During the transition, the equalization of marginal costs takes into account the fact that the current action has an impact on future costs through LBD. This paper also describes a suboptimal plan: if the deployment trajectory is exogenously given, what is the optimal starting date for the transition? The paper provides a quantitative assessment of the FCEV case for the substitution of the mature Internal Combustion Engine (ICE) vehicles. The analysis concludes that the CO2 price should reach 53€/t for the program to start and for FCEV to be a socially beneficial alternative for decarbonizing part of the projected German car park in the 2050 time frame.The impact of LBD on the timing and costs of emission abatement is, however, ambiguous. On the one hand, LBD supposes delaying abatement activities because of cost reduction of future abatement due to LBD. On the other hand, LBD supposes starting the transition earlier because of cost reduction due to added value to cumulative experience. The paper ‘The Role of Learning-by-Doing in the Adoption of a Green Technology: the Case of Linear LBD’ studies the optimal characteristics of a transition towards green vehicles in the transport sector when both LBD and convexity are present in the cost function. The partial equilibrium model of (Creti et al., 2015) is used as a starting point. For the case of linear LBD the deployment trajectory can be analytically obtained. This allows to conclude that a high learning induces an earlier switch towards green cars in the case of low convexity, and a later switch in the case of high convexity. This insight is used to revisit the hydrogen mobility project in Germany. A high learning lowers the corresponding deployment cost and reduces deepness and duration of the, investment ‘death valley’ (period of negative project’s cash flow). An acceleration of exogenously defined scenario for FCEV deployment, based on the industry forecast, would be beneficial to reduce the associated transition cost
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Grimaldi, Alexandre. "Fondements régulatoires de la diversité des muscles faciaux : origines développementales de la résilience musculaire." Electronic Thesis or Diss., Sorbonne université, 2020. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2020SORUS244.pdf.

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Les muscles squelettiques sont présents dans tout le corps et présentent un niveau surprenant d'hétérogénéité, dans leur susceptibilité aux maladies, potentiel de régénération ou capacités métaboliques. Cette diversité est également retrouvée au cours du développement embryonnaire où les cellules myogéniques et non myogéniques établissent le système musculo-squelettique. La tête et le cou sont constitués d'une grande variété de muscles qui remplissent des fonctions essentielles, mais nous en savons peu sur la biologie des muscles craniofaciaux. Ces structures sont associées à l'émergence de cellules de la crête neurale (CCN) qui donnent naissance à la plupart des tissus non myogéniques crâniens et qui sont cruciales à la formation des muscles. Cependant, certains muscles crâniens sont privés de CCN, et nous ignorons comment les cellules myogéniques et non myogéniques contribuent à ces domaines. Cette thèse fournit des preuves démontrant que les progéniteurs en amont du muscle se détournent du programme myogénique pour donner naissance au tissu conjonctif. Nous avons utilisé une approche de single-cell RNAseq non biaisée et restreinte avec différentes lignées transgéniques de souris à des stades embryonnaires distincts, des marquages in situ et de nouvelles méthodes analytiques, et avons montré que les progéniteurs bipotents issus du mésoderme exprimant le gène de détermination musculaire Myf5 donnent naissance au muscle squelettique et au tissu conjonctif anatomiquement associé dans les muscles partiellement privés de CCN. Cette transition est caractérisée par une complémentarité de signalisation de récepteurs tyrosine kinase entre les cellules musculaires et non musculaires, ainsi que par des modules régulateurs distincts. Les muscles crâniens proviennent également de différentes lignées qui impliquent l'activité de cascades de régulation génique spécifiques. Ici, nous avons utilisé une approche non biaisée et large pour découvrir des modules de régulation spécifiques qui sous-tendent différentes populations de cellules myogéniques dans la tête et à travers plusieurs stades de développement. Certaines de ces « tâches de naissance génétiques » uniques sont des facteurs de transcription spécifiques et sont conservées dans les cellules souches musculaires adultes, ce qui indique que leur importance potentielle est de fournir les propriétés uniques qui ont été signalées pour différentes populations de cellules souches musculaires. Enfin, ces études utilisent des méthodes analytiques inédites qui bénéficient des dernières avancées algorithmiques et offrent de nouvelles perspectives pour la découverte de processus biologiques à partir de données à haut débit
Skeletal muscles are found throughout the body and they display a surprising level of heterogeneity in properties and function. For example, some muscles are specifically susceptible to diseases, and some have better regenerative potential or different metabolic capacities. Diversity is also found during embryonic development where myogenic and non-myogenic cells establish the musculoskeletal system. The head and neck are comprised of a wide variety of muscles that perform essential functions such as feeding, breathing and vocalising, yet little is known about craniofacial muscle biology. Novel structures are associated with the emergence of neural crest cells (NCC) which give rise to most craniofacial connective tissue, cartilage and bone and are crucial for muscle morphogenesis. However, some cranial muscles are deprived of NCC, and it is unclear how myogenic and non-myogenic cells contribute to those domains. This thesis provides evidence demonstrating that upstream progenitors redirect from the myogenic program to give rise to the muscle-associated connective tissue that supports the formation of muscular structures. We employed unbiased and lineage-restricted single-cell RNAseq using different mouse transgenic lines at distinct embryonic stages, in situ labelling, and new analytical methods, and show that bipotent progenitors expressing the muscle determination gene Myf5 give rise to skeletal muscle and anatomically associated connective tissue in distinct muscle groups spatiotemporally. Notably, this property was restricted to muscles with only partial contribution from NCCs suggesting that in their absence, the balance of myogenic and connective tissue cells is undertaken by somite-derived or cranial-derived mesoderm. This transition is characterised by a complementarity of tyrosine kinase receptor signalling between muscle and non-muscle cells, as well as distinct regulatory modules. Cranial muscles also originate from different lineages that involve the activity of specific gene regulatory cascades. Here, we used an all-inclusive unbiased approach to uncover specific regulatory modules that underlie different myogenic cell populations in the head and across multiple developmental stages. Some of these unique “genetic birthmarks” are specific transcription factors, and are retained in adult muscle stem cells pointing to their potential importance is delivering the unique properties that have been reported for different muscle stem cell populations. Finally, these studies employ novel computational methods that benefit from the latest algorithmic advancements and they provide prospects for the discovery of new biological processes from high throughput data
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Rale, Pierre. "Multi-transition solar cells with localised states." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066541/document.

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Ce travail s’intéresse aux cellules solaires multi-transitions. Deux semiconducteurs à niveaux subbandgap : un highly mismatched alloy, le GaAsPN, et un absorbeur à boites quantiques. Les états subbandgap permettent de modifier l’énergie de gap ou de créer une bande intermédiaire au milieu du gap. En premier lieu, une introduction de la cellule solaire par l’étude de luminescence est présentée. Des liens entre luminescence et propriétés électriques sont établis, et les limites thermodynamiques de l’efficacité des dispositifs multi-transitions sont explicitées. Enfin, une méthode optique de caractérisation des cellules solaires est démontrée. La première partie expérimentale de la thèse est dédiée au développement d’une top cell en GaAsPN en accord de maille avec une bottom cell en Silicium. Des simulations numériques ont mis en évidence les difficultés à surmonter pour ce type de matériau. La dynamique des porteurs a été étudiée par photoluminescence en régime permanent et résolue en temps. Ces mesures ont mis en évidence que les absorbeurs crûs souffraient d’états fortement localisés, majoritairement dus à des clusters d’azote. Ces états nous ont permis en revanche d’étudier les propriétés de bande intermédiaire de cet alliage. Enfin, une méthode optique de caractérisation, adaptée aux IBSCs et à la mise en évidence des deux mécanismes clés de ce concept (two-step two-photon absorption et la préservation de la tension). Cette méthode a été appliquée à deux candidats pour les IBSCs, un absorbeur à multi-puits quantiques et un à boîtes quantiques. Les résultats montrent que l’absorbeur à boîtes quantiques présente un comportement compatible avec les IBSCs
This thesis deals with the multi-transition solar cells by studying two subband gap localised states materials: one highly mismatched alloy, GaAsPN, and one multi-stacked quantum dots heterostructure. These subband gap states give the possibility to tune the band gap energy or create two photon transitions inside a single the absorber. In a first part, a radiance based introduction of the solar cell is presented. Links between radiances and electrical properties are pointed out. From this analysis, the thermodynamic limits of the single and multiple transition solar cells are derived and key mechanisms for multi-transition solar cells are identified. A universal optical characterisation method for probing electrical properties of solar cells is displayed. The first experimental part of this thesis was dedicated to the development of a GaAsPN based pin top cell lattice matched with a Silicon bottom cell. Numerical simulations have been carried out. Carrier dynamics has been studied by steady-state and time-resolved photoluminescence, with the conclusion that the GaAsPN we grew still suffer from multiple strongly localised states below the band gap, mainly due to N-clusters. Finally, we have taken advantages of the strong carrier localisation for a use as an intermediate band solar cell. Eventually, a quantitative optical characterisation method was developed in order to evaluate the potential of an absorber as an IBSC. The two key processes, the two-step two-photon absorption and the voltage preservation, can be widely investigate through it. This method has been applied to two IBSC candidates, a MQW and a MSQD absorbers. The MSQD cell have shown IB compatibility
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Screaton, Robert A. "Effects of carcinoembryonic antigen (CEA) and Myc on cell state transitions." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape10/PQDD_0016/NQ55422.pdf.

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10

Rale, Pierre. "Multi-transition solar cells with localised states." Electronic Thesis or Diss., Paris 6, 2015. http://www.theses.fr/2015PA066541.

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Ce travail s’intéresse aux cellules solaires multi-transitions. Deux semiconducteurs à niveaux subbandgap : un highly mismatched alloy, le GaAsPN, et un absorbeur à boites quantiques. Les états subbandgap permettent de modifier l’énergie de gap ou de créer une bande intermédiaire au milieu du gap. En premier lieu, une introduction de la cellule solaire par l’étude de luminescence est présentée. Des liens entre luminescence et propriétés électriques sont établis, et les limites thermodynamiques de l’efficacité des dispositifs multi-transitions sont explicitées. Enfin, une méthode optique de caractérisation des cellules solaires est démontrée. La première partie expérimentale de la thèse est dédiée au développement d’une top cell en GaAsPN en accord de maille avec une bottom cell en Silicium. Des simulations numériques ont mis en évidence les difficultés à surmonter pour ce type de matériau. La dynamique des porteurs a été étudiée par photoluminescence en régime permanent et résolue en temps. Ces mesures ont mis en évidence que les absorbeurs crûs souffraient d’états fortement localisés, majoritairement dus à des clusters d’azote. Ces états nous ont permis en revanche d’étudier les propriétés de bande intermédiaire de cet alliage. Enfin, une méthode optique de caractérisation, adaptée aux IBSCs et à la mise en évidence des deux mécanismes clés de ce concept (two-step two-photon absorption et la préservation de la tension). Cette méthode a été appliquée à deux candidats pour les IBSCs, un absorbeur à multi-puits quantiques et un à boîtes quantiques. Les résultats montrent que l’absorbeur à boîtes quantiques présente un comportement compatible avec les IBSCs
This thesis deals with the multi-transition solar cells by studying two subband gap localised states materials: one highly mismatched alloy, GaAsPN, and one multi-stacked quantum dots heterostructure. These subband gap states give the possibility to tune the band gap energy or create two photon transitions inside a single the absorber. In a first part, a radiance based introduction of the solar cell is presented. Links between radiances and electrical properties are pointed out. From this analysis, the thermodynamic limits of the single and multiple transition solar cells are derived and key mechanisms for multi-transition solar cells are identified. A universal optical characterisation method for probing electrical properties of solar cells is displayed. The first experimental part of this thesis was dedicated to the development of a GaAsPN based pin top cell lattice matched with a Silicon bottom cell. Numerical simulations have been carried out. Carrier dynamics has been studied by steady-state and time-resolved photoluminescence, with the conclusion that the GaAsPN we grew still suffer from multiple strongly localised states below the band gap, mainly due to N-clusters. Finally, we have taken advantages of the strong carrier localisation for a use as an intermediate band solar cell. Eventually, a quantitative optical characterisation method was developed in order to evaluate the potential of an absorber as an IBSC. The two key processes, the two-step two-photon absorption and the voltage preservation, can be widely investigate through it. This method has been applied to two IBSC candidates, a MQW and a MSQD absorbers. The MSQD cell have shown IB compatibility
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Books on the topic "Cell state transition"

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Gottweis, Herbert. The global politics of human embryonic stem cell science: Regenerative medicine in transition. New York: Palgrave Macmillan, 2009.

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2

Transitions to alternative transportation technologies: A focus on hydrogen. Washington, D.C: National Academies Press, 2008.

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Office, General Accounting. Telecommunications: Additional federal efforts could help advance digital television transition : report to the ranking minority member, Subcommittee on Telecommunications and the Internet, Committee on Energy and Commerce, House of Representatives. [Washington, D.C.]: General Accounting Office (441 G St. NW, Room LM, Washington, 20548), 2002.

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4

Chow, Wong-Ho, Ghislaine Scelo, and Robert E. Tarone. Renal Cancer. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190238667.003.0051.

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Renal cancers in adults are classified into two major groups according to the anatomic subsite of origin. The predominant group, originating from the renal parenchyma, is mostly renal cell carcinoma, which, in turn, is further classified into morphologically, clinically, and genetically distinct subtypes. Over 75% of renal cell carcinomas are designated clear cell, which is closely linked to alterations in the VHL gene. Almost all cancers arising from the renal pelvis and ureter are urothelial carcinomas, previously known as transitional cell carcinomas. Renal cell cancer incidence rates have increased globally over the past few decades. In the United States, incidence rates among blacks have surpassed rates for whites. Modifiable risk factors such as cigarette smoking, obesity, and hypertension, are more common among blacks than whites, partly explaining the racial disparity in renal cell cancer incidence. Having a first-degree relative with kidney cancer also has been linked to a two- to five-fold elevated risk.
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Chase, Robert T. We Are Not Slaves. University of North Carolina Press, 2020. http://dx.doi.org/10.5149/northcarolina/9781469653570.001.0001.

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In the early twentieth century, the brutality of southern prisons became a national scandal. Prisoners toiled in grueling, violent conditions while housed in crude dormitories on what were effectively slave plantations. This system persisted until the 1940s when, led by Texas, southern states adopted northern prison design reforms. Texas presented the reforms to the public as modern, efficient, and disciplined. Inside prisons, however, the transition to penitentiary cells only made the endemic violence more secretive, intensifying the labor division that privileged some prisoners with the power to accelerate state-orchestrated brutality and the internal sex trade. Reformers' efforts had only made things worse--now it was up to the prisoners to fight for change. Drawing from three decades of legal documents compiled by prisoners, Robert T. Chase narrates the struggle to change prison from within. Prisoners forged an alliance with the NAACP to contest the constitutionality of Texas prisons. Behind bars, a prisoner coalition of Chicano Movement and Black Power organizations publicized their deplorable conditions as “slaves of the state” and initiated a prison-made civil rights revolution and labor protest movement. These insurgents won epochal legal victories that declared conditions in many southern prisons to be cruel and unusual--but their movement was overwhelmed by the increasing militarization of the prison system and empowerment of white supremacist gangs that, together, declared war on prison organizers. Told from the vantage point of the prisoners themselves, this book weaves together untold but devastatingly important truths from the histories of labor, civil rights, and politics in the United States as it narrates the transition from prison plantations of the past to the mass incarceration of today.
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Beckman, Thomas J., and Haitham S. Abu-Lebdeh. Men’s Health. Oxford University Press, 2012. http://dx.doi.org/10.1093/med/9780199755691.003.0465.

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Benign prostatic hyperplasia (BPH) and erectile dysfunction are among the commonest diagnoses in a men's health practice. BPH is common among older men. The prostate is the size of a walnut (20 cm3) in men younger than 30 years and it gradually increases in size, leading to BPH in most men older than 60 years. BPH results from epithelial and stromal cell growth, which begins in the transitional zone of the prostate and causes urinary outflow resistance. Over time, this resistance leads to detrusor muscle dysfunction, urinary retention, and lower urinary tract symptoms (LUTS). Male sexual dysfunction includes erectile dysfunction (ED), decreased libido, anatomical abnormalities (eg, Peyronie disease), and ejaculatory dysfunction. ED, defined as the inability to achieve erections firm enough for vaginal penetration, affects millions of men in the United States.
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MacGrogan, Donal, José Maria Pérez-Pomares, Bill Chaudhry, José Luis de la Pompa, and Deborah J. Henderson. From cushions to leaflets: morphogenesis of cardiac atrioventricular valves. Edited by José Maria Pérez-Pomares, Robert G. Kelly, Maurice van den Hoff, José Luis de la Pompa, David Sedmera, Cristina Basso, and Deborah Henderson. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780198757269.003.0017.

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At the looping stage of heart development, tissue patterning of myocardium and endocardium at the atrioventricular (AV) junction defines a morphogenic field competent to form valves that initially appear as protrusions of proteoglycan-rich extracellular matrix (ECM) called endocardial cushions (ECs) which are cellularized by an endocardial-mesenchymal transition (EMT). Cellular proliferation results in fusion of the major AV mesenchymal cushions and AV septation, whereas smaller cushions receive a supply from epicardially derived cells. These various sources of mesenchyme precursors give rise to most of the valve structures, leaflets, annuli, and supporting tension apparatus. During valve leaflet maturation, the ECM matrix accumulates collagen and elastin and assembles into a thin flexible fibrous structure, which is remarkably tough. Valve development is regulated by the cross-talk between developmental signalling pathways. Pathogenic mutations in a subset of developmentally important genes have been linked to valve disease, suggesting that developmental defects may underlie valve disease in adulthood.
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Book chapters on the topic "Cell state transition"

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Cornelius, V. J., P. J. Titler, G. R. Fern, J. R. Miller, J. Silver, M. J. Snowden, and C. A. Mccammon. "An Interesting Spin-State Transition for [Fe(PPIX)OH] Induced by High Pressure in a Diamond Anvil Cell." In Mössbauer Spectroscopy, 359–63. Dordrecht: Springer Netherlands, 2003. http://dx.doi.org/10.1007/978-94-010-0045-1_34.

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Tsuchiya, Masa, Alessandro Giuliani, and Paul Brazhnik. "From Cell States to Cell Fates: Control of Cell State Transitions." In Methods in Molecular Biology, 137–62. New York, NY: Springer US, 2023. http://dx.doi.org/10.1007/978-1-0716-3577-3_9.

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Perner, Petra. "Detecting the Transition Stage of Cells and Cell Parts by Prototype-Based Classification." In Advances in Data Mining. Applications and Theoretical Aspects, 189–99. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-08976-8_14.

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Abendroth, Martin, Stephan Roth, Alexander Malik, Andreas Seupel, Meinhard Kuna, and Bjoern Kiefer. "Modeling and Evaluation of the Thermo-mechanical Behavior of Filter Materials and Filter Structures." In Multifunctional Ceramic Filter Systems for Metal Melt Filtration, 387–425. Cham: Springer International Publishing, 2024. http://dx.doi.org/10.1007/978-3-031-40930-1_16.

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AbstractTo capture and predict the chemo-thermo-mechanical behavior of ceramic foam filters, material models and simulation tools are required. The description of the thermo-mechanical inelastic behavior as well as the in-situ layer formation on reactive filters have been the aims of this subproject. Challenging aspects in the whole progress are the exact geometrical replication of the underlying foam structure of the filter and the lack of experimental data for many relevant loading cases. The software FoamGUI is developed to generate parametrized, periodic three-dimensional representative volume elements (RVE) of foam structures, which are used in continuum and fluid mechanical simulations as well as for 3D-printing. Calculation concepts are formulated to predict the inelastic deformation and failure behavior of ceramic open-cell foams under thermo-mechanical loading. First-order homogenization approaches are used to conclude from the mesoscopic behavior of the foam RVE to the macroscopic response of filter structures. A hybrid approach is developed in the established framework of rate-independent plasticity in combination with neural networks, which replace the plastic flow potential and the evolution equations of internal state variables. Another modeling aspect is motivated by the experimentally observed growth of an in situ layer during the so-called reactive phase of the filtration process. This phenomenon motivates the development of a model to describe diffusion, chemical reactions and phase transition processes of multi-phase/multi-component systems using the phase-field method. This allows the simulation of spatially and temporally resolved microstructure evolution leading to the layer formation.
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Hutchins, Erica J., and Marianne E. Bronner. "A Spectrum of Cell States During the Epithelial-to-Mesenchymal Transition." In Methods in Molecular Biology, 3–6. New York, NY: Springer US, 2020. http://dx.doi.org/10.1007/978-1-0716-0779-4_1.

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Cerone, Antonio, and Enrico Marsili. "A Formal Model for the Simulation and Analysis of Early Biofilm Formation." In From Data to Models and Back, 134–51. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-70650-0_9.

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AbstractBiofilms are structured communities of bacterial cells adherent to a surface. This bacterial state is called sessile.This paper focuses on the modelling of the transition between planktonic and sessile state using Real-time Maude as the modelling language. With more and more bacteria joining the sessile community, the likelihood of producing a biofilm increases. Once the percentage of bacterial cells that adheres to the surface reaches a threshold, which is specific for the considered bacterium species, a permanent biofilm is formed. An important challenge is to predict the time needed for the formation of a biofilm on a specific surface, in order to plan when the material infrastructure that comprises such a surface needs to be cleaned or replaced. We exploit the model-checking features of Real-time Maude to formally prove that a regular cleaning or replacement of the infrastructure prevents the biofilm formation.
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Strand, Roger, and Dominique Chu. "Crossing the Styx: If Precision Medicine Were to Become Exact Science." In Human Perspectives in Health Sciences and Technology, 133–54. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-92612-0_9.

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AbstractThe term “precision medicine” is used to denote existing practices as well as how medical research and practice are imagined to become in the future. One important element of the imaginaries of precision medicine is the development of systems biology and computational models with the promise of numerical precision and conceptual rigour. If precision medicine were to become an exact science that relies on computational models, it might increase precision in diagnosis and treatment, specifying the right drug to the right patient at the right time. It should be noted, though, that computational models require explicit specification of the properties and boundaries of the system to be modelled, whereas cells, tissues and patients are predominantly open systems in their natural state. Accordingly, such models risk being precisely wrong instead of approximately right. Right and wrong, however, are value judgements that depend upon the aims and scope of the scientific and medical enterprise. In order for medicine to become an exact science, cells, tissues and patients would have to be reconceived and/or reconfigured as relatively closed systems with relatively deterministic behaviour. The realization of precision medicine as an exact science may thus be accompanied by a transition from a world of complex natural life to a world of reduced life or a simple delay of death; a transition to be likened with the crossing of the Styx.
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Chavez-Alvarez, Rocio, Arturo Chavoya, and Cuauhtemoc Lopez-Martin. "Finding the Minimal Gene Regulatory Function in the Presence of Undefined Transitional States Using a Genetic Algorithm." In Information Processign in Cells and Tissues, 238–49. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-28792-3_29.

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Hasse, Anja. "Chapter 7. Stability of inflectional variation." In Studies in Language Companion Series, 202–28. Amsterdam: John Benjamins Publishing Company, 2023. http://dx.doi.org/10.1075/slcs.234.07has.

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Free morphological variation is an understudied phenomenon; however, it is implicitly included in studies on overabundance. In the inflection of the indefinite article in Zurich German, we find overabundance of the dative masculine/neuter cell over a timespan of nearly 200 years. As this study shows, instances of overabundance or (possibly) free variation have to be analysed in great detail. In Zurich German, we see a complex picture of free variation in certain linguistic contexts and conditioned variation in other contexts. This instance of morphological variation in Zurich German is quite stable, which contradicts the hypothesis that morphological variation is always a transitional stage of a changing inflectional system, and it even exists at the intra-individual level.
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Su, Hai-Ching, Ken-Tsung Wong, and Chung-Chih Wu. "Solid-State Light-Emitting Electrochemical Cells Based on Cationic Transition Metal Complexes for White Light Generation." In WOLEDs and Organic Photovoltaics, 105–35. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-14935-1_4.

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Conference papers on the topic "Cell state transition"

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Farahat, Waleed A., and H. Harry Asada. "Identification of Phenotypic State Transition Probabilities in Living Cells." In ASME 2009 Dynamic Systems and Control Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/dscc2009-2705.

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Living cells stochastically switch their phenotypic states in response to environmental cues to maintain persistence and viability. Estimating the state transition probabilities from biological observations of cell populations gives valuable insight to the underlying processes, and gives insights as to how the transition statistics are influenced by external factors. In this work, we present two Bayesian estimation approaches. The first is applicable when individual cell state trajectories are observed. The second approach is applicable when only aggregate population statistics are available. Estimation of transition probabilities when individual cell state trajectories are available is a straightforward problem, whereas estimation from only aggregate statistics can be computationally expensive. In the latter case, we present an algorithm that relies on three key ideas to cut down computational time: i) approximating high-dimensional multinomial distributions with multi-variate Gaussians, ii) employing Monte-Carlo techniques to efficiently integrate over high dimensional spaces, and iii) explicitly incorporating sampling constraints by computing lower dimensional distributions over the constrained variable. Simulation results demonstrate the viability of the algorithm.
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Liu, Zuolin, Hongbin Fang, Jian Xu, and K. W. Wang. "Triple-Cell Origami Structure for Multistable Transition Sequences." In ASME 2020 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/detc2020-22354.

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Abstract With the infinite design space and the excellent folding-induced deformability, origami has been recognized as an effective tool for developing reconfigurable structures. Particularly, the multistable origami structure, which possesses more than one stable configuration that is distinct in shape and mechanical properties, has received wide research attention. Generally, the origami structure reaches a kinematic singularity point when switching among different stable configurations. At this critical state, multiple switching sequences are possible, and the actual transition is generally hard to predict. In this paper, evolving from the conventional bistable Miura-ori unit, a triple-cell origami structure with eight potential stable configurations is proposed, which serves as a platform for investigating the transition sequences among different stable configurations. To quantify the overall elastic potential of the structure, besides the conventional elastic energy originating from the rigid folding creases, extra elastic potential induced by the mismatch among the cells are introduced, so that folding of the triple-cell structure is no longer a strict single degree-of-freedom mechanism. Instead, the three cells can deform asynchronously to avoid reaching the kinematic singularity point. Hence, under displacement loading, the transition sequence of the multistable structure is predicted by performing optimization on the elastic potential energy. It shows that sequences with multifarious characteristics are possible, including reversible and irreversible transitions, and transitions with symmetric and asymmetric energy barriers. Considering that the fundamental transition mechanisms are of great significance in understanding the quasi-static and dynamic behaviors of multistable structures, the results could be potentially employed for developing morphing structures, adaptive metamaterials, and mechanical logic gates.
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Alsayegh, Osamah A., and Fotouh A. Al-Ragom. "An Energy Transition Scenario for the State of Kuwait." In ASME 2015 9th International Conference on Energy Sustainability collocated with the ASME 2015 Power Conference, the ASME 2015 13th International Conference on Fuel Cell Science, Engineering and Technology, and the ASME 2015 Nuclear Forum. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/es2015-49069.

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With population of 3.9 million and area of 17,818 km2, the State of Kuwait holds about 8% and 1% of the world proven oil and gas reserves, respectively. Its total primary energy (oil and gas) production is about 3.5 million barrel oil equivalent per day (Mboe/d). Yet, Kuwait is facing energy challenges as a result of high and rapid growth of domestic energy consumption that has reached 18% of its total primary energy production. Therefore, adopting policies to transform the present energy system to a sustainable system has become indispensable national requirement. In this paper, a transition scenario for Kuwait’s energy system is proposed. The transition scenario addresses both the supply and demand sides through diversifying primary energy mix and energy demand management measures. The energy mix scenario is the optimum outcome of MARKAL-TIMES model of the energy system of Kuwait. Modeling results show that meeting 10% of the country’s energy demand through the exploitation of solar and wind energies by 2030 is the technical and economical optimal scenario. While the demand management measures are based on pilot energy conservation and efficiency study that shows energy saving could reach 24% and leading to savings of 4% reduction in power installation capacity. Utilization of efficient water desalination systems can reduce national energy consumption by 5%. The paper concludes with policy implications that are essential to launch the transformation toward sustainability.
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Weinberg, Eli J., and Mohammad R. K. Mofrad. "Multiscale Simulations of the Healthy and Calcific Human Aortic Valve." In ASME 2008 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2008. http://dx.doi.org/10.1115/sbc2008-192671.

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In the heart’s aortic valve, maintenance of a healthy state and transition to disease states are modulated by the cells in the valve. The cells found within the valve leaflets are valvular interstitial cells (VICs) and those found on the fluid-facing surfaces are endothelial cells (ECs). Both types of cell are known to respond to their mechanical state; that is, the stresses and deformations imposed on a cell by its surrounding environment. Here we present a set of simulations to examine these mechanical states of the cells as the valve goes through its opening and closing cycle. We have created models at each of the cell, tissue, and organ length scales and introduced a system of reference configurations to link the scales. Each simulation and the set of multiscale simulation are verified against experimental data. This multiscale simulation approach allows us to accurately predict the dynamic, three-dimensional mechanical state of cells throughout the valve.
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Weinberg, Eli, and Mohammad Mofrad. "Multiscale Fluid-Structure Simulations of the Aortic Valve." In ASME 2007 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2007. http://dx.doi.org/10.1115/sbc2007-176730.

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In the heart aortic valve, maintenance of healthy conditions and transition to diseased conditions are modulated by the cells in the valve. The cells found within the valve leaflets and walls are the valvular interstitial cells (VICs), and those found on the fluid-facing surfaces are the endothelial cells (ECs). Both types of cell are known to respond to their mechanical state; that is, the stresses and deformations imposed on the cell by its surrounding environment. Here, we present a set of simulations to examine the mechanical states of cells as the valve goes through its opening and closing cycle. The simulations span the cell, tissue, and organ length scales. Taken together, these simulations predict the dynamic, three-dimensional mechanical state of VICs and ECs throughout the valve.
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Norte Pinto, Nuno, António Pais Antunes, and Josep Roca Cladera. "The incorporation of accessibility in land use transition potential for cellular automata models." In International Conference Virtual City and Territory. Mexicali: Universidad Autónoma de Baja California, 2010. http://dx.doi.org/10.5821/ctv.7618.

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Cellular automata (CA) models are used for simulating land use change for more than two decades. These models have a simple structure based on a cellular partition of space, considering a finite set of cell states (or land uses) and their interaction within a given neighborhood area, changing throughout time under a set of transition rules. Transition rules are based on more or less sophisticated measures of state transition: they can be more complex rules that try to incorporate the different drivers of land use change or they can be purely probabilistic rules that take into account only the states of neighboring cells. This last approach is often based on a measure of a transition potential that establishes a rank for state transition for every cell. There are many drivers of land use change and accessibility is acknowledged as being one of the most important ones. At the same time, transportation systems (thus accessibility) are also influenced by land use change. This suggests that CA models are potentially good tools to simulate these phenomena by considering the cross-interdependences between both. In this presentation, we make a reflection on how accessibility can be measured, incorporated, and used to improve CA transition rules based on transition potentials towards more representative models of land use change. We address not only modeling requirements but also the potential of using CA models to evaluate both the impacts of transportation policies in land use change, and vice versa.
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Nagel, Thomas, and Daniel J. Kelly. "Compaction and Anisotropy Induced by Remodeling of the Collagen Network’s State of Tension-Compression Transition." In ASME 2011 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2011. http://dx.doi.org/10.1115/sbc2011-53399.

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Extracellular matrix remodeling is ubiquitous in connective, musculoskeletal and cardiovascular tissues. The collagen network can thereby not only remodel its orientation [1] but also its stress-free configuration. This stress-free configuration can be described by the so-called transition stretch — the stretch above which a fiber begins to bear load. Remodeling of collagen crimp has been shown to be involved in long bone growth [2], contracture, scar pathologies, collagen gel compaction and can be cell mediated or occur via cell-independent mechanisms [3, 4, 5].
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Luo, Ming, Michael Brooks, Joseph Burnett, Nathan Truchan, Duxin Sun, and Max S. Wicha. "Abstract LB-053: Tracing redox-regulated breast cancer stem cell state transition using a dual fluorescent reporter system." In Proceedings: AACR Annual Meeting 2018; April 14-18, 2018; Chicago, IL. American Association for Cancer Research, 2018. http://dx.doi.org/10.1158/1538-7445.am2018-lb-053.

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Small, Evan, Sadegh M. Sadeghipour, and Mehdi Asheghi. "Numerical Modeling of Heat Transfer and Phase Transition in Programming the Ovonic Unified Memory Cells." In ASME 2005 Pacific Rim Technical Conference and Exhibition on Integration and Packaging of MEMS, NEMS, and Electronic Systems collocated with the ASME 2005 Heat Transfer Summer Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/ipack2005-73188.

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An Ovonic Unified Memory (OUM) cell is a semiconductor device that stores data by a thermally induced phase transition between polycrystalline (set) and amorphous (reset) states in a thin film of chalcogenide alloy. The small volume of active media acts as a programmable resistor switching between a high (amorphous) and low (crystalline) resistance state. The change in the film resistivity (>40X dynamic range) caused by this rapid, reversible structural change is measured to detect the state of the cell (set or reset) for read out. OUM can benefit from a simulator capable of predicting the electrical, thermal, and crystallization behavior for design and optimization, particularly at the present stage of the development. This paper reports on the efforts being made to prepare such a numerical simulator, using an existing finite element computer code as the source for thermal and electrical modeling, and a custom crystallization code for phase prediction. Heat generation in the device is by Joule heating and is achieved by passage of the electric current, which is obtained from the electrical simulation. This result appears in the heat source term of the heat transfer equation that is solved for thermal modeling. As the first attempt the Ohmic current-voltage relation was implemented successfully to simulate set and reset in a two dimensional model of OUM. Solution of the drift-diffusion equation is now underway to capture the semiconductor behavior of the I-V curve. A good progress is made however, still more works needs to be done to fully implement the drift diffusion equation.
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Huang, Ruby YJ, Meng Kang Wong, Vin Yee Chung, Aloysius Ng, You Fei Lee, Elke Pietschmann, Seiichi Mori, Noriomi Matsumura, and Jean Paul Thiery. "Abstract 3437: Epithelial-mesenchymal transition spectrum characterized by an ovarian cancer cell line library defines an aggressive metastable state." In Proceedings: AACR 102nd Annual Meeting 2011‐‐ Apr 2‐6, 2011; Orlando, FL. American Association for Cancer Research, 2011. http://dx.doi.org/10.1158/1538-7445.am2011-3437.

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Reports on the topic "Cell state transition"

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Splitter, Gary A., Menachem Banai, and Jerome S. Harms. Brucella second messenger coordinates stages of infection. United States Department of Agriculture, January 2011. http://dx.doi.org/10.32747/2011.7699864.bard.

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Aim 1: To determine levels of this second messenger in: a) B. melitensiscyclic-dimericguanosinemonophosphate-regulating mutants (BMEI1448, BMEI1453, and BMEI1520), and b) B. melitensis16M (wild type) and mutant infections of macrophages and immune competent mice. (US lab primary) Aim 2: To determine proteomic differences between Brucelladeletion mutants BMEI1453 (high cyclic-dimericguanosinemonophosphate, chronic persistent state) and BMEI1520 (low cyclicdimericguanosinemonophosphate, acute virulent state) compared to wild type B. melitensisto identify the role of this second messenger in establishing the two polar states of brucellosis. (US lab primary with synergistic assistance from the Israel lab Aim 3: Determine the level of Brucellacyclic-dimericguanosinemonophosphate and transcriptional expression from naturally infected placenta. (Israel lab primary with synergistic assistance from the US lab). B. Background Brucellaspecies are Gram-negative, facultative intracellular bacterial pathogens that cause brucellosis, the most prevalent zoonosis worldwide. Brucellosis is characterized by increased abortion, weak offspring, and decreased milk production in animals. Humans are infected with Brucellaby consuming contaminated milk products or via inhalation of aerosolized bacteria from occupational hazards. Chronic human infections can result in complications such as liver damage, orchitis, endocarditis, and arthritis. Brucellaspp. have the ability to infect both professional and non-professional phagocytes. Because of this, Brucellaencounter varied environments both throughout the body and within a cell and must adapt accordingly. To date, few virulence factors have been identified in B. melitensisand even less is known about how these virulence factors are regulated. Subsequently, little is known about how Brucellaadapt to its rapidly changing environments, and how it alternates between acute and chronic virulence. Our studies suggest that decreased concentrations of cyclic dimericguanosinemonophosphate (c-di-GMP) lead to an acute virulent state and increased concentrations of c-di-GMP lead to persistent, chronic state of B. melitensisin a mouse model of infection. We hypothesize that B. melitensisuses c-di-GMP to transition from the chronic state of an infected host to the acute, virulent stage of infection in the placenta where the bacteria prepare to infect a new host. Studies on environmental pathogens such as Vibrio choleraeand Pseudomonas aeruginosasupport a mechanism where changes in c-di-GMP levels cause the bacterium to alternate between virulent and chronic states. Little work exists on understanding the role of c-di-GMP in dangerous intracellular pathogens, like Brucellathat is a frequent pathogen in Israeli domestic animals and U.S. elk and bison. Brucellamust carefully regulate virulence factors during infection of a host to ensure proper expression at appropriate times in response to host cues. Recently, the novel secondary signaling molecule c-di-GMP has been identified as a major component of bacterial regulation and we have identified c-di-GMP as an important signaling factor in B. melitensishost adaptation. C. Major conclusions, solutions, achievements 1. The B. melitensis1453 deletion mutant has increased c-di-GMP, while the 1520 deletion mutant has decreased c-di-GMP. 2. Both mutants grow similarly in in vitro cultures; however, the 1453 mutant has a microcolony phenotype both in vitro and in vivo 3. The 1453 mutant has increased crystal violet staining suggesting biofilm formation. 4. Scanning electron microscopy revealed an abnormal coccus appearance with in increased cell area. 5. Proteomic analysis revealed the 1453 mutant possessed increased production of proteins involved in cell wall processes, cell division, and the Type IV secretion system, and a decrease in proteins involved in amino acid transport/metabolism, carbohydrate metabolism, fatty acid production, and iron acquisition suggesting less preparedness for intracellular survival. 6. RNAseq analysis of bone marrow derived macrophages infected with the mutants revealed the host immune response is greatly reduced with the 1453 mutant infection. These findings support that microlocalization of proteins involved in c-di-GMP homeostasis serve a second messenger to B. melitensisregulating functions of the bacteria during infection of the host.
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Matera, Carola, Magaly Lavadenz, and Elvira Armas. Dialogic Reading and the Development of Transitional Kindergarten Teachers’ Expertise with Dual Language Learners. CEEL, 2013. http://dx.doi.org/10.15365/ceel.article.2013.2.

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This article presents highlights of professional development efforts for teachers in Transitional Kindergarten (TK) classrooms occurring throughout the state and through a collaborative effort by researchers from the Center for Equity for English Learners (CEEL) at Loyola Marymount University. The article begins by identifying the various statewide efforts for professional development for TK teachers, followed by a brief review of the literature on early literacy development for diverse learners. It ends with a description of a partnership between CEEL and the Los Angeles Unified School District to provide professional development both in person and online to TK teachers on implementing Dialogic Reading practices and highlights a few of the participating teachers. This article has implications for expanding the reach of professional development for TK teachers through innovative online modules.
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Matera, Carola. Incorporating Scaffolded Dialogic Reading Practice in Teacher Training: An Opportunity to Improve Instruction for Young Dual Language Learners in Transitional Kindergarten. Loyola Marymount University, 2015. http://dx.doi.org/10.15365/ceel.policy.4.

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Findings from a joint collaborative between the Center for Equity for English Learners (CEEL) at Loyola Marymount University and the Los Angeles Unified School District (LAUSD) to provide professional development and coaching to Transitional Kindergarten (TK) teachers on the Scaffolded Dialogic Reading (SDR) are presented in this policy brief. SDR is a method to enhance language skills through dialogue and research-based scaffolds between teachers and small groups of children mediated through repeated readings of storybooks. The purpose of this brief is to: 1) state the opportunity to ensure Dual Language Learner (DLL) support within California’s TK policy; 2) provide a synthesis of research findings; and 3) provide TK professional learning and policy recommendations that would allow for the inclusion of professional development on evidence-based practices purposefully integrated with DLL supports. Policy recommendations include: 1) utilize professional learning modules such as SDR in 24 ECE unit requirement for TK teachers; 2) include individuals with ECE and DLL expertise in the ECE Teacher Preparation Advisory Panel; and 3) allocate additional funds in the state budget for training on SDR, in-classroom support for TK teachers of DLLs, and evaluation of these efforts.
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Ruiz, Pablo, Craig Perry, Alejando Garcia, Magali Guichardot, Michael Foguer, Joseph Ingram, Michelle Prats, Carlos Pulido, Robert Shamblin, and Kevin Whelan. The Everglades National Park and Big Cypress National Preserve vegetation mapping project: Interim report—Northwest Coastal Everglades (Region 4), Everglades National Park (revised with costs). National Park Service, November 2020. http://dx.doi.org/10.36967/nrr-2279586.

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The Everglades National Park and Big Cypress National Preserve vegetation mapping project is part of the Comprehensive Everglades Restoration Plan (CERP). It is a cooperative effort between the South Florida Water Management District (SFWMD), the United States Army Corps of Engineers (USACE), and the National Park Service’s (NPS) Vegetation Mapping Inventory Program (VMI). The goal of this project is to produce a spatially and thematically accurate vegetation map of Everglades National Park and Big Cypress National Preserve prior to the completion of restoration efforts associated with CERP. This spatial product will serve as a record of baseline vegetation conditions for the purpose of: (1) documenting changes to the spatial extent, pattern, and proportion of plant communities within these two federally-managed units as they respond to hydrologic modifications resulting from the implementation of the CERP; and (2) providing vegetation and land-cover information to NPS park managers and scientists for use in park management, resource management, research, and monitoring. This mapping project covers an area of approximately 7,400 square kilometers (1.84 million acres [ac]) and consists of seven mapping regions: four regions in Everglades National Park, Regions 1–4, and three in Big Cypress National Preserve, Regions 5–7. The report focuses on the mapping effort associated with the Northwest Coastal Everglades (NWCE), Region 4 , in Everglades National Park. The NWCE encompasses a total area of 1,278 square kilometers (493.7 square miles [sq mi], or 315,955 ac) and is geographically located to the south of Big Cypress National Preserve, west of Shark River Slough (Region 1), and north of the Southwest Coastal Everglades (Region 3). Photo-interpretation was performed by superimposing a 50 × 50-meter (164 × 164-feet [ft] or 0.25 hectare [0.61 ac]) grid cell vector matrix over stereoscopic, 30 centimeters (11.8 inches) spatial resolution, color-infrared aerial imagery on a digital photogrammetric workstation. Photo-interpreters identified the dominant community in each cell by applying majority-rule algorithms, recognizing community-specific spectral signatures, and referencing an extensive ground-truth database. The dominant vegetation community within each grid cell was classified using a hierarchical classification system developed specifically for this project. Additionally, photo-interpreters categorized the absolute cover of cattail (Typha sp.) and any invasive species detected as either: Sparse (10–49%), Dominant (50–89%), or Monotypic (90–100%). A total of 178 thematic classes were used to map the NWCE. The most common vegetation classes are Mixed Mangrove Forest-Mixed and Transitional Bayhead Shrubland. These two communities accounted for about 10%, each, of the mapping area. Other notable classes include Short Sawgrass Marsh-Dense (8.1% of the map area), Mixed Graminoid Freshwater Marsh (4.7% of the map area), and Black Mangrove Forest (4.5% of the map area). The NWCE vegetation map has a thematic class accuracy of 88.4% with a lower 90th Percentile Confidence Interval of 84.5%.
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