Dynamics of photoexcited states in weakly coupled cells with two-level systems

AbstractThe coherent nonlinear process where a single photon simultaneously excites two or more two-level systems (qubits) in a single-mode resonator has recently been theoretically predicted. Here we explore the case where the two qubits are placed in different resonators in an array of two or three weakly coupled resonators. Investigating different setups and excitation schemes, we show that this process can still occur with a probability approaching one under specific conditions. The obtained results provide interesting insights into subtle causality issues underlying the simultaneous excitation processes of qubits placed in different resonators.

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Coupling pattern of S1 and S2 amacrine cells in the rabbit retina

Visual Neuroscience ◽

10.1017/s0952523802191115 ◽

2002 ◽

Vol 19 (2) ◽

pp. 119-131 ◽

Cited By ~ 17

Author(s):

WEI LI ◽

JIAN ZHANG ◽

STEPHEN C. MASSEY

Keyword(s):

Amacrine Cells ◽

Cell Types ◽

Wide Field ◽

Rabbit Retina ◽

Main Cell ◽

Weakly Coupled ◽

Coupled Cells ◽

The Matrix ◽

Coupling Pattern ◽

And Cluster Analysis

Previous studies have shown that indoleamine-accumulating cells (IACs) in the rabbit retina consist of two main cell types: S1 and S2 amacrine cells (Vaney, 1986; Sandell & Masland, 1986). Both cell types are wide-field GABA amacrine cells that make reciprocal synaptic contacts with rod bipolar cell terminals (Ehinger & Holmgren, 1979; Strettoi et al., 1990). We have examined the coupling pattern of S1 and S2 amacrine cells after the intracellular injection of Neurobiotin. Our results may be summarized as follows: (1) S1 amacrine cells were extensively coupled and their dendrites formed a network similar to but less dense than the matrix stained with an antibody to serotonin. (2) Morphological observations and cluster analysis, based on a scattergram, showed that the vast majority of coupled cells were S1 amacrine cells, accounting for approximately half of the total IACs. The rest of the uncoupled IACs were S2 amacrine cells. (3) Sometimes, two adjacent varicosities, one from an injected S1 and one from a coupled S1, contacted a single rod bipolar terminal. (4) S2 amacrine cells were also coupled but much less than the S1s. (5) Rarely, crossover coupling between S1 and S2 amacrine cells was observed. These results suggest that the extensive coupling between S1 amacrine cells, combined with a larger dendritic field, may contribute a wide-field component to the inhibitory surround of the rod pathway. By comparison, the smaller, weakly coupled S2 amacrine cells may provide a local component.

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Behavior of ectopic surface: effects of β-adrenergic stimulation and uncoupling

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00381.2003 ◽

2003 ◽

Vol 285 (6) ◽

pp. H2531-H2542 ◽

Cited By ~ 16

Author(s):

Ara Arutunyan ◽

Alain Pumir ◽

Valentin Krinsky ◽

Luther Swift ◽

Narine Sarvazyan

Keyword(s):

Cardiac Cells ◽

Transient Condition ◽

Ectopic Activity ◽

Adrenergic Stimulation ◽

Experimental Conditions ◽

Control Zone ◽

Dynamic Events ◽

Sequence Of Events ◽

Weakly Coupled ◽

Coupled Cells

By using both experimental and theoretical means, we have addressed the progression of ectopic activity from individual cardiac cells to a multicellular two-dimensional network. Experimental conditions that favor ectopic activity have been created by local perfusion of a small area of cardiomyocyte network (I-zone) with an isoproterenol-heptanol containing solution. The application of this solution initially slowed down and then fully blocked wave propagation inside the I-zone. After a brief lag period, ectopically active cells appeared in the I-zone, followed by evolution of the ectopic clusters into slowly propagating waves. The changing pattern of colliding and expanding ectopic waves confined to the I-zone persisted for as long as the isoproterenol-heptanol environment was present. On restoration of the control environment, the ectopic waves from the I-zone broke out into the surrounding network causing arrhythmias. The observed sequence of events was also modeled by FitzHugh-Nagumo equations and included a cell's arrangement of two adjacent square regions of 20 × 20 cells. The control zone consisted of well-connected, excitable cells, and the I-zone was made of weakly coupled cells (heptanol effect), which became spontaneously active as time evolved (isoproterenol effect). The dynamic events in the system have been studied numerically with the use of a finite difference method. Together, our experimental and computational data have revealed that the combination of low coupling, increased excitability, and spatial heterogeneity can lead to the development of ectopic waves confined to the injured network. This transient condition appears to serve as an essential step for the ectopic activity to “mature” before escaping into the surrounding control network.

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DIELECTRIC EVIDENCE FOR EXISTENCE OF TWO-LEVEL-SYSTEMS IN CYCLOHEXANOL, A " GLASSY CRYSTAL " SYSTEM

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19829104 ◽

1982 ◽

Vol 43 (C9) ◽

pp. C9-525-C9-527

Author(s):

G. P. Singh ◽

R. Vacher ◽

R. Calemczuk

Keyword(s):

Crystal System ◽

Two Level Systems

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Photoinhibition in vivo and in vitro Involves Weakly Coupled Chlorophyll–Protein Complexes‡¶

Photochemistry and Photobiology ◽

10.1562/0031-8655(2002)075<0613:pivaiv>2.0.co;2 ◽

2002 ◽

Vol 75 (6) ◽

pp. 613 ◽

Cited By ~ 31

Author(s):

Stefano Santabarbara ◽

Ilaria Cazzalini ◽

Andrea Rivadossi ◽

Flavio M. Garlaschi ◽

Giuseppe Zucchelli ◽

...

Keyword(s):

Protein Complexes ◽

Weakly Coupled ◽

Chlorophyll Protein Complexes ◽

Chlorophyll Protein

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ENTORNO PERSONAL DE APRENDIZAJE BASE, UN SISTEMA DE ACTIVIDADES PARA LA EVALUACIÓN DEL APRENDIZAJE AUTÓNOMO DE IDIOMAS.

REVISTA CIENCIAS PEDAGÓGICAS E INNOVACIÓN ◽

10.26423/rcpi.v4i2.138 ◽

2016 ◽

Vol 4 (2) ◽

Author(s):

Yoan Martínez Márquez ◽

Yalice Gámez Batista ◽

Norberto Valcárcel Izquierdo

Keyword(s):

Learning Styles ◽

Language Learning ◽

Self Regulation ◽

Personal Characteristics ◽

Positive Influence ◽

General Terms ◽

Communication Processes ◽

Weakly Coupled ◽

The One ◽

Meaningful Connections

Las TIC median las interacciones y la comunicación de los estudiantes a diario. Se conciben como mediado-ras de la reflexión y la autorregulación de la actividad del estudiante, resultante de la interacción consciente de la percepción que tiene el estudiante sobre si con la que negocia con el resto de los estudiantes, los ase-sores y la sociedad en general. En este contexto el aprovechamiento de las TIC debe promover una influen-cia formativa en los espacios formales y no formales. Las condicionantes de complementariedad de espa-cios y de unidad en la diversidad de recursos tecnológicos y didácticos deben guiar la actividad que tenga al estudiante como centro de la misma.Ya no se trata de integrar las TIC en el proceso de formación, haciéndolo formal y estandarizado. El reto está en que sean las características personales de los estudiantes, sus estilos de aprendizaje, sus conoci-mientos y experiencias previas, y sus esquemas afectivos los que marquen el aprovechamiento de las TIC en la evaluación del aprendizaje autónomo de inglés.En el presente trabajo se estructura el aprovechamiento de las TIC mediante un EPA base para la evalua-ción del aprendizaje autónomo de inglés. El EPA base constituye un andamiaje de personas, procedimien-tos, espacios de interacción, y de recursos tecnológicos y didácticos. Los componentes que lo conforman se encuentran débilmente acoplados por la tecnología y altamente cohesionados por la significatividad de las conexiones que el estudiante establece entre ellos. Palabras Clave: Aprendizaje, Autonomía, Entorno, Evaluación, Personal. ABSTRACT There is no doubt about the key role of ICT in the interaction and communication processes among students. ICT are thought as a mean for the reflection and self-regulation of students´ activity, which is in a permanent conscientious comparison between the perception a student has about him/herself and the one he/she nego-tiates with the rest of students, advisors and society in general terms. In this context, ICT should promote a positive influence on student formation in formal and non-formal spaces. The conditionals related to spaces combined support and union in the diversity of technological and didactical resources should guide every activity having students at the center of its conception.It is no longer about integrating ICT to the formation process making it formal and standardized. The chal-lenge on autonomous language learning evaluation with ICT has to do with making the differences through personal characteristics of students, their learning styles, previous experiences and affective schemas.In this paper the use of ICT is structured by means of a PLE frame for the evaluation of English autonomous language learning. It is a scaffolding of people, procedures, interaction spaces, and technological and didac-tical resources. Its components are weakly coupled by technologies and highly cohesive by the meaningful connections students establish among them. Keywords: Learning, Autonomy, Evaluation, Environment, Personal. Recibido: septiembre de 2016Aprobado: noviembre de 2016

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Non-Plasmonic SERS with Silicon: Is It Really Safe? New Insights into Opto-Thermics of Core/Shell Microbeads

10.26434/chemrxiv.5813979.v1 ◽

2018 ◽

Author(s):

Nicolò Bontempi ◽

Irene Vassalini ◽

Stefano Danesi ◽

Matteo Ferroni ◽

Paolo Colombi ◽

...

Keyword(s):

Critical Role ◽

Raman Laser ◽

Core Shell ◽

Thermal Coupling ◽

Melting Points ◽

Experimental Proof ◽

Weakly Coupled ◽

Light Management ◽

Laser Sources ◽

First Time

<p>Here we investigate for the first time the opto-thermal behavior of SiO<sub>2</sub>/Si core/shell microbeads (Si-rex) irradiated with three common Raman laser sources (lambda=532, 633, 785 nm) under real working conditions. We obtained an experimental proof of the critical role played by bead size and aggregation in heat and light management, demonstrating that in the case of strong opto-thermal coupling the temperature can exceed that of the melting points of both core and shell components. In addition, we also show that weakly coupled beads can be utilized as stable substrates for plasmon-free SERS experiments.</p>

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