Search results for "Dynamic"

Strongly Coupled Coherent Phonons in Single-Layer MoS 2

2019

We present a transient absorption setup combining broadband detection over the visible-UV range with high temporal resolution ($\sim$20fs) which is ideally suited to trigger and detect vibrational coherences in different classes of materials. We generate and detect coherent phonons (CPs) in single layer (1L) MoS$_2$, as a representative semiconducting 1L-transition metal dichalcogenide (TMD), where the confined dynamical interaction between excitons and phonons is unexplored. The coherent oscillatory motion of the out-of-plane $A'_{1}$ phonons, triggered by the ultrashort laser pulses, dynamically modulates the excitonic resonances on a timescale of few tens fs. We observe an enhancement by…

Questing abundance of adult taiga ticks Ixodes persulcatus and their Borrelia prevalence at the north-western part of their distribution

2020

Background Because ixodid ticks are vectors of zoonotic pathogens, including Borrelia, information of their abundance, seasonal variation in questing behaviour and pathogen prevalence is important for human health. As ticks are invading new areas northwards, information from these new areas are needed. Taiga tick (Ixodes persulcatus) populations have been recently found at Bothnian Bay, Finland. We assessed seasonal variation in questing abundance of ticks and their pathogen prevalence in coastal deciduous forests near the city of Oulu (latitudes 64–65°) in 2019. Methods We sampled ticks from May until September by cloth dragging 100 meters once a month at eight study sites. We calculated a…

The crater lake of Ilamatepec (Santa Ana) volcano, El Salvador: insights into lake gas composition and implications for monitoring

2019

We here present the first chemical characterization of the volcanic gas plume issuing from the Santa Ana crater lake, a hyper-acidic crater lake (pH of − 0.2 to 2.5) in north-western El Salvador. Our results, obtained during regular surveys in 2017 and 2018 using a Multi-GAS instrument, demonstrate a hydrous gas composition (H2O/SO2 ratios from 32 to 205) and SO2 as the main sulfur species (H2S/SO2 = 0.03–0.1). We also find that gas composition evolved during our investigated period, with the CO2/SO2 ratio decreasing by one order of magnitude from March 2017 (37.2 ± 9.7) to November 2018 (< 3). This compositional evolution toward more magmatic (SO2-rich) compositions is interpreted in the c…

Evaluating fundamental life-history traits for Tobacco etch potyvirus

2013

Los virus de ARN son probablemente algunos de los parásitos más extendidos que se pueden encontrar en todas las formas de vida. Estos agentes infecciosos parecen particularmente propensos a causar enfermedades emergentes en plantas, seres humanos y otros animales. Sus habilidades para escapar al sistema inmune, evadir estrategias antivirales o para infectar a nuevas especies son una consecuencia directa de su enorme capacidad para evolucionar rápidamente. Comprender los procesos básicos del cambio evolutivo puede ser unos de los principales pasos necesarios en el diseño de nuevas estrategias de intervención. Desde una perspectiva evolutiva, una de las principales características de los viru…

Mentalizing in Organizations: A Psychodynamic Model for an Understanding of Well-Being and Suffering in the Work Contexts

2017

Moving from the paradigms of “mentalization” and “reflective function” (Fonagy and colleagues), this article develops the concept of “mentalizing” in organizations, understood as a process of construction of shared meaning in the work contexts, and whose absence or deterioration produces suffering in organizational experience, exposing individuals to significant psychosocial risks. This model converges in outlining a framework in which the absence of a reflective competence and the lack of symbolization of the experience of work fall on the perception of one's own job, and on the relationship with colleagues and management, producing unsustainability of the work experience. The availability…

Understanding Structure and Stability of Monoclinic Zirconia Surfaces from First-Principles Calculations

2017

Under the water-rich pre-treatment and/or reaction conditions, structure and chemistry of the monoclinic zirconia surfaces are strongly influenced by oxygen vacancies and incorporated water. Here, we report a combined first-principles and atomistic thermodynamics study on the structure and stability of selected surfaces of the monoclinic zirconia. Our results indicate that among the studied surfaces, the most stable (111) surface is the least vulnerable towards oxygen vacancies in contrast to the less stable (011) and (101) surfaces, where formation of oxygen vacancies is energetically more favorable. Furthermore, we present a vigorous, systematic screening of water incorporation onto the s…

Animated and interactive cartography to improve the understanding of the regional dynamics

2013

International audience

Growth and regional convergence : evidence from the Finnish provinces and subregions, 1960 to 1994

1997

Regional Economic Integration in the Southern African Development Community (SADC): Analysing the Dynamics and Performance

2020

This article analyses the dynamics and performance of regional economic integration in the Southern African Development Community (SADC). It proposes an innovative theoretical approach to the analysis of regionalism that refers to cooperation theory and takes the impact of external actors explicitly into account. The motivation for this research stems from the observation of a new wave of regionalism in the Global South. Many of these new or reformed regional integration organisations (RIOs) comprise of developing countries, particularly in Africa. In contrast to expectations of most mainstream integration theories, new regionalisms in the Southern Hemisphere have come into existence and sh…

Acoustic wave guides as infinite-dimensional dynamical systems

2015

We prove the unique solvability, passivity/conservativity and some regularity results of two mathematical models for acoustic wave propagation in curved, variable diameter tubular structures of finite length. The first of the models is the generalised Webster's model that includes dissipation and curvature of the 1D waveguide. The second model is the scattering passive, boundary controlled wave equation on 3D waveguides. The two models are treated in an unified fashion so that the results on the wave equation reduce to the corresponding results of approximating Webster's model at the limit of vanishing waveguide intersection.