Turbulence in the Watchmaking Field: A Socioecological Approach to Strategizing

The Swiss Watchmaking Field is again entering a period of turbulence (Emery and Trist 1965) due to regulatory changes, the emergence of connected devices, volatile consumer behavior, currency changes, and relations among these factors that may challenge the capabilities for adaptation of key firms. Ramirez and Selsky (2014) suggested that in turbulent environments, a socio-ecological strategy approach emphasizing collaboration at a field level rather than competition is advisable. Based on multiple case study research, we empirically examine the application of contrasting strategic stances and principles comparing competitive strategy with the socio-ecological approach. We assess the presence of the transition, heterogeneity and subjectivity principles and how a coopetition strategic stance fares in the context of the Swiss Watchmaking Industry. We conclude by exploring new research venues

Photoinitiated polymerization of a dental formulation: 1. Influence of photoinitiating system, temperature and luminous intensity

The photoinitiated polymerization of a dental formulation is composed of Mixture of monomers 75%Bis-GMA/25%TEGDMA and CQ/DMAEMA as radical photoinitiator was studied by using isothermal photocalorimetry. The effect of temperature, light intensity and photoinitiating system concentration on reaction was investigated. A maximum conversion was obtained for a photoinitiator system concentration of 1% (w/w) and for the highest light intensity studied. It should be noted that a correlation between the glass transition temperature of the final polymer and the conversion has been studied.Keywords: dental composite; photopolymerization; dimethacrylate resin; photoinitiator syste

Nouveaux systèmes micellaires intelligents à partir d'huile de lin (synthèse, comportements physico-chimiques et encapsulation)

Les micelles apparaissent comme prometteuses dans le domaine de la vectorisation de médicaments. Afin d améliorer leur biocompatibilité nous nous intéressons ici à des synthèses originales de copolymères amphiphiles comportant un bloc hydrophobe lipidique biosourcé. Un polymère intelligent constitue le bloc hydrophile. L huile de lin subit une modification chimique afin d introduire un site amorceur de polymérisation. Le bloc hydrophile est alors ajouté par polymérisation contrôlée. Deux copolymères sont obtenus, le lipide-b-poly(acide acrylique), pH-sensible et le lipide-b-poly(2-isopropyl-oxazoline), thermo-sensible. Une caractérisation physico-chimique complète révèle des concentrations micellaires critiques basses et des micelles de 10 nm. Un système mixte est préparé par mélange des deux copolymères. L étude de ce système prouve une sensibilité aux deux stimuli. Afin d améliorer la stabilité des micelles, nous proposons la photo-réticulation des insaturations de la chaîne lipidique.Small micellar systems seem to be really promising candidates for drug delivery applications. In order to improve the bio-assimilation of our system, the original synthesis of amphiphilic copolymers from linseed oil is carried out. First, linseed oil is chemically modified in order to introduce a polymerization initiating site. Then, the lipoinitiator is engaged in the controlled polymerization of the hydrophilic block. Two amphiphilic copolymers are obtained through this strategy: a pH-sensitive lipid-b-poly(acrylic acid), and a thermo-sensitive lipid-b-poly(2-isopropyl-oxazoline). Both present a low critical micellar concentration and form small micelles (~10 nm). By mixing both copolymers, mixed micelles responding to both stimuli were obtained. In order to improve the system s stability, the photo-cross-linking of the lipidic double bonds in the micelle s core is finally realized.ROUEN-INSA Madrillet (765752301) / SudocSudocFranceF

Sub-micron diameter micropillar cavities with high Quality factors and ultra-small mode volumes

We theoretically demonstrate high Quality factor micropillar cavities with record low mode volumes based on the TiO2/SiO2 material system. The proposed cavities have Q/V three orders of magnitude larger than previously reported ones. We show that our cavity embedded with diamond nanocrystal provides a feasible platform for cavity quantum electrodynamics experiments in the strong coupling limit.Comment: 10 pages, 3 figure

Widely tunable, efficient on-chip single photon sources at telecommunication wavelengths

We demonstrate tunable on-chip single photon sources using the Stark tuning of single quantum dot (QD) excitonic transitions in short photonic crystal waveguides (PhC WGs). The emission of single QDs can be tuned in real-time by 9 nm with an applied bias voltage less than 2V. Due to a reshaped density of optical modes in the PhC WG, a large coupling efficiency \beta>65% to the waveguide mode is maintained across a wavelength range of 5 nm. When the QD is resonant with the Fabry-Perot mode of the PhC WG, a strong enhancement of spontaneous emission is observed leading to a maximum coupling efficiency \beta=88%. These results represent an important step towards the scalable integration of single photon sources in quantum photonic integrated circuits.Comment: 15 pages, 5 figue

Mode expansions in the quantum electrodynamics of photonic media with disorder

We address two issues in the quantum electrodynamical description of photonic media with some disorder, neglecting material dispersion. When choosing a gauge in which the static potential vanishes, the normal modes of the medium with disorder satisfy another transversality condition than the modes of the ideal medium. Our first result is an integral equation for optical modes such that all perturbation-theory solutions automatically satisfy the desired transversality condition. Secondly, when expanding the vector potential for the medium with disorder in terms of the normal modes of the ideal structure, we find the gauge transformation that makes the static potential zero, thereby generalizing work by Glauber and Lewenstein [Phys. Rev. A 43, 467 (1991)]. Our results are relevant for the quantum optics of disordered photonic crystals.Comment: 7 pages; accepted in Photonics and Nanostructure

Interfacial Profile and Propagation of Frontal Photopolymerization Waves

We investigate the frontal photopolymerization of a thiol–ene system with a combination of experiments and modeling, focusing on the interfacial conversion profile and its planar wave propagation. We spatially resolve the solid-to-liquid front by FT-IR and AFM mechanical measurements, supplemented by differential scanning calorimetry. A simple coarse-grained model is found to describe remarkably well the frontal kinetics and the sigmoidal interface, capturing the effects of UV light exposure time (or dose) and temperature, as well as the front position and resulting patterned dimensions after development. Analytical solutions for the conversion profile enable the description of all conditions with a single master curve in the moving frame of the front position. Building on this understanding, we demonstrate the design and fabrication of gradient polymer materials, with tunable properties <i>along</i> the direction of illumination, which can be coupled with lateral patterning by modulated illumination or grayscale lithography

Lower bound for the spatial extent of localized modes in photonic-crystal waveguides with small random imperfections

Light localization due to random imperfections in periodic media is paramount in photonics research. The group index is known to be a key parameter for localization near photonic band edges, since small group velocities reinforce light interaction with imperfections. Here, we show that the size of the smallest localized mode that is formed at the band edge of a one-dimensional periodic medium is driven instead by the effective photon mass, i.e. the flatness of the dispersion curve. Our theoretical prediction is supported by numerical simulations, which reveal that photonic-crystal waveguides can exhibit surprisingly small localized modes, much smaller than those observed in Bragg stacks thanks to their larger effective photon mass. This possibility is demonstrated experimentally with a photonic-crystal waveguide fabricated without any intentional disorder, for which near-field measurements allow us to distinctly observe a wavelength-scale localized mode despite the smallness (∼1/1000 of a wavelength) of the fabrication imperfections

Exploring planets and asteroids with 6DoF sensors: Utopia and realism

A 6 degrees-of-freedom (6DoF) sensor, measuring three components of translational acceleration and three components of rotation rate, provides the full history of motion it is exposed to. In Earth sciences 6DoF sensors have shown great potential in exploring the interior of our planet and its seismic sources. In space sciences, apart from navigation, 6DoF sensors are, up to now, only rarely used to answer scientific questions. As a first step of establishing 6DoF motion sensing deeper into space sciences, this article describes novel scientific approaches based on 6DoF motion sensing with substantial potential for constraining the interior structure of planetary objects and asteroids. Therefore we estimate 6DoF-signal levels that originate from lander–surface interactions during landing and touchdown, from a body’s rotational dynamics as well as from seismic ground motions. We discuss these signals for an exemplary set of target bodies including Dimorphos, Phobos, Europa, the Earth’s Moon and Mars and compare those to self-noise levels of state-of-the-art sensors