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We present a new description of the known large deviation function of the classical symmetric simple exclusion process by exploiting its connection with the quantum symmetric simple exclusion processes and using tools from free probability. This may seem paradoxal as free probability usually deals with non commutative probability while the simple exclusion process belongs to the realm of classical probability. On the way, we give a new formula for the free energy -- alias the logarithm of the Laplace transform of the probability distribution -- of correlated Bernoulli variables in terms of the set of their cumulants with non-coinciding indices. This latter result is obtained either by developing a combinatorial approach for cumulants of products of random variables or by borrowing techniques from Feynman graphs., 40 pages, submitted to the special issue of the Annales H. Poincare in memory of Krzysztof Gawedzki

We devise a semi-classical model to describe the transport properties of low-dimensional fermionic lattices under the influence of external quantum stochastic noise. These systems behave as quantum stochastic resistors, where the bulk particle transport is diffusive and obeys the Ohm/Fick's law. Here, we extend previous exact studies beyond the one-dimensional limit to ladder geometries and explore different dephasing mechanisms that are relevant to different physical systems, from solid-state to cold atoms. We find a non-trivial dependence of the conductance of these systems on the chemical potential of the reservoirs. We then introduce a semi-classical approach that is in good agreement with the exact numerical solution and provides an intuitive and simpler interpretation of transport in quantum stochastic resistors. Moreover, we find that the conductance of quantum ladders is insensitive to the coherence of the dephasing process along the direction transverse to transport, despite the fact that the system reaches different stationary states. We conclude by discussing the case of dissipative leads affected by dephasing, deriving the conditions for which they effectively behave as Markovian injectors of particles in the system., Comment: 13 pages, 5 figures

Le polymorphisme est l’aptitude des molecules inorganiques et organiques a exister a l’etat solide sous differentes formes cristallines. Ces differentes formes issues d’une meme molecule peuvent presenter des proprietes physiques et chimiques tres eloignees. Cet article aborde tous les aspects de ce phenomene, de l’origine physique aux methodes actuelles d’etude, en passant par le cas particulier des solvates/hydrates.

While battery electric vehicles (EVs) are on the advance, the broad customer basis is still concerned about battery electric range, a phenomenon commonly known as range anxiety. To tackle these concerns, the functionality of in-vehicle navigational systems must adapt to the new propulsion technology with a limited battery capacity. Central aim is to consider charging infrastructure in route planning. Furthermore, detailed powertrain models are required to accurately forecast an EV’s energy consumption. On the other hand, such detailed models are hardly applicable to large scale road networks that are usually handled by routing services for vehicle navigation. This study proposes a two-staged approach to compute time optimal routes for EVs. To this end, a reduced road network is obtained from a leading routing service. Subsequently, a detailed consumption model is applied and the resulting multiobjective shortest path problem is solved using an adapted Moore-Bellman-Ford algorithm. Within an experimental study, the consumption forecast is validated against measurement data and query times of the proposed methodology are assessed for generic routing problems. The former shows significant improvement of consumption forecast accuracy compared to state-of-the-art models while the latter indicates potential for application in car manufacturers vehicle backend services.

Despite the increased interest in battery electric vehicles (BEV), limited range abilities unsettle customers, which is often related to range anxiety. A better understanding of energy consumption and the possibility to accurately predict the remaining battery energy along an upcoming route may help to reduce this stress perception by means of advanced in-vehicle information systems. Addressing the trend towards vehicles with on-board cloud communication and information systems, the present research focuses on electric powertrain consumption and speed profile forecasts. A meaningful prediction of a speed profile for a given route is a basic prerequisite for an accurate consumption forecast. This study proposes a methodology to derive such a speed profile from real-time traffic data obtained from HERE Technologies while considering individual driving style characteristics. Given the predicted speed profile, a detailed BEV consumption model which accounts for BEV specific energy management strategies and environmental factors is used to obtain a consumption forecast. Prediction uncertainties are analyzed and parameter sensitivities with respect to energy consumption are derived as a function of the route dependent mean vehicle speed. Within a field study with Mercedes Benz EQC experimental vehicles, covering thirty-two test cycles, it is shown that the proposed methodology can accurately predict energy consumption for long look-ahead horizons and significantly reduces the variance in prediction compared to a typical baseline strategy.

In this paper a near time-optimal two two-staged flatness based feed-forward controller is developed for the filling process of a hydraulic clutch system within an automatic gearbox. The filling phase significantly affects the shift quality and therefore is a crucial part of gearbox control. Two reduced physical models of the hydraulic actuation system are developed for the two stages of the filling phase. For both models a flat output can be found and the differential parametrization is computed symbolically. Subsequently, a near time optimal trajectory for the flat outputs is generated using an online trajectory generator. A simulation study shows the performance of the controller under different working conditions.

11 pages, to be submitted to Sigma; International audience; We prove an identity in integral geometry, showing that if $P_x$ and $Q_x$ are two polynomials, $\int dx \, \delta(P_x) \otimes \delta(Q_x)$ is proportional to $\delta(R)$ where $R$ is the resultant of $P_x$ and $Q_x$.

For a quantum system in a macroscopically large volume $V$, prepared in a pure state and subject to maximally noisy or ergodic unitary dynamics, the reduced density matrix of any sub-system $v\ll V$ is almost surely totally mixed. We show that the fluctuations around this limiting value, evaluated according to the invariant measure of these unitary flows, are captured by the Gaussian unitary ensemble (GUE) of random matrix theory. An extension of this statement, applicable when the unitary transformations conserve the energy but are maximally noisy or ergodic on any energy shell, allows to decipher the fluctuations around canonical typicality. According to typicality, if the large system is prepared in a generic pure state in a given energy shell, the reduced density matrix of the sub-system is almost surely the canonical Gibbs state of that sub-system. We show that the fluctuations around the Gibbs state are encoded in a deformation of the GUE whose covariance is specified by the Gibbs state. Contact with the eigenstate thermalisation hypothesis (ETH) is discussed., 5 pages + 5 pages Supplementary Material

In this paper a physics-based overall model of a hybrid powertrain equipped with a stepped automatic gearbox is derived. On the one side, the model approach serves as plant model for the development of new control strategies for clutch-to-clutch gear shifts. On the other side, it provides important insight into the dominant dynamic effects. This study focuses on wet clutches and their hydraulic actuation as well as a compact mathematical representation of the planetary gear train. The use of a modified elasto-plastic friction model allows for a physical representation of the friction torque occurring during gear shifts without the need of structural model changes.

We study the dynamics of random walks hopping on homogeneous hyper-cubic lattices and multiplying at a fertile site. In one and two dimensions, the total number $\mathcal{N}(t)$ of walkers grows exponentially at a Malthusian rate depending on the dimensionality and the multiplication rate $��$ at the fertile site. When $d>d_c=2$, the number of walkers may remain finite forever for any $��$; it surely remains finite when $��\leq ��_d$. We determine $��_d$ and show that $\langle\mathcal{N}(t)\rangle$ grows exponentially if $��>��_d$. The distribution of the total number of walkers remains broad when $d\leq 2$, and also when $d>2$ and $��>��_d$. We compute $\langle \mathcal{N}^m\rangle$ explicitly for small $m$, and show how to determine higher moments. In the critical regime, $\langle \mathcal{N}\rangle$ grows as $\sqrt{t}$ for $d=3$, $t/\ln t$ for $d=4$, and $t$ for $d>4$. Higher moments grow anomalously, $\langle \mathcal{N}^m\rangle\sim \langle \mathcal{N}\rangle^{2m-1}$, in the critical regime; the growth is normal, $\langle \mathcal{N}^m\rangle\sim \langle \mathcal{N}\rangle^{m}$, in the exponential phase. The distribution of the number of walkers in the critical regime is asymptotically stationary and universal, viz. it is independent of the spatial dimension. Interactions between walkers may drastically change the behavior. For random walks with exclusion, if $d>2$, there is again a critical multiplication rate, above which $\langle\mathcal{N}(t)\rangle$ grows linearly (not exponentially) in time; when $d\leq d_c=2$, the leading behavior is independent on $��$ and $\langle\mathcal{N}(t)\rangle$ exhibits a sub-linear growth., 23 pages, 6 figures

We consider a model for thermal contact through a diathermal interface between two macroscopic bodies at different temperatures: an Ising spin chain with nearest neighbor interactions is endowed with a Glauber dynamics with different temperatures and kinetic parameters on alternating sites. The inhomogeneity of the kinetic parameter is a novelty with respect to the model of Ref.[1] and we exhibit its influence upon the stationary non equilibrium values of the two-spin correlations at any distance. By mapping to the dynamics of spin domain walls and using free fermion techniques, we determine the scaled generating function for the cumulants of the exchanged heat amounts per unit of time in the long time limit., 20 pages

Motivated by studies of indirect measurements in quantum mechanics, we investigate the effect, in the strong noise limit, of adding an infinitesimal repulsive perturbation to a stochastic differential equation with an attractive fixed point. We conjecture, and prove for an important subclass, that the solutions exhibit a universal behavior when time is rescaled appropriately: by fine-tuning of the time scale with the infinitesimal repulsive perturbation, the trajectories converge in a precise sense to spiky trajectories that can be reconstructed from an auxiliary time-homogeneous Poisson process. Our results are based on two main tools. The first is a time change followed by an application of Skorokhod’s lemma. We prove an effective approximate version of this lemma of independent interest. The second is an analysis of first passage times, which shows a deep interplay between scale functions and invariant measures. We conclude with some speculations of possible applications of the same techniques in other areas.

Researchers in the Powertrain Control Research Laboratory (PCRL) at the University of Wisconsin-Madison have developed single-cylinder engine transient test systems that control the instantaneous dynamic cylinder boundary conditions of these engines to replicate those in the target multi-cylinder engine performance and dynamics. The overall goal is to exploit the benefits of the single-cylinder engine, while eliminating the negative aspects of this device, and to have the single-cylinder “think” it is dynamically operating at any location within a multi-cylinder engine, with the same transient operation. This paper describes the latest developments in controlling the heat transfer geometry and dynamics of the single-cylinder engine to meet these goals. This is a second generation heat transfer simulator (HTS2) that addresses challenges and issues raised from the experimental operation of the original HTS, and that significantly simplifies the control strategies. There is a brief introductory section explaining the overall transient test system and HTS2's role in this system, a presentation of the operational analysis of the heat transfer system, the design and construction of the HTS2, and preliminary performance results.

We propose to use the effect of measurements instead of their number to study the time evolution of quantum systems under monitoring. This time redefinition acts like a microscope which blows up the inner details of seemingly instantaneous transitions like quantum jumps. In the simple example of a continuously monitored qubit coupled to a heat bath, we show that this procedure provides well defined and simple evolution equations in an otherwise singular strong monitoring limit. We show that there exists anomalous observable localised on sharp transitions which can only be resolved with our new effective time. We apply our simplified description to study the competition between information extraction and dissipation in the evolution of the linear entropy. Finally, we show that the evolution of the new time as a function of the real time is closely related to a stable Levy process of index 1/2., 5 pages, 2 figures

La recherche et le developpement pharmaceutiques modernes font largement appel a la physique et a la modelisation mathematique, que ce soit pour la conception de nouvelles entites actives ou le developpement de formes liberant leurs principes actifs de facon programmee ou ciblee. Cet article illustre ce propos a partir de trois exemples d’axes de recherche pharmaceutique : la conception de molecules antithrombotiques, la mise en place d’un controle de qualite de comprimes a liberation prolongee, la conception de medicaments mieux absorbes par l’organisme.

Synaptic plasticity is thought to be a key mechanism of information storage in the CNS. Different forms of synaptic long-term potentiation have been shown to be impaired in neurological disorders. Here, we show that metabotropic glutamate receptor (mGluR)-dependent long-term depression (LTD), but not NMDA receptor-dependent LTD at Schaffer collateral–CA1 synapses, is profoundly impaired after status epilepticus. Brief application of the group I mGluR agonist (R,S)-3,5-dihydroxyphenylglycine (100 μm; 5 min) induced mGluR LTD in control, but not in pilocarpine-treated rats. Experiments in the presence of selective inhibitors of either mGluR5 [2-methyl-6-(phenylethynyl)-pyridine] or mGluR1 [7-(hydroxyimino)cyclopropachromen-carboxylate ethyl ester and (S)-(+)-α-amino-4-carboxy-2-methylbenzeneacetic acid] demonstrate that loss of mGluR LTD is most likely attributable to a loss of mGluR5 function. Quantitative real-time reverse transcription PCR revealed a specific downregulation of mGluR5 mRNA, but not of mGluR1 mRNA in the CA1 region. Furthermore, we detected a strong reduction in mGluR5 protein expression by immunofluorescence and quantitative immunoblotting. Additionally, the scaffolding protein Homer that mediates coupling of mGluR5 to downstream signaling cascades was downregulated. Thus, we conclude that the reduction of mGluR LTD after pilocarpine-induced status epilepticus is the result of the subtype-specific downregulation of mGluR5 and associated downstream signaling components.

A quantum system subjected to a strong continuous monitoring undergoes quantum jumps. This very well known fact hides a neglected subtlety: sharp scale-invariant fluctuations invariably decorate the jump process even in the limit where the measurement rate is very large. This article is devoted to the quantitative study of these remaining fluctuations, which we call spikes, and to a discussion of their physical status. We start by introducing a classical model where the origin of these fluctuations is more intuitive and then jump to the quantum realm where their existence is less intuitive. We compute the exact distribution of the spikes for a continuously monitored qubit. We conclude by discussing their physical and operational relevance., Comment: 8 pages, 8 figures

Small quantum systems can now be continuously monitored experimentally which allows for the reconstruction of quantum trajectories. A peculiar feature of these trajectories is the emergence of jumps between the eigenstates of the observable which is measured. Using the Stochastic Master Equation (SME) formalism for continuous quantum measurements, we show that the density matrix of a system indeed shows a jumpy behavior when it is subjected to a tight measurement (even if the noise in the SME is Gaussian). We are able to compute the jump rates analytically for any system evolution, i.e. any Lindbladian, and we illustrate how our general recipe can be applied to two simple examples. We then discuss the mathematical, foundational and practical applications of our results. The analysis we present is based on a study of the strong noise limit of a class of stochastic differential equations (the SME) and as such the method may be applicable to other physical situations in which a strong noise limit plays a role., 9 pages, 2 figures, close to the published version. The text has been profoundly rewritten. The concept of "quantum spikes" is no longer discussed and will be studied in a subsequent article

The rounding of an analytical result is a process that should take into account the uncertainty of the result, which is in turn assessed during the validation exercise. Rounding rules are known in physical and analytical chemistry since a long time, but are often not used or misused in pharmaceutical analysis. The paper describes the theoretical background of the most common rules and their application to fix the rounding of results and specifications. The paper makes use of uncertainty values of impurity determination acquired during studies of reproducibility and intermediate precision with regards to 22 impurities of drug substances or drug products. As a general rule, authors propose the use of sound and well-established rounding rules to derive rounding from the results of the validation package.

Thermal contact is the archetype of non-equilibrium processes driven by constant non-equilibrium constraints when the latter are enforced by reservoirs exchanging conserved microscopic quantities. At a mesoscopic scale only the energies of the macroscopic bodies are accessible together with the configurations of the contact system. We consider a class of models where the contact system, as well as macroscopic bodies, have a finite number of possible configurations. The global system with only discrete degrees of freedom has no microscopic Hamiltonian dynamics, but it is shown that, if the microscopic dynamics is assumed to be deterministic and ergodic and to conserve energy according to some specific pattern, and if the mesoscopic evolution of the global system is approximated by a Markov process as closely as possible, then the mesoscopic transition rates obey three constraints. In the limit where macroscopic bodies can be considered as reservoirs at thermodynamic equilibrium (but with different intensive parameters) the mesoscopic transition rates turn into transition rates for the contact system and the third constraint becomes local detailed balance ; the latter is generically expressed in terms of the microscopic exchange entropy variation, namely the opposite of the variation of the thermodynamic entropy of the reservoir involved in a given microscopic jump of the contact system configuration. For a finite-time evolution after contact has been switched on we derive a fluctuation relation for the joint probability of the heat amounts received from the various reservoirs. The generalization to systems exchanging energy, volume and matter with several reservoirs, with a possible conservative external force acting on the contact system, is given explicitly., Comment: 26 pages. arXiv admin note: substantial text overlap with arXiv:1302.4538

The mechanistic bases for gene essentiality and for cell mutational resistance have long been disputed. The recent availability of large protein interaction databases has fuelled the analysis of protein interaction networks and several authors have proposed that gene dispensability could be strongly related to some topological parameters of these networks. However, many results were based on protein interaction data whose biases were not taken into account. In this article, we show that the essentiality of a gene in yeast is poorly related to the number of interactants (or degree) of the corresponding protein and that the physiological consequences of gene deletions are unrelated to several other properties of proteins in the interaction networks, such as the average degrees of their nearest neighbours, their clustering coefficients or their relative distances. We also found that yeast protein interaction networks lack degree correlation, i.e. a propensity for their vertices to associate according to their degrees. Gene essentiality and more generally cell resistance against mutations thus seem largely unrelated to many parameters of protein network topology.

We present an implementation in conformal field theory (CFT) of local finite conformal transformations fixing a point. We give explicit constructions when the fixed point is either the origin or the point at infinity. Both cases involve the exponentiation of a Borel subalgebra of the Virasoro algebra. We use this to build coherent state representations and to derive a close analog of Wick's theorem for the Virasoro algebra. This allows to compute the conformal partition function in non trivial geometries obtained by removal of hulls from the upper half plane. This is then applied to stochastic Loewner evolutions (SLE). We give a rigorous derivation of the equations, obtained previously by the authors, that connect the stochastic Loewner equation to the representation theory of the Virasoro algebra. We give a new proof that this construction enumerates all polynomial SLE martingales. When one of the hulls removed from the upper half plane is the SLE hull, we show that the partition function is a famous local martingale known to probabilists, thereby unravelling its CFT origin., 41 pages, 4 figures

We present a relation between conformal field theories (CFT) and radial stochastic Schramm-Loewner evolutions (SLE) similar to that we previously developed for the chordal SLEs. We construct an important local martingale using degenerate representations of the Virasoro algebra. We sketch how to compute derivative exponants and the restriction martingales in this framework. In its CFT formulation, the SLE dual Fokker-Planck operator acts as the two-particle Calogero hamiltonian on boundary primary fields and as the dilatation operator on bulk primary fields localized at the fixed point of the SLE map., Comment: 11 pages

We introduce a new oriented evolving graph model inspired by biological networks. A node is added at each time step and is connected to the rest of the graph by random oriented edges emerging from older nodes. This leads to a statistical asymmetry between incoming and outgoing edges. We show that the model exhibits a percolation transition and discuss its universality. Below the threshold, the distribution of component sizes decreases algebraically with a continuously varying exponent depending on the average connectivity. We prove that the transition is of infinite order by deriving the exact asymptotic formula for the size of the giant component close to the threshold. We also present a thorough analysis of aging properties. We compute local-in-time profiles for the components of finite size and for the giant component, showing in particular that the giant component is always dense among the oldest nodes but invades only an exponentially small fraction of the young nodes close to the threshold.

Classically, no transfer occurs between two equally filled reservoirs no matter how one looks at them, but the situation can be different quantum mechanically. This paradoxically surprising phenomenon rests on the distinctive property of the quantum world that one cannot stare at a system without disturbing it. It was recently discovered that this seemingly annoying feature could be harnessed to control small quantum systems using weak measurements. Here we present one of the simplest models -- an idealised double quantum dot -- where by toying with the dot measurement strength, i.e. the intensity of the look, it is possible to create a particle flux in an otherwise completely symmetric system. The basic property underlying this phenomena is that measurement disturbances are very different on a system evolving unitarily and a system evolving dissipatively. This effect shows that adaptive measurements can have dramatic effects enabling transport control but possibly inducing biases in the measurement of macroscopic quantities if not handled with care., Comment: Published version. Principal: 8 pages + references + 6 figures; Supplementary: 6 pages + references + 2 figures

We exhibit the invariance of cycle affinities in finite state Markov processes under various natural probabilistic constructions, for instance under conditioning and under a new combinatorial construction that we call ``drag and drop''. We show that cycle affinities have a natural probabilistic meaning related to first passage non-equilibrium fluctuation relations that we establish., Comment: 30 pages, 1 figure

Various approaches are compared for the design and analysis of studies to assess the transfer of an analytical method from a research and development site to one or more other sites: comparison of observed bias and precision to acceptance limits, statistical quality control-type analysis, statistical difference tests, and statistical equivalence tests. These approaches are evaluated in terms of the extent to which the risks of incorrect decisions (consumer risk of failing to detect that a site is unacceptable, and producer risk of rejecting an acceptable site) are known and/or controlled. Comparison of observed accuracy and precision to acceptance limits is a flawed approach because both the consumer and producer risks are unknown and uncontrolled. For technology transfer, where the objective is to demonstrate sufficient acceptability or similarity, the statistical quality control and difference tests are well known to suffer from illogical characteristics (decreasing true acceptance probabilities as the sample size increases). The equivalence test is the preferred approach because it alone controls the more important consumer risk and performs in a scientifically logical manner. Acceptance limits for accuracy and precision in the equivalence test should be based on need for intended use (ie, ensuring that good batches will pass, and bad batches will fail, during future release testing and stability testing), and a rigorous method for selection of well-conceived limits is presented. Methods for sample size determination are also included. The proposed approach is illustrated with two examples.

Alpine winter sports resorts can be considered as extended urban neighbourhoods of modern archipelago-type cities. Through their brochures, tour operators sell their intangible product by portraying an image of this city. The way in which tourists from various cultural backgrounds perceive the alpine resorts and create different expectations is examined through a comparative analysis of German, English, French, Japanese and Swedish brochures. The resort manager must be able to take into account the different aspirations of tourists of various nationalities using facilities which may have been perceived quite differently from one culture to another., Images des villes alpines chez les acteurs du tourisme The images of the alpine towns as perceived by tourism players Michel Bauer Résumé : Les stations de sport d'hiver représentent les quartiers urbains d'une ville éclatée en archipel. Les Tours opérateurs, marchands d'un produit intangible et animateurs de ces villes, diffusent une image de celles-ci à travers leurs brochures. Une analyse comparative de catalogues allemands, anglais, français, japonais et suédois fait alors ressortir comment les touristes des stations alpines imaginent leur espace et comment ces regards culturellement divers construisent des réalités différentes. Le rôle du manager de la station est alors de gérer les contradictions de ces différents rêves et d'organiser des flux d'habitants ayant des attentes différentes en fonction de ces images définies à partir des mêmes équipements., Bauer Michel. Images des villes alpines chez les acteurs du tourisme. In: Revue de géographie alpine, tome 87, n°1, 1999. pp. 131-142.

The apparent triumph of economic rationality, the globalization of firms and the construction of the European Union all suggest that the ways of making top leaders in big German, British and French companies should be converging since these firms must cope with the same constraints. This argument, however appealing, overlooks the social dimension of the making of elites. A comparison of the heads of the 200 biggest British, French and German firms brings to light three contrasting national models for producing legitimate authority and thus sheds light on three quite different types of business elites. This is a far cry from a single European model, far indeed given that each of these three models for the making of a business elite has roots in each country’s historical and social ‘logics’. This fact endows these models with stability and makes it quite hard for a European model to even gradually emerge.

Dissolution efficiency (D.E.), the area under a dissolution curve between defined time points, and the fit factors (f1 and f2) have been compared for the characterisation of dissolution profiles, using data from three batches of a product in nine different packs stored under two conditions. The factors f1 and f2 offer ease of calculation and a simple measure of similarity between pairs of dissolution profiles. This is well suited to the qualitative determination of 'similarity' as required by the FDA's SUPAC Guide. However, they do not provide information on individual batches, including their consistency. In contrast, D.E. does provide such information is well-suited to making quantitative comparisons amongst batches. Because D.E. has a simple physical meaning, it is easier to interpret D.E. data then corresponding f1 and f2 results. The confidence limits in D.E. values provide a useful measure of the variability in batch dissolution and allow the statistical significance of difference in D.E. between pairs of batches to be determined. Both of the above measures lead to the same conclusions regarding the similarity in protective power amongst the nine packs under test and to the value of added desiccant in maintaining the dissolution profile of the product when stored under high humidity conditions. It is concluded that D.E. offers a suitable alternative to the single point dissolution measurement for QC of immediate release products.

Irbesartan, a novel anti-hypertensive agent (Angiotensin II antagonist), has been found to exist in two crystal forms. The solution-state structure and the solid-state structure of the two forms, designated Form A and Form B, have been probed using a series of NMR methods and correlated with single-crystal X-ray results for Form B. The prototropic tautomerism generally exhibited by tetrazole ring systems has been probed using solid-state NMR and it is seen that Irbesartan offers a rare example of desmotropic behaviour, whereby the isolated crystal forms are stable in the solid state yet related through a tautomeric equilibrium in the solution state. Nitrogen-15 solid-state CPMAS data have been used to understand the structures of the stable Irbesartan crystal forms. Form B is shown to undergo an exchange process involving the tetrazole ring. Two-dimensional EXSY 15N spectra are used to understand this process, which involves simultaneous proton-hopping and internal rotation.

We examine the proposal made recently that the su(3) modular invariant partition functions could be related to the geometry of the complex Fermat curves. Although a number of coincidences and similarities emerge between them and certain algebraic curves related to triangular billiards, their meaning remains obscure. In an attempt to go beyond the su(3) case, we show that any rational conformal field theory determines canonically a Riemann surface., 56 pages, 4 eps figures, LaTeX, uses epsf

The author presents a synthesis of research on the concept of territory in the field of tourism, taking into consideration the point of view of visitors, local population, politics an dpublic administration, as well as organizers and sales persons. His research is based on the results of studies in the alpine region as one of the most important tourism areas.

Using the coset construction, we compute the root multiplicities at level-3 for some hyperbolic Kac–Moody algebras including the basic hyperbolic extension of A11 and E10.

A quantum system in contact with a heat bath undergoes quantum transitions between energy levels upon absorption or emission of energy quanta by the bath. These transitions remain virtual unless the energy of the system is measured repeatedly, even continuously in time. Isolating the two indispensable mechanisms in competition, we describe in a synthetic way the main physical features of thermally activated quantum jumps. Using classical tools of stochastic analysis, we compute in the case of a two-level system the complete statistics of jumps and transition times in the limit when the typical measurement time is small compared to the thermal relaxation time. The emerging picture is that quantum trajectories are similar to those of a classical particle in a noisy environment, subject to transitions a la Kramer in a multi-well landscape, but with a large multiplicative noise., 17 pages, 1 figure, to be published version

We analyze general enough models of repeated indirect measurements in which a quantum system interacts repeatedly with randomly chosen probes on which Von Neumann direct measurements are performed. We prove, under suitable hypotheses, that the system state probability distribution converges after a large number of repeated indirect measurements, in a way compatible with quantum wave function collapse. Similarly a modified version of the system density matrix converges. We show that the convergence is exponential with a rate given by some relevant mean relative entropies. We also prove that, under appropriate rescaling of the system and probe interactions, the state probability distribution and the system density matrix are solutions of stochastic differential equations modeling continuous-time quantum measurements. We analyze the large time convergence of these continuous-time processes and prove convergence., 44 pages, no figure

Crystalline polymorphism occurs frequently in the solid state of active pharmaceutical ingredients, and this is problematic for the development of a suitable dose form. Rimonabant, an active pharmaceutical ingredient developed by Sanofi and discontinued because of side effects, exhibits dimorphism; both solid forms have nearly the same melting temperatures, melting enthalpies, and specific volumes. Although the problem may well be academic from an industrial point of view, the present case demonstrates the usefulness of constructing pressure–temperature phase diagrams by direct measurement as well as by topological approach. The system is overall monotropic and form II is the more stable solid form. Interestingly, the more stable form does not possess any hydrogen bonds, whereas the less stable one does. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 102:2311–2321, 2013

We describe a measurement device principle based on discrete iterations of Bayesian updating of system state probability distributions. Although purely classical by nature, these measurements are accompanied with a progressive collapse of the system state probability distribution during each complete system measurement. This measurement scheme finds applications in analysing repeated non-demolition indirect quantum measurements. We also analyse the continuous time limit of these processes, either in the Brownian diffusive limit or in the Poissonian jumpy limit. In the quantum mechanical framework, this continuous time limit leads to Belavkin equations which describe quantum systems under continuous measurements., 23 pages, 1 figure. To be published in J. Phys. A

La methode « cœur de metier » permet aux organisations de s’interroger sur leur projet et leurs finalites. Elle suppose de hierarchiser les actions menees en fonction de la valeur creee. Dans le secteur marchand, celle-ci s’apprecie de maniere relative en comparant les resultats economiques obtenus par des firmes. Dans le secteur public, en l’absence de referentiel de marche, la valeur creee s’apprecie non seulement en fonction des couts mais aussi de la contribution aux ambitions de l’action publique. Cet article presente une recherche sur l’avenir du cœur de metier des organismes de securite sociale (OSS), qui a permis de retenir deux scenarios prospectifs. Le premier retient un mode classique de creation de valeur fonde sur la mise en actes de la reglementation. Le second repose sur la capacite des OSS a s’adapter a un environnement evolutif et pose de nouveaux modes d’actions, en privilegiant par exemple la prevention a la reparation. Il elargit le cœur de metier a une variete d’activites et fonde la creation de valeur sur la qualite de sa contribution a l’efficacite des depenses publiques en matiere sanitaire et sociale.

These notes are meant as a gentle introduction to the concepts of Loewner chains, local growth, Stochastic Loewner Evolutions (SLE) and their relationships to Conformal Field Theories (CFT). These concepts have played an important role in physics and mathematics during the recent years. The first section describes two discrete examples, the exploration process and loop-erased random walks. It can be read almost without any prerequisites. The aim is to show that even for curves defined purely in geometrical terms, it is useful to have a statistical mechanics viewpoint where the measure on curves is derived from a measure on local degrees of freedom of some model. A third model, diffusion-limited aggregation (DLA) is also introduced. The second section introduces Loewner chains and their relevance for the description of growth processes. A prerequisite is a minimal knowledge of complex analysis. The third section contains the derivation of the relevance of SLE in the description of interfaces when two properties, conformal invariance and the domain Markov property, are assumed/proved. The prerequisites are some knowledge of complex analysis and probability theory. The last section outlines the relation with Conformal Field Theory. This relation is via martingales and singular vectors. Again, the reader is assumed to have some basic knowledge of complex analysis and probability theory, and some familiarity with CFT. The discussion is informal. There is little or no claim at originality. We try to give some intuition based on explicit examples.

Both the classical time-ordering and the Magnus expansion are well known in the context of linear initial value problems. Motivated by the noncommutativity between time-ordering and time derivation, and related problems raised recently in statistical physics, we introduce a generalization of the Magnus expansion. Whereas the classical expansion computes the logarithm of the evolution operator of a linear differential equation, our generalization addresses the same problem, including, however, directly a non-trivial initial condition. As a by-product we recover a variant of the time-ordering operation, known as $${\mathsf{T}^\ast}$$ -ordering. Eventually, placing our results in the general context of Rota–Baxter algebras permits us to present them in a more natural algebraic setting. It encompasses, for example, the case where one considers linear difference equations instead of linear differential equations.