DAZIO: detecting activity zones based on input/output call and SMS activity

Mobile telecoms operators possess an enormous quantity of data, which could be used to reduce the cost of installing new infrastructure, to provide a better QoS or to plan their infrastructure. Thus, they are concerned to model, understand and predict SMS and calls activity levels in their infrastructures. Besides, SMS and call activities analysis can open new business opportunities for geomarketing as well as trade area analysis. In the present effort, we detected activity zones with a difference of only 0.5 km from the reference activity areas extracted from Geo-tweets. We also used Markov chains to represent and predict SMS and call activity levels, achieving a prediction success rate between 80% and 90%

Candidate quantum spin ice in the pyrochlore Pr2_2Hf2_2O7_7

We report the low temperature magnetic properties of the pyrochlore Pr$_2$Hf$_2$O$_7$. Polycrystalline and single-crystal samples are investigated using time-of-flight neutron spectroscopy and macroscopic measurements, respectively. The crystal-field splitting produces a non-Kramers doublet ground state for Pr$^{3+}$, with Ising-like anisotropy. Below 0.5 K ferromagnetic correlations develop, which suggests that the system enters a spin ice-like state associated with the metamagnetic behavior observed at $\mu_0H_c\sim2.4$~T. In this regime, the development of a discrete inelastic excitation in the neutron spectra indicates the appearance of spin dynamics which are likely related to cooperative quantum fluctuations.Comment: 7 pages, 5 figures, 1 tabl

La cicatrisation du tendon et la récupération des amplitudes articulaires après chirurgie de la coiffe des rotateurs par arthroscopie: influence d'un protocole de rééducation précoce comparé à un protocole d'immobilisation : revue de la littérature : travail de Bachelor

Introduction : Dans le domaine des pathologies de l’épaule, la plus rencontrée est la rupture de/des tendons de la coiffe des rotateurs. Après chirurgie réparatrice par arthroscopie différents protocoles de rééducation sont appliqués. Récemment cités comme la cause des récidives, ces protocoles de rééducation sont au cœur d’une controverse sur les résultats cliniques post-opératoires. L’objectif de cette revue est d’identifier les répercussions d’un protocole de rééducation incluant de la mobilisation passive précoce (J1) comparé à un protocole d’immobilisation, après chirurgie réparatrice de la coiffe des rotateurs par arthroscopie, sur la cicatrisation tendineuse et les amplitudes articulaires, avec un recul d’une année. Problématique : «La mobilisation immédiate passive (J1) après chirurgie de la coiffe des rotateurs par arthroscopie, est-elle préjudiciable à la cicatrisation complète du/des tendon(s), augmente t-elle le risque de récidive et est-elle bénéfique à la récupération des amplitudes articulaires ?» Méthode : Nous avons effectué notre recherche sur les bases de données suivantes : Medline, Cochrane library, PEDro, et Kinédoc. Nous avons inclus 4 études de design RCT analysant des patients ayant bénéficié d’une chirurgie réparatrice effectuée par arthroscopie et comprenant la comparaison d’un protocole de rééducation précoce avec un protocole d’immobilisation. Résultats : Ces 4 publications ne reportent aucun avantage significatif dans l’application d’un protocole précoce comparé à un protocole d’immobilisation. Cependant, l’application d’un protocole d’immobilisation a tendance à induire une meilleure cicatrisation sans effets néfastes sur la récupération des amplitudes articulaires. Conclusion : Des résultats presque similaires sont obtenus avec les deux protocoles de rééducation après une année. Les auteurs se questionnent maintenant sur l’application de protocoles individualisés à chaque patient.Introduction : The most common pathologies encountered in the area of shoulder disorders are rotators cuff’s tendons tears. After reconstructive surgery by arthroscopy, several rehabilitation protocols can be applied. Those protocols have been identified by some in the literature as the cause of recurrence and are therefore at the heart of a controversy about the post-operation outcomes. The goal of this review is to identify the effects of two types of protocols. The two protocols differ in terms of the timing of the mobilization after reconstructive surgery of the cuff by arthroscopy. We will discuss the effects of an early mobilization versus immobilization on the healing of the tendon and the range of motion one year after the operation. Main questions : "Is the immediate passive mobilization (J1) detrimental to the complete healing of the tendon? Does an immediate mobilization increase the risk of recurrence and is it beneficial in terms of the amplitude of the shoulder motion?” Methods : We reviewed the literature by including publications found in the following databases: Cochrane library, PEDro and Kinedoc. We have concentrated in particular on four design RCT studies that analyze patients having benefited from a reconstructive surgery by arthroscopy. Those studies compare an early versus late mobilization protocol in the rehabilitation stage. Results : In all four studies there is no evidence of a significant improvement of an early mobilization versus immobilization protocol. Nevertheless, late protocols tend to result in a better healing with no negative impact on the range motion at one year. Conclusion : Based on those four studies, it is not possible to favor one rehabilitation protocol. The authors therefore discuss a future area of research, mainly the establishment of a protocol specific to each patient

Simulating rhizodeposition as a function of shoot and root interactions within a new 3D Functional-Structural Plant Model

Introduction - Rhizodeposition, i.e. the release of organic materials by roots, represents a significant portion of plant's carbon (C) budget, ranging from 5% to 15% of net photosynthesized C (Pausch and Kuzyakov, 2018). Various rhizodeposits can be released by roots, e.g. soluble exudates, secreted mucilage, sloughed cells, or volatile organic compounds. Despite their short lifetime, some of these products have been shown to favor plant growth, e.g. by increasing water and nutrient uptake. Among rhizodeposition processes, exudation has been suggested to depend on the concentration of carbohydrates inside the roots (Personeni et al., 2007). However, rhizodeposition not only depends on the availability of C in the roots, but also on the architecture of the root system, and many have shown that rhizodeposits are more concentrated in specific areas, such as root tips. Consequently, a Functional-Structural Plant Model (FSPM) would theoretically represent the best framework for simulating the spatial and temporal dynamics of rhizodeposition, as it can describe the evolution of both the metabolism and the architecture of the plant. The objective of this work is to create such a framework by coupling a whole-plant FSPM, a 3D root architectural model, and a new model simulating rhizodeposition. Modelling approach - Our strategy has been to combine the FSPM CN-Wheat (Barillot et al., 2016), which describes the main processes of C and nitrogen (N) acquisition and transformation by an individual wheat plant and the 3D growth and development of its aerial organs, with the model ArchiSimple (Pagès et al., 2014) that simulates the development of the 3D root architecture for a range of plant species, and the new model RhizoDep, which calculates a full C balance in each part of a root system in order to simulate local rhizodeposition fluxes. The complementarity of the three models is illustrated in Figure 1: i) CN-Wheat is used to calculate the amount of C allocated from the shoots to the roots, ii) ArchiSimple provides the 3D structure of the root system, and iii) RhizoDep distributes the C provided by the shoots within the 3D root system and simulates the actual growth, respiration and rhizodeposition of each root element based on C availability. The major link between the three models lies in the exchange of C between aboveground and belowground tissues, which is driven by gradients of sucrose concentration in the different compartments of the plant. Preliminary results & short-term perspectives - The coupling of the three models has been started using the OpenAlea platform and its Multiscale Tree Graph formalism (Pradal et al., 2008). First simulations were done using the allocation of C to the roots simulated by CN-Wheat as an input to the root model based on the effective coupling of ArchiSimple and RhizoDep. These simulations show how rhizodeposition is intrinsically dependent on the architecture of the root system and on the total amount of available C. For completing the coupling, several issues still need to be tackled, e.g. how N uptake and metabolism should be spatialized in a 3D root system, how it may be regulated by local C and N availability, and how rhizodeposition can modify soil N availability. However, this modelling approach has already led to a first prototype able to simulate rhizodeposition processes on a dynamic, 3D root system that is fully integrated within the functioning of the whole plant. Its refinement will offer unique opportunities to study the possible link between rhizodeposition and the environmental factors affecting plant growth, e.g. atmospheric CO2 concentration or soil N availability

In Vitro Red Blood Cell Segregation in Sickle Cell Anemia

Red blood cells in sickle cell anemia (sRBC) are more heterogeneous in their physical properties than healthy red blood cells, spanning adhesiveness, rigidity, density, size, and shape. sRBC with increased adhesiveness to the vascular wall would trigger vaso-occlusive like complications, a hallmark of sickle cell anemia. We investigated whether segregation occurs among sRBC flowing in micron-sized channels and tested the impact of aggregation on segregation. Two populations of sRBC of different densities were separated, labeled, and mixed again. The mixed suspension was flowed within glass capillary tubes at different pressure-drops, hematocrit, and suspending media that promoted or not cell aggregation. Observations were made at a fixed channel position. The mean flow velocity was obtained by using the cells as tracking particles, and the cell depleted layer (CDL) by measuring the distance from the cell core border to the channel wall. The labeled sRBC were identified by stopping the flow and scanning the cells within the channel section. The tube hematocrit was estimated from the number of fluorescence cells identified in the field of view. In non-aggregating media, our results showed a heterogeneous distribution of sRBC according to their density: low-density sRBC population remained closer to the center of the channel, while the densest cells segregated towards the walls. There was no impact of the mean flow velocity and little impact of hematocrit. This segregation heterogeneity could influence the ability of sRBC to adhere to the vascular wall and slow down blood flow. However, promoting aggregation inhibited segregation while CDL thickness was enhanced by aggregation, highlighting a potential protective role against vaso-occlusion in patients with sickle cell anemia

Reasoning over Time into Models with DataTime

International audienceModels at runtime have been initially investigated for adaptive systems. Models are used as a reflective layer of the current state of the system to support the implementation of a feedback loop. More recently, models at runtime have also been identified as key for supporting the development of full-fledged digital twins. However, this use of models at runtime raises new challenges, such as the ability to seamlessly interact with the past, present and future states of the system. In this paper, we propose a framework called DataTime to implement models at runtime which capture the state of the system according to the dimensions of both time and space, here modeled as a directed graph where both nodes and edges bear local states (ie. values of properties of interest). DataTime offers a unifying interface to query the past, present and future (predicted) states of the system. This unifying interface provides i) an optimized structure of the time series that capture the past states of the system, possibly evolving over time, ii) the ability to get the last available value provided by the system's sensors, and iii) a continuous micro-learning over graph edges of a predictive model to make it possible to query future states, either locally or more globally, thanks to a composition law. The framework has been developed and evaluated in the context of the Intelligent Public Transportation Systems of the city of Rennes (France). This experimentation has demonstrated how DataTime can be used for managing data from the past, the presentand the future, and facilitate the development of digital twins