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Advanced age is the major risk factor for idiopathic Parkinson's disease (PD), but to date the biological relationship between PD and ageing remains elusive. Here we describe the rationale and the design of the H2020 funded project "PROPAG-AGEING", whose aim is to characterize the contribution of the ageing process to PD development. We summarize current evidences that support the existence of a continuum between ageing and PD and justify the use of a Geroscience approach to study PD. We focus in particular on the role of inflammaging, the chronic, low-grade inflammation characteristic of elderly physiology, which can propagate and transmit both locally and systemically. We then describe PROPAG-AGEING design, which is based on the multi-omic characterization of peripheral samples from clinically characterized drug-naive and advanced PD, PD discordant twins, healthy controls and "super-controls", i.e. centenarians, who never showed clinical signs of motor disability, and their offspring. Omic results are then validated in a large number of samples, including in vitro models of dopaminergic neurons and healthy siblings of PD patients, who are at higher risk of developing PD, with the final aim of identifying the molecular perturbations that can deviate the trajectories of healthy ageing towards PD development.

The efficient generation of renewable energies from solar radiation implies the precise knowledge of the thermophysical properties of the materials and systems involved in such applications, this knowledge is fundamental, since it allows us to evaluate and optimize the performance of materials and methods. One of the great challenges for the efficient use of solar energy is the study of the phenomena involved in the interaction of radiation with matter, and the conversion of energy absorbed into heat. Photothermal and thermographic techniques are ideal methodologies to study these phenomena, since they are non-contact techniques (NCT) and, therefore, can be applied in a wide range of operating temperatures and environments. In general, photothermal techniques consist in illuminating the surface of the sample with a laser light beam modulated or pulsed, therefore the sample is heated and emits infrared radiation IR (among other types of energy). The variations of the IR energy are related to the thermophysical properties of the specimens photothermal techniques are based on the detection of these variations. Some examples of photothermal methodologies are the photothermal radiometry pulsed (PPTR) and modulated (PTR), the photothermal reflectometry (RM) and the thermal wave resonant cavity (TWRC). Infrared thermography is a powerful method of non-contact measurement, using this technique thermal images or thermograms are obtained, which are a representation of the temperature distribution on the surface of an object or a scene. The thermophysical properties of materials they are obtained through the analysis of amplitude and phase signals, as well as thermograms. Reflectance spectroscopy is a powerful tool for characterizing the optical properties (solar absorbance and thermal emittance) of a great diversity of materials applied in solar technology. The analysis can be done in two wavelength ranges of interest: Ultraviolet/visible/near infrared and medium infrared, where solar spectrum radiation wavelengths and infrared emission range are located respectively. The methodologies mentioned have been applied in the characterization of materials at room temperature, however, many processes involved in the new applications of solar energy occur at high temperature. It has also been shown that thermophysical mechanisms related to the conversion of energy that occur at room temperature are not dominant in high temperature regimes therefore, the measurement of the conversion, absorption, emission and energy exchange processes to high temperature, they involve new technological challenges. In this work, we present a summary about the photothermal, thermographic and reflectance spectroscopy techniques, used in the evaluation of the thermophysical properties of solar absorbers applied in low temperature solar systems, as well as high temperature concentrate solar power (CSP) systems.

Chondroblastoma is a rare, benign cartilaginous neoplasm that accounts for approximately 1% of all bone tumors, and approximately 4% of all chondroblastomas arise in the clavicle. Here, we report a case of chondroblastoma in the right clavicle. 27-year-old female patient presented with a 12-month history of shoulder pain. Based on radiological and pathological examination, the diagnosis was compatible with chondroblastoma. After resection of the tumor, 1 cm of the distal clavicle was preserved, 15 cm of the non-vascularized fibula was taken from the contralateral leg and placed on the site of the clavicle and fixed with hook plate at distal clavicle and reconstruction plate attached to the sternum. 13 months of follow-up is scheduled for removal of osteosynthesis material, finding full consolidation of sternoclavicular segment and the distal segment. A good functional outcome was apparent after a limited 14-month follow-up, and the patient was highly satisfied with the result. We found no recurrence or metastasis.

Measures of semantic relatedness have been used in a variety of applications in information retrieval and language technology, such as measuring document similarity and cohesion of text. Definitions of such measures have ranged from using distance-based calculations over WordNet or other taxonomies to statistical distributional metrics over document collections such as Wikipedia or the Web. Existing measures do not explicitly consider the domain associations of terms when calculating relatedness: This article demonstrates that domain matters. We construct a data set of pairs of terms with associated domain information and extract pairs that are scored nearly identical by a sample of existing semantic-relatedness measures. We show that human judgments reliably score those pairs containing terms from the same domain as significantly more related than cross-domain pairs, even though the semantic-relatedness measures assign the pairs similar scores. We provide further evidence for this result using a machine learning setting by demonstrating that domain is an informative feature when learning a metric. We conclude that existing relatedness measures do not account for domain in the same way or to the same extent as do human judges.

The efficiency of the conversion of solar energy into thermal energy is determined by the optical and thermal properties of the selective coating, in particular, the solar absorptance and thermal emittance at the desired temperature of the specific application. Photothermal techniques are the most appropriate methods to explore these properties, however, a quantitative determination using photothermal radiometry, which is based on the measurement of emitted radiation caused by the heating generated by a modulated light source, has proven to be elusive. In this work, we present experimental results for selective coatings based on electrodeposited black nickel–nickel on both stainless steel and copper substrates, as well as for commercial TiNOX coatings on aluminum, illustrating that the radiation emitted by the surface depends on the optical absorption, thermal emissivity and on the light-into-heat energy conversion efficiency (quantum efficiency). We show that a combination of photothermal radiometry and photoacoustic spectroscopy can successfully account for these parameters, and provide values for the emissivity in agreement with values obtained by Fourier-transform infrared spectroscopy.

Concentrating solar power (CSP) systems use solar absorbers to convert sunlight into thermal electric power. In CSP systems, a high reflective surface focuses sunlight onto a receiver that captures the solar energy and converts it into heat. The operation of high efficiency CSP systems involves improvements in the performance of the coatings of the solar absorption materials. To accomplish this, novel, more efficient selective coatings are being developed with high solar absorptance and low thermal losses at their operation temperature. Heat losses in a CSP system occur by three mechanisms: conduction, convection and radiation. It has been widely documented that energy losses increase with increasing operating temperature of CSP systems, and the precise knowledge of the thermophysical properties of the materials involved in CSP systems may allow us to increase the efficiency of systems. In this work, we applied the pulsed photoradiometry technique (PPTR) to evaluate the changes in the thermophysical prope...

This review paper summarises the recent, on-going, and future research activities in precise positioning at Laval University. The projects undertaken by the GPS and Geodesy Research Group are presented following three main research topics. The first one deals with the use of precise positioning for deformation monitoring of engineering structures. The study of ice forces on dams using a robotic total station and the improvement of GPS height determination using multiple GPS antennas linked to a single receiver with calibrated fiber optics are presented. A second topic of research is the crustal deformation of the Charlevoix seismic zone in Quebec. This study uses GPS and levelling techniques and involves an investigation of the temporal stability of the GPS permanent stations available in the surrounding area. Finally, research on single GPS receiver positioning techniques is presented, namely, Precise Point Positioning (PPP) and Time Relative Positioning (TRP).

A limitation of GPS positioning is that the vertical component is generally two to three times less precise than the horizontal components. In a previous work by R. Santerre of Laval University and G. Beutler of University of Bern, it was shown in simulations that it is possible to improve the GPS vertical positioning precision by using a multi-antenna GPS receiver and a precise calibration technique of the relative hardware delay between the antennas and the receiver. However, no actual implementation of the system was done to prove the concept until now. A new multi-antenna, GPS-over-fiber architecture with real-time delay monitoring, designed and implemented to improve the vertical precision is presented. The improvement in vertical precision arises from the elimination of the relative receiver clock error in single difference, between antennas, and the precision real-time calibration of the relative hardware delay. Experiments were conducted with a zero baseline and a short baseline configuration. The results show, as expected by the theory and the simulations, a two to three times improvement in the precision of the vertical component such that it reached the same level of performance as the horizontal components. These promising results will enable the use of this type of configuration in several applications where the same precision in all 3D components is essential and could not be achieved before with standard GPS positioning techniques.

International audience; The infrared emissivity of glassy carbon, stainless steel, and stainless steel with a selective coating of NiNiO has been determined using a thermal-wave resonant cavity heated with a modulated laser beam. This is achieved performing a length scan of the cavity at a fixed frequency of 5 Hz. It is observed experimentally that (1) the mechanisms of heat conduction and radiation co-exist inside the cavity, through the coupling of the dc and ac components of the temperature, and (2) the radiation effect shows up in both the amplitude and phase signals for cavity thicknesses greater than the diffusion length of the intra-cavity air. Using a suitable theoretical model, the experimental data for the amplitude and phase have allowed the determination of the infrared emissivity of the studied materials.

Selective solar absorbing coating consists of a high thermal reflectance layer and high solar absorbance layer deposited over a substrate. In this work optical and thermal properties of high reflective surface were characterized with infrared photothermal radiometry and photoacoustic spectroscopy

We present and evaluate MKBUILD , a tool for creating domain-specific ontologies. These ontologies, which we call Modular Knowledge Bases (MKBs), contain concepts and associations imported from existing large-scale knowledge resources, in particular WordNet and Wikipedia. The combination of WordNet's human-crafted taxonomy and Wikipedia's semantic associations between articles produces a highly connected resource. Our MKBs are used by a conversational agent operating in a small computational environment. We constructed several domains with our technique, and then conducted an evaluation by asking human subjects to rate the domain-relevance of the concepts included in each MKB on a 3-point scale. The proposed methodology achieved precision values between 71% and 88% and recall between 37% and 95% in the evaluation, depending on how the middle-score judgements are interpreted. The results are encouraging considering the cross-domain nature of the construction process and the difficulty of representing concepts as opposed to terms.

We propose a GPS-over-fiber solution that allows relative delay monitoring with millimetric precision and uplink transmission of down-converted GPS signal. Experimentations with directly modulated semiconductor devices show that it is suitable for high precision measurements.