Beyond the Pixel: a Photometrically Calibrated HDR Dataset for Luminance and Color Prediction

Light plays an important role in human well-being. However, most computer vision tasks treat pixels without considering their relationship to physical luminance. To address this shortcoming, we introduce the Laval Photometric Indoor HDR Dataset, the first large-scale photometrically calibrated dataset of high dynamic range 360{\deg} panoramas. Our key contribution is the calibration of an existing, uncalibrated HDR Dataset. We do so by accurately capturing RAW bracketed exposures simultaneously with a professional photometric measurement device (chroma meter) for multiple scenes across a variety of lighting conditions. Using the resulting measurements, we establish the calibration coefficients to be applied to the HDR images. The resulting dataset is a rich representation of indoor scenes which displays a wide range of illuminance and color, and varied types of light sources. We exploit the dataset to introduce three novel tasks, where: per-pixel luminance, per-pixel color and planar illuminance can be predicted from a single input image. Finally, we also capture another smaller photometric dataset with a commercial 360{\deg} camera, to experiment on generalization across cameras. We are optimistic that the release of our datasets and associated code will spark interest in physically accurate light estimation within the community. Dataset and code are available at https://lvsn.github.io/beyondthepixel/

The use of muscle strength assessed with handheld dynamometers as a non-invasive biological marker in myotonic dystrophy type 1 patients: a multicenter study

<p>Abstract</p> <p>Background</p> <p>Myotonic dystrophy type 1 (DM1) is a multisystem disorder that demonstrates variable symptoms and rates of progression. Muscle weakness is considered one of the main problems with a clinical picture that is characterized by distal weakness of the limbs progressing to proximal weakness. The main objective of this study was to characterize the maximal strength of ankle eversion and dorsiflexion in DM1 patients. Manual and handheld dynamometer (HHD) muscle testing were also compared.</p> <p>Methods</p> <p>The maximal strength of 22 patients from Quebec (mean age = 41,1 ± 13,8) and 24 from Lyon (mean age = 41,6 ± 10,2) were compared to 16 matched controls.</p> <p>Results</p> <p>With the use of HHD, an excellent reproducibility of the torque measurements was obtained for both centers in eversion (R²= 0,94/Quebec; 0,89/Lyon) and dorsiflexion (R²= 0,96/Quebec; 0,90/Lyon). The differences between 3 groups of DM1 (mild, moderate, severe) and between them and controls were all statistically significant (p < 0,001). No statistical differences between sites were observed (p > 0.05). The degree of muscle strength decline in dorsiflexion (eversion) were 60% (47%), 77% (71%), and 87% (83%) for DM1 with mild, moderate, and severe impairments, respectively. The smallest mean difference between all DM1 patients taking together was 2.3 Nm, a difference about twice than the standard error of measurement. There was a strong relationship between eversion and dorsiflexion strength profiles (R²= 0,87;Quebec/0,80;Lyon). Using a 10-point scale, manual muscle testing could not discriminate between the 3 groups of DM1 patients.</p> <p>Conclusions</p> <p>The HHD protocol showed discriminative properties suitable for multicentre therapeutic trial. The present results confirmed the capacity of quantitative muscle testing to discriminate between healthy and DM1 patients with different levels of impairments. This study is a preliminary step for the implementation of a valid, reliable and responsive clinical outcome for the measurement of muscle impairments with this population.</p

Header for SPIE use Geometrical misalignment retrieval of the IASI interferometer

ABSTRACT The IASI instrument (Infrared Atmospheric Sounding Interferometer) is a Fourier-Transform Spectrometer (FTS) providing spectra of the Earth&apos;s atmosphere observed from space. The heart of the instrument is a Michelson interferometer (IHOS) equipped with two hollow cube-corners retro-reflectors in place of the classical flat mirrors. The main alignment requirements of the IASI interferometer are the lateral shift, or shear, of the moving cube-corner (seen through the beamsplitter) and the misalignment of its scanning axis : these contributions should not exceed 20 µm and 250 µrad respectively during the five years mission in orbit. Thus the most difficult challenge of the IHOS integration on-ground probably is their measurement accuracy, which shall respectively be better than 1 µm and 100 µrad. The envisaged characterization method consists in a specific data processing of the fringe patterns created by the interferometer at four different points located in the IHOS Field of View (FoV), corresponding to the IASI instrument pixels. For each acquired interferogram the Optical Path Differences (OPD) created by the interferometer are evaluated using a double Fouriertransform algorithm, and the results are combined together in order to retrieve the apparent trajectory of the mobile cubecorner. This principle was tested on a breadboard interferometer already assembled in the CNES laboratories. The numerical results presented herein tend to demonstrate the efficiency of the method, since the achieved accuracy does not exceed 1.2 µm (whatever the cube-corner axial position) and 120 µrad respectively. The main error sources also are discussed

Dossier. La relation philosophie-théologie hier et aujourd’hui

Avant-propos Le présent dossier réunit quelques-unes des contributions données lors de la séance académique organisée à l’Institut de France (Paris) le 9 décembre 2011, à l’occasion de la publication de l’Anthologie Philosophie et théologie (4 tomes) achevée en 2011 aux éditions du Cerf sous la direction de Philippe Capelle-Dumont, en collaboration avec Jean Greisch et Geneviève Hébert (Tome IV), Jean-Christophe Bardout (Tome III), Olivier Boulnois (Tome II), Jérôme Alexandre (Tome I) et de 9..

Comparison between fused silica of type II and III after surface heating with a CO2 laser

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Time-Controlled Adaptive Ventilation Does Not Induce Hemodynamic Impairment in a Swine ARDS Model

International audienceBackground The current standard of care during severe acute respiratory distress syndrome (ARDS) is based on low tidal volume (VT) ventilation, at 6 mL/kg of predicted body weight. The time-controlled adaptive ventilation (TCAV) is an alternative strategy, based on specific settings of the airway pressure release ventilation (APRV) mode. Briefly, TCAV reduces lung injury, including: (1) an improvement in alveolar recruitment and homogeneity; (2) reduction in alveolar and alveolar duct micro-strain and stress-risers. TCAV can result in higher intra-thoracic pressures and thus impair hemodynamics resulting from heart-lung interactions. The objective of our study was to compare hemodynamics between TCAV and conventional protective ventilation in a porcine ARDS model. Methods In 10 pigs (63–73 kg), lung injury was induced by repeated bronchial saline lavages followed by 2 h of injurious ventilation. The animals were then randomized into two groups: (1) Conventional protective ventilation with a VT of 6 mL/kg and PEEP adjusted to a plateau pressure set between 28 and 30 cmH 2 O; (2) TCAV group with P-high set between 27 and 29 cmH 2 O, P-low at 0 cmH 2 O, T-low adjusted to terminate at 75% of the expiratory flow peak, and T-high at 3–4 s, with I:E &gt; 6:1. Results Both lung elastance and PaO 2 :FiO 2 were consistent with severe ARDS after 2 h of injurious mechanical ventilation. There was no significant difference in systemic arterial blood pressure, pulmonary blood pressure or cardiac output between Conventional protective ventilation and TCAV. Levels of total PEEP were significantly higher in the TCAV group ( p &lt; 0.05). Driving pressure and lung elastance were significantly lower in the TCAV group ( p &lt; 0.05). Conclusion No hemodynamic adverse events were observed in the TCAV group compared as to the standard protective ventilation group in this swine ARDS model, and TCAV appeared to be beneficial to the respiratory system

New insights into sulfur metabolism in yeasts as revealed by studies of Yarrowia lipolytica.

Yarrowia lipolytica, located at the frontier of hemiascomycetous yeasts and fungi, is an excellent candidate for studies of metabolism evolution. This yeast, widely recognized for its technological applications, in particular produces volatile sulfur compounds (VSCs) that fully contribute to the flavor of smear cheese. We report here a relevant global vision of sulfur metabolism in Y. lipolytica based on a comparison between high- and low-sulfur source supplies (sulfate, methionine, or cystine) by combined approaches (transcriptomics, metabolite profiling, and VSC analysis). The strongest repression of the sulfate assimilation pathway was observed in the case of high methionine supply, together with a large accumulation of sulfur intermediates. A high sulfate supply seems to provoke considerable cellular stress via sulfite production, resulting in a decrease of the availability of the glutathione pathway's sulfur intermediates. The most limited effect was observed for the cystine supply, suggesting that the intracellular cysteine level is more controlled than that of methionine and sulfate. Using a combination of metabolomic profiling and genetic experiments, we revealed taurine and hypotaurine metabolism in yeast for the first time. On the basis of a phylogenetic study, we then demonstrated that this pathway was lost by some of the hemiascomycetous yeasts during evolution

Soda-lime glass behavior under laser shock

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