Playable Environments: {V}ideo Manipulation in Space and Time

We present Playable Environments-a new representation for interactive video generation and manipulation in space and time. With a single image at inference time, our novel framework allows the user to move objects in 3D while generating a video by providing a sequence of desired actions. The actions are learnt in an unsupervised manner. The camera can be controlled to get the desired viewpoint. Our method builds an environment state for each frame, which can be manipulated by our proposed action mod-ule and decoded back to the image space with volumetric rendering. To support diverse appearances of objects, we extend neural radiance fields with style-based modulation. Our method trains on a collection of various monocular videos requiring only the estimated camera parameters and 2D object locations. To set a challenging benchmark, we in-troduce two large scale video datasets with significant cam-era movements. As evidenced by our experiments, playable environments enable several creative applications not at-tainable by prior video synthesis works, including playable 3D video generation, stylization and manipulation 1 1 willi-menapace.github.io/playable-environments-website

Mechanism for export of sediment-derived iron in an upwelling regime

Author Posting. © American Geophysical Union, 2012. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 39 (2012): L03601, doi:10.1029/2011GL050366.Model simulations performed with a three-dimensional, high-resolution, process study ocean model of eastern boundary upwelling systems are used to describe a mechanism that efficiently transports sediment-derived dissolved iron offshore in the subsurface through the bottom boundary layer (BBL) during downwelling-favorable wind events. In the model, sediment-derived iron accumulates in the BBL on the outer shelf when the winds are upwelling-favorable. When the wind reverses, the iron-laden BBL is mixed into the water column and transported offshore along isopycnals that intersect the bottom. Depending on the frequency of wind reversal, between 10–50% of the shelf sediment-derived iron flux is exported offshore through this previously unidentified subsurface pathway. If this mechanism operates on all coastal upwelling regimes, the global export of sediment-derived iron to the open ocean would be equivalent to ten times larger than the estimated source of dissolved iron from aerosols.NSF supported this work.2012-08-1

Do submesoscale frontal processes ventilate the oxygen minimum zone off Peru?

The Peruvian upwelling system encompasses the most intense and shallowest oxygen minimum zone (OMZ) in the ocean. This system shows pronounced submesoscale activity like filaments and fronts. We carried out glider-based observations off Peru during austral summer 2013 to investigate whether submesoscale frontal processes ventilate the Peruvian OMZ. We present observational evidence for the subduction of highly oxygenated surface water in a submesoscale cold filament. The subduction event ventilates the oxycline but does not reach OMZ core waters. In a regional submesoscale-permitting model we study the pathways of newly upwelled water. About 50% of upwelled virtual floats are subducted below the mixed layer within 5 days emphasizing a hitherto unrecognized importance of subduction for the ventilation of the Peruvian oxycline

Metabolic network alterations as a supportive biomarker in dementia with Lewy bodies with preserved dopamine transmission

Purpose Metabolic network analysis of FDG-PET utilizes an index of inter-regional correlation of resting state glucose metabolism and has been proven to provide complementary information regarding the disease process in parkinsonian syndromes. The goals of this study were (i) to evaluate pattern similarities of glucose metabolism and network connectivity in dementia with Lewy bodies (DLB) subjects with subthreshold dopaminergic loss compared to advanced disease stages and to (ii) investigate metabolic network alterations of FDG-PET for discrimination of patients with early DLB from other neurodegenerative disorders (Alzheimer’s disease, Parkinson’s disease, multiple system atrophy) at individual patient level via principal component analysis (PCA). Methods FDG-PETs of subjects with probable or possible DLB (n = 22) without significant dopamine deficiency (z-score < 2 in putamen binding loss on DaT-SPECT compared to healthy controls (HC)) were scaled by global-mean, prior to volume-of-interest-based analyses of relative glucose metabolism. Single region metabolic changes and network connectivity changes were compared against HC (n = 23) and against DLB subjects with significant dopamine deficiency (n = 86). PCA was applied to test discrimination of patients with DLB from disease controls (n = 101) at individual patient level. Results Similar patterns of hypo- (parietal- and occipital cortex) and hypermetabolism (basal ganglia, limbic system, motor cortices) were observed in DLB patients with and without significant dopamine deficiency when compared to HC. Metabolic connectivity alterations correlated between DLB patients with and without significant dopamine deficiency (R2 = 0.597, p < 0.01). A PCA trained by DLB patients with dopamine deficiency and HC discriminated DLB patients without significant dopaminergic loss from other neurodegenerative parkinsonian disorders at individual patient level (area-under-the-curve (AUC): 0.912). Conclusion Disease-specific patterns of altered glucose metabolism and altered metabolic networks are present in DLB subjects without significant dopaminergic loss. Metabolic network alterations in FDG-PET can act as a supporting biomarker in the subgroup of DLB patients without significant dopaminergic loss at symptoms onset

Explainability for regression CNN in fetal head circumference estimation from ultrasound images

International audienceThe measurement of fetal head circumference (HC) is performed throughout the pregnancy to monitor fetus growth using ultra-sound (US) images. Recently, methods that directly predict biometric from images, instead of resorting to segmentation, have emerged. In our previous work, we have proposed such method, based on a regression con-volutional neural network (CNN). If deep learning methods are the gold standard in most image processing tasks, they are often considered as black boxes and fails to provide interpretable decisions. In this paper, we investigate various saliency maps methods, to leverage their ability at explaining the predicted value of the regression CNN. Since saliency maps methods have been developed for classification CNN mostly, we provide an interpretation for regression saliency maps, as well as an adaptation of a perturbation-based quantitative evaluation of explanations methods. Results obtained on a public dataset of ultrasound images show that some saliency maps indeed exhibit the head contour as the most relevant features to assess the head circumference and also that the map quality depends on the backbone architecture and whether the prediction error is low or high

First report of a Messinian coralgal facies in a terrigenous setting of Central Apennines (Italy) and its palaeogeographic significance

The upper Miocene dominantly terrigenous succession cropping out at Monte San Fabrizio (Simbruini Mts.) shows peculiar, previously unreported bio‐sedimentological features, which bring fresh elements in a regional palaeogeographic/palaeotectonic key. Overlying the regional foredeep succession, an array of different lithofacies either form mappable outcrops or occur as clasts, remarkably not referable to any stratigraphic units already known in the Central Apennines. These lithologies, which include coral‐bearing siliciclastic sediments, mixed carbonate/siliciclastic deposits with benthic macrofaunas, rhodalgal facies, and conglomerates, essentially made of Mesozoic pelagic lithoclasts, are here grouped in a comprehensive informal unit, called Monte San Fabrizio Unit (MSFU). The most striking feature of the MSFU is a coralgal facies characterized by the occurrence of zooxanthellate (z) corals (Porites and Siderastrea crenulata). While the age of these deposits is not directly determinable due to the lack of biostratigraphic markers, their composition and field relationships clearly place their origin within a late‐orogenic setting: only the uplift, subaerial exposure, and erosion of large portions of the pre‐orogenic stratigraphy, also belonging to different geological domains, and subsequent sediment transport by rivers, can account for the heterogeneous composition of the conglomerates. Their sedimentological characters (i.e., shape and size of the clasts) suggest reworking of the pebbles in a shore environment. A shallow marine photic environment is confirmed by the presence of z‐corals, red algae, and abundant macrofauna. The occurrence of Porites and Siderastrea crenulata represents the first occurrence of corals subsequent to the drowning of the bryozoan limestone carbonate factory, being the youngest occurrence of corals in the Central Apennines and the first ever post‐Burdigalian z‐corals described in the region. This also constrains the age of the MSFU as early–middle (pre‐evaporitic) Messinian, due to the almost total demise of z‐corals known in the Mediterranean in response to the Messinian Salinity Crisis. In conclusion, sedimentology, palaeobiology, and field geology all point to a shallow‐water environment, close to a shoreline, for the MSFU. This unit can be interpreted as representing the vestiges of an ephemeral depositional environment, such as a small wedge‐top basin, an evidence that this portion of the Apennine chain was already structured in the early–middle Messinian