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

Automatic Assessment and Learning of Robot Social Abilities

One of the key challenges of current state-of-the-art robotic deployments in public spaces, where the robot is supposed to interact with humans, is the generation of behaviors that are engaging for the users. Eliciting engagement during an interaction, and maintaining it after the initial phase of the interaction, is still an issue to be overcome. There is evidence that engagement in learning activities is higher in the presence of a robot, particularly if novel [1], but after the initial engagement state, long and non-interactive behaviors are detrimental to the continued engagement of the users [5, 16]. Overcoming this limitation requires to design robots with enhanced social abilities that go past monolithic behaviours and introduces in-situ learning and adaptation to the specific users and situations. To do so, the robot must have the ability to perceive the state of the humans participating in the interaction and use this feedback for the selection of its own actions over time [27]

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

The Hettangian corals of the Isle of Skye (Scotland): An opportunity to better understand the palaeoenvironmental conditions during the aftermath of the Triassic-Jurassic boundary crisis

International audienceAt Ob Lusa (Isle of Skye, Scotland), six distinct coral beds were observed in a modern outcrop where a Hettangian succession is exposed. The coral associations are monogenic, belonging to Lepidophyllia, a massive cerioid genus. The lowest bed has relatively well-developed colonies that form small bioconstructions, whereas the other beds have small and dispersed colonies that are completely drowned in the matrix. Their morphology and size can vary, but the general growth fabric is dominated by platy colonies. This type of growth fabric is defined as a platestone. The most surprising characteristic of these specimens, especially for the platy corals, is their growth pattern; many samples do not exhibit the classical growth polarity because they are bifacial. Geochemical analyses (δ180, δ13C) were conducted on oyster shells that were associated with the corals. The results indicate that the mean palaeotemperature was approximately 22 °C. Sedimentological analysis revealed shallow settings where the hydrodynamic energy and siliciclastic inputs fluctuated. The general faunal assemblage of the outcrop had low diversity and was mainly composed of allochthonous bioclasts. The corals at Ob Lusa clearly did not live under ideal environmental conditions for the development of corals