EgoPoser: Robust Real-Time Ego-Body Pose Estimation in Large Scenes

Full-body ego-pose estimation from head and hand poses alone has become an active area of research to power articulate avatar representation on headset-based platforms. However, existing methods over-rely on the confines of the motion-capture spaces in which datasets were recorded, while simultaneously assuming continuous capture of joint motions and uniform body dimensions. In this paper, we propose EgoPoser, which overcomes these limitations by 1) rethinking the input representation for headset-based ego-pose estimation and introducing a novel motion decomposition method that predicts full-body pose independent of global positions, 2) robustly modeling body pose from intermittent hand position and orientation tracking only when inside a headset's field of view, and 3) generalizing across various body sizes for different users. Our experiments show that EgoPoser outperforms state-of-the-art methods both qualitatively and quantitatively, while maintaining a high inference speed of over 600 fps. EgoPoser establishes a robust baseline for future work, where full-body pose estimation needs no longer rely on outside-in capture and can scale to large-scene environments

Hazardous doses of the herbicide imazamox in wild plant species and oilseed rape cultivars

Imidazolinones and crops resistant to these herbicides have successfully been introduced recently in some European countries. Imazamox has a high efficacy, moderate persistence and ecotoxicity, but data on hazardous doses (HD) in non-target plants and species sensitivity distributions (SSDs) are still scarce. To screen a larger variety of plant taxa in standardized vegetative vigor tests, 22 wild plant species and 14 oilseed rape (OSR) cultivars were sown into trays filled with a standard soil. When seedlings had reached the three-to-four leaf stage, plants were exposed to a single application of the herbicide Bolero® using a commercial pump sprayer. The five treatments corresponded to rates of 0 (control), 0.4, 4, 20 and 40 g/ha of imazamox with latter representing the recommended dose in Switzerland. Two weeks after the application, five plants per treatment were sub-sampled at random and visible injuries and fresh weights were recorded as endpoints for herbicidal effects. Dose-response curves and effective doses (EDs) were fitted using the drc package of the statistical software R and SSDs were obtained using ETX2.0. ED50 varied between 0.006 and 37 g/ha of the active ingredient in Nigella arvensis and Brassica rapa. Several dose-response curves indicated hormetic effects at a hundredth of the recommended field dose. In OSR, exposure to the field rate (40 g/ha) resulted in growth reductions between 28 and 97 % in the non imazamox-tolerant cultivars and in growth stimulations of up to 20 % in imazamox-tolerant cultivars. Responses were unrelated to leaf thickness, growth rates and the taxonomy of the tested species. Hazardous doses were 0.32 g/ha for HD5 and 3.9 g/ha for HD50 indicating that 50 % of the non-target plants would be affected at a tenth of the recommended dose. Based on general herbicide drift values the results suggest that potentially adverse effects may be expected up to a distance of 4 m offsite. Keywords: Clearfield, non-target plants, plant growth tests, plant functional typesSchädliche Dosen des Herbizids Imazamox bei verschiedenen Wildpflanzenarten und RapssortenImidazolinone und gegen diese Herbizide resistente Sorten einiger Kulturarten wurden in den letzten Jahren in einigen Europäischen Ländern erfolgreich eingeführt. Imazamox hat eine hohe Wirksamkeit, moderate Persistenz und Ökotoxizität, aber es gibt bislang nur wenige Informationen zu Schaddosen (hazardous doses, HD) in Nichtzielpflanzen und Art-Sensitivitäts-Spektren (species sensitivity distributions, SSDs). Um eine größere Anzahl von Pflanzenarten in standardisierten Wachstumstests zu überprüfen, wurden 22 Wildpflanzenarten und 14 Rapssorten in mit Standardboden gefüllten Schalen ausgesät. Bei Erreichung des Drei- bis Vierblattstadiums wurden die Pflanzen einmal mittels Pumpsprüher mit dem Herbizid Bolero® behandelt. Die fünf eingesetzten Behandlungen entsprachen den Dosen 0 (Kontrolle), 0.4, 4, 20 und 40 g AS/ha, wobei die letztere in der Schweiz die empfohlene Aufwandmenge darstellte. Zwei Wochen nach der Applikation wurden fünf Pflanzen pro Behandlung nach dem Zufallsprinzip geerntet, wobei sichtbare Schäden und Frischgewichte als Wirkkriterien betrachtet wurden. Dosis-Wirkungs-Kurven und effektive Dosen (EDs) wurden mit Hilfe des drc-Pakets mit der Statistik-Software R berechnet und SSDs wurden mittels ETX2.0 abgeleitet. Die ED50-Werte schwankten zwischen 0.006 und 37 g/ha der aktiven Substanz in Nigella arvensis und Brassica rapa. Viele der Dosis-Wirkungs-Beziehungen deuteten hormetische Effekte bei einem Hundertstel der empfohlenen Aufwandmenge an. Bei den nicht Imazamox-toleranten Rapssorten wurden bei der empfohlenen Aufwandmenge (40 g/ha) Wachstumsreduktionen zwischen 28 und 97 % beobachtet, während in den Imazamox-toleranten Sorten Wachstumsstimulationen von bis zu 20 % auftraten. Die beobachteten Effekte standen in keinem Zusammenhang mit der Blattdichte, den Wachstumsraten und der Taxonomie der überprüften Pflanzenarten. Die ermittelten Schaddosen betrugen 0.32 g/ha für HD5 und 3.9 g/ha für HD50, was darauf hindeutet, dass 50 % der Nichtzielarten bei einem Zehntel der empfohlenen Aufwandmenge beeinträchtigt würden. Wenn man die Abdrifteckwerte für Herbizidanwendungen zu Grunde legt, wären potenziell nachteilige Effekte bis zu einer Entfernung von 4 m zum Feldrand zu erwarten. Stichwörter: Clearfield, funktionelle Pflanzentypen, Nichtzielpflanzen, Pflanzenwachstumstest

Efficiency of 7.2% hypertonic saline hydroxyethyl starch 200/0.5 versus mannitol 15% in the treatment of increased intracranial pressure in neurosurgical patients – a randomized clinical trial [ISRCTN62699180]

INTRODUCTION: This prospective randomized clinical study investigated the efficacy and safety of 7.2% hypertonic saline hydroxyethyl starch 200/0.5 (7.2% NaCl/HES 200/0.5) in comparison with 15% mannitol in the treatment of increased intracranial pressure (ICP). METHODS: Forty neurosurgical patients at risk of increased ICP were randomized to receive either 7.2% NaCl/HES 200/0.5 or 15% mannitol at a defined infusion rate, which was stopped when ICP was < 15 mmHg. RESULTS: Of the 40 patients, 17 patients received 7.2% NaCl/HES 200/0.5 and 15 received mannitol 15%. In eight patients, ICP did not exceed 20 mmHg so treatment was not necessary. Both drugs decreased ICP below 15 mmHg (p < 0.0001); 7.2% NaCl/HES 200/0.5 within 6.0 (1.2–15.0) min (all results are presented as median (minimum-maximum range)) and mannitol within 8.7 (4.2–19.9) min (p < 0.0002). 7.2% NaCl/HES 200/0.5 caused a greater decrease in ICP than mannitol (57% vs 48%; p < 0.01). The cerebral perfusion pressure was increased from 60 (39–78) mmHg to 72 (54–85) mmHg by infusion with 7.2% NaCl/HES 200/0.5 (p < 0.0001) and from 61 (47–71) mmHg to 70 (50–79) mmHg with mannitol (p < 0.0001). The mean arterial pressure was increased by 3.7% during the infusion of 7.2% NaCl/HES 200/0.5 but was not altered by mannitol. There were no clinically relevant effects on electrolyte concentrations and osmolarity in the blood. The mean effective dose to achieve an ICP below 15 mmHg was 1.4 (0.3–3.1) ml/kg for 7.2% NaCl/HES 200/0.5 and 1.8 (0.45–6.5) ml/kg for mannitol (p < 0.05). CONCLUSION: 7.2% NaCl/HES 200/0.5 is more effective than mannitol 15% in the treatment of increased ICP. A dose of 1.4 ml/kg of 7.2% NaCl/HES 200/0.5 can be recommended as effective and safe. The advantage of 7.2% NaCl/HES 200/0.5 might be explained by local osmotic effects, because there were no clinically relevant differences in hemodynamic clinical chemistry parameters

How to Compare Fuzzers

Fuzzing is a key method to discover vulnerabilities in programs. Despite considerable progress in this area in the past years, measuring and comparing the effectiveness of fuzzers is still an open research question. In software testing, the gold standard for evaluating test quality is mutation analysis, assessing the ability of a test to detect synthetic bugs; if a set of tests fails to detect such mutations, it will also fail to detect real bugs. Mutation analysis subsumes various coverage measures and provides a large and diverse set of faults that can be arbitrarily hard to trigger and detect, thus preventing the problems of saturation and overfitting. Unfortunately, the cost of traditional mutation analysis is exorbitant for fuzzing, as mutations need independent evaluation. In this paper, we apply modern mutation analysis techniques that pool multiple mutations; allowing us, for the first time, to evaluate and compare fuzzers with mutation analysis. We introduce an evaluation bench for fuzzers and apply it to a number of popular fuzzers and subjects. In a comprehensive evaluation, we show how it allows us to assess fuzzer performance and measure the impact of improved techniques. While we find that today's fuzzers can detect only a small percentage of mutations, this should be seen as a challenge for future research -- notably in improving (1) detecting failures beyond generic crashes (2) triggering mutations (and thus faults).Comment: 13 pages, 4 figure

Proposal for Quantum Simulation via All-Optically Generated Tensor Network States

We devise an all-optical scheme for the generation of entangled multimode photonic states encoded in temporal modes of light. The scheme employs a nonlinear down-conversion process in an optical loop to generate one- and higher-dimensional tensor network states of light. We illustrate the principle with the generation of two different classes of entangled tensor network states and report on a variational algorithm to simulate the ground-state physics of many-body systems. We demonstrate that state-of-the-art optical devices are capable of determining the ground-state properties of the spin-1/2 Heisenberg model. Finally, implementations of the scheme are demonstrated to be robust against realistic losses and mode mismatch.Comment: 6 pages main text plus 6 pages Supplementary Material and many figures. Updated to published version. Comments welcom

Quantitative and Discrete Evolutionary Changes in the Egg-Laying Behavior of Single Drosophila Females

How a nervous system assembles and coordinates a suite of elementary behavioral steps into a complex behavior is not well understood. While often presented as a stereotyped sequence of events, even extensively studied behaviors such as fly courtship are rarely a strict repetition of the same steps in a predetermined sequence in time. We are focusing on oviposition, the act of laying an egg, in flies of the genus Drosophila to describe the elementary behavioral steps or microbehaviors that a single female fly undertakes prior to and during egg laying. We have analyzed the hierarchy and relationships in time of these microbehaviors in three closely related Drosophila species with divergent egg-laying preferences and uncovered cryptic differences in their behavioral patterns. Using high-speed imaging, we quantified in depth the oviposition behavior of single females of Drosophila suzukii, Drosophila biarmipes and Drosophila melanogaster in a novel behavioral assay. By computing transitions between microbehaviors, we identified a common ethogram structure underlying oviposition of all three species. Quantifying parameters such as relative time spent on a microbehavior and its average duration, however, revealed clear differences between species. In addition, we examined the temporal dynamics and probability of transitions to different microbehaviors relative to a central event of oviposition, ovipositor contact. Although the quantitative analysis highlights behavioral variability across flies, it reveals some interesting trends for each species in the mode of substrate sampling, as well as possible evolutionary differences. Larger datasets derived from automated video annotation will overcome this paucity of data in the future, and use the same framework to reappraise these observed differences. Our study reveals a common architecture to the oviposition ethogram of three Drosophila species, indicating its ancestral state. It also indicates that Drosophila suzukii’s behavior departs quantitatively and qualitatively from that of the outgroup species, in line with its known divergent ethology. Together, our results illustrate how a global shift in ethology breaks down in the quantitative reorganization of the elementary steps underlying a complex behavior

North Atlantic forcing of tropical Indian Ocean climate

Author Posting. © The Author(s), 2014. This is the author's version of the work. It is posted here by permission of Nature Publishing Group for personal use, not for redistribution. The definitive version was published in Nature 509 (2014): 76-80, doi:10.1038/nature13196.The response of the tropical climate in the Indian Ocean realm to abrupt climate change events in the North Atlantic Ocean is contentious. Repositioning of the intertropical convergence zone is thought to have been responsible for changes in tropical hydroclimate during North Atlantic cold spells1–5, but the dearth of high-resolution records outside the monsoon realm in the Indian Ocean precludes a full understanding of this remote relationship and its underlying mechanisms. Here we show that slowdowns of the Atlantic meridional overturning circulation during Heinrich stadials and the Younger Dryas stadial affected the tropical Indian Ocean hydroclimate through changes to the Hadley circulation including a southward shift in the rising branch (the intertropical convergence zone) and an overall weakening over the southern Indian Ocean. Our results are based on new, high-resolution sea surface temperature and seawater oxygen isotope records of well dated sedimentary archives from the tropical eastern Indian Ocean for the past 45,000 years, combined with climate model simulations of Atlantic circulation slowdown under Marine Isotope Stages 2 and 3 boundary conditions. Similar conditions in the east and west of the basin rule out a zonal dipole structure as the dominant forcing of the tropical Indian Ocean hydroclimate of millennial-scale events. Results from our simulations and proxy data suggest dry conditions in the northern Indian Ocean realm and wet and warm conditions in the southern realm during North Atlantic cold spells.This study was funded by the German Bundesministerium für Bildung und Forschung (grant 03G0189A) and the Deutsche Forschungsgemeinschaft (DFG grants HE3412/15-1 and STE1044/4-1, and the DFG Research Centre/Cluster of Excellence ‘The Ocean in the Earth System’). D.W.O. is funded by the US NSF, R.D.P.-H. is supported by Chilean FONDAP 15110009/ICM Nucleus NC120066.2014-10-3