@inproceedings{8188, abstract = {A natural approach to generative modeling of videos is to represent them as a composition of moving objects. Recent works model a set of 2D sprites over a slowly-varying background, but without considering the underlying 3D scene that gives rise to them. We instead propose to model a video as the view seen while moving through a scene with multiple 3D objects and a 3D background. Our model is trained from monocular videos without any supervision, yet learns to generate coherent 3D scenes containing several moving objects. We conduct detailed experiments on two datasets, going beyond the visual complexity supported by state-of-the-art generative approaches. We evaluate our method on depth-prediction and 3D object detection---tasks which cannot be addressed by those earlier works---and show it out-performs them even on 2D instance segmentation and tracking.}, author = {Henderson, Paul M and Lampert, Christoph}, booktitle = {34th Conference on Neural Information Processing Systems}, isbn = {9781713829546}, location = {Vancouver, Canada}, pages = {3106–3117}, publisher = {Neural Information Processing Systems Foundation}, title = {{Unsupervised object-centric video generation and decomposition in 3D}}, volume = {33}, year = {2020}, } @article{8189, abstract = {Direct ethanol fuel cells (DEFCs) show a huge potential to power future electric vehicles and portable electronics, but their deployment is currently limited by the unavailability of proper electrocatalysis for the ethanol oxidation reaction (EOR). In this work, we engineer a new electrocatalyst by incorporating phosphorous into a palladium-tin alloy and demonstrate a significant performance improvement toward EOR. We first detail a synthetic method to produce Pd2Sn:P nanocrystals that incorporate 35% of phosphorus. These nanoparticles are supported on carbon black and tested for EOR. Pd2Sn:P/C catalysts exhibit mass current densities up to 5.03 A mgPd−1, well above those of Pd2Sn/C, PdP2/C and Pd/C reference catalysts. Furthermore, a twofold lower Tafel slope and a much longer durability are revealed for the Pd2Sn:P/C catalyst compared with Pd/C. The performance improvement is rationalized with the aid of density functional theory (DFT) calculations considering different phosphorous chemical environments. Depending on its oxidation state, surface phosphorus introduces sites with low energy OH− adsorption and/or strongly influences the electronic structure of palladium and tin to facilitate the oxidation of the acetyl to acetic acid, which is considered the EOR rate limiting step. DFT calculations also points out that the durability improvement of Pd2Sn:P/C catalyst is associated to the promotion of OH adsorption that accelerates the oxidation of intermediate poisoning COads, reactivating the catalyst surface.}, author = {Yu, Xiaoting and Liu, Junfeng and Li, Junshan and Luo, Zhishan and Zuo, Yong and Xing, Congcong and Llorca, Jordi and Nasiou, Déspina and Arbiol, Jordi and Pan, Kai and Kleinhanns, Tobias and Xie, Ying and Cabot, Andreu}, issn = {2211-2855}, journal = {Nano Energy}, number = {11}, publisher = {Elsevier}, title = {{Phosphorous incorporation in Pd2Sn alloys for electrocatalytic ethanol oxidation}}, doi = {10.1016/j.nanoen.2020.105116}, volume = {77}, year = {2020}, } @inproceedings{8191, abstract = {There has been a significant amount of research on hardware and software support for efficient concurrent data structures; yet, the question of how to build correct, simple, and scalable data structures has not yet been definitively settled. In this paper, we revisit this question from a minimalist perspective, and ask: what is the smallest amount of synchronization required for correct and efficient concurrent search data structures, and how could this minimal synchronization support be provided in hardware? To address these questions, we introduce memory tagging, a simple hardware mechanism which enables the programmer to "tag" a dynamic set of memory locations, at cache-line granularity, and later validate whether the memory has been concurrently modified, with the possibility of updating one of the underlying locations atomically if validation succeeds. We provide several examples showing that this mechanism can enable fast and arguably simple concurrent data structure designs, such as lists, binary search trees, balanced search trees, range queries, and Software Transactional Memory (STM) implementations. We provide an implementation of memory tags in the Graphite multi-core simulator, showing that the mechanism can be implemented entirely at the level of L1 cache, and that it can enable non-trivial speedups versus existing implementations of the above data structures.}, author = {Alistarh, Dan-Adrian and Brown, Trevor A and Singhal, Nandini}, booktitle = {Annual ACM Symposium on Parallelism in Algorithms and Architectures}, isbn = {9781450369350}, location = {Virtual Event, United States}, number = {7}, pages = {37--49}, publisher = {Association for Computing Machinery}, title = {{Memory tagging: Minimalist synchronization for scalable concurrent data structures}}, doi = {10.1145/3350755.3400213}, year = {2020}, } @article{8199, abstract = {We investigate a mechanism to transiently stabilize topological phenomena in long-lived quasi-steady states of isolated quantum many-body systems driven at low frequencies. We obtain an analytical bound for the lifetime of the quasi-steady states which is exponentially large in the inverse driving frequency. Within this lifetime, the quasi-steady state is characterized by maximum entropy subject to the constraint of fixed number of particles in the system's Floquet-Bloch bands. In such a state, all the non-universal properties of these bands are washed out, hence only the topological properties persist.}, author = {Gulden, Tobias and Berg, Erez and Rudner, Mark Spencer and Lindner, Netanel}, issn = {2542-4653}, journal = {SciPost Physics}, publisher = {SciPost Foundation}, title = {{Exponentially long lifetime of universal quasi-steady states in topological Floquet pumps}}, doi = {10.21468/scipostphys.9.1.015}, volume = {9}, year = {2020}, } @article{8203, abstract = {Using inelastic cotunneling spectroscopy we observe a zero field splitting within the spin triplet manifold of Ge hut wire quantum dots. The states with spin ±1 in the confinement direction are energetically favored by up to 55 μeV compared to the spin 0 triplet state because of the strong spin–orbit coupling. The reported effect should be observable in a broad class of strongly confined hole quantum-dot systems and might need to be considered when operating hole spin qubits.}, author = {Katsaros, Georgios and Kukucka, Josip and Vukušić, Lada and Watzinger, Hannes and Gao, Fei and Wang, Ting and Zhang, Jian-Jun and Held, Karsten}, issn = {1530-6992}, journal = {Nano Letters}, number = {7}, pages = {5201--5206}, publisher = {American Chemical Society}, title = {{Zero field splitting of heavy-hole states in quantum dots}}, doi = {10.1021/acs.nanolett.0c01466}, volume = {20}, year = {2020}, } @article{8225, abstract = {Birch pollen allergy is among the most prevalent pollen allergies in Northern and Central Europe. This IgE-mediated disease can be treated with allergen immunotherapy (AIT), which typically gives rise to IgG antibodies inducing tolerance. Although the main mechanisms of allergen immunotherapy (AIT) are known, questions regarding possible Fc-mediated effects of IgG antibodies remain unanswered. This can mainly be attributed to the unavailability of appropriate tools, i.e., well-characterised recombinant antibodies (rAbs). We hereby aimed at providing human rAbs of several classes for mechanistic studies and as possible candidates for passive immunotherapy. We engineered IgE, IgG1, and IgG4 sharing the same variable region against the major birch pollen allergen Bet v 1 using Polymerase Incomplete Primer Extension (PIPE) cloning. We tested IgE functionality and IgG blocking capabilities using appropriate model cell lines. In vitro studies showed IgE engagement with FcεRI and CD23 and Bet v 1-dependent degranulation. Overall, we hereby present fully functional, human IgE, IgG1, and IgG4 sharing the same variable region against Bet v 1 and showcase possible applications in first mechanistic studies. Furthermore, our IgG antibodies might be useful candidates for passive immunotherapy of birch pollen allergy.}, author = {Köhler, Verena K. and Crescioli, Silvia and Fazekas-Singer, Judit and Bax, Heather J. and Hofer, Gerhard and Pranger, Christina L. and Hufnagl, Karin and Bianchini, Rodolfo and Flicker, Sabine and Keller, Walter and Karagiannis, Sophia N. and Jensen-Jarolim, Erika}, issn = {1422-0067}, journal = {International Journal of Molecular Sciences}, number = {16}, publisher = {MDPI}, title = {{Filling the antibody pipeline in allergy: PIPE cloning of IgE, IgG1 and IgG4 against the major birch pollen allergen Bet v 1}}, doi = {10.3390/ijms21165693}, volume = {21}, year = {2020}, } @article{8226, author = {Gotovina, Jelena and Bianchini, Rodolfo and Fazekas-Singer, Judit and Herrmann, Ina and Pellizzari, Giulia and Haidl, Ian D. and Hufnagl, Karin and Karagiannis, Sophia N. and Marshall, Jean S. and Jensen‐Jarolim, Erika}, issn = {0105-4538}, journal = {Allergy}, publisher = {Wiley}, title = {{Epinephrine drives human M2a allergic macrophages to a regulatory phenotype reducing mast cell degranulation in vitro}}, doi = {10.1111/all.14299}, year = {2020}, } @misc{8254, abstract = {Here are the research data underlying the publication "Estimating inbreeding and its effects in a long-term study of snapdragons (Antirrhinum majus)". Further information are summed up in the README document. The files for this record have been updated and are now found in the linked DOI https://doi.org/10.15479/AT:ISTA:9192.}, author = {Arathoon, Louise S}, publisher = {Institute of Science and Technology Austria}, title = {{Estimating inbreeding and its effects in a long-term study of snapdragons (Antirrhinum majus)}}, doi = {10.15479/AT:ISTA:8254}, year = {2020}, } @article{8261, abstract = {Dentate gyrus granule cells (GCs) connect the entorhinal cortex to the hippocampal CA3 region, but how they process spatial information remains enigmatic. To examine the role of GCs in spatial coding, we measured excitatory postsynaptic potentials (EPSPs) and action potentials (APs) in head-fixed mice running on a linear belt. Intracellular recording from morphologically identified GCs revealed that most cells were active, but activity level varied over a wide range. Whereas only ∼5% of GCs showed spatially tuned spiking, ∼50% received spatially tuned input. Thus, the GC population broadly encodes spatial information, but only a subset relays this information to the CA3 network. Fourier analysis indicated that GCs received conjunctive place-grid-like synaptic input, suggesting code conversion in single neurons. GC firing was correlated with dendritic complexity and intrinsic excitability, but not extrinsic excitatory input or dendritic cable properties. Thus, functional maturation may control input-output transformation and spatial code conversion.}, author = {Zhang, Xiaomin and Schlögl, Alois and Jonas, Peter M}, issn = {0896-6273}, journal = {Neuron}, number = {6}, pages = {1212--1225}, publisher = {Elsevier}, title = {{Selective routing of spatial information flow from input to output in hippocampal granule cells}}, doi = {10.1016/j.neuron.2020.07.006}, volume = {107}, year = {2020}, } @article{8268, abstract = {Modern scientific instruments produce vast amounts of data, which can overwhelm the processing ability of computer systems. Lossy compression of data is an intriguing solution, but comes with its own drawbacks, such as potential signal loss, and the need for careful optimization of the compression ratio. In this work, we focus on a setting where this problem is especially acute: compressive sensing frameworks for interferometry and medical imaging. We ask the following question: can the precision of the data representation be lowered for all inputs, with recovery guarantees and practical performance Our first contribution is a theoretical analysis of the normalized Iterative Hard Thresholding (IHT) algorithm when all input data, meaning both the measurement matrix and the observation vector are quantized aggressively. We present a variant of low precision normalized IHT that, under mild conditions, can still provide recovery guarantees. The second contribution is the application of our quantization framework to radio astronomy and magnetic resonance imaging. We show that lowering the precision of the data can significantly accelerate image recovery. We evaluate our approach on telescope data and samples of brain images using CPU and FPGA implementations achieving up to a 9x speedup with negligible loss of recovery quality.}, author = {Gurel, Nezihe Merve and Kara, Kaan and Stojanov, Alen and Smith, Tyler and Lemmin, Thomas and Alistarh, Dan-Adrian and Puschel, Markus and Zhang, Ce}, issn = {1941-0476}, journal = {IEEE Transactions on Signal Processing}, pages = {4268--4282}, publisher = {IEEE}, title = {{Compressive sensing using iterative hard thresholding with low precision data representation: Theory and applications}}, doi = {10.1109/TSP.2020.3010355}, volume = {68}, year = {2020}, } @article{8271, author = {He, Peng and Zhang, Yuzhou and Xiao, Guanghui}, issn = {1752-9867}, journal = {Molecular Plant}, number = {9}, pages = {1238--1240}, publisher = {Elsevier}, title = {{Origin of a subgenome and genome evolution of allotetraploid cotton species}}, doi = {10.1016/j.molp.2020.07.006}, volume = {13}, year = {2020}, } @article{8285, abstract = {We demonstrate the utility of optical cavity generated spin-squeezed states in free space atomic fountain clocks in ensembles of 390 000 87Rb atoms. Fluorescence imaging, correlated to an initial quantum nondemolition measurement, is used for population spectroscopy after the atoms are released from a confining lattice. For a free fall time of 4 milliseconds, we resolve a single-shot phase sensitivity of 814(61) microradians, which is 5.8(0.6) decibels (dB) below the quantum projection limit. We observe that this squeezing is preserved as the cloud expands to a roughly 200  μm radius and falls roughly 300  μm in free space. Ramsey spectroscopy with 240 000 atoms at a 3.6 ms Ramsey time results in a single-shot fractional frequency stability of 8.4(0.2)×10−12, 3.8(0.2) dB below the quantum projection limit. The sensitivity and stability are limited by the technical noise in the fluorescence detection protocol and the microwave system, respectively.}, author = {Malia, Benjamin K. and Martínez-Rincón, Julián and Wu, Yunfan and Hosten, Onur and Kasevich, Mark A.}, issn = {1079-7114}, journal = {Physical Review Letters}, number = {4}, publisher = {American Physical Society}, title = {{Free space Ramsey spectroscopy in rubidium with noise below the quantum projection limit}}, doi = {10.1103/PhysRevLett.125.043202}, volume = {125}, year = {2020}, } @misc{8294, abstract = {Automated root growth analysis and tracking of root tips. }, author = {Hauschild, Robert}, publisher = {IST Austria}, title = {{RGtracker}}, doi = {10.15479/AT:ISTA:8294}, year = {2020}, } @unpublished{8307, abstract = {Classic Byzantine fault-tolerant consensus protocols forfeit liveness in the face of asynchrony in order to preserve safety, whereas most deployed blockchain protocols forfeit safety in order to remain live. In this work, we achieve the best of both worlds by proposing a novel abstractions called the finality gadget. A finality gadget allows for transactions to always optimistically commit but informs the clients that these transactions might be unsafe. As a result, a blockchain can execute transactions optimistically and only commit them after they have been sufficiently and provably audited. In this work, we formally model the finality gadget abstraction, prove that it is impossible to solve it deterministically in full asynchrony (even though it is stronger than consensus) and provide a partially synchronous protocol which is currently securing a major blockchain. This way we show that the protocol designer can decouple safety and liveness in order to speed up recovery from failures. We believe that there can be other types of finality gadgets that provide weaker safety (e.g., probabilistic) in order to gain more efficiency and this can depend on the probability that the network is not in synchrony.}, author = {Stewart, Alistair and Kokoris Kogias, Eleftherios}, booktitle = {arXiv}, title = {{GRANDPA: A Byzantine finality gadget}}, doi = {10.48550/arXiv.2007.01560}, year = {2020}, } @article{8319, abstract = {We demonstrate that releasing atoms into free space from an optical lattice does not deteriorate cavity-generated spin squeezing for metrological purposes. In this work, an ensemble of 500000 spin-squeezed atoms in a high-finesse optical cavity with near-uniform atom-cavity coupling is prepared, released into free space, recaptured in the cavity, and probed. Up to ∼10 dB of metrologically relevant squeezing is retrieved for 700μs free-fall times, and decaying levels of squeezing are realized for up to 3 ms free-fall times. The degradation of squeezing results from loss of atom-cavity coupling homogeneity between the initial squeezed state generation and final collective state readout. A theoretical model is developed to quantify this degradation and this model is experimentally validated.}, author = {Wu, Yunfan and Krishnakumar, Rajiv and Martínez-Rincón, Julián and Malia, Benjamin K. and Hosten, Onur and Kasevich, Mark A.}, issn = {2469-9934}, journal = {Physical Review A}, number = {1}, publisher = {American Physical Society}, title = {{Retrieval of cavity-generated atomic spin squeezing after free-space release}}, doi = {10.1103/PhysRevA.102.012224}, volume = {102}, year = {2020}, } @article{8320, abstract = {The genetic code is considered to use five nucleic bases (adenine, guanine, cytosine, thymine and uracil), which form two pairs for encoding information in DNA and two pairs for encoding information in RNA. Nevertheless, in recent years several artificial base pairs have been developed in attempts to expand the genetic code. Employment of these additional base pairs increases the information capacity and variety of DNA sequences, and provides a platform for the site-specific, enzymatic incorporation of extra functional components into DNA and RNA. As a result, of the development of such expanded systems, many artificial base pairs have been synthesized and tested under various conditions. Following many stages of enhancement, unnatural base pairs have been modified to eliminate their weak points, qualifying them for specific research needs. Moreover, the first attempts to create a semi-synthetic organism containing DNA with unnatural base pairs seem to have been successful. This further extends the possible applications of these kinds of pairs. Herein, we describe the most significant qualities of unnatural base pairs and their actual applications.}, author = {Mukba, S. A. and Vlasov, Petr and Kolosov, P. M. and Shuvalova, E. Y. and Egorova, T. V. and Alkalaeva, E. Z.}, issn = {1608-3245}, journal = {Molecular Biology}, number = {4}, pages = {475--484}, publisher = {Springer Nature}, title = {{Expanding the genetic code: Unnatural base pairs in biological systems}}, doi = {10.1134/S0026893320040111}, volume = {54}, year = {2020}, } @article{8321, abstract = {The genetic code is considered to use five nucleic bases (adenine, guanine, cytosine, thymine and uracil), which form two pairs for encoding information in DNA and two pairs for encoding information in RNA. Nevertheless, in recent years several artificial base pairs have been developed in attempts to expand the genetic code. Employment of these additional base pairs increases the information capacity and variety of DNA sequences, and provides a platform for the site-specific, enzymatic incorporation of extra functional components into DNA and RNA. As a result, of the development of such expanded systems, many artificial base pairs have been synthesized and tested under various conditions. Following many stages of enhancement, unnatural base pairs have been modified to eliminate their weak points, qualifying them for specific research needs. Moreover, the first attempts to create a semi-synthetic organism containing DNA with unnatural base pairs seem to have been successful. This further extends the possible applications of these kinds of pairs. Herein, we describe the most significant qualities of unnatural base pairs and their actual applications.}, author = {Mukba, S. A. and Vlasov, Petr and Kolosov, P. M. and Shuvalova, E. Y. and Egorova, T. V. and Alkalaeva, E. Z.}, issn = {0026-8984}, journal = {Molekuliarnaia biologiia}, number = {4}, pages = {531--541}, publisher = {Russian Academy of Sciences}, title = {{Expanding the genetic code: Unnatural base pairs in biological systems}}, doi = {10.31857/S0026898420040126}, volume = {54}, year = {2020}, } @article{8323, author = {Pach, János}, issn = {14320444}, journal = {Discrete and Computational Geometry}, pages = {571--574}, publisher = {Springer Nature}, title = {{A farewell to Ricky Pollack}}, doi = {10.1007/s00454-020-00237-5}, volume = {64}, year = {2020}, } @inproceedings{8324, abstract = {The notion of program sensitivity (aka Lipschitz continuity) specifies that changes in the program input result in proportional changes to the program output. For probabilistic programs the notion is naturally extended to expected sensitivity. A previous approach develops a relational program logic framework for proving expected sensitivity of probabilistic while loops, where the number of iterations is fixed and bounded. In this work, we consider probabilistic while loops where the number of iterations is not fixed, but randomized and depends on the initial input values. We present a sound approach for proving expected sensitivity of such programs. Our sound approach is martingale-based and can be automated through existing martingale-synthesis algorithms. Furthermore, our approach is compositional for sequential composition of while loops under a mild side condition. We demonstrate the effectiveness of our approach on several classical examples from Gambler's Ruin, stochastic hybrid systems and stochastic gradient descent. We also present experimental results showing that our automated approach can handle various probabilistic programs in the literature.}, author = {Wang, Peixin and Fu, Hongfei and Chatterjee, Krishnendu and Deng, Yuxin and Xu, Ming}, booktitle = {Proceedings of the ACM on Programming Languages}, issn = {2475-1421}, number = {POPL}, publisher = {ACM}, title = {{Proving expected sensitivity of probabilistic programs with randomized variable-dependent termination time}}, doi = {10.1145/3371093}, volume = {4}, year = {2020}, } @article{8325, abstract = {Let 𝐹:ℤ2→ℤ be the pointwise minimum of several linear functions. The theory of smoothing allows us to prove that under certain conditions there exists the pointwise minimal function among all integer-valued superharmonic functions coinciding with F “at infinity”. We develop such a theory to prove existence of so-called solitons (or strings) in a sandpile model, studied by S. Caracciolo, G. Paoletti, and A. Sportiello. Thus we made a step towards understanding the phenomena of the identity in the sandpile group for planar domains where solitons appear according to experiments. We prove that sandpile states, defined using our smoothing procedure, move changeless when we apply the wave operator (that is why we call them solitons), and can interact, forming triads and nodes. }, author = {Kalinin, Nikita and Shkolnikov, Mikhail}, issn = {1432-0916}, journal = {Communications in Mathematical Physics}, number = {9}, pages = {1649--1675}, publisher = {Springer Nature}, title = {{Sandpile solitons via smoothing of superharmonic functions}}, doi = {10.1007/s00220-020-03828-8}, volume = {378}, year = {2020}, }