@article{6835, abstract = {We derive the Hasse principle and weak approximation for fibrations of certain varieties in the spirit of work by Colliot-Thélène–Sansuc and Harpaz–Skorobogatov–Wittenberg. Our varieties are defined through polynomials in many variables and part of our work is devoted to establishing Schinzel's hypothesis for polynomials of this kind. This last part is achieved by using arguments behind Birch's well-known result regarding the Hasse principle for complete intersections with the notable difference that we prove our result in 50% fewer variables than in the classical Birch setting. We also study the problem of square-free values of an integer polynomial with 66.6% fewer variables than in the Birch setting.}, author = {Destagnol, Kevin N and Sofos, Efthymios}, issn = {0007-4497}, journal = {Bulletin des Sciences Mathematiques}, number = {11}, publisher = {Elsevier}, title = {{Rational points and prime values of polynomials in moderately many variables}}, doi = {10.1016/j.bulsci.2019.102794}, volume = {156}, year = {2019}, } @article{175, abstract = {An upper bound sieve for rational points on suitable varieties isdeveloped, together with applications tocounting rational points in thin sets,to local solubility in families, and to the notion of “friable” rational pointswith respect to divisors. In the special case of quadrics, sharper estimates areobtained by developing a version of the Selberg sieve for rational points.}, author = {Browning, Timothy D and Loughran, Daniel}, issn = {1088-6850}, journal = {Transactions of the American Mathematical Society}, number = {8}, pages = {5757--5785}, publisher = {American Mathematical Society}, title = {{Sieving rational points on varieties}}, doi = {10.1090/tran/7514}, volume = {371}, year = {2019}, } @article{6620, abstract = {This paper establishes an asymptotic formula with a power-saving error term for the number of rational points of bounded height on the singular cubic surface of ℙ3ℚ given by the following equation 𝑥0(𝑥21+𝑥22)−𝑥33=0 in agreement with the Manin-Peyre conjectures. }, author = {De La Bretèche, Régis and Destagnol, Kevin N and Liu, Jianya and Wu, Jie and Zhao, Yongqiang}, issn = {1674-7283}, journal = {Science China Mathematics}, number = {12}, pages = {2435–2446}, publisher = {Springer}, title = {{On a certain non-split cubic surface}}, doi = {10.1007/s11425-018-9543-8}, volume = {62}, year = {2019}, } @article{22582, abstract = {Rising atmospheric carbon dioxide concentration should stimulate biomass production directly via biochemical stimulation of carbon assimilation, and indirectly via water savings caused by increased plant water-use efficiency. Because of these water savings, the CO2 fertilization effect (CFE) should be stronger at drier sites, yet large differences among experiments in grassland biomass response to elevated CO2 appear to be unrelated to annual precipitation, preventing useful generalizations. Here, we show that, as predicted, the impact of elevated CO2 on biomass production in 19 globally distributed temperate grassland experiments reduces as mean precipitation in seasons other than spring increases, but that it rises unexpectedly as mean spring precipitation increases. Moreover, because sites with high spring precipitation also tend to have high precipitation at other times, these effects of spring and non-spring precipitation on the CO2 response offset each other, constraining the response of ecosystem productivity to rising CO2. This explains why previous analyses were unable to discern a reliable trend between site dryness and the CFE. Thus, the CFE in temperate grasslands worldwide will be constrained by their natural rainfall seasonality such that the stimulation of biomass by rising CO2 could be substantially less than anticipated.}, author = {Hovenden, Mark J. and Leuzinger, Sebastian and Newton, Paul C. D. and Fletcher, Andrew and Fatichi, Simone and Lüscher, Andreas and Reich, Peter B. and Andresen, Louise C. and Beier, Claus and Blumenthal, Dana M. and Chiariello, Nona R. and Dukes, Jeffrey S. and Kellner, Juliane and Hofmockel, Kirsten and Niklaus, Pascal A. and Song, Jian and Wan, Shiqiang and Classen, Aimée T. and Langley, J. Adam}, issn = {2055-0278}, journal = {Nature Plants}, number = {2}, pages = {167--173}, publisher = {Springer Nature}, title = {{Globally consistent influences of seasonal precipitation limit grassland biomass response to elevated CO2}}, doi = {10.1038/s41477-018-0356-x}, volume = {5}, year = {2019}, } @article{22576, abstract = {The hydrological and biogeochemical response of rivers carries information about solute sources, pathways, and transformations in the catchment. We investigate long-term water quality data of 11 Swiss catchments with the objective to discern the influence of major catchment characteristics and anthropic activities on delivery of solutes in stream water. Magnitude, trends, and seasonality of water quality samplings of different solutes are evaluated and compared across catchments. Subsequently, the empirical dependence between concentration and discharge is used to classify the solute behaviors. While the anthropogenic impacts are clearly detectable in the concentration of certain solutes (i.e., Na+, Cl−, NO3, DRP), the influence of single catchment characteristics such as geology (e.g., on Ca2+ and H4SiO4), topography (e.g., on DOC, TOC, and TP), and size (e.g., on DOC and TOC) is only sometimes visible, which is also because of the limited sample size and the spatial heterogeneity within catchments. Solute variability in time is generally smaller than discharge variability and the most significant trends in time are due to temporal variations of anthropogenic rather than natural forcing. The majority of solutes show dilution with increasing discharge, especially geogenic species, while sediment-bonded solutes (e.g., total phosphorous and organic carbon species) show higher concentrations with increasing discharge. Both natural and anthropogenic factors affect the biogeochemical response of streams, and, while the majority of solutes show identifiable behaviors in individual catchments, only a minority of behaviors can be generalized across the 11 catchments that exhibit different natural, climatic, and anthropogenic features.}, author = {Botter, Martina and Burlando, Paolo and Fatichi, Simone}, issn = {1607-7938}, journal = {Hydrology and Earth System Sciences}, number = {4}, pages = {1885--1904}, publisher = {Copernicus Publications}, title = {{Anthropogenic and catchment characteristic signatures in the water quality of Swiss rivers: a quantitative assessment}}, doi = {10.5194/hess-23-1885-2019}, volume = {23}, year = {2019}, } @unpublished{8304, abstract = {Enabling secure communication across distributed systems is usually studied under the assumption of trust between the different systems and an external adversary trying to compromise the messages. With the appearance of distributed ledgers or blockchains, numerous protocols have emerged, which attempt to achieve trustless communication between distrusting ledgers and participants. Cross-chain communication (CCC) thereby plays a fundamental role in cryptocurrency exchanges, sharding, bootstrapping of new and feature-extension of existing distributed ledgers. Unfortunately, existing proposals are designed ad-hoc for specific use-cases, making it hard to gain confidence on their correctness and composability. We provide the first systematic exposition of protocols for CCC. First, we formalize the underlying research problem and show that CCC is impossible without a trusted third party, contrary to common beliefs in the blockchain community. We then develop a framework to evaluate existing and to design new cross-chain protocols. The framework is based on the use case, the trust model, and the security assumptions of interlinked blockchains. Finally, we identify security and privacy challenges faced by protocols in the cross-chain setting. This Systematization of Knowledge (SoK) offers a comprehensive guide for designing protocols bridging the numerous distributed ledgers available today. It aims to facilitate clearer communication between academia and industry in the field.}, author = {Zamyatin, Alexei and Al-Bassam, Mustafa and Zindros, Dionysis and Kokoris Kogias, Eleftherios and Moreno-Sanchez, Pedro and Kiayias, Aggelos and Knottenbelt, William J.}, booktitle = {Cryptology ePrint Archive}, title = {{SoK: Communication across distributed ledgers}}, year = {2019}, } @article{10878, abstract = {Starting from a microscopic model for a system of neurons evolving in time which individually follow a stochastic integrate-and-fire type model, we study a mean-field limit of the system. Our model is described by a system of SDEs with discontinuous coefficients for the action potential of each neuron and takes into account the (random) spatial configuration of neurons allowing the interaction to depend on it. In the limit as the number of particles tends to infinity, we obtain a nonlinear Fokker-Planck type PDE in two variables, with derivatives only with respect to one variable and discontinuous coefficients. We also study strong well-posedness of the system of SDEs and prove the existence and uniqueness of a weak measure-valued solution to the PDE, obtained as the limit of the laws of the empirical measures for the system of particles.}, author = {Flandoli, Franco and Priola, Enrico and Zanco, Giovanni A}, issn = {1553-5231}, journal = {Discrete and Continuous Dynamical Systems}, keywords = {Applied Mathematics, Discrete Mathematics and Combinatorics, Analysis}, number = {6}, pages = {3037--3067}, publisher = {AIMS}, title = {{A mean-field model with discontinuous coefficients for neurons with spatial interaction}}, doi = {10.3934/dcds.2019126}, volume = {39}, year = {2019}, } @article{6554, abstract = {Due to the importance of zero-shot learning, i.e. classifying images where there is a lack of labeled training data, the number of proposed approaches has recently increased steadily. We argue that it is time to take a step back and to analyze the status quo of the area. The purpose of this paper is three-fold. First, given the fact that there is no agreed upon zero-shot learning benchmark, we first define a new benchmark by unifying both the evaluation protocols and data splits of publicly available datasets used for this task. This is an important contribution as published results are often not comparable and sometimes even flawed due to, e.g. pre-training on zero-shot test classes. Moreover, we propose a new zero-shot learning dataset, the Animals with Attributes 2 (AWA2) dataset which we make publicly available both in terms of image features and the images themselves. Second, we compare and analyze a significant number of the state-of-the-art methods in depth, both in the classic zero-shot setting but also in the more realistic generalized zero-shot setting. Finally, we discuss in detail the limitations of the current status of the area which can be taken as a basis for advancing it.}, author = {Xian, Yongqin and Lampert, Christoph and Schiele, Bernt and Akata, Zeynep}, issn = {1939-3539}, journal = {IEEE Transactions on Pattern Analysis and Machine Intelligence}, number = {9}, pages = {2251 -- 2265}, publisher = {IEEE}, title = {{Zero-shot learning - A comprehensive evaluation of the good, the bad and the ugly}}, doi = {10.1109/tpami.2018.2857768}, volume = {41}, year = {2019}, } @article{7165, abstract = {Cell division, movement and differentiation contribute to pattern formation in developing tissues. This is the case in the vertebrate neural tube, in which neurons differentiate in a characteristic pattern from a highly dynamic proliferating pseudostratified epithelium. To investigate how progenitor proliferation and differentiation affect cell arrangement and growth of the neural tube, we used experimental measurements to develop a mechanical model of the apical surface of the neuroepithelium that incorporates the effect of interkinetic nuclear movement and spatially varying rates of neuronal differentiation. Simulations predict that tissue growth and the shape of lineage-related clones of cells differ with the rate of differentiation. Growth is isotropic in regions of high differentiation, but dorsoventrally biased in regions of low differentiation. This is consistent with experimental observations. The absence of directional signalling in the simulations indicates that global mechanical constraints are sufficient to explain the observed differences in anisotropy. This provides insight into how the tissue growth rate affects cell dynamics and growth anisotropy and opens up possibilities to study the coupling between mechanics, pattern formation and growth in the neural tube.}, author = {Guerrero, Pilar and Perez-Carrasco, Ruben and Zagórski, Marcin P and Page, David and Kicheva, Anna and Briscoe, James and Page, Karen M.}, issn = {1477-9129}, journal = {Development}, number = {23}, publisher = {Company of Biologists}, title = {{Neuronal differentiation influences progenitor arrangement in the vertebrate neuroepithelium}}, doi = {10.1242/dev.176297}, volume = {146}, year = {2019}, } @article{6897, abstract = {The apical hook is a transiently formed structure that plays a protective role when the germinating seedling penetrates through the soil towards the surface. Crucial for proper bending is the local auxin maxima, which defines the concave (inner) side of the hook curvature. As no sign of asymmetric auxin distribution has been reported in embryonic hypocotyls prior to hook formation, the question of how auxin asymmetry is established in the early phases of seedling germination remains largely unanswered. Here, we analyzed the auxin distribution and expression of PIN auxin efflux carriers from early phases of germination, and show that bending of the root in response to gravity is the crucial initial cue that governs the hypocotyl bending required for apical hook formation. Importantly, polar auxin transport machinery is established gradually after germination starts as a result of tight root-hypocotyl interaction and a proper balance between abscisic acid and gibberellins.}, author = {Zhu, Qiang and Gallemi, Marçal and Pospíšil, Jiří and Žádníková, Petra and Strnad, Miroslav and Benková, Eva}, issn = {1477-9129}, journal = {Development}, number = {17}, publisher = {Company of Biologists}, title = {{Root gravity response module guides differential growth determining both root bending and apical hook formation in Arabidopsis}}, doi = {10.1242/dev.175919}, volume = {146}, year = {2019}, } @article{7404, abstract = {The formation of neuronal dendrite branches is fundamental for the wiring and function of the nervous system. Indeed, dendrite branching enhances the coverage of the neuron's receptive field and modulates the initial processing of incoming stimuli. Complex dendrite patterns are achieved in vivo through a dynamic process of de novo branch formation, branch extension and retraction. The first step towards branch formation is the generation of a dynamic filopodium-like branchlet. The mechanisms underlying the initiation of dendrite branchlets are therefore crucial to the shaping of dendrites. Through in vivo time-lapse imaging of the subcellular localization of actin during the process of branching of Drosophila larva sensory neurons, combined with genetic analysis and electron tomography, we have identified the Actin-related protein (Arp) 2/3 complex as the major actin nucleator involved in the initiation of dendrite branchlet formation, under the control of the activator WAVE and of the small GTPase Rac1. Transient recruitment of an Arp2/3 component marks the site of branchlet initiation in vivo. These data position the activation of Arp2/3 as an early hub for the initiation of branchlet formation.}, author = {Stürner, Tomke and Tatarnikova, Anastasia and Müller, Jan and Schaffran, Barbara and Cuntz, Hermann and Zhang, Yun and Nemethova, Maria and Bogdan, Sven and Small, Vic and Tavosanis, Gaia}, issn = {1477-9129}, journal = {Development}, number = {7}, publisher = {Company of Biologists}, title = {{Transient localization of the Arp2/3 complex initiates neuronal dendrite branching in vivo}}, doi = {10.1242/dev.171397}, volume = {146}, year = {2019}, } @inproceedings{9261, abstract = {Bending-active structures are able to efficiently produce complex curved shapes starting from flat panels. The desired deformation of the panels derives from the proper selection of their elastic properties. Optimized panels, called FlexMaps, are designed such that, once they are bent and assembled, the resulting static equilibrium configuration matches a desired input 3D shape. The FlexMaps elastic properties are controlled by locally varying spiraling geometric mesostructures, which are optimized in size and shape to match the global curvature (i.e., bending requests) of the target shape. The design pipeline starts from a quad mesh representing the input 3D shape, which defines the edge size and the total amount of spirals: every quad will embed one spiral. Then, an optimization algorithm tunes the geometry of the spirals by using a simplified pre-computed rod model. This rod model is derived from a non-linear regression algorithm which approximates the non-linear behavior of solid FEM spiral models subject to hundreds of load combinations. This innovative pipeline has been applied to the project of a lightweight plywood pavilion named FlexMaps Pavilion, which is a single-layer piecewise twisted arc that fits a bounding box of 3.90x3.96x3.25 meters.}, author = {Laccone, Francesco and Malomo, Luigi and Perez Rodriguez, Jesus and Pietroni, Nico and Ponchio, Federico and Bickel, Bernd and Cignoni, Paolo}, booktitle = {60th Anniversary Symposium of the International Association for Shell and Spatial Structures}, isbn = {9788412110104}, issn = {2518-6582}, location = {Barcelona, Spain}, pages = {509--515}, publisher = {International Center for Numerical Methods in Engineering}, title = {{FlexMaps Pavilion: A twisted arc made of mesostructured flat flexible panels}}, year = {2019}, } @article{22587, author = {Ivanov, Valeriy and Fatichi, Simone and Daly, Edoardo}, journal = {Oxford Bibliographies in Environmental Science}, publisher = {Oxford University Press}, title = {{Ecohydrology}}, doi = {10.1093/obo/9780199363445-0120}, year = {2019}, } @inproceedings{7606, abstract = {We derive a tight lower bound on equivocation (conditional entropy), or equivalently a tight upper bound on mutual information between a signal variable and channel outputs. The bound is in terms of the joint distribution of the signals and maximum a posteriori decodes (most probable signals given channel output). As part of our derivation, we describe the key properties of the distribution of signals, channel outputs and decodes, that minimizes equivocation and maximizes mutual information. This work addresses a problem in data analysis, where mutual information between signals and decodes is sometimes used to lower bound the mutual information between signals and channel outputs. Our result provides a corresponding upper bound.}, author = {Hledik, Michal and Sokolowski, Thomas R and Tkačik, Gašper}, booktitle = {IEEE Information Theory Workshop, ITW 2019}, isbn = {9781538669006}, location = {Visby, Sweden}, publisher = {IEEE}, title = {{A tight upper bound on mutual information}}, doi = {10.1109/ITW44776.2019.8989292}, year = {2019}, } @inproceedings{11222, author = {Kim, Olena and Borges Merjane, Carolina and Jonas, Peter M}, booktitle = {Intrinsic Activity}, issn = {2309-8503}, keywords = {hippocampus, mossy fibers, readily releasable pool, electron microscopy}, location = {Innsbruck, Austria}, number = {Suppl. 1}, publisher = {Austrian Pharmacological Society}, title = {{Functional analysis of the docked vesicle pool in hippocampal mossy fiber terminals by electron microscopy}}, doi = {10.25006/ia.7.s1-a3.27}, volume = {7}, year = {2019}, } @article{7117, abstract = {We propose a novel generic shape optimization method for CAD models based on the eXtended Finite Element Method (XFEM). Our method works directly on the intersection between the model and a regular simulation grid, without the need to mesh or remesh, thus removing a bottleneck of classical shape optimization strategies. This is made possible by a novel hierarchical integration scheme that accurately integrates finite element quantities with sub-element precision. For optimization, we efficiently compute analytical shape derivatives of the entire framework, from model intersection to integration rule generation and XFEM simulation. Moreover, we describe a differentiable projection of shape parameters onto a constraint manifold spanned by user-specified shape preservation, consistency, and manufacturability constraints. We demonstrate the utility of our approach by optimizing mass distribution, strength-to-weight ratio, and inverse elastic shape design objectives directly on parameterized 3D CAD models.}, author = {Hafner, Christian and Schumacher, Christian and Knoop, Espen and Auzinger, Thomas and Bickel, Bernd and Bächer, Moritz}, issn = {0730-0301}, journal = {ACM Transactions on Graphics}, number = {6}, publisher = {ACM}, title = {{X-CAD: Optimizing CAD Models with Extended Finite Elements}}, doi = {10.1145/3355089.3356576}, volume = {38}, year = {2019}, } @article{7391, abstract = {Electron microscopy (EM) is a technology that enables visualization of single proteins at a nanometer resolution. However, current protein analysis by EM mainly relies on immunolabeling with gold-particle-conjugated antibodies, which is compromised by large size of antibody, precluding precise detection of protein location in biological samples. Here, we develop a specific chemical labeling method for EM detection of proteins at single-molecular level. Rational design of α-helical peptide tag and probe structure provided a complementary reaction pair that enabled specific cysteine conjugation of the tag. The developed chemical labeling with gold-nanoparticle-conjugated probe showed significantly higher labeling efficiency and detectability of high-density clusters of tag-fused G protein-coupled receptors in freeze-fracture replicas compared with immunogold labeling. Furthermore, in ultrathin sections, the spatial resolution of the chemical labeling was significantly higher than that of antibody-mediated labeling. These results demonstrate substantial advantages of the chemical labeling approach for single protein visualization by EM.}, author = {Tabata, Shigekazu and Jevtic, Marijo and Kurashige, Nobutaka and Fuchida, Hirokazu and Kido, Munetsugu and Tani, Kazushi and Zenmyo, Naoki and Uchinomiya, Shohei and Harada, Harumi and Itakura, Makoto and Hamachi, Itaru and Shigemoto, Ryuichi and Ojida, Akio}, issn = {2589-0042}, journal = {iScience}, number = {12}, pages = {256--268}, publisher = {Elsevier}, title = {{Electron microscopic detection of single membrane proteins by a specific chemical labeling}}, doi = {10.1016/j.isci.2019.11.025}, volume = {22}, year = {2019}, } @article{6713, abstract = {Evolutionary studies are often limited by missing data that are critical to understanding the history of selection. Selection experiments, which reproduce rapid evolution under controlled conditions, are excellent tools to study how genomes evolve under selection. Here we present a genomic dissection of the Longshanks selection experiment, in which mice were selectively bred over 20 generations for longer tibiae relative to body mass, resulting in 13% longer tibiae in two replicates. We synthesized evolutionary theory, genome sequences and molecular genetics to understand the selection response and found that it involved both polygenic adaptation and discrete loci of major effect, with the strongest loci tending to be selected in parallel between replicates. We show that selection may favor de-repression of bone growth through inactivating two limb enhancers of an inhibitor, Nkx3-2. Our integrative genomic analyses thus show that it is possible to connect individual base-pair changes to the overall selection response.}, author = {Castro, João Pl and Yancoskie, Michelle N. and Marchini, Marta and Belohlavy, Stefanie and Hiramatsu, Layla and Kučka, Marek and Beluch, William H. and Naumann, Ronald and Skuplik, Isabella and Cobb, John and Barton, Nicholas H and Rolian, Campbell and Chan, Yingguang Frank}, journal = {eLife}, publisher = {eLife Sciences Publications}, title = {{An integrative genomic analysis of the Longshanks selection experiment for longer limbs in mice}}, doi = {10.7554/eLife.42014}, volume = {8}, year = {2019}, } @phdthesis{6435, abstract = {Social insect colonies tend to have numerous members which function together like a single organism in such harmony that the term ``super-organism'' is often used. In this analogy the reproductive caste is analogous to the primordial germ cells of a metazoan, while the sterile worker caste corresponds to somatic cells. The worker castes, like tissues, are in charge of all functions of a living being, besides reproduction. The establishment of new super-organismal units (i.e. new colonies) is accomplished by the co-dependent castes. The term oftentimes goes beyond a metaphor. We invoke it when we speak about the metabolic rate, thermoregulation, nutrient regulation and gas exchange of a social insect colony. Furthermore, we assert that the super-organism has an immune system, and benefits from ``social immunity''. Social immunity was first summoned by evolutionary biologists to resolve the apparent discrepancy between the expected high frequency of disease outbreak amongst numerous, closely related tightly-interacting hosts, living in stable and microbially-rich environments, against the exceptionally scarce epidemic accounts in natural populations. Social immunity comprises a multi-layer assembly of behaviours which have evolved to effectively keep the pathogenic enemies of a colony at bay. The field of social immunity has drawn interest, as it becomes increasingly urgent to stop the collapse of pollinator species and curb the growth of invasive pests. In the past decade, several mechanisms of social immune responses have been dissected, but many more questions remain open. I present my work in two experimental chapters. In the first, I use invasive garden ants (*Lasius neglectus*) to study how pathogen load and its distribution among nestmates affect the grooming response of the group. Any given group of ants will carry out the same total grooming work, but will direct their grooming effort towards individuals carrying a relatively higher spore load. Contrary to expectation, the highest risk of transmission does not stem from grooming highly contaminated ants, but instead, we suggest that the grooming response likely minimizes spore loss to the environment, reducing contamination from inadvertent pickup from the substrate. The second is a comparative developmental approach. I follow black garden ant queens (*Lasius niger*) and their colonies from mating flight, through hibernation for a year. Colonies which grow fast from the start, have a lower chance of survival through hibernation, and those which survive grow at a lower pace later. This is true for colonies of naive and challenged queens. Early pathogen exposure of the queens changes colony dynamics in an unexpected way: colonies from exposed queens are more likely to grow slowly and recover in numbers only after they survive hibernation. In addition to the two experimental chapters, this thesis includes a co-authored published review on organisational immunity, where we enlist the experimental evidence and theoretical framework on which this hypothesis is built, identify the caveats and underline how the field is ripe to overcome them. In a final chapter, I describe my part in two collaborative efforts, one to develop an image-based tracker, and the second to develop a classifier for ant behaviour.}, author = {Casillas Perez, Barbara E}, issn = {2663-337X}, keywords = {Social Immunity, Sanitary care, Social Insects, Organisational Immunity, Colony development, Multi-target tracking}, pages = {183}, publisher = {Institute of Science and Technology Austria}, title = {{Collective defenses of garden ants against a fungal pathogen}}, doi = {10.15479/AT:ISTA:6435}, year = {2019}, } @article{6830, author = {Contreras, Ximena and Hippenmeyer, Simon}, issn = {1097-4199}, journal = {Neuron}, number = {5}, pages = {750--752}, publisher = {Elsevier}, title = {{Memo1 tiles the radial glial cell grid}}, doi = {10.1016/j.neuron.2019.08.021}, volume = {103}, year = {2019}, }