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1. On Sparse Hitting Sets: from Fair Vertex Cover to Highway Dimension

Author

Blum, Johannes, Disser, Yann, Feldmann, Andreas Emil, Gupta, Siddharth, and Zych-Pawlewicz, Anna

Subjects
Computer Science - Data Structures and Algorithms, Computer Science - Computational Complexity, Computer Science - Discrete Mathematics
Abstract

We consider the Sparse Hitting Set (Sparse-HS) problem, where we are given a set system $(V,\mathcal{F},\mathcal{B})$ with two families $\mathcal{F},\mathcal{B}$ of subsets of $V$. The task is to find a hitting set for $\mathcal{F}$ that minimizes the maximum number of elements in any of the sets of $\mathcal{B}$. Our focus is on determining the complexity of some special cases of Sparse-HS with respect to the sparseness $k$, which is the optimum number of hitting set elements in any set of $\mathcal{B}$. For the Sparse Vertex Cover (Sparse-VC) problem, $V$ is given by the vertex set of a graph, and $\mathcal{F}$ is its edge set. We prove NP-hardness for sparseness $k\geq 2$ and polynomial time solvability for $k=1$. We also provide a polynomial-time $2$-approximation for any $k$. A special case of Sparse-VC is Fair Vertex Cover (Fair-VC), where the family $\mathcal{B}$ is given by vertex neighbourhoods. For this problem we prove NP-hardness for constant $k$ and provide a polynomial-time $(2-\frac{1}{k})$-approximation. This is better than any approximation possible for Sparse-VC or Vertex Cover (under UGC). We then consider two problems derived from Sparse-HS related to the highway dimension, a graph parameter modelling transportation networks. Most algorithms for graphs of low highway dimension compute solutions to the $r$-Shortest Path Cover ($r$-SPC) problem, where $r>0$, $\mathcal{F}$ contains all shortest paths of length between $r$ and $2r$, and $\mathcal{B}$ contains all balls of radius $2r$. There is an XP algorithm that computes solutions to $r$-SPC of sparseness at most $h$ if the input graph has highway dimension $h$, but the existence if an FPT algorithm was open. We prove that $r$-SPC and also the related $r$-Highway Dimension ($r$-HD) problem are both W[1]-hard. Furthermore, we prove that $r$-SPC admits a polynomial-time $O(\log n)$-approximation.

Published
2022

2. Customizable Hub Labeling: Properties and Algorithms

Author

Blum, Johannes and Storandt, Sabine

Subjects
Computer Science - Data Structures and Algorithms
Abstract

Hub Labeling (HL) is one of the state-of-the-art preprocessing-based techniques for route planning in road networks. It is a special incarnation of distance labeling, and it is well-studied in both theory and practice. The core concept of HL is to associate a label with each vertex, which consists of a subset of all vertices and respective shortest path information, such that the shortest path distance between any two vertices can be derived from considering the intersection of their labels. HL provides excellent query times but requires a time-consuming preprocessing phase. Therefore, in case of edge cost changes, rerunning the whole preprocessing is not viable. Inspired by the concept of Customizable Route Planning, we hence propose in this paper a Customizable Hub Labeling variant for which the edge costs in the network do not need to be known at construction time. These labels can then be used with any edge costs after conducting a so called customization phase. We study the theoretical properties of Customizable Hub Labelings, provide an $\mathcal{O}(\log^2 n)$-approximation algorithm for the average label size, and propose efficient customization algorithms.

Published
2022

3. W[1]-Hardness of the k-Center Problem Parameterized by the Skeleton Dimension

Author

Blum, Johannes

Subjects
Computer Science - Computational Complexity
Abstract

In the $k$-Center problem, we are given a graph $G=(V,E)$ with positive edge weights and an integer $k$ and the goal is to select $k$ center vertices $C \subseteq V$ such that the maximum distance from any vertex to the closest center vertex is minimized. On general graphs, the problem is NP-hard and cannot be approximated within a factor less than $2$. Typical applications of the $k$-Center problem can be found in logistics or urban planning and hence, it is natural to study the problem on transportation networks. Such networks are often characterized as graphs that are (almost) planar or have low doubling dimension, highway dimension or skeleton dimension. It was shown by Feldmann and Marx that $k$-Center is W[1]-hard on planar graphs of constant doubling dimension when parameterized by the number of centers $k$, the highway dimension $hd$ and the pathwidth $pw$. We extend their result and show that even if we additionally parameterize by the skeleton dimension $\kappa$, the $k$-Center problem remains W[1]-hard. Moreover, we prove that under the Exponential Time Hypothesis there is no exact algorithm for $k$-Center that has runtime $f(k,hd,pw,\kappa) \cdot \vert V \vert^{o(pw + \kappa + \sqrt{k+hd})}$ for any computable function $f$.

Published
2020

5. Hierarchy of Transportation Network Parameters and Hardness Results

Author

Blum, Johannes

Subjects
Computer Science - Discrete Mathematics, Computer Science - Computational Complexity
Abstract

The graph parameters highway dimension and skeleton dimension were introduced to capture the properties of transportation networks. As many important optimization problems like Travelling Salesperson, Steiner Tree or $k$-Center arise in such networks, it is worthwhile to study them on graphs of bounded highway or skeleton dimension. We investigate the relationships between mentioned parameters and how they are related to other important graph parameters that have been applied successfully to various optimization problems. We show that the skeleton dimension is incomparable to any of the parameters distance to linear forest, bandwidth, treewidth and highway dimension and hence, it is worthwhile to study mentioned problems also on graphs of bounded skeleton dimension. Moreover, we prove that the skeleton dimension is upper bounded by the max leaf number and that for any graph on at least three vertices there are edge weights such that both parameters are equal. Then we show that computing the highway dimension according to most recent definition is NP-hard, which answers an open question stated by Feldmann et al. Finally we prove that on graphs $G=(V,E)$ of skeleton dimension $\mathcal{O}(\log^2 \vert V \vert)$ it is NP-hard to approximate the $k$-Center problem within a factor less than $2$.

Published
2019

6. Planar Steiner Orientation is NP-complete

Author

Beck, Moritz, Blum, Johannes, Kryven, Myroslav, Löffler, Andre, and Zink, Johannes

Subjects
Computer Science - Discrete Mathematics, Computer Science - Computational Complexity, Computer Science - Data Structures and Algorithms
Abstract

Many applications in graph theory are motivated by routing or flow problems. Among these problems is Steiner Orientation: given a mixed graph G (having directed and undirected edges) and a set T of k terminal pairs in G, is there an orientation of the undirected edges in G such that there is a directed path for every terminal pair in T ? This problem was shown to be NP -complete by Arkin and Hassin [1] and later W [1]-hard by Pilipczuk and Wahlstr\"om [7], parametrized by k. On the other hand, there is an XP algorithm by Cygan et al. [3] and a polynomial time algorithm for graphs without directed edges by Hassin and Megiddo [5]. Chitnis and Feldmann [2] showed W [1]-hardness of the problem for graphs of genus 1. We consider a further restriction to planar graphs and show NP -completeness.

Published
2018

7. Treatment outcome of imported cutaneous leishmaniasis among travelers and migrants infected with Leishmania major and Leishmania tropica: a retrospective study in European centers 2013 to 2019

Author

Glans, Hedvig, Dotevall, Leif, Van der Auwera, Gert, Bart, Aldert, Blum, Johannes, Buffet, Pierre, Guery, Romain, Gangneux, Jean-Pierre, van Henten, Saskia, Harms, Gundel, Varani, Stefania, Robert-Gangneux, Florence, Rongisch, Robert, Andersson, Björn, and Bradley, Maria

Published
2022
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12. List of Contributors

Author

Adamczick, Charlotte, primary, Aldrich, Cassandra, additional, Ariyoshi, Koya, additional, Babji, Sudhir, additional, Bastawrous, Andrew, additional, Bates, M. Jane, additional, Bausch, Daniel G., additional, Beare, Nicholas A.V., additional, Berto, Cesar G., additional, Blum, Johannes, additional, Boelaert, Marleen, additional, Burchard, Gerd-Dieter, additional, Bustamante, Beatriz, additional, Velasco, Fátima Concha, additional, Cordero, Fernando Mejía, additional, M. Coyle, Christina, additional, Currie, Bart J., additional, Dance, David A.B., additional, Day, Jeremy, additional, Dieckmann, Sebastian, additional, Ekem, Ivy, additional, El-Dib, Nadia, additional, Douangnoulak, Viravong, additional, Fernández, Facundo M., additional, Friedlander, Arthur M., additional, Goens, Cristina, additional, Gotuzzo, Eduardo H., additional, Green, Michael D., additional, D. Harries, Anthony, additional, Howlett, William P., additional, Ignatius, Ralf, additional, Inthalad, Saythong, additional, Ishida, Kentaro, additional, Jacquerioz, Frederique, additional, Jeffs, Benjamin, additional, Jochum, Johannes, additional, Jones, Nick, additional, Jordan, Sabine, additional, Kang, Gagandeep, additional, Katchanov, Juri, additional, Keoluangkhot, Valy, additional, Kluxen, Guido, additional, Kong, Yoon, additional, Kuenzli, Esther, additional, Lambert, Saba M., additional, Latthaphasavang, Vatthanaphone, additional, Llanos-Cuentas, Alejandro, additional, Legua, Pedro, additional, Libman, Michael, additional, Molyneux, Elizabeth M., additional, Mabey, David C.W., additional, Mackroth, Maria S., additional, Maguiña, Ciro, additional, Mani, Reeta S., additional, Marks, Michael, additional, Martínez, Dalila, additional, Maruyama, Haruhiko, additional, Mathuram, Alice, additional, Matsui, Kohsuke, additional, Mayxay, Mayfong, additional, McCarthy, James, additional, Mitià, Oriol, additional, Miller, Robert F., additional, Molina, Israel, additional, Morguet, Andreas J., additional, Nakase, Hiroyuki, additional, Nawa, Yukifumi, additional, Neumayr, Andreas, additional, Newton, Paul N., additional, Nguyen, Thi Thuy Ngan, additional, Fhogartaigh, Caoimhe Nic, additional, Nishimura, Fumihiko, additional, Norindr, Buachan, additional, Ouji, Yukiteru, additional, Pollach, Gregor, additional, Postels, Douglas G., additional, Premaratna, Ranjan, additional, Rattanavong, Sayaphet, additional, Ritmeijer, Koert, additional, Rono, Hillary K., additional, Roodnat, Karen, additional, Rothe, Camilla, additional, Rupali, Priscilla, additional, Sa-ngaimwibool, Prakasit, additional, Schneider, Thomas, additional, Schwering, Markus Schulze, additional, Seas, Carlos, additional, Sey, Fredericka, additional, Siddiqi, Omar, additional, Siebert, Eberhard, additional, Sisouphonh, Siho, additional, Slesak, Günther, additional, Smith, Chris, additional, Sothmann, Peter, additional, Soukaloun, Douangdao, additional, Srour, M. Leila, additional, Staehelin, Cornelia, additional, Stocker, Hartmut, additional, Stojkovic, Marija, additional, Takahashi, Kensuke, additional, Takamatsu, Hiroko, additional, Tannich, E., additional, Tomita, Masaki, additional, van Oosterhout, Joep J., additional, Verdonck, Kristien, additional, Vogel, Moritz, additional, Walker, Stephen L., additional, Wall, Emma C., additional, Weitzel, Thomas, additional, Whitty, Christopher J.M., additional, Woldeamanuel, Yohannes W., additional, Wright, Mary E., additional, Yacoub, Sophie, additional, and Yoshikawa, Masahide, additional

Published
2022
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15. FISSION: A Practical Algorithm for Computing Minimum Balanced Node Separators

Author

Blum, Johannes, Li, Ruoying, Storandt, Sabine, Goos, Gerhard, Founding Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Woeginger, Gerhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Wu, Weili, editor, and Zhang, Zhongnan, editor

Published
2020
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22. Computation and Growth of Road Network Dimensions

Author

Blum, Johannes, Storandt, Sabine, Hutchison, David, Series Editor, Kanade, Takeo, Series Editor, Kittler, Josef, Series Editor, Kleinberg, Jon M., Series Editor, Mattern, Friedemann, Series Editor, Mitchell, John C., Series Editor, Naor, Moni, Series Editor, Pandu Rangan, C., Series Editor, Steffen, Bernhard, Series Editor, Terzopoulos, Demetri, Series Editor, Tygar, Doug, Series Editor, Weikum, Gerhard, Series Editor, Wang, Lusheng, editor, and Zhu, Daming, editor

Published
2018
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29. Properties of Regular DAG Languages

Author

Blum, Johannes, Drewes, Frank, Hutchison, David, Series editor, Kanade, Takeo, Series editor, Kittler, Josef, Series editor, Kleinberg, Jon M., Series editor, Mattern, Friedemann, Series editor, Mitchell, John C., Series editor, Naor, Moni, Series editor, Pandu Rangan, C., Series editor, Steffen, Bernhard, Series editor, Terzopoulos, Demetri, Series editor, Tygar, Doug, Series editor, Weikum, Gerhard, Series editor, Dediu, Adrian-Horia, editor, Janoušek, Jan, editor, Martín-Vide, Carlos, editor, and Truthe, Bianca, editor

Published
2016
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30. Specificity, cross-reactivity, and function of antibodies elicited by Zika virus infection

Author

Stettler, Karin, Beltramello, Martina, Espinosa, Diego A., Graham, Victoria, Cassotta, Antonino, Bianchi, Siro, Vanzetta, Fabrizia, Minola, Andrea, Jaconi, Stefano, Mele, Federico, Foglierini, Mathilde, Pedotti, Mattia, Simonelli, Luca, Dowall, Stuart, Atkinson, Barry, Percivalle, Elena, Simmons, Cameron P., Varani, Luca, Blum, Johannes, Baldanti, Fausto, Cameroni, Elisabetta, Hewson, Roger, Harris, Eva, Lanzavecchia, Antonio, Sallusto, Federica, and Corti, Davide

Published
2016

31. Cardiac involvement in Chagas disease and African trypanosomiasis

Author

Sabino, Ester Cerdeira, Nunes, Maria Carmo P., Blum, Johannes, Molina, Israel, and Ribeiro, Antonio Luiz P.

Abstract

Trypanosomiases are diseases caused by various species of protozoan parasite in the genus Trypanosoma, each presenting with distinct clinical manifestations and prognoses. Infections can affect multiple organs, with Trypanosomacruzipredominantly affecting the heart and digestive system, leading to American trypanosomiasis or Chagas disease, and Trypanosomabruceiprimarily causing a disease of the central nervous system known as human African trypanosomiasis or sleeping sickness. In this Review, we discuss the effects of these infections on the heart, with particular emphasis on Chagas disease, which continues to be a leading cause of cardiomyopathy in Latin America. The epidemiology of Chagas disease has changed substantially since 1990 owing to the emigration of over 30 million Latin American citizens, primarily to Europe and the USA. This movement of people has led to the global dissemination of individuals infected with T. cruzi. Therefore, cardiologists worldwide must familiarize themselves with Chagas disease and the severe, chronic manifestation — Chagas cardiomyopathy — because of the expanded prevalence of this disease beyond traditional endemic regions.

Published
2024
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32. Kurz kommentiert

Author

Jehmlich, Tommy, Thießen, Friedrich, Haucap, Justus, Sieg, Gernot, Blum, Johannes, and Potrafke, Niklas

Published
2019
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35. A Parameterized View on Transportation Networks : Algorithms, Hierarchy, and Complexity

Author

Blum, Johannes

Subjects
graph parameter, transportation network, skeleton dimension, highway dimension, bounded growth, hub labeling, contraction hierarchy, route planning, k-center, ddc:004
Abstract

Many everyday optimization problems arise in transportation networks, such as vehicle and pedestrian navigation, truck route planning, or facility location problems in logistics. To solve such problems, efficient algorithms are required. To that end, the transportation network is usually modeled as a graph, where the vertices represent locations (e.g., road intersections or train stations) and the edges represent connections between them. To develop efficient algorithms for the corresponding graph problems, it is in many cases beneficial to exploit certain properties of the resulting graph. This motivated the development of several models for graphs representing transportation networks, e.g., the graph parameters highway dimension and skeleton dimension, which capture the structure of shortest paths in a graph, or bounded growth graphs. In this work, we consider different parameters that are commonly used to model transportation networks. We utilize them to develop efficient algorithms, study the relationships between different parameters, and demonstrate the limitations of these models. In the first part, we consider the shortest path problem. Three of the most successful algorithms for this problem in transportation networks are Contraction Hierarchies, Hub Labeling, and Transit Node Routing. First, we investigate these algorithms on bounded growth graphs. A graph has bounded growth if there is a constant g such that for any vertex u and any r>0, the number of vertices at distance r from u is at most g⋅r. We improve upon a previous result of Funke and Storandt [ISAAC '15] and show that in this model, it is possible to achieve a space consumption of O(n log D) for Contraction Hierarchies on unweighted graphs, where D denotes the diameter of the graph. Furthermore, we analyze the search space sizes and space consumption of Hub Labeling and Transit Node Routing on bounded growth graphs, and also consider weighted graphs. We then study variants of Hub Labeling and Contraction Hierarchies, and show that we can lower bound the size of their respective search spaces in terms of the size of minimum balanced separators. This allows us to develop a O(log2 n)-approximation algorithm for the search spaces sizes. In the second part, we consider various graph parameters, including highway dimension, skeleton dimension, and bounded growth number. We study the relationships between different parameters, which allows us to incorporate them into a hierarchy. The third part is concerned with the computational complexity of two graph problems. We show that it is NP-hard to compute the highway dimension of a graph according to the recent definition of Abraham et al. [J. ACM '16]. Moreover, we develop a polynomial time algorithm to compute the highway dimension of a tree.Finally, we consider the k-Center problem. First, we show that for any ϵ>0 it is NP-hard to compute a (2-ϵ)-approximation if the given graph has a skeleton dimension of κ ∈ O(log2 n). Finally, we study the fixed-parameter tractability of k-Center and show that the problem is W[1]-hard if the parameter combines the number of centers, the highway dimension, the skeleton dimension and the pathwidth, even if the given graph is planar and has constant doubling dimension. published

Published
2023

39. Panzytopenie und akutes Nierenversagen

Author

Greiner, Michael, primary, Treichler, Gina, additional, Morel, Corinne, additional, Camenzind, Dominik, additional, Neumayer, Andreas, additional, Blum, Johannes, additional, and Beer, Jrg Hans, additional

Published
2022
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40. Pancytopénie et insuffisance rénale aiguë

Author

Greiner, Michael, primary, Treichler, Gina, additional, Morel, Corinne, additional, Camenzind, Dominik, additional, Neumayer, Andreas, additional, Blum, Johannes, additional, and Beer, Jrg Hans, additional

Published
2022
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42. List of Contributors

Author

Abrahamian, Fredrick M., primary, Aldape, Michael J., additional, Aldasoro, Edelweiss, additional, Allen, Upton D., additional, Al-Sum, Hythem, additional, Anadkat, Milan J., additional, Anders, Katherine, additional, Angelakis, Emmanouil, additional, Angus, Brian John, additional, Antoniadou, Anastasia, additional, Arena, Fabio, additional, Arends, Joop E., additional, Arribas, Jose R., additional, Artenstein, Andrew W., additional, Atherton, John C., additional, Aucott, John N., additional, Aw, Tar-Ching, additional, Babcock, Hilary M., additional, Bailey, Robin, additional, Bailey, Thomas C., additional, Banks, Adam Z., additional, Barillo, David J., additional, Barrette, Ernie-Paul, additional, Bauer, Martijn P., additional, Bayston, Roger, additional, Beard, C. Ben, additional, Beardsley, Justin, additional, Beeching, Nick J., additional, Bégué, Rodolfo E., additional, Beldi, Guido, additional, Benson, Constance A., additional, Berbari, Elie F., additional, Berenger, Jean-Michel, additional, Berger, Christoph, additional, Bernardino, Jose I., additional, Bille, Jacques, additional, Billioux, Alexander C., additional, Bitnun, Ari, additional, Blair, Iain, additional, Blanche, Stéphane, additional, Bleck, Thomas P., additional, Bleeker-Rovers, Chantal P., additional, Bleijenberg, Gijs, additional, Bloch, Karen C., additional, Blum, Johannes, additional, Blumberg, Emily A., additional, Bonomo, Robert A., additional, Bonten, Marc J.M., additional, Bourayou, Rafik, additional, Bouza, Emilio, additional, Brandt, K. Ashley, additional, Bretelle, Florence, additional, Brisse, Sylvain, additional, Britton, Warwick J., additional, Brook, Itzhak, additional, Brouwer, Matthijs C., additional, Browne, Sarah K., additional, Bryant, Amy E., additional, Bühler, Silja, additional, Bulger, Eileen M., additional, Buller, R. Mark L., additional, Burke, Leah A., additional, Burri, Christian, additional, Butler, Marcus W., additional, Calandra, Thierry, additional, Calfee, David P., additional, Calvo-Cano, Antonia, additional, Cameron, D. William, additional, Carcillo, Joseph A., additional, Carson, Gail, additional, Chambers, Stephen T., additional, Charrel, Remi N., additional, Nguyen, Vinh Chau Van, additional, Chevaliez, Stéphane, additional, Chiller, Tom M., additional, Christaki, Eirini, additional, Chung, Kevin K., additional, Clifford, David B., additional, Clumeck, Nathan, additional, Cohen, Jonathan, additional, Collinge, John, additional, Conlon, Christopher P., additional, Conrad, Curdin, additional, Cooke, Fiona J., additional, Cope, Jennifer Rittenhouse, additional, Corey, G. Ralph, additional, Cross, John H., additional, Cunha, Burke A., additional, Cunha, Cheston B., additional, D'Journo, Benoit, additional, Daikos, George L., additional, Daniels, Johannes M.A., additional, Davidson, Robert N., additional, Day, Nicholas P.J., additional, De Cock, Kevin M., additional, de Silva, Thushan I., additional, de Vries, Henry J.C., additional, de Wit, Stéphane, additional, Delaloye, Julie, additional, Denning, David W., additional, Dennis, David T., additional, Dhanireddy, Shireesha, additional, Dielubanza, Elodi J., additional, Diemert, David J., additional, Doganay, Mehmet, additional, Doherty, Tom, additional, Dolecek, Christiane, additional, Dondorp, Arjen M., additional, Douglas, Abby, additional, Drancourt, Michel, additional, Dubourg, Grégory, additional, Dudley, Michael N., additional, Durand, Guillaume, additional, Eckhardt, Benjamin J., additional, Efstratiou, Androulla, additional, Ekkelenkamp, Miquel B., additional, Eranki, Ambika, additional, Erdem, Hakan, additional, Escota, Gerome V., additional, Evans, Heather L., additional, Eziefula, Alice Chijioke, additional, Fenollar, Florence, additional, Fenwick, Alan, additional, Fierer, Joshua, additional, Finch, Roger G., additional, Fleckenstein, James M., additional, Forstner, Christina, additional, Foschi, Federico, additional, Fournier, Pierre-Edouard, additional, French, Martyn A., additional, Gage, Kenneth L., additional, Garcia, Lynne S., additional, Gascon, Joaquim, additional, Gastañaduy, Arturo S., additional, Gautret, Philippe, additional, Geisler, William M., additional, Ghanem, Khalil G., additional, Giani, Tommaso, additional, Giannella, Maddalena, additional, Gilliam, Bruce L., additional, Gilliet, Michel, additional, Glaser, Carol A., additional, Glupczynski, Youri, additional, Gnann, John W., additional, Goldstein, Ellie J.C., additional, Gottstein, Bruno, additional, Gouriet, Frederique, additional, Gravitt, Patti E., additional, Green, Michael D., additional, Green, Stephen T., additional, Groll, Andreas H., additional, Gulick, Roy M., additional, Gupta, Arjun, additional, Habib, Gilbert, additional, Harbarth, Stephan, additional, Harris, Marianne, additional, Hayden, Frederick G., additional, Hetem, David J., additional, Hill, Philip C., additional, Hirschel, Bernard, additional, Hodowanec, Aimee C., additional, Hoffart, Louis, additional, Hoffmann, Christian, additional, Holland, Steven M., additional, Horby, Peter W., additional, Horne, David J., additional, Hraiech, Sami, additional, Hull, Mark W., additional, Huttner, Angela, additional, Ingram, Richard J.M., additional, Islam, Jasmin, additional, Ison, Michael G., additional, James, Scott H., additional, Jenkins, Claire, additional, Jenkins, Stephen G., additional, Jensen, Jørgen Skov, additional, Johnston, Christine, additional, Jones, Theodore B., additional, Jordan, Stephen J., additional, Julian, Kathleen G., additional, Kato, Yasuyuki, additional, Kauffman, Carol A., additional, Kaye, Keith S., additional, Keane, Michael P., additional, Keeney, James, additional, Kelly, Paul, additional, Kent, Stephen J., additional, Kern, Winfried V., additional, Keynan, Yoav, additional, Kim, Andrea A., additional, Koné-Paut, Isabelle, additional, Kosmidis, Chris, additional, Kroes, Aloys C.M., additional, Kroon, Frank P., additional, Ksiazek, Thomas G., additional, Kuhlmann, F. Matthew, additional, Kuijper, Ed J., additional, Kwon, Jennie H., additional, Kyei, George B., additional, Lacombe, Karine, additional, Lagacé-Wiens, Philippe, additional, Lagier, Jean-Christophe, additional, Lamagni, Theresa, additional, Landraud, Luce, additional, Lanternier, Fanny, additional, LaPlante, Kerry L., additional, Lawn, Stephen D., additional, Lawrence, Steven J., additional, Leblebicioglu, Hakan, additional, Lee, Nelson, additional, Leggett, James E., additional, Lehours, Philippe, additional, Levy, Pierre-Yves, additional, Leyh, Rainer G., additional, Lillis, Rebecca A., additional, Limmathurotsakul, Direk, additional, Lin, Jennifer, additional, Lindquist, H.D. Alan, additional, Lipsky, Benjamin A., additional, Liscynesky, Christina, additional, Looney, David, additional, Lortholary, Olivier, additional, Lowy, Franklin D., additional, Luft, Benjamin J., additional, Mackowiak, Philip A., additional, MacPherson, Paul A., additional, Maghraoui-Slim, Valérie, additional, Mallon, Patrick W., additional, Mangino, Julie E., additional, Manuel, Oriol, additional, Marchetti, Oscar, additional, Marks, Kristen M., additional, Marr, Kieren A., additional, Marrazzo, Jeanne, additional, Marschall, Jonas, additional, Martin, David H., additional, Matonti, Frédéric, additional, Matulewicz, Richard S., additional, Mayer, Kenneth H., additional, McCulloh, Russell J., additional, McGready, Rose, additional, Mdodo, Rennatus, additional, Mead, Simon, additional, Mégraud, Francis, additional, Meintjes, Graeme, additional, Metcalf, Sarah C., additional, Michaels, Marian G., additional, Migliori, Giovanni Battista, additional, Miles, Michael A., additional, Miller, Alastair, additional, Mimiaga, Matthew J., additional, Mingeot-Leclercq, Marie-Paule, additional, Misch, Elizabeth Ann, additional, Mitreva, Makedonka, additional, Montaner, Julio S.G., additional, Moore, Caroline B., additional, Muñoz, Patricia, additional, Muñoz, Jose, additional, Murray, Clinton K., additional, Musso, Didier, additional, Mutengo, Mable, additional, Mutizwa, Misha M., additional, Naber, Kurt G., additional, Natarajan, Pavithra, additional, Neme, Santiago, additional, Newton, Paul N., additional, Nichols, Ronald A., additional, Nicolle, Lindsay E., additional, Nosten, François, additional, Notarangelo, Luigi D., additional, Nutman, Thomas B., additional, Nyirjesy, Paul, additional, O'Connell, P. Ronan, additional, Opal, Steven M., additional, Ormerod, L. Peter, additional, Osmon, Douglas R., additional, Pankert, Marie Boulze, additional, Pantaleo, Giuseppe, additional, Papazian, Laurent, additional, Parente, Diane M., additional, Parola, Philippe, additional, Parsaei, Shadi, additional, Pascual, Manuel A., additional, Patel, Rupa, additional, Patrozou, Eleni, additional, Pawlotsky, Jean-Michel, additional, Peacock, Sharon J., additional, Pechère, Jean-Claude, additional, Pelegrin, Ivan, additional, Peters, Barry S., additional, Peters, Edgar J.G., additional, Petersen, Jeannine M., additional, Petersen, Lyle R., additional, Petraitis, Vidmantas, additional, Pham, Luu-Ly, additional, Picado, Albert, additional, Pilatz, Adrian, additional, Pilmis, Benoit, additional, Pinazo, María-Jesús, additional, Pletz, Mathias W., additional, Pogue, Jason M., additional, Polgreen, Evelyn L., additional, Polgreen, Philip M., additional, Posfay-Barbe, Klara M., additional, Powderly, William G., additional, Presti, Rachel, additional, Prod'hom, Guy, additional, Puolakkainen, Mirja, additional, Quinn, Thomas C., additional, Raoult, Didier, additional, Razonable, Raymund R., additional, Read, Robert C., additional, Redfield, Robert R., additional, Rentenaar, Rob J., additional, Reynolds, Steven J., additional, Ribi, Camillo, additional, Richardson, Malcolm D., additional, Ritter, Michele L., additional, Roch, Antoine, additional, Rockstroh, Jürgen Kurt, additional, Rojek, Amanda, additional, Romero, José R., additional, Rooijakkers, Suzan H.M., additional, Rosenbluth, Daniel, additional, Rosenzweig, Sergio D., additional, Rossolini, Gian Maria, additional, Rubinstein, Ethan, additional, Ryan, Greg, additional, Safren, Steven A., additional, Sahasrabuddhe, Vikrant V., additional, Saikku, Pekka A.I., additional, Sajadi, Mohammad M., additional, Salvaggio, Michelle R., additional, Santos, Carlos A.Q., additional, Satlin, Michael J., additional, Schaeffer, Anthony J., additional, Schimmer, Christoph, additional, Schooley, Robert T., additional, Schumacher, Richard F., additional, Sha, Beverly E., additional, Shapiro, Daniel S., additional, Sheehan, Gerard, additional, Shlaes, David M., additional, Shoham, Shmuel, additional, Simmons, Cameron P., additional, Simon, Dennis W., additional, Simon, Matthew S., additional, Simonsen, Kari A., additional, Slack, Mary P.E., additional, Smith, Tyrel T., additional, Sobel, Jack D., additional, Souli, Maria, additional, Sridhar, Shruti, additional, Steckelberg, James M., additional, Stevens, Dennis L., additional, Strah, Heather, additional, Sturm, A. Willem, additional, Sungkanuparph, Somnuek, additional, Tabrizi, Sarah J., additional, Tacconelli, Evelina, additional, Tan, Chen Sabrina, additional, Taplitz, Randy A., additional, Thomas, Guillemette, additional, Thomas, Lora D., additional, Thuny, Franck, additional, Thwaites, Guy, additional, Tissot, Frederic, additional, Tønjum, Tone, additional, Torriani, Francesca J., additional, Toso, Christian, additional, Tulkens, Paul M., additional, Tunkel, Allan R., additional, Turner, Claire E., additional, Ustianowski, Andrew P., additional, van Bambeke, Françoise, additional, van Crevel, Reinout, additional, van de Beek, Diederik, additional, van Delden, Christian, additional, van der Eerden, Menno M., additional, van der Meer, Jos W.M., additional, van der Poll, Tom, additional, van Ingen, Jakko, additional, van Putten, Jos, additional, Vaudaux, Bernard P., additional, Vermund, Sten H., additional, Viscidi, Raphael P., additional, Visvanathan, Kumar, additional, Visvesvara, Govinda S., additional, von Seidlein, Lorenz, additional, Wagenlehner, Florian M.E., additional, Wald, Anna, additional, Walsh, Thomas J., additional, Warhurst, David C., additional, Warnock, David W., additional, Warrell, David A., additional, Warrell, Mary J., additional, Warris, Adilia, additional, Watkins, Richard R., additional, Weatherall, David J., additional, Weber, Rainer, additional, Weidner, Wolfgang, additional, White, Jonathan R., additional, White, Peter J., additional, Whitehorn, James, additional, Whitley, Richard J., additional, Whitty, Christopher J.M., additional, Wiersinga, Willem Joost, additional, Wilcox, Mark H., additional, Williams, Thomas N., additional, Wilson, Cara C., additional, Wilson, Mary Elizabeth, additional, Wisplinghoff, Hilmar, additional, Wood, Robin, additional, Wunderink, Richard G., additional, Wyles, David, additional, Yang, Zhi-Tao, additional, Yoder, Jonathan S., additional, Zaidi, Najam A., additional, Zimmer, Andrea J., additional, Zuckerman, Jane N., additional, and Zumla, Alimuddin, additional

Published
2017
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44. Surveillance of leishmaniasis cases from 15 European centres, 2014 to 2019: a retrospective analysis

Author

Van der Auwera, Gert, Davidsson, Leigh, Buffet, Pierre, Ruf, Marie-Thérèse, Gramiccia, Marina, Varani, Stefania, Chicharro, Carmen, Bart, Aldert, Harms, Gundel, Chiodini, Peter L, Brekke, Hanne, Robert-Gangneux, Florence, Cortes, Sofia, Verweij, Jaco J, Scarabello, Alessandra, Karlsson Söbirk, Sara, Guéry, Romain, van Henten, Saskia, Di Muccio, Trentina, Carra, Elena, van Thiel, Pieter, Vandeputte, Martin, Gaspari, Valeria, Blum, Johannes, LeishMan Surveillance network, Van der Auwera G., Davidsson L., Buffet P., Ruf M.-T., Gramiccia M., Varani S., Chicharro C., Bart A., Harms G., Chiodini P.L., Brekke H., Robert-Gangneux F., Cortes S., Verweij J.J., Scarabello A., Karlsson Sobirk S., Guery R., van Henten S., Di Muccio T., Carra E., van Thiel P., Vandeputte M., Gaspari V., Blum J., APH - Global Health, Infectious diseases, AII - Infectious diseases, Chard-Hutchinson, Xavier, Institute of Tropical Medicine [Antwerp] (ITM), Public Health Agency of Sweden, CHU Necker - Enfants Malades [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), University of Basel (Unibas), Istituto Superiore di Sanita [Rome], Azienda Ospedaliero Universitaria A. Meyer [Firenze, Italy], Instituto de Salud Carlos III [Madrid] (ISC), Amsterdam UMC - Amsterdam University Medical Center, Charité - UniversitätsMedizin = Charité - University Hospital [Berlin], University College London Hospitals (UCLH), Oslo University Hospital [Oslo], Institut de recherche en santé, environnement et travail (Irset), Université d'Angers (UA)-Université de Rennes (UR)-École des Hautes Études en Santé Publique [EHESP] (EHESP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique ), École des Hautes Études en Santé Publique [EHESP] (EHESP), Universidade Nova de Lisboa = NOVA University Lisbon (NOVA), National Institute for Infectious Diseases 'Lazzaro Spallanzani', Lund University [Lund], Hôpital privé du Confluent [Nantes], Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna 'Bruno Ubertini' (IZSLER), and Istituto Superiore di Sanità (ISS)

Subjects
Adult, Male, Adolescent, Epidemiology, [SDV]Life Sciences [q-bio], Leishmaniasis, Cutaneous, imported, authochthonou, Young Adult, Virology, Humans, Authochthonous, Child, Leishmaniasis, leishmaniasis, travel, Aged, Retrospective Studies, Aged, 80 and over, Leishmania, Travel, Surveillance, Public Health, Environmental and Occupational Health, Infant, Newborn, Infant, Middle Aged, leishmaniasi, [SDV] Life Sciences [q-bio], Europe, Imported, Child, Preschool, surveillance, Leishmaniasis, Visceral, Female, authochthonous
Abstract

Background Surveillance of human leishmaniasis in Europe is mostly limited to country-specific information from autochthonous infections in the southern part. As at the end of 2021, no integrated analysis has been performed for cases seen across centres in different European countries. Aim To provide a broad perspective on autochthonous and imported leishmaniasis cases in endemic and non-endemic countries in Europe. Methods We retrospectively collected records from cutaneous, mucosal and visceral leishmaniasis cases diagnosed in 15 centres between 2014 and 2019. Centres were located in 11 countries: Belgium, France, Germany, Italy, the Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. Data on country of infection, reason for travelling, infecting species, age and sex were analysed. Results We obtained diagnostic files from 1,142 cases, of which 76%, 21% and 3% had cutaneous, visceral, and mucosal disease, respectively. Of these, 68% were men, and 32% women, with the median age of 37 years (range: 0–90) at diagnosis. Visceral leishmaniasis was mainly acquired in Europe (88%; 167/190), while cutaneous leishmaniasis was primarily imported from outside Europe (77%; 575/749). Sixty-two percent of cutaneous leishmaniasis cases from outside Europe were from the Old World, and 38% from the New World. Geographic species distribution largely confirmed known epidemiology, with notable exceptions. Conclusions Our study confirms previous reports regarding geographic origin, species, and traveller subgroups importing leishmaniasis into Europe. We demonstrate the importance of pooling species typing data from many centres, even from areas where the aetiology is presumably known, to monitor changing epidemiology.

Published
2022

45. Lehren aus der Covid-19-Pandemie: Der Weg zu größerer Resilienz im deutschen Gesundheitssystem

Author

Benstetter, Franz, Blum, Johannes, Dorn, Florian, Greß, Stefan, Heuer, Axel, Jesberger, Christian, Jochimsen, Beate, Schmidt, Christoph M., Schreyögg, Jonas, Pimpertz, Jochen, and Wuppermann, Amelie

Subjects
I18, I11, Gesundheitswesen, Gesundheitsversorgung, Gesetzliche Krankenversicherung, ddc:330, Gesundheitsfinanzierung, Coping-Strategie, Gesundheitspolitik, Epidemie, Deutschland
Abstract

Ein Kollaps der Krankenhäuser und insbesondere der Intensivstationen konnte während der Covid-19-Krise in den vergangenen zwei Jahren vermieden werden. Allerdings hat die Pandemie grundlegende Probleme des deutschen Gesundheitssystems offengelegt. Es war nicht auf die Krise vorbereitet: Relevante Informationen zum Infektionsgeschehen standen weder zeitnah noch im erforderlichen Umfang zur Verfügung, da das deutsche Gesundheitswesen im internationalen Vergleich bei der Digitalisierung hinterherhinkt. Dazu kamen die Defizite in der Finanzierung der gesetzlichen Krankenkassen, der Reformbedarf der Krankenhausstruktur und vor allem der Mangel an Pflegepersonal. Unsere Autoren diskutieren im aktuellen Schnelldienst, wie sich das Gesundheitssystem in Zukunft resilienter und gleichzeitig leistungsfähiger gestalten ließe. Wie kann die Beitragsfinanzierung zur gesetzlichen Krankenversicherung auf eine stabile Grundlage gestellt werden? Ist es sinnvoll, den Wettbewerb zwischen den Krankkassen zu stärken, um nicht-medizinisch notwendige Behandlungen zu vermeiden? Unsere Autoren zeigen zudem, dass eine Strukturbereinigung im Krankenhaussektor, die die Anzahl der Kliniken verringert und medizinische Leistungen und Behandlungsangebote bündelt, Kosten sparen, das Pflegepersonal entlasten und Über­kapazitäten abbauen könnte. Ergänzend sollten ambulante Behandlungszentren aufgebaut werden, die auch kleiner OPs durchführen könnten. Notwendig ist es auch, relevante Informationen zeitnah zur Verfügung zu stellen. Die Einführung einer elektronischen Patientenakte und der Aufbau eines Forschungsdatenzentrums Gesundheit könnte es erlauben, umfassendere Daten aus dem Gesundheitssystem schneller zusammenzuführen und auszuwerten.

Published
2022

47. Fission: Practical algorithms for computing minimum balanced node separators.

Author

Blum, Johannes, Li, Ruoying, and Storandt, Sabine

Subjects
*GRAPH algorithms, *UNDIRECTED graphs, *ALGORITHMS, *GRAPH connectivity, *DATA structures, PLANNING techniques
Abstract

Given an undirected graph, a balanced node separator is a set of nodes whose removal splits the graph into connected components of limited size. Balanced node separators are used for graph partitioning, for the construction of graph data structures, and for measuring network reliability. It is NP-hard to decide whether a graph has a balanced node separator of size at most k. Therefore, practical algorithms typically try to find small separators in a heuristic fashion. In this paper, we present a branching algorithm that for a given value k either outputs a balanced node separator of size at most k or certifies that k is a valid lower bound. Using this algorithm iteratively for growing values of k allows us to find a minimum balanced node separator. To make this algorithm scalable to real-world (road) networks of considerable size, we first describe pruning rules to reduce the graph size without affecting the minimum balanced separator size. In addition, we prove several structural properties of minimum balanced node separators which are then used to reduce the branching factor and search depth of our algorithm. We experimentally demonstrate the applicability of our algorithm to graphs with thousands of nodes and edges. We showcase the usefulness of having minimum balanced separators for judging the quality of existing heuristics, for improving preprocessing-based route planning techniques on road networks, and for lower bounding important graph parameters. Finally, we discuss how our ideas and methods can also be leveraged to accelerate the heuristic computation of balanced node separators. [ABSTRACT FROM AUTHOR]

Published
2022
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