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Context-free commutative grammars with integer counters and resets

Dmitry Chistikov, Christoph Haase, Simon Halfon
2018 Theoretical Computer Science  
We study the computational complexity of reachability, coverability and inclusion for extensions of context-free commutative grammars with integer counters and reset operations on them. Those grammars can alternatively be viewed as an extension of communication-free Petri nets. Our main results are that reachability and coverability are inter-reducible and both NPcomplete. In particular, this class of commutative grammars enjoys semilinear reachability sets. We also show that the inclusion
more » ... em is, in general, coNEXP-complete and already Π P 2 -complete for grammars with only one non-terminal symbol. Showing the lower bound for the latter result requires us to develop a novel Π P 2 -complete variant of the classic subset sum problem.
doi:10.1016/j.tcs.2016.06.017 fatcat:kkcyianwrzbghkcbrfmofxl2mu

Context-Free Commutative Grammars with Integer Counters and Resets [article]

Dmitry Chistikov, Christoph Haase, Simon Halfon
2016 arXiv   pre-print
We study the computational complexity of reachability, coverability and inclusion for extensions of context-free commutative grammars with integer counters and reset operations on them. Those grammars can alternatively be viewed as an extension of communication-free Petri nets. Our main results are that reachability and coverability are inter-reducible and both NP-complete. In particular, this class of commutative grammars enjoys semi-linear reachability sets. We also show that the inclusion
more » ... blem is, in general, coNEXP-complete and already Π_2^P-complete for grammars with only one non-terminal symbol. Showing the lower bound for the latter result requires us to develop a novel Π_2^P-complete variant of the classic subset sum problem.
arXiv:1511.04893v2 fatcat:s4oz5hconbextbxx5urudqzraa

The Ideal Approach to Computing Closed Subsets in Well-Quasi-Ordering [article]

Jean Goubault-Larrecq and Simon Halfon and Prateek Karandikar and K. Narayan Kumar and Philippe Schnoebelen
2019 arXiv   pre-print
Halfon, P. Karandikar, K. Narayan Kumar, and Ph. Schnoebelen J. Goubault-Larrecq, S. Halfon, P. Karandikar, K. Narayan Kumar, and Ph. Schnoebelen J. Goubault-Larrecq, S. Halfon, P.  ...  Halfon, P. Karandikar, K. Narayan Kumar, and Ph. Schnoebelen J. Goubault-Larrecq, S. Halfon, P. Karandikar, K. Narayan Kumar, and Ph. Schnoebelen J. Goubault-Larrecq, S. Halfon, P.  ... 
arXiv:1904.10703v1 fatcat:k4e7wpm3nrhwpdml7bro5xt4s4

Infinitary Noetherian Constructions II. Transfinite Words and the Regular Subword Topology [article]

Jean Goubault-Larrecq, Simon Halfon, Aliaume Lopez
2022 arXiv   pre-print
We show that the spaces of transfinite words, namely ordinal-indexed words, over a Noetherian space, is also Noetherian, under a natural topology which we call the regular subword topology. We characterize its sobrification and its specialization ordering, and we give an upper bound on its dimension and on its stature.
arXiv:2202.05047v2 fatcat:j5fuqiuyvrd7vhodqwjxdzqd3q

Integer Vector Addition Systems with States [chapter]

Christoph Haase, Simon Halfon
2014 Lecture Notes in Computer Science  
This paper studies reachability, coverability and inclusion problems for Integer Vector Addition Systems with States (ZVASS) and extensions and restrictions thereof. A ZVASS comprises a finite-state controller with a finite number of counters ranging over the integers. Although it is folklore that reachability in ZVASS is NP-complete, it turns out that despite their naturalness, from a complexity point of view this class has received little attention in the literature. We fill this gap by
more » ... ing an in-depth analysis of the computational complexity of the aforementioned decision problems. Most interestingly, it turns out that while the addition of reset operations to ordinary VASS leads to undecidability and Ackermann-hardness of reachability and coverability, respectively, they can be added to ZVASS while retaining NP-completness of both coverability and reachability.
doi:10.1007/978-3-319-11439-2_9 fatcat:7pvckuxbvzfrvkecxg2wqrkaum

Decidability, Complexity, and Expressiveness of First-Order Logic Over the Subword Ordering [article]

Simon Halfon, Philippe Schnoebelen, Georg Zetzsche
2021 arXiv   pre-print
We consider first-order logic over the subword ordering on finite words, where each word is available as a constant. Our first result is that the Σ_1 theory is undecidable (already over two letters). We investigate the decidability border by considering fragments where all but a certain number of variables are alternation bounded, meaning that the variable must always be quantified over languages with a bounded number of letter alternations. We prove that when at most two variables are not
more » ... nation bounded, the Σ_1 fragment is decidable, and that it becomes undecidable when three variables are not alternation bounded. Regarding higher quantifier alternation depths, we prove that the Σ_2 fragment is undecidable already for one variable without alternation bound and that when all variables are alternation bounded, the entire first-order theory is decidable.
arXiv:1701.07470v2 fatcat:zkrsawlwfvdqnkbepnaz2wjxxm

Re-evaluating microglia expression profiles using RiboTag and cell isolation strategies

Zhana Haimon, Alon Volaski, Johannes Orthgiess, Sigalit Boura-Halfon, Diana Varol, Anat Shemer, Simon Yona, Binyamin Zuckerman, Eyal David, Louise Chappell-Maor, Ingo Bechmann, Martin Gericke (+2 others)
2018 Nature Immunology  
Transcriptome profiling is widely used to infer functional states of specific cell types, as well as their responses to stimuli, to define contributions to physiology and pathophysiology. Focusing on microglia, the brain's macrophages, we report here a side-by-side comparison of classical cell-sorting-based transcriptome sequencing and the 'RiboTag' method, which avoids cell retrieval from tissue context and yields translatome sequencing information. Conventional whole-cell microglial
more » ... omes were found to be significantly tainted by artifacts introduced by tissue dissociation, cargo contamination and transcripts sequestered from ribosomes. Conversely, our data highlight the added value of RiboTag profiling for assessing the lineage accuracy of Cre recombinase expression in transgenic mice. Collectively, this study indicates method-based biases, reveals observer effects and establishes RiboTag-based translatome profiling as a valuable complement to standard sorting-based profiling strategies.
doi:10.1038/s41590-018-0110-6 pmid:29777220 pmcid:PMC5986066 fatcat:aipdgttbpndz5ftazs7kchs7q4

Dicer Deficiency Differentially Impacts Microglia of the Developing and Adult Brain

Diana Varol, Alexander Mildner, Thomas Blank, Anat Shemer, Neta Barashi, Simon Yona, Eyal David, Sigalit Boura-Halfon, Yifat Segal-Hayoun, Louise Chappell-Maor, Hadas Keren-Shaul, Dena Leshkowitz (+6 others)
2017 Immunity  
Varol et al. 2 SUMMARY Microglia seed the embryonic neuro-epithelium, expand and actively sculpt neuronal circuits in the developing CNS, but eventually adopt relative quiescence and ramified morphology in the adult. Here we probed the impact of post-transcriptional control by microRNAs (miRNAs) on microglial performance during development and adulthood by generating mice lacking microglial dicer expression at these distinct stages. Conditional Dicer ablation in adult microglia revealed that
more » ... NAs were required to limit microglial responses to challenge. Specifically, following peripheral endotoxin exposure, Dicer-deficient microglia overexpressed pro-inflammatory cytokines and as a result, impaired hippocampal neuronal functions. In contrast, prenatal ablation resulted in spontaneous microglia activation and revealed Dicer involvement in DNA repair and preservation of genome integrity. Accordingly, Dicer-deficiency rendered otherwise radio-resistant microglia sensitive to gamma-irradiation. Collectively, the differential impact of the Dicer ablation on microglia of the developing and adult brain highlights the changes these cells undergo with time. Highlights  miRNAs curb activation of adult microglia following challenge  Microglia hyper-activation results in acute impairment of hippocampal neuronal functions  Proliferative Dicer-deficient microglia in the developing brain accumulate DNA damage  Microglia of developing and adult brain are highly distinct Varol et al.
doi:10.1016/j.immuni.2017.05.003 pmid:28636953 fatcat:dnfo3bz7rvch7hjuyqk2i3jbhi

On Büchi One-Counter Automata

Stanislav Böhm, Stefan Göller, Simon Halfon, Piotr Hofman
unpublished
Equivalence of deterministic pushdown automata is a famous problem in theoretical computer science whose decidability has been shown by Sénizergues. Our first result shows that decidability no longer holds when moving from finite words to infinite words. This solves an open problem that has recently been raised by Löding. In fact, we show that already the equivalence problem for deterministic Büchi one-counter automata is undecidable. Hence, the decidability border is rather tight when taking
more » ... to account a recent result by Löding and Repke that equivalence of deterministic weak parity pushdown automata (a subclass of deterministic Büchi pushdown automata) is decidable. Another known result on finite words is that the universality problem for vector addition systems is decidable. We show undecidability when moving to infinite words. In fact, we prove that already the universality problem for nondeterministic Büchi one-counter nets (or equivalently vector addition systems with one unbounded dimension) is undecidable.
fatcat:2pxob5qxnna2fm4acizsqolvzy

COVID19 and acute lymphoblastic leukemias of children and adolescents: first recommendations of the Leukemia committee of the French Society for the fight against Cancers and Leukemias in children and adolescents (SFCE)

André Baruchel, Yves Bertrand, Nicolas Boissel, Benoit Brethon, Stéphane Ducassou, Virginie Gandemer, Carine Halfon-Domenech, Thierry Leblanc, Guy Leverger, Gérard Michel, Arnaud Petit, Anne-France Ray-Lunven (+4 others)
2020 Bulletin du Cancer  
2 , Thierry Leblanc 1 , Guy Leverger 6 , Gérard Michel 7 , Arnaud Petit 6 , Anne-France Ray-Lunven 1 , Pierre-Simon Rohrlich 8 , Pascale Schneider 9 , Nicolas Sirvent 10 , Marion Strullu 1 , for the SFCE  ...  fight against Cancers and Leukemias in children and adolescents (SFCE) André Baruchel 1 , Yves Bertrand 2 , Nicolas Boissel 3 , Benoit Brethon 1 , Stéphane Ducassou 4 , Virginie Gandemer 5 , Carine Halfon-Domenech  ... 
doi:10.1016/j.bulcan.2020.04.003 pmid:32387061 pmcid:PMC7190519 fatcat:fqxvg7v7kjcazihtmf7joggeza

Page 499 of AIDS Care Vol. 19, Issue 4 [page]

2007 AIDS Care  
Periard, D., Telenti, A., Sudre, P., Cheseaux, J.J., Halfon, P., Reymond, M.J., Marcovina, $.M., Glauser, M.P., Nicod, P., Darioli, R., & Mooser, V. (1999).  ...  ., Simon, A., Partisani, M., & Costagliola, D. (2003). Increased risk of myocardial infarction with duration of protease inhibitor therapy in HIV-infected men. AIDS, 17, 2479-86.  ... 

Page 468 of Jewish Quarterly Review Vol. 13, Issue [page]

1901 Jewish Quarterly Review  
M.,253) seems to be a proper name ; and so “ Halfon b. Saadia b. David al-Tawili,” ibid., p.66 b, MS. Or. 1470. (P. 128) n. 286%. p3(bx), Ja‘hja, Br. M., 116 b.  ...  Simon, MS. Fischl-Hirsch, Catal., Berlin, 1899, n. 227. (P. 127, and XII, p. 132, n. 284. p2>5 and pabdn), Isak b. Kh. is older than Samuel ha-Nagid, according to Sen. Sachs, ha-Goren, I, 36.  ... 

Page 56 of American Society of Civil Engineers. Collected Journals Vol. 110, Issue 1 [page]

1984 American Society of Civil Engineers. Collected Journals  
L., and Simons, T.  ...  ., and Halfon, E., “Model of Primary Production Including Cir- culation Influences in Lake Superior,” Applied Mathematical Modeling, Vol. 2, No. 1, Mar., 1978, pp. 34—40. . Lam, D. C.  ... 

Impact on the Fate of Toxic Contaminants in the Toronto Waterfront — Should the Toronto Main Sewage Treatment Plant Outfall Be Moved Farther Offshore?

Efraim Halfon
2001 Water quality research journal of Canada  
Simons, as well as an anonymous referee who provided enhancement to the text. M. Griffiths carefully reviewed an early draft and provided useful comments.  ...  Simons and Schertzer (1989) described the local cur-rents, and Greenwood and McGillivray (1978) explained the influence of waves on the littoral zone.  ...  A mathematical model, TOXFATE (Halfon 1986a,b; Halfon and Oliver 1990; Halfon and Allan 1995) was used to integrate the information about the contaminant loadings from the STPs and tributaries in the  ... 
doi:10.2166/wqrj.2001.002 fatcat:webcpu2aijfqbpowg6pfiyzcrm

Page 534 of Jewish Quarterly Review Vol. 15, Issue [page]

1903 Jewish Quarterly Review  
Resp., 116, X, 2, pp. — Hallévi, nrp, 368 ec. — Menahem Halfon (1535). 480, 2. —b. Isaac of Carcassonne (14th c.). mpvonn ’p, 134. — yn of Mantua. Calendar notes, 479, 28 ¢. — Hayy b.  ...  Simon (14th c.). npn, 180, 154 —b. Solomon (16th c.). ~Resp., 480 — Sopino (14-15th c.). cD npn, Elijah Aaron Lattes (1834). Letter, 176; Poem, 388. — b. Abraham (15th c.); Letters, 468, I. — b.  ... 
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