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Improvement of Some Hayashi–Ostrowski Type Inequalities with Applications in a Probability Setting

Mohammad W. Alomari, Christophe Chesneau, Víctor Leiva, Carlos Martin-Barreiro
2022 Mathematics  
In this paper, we introduce improvements to some Ostrowski type inequalities and present their corresponding proofs.  ...  In 1938, Ostrowski [14] established an interesting inequality for differentiable functions with bounded derivatives as follows.  ...  Concluding Remarks In this paper, we have stated and proved refinements as well as introduced improvements to some Ostrowski type inequalities.  ... 
doi:10.3390/math10132316 fatcat:5jg3e6fiqbd65b4nchorbctbpq

Diseases of Free-Ranging Snow Leopards and Primary Prey Species [chapter]

Stéphane Ostrowski, Martin Gilbert
2016 Snow Leopards  
Ostrowski and Inayat Ali.  ...  Caprine mycoplasmosis/2010/Pamiralai Mountains/Tajikistan/ostrowski et al., 2011.  ... 
doi:10.1016/b978-0-12-802213-9.00009-2 fatcat:ngej4mgvvvfdjlmbefb6pownqu

Engineering an Incremental ASP Solver [chapter]

Martin Gebser, Roland Kaminski, Benjamin Kaufmann, Max Ostrowski, Torsten Schaub, Sven Thiele
2008 Lecture Notes in Computer Science  
Many real-world applications, like planning or model checking, comprise a parameter reflecting the size of a solution. In a propositional formalism like Answer Set Programming (ASP), such problems can only be dealt with in a bounded way, considering one problem instance after another by gradually increasing the bound on the solution size. We thus propose an incremental approach to both grounding and solving in ASP. Our goal is to avoid redundancy by gradually processing the extensions to a
more » ... em rather than repeatedly re-processing the entire (extended) problem. We start by furnishing a formal framework capturing our incremental approach in terms of module theory. In turn, we take advantage of this framework for guiding the successive treatment of program slices during grounding and solving. Finally, we describe the first integrated incremental ASP system, iclingo, and provide an experimental evaluation.
doi:10.1007/978-3-540-89982-2_23 fatcat:6sofhn4knjeqjkl6erq6dn45ri

Rhometa: Population recombination rate estimation from metagenomic read datasets [article]

Sidaswar Krishnan, Matthew Z DeMaere, Dominik Beck, Martin Ostrowski, Justin R Seymour, Aaron E Darling
2022 bioRxiv   pre-print
Bacterial evolution is influenced by the exchange of genetic information between species through a process referred to as recombination. The rate of recombination is a useful measure for the adaptive capacity of a bacterial population. We introduce Rhometa (https://github.com/sid-krish/Rhometa), a new software package to determine recombination rates from shotgun sequencing reads of metagenomes.It extends the composite likelihood approach for population recombination rate estimation and enables
more » ... the analysis of modern short-read datasets. We evaluated Rhometa over a broad range of sequencing depths and complexities, using simulated and real experimental short-read data aligned to external reference genomes. In simulated datasets, the deviation from the expected value decreased as the number of genomes increased and we show that 80 genomes are sufficient to reduce these variations below 30%. Testing on an S. pneumoniae transformation experiment dataset we show that Rhometa accurately estimate the expected levels of recombination in a real world dataset.
doi:10.1101/2022.08.04.502887 fatcat:w6fv4bwgwfefnhvpjbsklw3pbe

The inefficiency of the first-order Fermi process in UHECR production at relativistic shocks [article]

Jacek Niemiec, Michal Ostrowski, Martin Pohl
2007 arXiv   pre-print
of the origin of ultra-high-energy cosmic rays at relativistic shock waves is discussed in the light of results of recent Monte Carlo studies of the first-order Fermi particle acceleration (Niemiec & Ostrowski  ... 
arXiv:0705.4453v1 fatcat:dzcjpxhopvdnhosg6bh27cdnze

Multi-locus sequence analysis, taxonomic resolution and biogeography of marine Synechococcus

Sophie Mazard, Martin Ostrowski, Frédéric Partensky, David J. Scanlan
2011 Environmental Microbiology  
Ostrowski, M. et al. (2010) PtrA is required for coordinate regulation of gene expression during phosphate stress in a marine Synechococcus. ISME J. 4, 908-921. 15.  ... 
doi:10.1111/j.1462-2920.2011.02514.x pmid:21651684 fatcat:afn5aqf5ovcfxnaapuch2t76ru

Virological Sampling of Inaccessible Wildlife with Drones

Jemma Geoghegan, Vanessa Pirotta, Erin Harvey, Alastair Smith, Jan Buchmann, Martin Ostrowski, John-Sebastian Eden, Robert Harcourt, Edward Holmes
2018 Viruses  
There is growing interest in characterizing the viromes of diverse mammalian species, particularly in the context of disease emergence. However, little is known about virome diversity in aquatic mammals, in part due to difficulties in sampling. We characterized the virome of the exhaled breath (or blow) of the Eastern Australian humpback whale (Megaptera novaeangliae). To achieve an unbiased survey of virome diversity, a meta-transcriptomic analysis was performed on 19 pooled whale blow samples
more » ... collected via a purpose-built Unmanned Aerial Vehicle (UAV, or drone) approximately 3 km off the coast of Sydney, Australia during the 2017 winter annual northward migration from Antarctica to northern Australia. To our knowledge, this is the first time that UAVs have been used to sample viruses. Despite the relatively small number of animals surveyed in this initial study, we identified six novel virus species from five viral families. This work demonstrates the potential of UAVs in studies of virus disease, diversity, and evolution.
doi:10.3390/v10060300 pmid:29865228 pmcid:PMC6024715 fatcat:n5tvp7mojnehvcnwm4d55czqdi

Nanotoxicology: characterizing the scientific literature, 2000–2007

Alexis D. Ostrowski, Tyronne Martin, Joseph Conti, Indy Hurt, Barbara Herr Harthorn
2008 Journal of nanoparticle research  
Understanding the toxicity of nanomaterials and nano-enabled products is important for human and environmental health and safety as well as public acceptance. Assessing the state of knowledge about nanotoxicology is an important step in promoting comprehensive understanding of the health and environmental implications of these new materials. To this end, we employed bibliometric techniques to characterize the prevalence and distribution of the current scientific literature. We found that the
more » ... o-toxicological literature is dispersed across a range of disciplines and sub-fields; focused on in vitro testing; often does not specify an exposure pathway; and tends to emphasize acute toxicity and mortality rather than chronic exposure and morbidity. Finally, there is very little research on consumer products, particularly on their environmental fate, and most research is on the toxicity of basic nanomaterials. The implications for toxicologists, regulators and social scientists studying nanotechnology and society are discussed.
doi:10.1007/s11051-008-9579-5 pmid:21170129 pmcid:PMC2988215 fatcat:jkeedapcxfc55p7py462ykj5di

Towards an Ecological Trait-data Standard [article]

Florian D Schneider, Malte Jochum, Gaëtane Le Provost, Andreas Ostrowski, Caterina Penone, David Fichtmüller, Anton Güntsch, Martin M. Gossner, Birgitta König-Ries, Pete Manning, Nadja K. Simons
2018 biorxiv/medrxiv   pre-print
Trait-based approaches are widespread throughout ecological research, offering great potential for trait data to deliver general and mechanistic conclusions. Accordingly, a wealth of trait data is available for many organism groups, but, due to a lack of standardisation, these data come in heterogeneous formats. We review current initiatives and infrastructures for standardising trait data and discuss the importance of standardisation for trait data hosted in distributed open-access
more » ... . In order to facilitate the standardisation and harmonisation of distributed trait datasets, we propose a general and simple vocabulary as well as a simple data structure for storing and sharing ecological trait data. Additionally, we provide an R-package that enables the transformation of any tabular dataset into the proposed format. This also allows trait datasets from heterogeneous sources to be harmonised and merged, thus facilitating data compilation for any particular research focus. With these decentralised tools for trait-data harmonisation, we intend to facilitate the exchange and analysis of trait data within ecological research and enable global syntheses of traits across a wide range of taxa and ecosystems.
doi:10.1101/328302 fatcat:6mpklbvzy5fcnmk7oubxzvxarm

An Economical Custom-Built Drone for Assessing Whale Health

Vanessa Pirotta, Alastair Smith, Martin Ostrowski, Dylan Russell, Ian D. Jonsen, Alana Grech, Robert Harcourt
2017 Frontiers in Marine Science  
10.1093/bioinformatics/btt593 PubMed Abstract | CrossRef Full Text | Google Scholar Keywords: UAV, UAS, drone, blow, humpback whale, microbiota, technology, conservation Citation: Pirotta V, Smith A, Ostrowski  ...  National Oceanic and Atmospheric Administration (NOAA), United States Reviewed by: Nuno Queiroz, University of Porto, Portugal Gail Schofield, Deakin University, Australia Copyright © 2017 Pirotta, Smith, Ostrowski  ... 
doi:10.3389/fmars.2017.00425 fatcat:ozswyacdifa4foq4psty7e45o4

Stochastic Delay Prediction in Large Train Networks

Annabell Berger, Andreas Gebhardt, Matthias Müller-Hannemann, Martin Ostrowski, Marc Herbstritt
2011 Algorithmic Approaches for Transportation Modeling, Optimization, and Systems  
In daily operation, railway traffic always deviates from the planned schedule to a certain extent. Primary initial delays of trains may cause a whole cascade of secondary delays of other trains over the entire network. In this paper, we propose a stochastic model for delay propagation and forecasts of arrival and departure events which is applicable to all kind of public transport (not only to railway traffic). Our model is fairly realistic, it includes general waiting policies (how long do
more » ... ns wait for delayed feeder trains), it uses driving time profiles (discrete distributions) on travel arcs which depend on the departure time, and it incorporates the catch-up potential of buffer times on driving sections and train stops. The model is suited for an online scenario where a massive stream of update messages on the current status of trains arrives which has to be propagated through the whole network. Efficient stochastic propagation of delays has important applications in online timetable information, in delay management and train disposition, and in stability analysis of timetables. The proposed approach has been implemented and evaluated on the German timetable of 2011 with waiting policies of Deutsche Bahn AG. A complete stochastic delay propagation for the whole German train network and a whole day can be performed in less than 14 seconds on a PC. We tested our propagation algorithm with artificial discrete travel time distributions which can be parametrized by the size of their fluctuations. Our forecasts are compared with real data. It turns out that stochastic propagation of delays is efficient enough to be applicable in practice, but the forecast quality requires further adjustments of our artificial travel time distributions to estimates from real data.
doi:10.4230/oasics.atmos.2011.100 dblp:conf/atmos/BergerGMO11 fatcat:pn5quwvncvdb5gutjzwliacijm

Theory Solving Made Easy with Clingo 5

Martin Gebser, Roland Kaminski, Benjamin Kaufmann, Max Ostrowski, Torsten Schaub, Philipp Wanko, Marc Herbstritt
2016 International Conference on Logic Programming  
Answer Set Programming (ASP) is a model, ground, and solve paradigm. The integration of application-or theory-specific reasoning into ASP systems thus impacts on many if not all elements of its workflow, viz. input language, grounding, intermediate language, solving, and output format. We address this challenge with the fifth generation of the ASP system clingo and its grounding and solving components by equipping them with well-defined generic interfaces facilitating the manifold integration
more » ... forts. On the grounder's side, we introduce a generic way of specifying language extensions and propose an intermediate format accommodating their ground representation. At the solver end, this is accompanied by high-level interfaces easing the integration of theory propagators dealing with these extensions.
doi:10.4230/oasics.iclp.2016.2 dblp:conf/iclp/GebserKKOSW16 fatcat:eghghg7wwfemdifoznoloszkie

Efficient CO2 fixation by surface Prochlorococcus in the Atlantic Ocean

Manuela Hartmann, Paola Gomez-Pereira, Carolina Grob, Martin Ostrowski, David J Scanlan, Mikhail V Zubkov
2014 The ISME Journal  
Nearly half of the Earth's surface is covered by the ocean populated by the most abundant photosynthetic organisms on the planet-Prochlorococcus cyanobacteria. However, in the oligotrophic open ocean, the majority of their cells in the top half of the photic layer have levels of photosynthetic pigmentation barely detectable by flow cytometry, suggesting low efficiency of CO 2 fixation compared with other phytoplankton living in the same waters. To test the latter assumption, CO 2 fixation rates
more » ... of flow cytometrically sorted 14 C-labelled phytoplankton cells were directly compared in surface waters of the open Atlantic Ocean (301S to 301N). CO 2 fixation rates of Prochlorococcus are at least 1.5-2.0 times higher than CO 2 fixation rates of the smallest plastidic protists and Synechococcus cyanobacteria when normalised to photosynthetic pigmentation assessed using cellular red autofluorescence. Therefore, our data indicate that in oligotrophic oceanic surface waters, pigment minimisation allows Prochlorococcus cells to harvest plentiful sunlight more effectively than other phytoplankton.
doi:10.1038/ismej.2014.56 pmid:24763372 pmcid:PMC4992072 fatcat:ik7mbjjdvrd4pph2orj6afnemi

E2f1–3 Are Critical for Myeloid Development

Prashant Trikha, Nidhi Sharma, Rene Opavsky, Andres Reyes, Clarissa Pena, Michael C. Ostrowski, Martine F. Roussel, Gustavo Leone
2010 Journal of Biological Chemistry  
Hematopoietic development involves the coordinated activity of differentiation and cell cycle regulators. In current models of mammalian cell cycle control, E2f activators (E2f1, E2f2, and E2f3) are portrayed as the ultimate transcriptional effectors that commit cells to enter and progress through S phase. Using conditional gene knock-out strategies, we show that E2f1-3 are not required for the proliferation of early myeloid progenitors. Rather, these E2fs are critical for cell survival and
more » ... iferation at two distinct steps of myeloid development. First, E2f1-3 are required as transcriptional repressors for the survival of CD11b ؉ myeloid progenitors, and then they are required as activators for the proliferation of CD11b ؉ macrophages. In bone marrow macrophages, we show that E2f1-3 respond to CSF1-Myc mitogenic signals and serve to activate E2f target genes and promote their proliferation. Together, these findings expose dual functions for E2f1-3 at distinct stages of myeloid development in vivo, first as repressors in cell survival and then as activators in cell proliferation. In summary, this work places E2f1-3 in a specific signaling cascade that is critical for myeloid development in vivo. Downloaded from FIGURE 3. E2f1-3 are required for BMM proliferation. A, RT-PCR analysis of E2fs and E2f target genes on BMMs at the indicated time points. The values on the y axis represent -fold induction. B, BMMs were plated at a density of 1 ϫ 10 5 cells/60-mm plate. Cells were grown in a medium containing 50 ng/ml CSF-1 and were harvested and counted every 24 h for 4 days (left). Cells were harvested for BrdU incorporation. Cells were stained with anti-BrdU antibody and counterstained with DAPI, and BrdU-positive cells were counted as described under "Experimental Procedures" (right). C, bright field images of vectoror cre-treated E2f1 Ϫ/Ϫ 2 Ϫ/Ϫ 3 f/f BMMs at 10ϫ magnification. D, E2f3 PCR genotyping on genomic DNA isolated from cre-treated E2f1 Ϫ/Ϫ E2f2 Ϫ/Ϫ E2f3 f/f BMMs. E, FACS analysis of BrdU ϩ Cd11b ϩ cells of the indicated genotypes. F, BMMs from E2f1 ϩ/ϩ 2 ϩ/ϩ 3 ϩ/ϩ and E2f1 Ϫ/Ϫ 2 Ϫ/Ϫ 3 f/f mice were infected with either vector-or cre-expressing retroviruses. BMMs were co-stained with Cd11b and BrdU and analyzed by FACS. The graph depicts the percentage of Cd11b ϩ cells that are also positive for BrdU. Values are mean Ϯ S.D. (error bars) (p Ͻ 0.006).
doi:10.1074/jbc.m110.182733 pmid:21115501 pmcid:PMC3039366 fatcat:mxmahkw63ve3hkvavguplv3rwq

aspartame: Solving Constraint Satisfaction Problems with Answer Set Programming [chapter]

Mutsunori Banbara, Martin Gebser, Katsumi Inoue, Max Ostrowski, Andrea Peano, Torsten Schaub, Takehide Soh, Naoyuki Tamura, Matthias Weise
2015 Lecture Notes in Computer Science  
Encoding finite linear CSPs as Boolean formulas and solving them by using modern SAT solvers has proven to be highly effective by the award-winning sugar system. We here develop an alternative approach based on ASP that serves two purposes. First, it provides a library for solving CSPs as part of an encompassing logic program. Second, it furnishes an ASP-based CP solver similar to sugar. Both tasks are addressed by using first-order ASP encodings that provide us with a high degree of
more » ... , either for integration within ASP or for easy experimentation with different implementations. When used as a CP solver, the resulting system aspartame re-uses parts of sugar for parsing and normalizing CSPs. The obtained set of facts is then combined with an ASP encoding that can be grounded and solved by off-the-shelf ASP systems. We establish the competitiveness of our approach by empirically contrasting aspartame and sugar.
doi:10.1007/978-3-319-23264-5_10 fatcat:kxvakstwtbf6xdv66w5ihqlbgq
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