1,602 research outputs found
Avoidability of formulas with two variables
In combinatorics on words, a word over an alphabet is said to
avoid a pattern over an alphabet of variables if there is no
factor of such that where is a
non-erasing morphism. A pattern is said to be -avoidable if there exists
an infinite word over a -letter alphabet that avoids . We consider the
patterns such that at most two variables appear at least twice, or
equivalently, the formulas with at most two variables. For each such formula,
we determine whether it is -avoidable, and if it is -avoidable, we
determine whether it is avoided by exponentially many binary words
Glutamatergic neurotransmission links sensitivity to volatile anesthetics with mitochondrial function
Actualment, Albert Quintana Romero desenvolupa la seva recerca a l'Institut de Neurociències de la Universitat Autònoma de BarcelonaAn enigma of modern medicine has persisted for over 150 years. The mechanisms by which volatile anesthetics (VAs) produce their effects (loss of consciousness, analgesia, amnesia, and immobility) remain an unsolved mystery. Many attractive putative molecular targets have failed to produce a significant effect when genetically tested in whole-animal models [1-3]. However, mitochondrial defects increase VA sensitivity in diverse organisms from nematodes to humans [4-6]. Ndufs4 knockout (KO) mice lack a subunit of mitochondrial complex I and are strikingly hypersensitive to VAs yet resistant to the intravenous anesthetic ketamine [7]. The change in VA sensitivity is the largest reported for a mammal. Limiting NDUFS4 loss to a subset of glutamatergic neurons recapitulates the VA hypersensitivity of Ndufs4(KO) mice, while loss in GABAergic or cholinergic neurons does not. Baseline electrophysiologic function of CA1 pyramidal neurons does not differ between Ndufs4(KO) and control mice. Isoflurane concentrations that anesthetize only Ndufs4(KO) mice (0.6%) decreased the frequency of spontaneous excitatory postsynaptic currents (sEPSCs) only in Ndufs4(KO) CA1 neurons, while concentrations effective in control mice (1.2%) decreased sEPSC frequencies in both control and Ndufs4(KO) CA1 pyramidal cells. Spontaneous inhibitory postsynaptic currents (sIPSCs) were not differentially affected between genotypes. The effects of isoflurane were similar on evoked field excitatory postsynaptic potentials (fEPSPs) and paired pulse facilitation (PPF) in KO and control hippocampal slices. We propose that CA1 presynaptic excitatory neurotransmission is hypersensitive to isoflurane in Ndufs4(KO) mice due to the inhibition of pre-existing reduced complex I function, reaching a critical reduction that can no longer meet metabolic demands
Спіро[бензо[е]пірано[3,2-с][1,2]оксатіїн-4,3’-індол]-3-карбонітрил 5,5-діоксиди: синтез і вивчення біологічної активності
The development of medicines with several pharmacological activities, including the analgesic, anti-inflammatory and antimicrobial properties, is one of the challenging tasks of modern medicinal chemistry.Aim. To expand the range of novel spiro-condensed derivatives of 1,2-benzoxathiin-4(3H)-one 2,2-dioxide, and study the biological activity of the substances obtained.Results and discussions. The target compounds were synthesized as a result of the interaction of 1,2-benzoxathiin-4(3H)-one 2,2-dioxide, malononitrile and isatins. When using ethyl cyanoacetate the interaction appeared to be much more complicated and requires further research. The study of the biological activity has revealed the compounds with the analgesic properties and the antimicrobial effect against gram-positive strains.Experimental part. Two new 2-amino-2’-oxospiro[4H-pyrano[3,2-c][1,2]benzoxathiine-4,3’-indoline]-3-carbonitrile 5,5-dioxides were synthesized by the three-component reaction based on 1,2-benzoxathiin-4(3H)-one 2,2-dioxide. The anti-inflammatory activity was studied on the model of the carrageenan induced paw edema, and the analgesic activity was assessed on the model of the local inflammatory hyperalgesia. The study of the antimicrobial activity of the compounds obtained was performed by the agar well diffusion method.Conclusions. New spiro[benzo[е]pyrano[3,2-c][1,2]oxathiin-4,3’-indolil]-3-carbonitrile 5,5-dioxides have been synthesized. The compounds obtained have revealed high levels of the analgesic properties and the antimicrobial activity. The latter exceeds the activity of the reference drugs, and has appeared to be higher against grampositive bacteria.Разработка лекарственных средств с несколькими видами фармакологической активности, включая анальгетические, противовоспалительные и антимикробные свойства, является одной из важных задач современной медицинской химии.Цель. Расширить ряд новых спироконденсированных производных 1,2-бензоксатиин-4(3Н)-он 2,2-диоксида и изучить биологическую активность полученных веществ.Результаты и их обсуждение. Целевые соединения были синтезированы в результате взаимодействия 1,2-бензоксатиин-4(3Н)-он 2,2-диоксида, малонодинитрила и изатинов. В случае использования этилцианоацетата в качестве метиленактивного нитрила взаимодействие оказалось значительно более сложным и нуждается в дальнейшем изучении. Исследование биологической активности выявило соединения с анальгетическими свойствами и антимикробным действием в отношении грамположительных штаммов.Экспериментальная часть. Два новых 2-амино-2’-оксоспиро[4Н-пирано[3,2-с][1,2]бензоксатиин-4,3’-индолин]-3-карбонитрил 5,5-диоксида были синтезированы с помощью трехкомпонентной реакции на основе 1,2-бензоксатиин-4(3Н)-он 2,2-диоксида. Противовоспалительную активность изучали на модели карагенин-индуцированного отека, а анальгетическую активность оценивали на модели локальной воспалительной гипералгезии. Было проведено исследование антимикробной активности полученных соединений методом диффузии в агар.Выводы. Синтезированы новые спиро[бензо[е]пирано[3,2-с][1,2]оксатиин-4,3’-индолил]-3-карбонитрил 5,5-диоксиды. Полученные соединения проявили анальгетические свойства и антимикробную активность, которая превышает активность препаратов сравнения и оказалась выше в отношении грамположительных бактерий.Розробка лікарських засобів, що володіють декількома видами фармакологічної активності, включаючи знеболювальну, протизапальну та антимікробну, є одним з важливих завдань сучасної медичної хімії.Мета. Розширити ряд нових спіроконденсованих похідних 1,2-бензоксатіїн-4(3Н)-он 2,2-діоксиду і дослідити біологічну активність одержаних речовин.Результати та їх обговорення. Цільові сполуки були синтезовані в результаті взаємодії 1,2-бензоксатіїн-4(3Н)-он 2,2-діоксиду, малонодинітрилу та ізатинів. У випадку використання етилціаноацетату як метиленактивного нітрилу взаємодія виявилася набагато складнішою і потребує подальших досліджень. Вивчення біологічної активності виявило сполуки з анальгетичними властивостями та антимікробною дією проти грампозитивних штамів.Експериментальна частина. Два нових 2-аміно-2’-оксоспіро[4H-пірано[3,2-с][1,2]бензоксатіїн-4,3’-індолін]-3-карбонітрил 5,5-діоксиди були синтезовані за допомогою трикомпонентної реакції на основі 1,2-бензоксатіїн-4(3Н)-он 2,2-діоксиду. Протизапальну активність вивчали на моделі карагенінового набряку, анальгетичну активність оцінювали на моделі місцевої запальної гіпералгезії. Були проведені дослідження антимікробної активності отриманих сполук методом дифузії в агар.Висновки. Синтезовано нові спіро[бензо[е]пірано[3,2-с][1,2]оксатіїн-4,3’-індол]-3-карбонітрил 5,5-діоксиди. Отримані сполуки виявили високий рівень анальгетичної та антимікробної активності. Остання перевищує активність референс-препаратів і виявилася більш ефективною проти грампозитивних бактерій
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De novo assembly of the cattle reference genome with single-molecule sequencing.
BackgroundMajor advances in selection progress for cattle have been made following the introduction of genomic tools over the past 10-12 years. These tools depend upon the Bos taurus reference genome (UMD3.1.1), which was created using now-outdated technologies and is hindered by a variety of deficiencies and inaccuracies.ResultsWe present the new reference genome for cattle, ARS-UCD1.2, based on the same animal as the original to facilitate transfer and interpretation of results obtained from the earlier version, but applying a combination of modern technologies in a de novo assembly to increase continuity, accuracy, and completeness. The assembly includes 2.7 Gb and is >250× more continuous than the original assembly, with contig N50 >25 Mb and L50 of 32. We also greatly expanded supporting RNA-based data for annotation that identifies 30,396 total genes (21,039 protein coding). The new reference assembly is accessible in annotated form for public use.ConclusionsWe demonstrate that improved continuity of assembled sequence warrants the adoption of ARS-UCD1.2 as the new cattle reference genome and that increased assembly accuracy will benefit future research on this species
Triggers for displaced decays of long-lived neutral particles in the ATLAS detector
A set of three dedicated triggers designed to detect long-lived neutral particles decaying throughout the ATLAS detector to a pair of hadronic jets is described. The efficiencies of the triggers for selecting displaced decays as a function of the decay position are presented for simulated events. The effect of pile-up interactions on the trigger efficiencies and the dependence of the trigger rate on instantaneous luminosity during the 2012 data-taking period at the LHC are discussedFil: Aad, G.. Albert Ludwigs Universität; AlemaniaFil: Abajyan, T.. Universitaet Bonn; AlemaniaFil: Abbott, B.. University of Oklahoma; Estados UnidosFil: Abdallah, J.. Universitat Autònoma de Barcelona; EspañaFil: Abdel Khalek, S.. Universite Paris Sud; FranciaFil: Alconada Verzini, María Josefina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: Alonso, Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: Anduaga, Xabier Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: Dova, Maria Teresa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: González Silva, María Laura. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Monticelli, Fernando Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: Otero y Garzon, Gustavo Javier. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Piegaia, Ricardo Nestor. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Romeo, Gaston Leonardo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Tripiana, Martin Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: Zhuang, X.. Ludwig Maximilians Universitat; AlemaniaFil: Zhuravlov, V.. Max-Planck Institut für Physik; AlemaniaFil: Zieminska, D.. Indiana University; Estados UnidosFil: Zimin, N. I.. Joint Institute for Nuclear Research; RusiaFil: Zimmermann, R.. Universitaet Bonn; AlemaniaFil: Zimmermann, S.. Universitaet Bonn; AlemaniaFil: Zimmermann, S.. Albert Ludwigs Universität; AlemaniaFil: Ziolkowski, M.. Universität Siegen; AlemaniaFil: Zitoun, R.. Université de Savoie; FranciaFil: Živković, L.. Columbia University; Estados UnidosFil: Zmouchko, V. V.. State Research Center Institute for High Energy Physics; RusiaFil: Zobernig, G.. University of Wisconsin; Estados UnidosFil: Zoccoli, A.. Università di Bologna; ItaliaFil: zur Nedden, M.. Humboldt University; AlemaniaFil: Zutshi, V.. Northern Illinois University; Estados Unido
Modelling of large-scale structures arising under developed turbulent convection in a horizontal fluid layer (with application to the problem of tropical cyclone origination)
International audienceThe work is concerned with the results of theoretical and laboratory modelling the processes of the large-scale structure generation under turbulent convection in the rotating-plane horizontal layer of an incompressible fluid with unstable stratification. The theoretical model describes three alternative ways of creating unstable stratification: a layer heating from below, a volumetric heating of a fluid with internal heat sources and combination of both factors. The analysis of the model equations show that under conditions of high intensity of the small-scale convection and low level of heat loss through the horizontal layer boundaries a long wave instability may arise. The condition for the existence of an instability and criterion identifying the threshold of its initiation have been determined. The principle of action of the discovered instability mechanism has been described. Theoretical predictions have been verified by a series of experiments on a laboratory model. The horizontal dimensions of the experimentally-obtained long-lived vortices are 4÷6 times larger than the thickness of the fluid layer. This work presents a description of the laboratory setup and experimental procedure. From the geophysical viewpoint the examined mechanism of the long wave instability is supposed to be adequate to allow a description of the initial step in the evolution of such large-scale vortices as tropical cyclones - a transition form the small-scale cumulus clouds to the state of the atmosphere involving cloud clusters (the stage of initial tropical perturbation)
A whole-genome assembly of the domestic cow, Bos taurus
Background: The genome of the domestic cow, Bos taurus, was sequenced using a mixture of hierarchical and whole-genome shotgun sequencing methods. Results: We have assembled the 35 million sequence reads and applied a variety of assembly improvement techniques, creating an assembly of 2.86 billion base pairs that has multiple improvements over previous assemblies: it is more complete, covering more of the genome; thousands of gaps have been closed; many erroneous inversions, deletions, and translocations have been corrected; and thousands of single-nucleotide errors have been corrected. Our evaluation using independent metrics demonstrates that the resulting assembly is substantially more accurate and complete than alternative versions. Conclusions: By using independent mapping data and conserved synteny between the cow and human genomes, we were able to construct an assembly with excellent large-scale contiguity in which a large majority (approximately 91%) of the genome has been placed onto the 30 B. taurus chromosomes. We constructed a new cow-human synteny map that expands upon previous maps. We also identified for the first time a portion of the B. taurus Y chromosome. © 2009 Zimin et al.; licensee BioMed Central Ltd
Determination of the b quark mass at the M_Z scale with the DELPHI detector at LEP
An experimental study of the normalized three-jet rate of b quark events with
respect to light quarks events (light= \ell \equiv u,d,s) has been performed
using the CAMBRIDGE and DURHAM jet algorithms. The data used were collected by
the DELPHI experiment at LEP on the Z peak from 1994 to 2000. The results are
found to agree with theoretical predictions treating mass corrections at
next-to-leading order. Measurements of the b quark mass have also been
performed for both the b pole mass: M_b and the b running mass: m_b(M_Z). Data
are found to be better described when using the running mass. The measurement
yields: m_b(M_Z) = 2.85 +/- 0.18 (stat) +/- 0.13 (exp) +/- 0.19 (had) +/- 0.12
(theo) GeV/c^2 for the CAMBRIDGE algorithm. This result is the most precise
measurement of the b mass derived from a high energy process. When compared to
other b mass determinations by experiments at lower energy scales, this value
agrees with the prediction of Quantum Chromodynamics for the energy evolution
of the running mass. The mass measurement is equivalent to a test of the
flavour independence of the strong coupling constant with an accuracy of 7
permil.Comment: 24 pages, 10 figures, Accepted by Eur. Phys. J.
Study of Leading Hadrons in Gluon and Quark Fragmentation
The study of quark jets in e+e- reactions at LEP has demonstrated that the
hadronisation process is reproduced well by the Lund string model. However, our
understanding of gluon fragmentation is less complete. In this study enriched
quark and gluon jet samples of different purities are selected in three-jet
events from hadronic decays of the Z collected by the DELPHI experiment in the
LEP runs during 1994 and 1995. The leading systems of the two kinds of jets are
defined by requiring a rapidity gap and their sum of charges is studied. An
excess of leading systems with total charge zero is found for gluon jets in all
cases, when compared to Monte Carlo Simulations with JETSET (with and without
Bose-Einstein correlations included) and ARIADNE. The corresponding leading
systems of quark jets do not exhibit such an excess. The influence of the gap
size and of the gluon purity on the effect is studied and a concentration of
the excess of neutral leading systems at low invariant masses (<~ 2 GeV/c^2) is
observed, indicating that gluon jets might have an additional hitherto
undetected fragmentation mode via a two-gluon system. This could be an
indication of a possible production of gluonic states as predicted by QCD.Comment: 19 pages, 6 figures, Accepted by Phys. Lett.
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