8,839 research outputs found
Efeitos da administração sistêmica de 5-HT e 8-OH-DPAT sobre os estados de vigília e sono de pombos (Columba livia)
No full textDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas. Programa de Pós-Graduação em NeurociênciasInvestigar a participação dos mecanismos serotonérgicos sobre a regulação dos estados de sono e vigília em pombos por meio da caracterização comportamental e eletrográfica hipocampal dos estados de sono e vigília após administração sistêmica de 5-HT ou 8-OH-DPAT e quantificação dos efeitos da administração de 5-HT ou 8-OH-DPAT sobre a atividade eletrográfica hipocampal dos diferentes estados identificados
Towards robust complexity indices in linguistic typology
No full textAbstract
There is high hope that corpus-based approaches to language complexity will contribute to explaining linguistic diversity. Several complexity indices have consequently been proposed to compare different aspects among languages, especially in phonology and morphology. However, their robustness against changes in corpus size and content hasn’t been systematically assessed, thus impeding comparability between studies. Here, we systematically test the robustness of four complexity indices estimated from raw texts and either routinely utilized in crosslinguistic studies (Type-Token Ratio and word-level Entropy) or more recently proposed (Word Information Density and Lexical Diversity). Our results on 47 languages strongly suggest that traditional indices are more prone to fluctuation than the newer ones. Additionally, we confirm with Word Information Density the existence of a cross-linguistic trade-off between word-internal and across-word distributions of information. Finally, we implement a proof of concept suggesting that modern deep-learning language models can improve the comparability across languages with non-parallel datasets.</jats:p
Reactivity of 1,3- And 1,4-cyclohexadiene with OH radicals
No full textCyclohexadienes (CHD) are important intermediates in the pyrolysis and oxidation of many C6 cyclic hydrocarbons. These dienes either eliminate H2 directly or lose H-atom sequentially to produce the first aromatic ring “benzene”. This is the major reaction pathway for the formation of the first aromatic ring during pyrolysis and oxidation of C6 cyclic hydrocarbons. Despite its importance in the soot formation process, the chemistry of CHD has attracted less attention from the scientific community. In this work, we investigated the hydrogen abstraction reactions of 1,3- and 1,4-CHD by OH radicals using a shock tube and laser diagnostic techniques over the temperature range of 900 - 1300 K and pressures of ~ 1 and 4 atm. The reaction kinetics were followed by monitoring OH radicals near 307 nm. The measured rate coefficients for both CHD isomers with OH radicals can be represented by the following Arrhenius expressions in units of cm3 molecule-1 s-1: "(1,3 ? CHD + OH) = 9.03 × 101"" exp 5?1360 789:(1,4 ? CHD + OH) = 1.21 × 101"= exp 5?1475 789.Research reported in this publication was funded by the Office of Sponsored Research at King Abdullah University of Science and Technology (KAUST)
Laboratory study of Ca(OH)2 dissolution dynamics in artificial seawater
No full textLAUREA MAGISTRALEQuesta tesi riguarda la dissoluzione dell'idrossido di calcio - Ca(OH)2, chiamato anche slaked lime, SL - in acqua di mare artificiale. La ricerca si pone come intento la caratterizzazione della cinetica di dissoluzione, al fine di fornire informazioni per l'utilizzo di SL per l'alcalinizzazione degli oceani, poiché i suoi effetti dopo il rilascio in mare non sono stati ancora studiati in maniera esaustiva. L'utilizzo di SL per l'alcalinizzazione degli oceani ha due obiettivi principali: il contrasto dell'acidificazione degli oceani e l'assorbimento di CO2 mediante il sequestro dall'atmosfera. Una conoscenza approfondita della cinetica di dissoluzione è importante per ottimizzare la dispersione di SL, minimizzando al tempo stesso le possibili conseguenze negative per l’ecosistema marino.
La dissoluzione di SL è stata studiata tramite esperimenti di laboratorio monitorando alcune variabili dell’acqua di mare artificiale, con quantità variabili di Ca(OH)2. Le soluzioni, contenute in becher sotto agitazione, possiedono quindi un volume finito e costante e si trovano a contatto con l’atmosfera. Diversi parametri sono stati variati per misurare, mediante opportuni sensori, la risposta delle variabili, quali ad esempio: il pH e la conduttività, con risoluzione temporale di un secondo. Inoltre, sono state eseguite ulteriori misure per quantificare l’alcalinità e i residui solidi dopo la filtrazione delle soluzioni. I parametri variati durante le prove sono stati invece: la temperatura, la salinità, la tipologia di agitazione, la concentrazione e la modalità di dispersione dell’idrossido di calcio.
I risultati hanno evidenziato che il rilascio di SL in acqua di mare ha causato un aumento dei valori di pH, conducibilità e alcalinità. Il pH ha raggiunto valori tra 10 e 11 per concentrazioni di SL fino a 4 g/L. Oltre questa concentrazione è cresciuto rapidamente raggiungendo valori superiori a 12, come nel caso di 8 g/L. La variazione di conducibilità ha mostrato lo stesso comportamento del pH, con un forte aumento sopra la concentrazione di 4 g/L. L'alcalinità è aumentata in maniera significativa, in funzione della concentrazione di SL disciolto e del tempo intercorso dal suo rilascio. Tramite un’analisi di diffrazione ai raggi X, è stato rilevato che la materia filtrata è composta principalmente da brucite (Mg(OH)2) e calcite (CaCO3), lo SL viene invece completamente disciolto in soluzione. I dati presentati potranno essere utilizzati per testare e validare modelli di cinetica e fluidodinamica.This thesis concerns the dissolution kinetics of calcium hydroxide - Ca(OH)2, also known as slaked lime, SL - in artificial seawater. The aim of the research is to characterize the dissolution kinetics in order to provide information for the use of SL for ocean alkalinization, since the effects after its release into the sea have not yet been exhaustively studied. The use of SL for ocean alkalinization has two objectives: the contrast of ocean acidification and the CO2 absorption by sequestration from the atmosphere. An in-depth knowledge of the dissolution kinetics is important so as to optimize the dispersion of SL, minimizing at the same time the possible negative effects on the marine environment.
The SL dissolution was studied in laboratory experiments by monitoring some variables of artificial seawater, with varying amounts of added Ca(OH)2. The solutions, contained in beakers under stirring, with a finite and constant volume, are in contact with the atmosphere. Several parameters were varied to measure, using appropriate sensors, the response of the variables, such as: pH and conductivity, with temporal resolution of one second. Moreover, additional measurements were made to quantify the alkalinity and solid residues after filtration of the solutions. The parameters varied during the tests were instead: temperature, salinity, stirring mode, the concentration and mode of dispersion of calcium hydroxide.
The results show that the release of SL into seawater causes an increment in the values of pH, conductivity and alkalinity. The pH reaches values between 10 and 11, for SL concentrations up to 4 g/L. Above this concentration it grows rapidly, reaching values above 12, as in the case of 8 g/L. The variation of conductivity presents the same behaviour of the pH, with a sharp increase above the concentration of 4 g/L. Alkalinity increases significantly too, depending on the concentration and the time after the release of SL. The analysis of the filtered matter by X-ray diffraction reveals that it is mainly composed of brucite (Mg(OH)2) and calcite (CaCO3), while the SL is completely dissolved. The present data may be used to test and validate kinetics and fluid-dynamics models
Comparison of the stress between rapid thermal annealed and excimer laser annealed polycrystalline silicon thin films
No full textCharacteristics of polycrystalline silicon films with large substrate such as 50 mm x 50 mm, crystallized by using furnace annealing (FA), multi-step rapid thermal annealing (MSRTA) and excimer laser annealing (ELA) methods, have been investigated. In order to characterize the residual stress in crystalline silicon on coming 7059 glass, polarized Raman spectroscopy were measured for those various annealing methods and at various substrate temperatures. We observed that the polycrystalline Si films, crystallized by ELA, have a high crystalline volume fraction, residual stress and equiaxial crystal growth. On the other hand, silicon films crystallized by FA and MSRTA have a low compressive stress and dendritic structure, which are due to thermal relaxation. These Si films have a broad hump around 480 cm(-1) which indicates the existence of amorphous phase silicon. The magnitudes of stresses of FA and MSRTA are 4.07 x 10(9) and 4.46 x 10(9) dyne cm(-2), respectively and the magnitude stress of laser annealing decreases from 1.35 x 10(10) to 8.58 x 10(9) dyne cm(-2) with increasing the substrate temperature from room temperature to 400 degrees C. (C) 1998 Elsevier Science Ltd
CR1 Knops blood group alleles are not associated with severe malaria in the Gambia
No full textThe Knops blood group antigen erythrocyte polymorphisms have been associated with reduced falciparum malaria-based in vitro rosette formation (putative malaria virulence factor). Having previously identified single-nucleotide polymorphisms (SNPs) in the human complement receptor 1 (CR1/CD35) gene underlying the Knops antithetical antigens Sl1/Sl2 and McC(a)/McC(b), we have now performed genotype comparisons to test associations between these two molecular variants and severe malaria in West African children living in the Gambia. While SNPs associated with Sl:2 and McC(b+) were equally distributed among malaria-infected children with severe malaria and control children not infected with malaria parasites, high allele frequencies for Sl 2 (0.800, 1,365/1,706) and McC(b) (0.385, 658/1706) were observed. Further, when compared to the Sl 1/McC(a) allele observed in all populations, the African Sl 2/McC(b) allele appears to have evolved as a result of positive selection (modified Nei-Gojobori test Ka-Ks/s.e.=1.77, P-valu
SMA observations of the W3(OH) complex: Dynamical differentiation between W3(H2O) and W3(OH)
No full textWe present Submillimeter Array observations of the HCN (3-2) and HCO+ (3-2) molecular lines towards the W3(H2O) and W3(OH) star-forming complexes. Infall and outflow motions in the W3(H2O) have been characterized by observing HCN and HCO+ transitions. Highvelocity blue/red-shifted emission, tracing the outflow, show multiple knots, which might originate in episodic and precessing outflows. 'Blue-peaked' line profiles indicate that gas is infalling on to the W3(H2O) dust core. The measured large mass accretion rate, 2.3 x 10(-3) M-circle dot yr(-1), together with the small free-fall time-scale, 5 x 10(3) yr, suggest W3(H2O) is in an early evolutionary stage of the process of formation of high-mass stars. For the W3(OH), a two-layer model fit to the HCN and HCO+ spectral lines and Spizter/Infrared Array Camera (IRAC) images support that the W3(OH) H II region is expanding and interacting with the ambient gas, with the shocked neutral gas being expanding with an expansion time-scale of 6.4 x 10(3) yr. The observations suggest different kinematical time-scales and dynamical states for the W3(H2O) and W3(OH).National Natural Science Foundation of China [11373026, 11373009, 11433004, 11433008, U1331116]; National Basic Research Program of China (973 Program) [2012CB821800]; Top Talents Program of Yunnan Province [2015HA030]; Midwest universities comprehensive strength promotion project (Yunnan university) [XT412001]; Deutsche Forschungsgemeinschaft, DFG [SFB956]SCI(E)[email protected]
Quantum and its irreducible representations
No full textWe define for real a unital -algebra
quantizing the universal enveloping
-algebra of . The -algebra
is realized as a -subalgebra of the
Drinfeld double of and its dual Hopf -algebra
, generated by the equatorial Podle\'s sphere coideal
-subalgebra of and
its associated orthogonal coideal -subalgebra . We then classify all the irreducible
-representations of .Comment: 22 pages; author accepted manuscrip
On the sheaf-theoretic SL(2, C) Casson–Lin invariant
No full textWe prove that the (τ-weighted, sheaf-theoretic) SL(2, C) Casson–Lin invariant introduced by Manolescu and the first author is generically independent of the parameter τ and additive under connected sums of knots in integral homology 3-spheres. This addresses two questions asked by Manolescu and the first author. Our arguments involve a mix of topology and algebraic geometry, and rely crucially on the fact that the SL(2, C) Casson–Lin invariant admits an alternative interpretation via the theory of Behrend functions.</p
Candidatus Rhetoricae (or Novus Candidatus).
No full textThis little book is a find whatever it finally turns out to be! For now it seems to be a Jesuit collegium text in rhetoric following the Progymnasmata of Aphthonius. If one works from the back of the book, there is an apparently independent 48-page work, Angelus Pacis by Nicolas Caussini (Latinized name), S.J. The rest of the book seems to be a commentary on or presentation of Aphthonius' Progymnasmata in 3 parts covering 435 pages, followed by a T of C and an AI, which is often one page off. Pars II is titled Rhetoricae Praecepta, Pars III De Panegyrico seu Laudatione. Pars I seems to be Apparatus ad Fabulam et Narrationem. Fable is handled on 15-31. After the famous Greek definition of Theion done into Latin ( sermo falsus veritatem effingens ), the author distinguishes rational (human) and moral (animal) fables, with mixed fables including both. He holds (19) that the sense of the fable generally needs to be expressed; otherwise people often miss the point of a fable. His Latin for promythium is praefabulatio, for epimythium affabulatio. Apologus and parabola are identical for him with fabula. After describing the qualities and uses of fables, the author presents some nine fables that exemplify various levels of style, twice telling the same stories on two levels (WL and FC). The last example is of the florid style: The Silkworm and the Spider takes four pages to tell! I found this book sitting in a box of disparate, unmarked, old books. It pays to look!This is a hardbound book (hard cover)Language note: Bilingual: Greek/LatinElzevers
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