231 research outputs found

    Влияние семантики локализованности на текстовую внешнетемпоральную транспозицию

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    Языковая временная семантика в лингвистических исследованиях последних лет рассматривается как широкая сфера языковых/речевых отношений различных категорий (грамматических, функционально- семантических, текстовых), т.е. как область пересечения, иногда концентрации аспектуального, собственно темпорального, таксисного и другого аналогичного содержания, где центральное место принадлежит глагольной единице, потенциальные функциональные возможности которой и определяют указанные грамматические отношения

    Quark Gluon Plasma an Color Glass Condensate at RHIC? The perspective from the BRAHMS experiment

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    We review the main results obtained by the BRAHMS collaboration on the properties of hot and dense hadronic and partonic matter produced in ultrarelativistic heavy ion collisions at RHIC. A particular focus of this paper is to discuss to what extent the results collected so far by BRAHMS, and by the other three experiments at RHIC, can be taken as evidence for the formation of a state of deconfined partonic matter, the so called quark-gluon-plasma (QGP). We also discuss evidence for a possible precursor state to the QGP, i.e. the proposed Color Glass Condensate.Comment: 32 pages, 18 figure

    Pseudorapidity distributions of charged particles from Au+Au collisions at the maximum RHIC energy, Sqrt(s_NN) = 200 GeV

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    We present charged particle densities as a function of pseudorapidity and collision centrality for the 197Au+197Au reaction at Sqrt{s_NN}=200 GeV. For the 5% most central events we obtain dN_ch/deta(eta=0) = 625 +/- 55 and N_ch(-4.7<= eta <= 4.7) = 4630+-370, i.e. 14% and 21% increases, respectively, relative to Sqrt{s_NN}=130 GeV collisions. Charged-particle production per pair of participant nucleons is found to increase from peripheral to central collisions around mid-rapidity. These results constrain current models of particle production at the highest RHIC energy.Comment: 4 pages, 5 figures; fixed fig. 5 caption; revised text and figures to show corrected calculation of and ; final version accepted for publicatio

    GA-NIFS: Black hole and host galaxy properties of two z\simeq6.8 quasars from the NIRSpec IFU

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    Integral Field Spectroscopy (IFS) with JWST NIRSpec will significantly improve our understanding of the first quasars, by providing spatially resolved, infrared spectroscopic capabilities which cover key rest-frame optical emission lines that have been previously unobservable. Here we present our results from the first two z>6 quasars observed as a part of the Galaxy Assembly with NIRSpec IFS (GA-NIFS) GTO program, DELS J0411-0907 at z=6.82 and VDES J0020-3653 at z=6.86. By observing the Hβ\beta, [OIII], and Hα\alpha emission lines in these high-z quasars for the first time, we measure accurate black hole masses, MBH=1.85e9M_{\rm{BH}}=1.85e9 and 2.9e92.9e9M_\odot, corresponding to Eddington ratios of λEdd=0.8\lambda_{\rm{Edd}}=0.8 and 0.4 for DELS J0411-0907 and VDES J0020-3653 respectively. These provide a key comparison for existing estimates from the more uncertain MgII line. We perform quasar-host decomposition using models of the quasars' broad lines to measure the underlying host galaxies. We also discover multiple emission line regions surrounding each of the host galaxies, which are likely companion galaxies undergoing mergers with these hosts. We measure the star formation rates, excitation mechanisms, and dynamical masses of the hosts and companions, measuring the MBH/MdynM_{\rm{BH}}/M_{\rm{dyn}} ratios at high-z using these estimators for the first time. DELS J0411-0907 and VDES J0020-3653 both lie above the local black hole--host mass relation, and are consistent with the existing observations of z6z\gtrsim6 quasar host galaxies with ALMA. We detect ionized outflows in [OIII] and Hβ\beta from both quasars, with mass outflow rates of 58 and 525 M_{\odot}/yr for DELS J0411-0907 and VDES J0020-3653, much larger than their host star formation rates of <33 and <54 M_\odot/yr. This work highlights the exceptional capabilities of the JWST NIRSpec IFU for observing quasars in the early Universe.Comment: 27 pages, 10 figures. Resubmitted to A&A after significant revisions. If you have cited values from our first version, please check this version and update accordingly, as many values have changed slightly thanks to improvements in our analysi

    A massive black hole in a low-metallicity AGN at z5.55z\sim5.55 revealed by JWST/NIRSpec IFS

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    We present JWST/NIRSpec Integral Field Spectrograph rest-frame optical data of the compact z=5.55z=5.55 galaxy GS_3073. Its prominent broad components in several hydrogen and helium lines (while absent in the forbidden lines), and the detection of a large equivalent width of He II λ4686\lambda4686, EW(He II) 20\sim20 Angstrom, unambiguously identify it as an active galactic nucleus (AGN). We measure a gas-phase metallicity of Zgas/Z0.210.04+0.08Z_{\rm gas}/Z_\odot\sim0.21^{+0.08}_{-0.04}, lower than what has been inferred for both more luminous AGN at similar redshift and lower redshift AGN. We empirically show that classical emission line ratio diagnostic diagrams cannot be used to distinguish between the primary ionisation source (AGN or star formation) for such low-metallicity systems, whereas different diagnostic diagrams involving He IIλ4686\lambda4686 prove very useful, independent of metallicity. We measure the central black hole mass to be log(MBH/M)8.200.16+0.11\log(M_{\rm BH}/M_\odot)\sim8.20^{+0.11}_{-0.16}. While this places GS_3073 at the lower end of known high-redshift black hole masses, it still appears to be over-massive compared to its host galaxy properties. We detect an outflow with projected velocity 700\gtrsim700~km/s and an ionised gas mass outflow rate of about 100 M/100\ M_\odot/yr, suggesting that GS_3073 is able to enrich the intergalactic medium with metals one billion years after the Big Bang.Comment: 15 pages, 10 figures; comments are welcome. Submitted to A&

    Effect of arbuscular mycorrhizal (AM) colonization on terpene emission and content of Artemisia annua L.

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    Plant roots interact with a wide variety of rhizospheric microorganisms, including bacteria and the symbiontic arbuscular mycorrhizal (AM) fungi. The mycorrhizal symbiosis represents a series of complex feedbacks between plant and fungus regulated by their physiology and nutrition. Despite the widespread distribution and ecological significance of AM symbiosis, little is known about the potential of AM fungi to affect plant VOC metabolism. The purpose of this study was to investigate whether colonization of plant roots by AM fungi and associated soil microorganisms affects VOC emission and content of Artemisia annua L. plants (Asteraceae). Two inoculum types were evaluated: one consisted of only an arbuscular mycorrhizal (AM) fungus species (Glomus spp.), and the other was a mixture of different Glomus species and associated soil bacteria. Inoculated plants were compared with non-inoculated plants and with plants supplemented with extra phosphorus (P) to obtain plants of the same size as mycorrhizal plants, thus excluding potentially-confounding mycorrhizal effects on shoot growth. VOC emissions of Artemisia annua plants were analyzed by leaf cuvette sampling followed by off-line measurements with pre-concentration and gas chromatography mass spectrometry (GC-MS). Measurements of CO2 and H2O exchanges were conducted simultaneously. Several volatile monoterpenes were identified and characterized from leaf emissions of Artemisia annua L. by GC-MS analysis. The main components identified belong to different monoterpene structures: alpha-pinene, beta-pinene, camphor, 1,8-cineole, limonene, and artemisia ketone. A good correlation between monoterpene leaf concentration and leaf emission was found. Leaf extracts included also several sesquiterpenes. Total terpene content and emission was not affected by AM inoculation with or without bacteria, while emission of limonene and artemisia ketone was stimulated by this treatment. No differences were found among treatments for single monoterpene content, while accumulation of specific sesquiterpenes in leaves was altered in mycorrhizal plants compared to control plants. Growth conditions seemed to have mainly contributed to the outcome of the symbiosis and influenced the magnitude of the plant response. These results highlight the importance of considering the below-ground interaction between plant and soil for estimating VOC emission rates and their ecological role at multitrophic level

    Speed of cooling after cardiac arrest in relation to the intervention effect: a sub-study from the TTM2-trial

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    Background: Targeted temperature management (TTM) is recommended following cardiac arrest; however, time to target temperature varies in clinical practice. We hypothesised the effects of a target temperature of 33 °C when compared to normothermia would differ based on average time to hypothermia and those patients achieving hypothermia fastest would have more favorable outcomes. Methods: In this post-hoc analysis of the TTM-2 trial, patients after out of hospital cardiac arrest were randomized to targeted hypothermia (33 °C), followed by controlled re-warming, or normothermia with early treatment of fever (body temperature, ≥ 37.8 °C). The average temperature at 4 h (240 min) after return of spontaneous circulation (ROSC) was calculated for participating sites. Primary outcome was death from any cause at 6 months. Secondary outcome was poor functional outcome at 6 months (score of 4-6 on modified Rankin scale). Results: A total of 1592 participants were evaluated for the primary outcome. We found no evidence of heterogeneity of intervention effect based on the average time to target temperature on mortality (p = 0.17). Of patients allocated to hypothermia at the fastest sites, 71 of 145 (49%) had died compared to 68 of 148 (46%) of the normothermia group (relative risk with hypothermia, 1.07; 95% confidence interval 0.84-1.36). Poor functional outcome was reported in 74/144 (51%) patients in the hypothermia group, and 75/147 (51%) patients in the normothermia group (relative risk with hypothermia 1.01 (95% CI 0.80-1.26). Conclusions: Using a hospital's average time to hypothermia did not significantly alter the effect of TTM of 33 °C compared to normothermia and early treatment of fever. Keywords: Hypothermia; Out of hospital cardiac arrest; Temperature management; Time to target temperature

    Co-Transport of Polycyclic Aromatic Hydrocarbons by Motile Microorganisms Leads to Enhanced Mass Transfer under Diffusive Conditions.

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    The environmental chemodynamics of hydrophobic organic chemicals (HOCs) are often rate-limited by diffusion in stagnant boundary layers. This study investigated whether motile microorganisms can act as microbial carriers that enhance mass transfer of HOCs through diffusive boundary layers. A new experimental system was developed that allows (1) generation of concentration gradients of HOCs under the microscope, (2) exposure and direct observation of microorganisms in such gradients, and (3) quantification of HOC mass transfer. Silicone O-rings were integrated into a Dunn chemotaxis chamber to serve as sink and source for polycyclic aromatic hydrocarbons (PAHs). This resulted in stable concentration gradients in water (>24 h). Adding the model organism <i>Tetrahymena pyriformis</i> to the experimental system enhanced PAH mass transfer up to hundred-fold (benzo­[a]­pyrene). Increasing mass transfer enhancement with hydrophobicity indicated PAH co-transport with the motile organisms. Fluorescence microscopy confirmed such transport. The effective diffusivity of <i>T. pyriformis</i>, determined by video imaging microscopy, was found to exceed molecular diffusivities of the PAHs up to four-fold. Cell-bound PAH fractions were determined to range from 28% (naphthalene) to 92% (pyrene). Motile microorganisms can therefore function as effective carriers for HOCs under diffusive conditions and might significantly enhance mobility and availability of HOCs

    Analysis of a sprint ski race and associated laboratory determinants of world-class performance

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    This investigation was designed to analyze the time-trial (STT) in an international cross-country skiing sprint skating competition for (1) overall STT performance and relative contributions of time spent in different sections of terrain, (2) work rate and kinematics on uphill terrain, and (3) relationships to physiological and kinematic parameters while treadmill roller ski skating. Total time and times in nine different sections of terrain by 12 world-class male sprint skiers were determined, along with work rate and kinematics for one specific uphill section. In addition, peak oxygen uptake (VO2peak), gross efficiency (GE), peak speed (Vpeak), and kinematics in skating were measured. Times on the last two uphill and two final flat sections were correlated to overall STT performance (r = ~−0.80, P < 0.001). For the selected uphill section, speed was correlated to cycle length (r = −0.75, P < 0.01) and the estimated work rate was approximately 160% of peak aerobic power. VO2peak, GE, Vpeak, and peak cycle length were all correlated to STT performance (r = ~−0.85, P < 0.001). More specifically, VO2peak and GE were correlated to the last two uphill and two final flat section times, whereas Vpeak and peak cycle length were correlated to times in all uphill, flat, and curved sections except for the initial section (r = ~−0.80, P < 0.01). Performances on uphill and flat terrain in the latter part were the most significant determinants of overall STT performance. Peak oxygen uptake, efficiency, peak speed, and peak cycle length were strongly correlated to overall STT performance, as well as to performance in different sections of the race
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