1,689 research outputs found

    FRV Scotia Cruise 1010S PROGRAMME

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    FRV Scotia Cruise 1010S PROGRAMME

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    FRV Scotia Cruise 1010S PROGRAMME

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    U ovom radu opisuje se lokalni političko – upravni sustavi u Hrvatskoj, Sloveniji i Italiji. Opisuje se kako su se mijenjali izborni sustavi u Republici Hrvatskoj od donošenja Ustava pa sve do danas. Navedeni su ovlasti i način prestanka mandata izvršnim čelnicima, te se uspoređuju načini i razlozi za raspuštanje lokalnih predstavničkih tijela. Također, vidjet ćemo na koje načine središnja vlast utječe na lokalnu samoupravu Hrvatske, Slovenije Italije te koji su način financiranja. U dijelu o Hrvatskim lokalno političkim sustavima obraća se pažnja na zadnje promjene Zakona o lokalnoj i područnoj (regionalnoj) samoupravi iz prosinca 2017. godine. U svakoj državi pojedinačno navedeno je koji su to upravni organi te kakve su njihove zadaće i funkcije. Cilj ovog rada je prikazati razlike i sličnosti u tri različita sustava lokalne samouprave, jednostupanjskom koji je u Sloveniji (općine/gradske općine), dvostupanjskom koji je u Hrvatskoj (općije/gradovi i županije) te trostupanjski u Italiji (općine, provincije i regije)

    Planetesimal Compositions in Exoplanet Systems

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    We have used recent surveys of the composition of exoplanet host stars to investigate the expected composition of condensed material in planetesimals formed beyond the snow line in the circumstellar nebulae of these systems. Of the major solid forming elements, we find that, as for the Sun, the C and O abundances (and particularly the C/O abundance ratio) have the most significant effect on the composition of icy planetesimals formed in these systems. The calculations use a self-consistent model for the condensation sequence of volatile ices from the nebula gas after refractory (silicate and metal) phases have condensed. The resultant proportions of refractory phases and ices were calculated for a range of nebular temperature structure and redox conditions. Planetesimals in systems with sub-solar C/O should be water ice-rich, with lower than solar mass fractions of refractory materials, while in super-solar C/O systems planetesimals should have significantly higher fractions of refractories, in some cases having little or no water ice. C-bearing volatile ices and clathrates also become increasingly important with increasing C/O depending on the assumed nebular temperatures. These compositional variations in early condensates in the outer portions of the nebula will be significant for the equivalent of the Kuiper Belt in these systems, icy satellites of giant planets and the enrichment (over stellar values) of volatiles and heavy elements in giant planet atmospheres.Comment: Accepted for publication in The Astrophysical Journa

    Bootstrap Confidence Regions for Optimal Operating Conditions in Response Surface Methodology

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    This article concerns the application of bootstrap methodology to construct a likelihood-based confidence region for operating conditions associated with the maximum of a response surface constrained to a specified region. Unlike classical methods based on the stationary point, proper interpretation of this confidence region does not depend on unknown model parameters. In addition, the methodology does not require the assumption of normally distributed errors. The approach is demonstrated for concave-down and saddle system cases in two dimensions. Simulation studies were performed to assess the coverage probability of these regions. AMS 2000 subj Classification: 62F25, 62F40, 62F30, 62J05. Key words: Stationary point; Kernel density estimator; Boundary kernel

    Dust Stratification in Young Circumstellar Disks

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    We present high-resolution infrared spectra of four YSOs (T Tau N, T Tau S, RNO 91, and HL Tau). The spectra exhibit narrow absorption lines of 12CO, 13CO, and C18O as well as broad emission lines of gas phase12CO. The narrow absorption lines of CO are shown to originate from the colder circumstellar gas. We find that the line of sight gas column densities resulting from the CO absorption lines are much higher than expected for the measured extinction for each source and suggest the gas to dust ratio is measuring the dust settling and/or grain coagulation in these extended disks. We provide a model of turbulence, dust settling and grain growth to explain the results. The techniques presented here allow us to provide some observationally-motivated bounds on accretion disk alpha in protostellar systems

    Frequencies of Lipopolysaccharide Core Types among Clinical Isolates of Escherichia coli Defined with Monoclonal Antibodies

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    Mouse monoclonal antibodies (MAbs) specific for the lipopolysaccharide (LPS) core types R1, R2, and R3 of Escherichia coli and a cross-reactive MAb that binds to the LPS core of almost all E. coli were used in ELISA to determine the frequency of cores resembling R1, R2, and R3 in strains of E. coli isolated from clinical samples (blood and urine specimens) and from the feces of asymptomatic individuals. Of the 180 wild-type isolates, 123 were assigned to R1 core type, 14 to R2, and 18 to R3. Twenty-five wild-type E. coli isolates could not be assigned to a particular core type and may have either an R4 or K12 core or a previously unrecognized core type. R1 core type was associated with O types 1, 4, 6, 8, and 18 and with K1 or K5 capsules. R3 was associated with O15.O75 isolates could be of either R1 or R2 core typ

    Effects of CO2 on H2O band profiles and band strengths in mixed H2O:CO2 ices

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    H2O is the most abundant component of astrophysical ices. In most lines of sight it is not possible to fit both the H2O 3 um stretching, the 6 um bending and the 13 um libration band intensities with a single pure H2O spectrum. Recent Spitzer observations have revealed CO2 ice in high abundances and it has been suggested that CO2 mixed into H2O ice can affect relative strengths of the 3 um and 6 um bands. We used laboratory infrared transmission spectroscopy of H2O:CO2 ice mixtures to investigate the effects of CO2 on H2O ice spectral features at 15-135 K. We find that the H2O peak profiles and band strengths are significantly different in H2O:CO2 ice mixtures compared to pure H2O ice. In all H2O:CO2 mixtures, a strong free-OH stretching band appears around 2.73 um, which can be used to put an upper limit on the CO2 concentration in the H2O ice. The H2O bending mode profile also changes drastically with CO2 concentration; the broad pure H2O band gives way to two narrow bands as the CO2 concentration is increased. This makes it crucial to constrain the environment of H2O ice to enable correct assignments of other species contributing to the interstellar 6 um absorption band. The amount of CO2 present in the H2O ice of B5:IRS1 is estimated by simultaneously comparing the H2O stretching and bending regions and the CO2 bending mode to laboratory spectra of H2O, CO2, H2O:CO2 and HCOOH.Comment: 12 pages, 11 figures, accepted by A&

    Spike timing and synaptic plasticity in the premotor pathway of birdsong

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    The neural circuits of birdsong appear to utilize specific time delays in their operation. In particular, the anterior forebrain pathway (AFP) is implicated in an approximately 40- to 50- ms time delay, ΔT, playing a role in the relative timing of premotor signals from the nucleus HVc to the nucleus robust nucleus of the archistratium (RA) and control/learning signals from the nucleus lateral magnocellular nucleus of the anterior neostratium (lMAN) to RA. Using a biophysical model of synaptic plasticity based on experiments on mammalian hippocampal and neocortical pyramidal neurons, we propose an understanding of this ≈ 40- to 50- ms delay. The biophysical model describes the influence of Ca2+ influx into the postsynaptic RA cells through NMDA and AMPA receptors and the induction of LTP and LTD through complex metabolic pathways. The delay, ΔT, between HVc → RA premotor signals and lMAN → RA control/learning signals plays an essential role in determining if synaptic plasticity is induced by signaling from each pathway into RA. If ΔT is substantially larger than 40 ms, no plasticity is induced. If ΔT is much less than 40 ms, only potentiation is expected. If ΔT≈ 40 ms, the sign of synaptic plasticity is sensitive to ΔT. Our results suggest that changes in ΔT may influence learning and maintenance of birdsong. We investigate the robustness of this result to noise and to the removal of the Ca2+ contribution from lMAN → RA NMDA receptors. © Springer-Verlag 2004.Fil: Abarbanel, Henry D. I.. University of California at San Diego; Estados UnidosFil: Gibb, Leif. University of California at San Diego; Estados UnidosFil: Mindlin, Bernardo Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Rabinovich, M.I.. University of California at San Diego; Estados UnidosFil: Talathi, Sachin. University of California at San Diego; Estados Unido
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