We developed an ultra-stable and accurately-controllable Michelson interferometer to be used in a deeply unbalanced arm configuration for split-pulse XUV Ramsey-type spectroscopy with high-order ...laser harmonics. The implemented active and passive stabilization systems allow one to reach instabilities in the nanometer range over meters of relative optical path differences. Producing precisely delayed pairs of pump pulses will generate XUV harmonic pulses that may significantly improve the achievable spectral resolution and the precision of absolute frequency measurements in the XUV.
Leukocyte migration from blood into lymphoid and non-lymphoid tissues requires a highly orchestrated series of adhesive and signaling events. A network of adhesion molecules with overlapping ...functions mediate the capture, rolling and firm adhesion of leukocytes to the vascular endothelium. A new study adds a novel twist to this paradigm by demonstrating that two adhesion molecules, CD44 and VLA-4, must be physically associated with each other on activated T cells to mediate efficient rolling and firm adhesion.
In the frame of the IP-EUROTRANS (6th Framework Program EU), domain DEMETRA, ENEA was involved in the Work Package 4.5 “
Large Scale Integral Test”, devoted to characterize a relevant portion of a ...sub-critical ADS reactor block (core, internals, heat exchanger, cladding for fuel elements) in steady state, transient and accidental conditions. More in details ENEA assumed the commitment to perform an integral experiment aiming to reproduce the primary flow path of the “
European Transmutation Demonstrator (ETD)” pool-type nuclear reactor, cooled by Lead Bismuth Eutectics (LBE).
This experimental activity, called “
Integral Circulation Experiment (ICE)”, has been implemented merging the efforts of several research institutes, among which, besides ENEA, FZK, CRS4 and University of Pisa, allowing to design an appropriate test section to be installed in the CIRCE facility. The goal of the experiments is therefore to demonstrate the technological feasibility of a heavy liquid metal (HLM) nuclear system pool-type in a relevant scale (1
MW), investigating the related thermal–hydraulic behaviour (heat source and heat exchanger coupling, primary system and downcomer coupling, gas trapping into the main stream, thermal stratification in the pool, forced and mixed convection in rod bundle) under both steady state and transient conditions.
Moreover the preliminary as well as the planned experiments aims to address performance and reliability tests of some prototypical components, such as heat source, heat exchanger, chemistry control system.
The paper reports a detailed description of the experiment, the design performed for the test section and its main components as well as the preliminary experimental results carried out in the first experimental campaign run on the CIRCE pool, which consists of a full power steady state test.
The preliminary experimental results carried out have demonstrate the proper design of the test section trough the experiment goals as well as the HLM primary system technological viability. Moreover the results depicted into the paper are the first experimental data made available, especially for what concern the HLM pool thermal–hydraulic in a large scale system.
We study the integrable model with minimally and non-minimally coupled scalar fields and the correspondence of their general solutions. Using the model with a minimally coupled scalar field and a the ...constant potential as an example we demonstrate the difference between the general solutions of the corresponding models in the Jordan and the Einstein frames.
Three different scenarios of switchgrass (
Panicum virgatum L.) cultivation (high, mild and low) in two different environmental conditions (North and South Italy) were economically analysed by the ...computerized model BEE. The dataset was mostly generated from an 8.6
ha field of switchgrass planted in 2002 at the University of Bologna (North Italy). Annual equivalent costs (AEC) and break-even yield (BEY, i.e. the dry matter yield at which cost equals selling price) of each scenario were calculated to assess the feasibility of each scenario. AEC ranged from €511 to €1.257
ha
−1 being always higher in northern than southern regions. As expected, BEY varied to an extent depending on input levels. BEY was clearly higher under intensive cropping systems (
H
S) compared to mild-(
M
S) and low-input (
L
S) scenarios. However, even for
M
S or
L
S, BEY generally exceeded the harvested yield. Therefore, we can conclude that, at the market price of €55
Mg
−1 (dry basis), switchgrass can be hardly grown both in North and South Italy. However, the biomass market price appeared surprisingly underestimated if compared to the unit energy price of crude oil, therefore a desirable increase of biomass price could be expected in the next few years. Sensitivity analysis showed that biomass price strongly affects BEY, and this was especially found in
H
S. Furthermore, the differences in BEY between
L
S and
H
S clearly decreased with increasing market prices. Therefore,
H
S could be better indicated than
L
S at high market prices. Switchgrass was found to be more profitable than some conventional crops to an extent depending on the yield higher than BEY (
Y
i
). At the current biomass price,
Y
i
was from less than 1
Mg
ha
−1 (maize and alfalfa) to more than 4
Mg
ha
−1 (sugarbeet).
Context.
Outflows accelerated by active galactic nuclei (AGN) are commonly observed in the form of coherent, mildly collimated high-velocity gas directed along the AGN ionisation cones and ...kinetically powerful (≳10
44 − 45
erg s
−1
) jets. Recent works found that outflows can also be accelerated by low-power (≲10
44
erg s
−1
) jets, and the most recent cosmological simulations indicate that these are the dominant source of feedback on sub-kiloparsec scales, but little is known about their effect on the galaxy host.
Aims.
We study the relation between radio jets and the distribution and kinematics of the ionised gas in
IC 5063
,
NGC 5643
,
NGC 1068,
and
NGC 1386
as part of our survey of nearby Seyfert galaxies called Measuring Active Galactic Nuclei Under MUSE Microscope (MAGNUM). All these objects host a small-scale (≲1 kpc) low-power (≲10
44
erg s
−1
) radio jet that has small inclinations (≲45°) with respect to the galaxy disc.
Methods.
We employed seeing-limited optical integral field spectroscopic observations from the Multi Unit Spectroscopic Explorer (MUSE) at the Very Large Telescope to obtain flux, kinematic, and excitation maps of the extended ionised gas. We compared these maps with archival radio images and in one case, with
Chandra
X-ray observations.
Results.
We detect a strong (up to ≳800–1000 km s
−1
) and extended (≳1 kpc) emission-line velocity spread perpendicular to the direction of the AGN ionisation cones and jets in all four targets. The gas excitation in this region of line-width enhancement is entirely compatible with shock ionisation. These broad and symmetric line profiles are not associated with a single coherent velocity of the gas. A ‘classical’ outflow component with net blueshifted and redshifted motions is also present, but is directed along the ionisation cones and jets.
Conclusions.
We interpret the observed phenomenon as due to the action of the jets perturbing the gas in the galaxy disc. These intense and extended velocity spreads perpendicular to AGN jets and cones are indeed currently only observed in galaxies hosting a low-power jet whose inclination is sufficiently low with respect to the galaxy disc to impact on and strongly affect its material. In line with cosmological simulations, our results demonstrate that low-power jets are indeed capable of affecting the host galaxy.
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