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The aim of the present research is to verify the immune status against tetanus in students and workers exposed to risk and to ascertain whether a decennial booster is necessary. Antibodies against tetanus were measured in 1433 workers and students of Padua University (Italy). The enrolment criterion was the ability to provide a booklet of vaccinations released by a public health office. The influence of age, gender, the number of vaccine doses, and the interval since the last dose was determined. Ten years after the last dose, the majority of subjects (95·0%) displayed an antibody titre above the protective level (⩾0·10 IU/ml), and half of these (49·1%) had a long-term protective level (⩾1·0 IU/ml). According to our data, titre depends on both the number of vaccine doses and the interval since the last dose (P < 0·0001). Five vaccine doses and an interval of at least 10 years since the last dose are predictive of a long-term protective titre in absence of a booster (1·97 IU/ml). These data suggest that when primary series are completed, a decennial booster is unnecessary for up to 20 years. Furthermore, we recommend measuring the antibody level before a new booster is given to prevent problems related to over-immunisation.
The study of the anisotropies of the submillimeter relict radiation (RR) can provide important arguments to select among different theoretical scenarios (Panek and Rudak 1988). However, interstellar dust (ISD) emission is present in this spectral region and its patchy distribution can heavily contaminate anisotropy measurements. For example, the most sensitive measurement of CBR anisotropies has been reported so far in a broad band around 1 mm (Melchiorri et al. 1981): the detection of anisotropy is statistically very significant, but its cosmological origin is questionable.
The motion of the earth with respect to the distant matter frame produces a spectral distortion in the observed background radiation given by
The second-order approximation in β gives (de Bernardis et al., 1989) 2 where α≅(dlnI/dln v) = (v/I)(dI/dv). The first term in cosθ of equation (2) is the usual dipole anisotropy, the second constant term is the equivalent of the transverse Doppler effect in special relativity, and the third term is the quadrupole anisotropy. It is interesting to note that the quadrupole term is zero in the Rayleigh-Jeans region of the blackbody spectrum: Q ≈ 1/2(3–α)(2–α)β2cos2θ.
Autism spectrum disorders (ASDs) are pervasive and multifactorial neurodevelopmental conditions, characterized by impairments in social communication and interaction, and restricted, repetitive patterns of behaviour, interests or activities. Treatment options to ameliorate symptoms of ASDs are limited. Heterogeneity complicates the quest for personalized medicine in this population. Our aim was to investigate if there are baseline characteristics of patients that moderate response or trial design features that impede the identification of efficacious interventions for ASDs.
Literature searches of EMBASE, MEDLINE and PsycINFO identified 43 studies for qualitative assessment of baseline characterization of participants and 37 studies for quantitative analysis of moderators of treatment response. Criteria included blinded randomized controlled trials (RCTs) in paediatric ASD, with at least 10 participants per arm or 20 overall, of oral treatments, including pharmacological interventions and dietary supplements.
Random-effects meta-analysis of 1997 participants (81% male) identified three moderators associated with an increase in treatment response: trials located in Europe and the Middle-East; outcome measures designated primary status; and the type of outcome measure. Inconsistent reporting of baseline symptom severity and intellectual functioning prevented analysis of these variables. Qualitative synthesis of baseline characteristics identified at least 31 variables, with only age and gender reported in all trials. Biological markers were included in six RCTs.
Few trials reported adequate baseline characteristics to permit detailed analysis of response to treatment. Consideration of geographical location, baseline severity and intellectual function is required to ensure generalizability of results. The use of biological markers and correlates in ASD trials remains in its infancy. There is great need to improve the application of baseline characterization and incorporation of biological markers and correlates to permit selection of participants into homogeneous subgroups and to inform response to treatment in ASD.
In the 1998-99 flight, BOOMERanG has produced maps of ∼4% of the sky at high Galactic latitudes, at frequencies of 90, 150, 240 and 410 GHz, with resolution ≳ 10'. The faint structure of the Cosmic Microwave Background at horizon and sub-horizon scales is evident in these maps. These maps compare well to the maps recently obtained at lower frequencies by the WMAP experiment. Here we compare the amplitude and morphology of the structures observed in the two sets of maps. We also outline the polarization sensitive version of BOOMERanG, which was flown early this year to measure the linear polarization of the microwave sky at 150, 240 and 350 GHz.
BOOMERanG has recently resolved structures on the last scattering surface at redshift ˜ 1100 with high signal to noise ratio. We review the technical advances which made this possible, and we focus on the current results for maps and power spectra, with special attention to the determination of the total mass-energy density in the Universe and of other cosmological parameters.
We show how estimates of parameters characterizing inflation-based theories of structure formation localized over the past year when large scale structure (LSS) information from galaxy and cluster surveys was combined with the rapidly developing cosmic microwave background (CMB) data, especially from the recent Boomerang and Maxima balloon experiments. All current CMB data plus a relatively weak prior probability on the Hubble constant, age and LSS points to little mean curvature (Ωtot = 1.08±0.06) and nearly scale invariant initial fluctuations (ns = 1.03±0.08), both predictions of (non-baroque) inflation theory. We emphasize the role that degeneracy among parameters in the Lpk = 212 ± 7 position of the (first acoustic) peak plays in defining the Ωtot range upon marginalization over other variables. Though the CDM density is in the expected range (Ωcdmh2 = 0.17 ± 0.02), the baryon density Ωbh2 = 0.030 ± 0.005 is somewhat above the independent 0.019 ± 0.002 nucleosynthesis estimates. CMB+LSS gives independent evidence for dark energy (ΩΛ = 0.66 ± 0.06) at the same level as from supernova (SN1) observations, with a phenomenological quintessence equation of state limited by SN1+CMB+LSS to wQ < −0.7 cf. the wQ=−1 cosmological constant case.
In this work, the epitaxial silicon deposition by SiHCl3-hydrogen mixtures in a AMT 7700 barrel reactor was analyzed through a detailed model where a three dimensional flow dynamic was solved by reduction to a two dimensional geometry under cylindrical coordinates. The model was used to investigate the role of the reactor geometry and of the process parameters on the axial deposition uniformity. A comparison with industrial experimental data was also performed.
The surface and gas-phase kinetic of deposition of diamond-like carbon films (DLC) obtained in plasma reactors using methane as precursor was here investigated. Kinetic constants of electronic reactions were evaluated using experimental ionization and neutral dissociation cross sections and the Druyvestein electron distribution function. Kinetic constants for ionic and neutral reactions were found in the literature. Surface reactions were divided into processes involving the impingement of gas-phase radicals or ions from the plasma and desorption or recombination reactions of adsorbed surface species. The kinetic constants of the former processes were evaluated.from the ambipolar theory or from the kinetic theory of gases, while the other kinetic constants were determined from analogy with hydrocarbon chemistry. The exception is the desorption of adsorbed methyl radicals, whose kinetic constant was fitted over experimental data. The predictivity of the model was tested through the simulation of three reactors described in the literature widely differing for operating conditions.
The Low Pressure Chemical Vapor Deposition of Si from SiH4 is an industrial process that can be used to deposit epitaxial Si at relatively low surface temperatures. Multiscale models are necessary in order to tune the operating conditions to optimize the quality of the deposited materials. In this work we present a multiscale approach meant to describe the film morphological evolution at different time and length scales. The reactor fluid dynamics and overall mass and temperature balances are solved with the finite element method. The morphological evolution of the film is investigated with 3D kinetic Monte Carlo. We have systematically investigated the dependence of the growth morphology from temperature, pressure and gas phase composition (SiH4/H2 ratio) with the aim of determining the operating parameters window that can lead to the best film morphology. We found that the presence of a significant amount of hydrogen on the surface can significantly influence the surface morphology. In particular hydrogen can be considered as the principal responsible of the transition from an order terrace step flow growth regime, which prevails at high temperatures, to a disordered 3 dimensional growth regime. It is also worth noting that our KMC simulations show that the hydrogen surface chemistry active at low temperatures is probably richer than expected, since the formation of a significant number of island on the surface dramatically increases the concentration of steps, and thus the variety of configurations by which two adsorbed H atoms can interact.
We summarize the results of the Cosmic Microwave Background (CMB)
working group of the ARENA project. The focus has been on
precision measurements of CMB polarization (looking for the echoes
of cosmological inflation) and high angular resolution CMB
measurements (looking for Sunyaev Zeldovich effect in distant
clusters of Galaxies, to probe the evolution of the Universe, Dark
Matter and Dark Energy). For both projects the Dome C site
represents the best choice worldwide.
Large millimetric and submillimetric telescopes can play a crucial
role in our understanding of the Universe, allowing the direct
measurement of early galaxies or the investigation of the earliest
stages of star formation. The B modes of CMB polarization are a
direct probe of the Inflationary epoch and their measurement
promises to provide information on the scale of energies at which
the process took place. For these investigations (and many
others), large detectors arrays with thousands of pixels are
needed, to achieve high mapping speeds. This is especially true in
the case of mm and sub/mm observations from extremely cold and dry
locations like Dome-C, where ultra-low temperature detectors,
reaching photon noise limited performance, are needed to fully
exploit the excellent quality of the site. In this paper we
present the working principle of the Microwave Kinetic Inductance
Detectors and their status of development in Italy, focusing on
the key aspects that make them ideal for large arrays of sensors.
Cosmic Microwave Background observations became the tool to probe the
the first events of cosmic history. After WMAP data releases,
galactic and extragalactic foregrounds are perceived as the main limiting uncertainity for the near-future search for the B-mode polarization inprints from
the inflationary era, either through satellites or ground-based experiments like Brain at Dome-C. A combination of technology, scanning strategy and above all, accurate knowledge of polarized foregrounds will be necessary for an optimal mapping of B-mode CMB Polarization. In addition, the search for a better understanding of the galactic foregrounds will provide unprecedented knowledge on the Milky Way structure and star formation.
Future cosmology space missions will concentrate on measuring the
polarization of the Cosmic Microwave Background (CMB), which potentially
carries invaluable information about the earliest phases of the evolution
of our universe. Such ambitious projects will ultimately be limited by
the sensitivity of the instrument and by the accuracy at which
polarized foreground emission from our own Galaxy can be subtracted
out. We present the PILOT balloon project which will aim at
characterizing one of these foreground sources, the polarization of
the dust continuum emission in the diffuse interstellar medium. The
PILOT experiment will also constitute a test-bed for using
multiplexed bolometer arrays for polarization measurements.
In the current cosmological scenario, part of the linearly polarized
emission of the CMB is expected to be rotational (B-modes). This
component is due to tensor perturbations of the metric produced by
primordial gravitational waves, which are generated a split-second after the
Big Bang. The signal expected is of the order of ≲ 0.1 μK, well below the non-rotational component of the polarization
signal (E-modes), and beyond the sensitivity of present generation
instruments. New, more sensitive instruments are developed in
several labs, with the goal to measure the B-modes. Control of
systematics and foregrounds will be the key to make the results of
these experiments believable. In this paper we shortly outline
BRAIN, a bolometric interferometer devoted to B-modes research,
and its pathfinder experiment, devoted to test the Dome-C site.
The BaR-SPOrt experiment is designed to measure the E-mode
power spectrum of the Cosmic Microwave Background Polarization (CMBP)
in the multipole range 50 < l < 1000.
In the current configuration at 32 GHz
it can explore up to l = 400.
Recent low frequency observations of the target region show that
the synchrotron emission should not contamine the CMBP already at 32 GHz.
A 6-month observation of a 6° × 6° sky area
during the polar night, in ideal
environmental conditions, will allow the Italian-French collaboration
to both measure the E–mode power spectrum with appropriate sensitivity
and perform important tests of the anomalous dust emission.
The BaR-SPOrt 32 GHz instrument, now under test and ready
for operations by Spring 2005, is proposed
for 1–2 years Winter operations at Dome C.
The BaR-SPOrt (Balloon-Borne Radiometers for Sky Polarization
Observations) experiment, a program of the Agenzia Spaziale
Italiana (ASI) co-funded by PNRA (Progetto Nazionale di Ricerca in
Antartide) was originally designed as a payload for long duration
balloons flights. The changing scenario, both scientific and
strategic, has led us to propose it for the starting winter
campaign of at the Concordia Base. Here the instrument and the
features making it suitable to operate at Dome-C are described.
After the initial setup, BaR-SPOrt should not require any kind of
routine intervention by a dedicated base staff. The experiment
will just need electrical power (less than 2 kW) and a suitable
accommodation on the field. It can be fully monitored and
controlled, including the data acquisition, through its own
telemetry/telecommand link using IRIDIUM modems. Both the receiver
and the critical electronics are housed inside a
temperature-controlled vacuum chamber, providing the properly
stabilized environment. The cold part of the radiometer employs a
closed loop mechanical cryo-cooler that provides temperatures <70 ± 0.1 K with low power consumption (<200 W).
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