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1.
Ann Ig ; 34(6): 603-618, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35076653

RESUMO

Background: "Life-course immunization" is increasingly recognized as important. In Italy, adults are recommended to receive influenza; pneumococcal; tetanus toxoid, reduced diphtheria toxoid, acellular pertussis (Tdap); and herpes zoster (HZ) vaccines at various ages. Study design: Cross-sectional study. Methods: To study the knowledge and attitudes of Italian general practitioners (GPs) towards adult vaccination, we surveyed 335 GPs in Piedmont from December 2019 through March 2020; and compared the results by GPs' age (≤50 vs >50 years). Results: The most common vaccination information source was the regional/local educational courses (72.8%), with older vs younger GPs more likely to attend (79.4% vs 64.4%; p=0.002). Approximately half felt that they needed further information on vaccine co-administration (55.5%), duration of protection (49.6%), and safety/tolerability (48.7%), with older vs younger GPs being more interested in safety/tolerability. Overall, most respondents (86.0%) felt that information for the patient would most engage them, and 68.1% planned to co-administer vaccines. Respondents felt most comfortable proposing influenza, but were also comfortable about pneumococcal/Tdap/HZ vaccination. However, younger vs older GPs were more comfortable about proposing Tdap and HZ. The most common ways to inform patients about influenza or pneumococcal/Tdap/HZ vaccination eligibility were personally during a visit (42.7% or 54.3%, respectively) or via an information poster (30.7% or 17.9%). Conclusions: The surveyed GPs had favorable attitudes towards adult vaccination and were interested in ongoing education.


Assuntos
Clínicos Gerais , Vacina contra Herpes Zoster , Vacinas contra Influenza , Influenza Humana , Coqueluche , Adulto , Atitude , Estudos Transversais , Humanos , Influenza Humana/prevenção & controle , Pessoa de Meia-Idade , Vacina contra Coqueluche , Vacinas Pneumocócicas , Vacinação , Coqueluche/prevenção & controle
2.
Sci Total Environ ; 590-591: 799-808, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28291610

RESUMO

The 1999 Mw 7.4 earthquake triggered a tremendous human tragedy and had a great social impact over the population of the Izmit Bay, one of the most industrialized area of Turkey. Although the successive environmental disasters were well documented, information on its sedimentary record is lacking. The present research aims at filling this gap, through the analysis of organic contaminants (PCBs, PAHs, and PBDEs) in a dated sediment core collected in the depocenter of the Karamürsel Basin in 2005. Profiles of total PCBs and total PAHs overlap the timing of industrialization in the area (starting in the 1960s) with values increasing as the population and the number of industrial plants grew larger. Profiles for PBDEs are in accordance with increasing urban inputs but are probably affected by processes of natural formation and post-depositional mixing. The continuous sedimentary record is interrupted at a level dating back to 1980 due to the erosion caused by the 1999 earthquake, having removed a 5-7cm thick sediment layer. Contaminant concentrations in the deepest 10-15cm of a 30cm thick seismo-turbidite unit, triggered by the 1999 event, increase with the progressive fining up and evidence massive transport of sediments from coastal, more polluted sites of the north-eastern Karamürsel shelves and shores. Additional inputs of PAHs are also evident, originating from a fire at the oil refinery that followed the shaking. The effects of the earthquake generated tsunami, its backwash fluxes and the following seiches are not uniquely displayed by each class of contaminants, and they could probably reflect successive inputs deriving from different parts of the basin that are subject to anthropogenic impacts of different nature. Concentrations measured at the top of the core are consistent with an unvaried input of pollutants in the period 1980-2005.

3.
Blood Cancer J ; 6(6): e439, 2016 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-27341078

RESUMO

microRNAs (miRNAs) are relevant in the pathogenesis of primary myelofibrosis (PMF) but our understanding is limited to specific target genes and the overall systemic scenario islacking. By both knowledge-based and ab initio approaches for comparative analysis of CD34+ cells of PMF patients and healthy controls, we identified the deregulated pathways involving miRNAs and genes and new transcriptional and post-transcriptional regulatory circuits in PMF cells. These converge in a unique and integrated cellular process, in which the role of specific miRNAs is to wire, co-regulate and allow a fine crosstalk between the involved processes. The PMF pathway includes Akt signaling, linked to Rho GTPases, CDC42, PLD2, PTEN crosstalk with the hypoxia response and Calcium-linked cellular processes connected to cyclic AMP signaling. Nested on the depicted transcriptional scenario, predicted circuits are reported, opening new hypotheses. Links between miRNAs (miR-106a-5p, miR-20b-5p, miR-20a-5p, miR-17-5p, miR-19b-3p and let-7d-5p) and key transcription factors (MYCN, ATF, CEBPA, REL, IRF and FOXJ2) and their common target genes tantalizingly suggest new path to approach the disease. The study provides a global overview of transcriptional and post-transcriptional deregulations in PMF, and, unifying consolidated and predicted data, could be helpful to identify new combinatorial therapeutic strategy. Interactive PMF network model: http://compgen.bio.unipd.it/pmf-net/.


Assuntos
MicroRNAs/genética , Proteínas de Neoplasias/genética , Mielofibrose Primária/genética , Processamento Pós-Transcricional do RNA , Idoso , Idoso de 80 Anos ou mais , Antígenos CD34/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Mielofibrose Primária/patologia , Transdução de Sinais , Transcrição Gênica
4.
J Phys Condens Matter ; 27(32): 326002, 2015 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-26213808

RESUMO

We have carried out measurements of domain wall dynamics in a Pt/Co/GdOx(t) wedge sample with perpendicular magnetic anisotropy. When driven by an easy-axis field Hz in the presence of an in-plane field Hx, the domain wall propagation is different along [Formula: see text]x, as expected for samples presenting Dzyaloshinskii-Moriya (DMI) interaction. In the creep regime, the sign and the value of the domain wall velocity asymmetry changes along the wedge. We show that in our samples the domain wall speed versus Hx curves in the creep regime cannot be explained simply in terms of the variation of the domain wall energy with Hx, as suggested by previous works. For this reason the strength and the sign of the DMI cannot be extracted from these measurements. To obtain reliable information on the DMI strength using magnetic field-induced domain wall dynamics, measurements have been performed with high fields, bringing the DW close to the flow regime of propagation. In this case we find large values of the DMI, consistent in magnitude and sign with those obtained from Brillouin light scattering measurements.

5.
Sci Rep ; 5: 12417, 2015 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-26201268

RESUMO

Magnetic domain walls (DWs) in nanostructures are low-dimensional objects that separate regions with uniform magnetisation. Since they can have different shapes and widths, DWs are an exciting playground for fundamental research, and became in the past years the subject of intense works, mainly focused on controlling, manipulating, and moving their internal magnetic configuration. In nanostrips with in-plane magnetisation, two DWs have been identified: in thin and narrow strips, transverse walls are energetically favored, while in thicker and wider strips vortex walls have lower energy. The associated phase diagram is now well established and often used to predict the low-energy magnetic configuration in a given magnetic nanostructure. However, besides the transverse and vortex walls, we find numerically that another type of wall exists in permalloy nanostrips. This third type of DW is characterised by a three-dimensional, flux closure micromagnetic structure with an unusual length and three internal degrees of freedom. Magnetic imaging on lithographically-patterned permalloy nanostrips confirms these predictions and shows that these DWs can be moved with an external magnetic field of about 1 mT. An extended phase diagram describing the regions of stability of all known types of DWs in permalloy nanostrips is provided.

6.
Phys Rev Lett ; 113(4): 047203, 2014 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-25105650

RESUMO

The nucleation of reversed magnetic domains in Pt/Co/AlO(x) microstructures with perpendicular anisotropy was studied experimentally in the presence of an in-plane magnetic field. For large enough in-plane field, nucleation was observed preferentially at an edge of the sample normal to this field. The position at which nucleation takes place was observed to depend in a chiral way on the initial magnetization and applied field directions. A quantitative explanation of these results is proposed, based on the existence of a sizable Dzyaloshinskii-Moriya interaction in this sample. Another consequence of this interaction is that the energy of domain walls can become negative for in-plane fields smaller than the effective anisotropy field.

7.
Phys Rev Lett ; 111(21): 217203, 2013 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-24313522

RESUMO

We show that the Dzyaloshinskii-Moriya interaction (DMI) can lead to a tilting of the domain wall (DW) surface in perpendicularly magnetized magnetic nanotracks when DW dynamics are driven by an easy axis magnetic field or a spin polarized current. The DW tilting affects the DW dynamics for large DMI, and the tilting relaxation time can be very large as it scales with the square of the track width. The results are well explained by an extended collective coordinate model where DMI and DW tilting are included. We propose a simple way to estimate the DMI in magnetic multilayers by measuring the dependence of the DW tilt angle on a transverse static magnetic field. These results shed light on the current induced DW tilting observed recently in Co/Ni multilayers with structural inversion asymmetry.

8.
Phys Rev Lett ; 108(24): 247202, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23004314

RESUMO

Domain wall motion induced by nanosecond current pulses in nanostripes with perpendicular magnetic anisotropy (Pt/Co/AlO(x)) is shown to exhibit negligible inertia. Time-resolved magnetic microscopy during current pulses reveals that the domain walls start moving, with a constant speed, as soon as the current reaches a constant amplitude, and no or little motion takes place after the end of the pulse. The very low "mass" of these domain walls is attributed to the combination of their narrow width and high damping parameter α. Such a small inertia should allow accurate control of domain wall motion by tuning the duration and amplitude of the current pulses.

9.
J Phys Condens Matter ; 24(2): 024213, 2012 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-22173430

RESUMO

Current-induced domain wall motion and magnetization dynamics in the CoFeB layer of CoFeB/Cu/Co nanostripes were studied using photoemission electron microscopy combined with x-ray magnetic circular dichroism (XMCD-PEEM). Quasi-static measurements show that current-induced domain wall motion in the CoFeB layer is similar to the one observed in the NiFe layer of NiFe/Cu/Co trilayers, although the threshold current densities for domain wall depinning are lower. Time-resolved XMCD-PEEM measurements are used as an efficient probe of domain wall depinning statistics. They also reveal that, during the application of current pulses, the CoFeB magnetization rotates in the direction transverse to the nanostripe. The corresponding tilt angles have been quantified and compared to analytical and micromagnetic calculations, highlighting the influence of magnetostatic interactions between the two magnetic layers on the magnetization rotation.

10.
Phys Rev Lett ; 96(9): 097204, 2006 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-16606309

RESUMO

The dynamics of magnetic domain wall motion in the FeNi layer of a FeNi/Al2O3/Co trilayer has been investigated by a combination of x-ray magnetic circular dichroism, photoelectron emission microscopy, and a stroboscopic pump-probe technique. The nucleation of domains and subsequent expansion by domain wall motion in the FeNi layer during nanosecond-long magnetic field pulses was observed in the viscous regime up to the Walker limit field. We attribute an observed delay of domain expansion to the influence of the domain wall energy that acts against the domain expansion and that plays an important role when domains are small.

11.
Phys Rev Lett ; 95(7): 076401, 2005 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-16196803

RESUMO

Theory, models, and experimental phenomena provide evidence of the existence of shallow bands in silicon induced by the dislocation strain field. Nevertheless, only deep bands, likely associated with contamination at dislocations, have been detected up to now by junction spectroscopy. Here we present the first experimental result by junction spectroscopy that assesses the existence of the dislocation related shallow states. These are found to be located at 70 and 60 meV from the valence and conduction band edge, respectively.

12.
Phys Rev Lett ; 91(2): 027201, 2003 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-12906504

RESUMO

An in-plane perpendicular magnetic coupling between Ni80Fe20 and Co has been found in NiFe/NiO/Co trilayers for a NiO thickness ranging from 4 to 25 nm by magneto-optical Kerr effect and x-ray magnetic circular dichroism measurements. In the easy magnetization direction of the Co layer, the Co coercive field H(C) increases when the thickness of the NiO layer t(NiO) increases. Because of the coupling, H(C) is always larger than for NiO/Co bilayers with the same thicknesses. The saturation field of the NiFe layer H(S) decreases when t(NiO) increases, indicating a weakening of the coupling. Numerical simulations show that the presence of interface roughness combined with a small value of the NiO anisotropy can explain the observed 90 degrees coupling.

13.
J Synchrotron Radiat ; 8(Pt 2): 443-5, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11512808

RESUMO

We present X-ray Magnetic Circular Dichroism experiments (XMCD) on the Fe K edge of FeZrB metallic glasses performed under tensile stress. In these compounds the application of tensile stresses produces a large increase of the Curie Temperature. The XMCD signal presents the features expected for a weak ferromagnet but a gradual enhancement of the ferromagnetism is observed as boron and zirconium concentrations increase. The main effect of the tensile stress is to increase the density of states at the Fermi level as deduced from the increment of the amplitude of the XMCD signal with the stress.

14.
Phys Rev Lett ; 86(16): 3646-9, 2001 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-11328044

RESUMO

We have developed a new original technique to study the magnetization reversal dynamics of thin films with element selectivity in the nanosecond time scale. X-ray magnetic circular dichroism measurements in pump-probe mode are carried out taking advantage of the time structure of synchrotron radiation. The dynamics of the magnetization reversal of each of the layers of complex heterostructures (like spin valves or tunnel junctions) can be probed independently. The interlayer coupling in the studied systems has been shown to play a key role in the determination of the magnetization reversal of each individual layer.

16.
J Synchrotron Radiat ; 5(Pt 3): 750-2, 1998 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-15263641

RESUMO

The one-bunch filling mode of the ESRF is combined with a microcoil to generate a pulsed-magnetic-field pump phased with respect to the probe that is given by the bunch of photons emitted each turn (357 kHz). Nanosecond-resolved X-ray magnetic circular dichroism (XMCD) is carried out. Besides the microcoil, the two other key-elements are the energy-dispersive XAS spectrometer, which yields parallel data acquisition, and the diamond-based quarter-wave plate, which tunes the helicity of the photon alternatively left and right.

17.
J Synchrotron Radiat ; 5(Pt 3): 992-4, 1998 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-15263722

RESUMO

This paper reports on two new technical developments concerning sample environments for X-ray magnetic circular dichroism (XMCD). The first measurements under high pressures of up to 30 GPa are described. The difficulties of combining the techniques of high pressure and XMCD are commented on. The second development involves the use of a fast-switching magnetic field. A new superconducting device is used to perform XMCD measurements on paramagnetic compounds in magnetic fields of up to 6 T. The small amplitude of the XMCD signal imposes, for a given signal-to-noise ratio, a noise less than a few 10(-5). The signal-to-noise ratio is improved by the use of a series of acquisitions, switching the magnetic field between each acquisition. A very fast switching mechanism has been built based on mechanical rotation of a superconducting coil, with the sample kept in place inside the coil. The XMCD signals at the L(II,III)-edges of paramagnetic rare-earth compounds have been measured at 4.5 K in fields of up to 6 T with a switching time of 11 s.

18.
J Synchrotron Radiat ; 5(Pt 5): 1298-303, 1998 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16687837

RESUMO

The first XMCD measurements carried out on the ID24 energy-dispersive XAS beamline at the ESRF are reported. Circular-polarized X-rays are obtained using perfect diamond crystals as quarter-wave plates. The very small source divergence allows circular polarizations close to unity to be obtained.

20.
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