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1.
Phys Rev Lett ; 132(2): 021001, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38277596

RESUMO

We show, for the first time, radio measurements of the depth of shower maximum (X_{max}) of air showers induced by cosmic rays that are compared to measurements of the established fluorescence method at the same location. Using measurements at the Pierre Auger Observatory we show full compatibility between our radio and the previously published fluorescence dataset, and between a subset of air showers observed simultaneously with both radio and fluorescence techniques, a measurement setup unique to the Pierre Auger Observatory. Furthermore, we show radio X_{max} resolution as a function of energy and demonstrate the ability to make competitive high-resolution X_{max} measurements with even a sparse radio array. With this, we show that the radio technique is capable of cosmic-ray mass composition studies, both at Auger and at other experiments.

2.
Phys Rev Lett ; 131(1): 015102, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37478441

RESUMO

In the dynamic-shell (DS) concept [V. N. Goncharov et al., Novel Hot-Spot Ignition Designs for Inertial Confinement Fusion with Liquid-Deuterium-Tritium Spheres, Phys. Rev. Lett. 125, 065001 (2020).PRLTAO0031-900710.1103/PhysRevLett.125.065001] for laser-driven inertial confinement fusion the deuterium-tritium fuel is initially in the form of a homogeneous liquid inside a wetted-foam spherical shell. This fuel is ignited using a conventional implosion, which is preceded by a initial compression of the fuel followed by its expansion and dynamic formation of a high-density fuel shell with a low-density interior. This Letter reports on a scaled-down, proof-of-principle experiment on the OMEGA laser demonstrating, for the first time, the feasibility of DS formation. A shell is formed by convergent shocks launched by laser pulses at the edge of a plasma sphere, with the plasma itself formed as a result of laser-driven compression and relaxation of a surrogate plastic-foam ball target. Three x-ray diagnostics, namely, 1D spatially resolved self-emission streaked imaging, 2D self-emission framed imaging, and backlighting radiography, have shown good agreement with the predicted evolution of the DS and its stability to low Legendre mode perturbations introduced by laser irradiation and target asymmetries.

3.
Phys Rev Lett ; 130(6): 061001, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36827568

RESUMO

Instantons, which are nonperturbative solutions to Yang-Mills equations, provide a signal for the occurrence of quantum tunneling between distinct classes of vacua. They can give rise to decays of particles otherwise forbidden. Using data collected at the Pierre Auger Observatory, we search for signatures of such instanton-induced processes that would be suggestive of super-heavy particles decaying in the Galactic halo. These particles could have been produced during the post-inflationary epoch and match the relic abundance of dark matter inferred today. The nonobservation of the signatures searched for allows us to derive a bound on the reduced coupling constant of gauge interactions in the dark sector: α_{X}≲0.09, for 10^{9}≲M_{X}/GeV<10^{19}. Conversely, we obtain that, for instance, a reduced coupling constant α_{X}=0.09 excludes masses M_{X}≳3×10^{13} GeV. In the context of dark matter production from gravitational interactions alone, we illustrate how these bounds are complementary to those obtained on the Hubble rate at the end of inflation from the nonobservation of tensor modes in the cosmological microwave background.

4.
Phys Rev Lett ; 128(19): 195002, 2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35622051

RESUMO

This Letter presents the first observation on how a strong, 500 kG, externally applied B field increases the mode-two asymmetry in shock-heated inertial fusion implosions. Using a direct-drive implosion with polar illumination and imposed field, we observed that magnetization produces a significant increase in the implosion oblateness (a 2.5× larger P2 amplitude in x-ray self-emission images) compared with reference experiments with identical drive but with no field applied. The implosions produce strongly magnetized electrons (ω_{e}τ_{e}≫1) and ions (ω_{i}τ_{i}>1) that, as shown using simulations, restrict the cross field heat flow necessary for lateral distribution of the laser and shock heating from the implosion pole to the waist, causing the enhanced mode-two shape.

6.
Phys Rev Lett ; 126(20): 201102, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34110215

RESUMO

The measurement of the energy spectrum of cosmic ray helium nuclei from 70 GeV to 80 TeV using 4.5 years of data recorded by the Dark Matter Particle Explorer (DAMPE) is reported in this work. A hardening of the spectrum is observed at an energy of about 1.3 TeV, similar to previous observations. In addition, a spectral softening at about 34 TeV is revealed for the first time with large statistics and well controlled systematic uncertainties, with an overall significance of 4.3σ. The DAMPE spectral measurements of both cosmic protons and helium nuclei suggest a particle charge dependent softening energy, although with current uncertainties a dependence on the number of nucleons cannot be ruled out.

7.
Nat Commun ; 12(1): 2679, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976145

RESUMO

Turbulence is ubiquitous in the universe and in fluid dynamics. It influences a wide range of high energy density systems, from inertial confinement fusion to astrophysical-object evolution. Understanding this phenomenon is crucial, however, due to limitations in experimental and numerical methods in plasma systems, a complete description of the turbulent spectrum is still lacking. Here, we present the measurement of a turbulent spectrum down to micron scale in a laser-plasma experiment. We use an experimental platform, which couples a high power optical laser, an x-ray free-electron laser and a lithium fluoride crystal, to study the dynamics of a plasma flow with micrometric resolution (~1µm) over a large field of view (>1 mm2). After the evolution of a Rayleigh-Taylor unstable system, we obtain spectra, which are overall consistent with existing turbulent theory, but present unexpected features. This work paves the way towards a better understanding of numerous systems, as it allows the direct comparison of experimental results, theory and numerical simulations.

8.
Opt Express ; 29(8): 12240-12251, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33984988

RESUMO

In a recent experimental campaign, we used laser-accelerated relativistic hot electrons to ensure heating of thin titanium wire targets up to a warm dense matter (WDM) state [EPL114, 45002 (2016)10.1209/0295-5075/114/45002]. The WDM temperature profiles along several hundred microns of the wire were inferred by using spatially resolved X-ray emission spectroscopy looking at the Ti Kα characteristic lines. A maximum temperature of ∼30 eV was reached. Our study extends this work by discussing the influence of the laser parameters on temperature profiles and the optimisation of WDM wire-based generation. The depth of wire heating may reach several hundreds of microns and it is proven to be strictly dependent on the laser intensity. At the same time, it is quantitatively demonstrated that the maximum WDM temperature doesn't appear to be sensitive to the laser intensity and mainly depends on the deposited laser energy considering ranges of 6×1018-6×1020 W/cm2 and 50-200 J.

9.
Phys Rev Lett ; 126(15): 152002, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33929235

RESUMO

We present the first measurement of the fluctuations in the number of muons in extensive air showers produced by ultrahigh energy cosmic rays. We find that the measured fluctuations are in good agreement with predictions from air shower simulations. This observation provides new insights into the origin of the previously reported deficit of muons in air shower simulations and constrains models of hadronic interactions at ultrahigh energies. Our measurement is compatible with the muon deficit originating from small deviations in the predictions from hadronic interaction models of particle production that accumulate as the showers develop.

10.
J Endocrinol Invest ; 44(1): 165-171, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32385852

RESUMO

BACKGROUND: The familial nonmedullary thyroid cancer (FNMTC) is suspected to be a Mendelian condition in up to 3-8% of thyroid cancers. The susceptibility chromosomal loci and genes of 95% of FNMTC cases remain to be characterized. The inheritance of FNMTC appears to be autosomal dominant with incomplete penetrance and variable expressivity. The finding of the causative gene of FNMTC and the identification of patients at risk that need genetic testing were our aim. METHODS: We analyzed by whole-exome sequencing patients and non-affected relatives of five families with at least two family members affected by papillary thyroid cancer, selecting for new or extremely rare variants with predicted pathogenic value. RESULTS: A family showed, in all three affected members, a new loss-of-function variant (frameshift deletion) in BROX gene at 1q41 that was absent from all internal and external databases. In a second family with three affected relatives, we found an additional new BROX variant. The smaller families presented no variants in BROX or in the other causative genes studied. CONCLUSIONS: BROX could be a new causative gene for FNMTC. Variants in BROX may result in the haploinsufficiency of a key gene involved in the morphogenesis of MVBs, in the endosomal sorting of cargo proteins, and in EGFR. Functional studies are needed to support this result. The thorough genomic analysis by NGS in all families with three or more affected members should become a routine approach to obtain a comprehensive genetic view and find confirmative second cases.


Assuntos
Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Haploinsuficiência , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Adulto , Feminino , Testes Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Câncer Papilífero da Tireoide/etiologia , Câncer Papilífero da Tireoide/metabolismo , Neoplasias da Glândula Tireoide/etiologia , Neoplasias da Glândula Tireoide/metabolismo
11.
Phys Rev Lett ; 125(12): 121106, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-33016715

RESUMO

We report a measurement of the energy spectrum of cosmic rays above 2.5×10^{18} eV based on 215 030 events. New results are presented: at about 1.3×10^{19} eV, the spectral index changes from 2.51±0.03(stat)±0.05(syst) to 3.05±0.05(stat)±0.10(syst), evolving to 5.1±0.3(stat)±0.1(syst) beyond 5×10^{19} eV, while no significant dependence of spectral features on the declination is seen in the accessible range. These features of the spectrum can be reproduced in models with energy-dependent mass composition. The energy density in cosmic rays above 5×10^{18} eV is [5.66±0.03(stat)±1.40(syst)]×10^{53} erg Mpc^{-3}.

12.
Sci Rep ; 10(1): 8100, 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32393805

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

14.
J Endocrinol Invest ; 43(1): 109-116, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31327128

RESUMO

BACKGROUND: Whether differentiated thyroid cancer (DTC) occurring concomitantly with Graves' disease (GD) is more aggressive and bound to a less favorable outcome is controversial. OBJECTIVE: Aim of this multicenter retrospective study was to compare baseline features and outcome of DTC patients with GD (DTC/GD+) or without GD (DTC/GD-). PATIENTS: Enrolled in this study were 579 patients referred to five endocrine units (Cagliari, Pavia, Pisa, Siena, and Varese) between 2005 and 2014: 193 patients had DTC/GD+ , 386 DTC/GD-. Patients were matched for age, gender and tumor size. They underwent surgery because of malignancy, large goiter size, or relapse of hyperthyroidism in GD. RESULTS: Baseline DTC features (histology, lymph node metastases, extrathyroidal extension) did not differ in the two groups, except for multifocality which was significantly more frequent in DTC/GD+ (27.5% vs. 7.5%, p < 0.0001). At the end of follow-up (median 7.5 years), 86% of DTC/GD+ and 89.6% DTC/GD- patients were free of disease. Patients with persistent or recurrent disease (PRD) had "biochemical disease" in the majority of cases. Microcarcinomas were more frequent in the DTC/GD+ group (60% vs. 37%, p < 0.0001) and had an excellent outcome, with no difference in PRD between groups. However, in carcinomas ≥ 1 cm, PRD was significantly more common in DTC/GD+ (24.4% vs. 11.5%; p = 0.005). In the whole group, univariate and multivariate analyses showed that GD+ , lymph node involvement, extrathyroidal invasion, multifocality and tall cell histotype were associated with a worse outcome. Female gender and microcarcinomas were favorable features. No association was found between baseline TSH-receptor antibody levels and outcome. Graves' orbitopathy (GO) seemed to be associated with a better outcome of DTC, possibly because patients with GO may early undergo surgery for hyperthyroidism. CONCLUSIONS: GD may be associated with a worse outcome of coexisting DTC only if cancer is ≥ 1 cm, whereas clinical outcome of microcarcinomas is not related to the presence/absence of GD.


Assuntos
Adenocarcinoma/mortalidade , Diferenciação Celular , Doença de Graves/complicações , Neoplasias da Glândula Tireoide/mortalidade , Tireoidectomia/mortalidade , Adenocarcinoma/etiologia , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Neoplasias da Glândula Tireoide/etiologia , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia
15.
Sci Rep ; 9(1): 18805, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31827132

RESUMO

X-ray phase contrast imaging (XPCI) is more sensitive to density variations than X-ray absorption radiography, which is a crucial advantage when imaging weakly-absorbing, low-Z materials, or steep density gradients in matter under extreme conditions. Here, we describe the application of a polychromatic X-ray laser-plasma source (duration ~0.5 ps, photon energy >1 keV) to the study of a laser-driven shock travelling in plastic material. The XPCI technique allows for a clear identification of the shock front as well as of small-scale features present during the interaction. Quantitative analysis of the compressed object is achieved using a density map reconstructed from the experimental data.

16.
J Endocrinol Invest ; 41(9): 1029-1035, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29470826

RESUMO

PURPOSE: According to American Thyroid Association (ATA) guideline, papillary thyroid cancer (PTC) with minimal extrathyroidal extension (mETE) is classified at "intermediate risk" of persistent/recurrent disease. However, the impact of mETE per se on patients' outcome is not fully understood. The aim of our study was to evaluate the prognostic significance of mETE in patients with PTC not submitted to therapeutic or prophylactic lymph node dissection, according to tumor size and other prognostic factors. PATIENTS AND METHODS: We retrospectively evaluated a total of 514 PTC patients: 127 (24.7%) had mETE (pT3Nx) and 387 (75.3%) had negative margins (pT1-2Nx). At a median follow-up of 9.1 years, patients were divided in two groups: patients with "good outcome" (no evidence of disease) and patients with "poor outcome" (persistent structural disease or recurrent disease or tumor-related death). RESULTS: The rate of patients with "poor outcome" was significantly higher in patients with mETE compared with patients with negative margins (11.8 versus 5.1%; OR 2.4576, 95% CI 1.2178-4.9594, p = 0.01). However, mETE was significantly associated with poor outcome only in patients with tumors larger than 1.5 cm. CONCLUSIONS: mETE is an unfavorable prognostic factor in tumors larger than 1.5 cm, suggesting that, in the absence of other unfavorable characteristics, smaller tumors with mETE should be classified and managed as "low risk" tumors.


Assuntos
Gerenciamento Clínico , Guias de Prática Clínica como Assunto/normas , Câncer Papilífero da Tireoide/diagnóstico , Câncer Papilífero da Tireoide/cirurgia , Tireoidectomia/normas , Instituições Filantrópicas de Saúde/normas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Câncer Papilífero da Tireoide/classificação , Tireoidectomia/métodos , Adulto Jovem
17.
Clin Ter ; 168(3): e208-e213, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28612899

RESUMO

Miller Fisher syndrome (MFS) is considered to be an uncommon variant of Guillain-Barré Syndrome. The disease is clinically characterized by acute ataxia of limbs, areflexia and ophthalmoplegia, although the set of symptoms and signs can be quite heterogeneous, with a benign and monophasic course. We describe a case of recurrent MFS where there have been four clinical episodes occurred with complete remission after each relapse. Last recurrence was treated with oral steroids. The reported frequency of recurrent MFS in literature is variable as well as the best treatment in these cases. We add a new case treated with steroid and we perform a review of the literature.


Assuntos
Síndrome de Miller Fisher , Feminino , Humanos , Masculino , Síndrome de Miller Fisher/tratamento farmacológico , Recidiva , Esteroides/uso terapêutico
18.
Biomed Res Int ; 2016: 1295329, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27563661

RESUMO

Patients with hepatocellular carcinoma (HCC) comply with an advanced disease and are not eligible for radical therapy. In this distressed scenario new treatment options hold great promise; among them transarterial chemoembolization (TACE) and transarterial metabolic radiotherapy (TAMR) have shown efficacy in terms of both tumor shrinking and survival. External radiation therapy (RTx) by using novel three-dimensional conformal radiotherapy has also been used for HCC patients with encouraging results while its role had been limited in the past for the low tolerance of surrounding healthy liver. The rationale of TAMR derives from the idea of delivering exceptional radiation dose locally to the tumor, with cell killing intent, while preserving normal liver from undue exposition and minimizing systemic irradiation. Since the therapeutic efficacy of TACE is being continuously disputed, the TAMR with (131)I Lipiodol or (90)Y microspheres has gained consideration providing adequate therapeutic responses regardless of few toxicities. The implementation of novel radioisotopes and technological innovations in the field of RTx constitutes an intriguing field of research with important translational aspects. Moreover, the combination of different therapeutic approaches including chemotherapy offers captivating perspectives. We present the role of the radiation-based therapies in hepatocellular carcinoma patients who are not entitled for radical treatment.


Assuntos
Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Quimiorradioterapia/métodos , Neoplasias Hepáticas/terapia , Carcinoma Hepatocelular/patologia , Humanos , Fígado/patologia , Neoplasias Hepáticas/patologia
19.
Rev Sci Instrum ; 87(1): 013504, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26827318

RESUMO

In this paper, a preliminary shadowgraph-based analysis of dust particles re-suspension due to loss of vacuum accident (LOVA) in ITER-like nuclear fusion reactors has been presented. Dust particles are produced through different mechanisms in nuclear fusion devices, one of the main issues is that dust particles are capable of being re-suspended in case of events such as LOVA. Shadowgraph is based on an expanded collimated beam of light emitted by a laser or a lamp that emits light transversely compared to the flow field direction. In the STARDUST facility, the dust moves in the flow, and it causes variations of refractive index that can be detected by using a CCD camera. The STARDUST fast camera setup allows to detect and to track dust particles moving in the vessel and then to obtain information about the velocity field of dust mobilized. In particular, the acquired images are processed such that per each frame the moving dust particles are detected by applying a background subtraction technique based on the mixture of Gaussian algorithm. The obtained foreground masks are eventually filtered with morphological operations. Finally, a multi-object tracking algorithm is used to track the detected particles along the experiment. For each particle, a Kalman filter-based tracker is applied; the particles dynamic is described by taking into account position, velocity, and acceleration as state variable. The results demonstrate that it is possible to obtain dust particles' velocity field during LOVA by automatically processing the data obtained with the shadowgraph approach.

20.
Nat Prod Res ; 30(2): 185-91, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26222766

RESUMO

Digestate coming from an Anaerobic Digestion unit in a Biogas Plant, feeded on cow manure and vegetable waste from markets, has been used. About 8-35 L polyethylene transparent bags have been employed as cultivation container, outdoor. Different aliquots of digestate, alone or mixed with commercial liquid fertiliser, were employed to cultivate in batch Scenedesus dimorphus, a freshwater green microalga, in the ENEA facilities of Casaccia Research Center, near Rome, Italy. The cultivation period was June-July 2013. The average daily yields of dry microalgae biomass varied from 20 mg/L/d to 60 mg/L/d, mean 38.2 mg/L/d. Final dry biomass concentration varied from 0.18 to 1.29 g/L, mean 0.55 g/L. S. dimorphus proved to be very efficient in removing N and P from the culture medium. Another fact emerged from these trials is that S. dimorphus inner composition resulted to be variable in response to the tested different culture conditions.


Assuntos
Biocombustíveis , Fotobiorreatores , Scenedesmus/crescimento & desenvolvimento , Anaerobiose , Animais , Biomassa , Bovinos , Desenho de Equipamento , Feminino , Água Doce , Itália , Esterco , Microalgas/crescimento & desenvolvimento , Microalgas/metabolismo , Scenedesmus/metabolismo , Técnicas de Cultura de Tecidos/métodos
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