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1.
Psychon Bull Rev ; 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38528302

RESUMEN

Most models of language comprehension assume that the linguistic system is able to pre-activate phonological information. However, the evidence for phonological prediction is mixed and controversial. In this study, we implement a paradigm that capitalizes on the fact that foreign speakers usually make phonological errors. We investigate whether speaker identity (native vs. foreign) is used to make specific phonological predictions. Fifty-two participants were recruited to read sentence frames followed by a last spoken word which was uttered by either a native or a foreign speaker. They were required to perform a lexical decision on the last spoken word, which could be either semantically predictable or not. Speaker identity (native vs. foreign) may or may not be cued by the face of the speaker. We observed that the face cue is effective in speeding up the lexical decision when the word is predictable, but it is not effective when the word is not predictable. This result shows that speech prediction takes into account the phonological variability between speakers, suggesting that it is possible to pre-activate in a detailed and specific way the phonological representation of a predictable word.

2.
Phys Rev Lett ; 132(6): 066004, 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38394564

RESUMEN

We have investigated the 3d orbital excitations in CaCuO_{2} (CCO), Nd_{2}CuO_{4} (NCO), and La_{2}CuO_{4} (LCO) using high-resolution resonant inelastic x-ray scattering. In LCO they behave as well-localized excitations, similarly to several other cuprates. On the contrary, in CCO and NCO the d_{xy} orbital clearly disperses, pointing to a collective character of this excitation (orbiton) in compounds without apical oxygen. We ascribe the origin of the dispersion as stemming from a substantial next-nearest-neighbor (NNN) orbital superexchange. Such an exchange leads to the liberation of the orbiton from its coupling to magnons, which is associated with the orbiton hopping between nearest neighbor copper sites. Finally, we show that the exceptionally large NNN orbital superexchange can be traced back to the absence of apical oxygens suppressing the charge transfer energy.

3.
Nat Commun ; 14(1): 7198, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37938250

RESUMEN

The universality of the strange metal phase in many quantum materials is often attributed to the presence of a quantum critical point (QCP), a zero-temperature phase transition ruled by quantum fluctuations. In cuprates, where superconductivity hinders direct QCP observation, indirect evidence comes from the identification of fluctuations compatible with the strange metal phase. Here we show that the recently discovered charge density fluctuations (CDF) possess the right properties to be associated to a quantum phase transition. Using resonant x-ray scattering, we studied the CDF in two families of cuprate superconductors across a wide doping range (up to p = 0.22). At p* ≈ 0.19, the putative QCP, the CDF intensity peaks, and the characteristic energy Δ is minimum, marking a wedge-shaped region in the phase diagram indicative of a quantum critical behavior, albeit with anomalies. These findings strengthen the role of charge order in explaining strange metal phenomenology and provide insights into high-temperature superconductivity.

4.
ACS Appl Eng Mater ; 1(7): 1937-1945, 2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37533604

RESUMEN

Copper (Cu) is the electrical conductor of choice in many categories of electrical wiring, with household and building installation being the major market of this metal. This work demonstrates the coating of Cu wires-with diameters relevant for low-voltage (LV) applications-with graphene. The chemical vapor deposition (CVD) coating process is rapid, safe, scalable, and industrially compatible. Graphene-coated Cu wires display good oxidation resistance and increased electrical conductivity (up to 1% immediately after coating and up to 3% after 24 months), allowing for wire diameter reduction and thus significant savings in wire production costs. Combined spectroscopic and diffraction analysis indicates that the conductivity increase is due to a change in Cu crystallinity induced by the coating process conditions, while electrical testing of aged wires shows that graphene plays a major role in maintaining improved electrical performances over long periods of time. Finally, graphene coating of Cu wires using an ambient-pressure roll-to-roll (R2R) CVD reactor is demonstrated. This enables the in-line production of graphene-coated metallic wires as required for industrial scale-up.

5.
Front Med (Lausanne) ; 8: 621668, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33718402

RESUMEN

Acute rheumatic fever (ARF) is a non-septic complication of group A ß-hemolytic streptococcal (GAS) throat infection. Since 1944, ARF diagnosis relies on the Jones criteria, which were periodically revised. The 2015 revision of Jones criteria underlines the importance of knowing the epidemiological status of its own region with updated data. This study aims to describe ARF features in a retrospective cohort retrieved over a 10-year timespan (2009-2018) and to report the annual incidence of ARF among children in the Province of Monza-Brianza, Lombardy, Italy during the same period. This is a multicentric cross-sectional/retrospective study; 70 patients (39 boys) were diagnosed with ARF. The median age at diagnosis was 8.5 years (range, 4-14.2 years). Overall, carditis represented the most reported major Jones criteria followed by arthritis and chorea (40, 27, and 20 cases, respectively). In order to calculate the annual incidence of ARF, only children resident in the Province of Monza-Brianza were included in this part of the analysis. Therefore, 47 patients aged between 5 and 14 years were identified. The median incidence during the study time was 5.7/100,000 (range, 2.8-8.3/100,000). In the Province of Monza-Brianza, we found an incidence rate of ARF among children aged 5-14 years constantly above the threshold of low-risk area as defined in the 2015 revision of Jones criteria. Therefore, the diagnosis of ARF should be based on the moderate-high-risk set of Jones criteria. However, given the burden of secondary prophylaxis, expert opinion is advisable when the diagnosis of ARF is uncertain.

6.
Nanomaterials (Basel) ; 10(4)2020 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-32344792

RESUMEN

Epitaxial films of high critical temperature ( T c ) cuprate superconductors preserve their transport properties even when their thickness is reduced to a few nanometers. However, when approaching the single crystalline unit cell (u.c.) of thickness, T c decreases and eventually, superconductivity is lost. Strain originating from the mismatch with the substrate, electronic reconstruction at the interface and alteration of the chemical composition and of doping can be the cause of such changes. Here, we use resonant inelastic x-ray scattering at the Cu L 3 edge to study the crystal field and spin excitations of NdBa 2 Cu 3 O 7 - x ultrathin films grown on SrTiO 3 , comparing 1, 2 and 80 u.c.-thick samples. We find that even at extremely low thicknesses, the strength of the in-plane superexchange interaction is mostly preserved, with just a slight decrease in the 1 u.c. with respect to the 80 u.c.-thick sample. We also observe spectroscopic signatures for a decrease of the hole-doping at low thickness, consistent with the expansion of the c-axis lattice parameter and oxygen deficiency in the chains of the first unit cell, determined by high-resolution transmission microscopy and x-ray diffraction.

7.
J Synchrotron Radiat ; 26(Pt 5): 1725-1732, 2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-31490164

RESUMEN

Resonant inelastic X-ray scattering (RIXS) is an extremely valuable tool for the study of elementary, including magnetic, excitations in matter. The latest developments of this technique have mostly been aimed at improving the energy resolution and performing polarization analysis of the scattered radiation, with a great impact on the interpretation and applicability of RIXS. Instead, this article focuses on the sample environment and presents a setup for high-pressure low-temperature RIXS measurements of low-energy excitations. The feasibility of these experiments is proved by probing the magnetic excitations of the bilayer iridate Sr3Ir2O7 at pressures up to 12 GPa.

8.
Phys Rev Lett ; 123(2): 027001, 2019 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-31386544

RESUMEN

We provide a novel experimental method to quantitatively estimate the electron-phonon coupling and its momentum dependence from resonant inelastic x-ray scattering (RIXS) spectra based on the detuning of the incident photon energy away from an absorption resonance. We apply it to the cuprate parent compound NdBa_{2}Cu_{3}O_{6} and find that the electronic coupling to the oxygen half-breathing phonon branch is strongest at the Brillouin zone boundary, where it amounts to ∼0.17 eV, in agreement with previous studies. In principle, this method is applicable to any absorption resonance suitable for RIXS measurements and will help to define the contribution of lattice vibrations to the peculiar properties of quantum materials.

9.
Res Dev Disabil ; 92: 103450, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31330443

RESUMEN

AIMS: This paper aims to describe the functioning profile of a clinical sample of patients with Cerebral Palsy at the time of transition. METHODS AND PROCEDURE: For this retrospective observational study, we considered data concerning 389 patients born from 1967 to 1997 with a diagnosis of CP and discharged at the age of 18 ±â€¯3 from "La Nostra Famiglia" Children Care Centres. We reported data concerning: identifiable risk factors, the type of CP, the level of motor, manual and communication abilities, the occurrence of associated impairments and environmental factors, and examine the trends over the decades. OUTCOME AND RESULTS: The disorder was mainly bilateral (86%): 57% of patients had quadriplegia and 43% had diplegia. Most of patients had a spastic disorder (86%). Comorbidities were frequent, mainly intellectual developmental disorder (63.5%). One fifth of patients showed a severe impairment of motor, manual and communicative skills in addition to a severe intellectual development disorder. Over decades, the outcome as expressed by the motor functioning profile improved but the outcome as expressed by the global functioning profile worsened because of the growing number of severe multi-disabilities. CONCLUSION AND IMPLICATION: Knowledge about the functioning profile of young adults with cerebral palsy can support health services in the provision of developmentally appropriate care.


Asunto(s)
Desarrollo del Adolescente , Parálisis Cerebral , Rendimiento Físico Funcional , Transición a la Atención de Adultos , Adolescente , Parálisis Cerebral/fisiopatología , Parálisis Cerebral/psicología , Parálisis Cerebral/rehabilitación , Evaluación de la Discapacidad , Femenino , Humanos , Masculino , Destreza Motora , Factores de Riesgo , Índice de Severidad de la Enfermedad , Habilidades Sociales , Adulto Joven
10.
J Nanosci Nanotechnol ; 19(8): 4980-4986, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-30913810

RESUMEN

Cobalt ferrite nanoparticles have been attracting considerable interest in the recent years because of the large number of potential applications, including magnetic storage, magnetic fluid hyperthermia and as contrast agents for magnetic resonance imaging. Physical properties of this class of materials depend critically on a number of parameters, including crystallinity, stoichiometry and cation distribution. In this work we have performed a Resonant Inelastic soft X-ray Scattering (RIXS) study on a series of 5 nm cobalt-doped maghemite nanoparticles to obtain direct quantitative information on cation distribution as a function of cobalt doping. We found that the distribution of divalent cobalt is stable in the investigated doping range and slightly different from that of bulk, stoichiometric cobalt ferrite. These results confirm that cobalt doping can be used to finely tune the magnetic properties of nanostructured ferrites without modifying their structural integrity.

11.
Front Immunol ; 9: 1387, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29971065

RESUMEN

Hematopoietic stem and progenitor cells (HSPCs) are multipotent stem cells that have been harnessed as a curative therapy for patients with hematological malignancies. Notably, the discovery that HSPCs are endowed with immunoregulatory properties suggests that HSPC-based therapeutic approaches may be used to treat autoimmune diseases. Indeed, infusion with HSPCs has shown promising results in the treatment of type 1 diabetes (T1D) and remains the only "experimental therapy" that has achieved a satisfactory rate of remission (nearly 60%) in T1D. Patients with newly diagnosed T1D have been successfully reverted to normoglycemia by administration of autologous HSPCs in association with a non-myeloablative immunosuppressive regimen. However, this approach is hampered by a high incidence of adverse effects linked to immunosuppression. Herein, we report that while the use of autologous HSPCs is capable of improving C-peptide production in patients with T1D, ex vivo modulation of HSPCs with prostaglandins (PGs) increases their immunoregulatory properties by upregulating expression of the immune checkpoint-signaling molecule PD-L1. Surprisingly, CXCR4 was upregulated as well, which could enhance HSPC trafficking toward the inflamed pancreatic zone. When tested in murine and human in vitro autoimmune assays, PG-modulated HSPCs were shown to abrogate the autoreactive T cell response. The use of PG-modulated HSPCs may thus provide an attractive and novel treatment of autoimmune diabetes.

12.
J Synchrotron Radiat ; 24(Pt 2): 545-546, 2017 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-28244452

RESUMEN

Corrections to the paper by Honkanen et al. (2014). [J. Synchrotron Rad. 21, 104-110] are made.

13.
Rev Sci Instrum ; 87(11): 115103, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27910538

RESUMEN

We have developed a helium gas flow cryostat for use on synchrotron tender to hard X-ray beamlines. Very efficient sample cooling is achieved because the sample is placed directly in the cooling helium flow on a removable sample holder. The cryostat is compact and easy to operate; samples can be changed in less than 5 min at any temperature. The cryostat has a temperature range of 2.5-325 K with temperature stability better than 0.1 K. The very wide optical angle and the ability to operate in any orientation mean that the cryostat can easily be adapted for different X-ray techniques. It is already in use on different beamlines at the European Synchrotron Radiation Facility (ESRF), ALBA Synchrotron Light Facility (ALBA), and Diamond Light Source (DLS) for inelastic X-ray scattering, powder diffraction, and X-ray absorption spectroscopy. Results obtained at these beamlines are presented here.

14.
Radiol. bras ; 49(6): 376-381, Nov.-Dec. 2016. tab, graf
Artículo en Inglés | LILACS | ID: biblio-842420

RESUMEN

Abstract Objective: The objective of this study was to profile patients who undergo defecography, by age and gender, as well as to describe the main imaging and diagnostic findings in this population. Materials and Methods: This was a retrospective, descriptive study of 39 patients, conducted between January 2012 and February 2014. The patients were evaluated in terms of age, gender, and diagnosis. They were stratified by age, and continuous variables are expressed as mean ± standard deviation. All possible quantitative defecography variables were evaluated, including rectal evacuation, perineal descent, and measures of the anal canal. Results: The majority (95%) of the patients were female. Patient ages ranged from 18 to 82 years (mean age, 52 ± 13 years): 10 patients were under 40 years of age; 18 were between 40 and 60 years of age; and 11 were over 60 years of age. All 39 of the patients evaluated had abnormal radiological findings. The most prevalent diagnoses were rectocele (in 77%) and enterocele (in 38%). Less prevalent diagnoses were vaginal prolapse, uterine prolapse, and Meckel's diverticulum (in 2%, for all). Conclusion: Although defecography is performed more often in women, both genders can benefit from the test. Defecography can be performed in order to detect complex disorders such as uterine and rectal prolapse, as well as to detect basic clinical conditions such as rectocele or enterocele.


Resumo Objetivo: Este estudo tem por objetivo descrever o perfil da população que se submeteu a exame de defecografia, de acordo com a faixa etária e sexo do paciente, bem como os principais achados e diagnósticos de imagem nesta população. Materiais e Métodos: Estudo retrospectivo e descritivo com 39 pacientes realizado entre janeiro de 2012 e fevereiro de 2014. Os pacientes foram avaliados quanto a idade, sexo e os diagnósticos encontrados. Foram divididos por idade, e as variáveis contínuas são expressas como média ± desvio-padrão. Todas as quantificações possíveis em defecografia foram realizadas neste trabalho, incluindo esvaziamento da ampola retal, descenso perineal e as medidas do canal anal. Resultados: Dos 39 pacientes estudados, todos apresentaram alterações radiológicas, sendo a maioria do sexo feminino (95%). O mais novo tinha 18 anos e o mais velho, 82 anos (idade média de 52 ± 13 anos). Dez pacientes tinham menos de 40 anos, 18 tinham entre 40 e 60 anos e 11 pacientes tinham mais do que 60 anos. Os diagnósticos mais prevalentes foram retocele anterior (77%) e enterocele (38%). Os menos frequentes foram prolapso vaginal (2%), prolapso uterino (2%) e divertículo de Meckel (2%). Conclusão: As mulheres realizam mais exames de defecografia, porém ambos os gêneros se beneficiam deste estudo. A defecografia é capaz de detectar causas complexas de distúrbio da defecação como prolapso vaginal, uterino e retal, e pode ser utilizada em condições clínicas mais simples como a avaliação de retocele ou enterocele.

15.
Proc Natl Acad Sci U S A ; 113(49): 13989-13994, 2016 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-27872287

RESUMEN

The second-order phase transition into a hidden order phase in URu2Si2 goes along with an order parameter that is still a mystery, despite 30 years of research. However, it is understood that the symmetry of the order parameter must be related to the symmetry of the low-lying local electronic [Formula: see text]-states. Here, we present results of a spectroscopic technique, namely core-level nonresonant inelastic X-ray scattering (NIXS). This method allows for the measurement of local high-multipole excitations and is bulk-sensitive. The observed anisotropy of the scattering function unambiguously shows that the 5[Formula: see text] ground-state wave function is composed mainly of the [Formula: see text] with majority [Formula: see text] = [Formula: see text] + [Formula: see text] and/or [Formula: see text] singlet states. The incomplete dichroism indicates the possibility that quantum states of other irreducible representation are mixed into the ground state.

18.
Sci Rep ; 6: 22648, 2016 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-26935531

RESUMEN

The Borrmann effect is the anomalous transmission of x-rays in perfect crystals under diffraction conditions. It arises from the interference of the incident and diffracted waves, which creates a standing wave with nodes at strongly absorbing atoms. Dipolar absorption of x-rays is thus diminished, which makes the crystal nearly transparent for certain x-ray wave vectors. Indeed, a relative enhancement of electric quadrupole absorption via the Borrmann effect has been demonstrated recently. Here we show that the Borrmann effect has a significantly larger impact on resonant x-ray emission than is observable in x-ray absorption. Emission from a dipole forbidden intermediate state may even dominate the corresponding x-ray spectra. Our work extends the domain of x-ray standing wave methods to resonant x-ray emission spectroscopy and provides means for novel spectroscopic experiments in d- and f-electron systems.

19.
Radiol Bras ; 49(6): 376-381, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28100932

RESUMEN

OBJECTIVE: The objective of this study was to profile patients who undergo defecography, by age and gender, as well as to describe the main imaging and diagnostic findings in this population. MATERIALS AND METHODS: This was a retrospective, descriptive study of 39 patients, conducted between January 2012 and February 2014. The patients were evaluated in terms of age, gender, and diagnosis. They were stratified by age, and continuous variables are expressed as mean ± standard deviation. All possible quantitative defecography variables were evaluated, including rectal evacuation, perineal descent, and measures of the anal canal. RESULTS: The majority (95%) of the patients were female. Patient ages ranged from 18 to 82 years (mean age, 52 ± 13 years): 10 patients were under 40 years of age; 18 were between 40 and 60 years of age; and 11 were over 60 years of age. All 39 of the patients evaluated had abnormal radiological findings. The most prevalent diagnoses were rectocele (in 77%) and enterocele (in 38%). Less prevalent diagnoses were vaginal prolapse, uterine prolapse, and Meckel's diverticulum (in 2%, for all). CONCLUSION: Although defecography is performed more often in women, both genders can benefit from the test. Defecography can be performed in order to detect complex disorders such as uterine and rectal prolapse, as well as to detect basic clinical conditions such as rectocele or enterocele.


OBJETIVO: Este estudo tem por objetivo descrever o perfil da população que se submeteu a exame de defecografia, de acordo com a faixa etária e sexo do paciente, bem como os principais achados e diagnósticos de imagem nesta população. MATERIAIS E MÉTODOS: Estudo retrospectivo e descritivo com 39 pacientes realizado entre janeiro de 2012 e fevereiro de 2014. Os pacientes foram avaliados quanto a idade, sexo e os diagnósticos encontrados. Foram divididos por idade, e as variáveis contínuas são expressas como média ± desvio-padrão. Todas as quantificações possíveis em defecografia foram realizadas neste trabalho, incluindo esvaziamento da ampola retal, descenso perineal e as medidas do canal anal. RESULTADOS: Dos 39 pacientes estudados, todos apresentaram alterações radiológicas, sendo a maioria do sexo feminino (95%). O mais novo tinha 18 anos e o mais velho, 82 anos (idade média de 52 ± 13 anos). Dez pacientes tinham menos de 40 anos, 18 tinham entre 40 e 60 anos e 11 pacientes tinham mais do que 60 anos. Os diagnósticos mais prevalentes foram retocele anterior (77%) e enterocele (38%). Os menos frequentes foram prolapso vaginal (2%), prolapso uterino (2%) e divertículo de Meckel (2%). CONCLUSÃO: As mulheres realizam mais exames de defecografia, porém ambos os gêneros se beneficiam deste estudo. A defecografia é capaz de detectar causas complexas de distúrbio da defecação como prolapso vaginal, uterino e retal, e pode ser utilizada em condições clínicas mais simples como a avaliação de retocele ou enterocele.

20.
Sci Rep ; 5: 17937, 2015 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-26658647

RESUMEN

Topological insulators form a novel state of matter that provides new opportunities to create unique quantum phenomena. While the materials used so far are based on semiconductors, recent theoretical studies predict that also strongly correlated systems can show non-trivial topological properties, thereby allowing even the emergence of surface phenomena that are not possible with topological band insulators. From a practical point of view, it is also expected that strong correlations will reduce the disturbing impact of defects or impurities, and at the same increase the Fermi velocities of the topological surface states. The challenge is now to discover such correlated materials. Here, using advanced x-ray spectroscopies in combination with band structure calculations, we infer that CeRu4Sn6 is a strongly correlated material with non-trivial topology.

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