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1.
Nature ; 563(7732): E29, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30237480

RESUMO

Four incorrect figure citations in this Letter have been corrected online.

2.
Nature ; 560(7719): 466-470, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30135529

RESUMO

The inversion of inhomogeneous physical states has great technological importance; for example, active noise reduction relies on the emission of an inverted sound wave that interferes destructively with the noise of the emitter1, and inverting the evolution of a spin system by using a magnetic-field pulse enables magnetic resonance tomography2. In contrast to these examples, inversion of a distribution of ferromagnetic or ferroelectric domains within a material is surprisingly difficult: field poling creates a single-domain state, and piece-by-piece inversion using a scanning tip is impractical. Here we report inversion of entire ferromagnetic and ferroelectric domain patterns in the magnetoelectric material Co3TeO6 and the multiferroic material Mn2GeO4, respectively. In these materials, an applied magnetic field reverses the magnetization or polarization, respectively, of each domain, but leaves the domain pattern intact. Landau theory indicates that this type of magnetoelectric inversion is universal across materials that exhibit complex ordering, with one order parameter holding the memory of the domain structure and another setting its overall sign. Domain-pattern inversion is only one example of a previously unnoticed effect in systems such as multiferroics, in which several order parameters are available for combination. Exploring these effects could therefore advance multiferroics towards new levels of functionality.

3.
Lupus ; 26(5): 510-516, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28394230

RESUMO

Objectives The objective of this study was to determine whether advanced MRI could provide biomarkers for diagnosis and prognosis in neuropsychiatric systemic lupus erythematosus (NPSLE). Methods Our prospective study included 28 systemic lupus erythematosus (SLE) patients with primary central NPSLE, 22 patients without NPSLE and 20 healthy controls. We used visual scales to evaluate atrophy and white matter hyperintensities, voxel-based morphometry and Freesurfer to measure brain volume, plus diffusion-tensor imaging (DTI) to assess white matter (WM) and gray matter (GM) damage. We compared the groups and correlated MRI abnormalities with clinical data. Results NPSLE patients had less GM and WM than controls ( p = 0.042) in the fronto-temporal regions and corpus callosum. They also had increased diffusivities in the temporal lobe WM ( p < 0.010) and reduced fractional anisotropy in the right frontal lobe WM ( p = 0.018). High clinical scores, longstanding disease, and low serum C3 were associated with atrophy, lower fractional anisotropy and higher diffusivity in the fronto-temporal lobes. Antimalarial treatment correlated negatively with atrophy in the frontal cortex and thalamus; it was also associated with lower diffusivity in the fronto-temporal WM clusters. Conclusions Atrophy and microstructural damage in fronto-temporal WM and GM in NPSLE correlate with severity, activity and the time from disease onset. Antimalarial treatment seems to give some brain-protective effects.


Assuntos
Substância Cinzenta/patologia , Lúpus Eritematoso Sistêmico/complicações , Vasculite Associada ao Lúpus do Sistema Nervoso Central/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Substância Branca/patologia , Adulto , Idoso , Corpo Caloso/diagnóstico por imagem , Corpo Caloso/patologia , Imagem de Tensor de Difusão/métodos , Feminino , Substância Cinzenta/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Substância Branca/diagnóstico por imagem , Adulto Jovem
4.
Biomed Opt Express ; 12(11): 7223-7243, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34858711

RESUMO

A microscope is an essential tool in biosciences and production quality laboratories for unveiling the secrets of microworlds. This paper describes the development of MicroHikari3D, an affordable DIY optical microscopy platform with automated sample positioning, autofocus and several illumination modalities to provide a high-quality flexible microscopy tool for labs with a short budget. This proposed optical microscope design aims to achieve high customization capabilities to allow whole 2D slide imaging and observation of 3D live specimens. The MicroHikari3D motion control system is based on the entry level 3D printer kit Tronxy X1 controlled from a server running in a Raspberry Pi 4. The server provides services to a client mobile app for video/image acquisition, processing, and a high level classification task by applying deep learning models.

5.
Infection ; 38(3): 227-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20405304

RESUMO

Seasonal influenza virus infection has been associated with a variety of neurologic complications. We report a case of novel influenza A (H1N1) encephalitis in an infant aged 3 months with an upper respiratory infection, who presented seizures. The infection was confirmed in nasopharyngeal aspirate and cerebrospinal fluid. Treatment with oseltamivir was started. He was discharged without any neurologic sequelae.


Assuntos
Encefalite Viral/virologia , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/virologia , Antivirais/uso terapêutico , Encefalite Viral/líquido cefalorraquidiano , Encefalite Viral/tratamento farmacológico , Humanos , Lactente , Vírus da Influenza A Subtipo H1N1/genética , Influenza Humana/líquido cefalorraquidiano , Influenza Humana/tratamento farmacológico , Masculino , Reação em Cadeia da Polimerase
6.
Semergen ; 45(8): 552-558, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-30954373

RESUMO

Scandinavian countries have one of the best health services, as well as quality of life, in all Europe. It is often unknown why this is the case, with the language barrier being one of the most frequent and difficult to overcome. A summary of the Danish health system is presented in order to know its main virtues and use its tools to eventually make improvements in our national health system. Many of them will not be able to be used due to the different management type, but some of them could be performed allowing us to improve and become better physicians. This presentation can be used as a reference for those who are training in Primary Care and who wish to do an external rotation in a Scandinavian country.


Assuntos
Atenção Primária à Saúde/organização & administração , Dinamarca , Humanos
7.
J Phys Condens Matter ; 29(3): 035701, 2017 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-27869646

RESUMO

The nature and symmetry of transition mechanisms in the spin-spiral copper halides CuCl2 and CuBr2 are analyzed theoretically. The magnetoelectric effects observed in the two multiferroic compounds are described and their phase diagram at zero and applied magnetic fields are worked out. The emergence of the electric polarization at zero field below the paramagnetic phase is shown to result from the coupling of two distinct spin-density waves and to be only partly related to the Dzialoshinskii-Moriya interactions. Applying a magnetic field along the two-fold monoclinic axis of CuCl2 yields a decoupling of the spin-density waves modifying the symmetry of the phase and the spin-spiral orientation. The remarkable periodic dependences of the magnetic susceptibility and polarization, on rotating the field in the monoclinic plane, are described theoretically.

8.
Phys Rev Lett ; 84(24): 5540-3, 2000 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-10990989

RESUMO

An analogy is stressed between the order-parameter symmetries of the two-dimensional d-pairing wave superconductors and of liquid-crystal mesophases formed from achiral bent-shaped molecules. It leads to a definition of a class of liquid-crystal states which are the analogs of the unconventional superconducting states, and are characterized by a loss of discrete symmetry operations of the parent state.

9.
Arthritis Care Res ; 6(1): 11-6, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8443252

RESUMO

This paper reports the results of a study of the gait of 102 patients with osteoarthritis of the knee. Functional status was measured by a 6-min test of walking distance; the stride characteristics associated with the walk test were assessed. Stride characteristics were measured by a Stride Analyzer. Patients were randomized to an 8-week educational and walking program (the intervention group) or to a weekly telephone survey (the control group). The intervention group patients had a 15% increase in walking distance (P < 0.0001) and increases of 9.1% in stride length at free walking speeds (P < 0.007) and 17% in stride length at fast walking speeds (P < 0.01) compared to the control group. The results of this study have shown that the walking and educational program was effective in improving gait function in patients with osteoarthritis of the knee.


Assuntos
Marcha , Osteoartrite/reabilitação , Caminhada , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Articulação do Joelho/fisiopatologia , Masculino , Pessoa de Meia-Idade , Osteoartrite/fisiopatologia , Dor/fisiopatologia
10.
SEMERGEN, Soc. Esp. Med. Rural Gen. (Ed. Impr.) ; 45(8): 552-558, nov.-dic. 2019. tab, graf
Artigo em Espanhol | IBECS (Espanha) | ID: ibc-189295

RESUMO

Los países escandinavos se encuentran situados entre los que tienen las mejores prestaciones de salud, así como calidad de vida, en toda Europa. Pero muchas veces desconocemos a qué se puede deber este efecto, siendo la barrera del idioma una de las más frecuentes y difíciles de sobrepasar. Pretendemos realizar un resumen del sistema sanitario danés para conocer sus principales virtudes y utilizando sus herramientas poder eventualmente llevar a cabo mejoras en nuestro sistema nacional de salud. Probablemente muchas no puedan ser realizadas por el diferente ámbito de gestión, pero algunas si podrían tener cabida, permitiéndonos mejorar más aún. Esta presentación puede además servir como una referencia a aquellos residentes de atención primaria que deseen hacer una rotación externa en un país escandinavo


Scandinavian countries have one of the best health services, as well as quality of life, in all Europe. It is often unknown why this is the case, with the language barrier being one of the most frequent and difficult to overcome. A summary of the Danish health system is presented in order to know its main virtues and use its tools to eventually make improvements in our national health system. Many of them will not be able to be used due to the different management type, but some of them could be performed allowing us to improve and become better physicians. This presentation can be used as a reference for those who are training in Primary Care and who wish to do an external rotation in a Scandinavian country


Assuntos
Humanos , Atenção Primária à Saúde/organização & administração , Dinamarca
11.
An Pediatr (Barc) ; 76(5): 285-9, 2012 May.
Artigo em Espanhol | MEDLINE | ID: mdl-22197738

RESUMO

Pulmonary sequestration is a rare malformation characterised by non-functioning lung tissue, separated from the tracheobronchial tree and with arterial supply from the systemic circulation. The classical therapeutic approach is surgical resection. In recent years, the endovascular embolisation technique is increasingly being used for the treatment of this disease. The embolisation materials used are coils and vascular plugs. The Amplatzer® vascular plug is a self-expandable cylindrical mesh device, particularly useful for the embolisation of large vessels with high flow. Three cases of pulmonary sequestration were treated by embolisation with Amplatzer® vascular plugs. In all cases the procedure was performed without complications, and the aortopulmonary collateral vessels were completely occluded. Our study provides new data on the safety and efficacy of pulmonary embolisation with Amplatzer® vascular plugs, and its preference over coils in the embolisation of large vessels.


Assuntos
Sequestro Broncopulmonar/cirurgia , Procedimentos Endovasculares , Dispositivo para Oclusão Septal , Criança , Feminino , Humanos , Lactente
12.
J Phys Condens Matter ; 22(6): 065901, 2010 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-21389374

RESUMO

The ferroelectric order and magnetic field induced effects observed in the spiral phase of MnWO4 are described theoretically. It is demonstrated explicitly that the Dzyaloshinskii-Moriya antisymmetric interactions contribute to the correlation between spins and electric dipoles in the incommensurate and commensurate ferroelectric phases of magnetic multiferroics. However, other single-site symmetric interactions are shown to be involved in the magnetoelectric process, suggesting the possible existence of an electric polarization originating from purely symmetric effects.

13.
Phys Rev Lett ; 71(4): 553-556, 1993 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-10055305
15.
Phys Rev Lett ; 77(11): 2284-2287, 1996 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-10061905
17.
Phys Rev Lett ; 62(7): 844, 1989 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-10040351
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