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1.
ACS Appl Mater Interfaces ; 11(3): 3214-3223, 2019 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-30588788

RESUMEN

We report on the simplest magnetic nanowire-based surface walker that is able to change its propulsion mechanism near a surface boundary as a function of the applied rotating magnetic field frequency. The nanowires are made of CoPt alloy with semihard magnetic properties synthesized by means of template-assisted galvanostatic electrodeposition. The semihard magnetic behavior of the nanowires allows for programming their alignment with an applied magnetic field as they can retain their magnetization direction after premagnetizing them. By engineering the macroscopic magnetization, the nanowires' speed and locomotion mechanism are set to tumbling, precession, or rolling depending on the frequency of an applied rotating magnetic field. Also, we present a mathematical analysis that predicts the translational speed of the nanowire near the surface, showing a very good agreement with experimental results. Interestingly, the maximal speed is obtained at an optimal frequency (∼10 Hz), which is far below the theoretical step-out frequency (∼345 Hz). Finally, vortices are found by tracking polystyrene microbeads, trapped around the CoPt nanowire, when they are propelled by precession and rolling motion.

2.
Injury ; 48 Suppl 6: S91-S95, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29162249

RESUMEN

BACKGROUND: Displaced intra-articular calcaneal fractures (DIACFs) can have long-term consequences in terms of foot pain and disability. This injury frequently occurs in the context of polytrauma patients and its influence in long-term functional prognosis is well known. The purpose of this study is to compare the etiology, severity, and functional outcome of the operated DIACFs between polytrauma patients and isolated cases. METHODS: Eighty-six patients with operated displaced intra-articular calcaneal fractures through open reduction and internal fixation (ORIF) were managed at our institution between January 1, 2008 and December 31, 2015. Eighty patients completed the follow-up, nine of them with both calcaneus operated (89 calcaneus) by ORIF with a plate. Two groups were established; one included 11 (14%) polytrauma patients, three of them with operated bilateral calcaneus, and 69 (86%) patients without polytrauma diagnosis. Severity of trauma, injury patterns, psychiatric background, associated fractures, second surgeries and functional questionnaire (adjusted American Orthopedic Foot and Ankle Society - AOFAS - ankle-hindfoot scale and SF-36) were collected. A detailed comparative statistical analysis is provided. RESULTS: There was significant statistical relationship between polytrauma patients and those with psychiatric comorbidities, severe trauma or severe injury, but not with second surgeries, later subtalar arthrodesis or outcome measures. Only calcaneal fractures with comminution according to Sanders classification was associated with second surgeries and later subtalar arthrodesis. The AOFAS score was solely related to trauma severity (71.5 vs 77; p = 0.29) and calcaneal fracture's comminution according to Sanders classification (79.4 type II and 79.3 type III vs 69.2 type IV; p = 0.000 and p = 0.008, respectively) and SF-36 score only with trauma severity (67.4 vs 78.1; p = 0.00) and psychiatric comorbidities (62.2 vs 75.8; p = 0.048). CONCLUSION: No differences in outcome measures and second surgeries were found between polytrauma patients and isolated fractures. For DIACFs, the severity of the impact was correlated with a higher number of second surgeries and worse functional outcomes. Following a DIACF, patients with psychiatric comorbidities presented worse health-related quality of life than people without this background.


Asunto(s)
Calcáneo/lesiones , Traumatismos de los Pies/fisiopatología , Fijación Interna de Fracturas , Fracturas Óseas/fisiopatología , Fracturas Óseas/rehabilitación , Reducción Abierta , Recuperación de la Función/fisiología , Adolescente , Adulto , Anciano , Calcáneo/fisiopatología , Calcáneo/cirugía , Comorbilidad , Femenino , Estudios de Seguimiento , Traumatismos de los Pies/rehabilitación , Traumatismos de los Pies/cirugía , Fracturas Óseas/cirugía , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Traumatismo Múltiple , Calidad de Vida , Estudios Retrospectivos , Índices de Gravedad del Trauma , Resultado del Tratamiento , Adulto Joven
3.
ACS Appl Mater Interfaces ; 9(18): 15577-15582, 2017 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-28429588

RESUMEN

Steady or dynamic magnetoelectric response, selectable and adjustable by only varying the amplitude of the applied electric field, is found in a multiferroic FeRh/PMN-PT device. In-operando time-dependent structural, ferroelectric, and magnetoelectric characterizations provide evidence that, as in magnetic shape memory martensitic alloys, the observed distinctive magnetoelectric responses are related to the time-dependent relative abundance of antiferromagnetic-ferromagnetic phases in FeRh, unbalanced by voltage-controlled strain. This flexible magnetoelectric response can be exploited not only for energy-efficient memory operations but also in other applications, where multilevel and/or transient responses are required.

4.
Phys Rev B ; 94(5)2016 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-28459114

RESUMEN

The evolution of local ferroelectric lattice distortions in multiferroic Ge1-x Mn x Te is studied by x-ray diffraction, x-ray absorption spectroscopy and density functional theory. We show that the anion/cation displacements smoothly decrease with increasing Mn content, thereby reducing the ferroelectric transition from 700 to 100 K at x = 0.5, where the ferromagnetic Curie temperature reaches its maximum. First principles calculations explain this quenching by different local bond contributions of the Mn 3d shell compared to the Ge 4s shell in excellent quantitative agreement with the experiments.

5.
Sci Rep ; 5: 14367, 2015 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-26403693

RESUMEN

Silicon has persevered as the primary substrate of microelectronics during last decades. During last years, it has been gradually embracing the integration of ferroelectricity and ferromagnetism. The successful incorporation of these two functionalities to silicon has delivered the desired non-volatility via charge-effects and giant magneto-resistance. On the other hand, there has been a numerous demonstrations of the so-called magnetoelectric effect (coupling between ferroelectric and ferromagnetic order) using nearly-perfect heterostructures. However, the scrutiny of the ingredients that lead to magnetoelectric coupling, namely magnetic moment and a conducting channel, does not necessarily require structural perfection. In this work, we circumvent the stringent requirements for epilayers while preserving the magnetoelectric functionality in a silicon-integrated device. Additionally, we have identified an in-plane tunnelling mechanism which responds to a vertical electric field. This genuine electroresistance effect is distinct from known resistive-switching or tunnel electro resistance.

6.
Nano Lett ; 15(4): 2229-34, 2015 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-25734797

RESUMEN

We report a voltage controlled reversible creation and annihilation of a-axis oriented ∼10 nm wide ferroelastic nanodomains without a concurrent ferroelectric 180° switching of the surrounding c-domain matrix in archetypal ferroelectric Pb(Zr0.2Ti0.8)O3 thin films by using the piezo-response force microscopy technique. In previous studies, the coupled nature of ferroelectric switching and ferroelastic rotation has made it difficult to differentiate the underlying physics of ferroelastic domain wall movement. Our observation of distinct thresholds for ferroelectric and ferroelastic switching allows us investigate the ferroelastic switching cleanly and demonstrate a new degree of nanoscale control over the ferroelastic domains.

7.
ACS Nano ; 7(11): 10397-404, 2013 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-24156282

RESUMEN

Demand for visualizing nanoscale dynamics in biological and advanced materials continues to drive the development of subdiffraction optical probes. While many strategies employ scanning tips for this purpose, we instead exploit a focused electron beam to create scannable nanoscale optical excitations in an epitaxially grown thin-film of cerium-doped yttrium aluminum perovskite, whose cathodoluminescence response is bright, robust, and spatially resolved to 18 nm. We also demonstrate lithographic patterning of the film's luminescence at the nanoscale. We anticipate that converting these films into free-standing membranes will yield a powerful near-field optical microscopy without the complication of mechanical scanning.


Asunto(s)
Electrodos , Luminiscencia , Óptica y Fotónica/métodos , Aluminio/química , Cerio/química , Electrones , Diseño de Equipo , Rayos Láser , Ensayo de Materiales , Método de Montecarlo , Nanopartículas/química , Nanoestructuras/química , Nanotecnología/métodos , Propiedades de Superficie
8.
Rev. esp. med. legal ; 39(1): 7-11, ene.-mar. 2013.
Artículo en Español | IBECS | ID: ibc-109061

RESUMEN

Introducción. La violencia de género es un problema de salud pública en el que el médico forense ocupa un papel protagonista. El objetivo del estudio fue ampliar el conocimiento existente acerca de las características de la violencia de género en L’Hospitalet de Llobregat, para favorecer la identificación de los grupos de riesgo y la posible incorporación de medidas protectoras necesarias hacia los colectivos más vulnerables. Material y métodos. Estudio prospectivo de víctimas y agresores evaluados entre el 01.01.2009 y el 30.09.2009 en L’Hospitalet de Llobregat. Resultados. La muestra incluyó 404 casos en este periodo: el 80,7% fueron mujeres, la franja de edad se encontraba entre 20 y 40 años en el 69% de los casos y eran de nacionalidad española en el 30,2%. El alcohol y los celos estaban presentes en el 39 y el 29% de los casos respectivamente, registrándose el 47,5% de los casos durante el fin de semana. La contusión fue el mecanismo lesivo hallado en el 94,7% de los casos, siendo las extremidades superiores la zona corporal más frecuententemente lesionada. El 94% requirieron una primera asistencia facultativa desde el punto de vista médico-legal. Los primeros años de la relación aglutinan la mayoría de episodios de violencia. Discusión y conclusiones. El mayor conocimiento de las características de la violencia de género y los perfiles de víctima y agresor puede repercutir en una mejora en la calidad pericial(AU)


Introduction. Gender-based violence is a public health problem where the forensic doctor plays a key role. Material and methods. Prospective study of victims and offenders between 01-01-09 and 09-30-09 in L’Hospitalet de Llobregat was conducted. The aim of study is, on the one hand, to broaden the knowledge about the characteristics of gender violence in L’Hospitalet de Llobregat in order to favor the identification of risk groups; on the other hand, the possible incorporation of necessary protective measures for the most vulnerable groups. Results. The sample included 404 cases in this period: 80.7% of women that were between the ages of 20 and 40 in 69% of the cases; 30.2% of them being from Spain. Alcohol and jealousy were present in 39 and 29% of the cases respectively, and 47.5% occurred during the weekend. The main injury mechanism was bruising, affecting 94.7% of cases, where upper extremities were the most frequently injured parts of the body. First medical aid was required in 94% of the cases. The early years of the relationship are shown to be the ones where most of the violence occurred. Discussion and conclusions. A greater knowledge of the characteristics of gender-based violence and victim and offender profiles can help to improve the quality of expert reports(AU)


Asunto(s)
Humanos , Femenino , Adulto , Violencia contra la Mujer , Maltrato Conyugal/legislación & jurisprudencia , Maltrato Conyugal/prevención & control , Maltrato Conyugal/psicología , Agresión/fisiología , Salud Pública/legislación & jurisprudencia , Salud Pública/métodos , Estudios Prospectivos , 28599
9.
Ann Vasc Surg ; 26(8): 1071-6, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22835567

RESUMEN

BACKGROUND: To assess the role of ultrasound arterial mapping in planning therapeutic options for critical limb ischemia (CLI) in diabetic patients. METHODS: This observational and comparative study included 244 patients with CLI. All participants (64% were diabetic) underwent ultrasound arterial mapping before planning surgical treatment. We established two groups: diabetic (n = 156) and nondiabetic (n = 88). Arterial mapping was divided into segments. We studied 2,021 individual segments and used arteriography when ultrasound arterial mapping was not conclusive. We compared the degree of pathology between the groups, agreement between the treatment decision made after ultrasound mapping and the final surgical decision in both groups, and agreement between ultrasound mapping and arteriography in patients who underwent both procedures. RESULTS: Diabetic patients had a significantly higher degree of pathology in all segments, except the common iliac artery. Decisions made after ultrasound mapping matched the final surgical decision 90% and 94% of the time in diabetic patients and nondiabetic patients, respectively. Decisions made on the basis of ultrasound arterial mapping matched decisions made on the basis of arteriography in 86.3%. CONCLUSIONS: Ultrasound arterial mapping allowed for good therapeutic planning for CLI in diabetic patients, even though these patients had more severe arterial pathology.


Asunto(s)
Angiopatías Diabéticas/diagnóstico por imagen , Angiopatías Diabéticas/cirugía , Isquemia/diagnóstico por imagen , Isquemia/cirugía , Extremidad Inferior/irrigación sanguínea , Cirugía Asistida por Computador , Ultrasonografía Doppler de Pulso , Procedimientos Quirúrgicos Vasculares , Adulto , Anciano , Anciano de 80 o más Años , Distribución de Chi-Cuadrado , Enfermedad Crítica , Técnicas de Apoyo para la Decisión , Femenino , Humanos , Masculino , Persona de Mediana Edad , Selección de Paciente , Valor Predictivo de las Pruebas , Radiografía , Índice de Severidad de la Enfermedad
10.
Arch Ital Biol ; 150(1): 22-30, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22786835

RESUMEN

The effects of different temperature-acclimations on cellular proliferation and migration were studied in the cerebral cortex of the tropical lizard, Tropidurus hispidus. Lizards were divided in two groups: warm-acclimated lizards (WALs), maintained at the temperature and photoperiod conditions of their natural habitat (mean temperature 26°C; 12:12 light:dark) and the cold-acclimated lizards (CALs), maintained at the same cycle of illumination and a mean temperature of 16°C. Animals were injected with the proliferative marker 5-bromodeoxyuridine (BrdU) and euthanized fifteen or thirty days later for the immunostaining. There was no difference in the number of BrdU-positive nuclei between the experimental groups in any of the cortical layers. In CALs, the positive nuclei were found mostly close to the ependyma, whereas in WALs many positive nuclei were also found in the plexiform and cellular layers of the cortex. In CALs, BrdU-positive nuclei appeared grouped (of 2-3 nuclei), a characteristic not seen in the other group. These data suggest that temperature affects the migrating capability of the newly generated neurons in the lizard cortex, but appears not to interfere with its generation.


Asunto(s)
Adaptación Fisiológica/fisiología , Movimiento Celular/fisiología , Corteza Cerebral/citología , Frío/efectos adversos , Animales , Bromodesoxiuridina/metabolismo , Proliferación Celular , Corteza Cerebral/metabolismo , Proteínas de Dominio Doblecortina , Femenino , Proteína Ácida Fibrilar de la Glía/metabolismo , Lagartos/anatomía & histología , Lagartos/fisiología , Masculino , Proteínas Asociadas a Microtúbulos/metabolismo , Neuropéptidos/metabolismo , Fotoperiodo
13.
Chem Commun (Camb) ; (7): 774-5, 2004 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-15045057

RESUMEN

A new family of differential chromogenic anion chemosensors is described based on anilinopyridine-metal cation coordinative signalling ensembles.

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