Search results for "spin"
showing 10 items of 5044 documents
Molecular Spintronic Devices: from Molecular Spin Valves to Spin-OLEDs
2017
La investigación llevada a cabo durante el periodo de tesis doctoral y que se describe en este manuscrito pertenece al campo de la espintrónica molecular. Ha sido motivada por el deseo de incorporar nuevos materiales moleculares a dispositivos espintrónicos y ahondar en la comprensión de la inyección y el transporte de espín en este tipo de capas, a través del estudio de dispositivos como la válvula de espín molecular y el spin-OLED. En 1988 Albert Fert y Peter Grünberg descubrieron que la resistencia eléctrica de unas multicapas de Fe-Cr variaba considerablemente en función de la magnetización de las láminas. El efecto se conoce hoy en día como magnetoresistencia gigante o GMR, por sus sig…
Molecular nanostructures on ferromagnetic metals for spintronics
2017
El objetivo principal de esta tesis ha sido el estudio de la funcionalización de superficies ferromagnéticas mediante la formación de monocapas moleculares autoensambladas, (SAMs, self-assembled monolayers) con el fin de conseguir procesos sencillos y fiables para la preparación de interfaces híbridas aplicables en dispositivos de espintrónica molecular. La investigación se ha centrado en la funcionalización de materiales ferromagnéticos, concretamente el cobalto y la aleación de níquel:hierro conocida como Permalloy. Las propiedades magnéticas y de polarización de espín de estos metales ferromagnéticos se mantienen a temperatura ambiente, lo que los hace muy interesantes para su aplicación…
Spin crossover cobalt(II) molecular nanomagnets as dynamic molecular systems
2022
Los complejos mononucleares de iones metálicos paramagnéticos de la primera serie de transición con ligandos "no-inocentes" hechos a medida han surgido recientemente como prototípicos de sistemas moleculares dinámicos (DMSs, del inglés “dynamic molecular systems”). El enorme impacto de los DMSs en varios dominios de la nanociencia y nanotecnología molecular se debe a su capacidad para ejecutar funciones específicas y selectivas bajo el control de un estímulo externo que modula adecuadamente sus propiedades estructurales y electrónicas (ópticas, redox y magnéticas). En esta Tesis Doctoral, a lo largo de siete capítulos describimos la química y las propiedades físicas de una clase única de na…
Reliability of transcranial magnetic stimulation and H-reflex measurement during balance perturbation tasks
2022
Following ankle movement, posterior balance perturbation evokes short- (SLR ∼30–50 ms), medium- (MLR ∼50–60 ms), and long-latency responses (LLR ∼70–90 ms) in soleus muscle before voluntary muscle contraction. Transcranial magnetic stimulation (TMS) and Hoffmann-reflex (H-reflex) measurements can provide insight into the contributions of corticospinal and spinal mechanisms to each response. Motor evoked potential (MEP) and H-reflex responses have shown good reliability in some dynamic muscle contraction tasks. However, it is still unclear how reliable these methods are in dynamic balance perturbation and corticospinal modulation during long amplitude balance perturbation tasks. 14 subjects …
Proprioceptive response strength in the primary sensorimotor cortex is invariant to the range of finger movement
2023
Available online 13 February 2023 Proprioception is the sense of body position and movement that relies on afference from the proprioceptors in muscles and joints. Proprioceptive responses in the primary sensorimotor (SM1) cortex can be elicited by stim- ulating the proprioceptors using evoked (passive) limb movements. In magnetoencephalography (MEG), propri- oceptive processing can be quantified by recording the movement evoked fields (MEFs) and movement-induced beta power modulations or by computing corticokinematic coherence (CKC) between the limb kinematics and cortical activity. We examined whether cortical proprioceptive processing quantified with MEF peak strength, relative beta supp…
Extracellular vesicles isolated by cerebrospinal fluid as biomarkers of inflammation in multiple sclerosis and inflammatory neurological diseases.
2014
NMR and μ+SR detection of unconventional spin dynamics in Er(trensal) and Dy(trensal) molecular magnets
2019
POSTURE AND POSTUROLOGY, ANATOMICAL AND PHYSIOLOGICAL PROFILES: OVERVIEW AND CURRENT STATE OF ART
2017
Background and aim of work: posture is the position of the body in the space, and is controlled by a set of anatomical structures. The maintenance and the control of posture are a set of interactions between muscle-skeletal, visual, vestibular, and skin system. Lately there are numerous studies that correlate the muscle-skeletal and the maintenance of posture. In particular, the correction of defects and obstruction of temporomandibular disorders, seem to have an impoact on posture. The aim of this work is to collect information in literature on posture and the influence of the stomatognatich system on postural system. Methods: Comparison of the literature on posture and posturology by cons…
Sexual dimorphism in the vertebral wedging of the human lumbar vertebrae and its importance as a comparative framework for understanding the wedging …
2020
Lumbar lordosis is a key element of the upright posture, being interpreted as a consequence of bipedal locomotion. There is consensus that the generic modern human pattern of metameric vertebral body wedging is sexually dimorphic in modern humans. However, recently published studies have compared this pattern with other hominins, such as Neanderthals. These tried to establish whether the (male) Neanderthal lumbar vertebrae express a pattern that falls within or outside the range of modern human males. In the present study, data collected by 3D landmarks of the lumbar vertebrae of modern humans from different geographic regions and Neanderthals (Ntotal = 505 individual vertebrae) are used to…
The assessment of skeletal status in young patients with Turner syndrome by 2 densitometric techniques: Phalangeal quantitative ultrasound and dual e…
2018
Background. Studies using dual energy X-ray absorptiometry (DXA) demonstrate a reduction in bone mineral density (BMD) in children and adolescents with Turner syndrome (TS). However, these studies do not take into account changes in bone size, which influence BMD in the case of short-statured patients. Phalangeal quantitative ultrasound (phQUS) measurements have shown an ability to reveal changes due to skeletal growth, aging, and bone and mineral disorders. There is limited data on bone mineral status in girls with TS assessed by 2 different techniques, i.e., DXA and phQUS. Objectives. The aim of this study was to investigate the potential negative impact of TS on bone status and to assess…