Neurosurgery and brain shift: review of the state of the art and main contributions of robotics

Este artículo presenta una revisión acerca de la neurocirugía, los asistentes robóticos en este tipo de procedimiento, y el tratamiento que se le da al problema del desplazamiento que sufre el tejido cerebral, incluyendo las técnicas para la obtención de imágenes médicas. Se abarca de manera especial el fenómeno del desplazamiento cerebral, comúnmente conocido como brain shift, el cual causa pérdida de referencia entre las imágenes preoperatorias y los volúmenes a tratar durante la cirugía guiada por imágenes médicas. Hipotéticamente, con la predicción y corrección del brain shift sobre el sistema de neuronavegación, se podrían planear y seguir trayectorias de mínima invasión, lo que conllevaría a minimizar el daño a los tejidos funcionales y posiblemente a reducir la morbilidad y mortalidad en estos delicados y exigentes procedimientos médicos, como por ejemplo, en la extirpación de un tumor cerebral. Se mencionan también otros inconvenientes asociados a la neurocirugía y se muestra cómo los sistemas robotizados han ayudado a solventar esta problemática. Finalmente se ponen en relieve las perspectivas futuras de esta rama de la medicina, la cual desde muchas disciplinas busca tratar las dolencias del principal órgano del ser humano.This paper presents a review about neurosurgery, robotic assistants in this type of procedure, and the approach to the problem of brain tissue displacement, including techniques for obtaining medical images. It is especially focused on the phenomenon of brain displacement, commonly known as brain shift, which causes a loss of reference between the preoperative images and the volumes to be treated during image-guided surgery. Hypothetically, with brain shift prediction and correction for the neuronavigation system, minimal invasion trajectories could be planned and shortened. This would reduce damage to functional tissues and possibly lower the morbidity and mortality in delicate and demanding medical procedures such as the removal of a brain tumor. This paper also mentions other issues associated with neurosurgery and shows the way robotized systems have helped solve these problems. Finally, it highlights the future perspectives of neurosurgery, a branch of medicine that seeks to treat the ailments of the main organ of the human body from the perspective of many disciplines

On the Selectivity of Planar Microwave Glucose Sensors with Multicomponent Solutions

The development of glucose concentration sensors by means of microwave planar resonant technology is an active field attracting considerable attention from the scientific community. Although showing promising results, the current experimental sensors are facing some fundamental challenges. Among them, the most critical one seems to be the selectivity of glucose concentration against the variations of the concentrations of other components or parameters. In this article, we investigate the selectivity of microwave planar resonant sensors when measuring multicomponent solutions. Three sensors are involved, two of them having been designed looking for a more simplified system with a reduced size, and the third one has been specially developed to improve the sensitivity. The performance of these sensors is thoroughly assessed with a large set of measurements involving multicomponent solutions composed of pure water, NaCl, albumin at different concentrations and glucose at different concentrations. The impact of the simultaneous variations of the concentrations of glucose and albumin on the final measurements is analyzed, and the effective selectivity of the sensors is discussed. The results show a clear influence of the albumin concentration on the measurements of the glucose concentration, thereby pointing to a lack of selectivity for all sensors. This influence has been modeled, and strategies to manage this selectivity challenge are inferredThis research was partially funded by AEI (Spanish Research State Agency) through the Race project (reference PID2019-111023RB-C32). The work of C.G.J. was funded by the Ministry of Universities in the Government of Spain, the European Union–NextGenerationEU and the Miguel Hernández University of Elche through the Margarita Salas postdoctoral program, and also by Conselleria d’Innovació, Universitats, Ciència i Societat Digital in Generalitat Valenciana (Government of Valencia Region) and European Social Fund through the APOSTD postdoctoral program, grant number CIAPOS/2021/267. Partial funding for open access charge: Universidad de Málaga

Relaxation in non-Markovian models: From static to dynamic heterogeneity

[EN] Glass transition processes have often been explained in terms of wide distributions of relaxation times. By means of a simple stochastic model we here show how dynamic heterogeneity is the key to the emergence of the glass transition. A non-Markovian model representing a small open region of the amorphous material was previously shown to reproduce the time and thermal characteristic behavior of supercooled liquids and glasses. Due to the interaction of the open regions with their environment, the temperature dependence of the equilibrium relaxation times differs from the featureless behavior of the relaxation times of closed regions, whose static disorder does not lead to a glass transition, even with wider distributions of equilibrium relaxation times. The dynamic heterogeneity of the open region produces a glass transition between two different regimes: a faster-thanArrhenius and non-diverging growth of the supercooled liquid relaxation times and an average Arrhenius behavior of the ideal glass. The Kovacs' expansion gap was studied by evaluating the nonequilibrium distribution of relaxation times after the temperature quenches.Funding for open access charge: CRUE-Universitat Polit`ecnica de Val`encia. RSS and JMM acknowledge the Spanish Ministry of Science, Innovations and Universities through the RTI2018-097862-B-C21 Project (including the FEDER financial support). CIBER-BBN is an initiative funded by the VI National R&D&I Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program. CIBER Actions are financed by the Instituto de Salud Carlos III with assistance from the European Regional Development Fund.Torregrosa Cabanilles, C.; Molina Mateo, J.; Sabater I Serra, R.; Meseguer Dueñas, JM.; Gómez Ribelles, JL. (2022). Relaxation in non-Markovian models: From static to dynamic heterogeneity. Journal of Non-Crystalline Solids. 576. https://doi.org/10.1016/j.jnoncrysol.2021.12124512124557

Plataforma basada en la integración de MATLAB® y ROS para la docencia de robótica de servicio

[Resumen] En este artículo se presenta una propuesta docente basada en una plataforma compuesta por Matlab® y ROS desarrollada en la asignatura “Robótica de Servicio” en la titulación de MásterUniversitario en Ingeniería Industrial de la Universidad Miguelpráctico en el que se introduce al alumno en el interacción con los sistemas sensoriales del robot y sus actuadores. La componente innovadora se encuentra en el uso de una herramienta previamente conocida por el alumno (Matlab®) integrada con una plataforma más compleja y realista (ROS) para poder ofrecer la formación práctica adecuada con los recursos habituales.Ministerio de Economía y Competitividad; DPI2013-47196-C3-

Buccodental health and oral mucositis : clinical study in patients with hematological diseases

El objetivo del presente trabajo fue valorar si un buen estado buco-dental (valorado mediante índices dento-gingivales), se asociaba a una menor incidencia y gravedad de mucositis oral en pacientes con enfermedades hematológicas que iban a recibir tratamiento con quimioterapia o un trasplante de médula ósea. Diseño del estudio: El estudio se llevó a cabo en 97 pacientes ingresados en el Servicio de Hematología del Hospital Duran y Reynals en Barcelona en los años 2002-2003. Estos pacientes recibían tratamiento con quimioterapia o bien el acondicionamiento previo a un trasplante de médula ósea. Se realizó un estudio descriptivo analizando un índice dental, dos índices gingivales y la higiene oral y su relación con la aparición de mucositis. Resultados: Los pacientes que durante la quimioterapia mostraron valores elevados del índice de placa (IP) y gingival (IG) presentaron un mayor porcentaje de mucositis (77.4% y 65.7% respectivamente) frente a los que tenían poca placa o ésta no era visible. En el caso del IP las diferentas fueron estadísticamente significativas (p=0.015). Asimismo los pacientes que cepillaban los dientes 3veces/día sólo presentaron mucositis en un 26.7% de los casos, frente a los que no cepillaban o lo hacían una vez al día (65.9% y 68.4%), siendo estas diferencias también estadísticamente significativas (p=0.013). El ICAO mostró resultados similares en los pacientes con o sin mucositis (7.59 y 7.03 respectivamente). Conclusiones: En nuestro trabajo, un buen estado gingival así como una buena higiene oral durante la quimiorradioterapia, se asocian a una menor incidencia y gravedad de mucositis

Dynamic bonding influenced by the proximity of adatoms to one atom high step edges

Low-temperature scanning tunneling microscopy is used here to study the dynamic bonding of gold atoms on surfaces under low coordination conditions. In the experiments, using an atomically sharp gold tip, a gold adatom is deposited onto a gold surface with atomic precision either on the first hollow site near a step edge or far away from it. Classical molecular dynamics simulations at 4.2 K and density-functional theory calculations serve to elucidate the difference in the bonding behavior between these two different placements, while also providing information on the crystalline classification of the STM tips based on their experimental performanc

Dynamic Adaptive System for Robot-Assisted Motion Rehabilitation

This paper presents a dynamic adaptive system for administration of robot-assisted therapy. The main novelty of the proposed approach is to close patient in the loop and use multisensory data (such as motion, forces, voice, muscle activity, heart rate, and skin conductance) to adaptively and dynamically change the complexity of the therapy and real-time displays of an immersive virtual reality system in accordance with specific patient requirements. The proposed rehabilitation system can be considered as a complex system that is composed of the following subsystems: data acquisition, multimodal human–machine interface, and adaptable control system. This paper shows the description of the developed fuzzy controller used as the core of the adaptable control subsystem. Finally, experimental results with ten subjects are reported to show the performance of the proposed solution

Análisis del espacio de trabajo de un robot paralelo de 3RRR

Comunicación presentada en las XXIX Jornadas de Automática, Tarragona, 3-5 Septiembre 2008.El objetivo de este artículo es realizar el análisis del espacio de trabajo de un robot paralelo esférico del tipo 3RRR mediante una herramienta matemática desarrollada en Matlab. Este 3RRR contiene una particularidad que lo diferencia con respecto a los robots esféricos comunes debido a las exigencias de su aplicación: su centro de rotación no se encuentra en el centro del robot. Basándonos en un parámetro que define la habilidad o destreza del robot (dexterity), calcularemos el valor de las variables que optimizan su espacio de trabajo

Qüestionaris d’autoavaluació a través del campus digital: una eina d’aprenentatge.

Amb l’objectiu de validar els qüestionaris d’autoavaluació com a eina d’aprenentatge s’ha incorporat aquesta activitat a un total de 10 assignatures diferents de matemàtiques de l’EUETIT i de l’EUOOT durant els dos quadrimestres del curs 2006/2007 mitjançant Atenea, l’entorn virtual d’aprenentatge basat en Moodle de la UPC. Els paràmetres de configuració dels qüestionaris d’autoavaluació de Moodle han permès planificar i organitzar aquesta activitat responent a l’especificitat de cada assignatura i als usos que se’ls hi volien donar (més orientats a teoria i problemes o a pràctiques) determinant també els valors més adequats de freqüència, dimensió, caràcter obligatori o voluntari, pes en la qualificació global i entorn en què els estudiants responien els qüestionaris. El seguiment d’aquesta activitat ha estat molt alta, fins i tot en els casos que no era obligatòria. Al final de cada quadrimestre s’ha enquestat els estudiants matriculats en aquestes assignatures, un total de 507. Amb una participació mitjana lleugerament superior al 73%, valoren de forma notablement positiva la incorporació de qüestionaris d’autoavaluació a les assignatures i manifesten clarament que els resulta profitosa en el seu procés d’aprenentatge en tots els casos, siguin quines siguin les característiques de planificació i organització de l’activitat

Dynamic bonding of metallic nanocontacts: Insights from experiments and atomistic simulations

The conductance across an atomically narrow metallic contact can be measured by using scanning tunneling microscopy. In certain situations, a jump in the conductance is observed right at the point of contact between the tip and the surface, which is known as “jump to contact” (JC). Such behavior provides a way to explore, at a fundamental level, how bonding between metallic atoms occurs dynamically. This phenomenon depends not only on the type of metal but also on the geometry of the two electrodes. For example, while some authors always find JC when approaching two atomically sharp tips of Cu, others find that a smooth transition occurs when approaching a Cu tip to an adatom on a flat surface of Cu. In an attempt to show that all these results are consistent, we make use of atomistic simulations; in particular, classical molecular dynamics together with density functional theory transport calculations to explore a number of possible scenarios. Simulations are performed for two different materials: Cu and Au in a [100] crystal orientation and at a temperature of 4.2 K. These simulations allow us to study the contribution of short- and long-range interactions to the process of bonding between metallic atoms, as well as to compare directly with experimental measurements of conductance, giving a plausible explanation for the different experimental observations. Moreover, we show a correlation between the cohesive energy of the metal, its Young's modulus, and the frequency of occurrence of a jump to contact.W. Dednam acknowledges support from the National Research Foundation of South Africa through the Scarce Skills Masters scholarship funding programme (Grant Unique Number 92138). This work is supported by the Generalitat Valenciana through Grant Reference PROMETEO2012/011 and MINECO under Grant No. FIS2013-47328, by European Union structural funds and the Comunidad de Madrid Programs S2013/MIT-3007 and P2013/MIT-2850. This work is also part of the research programme of the Foundation for Fundamental Research on Matter (FOM), which is financially supported by the Netherlands Organisation for Scientific Research (NWO)