3,804 research outputs found
Modelling actin polymerization: the effect on confined cell migration
The aim of this work is to model cell motility under conditions of mechanical confinement. This cell migration mode may occur in extravasation of tumour and neutrophil-like cells. Cell migration is the result of the complex action of different forces exerted by the interplay between myosin contractility forces and actin processes. Here, we propose and implement a finite element model of the confined migration of a single cell. In this model, we consider the effects of actin and myosin in cell motility. Both filament and globular actin are modelled. We model the cell considering cytoplasm and nucleus with different mechanical properties. The migration speed in the simulation is around 0.1 µm/min, which is in agreement with existing literature. From our simulation, we observe that the nucleus size has an important role in cell migration inside the channel. In the simulation the cell moves further when the nucleus is smaller. However, this speed is less sensitive to nucleus stiffness. The results show that the cell displacement is lower when the nucleus is stiffer. The degree of adhesion between the channel walls and the cell is also very important in confined migration. We observe an increment of cell velocity when the friction coefficient is higher
Espacios artísticos para vivir las ciencias en Educación Infantil
Este trabajo presenta el diseño, planificación, implementación en el aula y análisis de una secuencia de ocho sesiones de instalación artística que posibilitan el aprendizaje de contenidos científicos en el alumnado de Educación Infantil (EI). Se analiza desde una perspectiva descriptiva cómo las actividades les permiten experimentar con los objetos que configuran cada instalación para descubrir los procesos científicos que implican sus acciones, verbalizarlos, pensar en lo que ocurre y conocer de este modo la ciencia que hay a nuestro alrededor.
This article presents the design, planning, classroom implementation and analysis of a sequence of eight artistic installation sessions that make it possible for early-childhood pupils to learn scientific content. Using a descriptive perspective, the study analyses how the activities allow researchers to experiment with each installation's object to discover the scientific processes involved in their actions, verbalise them, think about what is happening and thus know the science around us
Assessing potential interventions to maximize fisheries water productivity in the Eastern Gangetic Basin (EGB): Evaluation of constraints and opportunities for improvement context Gorai-Madhumati (GM) sub-basin
Growth and texture of Spark Plasma Sintered Al2O3 ceramics: a combined analysis of X-rays and Electron Back Scatter Diffraction
Textured alumina ceramics were obtained by Spark Plasma Sintering (SPS) of
undoped commercial a-Al2O3 powders. Various parameters (density, grain growth,
grain size distribution) of the alumina ceramics, sintered at two typical
temperatures 1400{\deg}C and 1700{\deg}C, are investigated. Quantitative
textural and structural analysis, carried out using a combination of Electron
Back Scattering Diffraction (EBSD) and X-ray diffraction (XRD), are represented
in the form of mapping, and pole figures. The mechanical properties of these
textured alumina ceramics include high elastic modulus and hardness value with
high anisotropic nature, opening the door for a large range of applicationsComment: 16 pages, 6 figures, submitted to J. Appl. Phy
Traumatic brain injury leads to alterations in contusional cortical miRNAs involved in dementia
There is compelling evidence that head injury is a significant environmental risk factor for Alzheimer's disease (AD) and that a history of traumatic brain injury (TBI) accelerates the onset of AD. Amyloid-β plaques and tau aggregates have been observed in the post-mortem brains of TBI patients; however, the mechanisms leading to AD neuropathology in TBI are still unknown. In this study, we hypothesized that focal TBI induces changes in miRNA expression in and around affected areas, resulting in the altered expression of genes involved in neurodegeneration and AD pathology. For this purpose, we performed a miRNA array in extracts from rats subjected to experimental TBI, using the controlled cortical impact (CCI) model. In and around the contusion, we observed alterations of miRNAs associated with dementia/AD, compared to the contralateral side. Specifically, the expression of miR-9 was significantly upregulated, while miR-29b, miR-34a, miR-106b, miR-181a and miR-107 were downregulated. Via qPCR, we confirmed these results in an additional group of injured rats when compared to naïve animals. Interestingly, the changes in those miRNAs were concomitant with alterations in the gene expression of mRNAs involved in amyloid generation and tau pathology, such as β-APP cleaving enzyme (BACE1) and Glycogen synthase-3-β (GSK3β). In addition increased levels of neuroinflammatory markers (TNF-α), glial activation, neuronal loss, and tau phosphorylation were observed in pericontusional areas. Therefore, our results suggest that the secondary injury cascade in TBI affects miRNAs regulating the expression of genes involved in AD dementia
Desarrollo de un método de cribado de fármacos para identificar nuevas drogas capaces de revertir el fenotipo resistente de las células cancerosas a la destrucción por células CAR-T.
En los últimos años, la terapia de células T con receptor de antígeno quimérico (CAR) se
ha convertido en un tratamiento prometedor para el tratamiento del cáncer. A pesar de
este progreso, una proporción significativa de pacientes experimenta resistencia a la
terapia CAR-T. Las células cancerosas pueden ser insensibles a la destrucción por las
células CAR-T, lo que se conoce como resistencia intrínseca. Esta resistencia intrínseca
es responsable de una parte muy significativa del fracaso de este tipo de terapias que
afecta a todo tipo de tumores, siendo una dificultad adicional para la eficacia de las células
CAR-T en el tratamiento de tumores sólidos. Mucho de los mecanismos de resistencia
intrínseca están regulados a nivel epigenético. Recientemente, se han desarrollado y
probado varios inhibidores epigenéticos en cáncer. El enfoque principal de la mayoría de
los estudios hasta ahora ha sido el efecto citotóxico directo de estos compuestos, y pocos
estudios han investigado la capacidad de revertir el fenotipo resistente de las células
cancerosas a la terapia CAR-T. Existe la necesidad de una metodología sistemática para
identificar nuevas drogas que sensibilicen a la célula tumoral a la destrucción por las
células CAR-T. Mediante la expresión de flaying luciferase (fLuc) en líneas murinas de
tumores sólidos que expresan el antígeno EGFRvIII, hemos establecido un protocolo
simple, preciso, sensible y robusto para detectar sensibilizadores epigenéticos.
Demostramos la eficacia de nuestro protocolo e identificamos varios inhibidores
epigenéticos capaces de sensibilizar a las células tumorales a la destrucción por un CAR
anti-EGFRvIII
Rumen bacterial community evaluated by 454 pyrosequencing and terminal restriction fragment length polymorphism analyses in dairy sheep fed marine algae
Intermediation for technology diffusion and user innovation in a developing rural economy:a social learning perspective
Technology intermediaries are seen as potent vehicles for addressing perennial problems in transferring technology from university to industry in developed and developing countries. This paper examines what constitutes effective user-end intermediation in a low-technology, developing economy context, which is an under-researched topic. The social learning in technological innovation framework is extended using situated learning theory in a longitudinal instrumental case study of an exemplar technology intermediation programme. The paper documents the role that academic-related research and advisory centres can play as intermediaries in brokering, facilitating and configuring technology, against the backdrop of a group of small-scale pisciculture businesses in a rural area of Colombia. In doing so, it demonstrates how technology intermediation activities can be optimized in the domestication and innofusion of technology amongst end-users. The design components featured in this instrumental case of intermediation can inform policy making and practice relating to technology transfer from university to rural industry. Future research on this subject should consider the intermediation components put forward, as well as the impact of such interventions, in different countries and industrial sectors. Such research would allow for theoretical replication and help improve technology domestication and innofusion in different contexts, especially in less-developed countries
The Presampler for the Forward and Rear Calorimeter in the ZEUS Detector
The ZEUS detector at HERA has been supplemented with a presampler detector in
front of the forward and rear calorimeters. It consists of a segmented
scintillator array read out with wavelength-shifting fibers. We discuss its
desi gn, construction and performance. Test beam data obtained with a prototype
presampler and the ZEUS prototype calorimeter demonstrate the main function of
this detector, i.e. the correction for the energy lost by an electron
interacting in inactive material in front of the calorimeter.Comment: 20 pages including 16 figure
The economic geography of the meso-global spaces: integrating multinationals and clusters at the local-global level
This is an author's accepted manuscript of an article published in:
“European Planning Studies"; Volume 21, Issue 7, 2013; copyright Taylor & Francis; available online at: http://dx.doi.org/10.1080/09654313.2013.733853[EN] The local global phenomenon literature is fragmented between the fields of
international business and economic geography (EG). In the case of the latter, the literature,
produced within the global production networks (GPNs) and global value chain frameworks, does
not address the central role of firms, especially multinationals which co-locate and connect
territories along GPNs. This paper develops a cross-field conceptual integration in order to
enrich the EG perspective, using qualitative research methodology to test the framework. The
results have important implications for scholars and policymakers.We are very thankful to the “Ministry of Economics” funding ECO2010:17318 and “Generalitat Valenciana” for its support in visiting the London School of Economics and Political Science (BEST 2011 grants)Hervás Oliver, JL.; Boix Domenech, R. (2012). The economic geography of the meso-global spaces: integrating multinationals and clusters at the local-global level. European Planning Studies. 21(7):1064-1080. https://doi.org/10.1080/09654313.2013.733853S1064108021
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