4,955 research outputs found
The influence of age, strength and stiffness on proprioception in knee osteoarthritis
info:eu-repo/semantics/publishedVersio
Normalization procedure for relaxation studies in NMR quantum information processing
NMR quantum information processing studies rely on the reconstruction of the
density matrix representing the so-called pseudo-pure states (PPS). An
initially pure part of a PPS state undergoes unitary and non-unitary
(relaxation) transformations during a computation process, causing a "loss of
purity" until the equilibrium is reached. Besides, upon relaxation, the nuclear
polarization varies in time, a fact which must be taken into account when
comparing density matrices at different instants. Attempting to use time-fixed
normalization procedures when relaxation is present, leads to various anomalies
on matrices populations. On this paper we propose a method which takes into
account the time-dependence of the normalization factor. From a generic form
for the deviation density matrix an expression for the relaxing initial pure
state is deduced. The method is exemplified with an experiment of relaxation of
the concurrence of a pseudo-entangled state, which exhibits the phenomenon of
sudden death, and the relaxation of the Wigner function of a pseudo-cat state.Comment: 9 pages, 5 figures, to appear in QI
Writing electronic ferromagnetic states in a high-temperature paramagnetic nuclear spin system
In this paper we use the Nuclear Magnetic Resonance (NMR) to write eletronic
states of a ferromagnetic system into a high-temperature paramagnetic nuclear
spins. Through the control of phase and duration of radiofrequency pulses we
set the NMR density matrix populations, and apply the technique of quantum
state tomography to experimentally obtain the matrix elements of the system,
from which we calculate the temperature dependence of magnetization for
different magnetic fields. The effects of the variation of temperature and
magnetic field over the populations can be mapped in the angles of spins
rotations, carried out by the RF pulses. The experimental results are compared
to the Brillouin functions of ferromagnetic ordered systems in the mean field
approximation for two cases: the mean field is given by (i)
and (ii) , where is the external
magnetic field, and are mean field parameters. The
first case exhibits second order transition, whereas the second case has first
order transition with temperature hysteresis. The NMR simulations are in good
agreement with the magnetic predictions
Gastric cancer extracellular vesicles tune the migration and invasion of epithelial and mesenchymal cells in a histotype-dependent manner
Extracellular vesicles (EVs) secreted by tumor cells modulate recipient cellsâ behavior, but their effects in normal cells from the tumor microenvironment remain poorly known. In this study, we dissected the functional impact of gastric cancer cell-derived EVs (GC-EVs), representative of distinct GC histotypes, on the behavior of normal isogenic epithelial and mesenchymal cells. GC-EVs were isolated by differential centrifugation and characterized by transmission electron microscopy, nanoparticle tracking analysis, and imaging flow-cytometry. Epithelial and mesenchymal cells were challenged with GC-EVs and submitted to proliferation, migration, and invasion assays. Expression of epithelial and mesenchymal markers was followed by immunofluorescence and flow-cytometry. Our results indicated that GC-EVs secreted by diffuse-type cancer cells decrease the migration of recipient cells. This effect was more prominent and persistent for mesenchymal recipient cells, which also increased Fibronectin expression in response to EVs. GC-EVs secreted by cancer cells derived from tumors with an intestinal component increased invasion of recipient epithelial cells, without changes in EMT markers. In summary, this study demonstrated that GC-EVs modulate the migration and invasion of epithelial and mesenchymal cells from the tumor microenvironment, in a histotype-dependent manner, highlighting new features of intestinal and diffuse-type GC cells, which may help explaining differential metastasis patterns and aggressiveness of GC histotypes.Ipatimup integrate the i3S Research Unit, which is partially supported by FCT, the Portuguese Foundation for Science and Technology. This work was supported by (1) FEDERâFundo Europeu de Desenvolvimento Regional funds through the COMPETE 2020âOperacional Programme for Competitiveness and Internationalisation (POCI), Portugal 2020, and by Portuguese funds through Portuguese Science and Technology Foundation (FCT)/MinistĂ©rio da CiĂȘncia, Tecnologia e Inovação in the framework of the project âInstitute for Research and Innovation in Health Sciencesâ (POCI-01-0145-FEDER-007274); (2) the project NORTE-01-0145-FEDER-000029, supported by Norte Portugal Regional Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF); (3) Portuguese FCT with the Grant Reference PTDC/BBB-ECT/2518/2014; (4) FCT PhD Programmes and by Programa Operacional Potencial Humano (POCH), specifically by the BiotechHealth Programe (Doctoral Programme on Cellular and Molecular Biotechnology Applied to Health Sciences); (5) Ipatimup Board of Directors: Project âThe role of gastric cancer cell-derived extracellular vesiclesâ; and (6) FCT fellowships PD/BD/128406/2017 to SR, SFRH/BPD/86543/2012 to JC, and SFRH/BPD/89764/2012 to PO
Space of memory and representation: Bouça da Cova da Moura (Ardegães, Maia, Northwest of Portugal): a case study
Bouça da Cova da Moura is the local place-name attributed to a stretch of a plateau overlooking the Leça valley. Here,
Neolithic burial mounds share their landscape setting with scatters of archaeological materials that include Bell Beaker fragments,
idols and metalwork. Since these are mostly surface findings, their contexts have not yet been accurately determined. Another significant feature is the presence of prehistoric rock carvings. The plateau may thus be considered a public space, conceptually and physically built over time. Its significance and meanings were certainly created and transmitted through practices of memory construction which are representative of cultural identity and social cohesion.Le site de Bouça da Cova da Moura se trouve sur un plateau faisant face au Rio Leça. On y a identifié des tertres
funĂ©raires du NĂ©olithique, auxquels sont associĂ©s des zones de concentration dâartefacts, incluant cĂ©ramiques campaniformes, idoles
et mobilier mĂ©tallique. Sâagissant de mobilier de surface, le contexte de ces diffĂ©rentes concentrations nâa pas Ă©tĂ© dĂ©terminĂ© avec
attention. Un autre fait significatif est lâapparition de gravures rupestres prĂ©historiques. On peut considĂ©rer le plateau comme un espace publique, qui sâest bĂąti physiquement et conceptuellement au cours des temps. Son importance et sa signification ont certainement Ă©tĂ© crĂ©Ă©es et transmises Ă travers un certain nombre de pratiques de construction mĂ©morielle, reprĂ©sentatives de lâidentitĂ© culturelle et de la cohĂ©sion sociale.info:eu-repo/semantics/publishedVersio
Space of memory and representation : Bouça da Cova da Moura (Ardegães, Maia, Northwest of Portugal)
Bouça da Cova da Moura is the local place-name attributed to a stretch of a plateau overlooking the Leça valley. Here,
Neolithic burial mounds share their landscape setting with scatters of archaeological materials that include Bell Beaker fragments,
idols and metalwork. Since these are mostly surface findings, their contexts have not yet been accurately determined. Another
significant feature is the presence of prehistoric rock carvings. The plateau may thus be considered a public space, conceptually and
physically built over time. Its significance and meanings were certainly created and transmitted through practices of memory
construction which are representative of cultural identity and social cohesion.Le site de Bouça da Cova da Moura se trouve sur un plateau faisant face au Rio Leça. On y a identifié des tertres
funĂ©raires du NĂ©olithique, auxquels sont associĂ©s des zones de concentration dâartefacts, incluant cĂ©ramiques campaniformes, idoles
et mobilier mĂ©tallique. Sâagissant de mobilier de surface, le contexte de ces diffĂ©rentes concentrations nâa pas Ă©tĂ© dĂ©terminĂ© avec
attention. Un autre fait significatif est lâapparition de gravures rupestres prĂ©historiques. On peut considĂ©rer le plateau comme un
espace publique, qui sâest bĂąti physiquement et conceptuellement au cours des temps. Son importance et sa signification ont
certainement été créées et transmises à travers un certain nombre de pratiques de construction mémorielle, représentatives de
lâidentitĂ© culturelle et de la cohĂ©sion sociale
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