2,427 research outputs found

    La crisis humanitaria de los refugiados ucranianos en la prensa española

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    La presente investigación analiza el tratamiento de la crisis humanitaria de los refugiados ucranianos en la prensa española. Para ello, se llevó a cabo un análisis de contenido cuantitativo aplicado a una muestra de 77 noticias publicadas por los principales diarios españoles digitales: El País y El Mundo. A partir de los resultados obtenidos, se ha concluido que la representación de la crisis humanitaria de los refugiados ucranianos en la prensa española es de carácter positivo. De este modo, la cobertura se enfoca en la acogida de los refugiados en el territorio nacional, la integración de las personas refugiadas en el país destino, al igual que la situación de vulnerabilidad y riesgo que enfrenta este colectivo provocado por el conflicto bélico entre Rusia y Ucrania

    The influence of dynamics and speech on understanding humanoid facial expressions

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    Human communication relies mostly on nonverbal signals expressed through body language. Facial expressions, in particular, convey emotional information that allows people involved in social interactions to mutually judge the emotional states and to adjust its behavior appropriately. First studies aimed at investigating the recognition of facial expressions were based on static stimuli. However, facial expressions are rarely static, especially in everyday social interactions. Therefore, it has been hypothesized that the dynamics inherent in a facial expression could be fundamental in understanding its meaning. In addition, it has been demonstrated that nonlinguistic and linguistic information can contribute to reinforce the meaning of a facial expression making it easier to be recognized. Nevertheless, few studies have been performed on realistic humanoid robots. This experimental work aimed at demonstrating the human-like expressive capability of a humanoid robot by examining whether the effect of motion and vocal content influenced the perception of its facial expressions. The first part of the experiment aimed at studying the recognition capability of two kinds of stimuli related to the six basic expressions (i.e. anger, disgust, fear, happiness, sadness, and surprise): static stimuli, that is, photographs, and dynamic stimuli, that is, video recordings. The second and third parts were focused on comparing the same six basic expressions performed by a virtual avatar and by a physical robot under three different conditions: (1) muted facial expressions, (2) facial expressions with nonlinguistic vocalizations, and (3) facial expressions with an emotionally neutral verbal sentence. The results show that static stimuli performed by a human being and by the robot were more ambiguous than the corresponding dynamic stimuli on which motion and vocalization were associated. This hypothesis has been also investigated with a 3-dimensional replica of the physical robot demonstrating that even in case of a virtual avatar, dynamic and vocalization improve the emotional conveying capability

    Pollutants monitoring and air quality evaluation in a confined environment: The ‘Majesty’ of Ambrogio Lorenzetti in the St. Augustine Church in Siena (Italy)

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    A monitoring campaign of the levels of some organic contaminants, such as polycyclic aromatic hydrocarbons (PAHs), perfluoro alkylated substances (PFASs), chlorinated pesticides (4 isomers of hexachlorocyclohexane, hexachlorobenzene, 6 isomers and metabolites of DDT and dieldrin), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs), in different matrices (dust taken from the floor and under a wall painting and fragments of the 'Majesty' wall painting by Ambrogio Lorenzetti), was conducted in the historical museum of St. Augustine's church in Siena (Italy). Instrumental analyses were made by gas chromatography and liquid chromatography coupled with mass spectrometry. The results showed the presence of some organic pollutants (PAHs and PBDEs), whose interaction with the surfaces of works of art are not yet fully elucidated. The study was complemented by monitoring the air quality inside and outside the church for the detection of volatile organic compounds (VOCs); all the results showed low levels of air pollution. Copyright (C)2016 Turkish National Committee for Air Pollution Research and Control

    Light-Switchable Membrane Permeability in Giant Unilamellar Vesicles

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    : In this work, giant unilamellar vesicles (GUVs) were synthesized by blending the natural phospholipid 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) with a photoswitchable amphiphile (1) that undergoes photoisomerization upon irradiation with UV-A (E to Z) and blue (Z to E) light. The mixed vesicles showed marked changes in behavior in response to UV light, including changes in morphology and the opening of pores. The fine control of membrane permeability with consequent cargo release could be attained by modulating either the UV irradiation intensity or the membrane composition. As a proof of concept, the photocontrolled release of sucrose from mixed GUVs is demonstrated using microscopy (phase contrast) and confocal studies. The permeability of the GUVs to sucrose could be increased to ~4 × 10-2 μm/s when the system was illuminated by UV light. With respect to previously reported systems (entirely composed of synthetic amphiphiles), our findings demonstrate the potential of photosensitive GUVs that are mainly composed of natural lipids to be used in medical and biomedical applications, such as targeted drug delivery and localized topical treatments

    Non-autonomous zinc–methylimidazole oscillator and the formation of layered precipitation structures in a hydrogel

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    Oscillations are one of the intrinsic features of many animate and inanimate systems. The oscillations manifest in the temporal periodic change of one or several physical quantities describing the systems. In chemistry and biology, this physical quantity is the concentration of the chemical species. In most chemical oscillatory systems operating in batch or open reactors, the oscillations persist because of the sophisticated chemical reaction networks incorporating autocatalysis and negative feedback. However, similar oscillations can be generated by periodically changing the environment providing non-autonomous oscillatory systems. Here we present a new strategy for designing a non-autonomous chemical oscillatory system for the zinc–methylimidazole. The oscillations manifested in the periodic change of the turbidity utilizing the precipitation reaction between the zinc ions and 2-methylimidazole (2-met) followed by a partial dissolution of the formed precipitate due to a synergetic effect governed by the ratio of the 2-met in the system. Extending our idea spatiotemporally, we also show that these precipitation and dissolution phenomena can be utilized to create layered precipitation structures in a solid agarose hydrogel

    Periodic Precipitation of Zeolitic Imidazolate Frameworks in a Gelled Medium

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    Formation of spatially periodic patterns is a ubiquitous process in nature and man-made systems. Periodic precipitation is the oldest type of pattern formation, in which the formed colloid particles are self-assembled into a sequence of spatially separated precipitation zones in solid hydrogels. Chemical systems exhibiting periodic precipitation mostly comprise oppositely charged inorganic ions. Here, we present a new sub-group of this phenomenon driven by the diffusion and reaction of several transition metal cations (Zn2+, Co2+, Cd2+, Cu2+, Fe2+, Mn2+, and Ni2+) with an organic linker (2-methylimidazole) producing periodic precipitation of zeolitic imidazolate frameworks. In some cases, the formed crystals reached the size of ∼50 μm showing that a gel matrix can provide optimal conditions for nucleation and crystal growth. We investigated the effect of the gel concentration and solvent composition on the morphology of the pattern. To support the experimental observations, we developed a reaction–diffusion model, which qualitatively describes the spatially periodic pattern formation

    Hematopoietic differentiation: a coordinated dynamical process towards attractor stable states

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    <p>Abstract</p> <p>Background</p> <p>The differentiation process, proceeding from stem cells towards the different committed cell types, can be considered as a trajectory towards an attractor of a dynamical process. This view, taking into consideration the transcriptome and miRNome dynamics considered as a whole, instead of looking at few 'master genes' driving the system, offers a novel perspective on this phenomenon. We investigated the 'differentiation trajectories' of the hematopoietic system considering a genome-wide scenario.</p> <p>Results</p> <p>We developed serum-free liquid suspension unilineage cultures of cord blood (CB) CD34<sup>+ </sup>hematopoietic progenitor cells through erythroid (E), megakaryocytic (MK), granulocytic (G) and monocytic (Mo) pathways. These cultures recapitulate physiological hematopoiesis, allowing the analysis of almost pure unilineage precursors starting from initial differentiation of HPCs until terminal maturation. By analyzing the expression profile of protein coding genes and microRNAs in unilineage CB E, MK, G and Mo cultures, at sequential stages of differentiation and maturation, we observed a coordinated, fully interconnected and scalable character of cell population behaviour in both transcriptome and miRNome spaces reminiscent of an attractor-like dynamics. MiRNome and transcriptome space differed for a still not terminally committed behaviour of microRNAs.</p> <p>Conclusions</p> <p>Consistent with their roles, the transcriptome system can be considered as the state space of a cell population, while the continuously evolving miRNA space corresponds to the tuning system necessary to reach the attractor. The behaviour of miRNA machinery could be of great relevance not only for the promise of reversing the differentiated state but even for tumor biology.</p
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