1,827 research outputs found
A general perspective of the characterization and quantification of nanoparticles: Imaging, spectroscopic, and separation techniques
This article gives an overview of the different techniques used to identify, characterize, and quantify engineered nanoparticles (ENPs). The state-of-the-art of the field is summarized, and the different characterization techniques have been grouped according to the information they can provide. In addition, some selected applications are highlighted for each technique. The classification of the techniques has been carried out according to the main physical and chemical properties of the nanoparticles such as morphology, size, polydispersity characteristics, structural information, and elemental composition. Microscopy techniques including optical, electron and X-ray microscopy, and separation techniques with and without hyphenated detection systems are discussed. For each of these groups, a brief description of the techniques, specific features, and concepts, as well as several examples, are described.Junta de Andalucía FQM-5974CEI-Biotic Granada CEI2013- MP-1
Assisting dependent people at home through autonomous unmanned aerial vehicles
This work describes a proposal of autonomous unmanned aerial vehicles (AUAVs) for home assistance of dependent people. AUAVs will monitor and recognize human activities during flight to improve their quality of life. However, before bringing such AUAV assistance to real homes, several challenges must be faced to make them viable and practical. Some challenges are technical and some others are related to human factors. In particular, several technical aspects are described for AUAV assistance: (1) flight control, based on our active disturbance rejection control algorithm, (2) flight planning (navigation in obstacle environments), and, (3) processing signals, acquired both from flight-control and monitoring sensors. From the assisted person’s viewpoint, our research focuses on three cues: (1) the user’s perception about AUAV assistance, (2) the influence on human acceptance of AUAV appearance and behavior at home, and (3) the human-robot interaction between assistant AUAV and assisted person. Finally, virtual reality environments are proposed to carry out preliminary tests and user acceptance evaluations.This work has been partially supported by Spanish Ministerio de Ciencia, Innovación y Universidades, Agencia Estatal de Investigaci´on (AEI) / European Regional Development Fund (FEDER, UE) under DPI2016-80894-R grant, and by CIBERSAM of the Instituto de Salud Carlos III. Lidia M. Belmonte holds FPU014/05283 scholarship from Spanish Ministerio de Educaci´on y Formación Profesional
Fístula arteriovenosa postraumática: tratamiento endovascular. Revisión de la literatura y presentación de un caso clínico
ResumenLas fístulas arteriovenosas en la cabeza y el cuello son entidades poco frecuentes. La mayoría es secundaria a heridas penetrantes por arma blanca. Se describe el tratamiento exitoso mediante cirugía endovascular de una fístula postraumática tras una herida penetrante entre la arteria maxilar interna izquierda y la vena yugular externa. A través de este caso clínico y la revisión de la literatura se ilustran las causas, manifestaciones, estudio radiológico y tratamiento de una fístula postraumática entre la arteria maxilar interna y la vena yugular externa. A través de este caso clínico se demuestra la utilidad de los procedimientos endovasculares en el tratamiento de estas complicaciones.AbstractTraumatic arteriovenous fistulas of the head and neck region are uncommon. The majority are due to penetration of blunt injury. We describe a successful endovascular treatment of a posttraumatic fistula between the left maxillary artery and the external jugular vein due to a penetration injury. This case and a review of the literature illustrate the causes, manifestations, image studies and treatment for a posttraumatic fistula between the maxillary artery and the external jugular vein. This case demonstrate the utility of endovascular treatment of head and neck injuries complications
Range Shifts in the Worldwide Expansion of Oenothera drummondii subsp. drummondii, a Plant Species of Coastal Dunes
Oenothera drummondii is a coastal dunes plant species from the North American continent that has affected the natural structure and dynamics of Spanish, Israeli, and Chinese shores as an invasive species. In South Africa, Australia, New Zealand, and France, it is reported as a naturalized species. Ecological niche and species distribution modeling has been widely used as a tool to find potential global invasions and assess invasion effects. Herein, we modeled the ecological niche and the potential distribution of Oenothera drummondii, using the Köppen–Geiger climate classification, bioclimatic variables and occurrence records that have been validated in their native and non-native distribution. In the native area, the temperature and precipitation values are higher compared to non-native zones, where the low temperatures and the absence of humidity are the main climatic limitations for the species. In the environmental space, new distribution areas were identified and a partial overlap between the native and non-native niches detected. This suggests that climate matching is not occurring for the species, and that the potential invasion of coastal dune areas seems to be higher than previously observed. Therefore, new potential invasion areas, where the species is not yet distributed, were also identified. Our predictions could be used to establish ecosystem management measures to mitigate the invasion of Oenothera drummondii, helping to prevent possible negative impacts on fragile coastal ecosystems.Mexican Centre for Innovation in Ocean Energy FSE-2014-06-249795Ministerio de Economía y Competitividad CGL2015-65058-
Examining the mediating role of motivation in the relationship between multidimensional perfectionism and well- and ill-being in vocational dancers.
: Perfectionism is considered to be an important personality factor within the dance context given the high number of dancers whose psychological health is influenced by its consequences. The relationship between perfectionism and dancers' well- and ill-being can be mediated by a range of variables. The present study explores the role of forms of motivation (i.e., autonomous motivation, controlled motivation and amotivation) as mediators in the relationship between perfectionism (i.e., self-oriented and socially prescribed) and an indicator of well-being (i.e., subjective vitality) and ill-being (i.e., burnout). Participants of the study were 146 male and female Spanish vocational dancers aged between 12 and 26 years old (Mean age = 15.40 ± 2.96) who completed questionnaires measuring the variables of interest. Results of multiple mediator regression analyses showed that amotivation mediated the relationships between self-oriented and socially prescribed perfectionism with burnout and subjective vitality. Self-oriented perfectionism was negatively correlated, and socially prescribed perfectionism positively associated with amotivation. Amotivation of dancers was a positive predictor of burnout and a negative predictor of subjective vitality. Overall, the findings corroborate the importance of amotivation in the relationship between perfectionism dimensions and well-being and ill-being in dancers
Gestational hypothyroxinemia affects its offspring with a reduced suppressive capacity impairing the outcome of the experimental autoimmune encephalomyelitis
Indexación: Scopus.Hypothyroxinemia (Hpx) is a thyroid hormone deficiency (THD) condition highly frequent during pregnancy, which although asymptomatic for the mother, it can impair the cognitive function of the offspring. Previous studies have shown that maternal hypothyroidism increases the severity of experimental autoimmune encephalomyelitis (EAE), an autoimmune disease model for multiple sclerosis (MS). Here, we analyzed the immune response after EAE induction in the adult offspring gestated in Hpx. Mice gestated in Hpx showed an early appearance of EAE symptoms and the increase of all parameters of the disease such as: the pathological score, spinal cord demyelination, and immune cell infiltration in comparison to the adult offspring gestated in euthyroidism. Isolated CD4+CD25+ T cells from spleen of the offspring gestated in Hpx that suffer EAE showed reduced capacity to suppress proliferation of effector T cells (TEff) after being stimulated with anti-CD3 and anti-CD28 antibodies. Moreover, adoptive transfer experiments of CD4+CD25+ T cells from the offspring gestated in Hpx suffering EAE to mice that were induced with EAE showed that the receptor mice suffer more intense EAE pathological score. Even though, no significant differences were detected in the frequency of Treg cells and IL-10 content in the blood, spleen, and brain between mice gestated in Hpx or euthyroidism, T cells CD4+CD25+ from spleen have reduced capacity to differentiate in vitro to Treg and to produce IL-10. Thus, our data support the notion that maternal Hpx can imprint the immune response of the offspring suffering EAE probably due to a reduced capacity to trigger suppression. Such "imprints" on the immune system could contribute to explaining as to why adult offspring gestated in Hpx suffer earlier and more intense EAE. © 2018 Haensgen, Albornoz, Opazo, Bugueño, Jara Fernández, Binzberger, Rivero-Castillo, Venegas Salas, Simon, Cabello-Verrugio, Elorza, Kalergis, Bueno and Riedel.https://www.frontiersin.org/articles/10.3389/fimmu.2018.01257/ful
Determinación de aflatoxinas en maíz y productos derivados por cromatografía líquida de alta resolución
A study is pressented about the extraction and analysis of aflatoxins in contaminated corn and corn products. The extraction is carried out in a single step grounding the sample, packing it in a glass column and pouring choloform through it. On this way high recoveries are obtained. The quantitation is made by reserve phase H.P.L.C. using fluorescence detection of derivatives of the aflatoxins.Se presenta un estudio sobre la extracción de aflatoxinas de maíz y productos derivados contaminados, así como su análisis por cromatografía líquida de alta resolución. La extracción se lleva a cabo en un sólo paso moliendo la muestra, empacándola en una columna y percolando cloroformo a través de ella. En esta forma se logran unos porcentajes de recuperación mucho más altos que por los métodos tradicionales. El análisis se efectuó por cromatografía líquida en fase inversa. y detección por fluorescencia. con formación pre-via de derivados de las aflatoxinas
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