2,719 research outputs found
Approaching stimuli bias attention in numerical space
Increasing evidence suggests that common mechanisms underlie the direction of attention in physical space and numerical space, along the mental number line. The small leftward bias (pseudoneglect) found on paper-and-pencil line bisection is also observed when participants ‘bisect’ number pairs, estimating (without calculating) the number midway between two others. Here we investigated the effect of stimulus motion on attention in numerical space. A two-frame apparent motion paradigm manipulating stimulus size was used to produce the impression that pairs of numbers were approaching (size increase from first to second frame), receding (size decrease), or not moving (no size change). The magnitude of pseudoneglect increased for approaching numbers, even when the final stimulus size was held constant. This result is consistent with previous findings that pseudoneglect in numerical space (as in physical space) increases as stimuli are brought closer to the participant. It also suggests that the perception of stimulus motion modulates attention over the mental number line and provides further support for a connection between the neural representations of physical space and number
Bone lengthening osteogenesis, a combination of intramembranous and endochondral ossification: an experimental study in sheep
We evaluated the morphological features of the newly formed tissue in an experimental model of tibial callotasis lengthening on 24 lambs, aged from 2 to 3 months at the time of operation. A unilateral external fixator prototype Monotube Triax® (Stryker Howmedica Osteonics, New Jersey) was applied to the left tibia. A percutaneous osteotomy was performed in a minimally traumatic manner using a chisel. Lengthening was started 7 days after surgery and was continued to 30 mm. The 24 animals were randomly divided into three groups of 8 animals each: in Group 1, lengthening took place at a rate of 1 mm/day for 30 days; in Group 2, at a rate of 2 mm/day for 15 days; in Group 3, at a rate of 3 mm/day for 10 days. In each group, 4 animals were killed 2 weeks after end of lengthening, and the other 4 animals at 4 weeks after end of lengthening. To assess bony formation in the distraction area, radiographs were taken every 2 weeks from the day of surgery. To study the process of vascularization, we used Spalteholz’s technique. After killing, the tibia of each animal was harvested, and sections were stained with hematoxylin and eosin, Masson’s trichrome, and Safranin-O. Immunohistochemistry was performed, using specific antibodies to detect collagens I and II, S100 protein, and fibronectin. A combination of intramembranous and endochondral ossification occurred together at the site of distraction. Our study provides a detailed structural characterization of the newly formed tissue in an experimental model of tibial lengthening in sheep and may be useful for further investigations on callotasis
Advances in Meniscal Tissue Engineering
Meniscal tears are the most common knee injuries and have a poor ability of healing. In the last few decades, several techniques have been increasingly used to optimize meniscal healing. Current research efforts of tissue engineering try to combine cell-based therapy, growth factors, gene therapy, and reabsorbable scaffolds to promote healing of meniscal defects. Preliminary studies did not allow to draw definitive conclusions on the use of these techniques for routine management of meniscal lesions. We performed a review of the available literature on current techniques of tissue engineering for the management of meniscal tears
Physico-Chemical Characterization of Methanolic Mixtures of Cholinium Dihydrogen Phosphate-Based DES
[Abstract] The biocompatibility of three deep eutectic solvents based on cholinium dihydrogen phosphate for their use in lipase-catalyzed reactions was recently demonstrated, so the possible application as cosolvents with methanol in transesterification processes demands an exhaustive characterization of the physical properties. Thus, in this work binary and ternary deep eutectic solvents composed of the abovementioned salt as hydrogen bond acceptor and ethyleneglycol and/or glycerol as hydrogen bond donors were synthesized and mixed with methanol. The density, refractive index, electrical conductivity and dynamic viscosity were determined between 293.15 K and 323.15 K. The experimental data were correlated with different well-known equations and derived magnitudes like excess molar volumes, changes of refractive index on mixing and viscosity deviations were inferred in order to get an in-depth characterization of the studied mixtures with cholinium dihydrogen phosphate-based DES. The most intriguing data observed is the great peak measured for ionic conductivity at very high methanol concentration, which is difficult to explain even with the most recent theoretical models.The authors are grateful to Spanish Ministry of Science, Innovation and Universities for the financial support through the project RTI2018-094702-B-I00. The authors thank Xunta de Galicia and ERDF for funding through a postdoctoral grant (ED481D-2019/017) and Universidade de Vigo/CISUG for funding open access chargeXunta de Galicia; ED481D-2019/01
Vacuum tribological behaviour of self lubricant quasicrystalline composite coatings
High temperature resistant self-lubricant coatings are needed in space vehicles for components that operate at high temperatures and/or under vacuum. Thick composite lubricant coatings containing quasicrystalline alloys (QC) as the hard phase for wear resistance, have been deposited by thermal spray. The coatings also comprise lubricating materials (silver and BaF2-CaF2 eutectic) and NiCr as the tough component. This paper describes the vacuum tribological properties of TH103, a coating belonging to this family, with excellent microstructural quality. The coating was deposited by HVOF and tested under vacuum on a pin-on-disc tribometer. Different loads, linear speeds and pin materials were studied. The pin scars and disc wear tracks were characterized by EDS-SEM. A minimum mean steady friction coefficient of 0.32 was obtained employing a X-750 Ni superalloy pin in vacuum conditions under 10 N load and 15 cm/s linear speed, showing moderate wear of the disc and low wear of the pin
Ni-sepiolita en depósitos de lateritas de República Dominicana: variaciones composicionales
Depto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasTRUEpu
Synthesis and characterization of a click-assembled 18-atom macrocycle that displays selective AXL kinase inhibitory activity
A novel macrocyclic construct consisting of a pyrazolopyrimidine scaffold concatenated to a benzene ring
through two triazoles has been developed to investigate uncharted chemical space with bioactive potential. The 18-atom
macrocycle was assembled via a double copper-catalyzed alkyne−azide cycloaddition (CuAAC) reaction between 1,3-
bis(azidomethyl)benzene and a bis-propargylated pyrazolo[3,4-d]pyrimidine core. The resulting macrocycle was functionalized
further into a multicyclic analog that displays selective inhibitory activity against the receptor tyrosine kinase AXL.O.C.-L. and B.L. thank Spain Ministry of Education, Culture
and Sport and the Erasmus + Traineeship programme for
funding, respectively. C.T. thanks the CMVM for a Principal’s
Scholarship. F.F. acknowledges support from Universidad de
Granada. SHM and AU-B are grateful to Scottish Power and
CRUK for funding
Heavy metals removal from soil/sediments washing effluents via biocompatible aqueous two-phase systems
The generation of high amounts of soil/sediment washing solutions is one of the main concerns faced in ex situ treatment techniques, so in the present research, we have demonstrated the suitability of an organic salt like sodium potassium tartrate to efficiently promote phase segregation in a model soil washing solution containing biodegradable non-ionic-surfactants (Tween 80 and Tergitol 15S9) and heavy metals (copper, zinc, and cadmium), after a preliminary screening of the demixing effect of different inorganic and organic salts like ammonium nitrate, ammonium acetate and sodium potassium tartrate. The aqueous two-phase systems were characterized in depth at room temperature by defining the immiscibility region and correlating the experimental data with three empirical equations, and the results were discussed in the light of a thermodynamic function like the Gibbs free energy of hydration. Then, the applicability to extract the abovementioned metal ions was researched after TLs determination, observing high heavy metals extraction percentage (over 80 % in some cases). The extraction process was included in the soil washing process at real scale and it was simulated by means of the software SuperPro Designer, that makes up a valuable tool to ease the analysis of the technical viability of the proposed strategy.Universidade de Vigo/CISU
Effect of oxidizing and reducing atmospheres on Ba(Ti0.90Zr0.10)O3:2V ceramics as characterized by piezoresponse force microscopy
The effect of annealing atmospheres (At amb, N2 and O2) on the electrical properties of Ba(Ti0.90Zr0.10)O3:2V (BZT10:2V) ceramics obtained by the mixed oxide method was investigated. X-ray photoelectron spectroscopy (XPS) analysis indicates that oxygen vacancies present near Zr and Ti ions reduce ferroelectric properties, especially in samples treated in an ambient atmosphere (At amb). BZT10:2V ceramics sintered in a nitrogen atmosphere showed better dielectric behaviour at room temperature with a dielectric permittivity measured at a frequency of 10 kHz equal to 16800 with dielectric loss of 0.023. Piezoelectric force microscopy (PFM) images reveal improvement in the piezoelectric coefficient by sintering the sample under nitrogen atmosphere. Thus, BZT10:2V ceramics sintered under a nitrogen atmosphere can be useful for practical applications which include nonvolatile digital memories, spintronics and data-storage media
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