278 research outputs found
La importancia de las relaciones investigador-investigado: el caso de las narrativas de vida profesional
Este artículo aborda un tema fundamental en los estudios llevados a cabo
desde una perspectiva construccionista y narrativa: el de la relación entre
investigadores e investigados. Nuestra aportación se basa en la elaboración
de nueve microetnografías, en las que hemos tenido en cuenta de forma
especial la dimensión biográfica, con nueve docentes de enseñanza primaria,
lo que nos ha permitido: a) poner de manifiesto la importancia de explicitar la
relación entre investigadores e investigados; b) examinar las fortalezas y las
debilidades de cada tipo y modalidad de relación; c) apuntar la complejidad y
el dinamismo de los elementos que configuran las relaciones; d) abrir vía de
indagación que puede contribuir a profundizar en los aspectos relacionales que
subyacen a la construcción social del conocimientoThis paper addresses a fundamental issue in the studies carried out from a
constructionist and narrative perspective: the relationship between researchers
and researched. Our contribution is based on the development of nine microethnographies,
in which the biographical dimension had a special consideration,
with nine primary school teachers. This has allowed us to: a) highlight the
importance of explaining the relationship between researchers and those
participating in the research; b) examine the strengths and weaknesses of each
relationship type and mode; c) point to the complexity and dynamism of the
elements underlying relationships; d) open way of inquiry that can help deepen
our understanding about the relational aspects involved in the social
construction of knowledg
Is there an association between sleep disorders and diabetic foot? A scoping review
Diabetic foot is associated with a low quality of life since physical disabilities, mood
disturbances and psychological disorders are frequent. One of the most important biological processes
to ensure quality of life is sleep. Sleep disorders can impair glycemic control in patients with
diabetes mellitus or even cause long-term type 2 diabetes mellitus. The aim of this study is to
carry out a scoping review about the association between sleep cycle disorders and diabetic foot.
PubMed, Scopus, CINAHL, PEDro, Cochrane Library, SCIELO and EMBASE databases were chosen
for the search and the following terms were used: “diabetic foot”,“sleep*”,“rest-activity”,“mood”
and“behavior”. All the studies should include outcome variables about sleep and diabetic foot.
Finally, 12 articles were selected, all of whichwere observational. The most frequent variables were
those regarding diabetic foot ulcer aspects and diabetic neuropathy on one side, and obstructive
sleep apnea, sleep duration and sleep quality on the other side. The results suggest that there is a
possible association between obstructive sleep apnea and the presence or history of diabetic foot
ulcers. No direct associations between sleep quality or sleep duration and diabetic foot or diabetic
foot ulcer variables have been found
New insights into oxygen surface coverage and the resulting two-component structure of graphene oxide
Elucidating the essential details of the structure of graphene oxide (GO) is still a challenge. There is no consensus in the increasingly abundant literature, especially relating to the epoxy groups as the main surface complexes in the basal plane, as well as the simultaneous presence of GO sheets and oxidative debris (OD), with a large difference in their oxygen content. In the present work we characterized the base-washed GO (bwGO) sheets, the OD and the humic fraction of the OD obtained by base digestion, when the parent GO was dispersed by applying sonication, a routine procedure when starting from dried graphite oxide. When sonication is not applied, the amount of OD detected is considerably lower, indicative of its formation before base digestion. The presence of lactols and carboxylic anhydrides as the dominant surface complexes at graphene edges is consistent with all the characterization results, as well as with the general knowledge of surface chemistry of carbon materials ranging from coal to graphite. These findings suggest that the Hummers-Offeman reaction produces a chemical scissor effect during the water/hydrogen peroxide quenching step, yielding a broad size distribution of GO sheets, with little in-plane oxidation and the vast majority of edges being oxidized to form oxepinone-type functionalities.The authors gratefully acknowledge the financial support of the Ministerio de Economía y Competitividad of Spain (Project CTQ2013-44213-R), and Generalitat Valenciana (project PROMETEOII/2014/007). LRR is grateful for the support of CONICYT-Chile (project Fondecyt 1160949)
Paving the way for adequate myelination: The contribution of galectin-3, transferrin and iron
AbstractConsidering the worldwide incidence of well characterized demyelinating disorders such as Multiple Sclerosis (MS) and the increasing number of pathologies recently found to involve hypomyelinating factors such as micronutrient deficits, elucidating the molecular basis of central nervous system (CNS) demyelination, remyelination and hypomyelination becomes essential to the development of future neuroregenerative therapies. In this context, this review discusses novel findings on the contribution of galectin-3 (Gal-3), transferrin (Tf) and iron to the processes of myelination and remyelination and their potentially positive regulation of oligodendroglial precursor cell (OPC) differentiation. Studies were conducted in cuprizone (CPZ)-induced demyelination and iron deficiency (ID)-induced hypomyelination, and the participation of glial and neural stem cells (NSC) in the remyelination process was evaluated by means of both in vivo and in vitro assays on primary cell cultures
Seudomicetoma dermatofítico en un gato persa : aspectos clínicos, patológicos y evolutivos
En este trabajo presentamos los aspectos clínicos, anatomopatológicos y evolutivos de un caso de dermatitis piogranulomatosa múltiple causada por hongos del género Microsporum, también conocida como seudomicetoma dermatofítico, en un gato persa, no castrado, de un año de edad al comienzo de la enfermedad. Las lesiones se caracterizaron macroscópicamente por la formación de numerosos nódulos de diferentes tamaños, localizados en la cabeza y antebrazo derecho, extendiéndose posteriormente a zona dorso lateral del tronco. La evolución de estos nódulos, que se generalizaron en algo menos de un mes, era hacia la coalescencia y fistulización, con descarga de un material grumoso blanco-grisáceo. El estudio histopatológico reveló una dermatitis piogranulomatosa, supeficial y profunda, caracterizada por presentar en el centro de los granulomas agregados de hongos septados inmersos en una matriz acidófila. La extirpación quirúrgica de un gran número de nódulos proporcionó mejorías transitorias, aunque reaparecieron nuevas lesiones. En este trabajo se describe la evolución tras dos años de seguimiento clínico. Tras el tratamiento con griseofulvina no se detectan nuevas lesiones después de 6 meses de su aplicación y seguimiento.This paper reports the clinical and histopathological features of a case of pyogranulomatous dermatitis caused by Microsporum fungi, a condition also known as dermatophyte pseudomycetoma, in a eneyear-old Persian cat. Grossly apparent fistulized nodules of varying sizes displaying a granular discharge were localized on the head, back, elbow and tail. Microscopic analysis revealed a deep piogranulomatous dermatitis characterized by centrally-located clusters of fungi within an acidophilic matrix. In just under a month, nodules had beco me generalized. Partial surgical excision and non-specific treatment provided temporary improvement, but new lesions subsequentlyappeared
A Mixed Heterobimetallic Y/Eu-MOF for the Cyanosilylation and Hydroboration of Carbonyls
Supplementary Materials
The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/catal12030299/s1. Table S1: Elemental analysis of compounds Y/Eu-MOF. Table S2: ICP-AES results of compound Y/Eu-MOF. Table S3: Crystallographic data and structure refinement details of compound Y/Eu-MOF. Table S4: Selected bond lengths (Å) and angles (°) for compound Y/Eu-MOF. Table S5: Table of the continuous Shape Measurements for the MN3O6 coordination environment. Table S6: Table of the continuous Shape Measurements for the MO8 coordination environment. Table S7: Electrophoretic mobility and ζ-potential dependence, with the pH of the Y/Eu-MOFs particles dispersed in water. Conductivity fixed at 330 µS/cm. Table S8: Optimization of the reaction conditions in the hydroboration reaction. Table S9: Green metrics calculated for Y/Eu-MOF catalyst. Table S10: Catalytic cyanosilylation of benzaldehyde performances of Ln-MOFs, as reported in the literature. Figure S1: Figure of the pattern matching analysis and experimental PXRD for Y/Eu-MOF. Figure S2: Figure of the infrared spectra of the ligand and Y/Eu-MOF. Figure S3: SEM and EDS mapping of bulk material of Y/Eu-MOF. Figure S4: Images and particle size distribution (an overall of 250 particles) in the deposited fraction of Y/Eu-MOF catalyst non-suspended in water (about a 68% of the total amount), determined from optical microscope images. Figure S5: Images and particle size distribution (an overall of 250 particles) of Y/Eu-MOF crystals in the fraction steadily suspended in water (about a 32% of the total amount), determined from optical microscope images. Figure S6: Comparation of the particle size distribution of Y/Eu-MOF in the fraction steadily suspended in water and the non-suspended, determined from optical microscope images. Figure S7: Calibration line of conductivity (µS/cm) vs [NaCl] (mol/L). Figure S8: ζ-potential (mV) dependence with the pH of the Y/Eu-MOF. All the measurements were performed with constant conductivity of 330 µS/cm. Figure S9: Electrophoretic mobility (µm·cm/V·s) dependence with the pH of the Y/Eu-MOF. All the measurements were performed with constant conductivity of 330 µS/cm. Figure S10: Study of the recyclability of Y/Eu-MOF (0.5 mol%) catalyst on the cyanosilylation and hydroboration reaction of acetophenone as carbonyl substrate. Figure S11: Analysis of the TOF (h−1) obtained in the cyanosilylation reaction of acetophenone at different times of reaction with Y/Eu-MOF (0.5 mol%), with the optimized reaction conditions. Figure S12: Analysis of the TOF (h−1) obtained in the hydroboration reaction acetophenone at different times of reaction with Y/Eu-MOF (0.5 mol%), with the optimized reaction conditions. Scheme S1: Reaction conditions used for the study of recyclability of Y/Eu-MOF catalysts in the cyanosilylation reaction. Scheme S2: Reaction conditions used for the study of recyclability of Y/Eu-MOF catalysts in the hydroboration reaction. Scheme S3: Leaching test, carried out after the first and second cycles.Funding: This research has been funded by the State Research Agency (grants CTQ2017-84334-R
and PGC2018-102052-B-C21) of the Spanish Ministry of Science, Innovation and Universities, the
European Union (European Regional Development Fund—ERDF), Junta de Andalucía (P20_01041,
UAL2020-AGR-B1781, B-FQM-734-UGR20 and FQM-394). E.E., S.R., and J.P. acknowledge the
Government of the Basque Country, Juan de la Cierva Incorporación (grant no. IJC2019-038894-I) and
University of Almeria (grant no. HIPATIA2021_04) for their respective fellowsHerein, to the best of our knowledge, the first heterobimetallic Y/Eu porous metal–organic framework (MOF), based on 3-amino-4-hydroxybenzoic acid (H2L) ligand, with the following formulae {[Y3.5Eu1.5L6(OH)3(H2O)3]·12DMF}n (in advance, namely Y/Eu-MOF), is described. The three-dimensional structure has been synthesized by solvothermal routes and thoroughly characterized, by means of single crystal X-ray diffraction, powder X-ray diffraction, electronic microscopy, ICP-AES, electrophoretic mobility, and FTIR spectra. Intriguingly, the porous nature allows for coordinated solvent molecules displacement, yielding unsaturated metal centers, which can act as a Lewis acid catalyst. This novel supramolecular entity has been tested in cyanosilylation and hydroboration reactions on carbonyl substrates of a diverse nature, exhibiting an extraordinary activity.Cierva Incorporación IJC2019-038894-IState Research Agency
CTQ2017-84334-R, PGC2018-102052-B-C21University of Almeria
HIPATIA2021_04Ministerio de Ciencia, Innovación y UniversidadesEuropean CommissionEuropean Regional Development FundJunta de Andalucía
B-FQM-734-UGR20, FQM-394, IJC2019-038894-I, P20_01041, UAL2020-AGR-B178
Structural and magnetic properties study of nd16fe76-xnixb8 alloys with low ni contents
In this work we report a magnetic and structural study of Nd16Fe76-xNixB8 (x = 0, 2.5, 5, 7.5 and 10) alloys. This system was investigated by means of x-ray diffraction, Mössbauer spectrometry, and magnetization. The samples were melted in an arc furnace and then annealed during three days at 1000 oC. The results show the majority formation of the hard Nd2Fe14B tetragonal phase with lattice parameters a = 8.810 Å and c = 12.210 Å; these parameters do not vary substantially with the addition of Ni. Mössbauer results show a ferromagnetic contribution with six sites of iron associated to the Nd2Fe14B phase and a paramagnetic contribution as a doublet attributed to the Nd1,1Fe4B4 phase. The hysteresis cycles show that all the samples present a hard magnetic behavior, and the addition of Ni decreases this property.En este trabajo reportamos las propiedades magnéticas y estructurales de las aleaciones Nd16Fe76-xNixB8 (x=0, 2.5, 5, 7.5 y 10). Este sistema fue investigado por medio de difracción de rayos-x, espectrometría Mössbauer y magnetización. Las muestras fueron fundidas en un horno a arco y luego recocidas a 1000 oC durante tres días. Los resultados muestran la formación mayoritaria de la fase tetragonal dura Nd2Fe14B con parámetros de red a=8.810 Å y c=12.210 Å; estos parámetros no varían sustancialmente al agregar Ni. Los resultados Mössbauer muestran una contribución ferromagnética constituida por seis sitios de hierro asociados a la fase Nd2Fe14B y una contribución paramagnética en forma de doblete atribuida a la fase Nd1,1Fe4B4. Los ciclos de histéresis muestran que todas las muestras presentan un comportamiento magnético duro, y al agregar Ni esta propiedad disminuye
Metal−Organic Frameworks Based on a Janus-Head Biquinoline Ligand as Catalysts in the Transformation of Carbonyl Compounds into Cyanohydrins and Alcohols
A new family of metal−organic frameworks (MOFs)
named GR-MOFs with the chemical formula {[Mx(BCA)y]-
(H2O)z(DMF)w} (x,y,z,w: 1,1,2,0; 1,1.5,0,1; 1,2,2,1; and 1,1,0,2
for GR-MOF-11 to 14, respectively) based on s-block [M: Sr (GRMOF-
11), Ba (GR-MOF-14)] and d-block [M: Y (GR-MOF-12)
and Cd (GR-MOF-13)] metals together with the biquinoline
ligand 2,2′-bicinchoninic acid (H2BCA) has been synthetized by a
solvothermal route and fully characterized by elemental and
thermogravimetric analysis, Fourier transform infrared spectroscopy,
photoluminescence, particle size distribution through optical
microscopy, electrophoretic mobility, and finally, X-ray singlecrystal
and powder diffraction. The structural characterization
reveals that these 2D and 3D MOFs possess a rich variety of
coordination modes that maintained the Janus-head topology on the ligand in most of the cases. The new MOFs were studied in the
catalyzed cyanosilylation and hydroboration of an extensive group of aldehydes and ketones, wherein the s-block metal-based MOFs
GR-MOF-11 and GR-MOF-14 provided the highest efficiency ever reported in the MOF-catalyzed cyanosilylation of carbonyl
compounds by using only 0.5 mol % of catalyst loading, room temperature, and solvent-free conditions. Furthermore, the
hydroboration of ketones has been reported for the first time with this type of s-block metal catalysts obtaining from moderate to
good conversions.MCIN/AEI CTQ2017-84334 R
PGC2018-102052 B-C21
PGC2018-102052 A-C22ERDF A way of making EuropeJunta de Andalucia 102C2000004
CV20-78799
P20_01041UAL-FEDER UAL2020-AGR-B1781FEDER 2014-2020 A-RNM-433-UGR18ProyExcel_00386
ProyExcel_00105B-FQM-734-UGR20
FQM-376
FQM-394Basque Government IT1755-22
IT1500-22Gobierno de Espana MCIN/AEI PDC2021-121248-I00
PLEC2021-007774Juan de la Cierva Incorporacion Fellowship IJC2019-038894-IHipatia fellowship (University of Almeria)Universidad de Granada/CBU
Manganese(I)-Catalyzed H-P Bond Activation via Metal-Ligand Cooperation
Here we report that chiral Mn(I) complexes are capable of H-P bond activation. This activation mode enables a general method for the hydrophosphination of internal and terminal α,β-unsaturated nitriles. Metal-ligand cooperation, a strategy previously not considered for catalytic H-P bond activation, is at the base of the mechanistic action of the Mn(I)-based catalyst. Our computational studies support a stepwise mechanism for the hydrophosphination and provide insight into the origin of the enantioselectivity
Detoxification of azo dyes by a novel pH-versatile, salt-resistant laccase from Streptomyces ipomoea
A newly identified extracellular laccase produced by Streptomyces ipomoea CECT 3341 (SilA) was cloned and
overexpressed, and its physicochemical characteristics assessed together with its capability to decolorize and detoxify an azotype
dye. Molecular analysis of the deduced sequence revealed that SilA contains a TAT-type signal peptide at the N-terminus
and only two cupredoxine domains; this is consistent with reports describing two other Streptomyces laccases but contrasts
with most laccases, which contain three cupredoxine domains. The heterologous expression and purification of SilA
revealed that the homodimer is the only active form of the enzyme. Its stability at high pH and temperature, together with its
resistance to high concentrations of NaCl and to typical laccase inhibitors such as sodium azide confirmed the unique properties
of this novel laccase. The range of substrates that SilA is able to oxidize was found to be pH-dependent; at alkaline pH,
SilA oxidized a wide range of phenolic compounds, including the syringyl and guayacil moieties derived from lignin. The
oxidative potential of this enzyme to use phenolic compounds as natural redox mediators was shown through the coordinated
action of SilA and acetosyringone (as mediator), which resulted in the complete detoxification of the azo-type dye Orange II.This work was financially supported by the
Spanish Ministry of Science (CICYT Project CTQ2004-0344/PPQ to MEA
and BFU 2006-00972/BMC to JMD). We thank the Autonomous Government
of Madrid and the University of Alcalá for the fellowship awarded to
R.M
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