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1.
Rehabilitación (Madr., Ed. impr.) ; 56(3): 226-236, Jul - Sep 2022. graf
Artigo em Espanhol | IBECS | ID: ibc-204913

RESUMO

El objetivo principal del estudio es analizar la evolución científica del campo de investigación de la fibromialgia y la biomecánica. Para ello, se llevó a cabo una búsqueda en Web of Science, desde 1985 hasta 2021, con cuyos resultados se creó un mapa bibliométrico de palabras clave con VOSviewer. También se realizó un de mapeo científico y análisis del rendimiento mediante SciMAT. Se analizaron 233 artículos de todo el mundo, destacando la producción de EE. UU. y España. Los resultados muestran una gran diversidad temática con 54 temáticas diferentes y 33 palabras clave. Si bien la mayoría de temas no están muy desarrollados salvo la actividad física y la sintomatología. En conclusión, el estudio de la fibromialgia y la biomecánica ha crecido de forma general a lo largo del tiempo.(AU)


The main objective of the study is to analyse the scientific evolution of the research field of fibromyalgia and biomechanics. A search was carried out in Web of Science, from 1985 to 2021. With those results, a bibliometric map of keywords was created with VOSviewer. On top of that, scientific mapping and performance analysis were also conducted using SciMAT. A total of 233 articles from around the world were analysed, highlighting the production of the USA and Spain. The results show great diversity in topics with 54 different topics and 33 keywords. Although most of the topics found are not widely developed except the topics of physical activity and symptomatology. In conclusion, the study of fibromyalgia and biomechanics has generally grown over time.(AU)


Assuntos
Humanos , Masculino , Feminino , 50088 , Bibliometria , Fibromialgia , Biologia de Sistemas , Dor Crônica , Dor Musculoesquelética , Manejo da Dor , Medicina Física e Reabilitação
2.
Rehabilitacion (Madr) ; 56(3): 226-236, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-35523619

RESUMO

The main objective of the study is to analyse the scientific evolution of the research field of fibromyalgia and biomechanics. A search was carried out in Web of Science, from 1985 to 2021. With those results, a bibliometric map of keywords was created with VOSviewer. On top of that, scientific mapping and performance analysis were also conducted using SciMAT. A total of 233 articles from around the world were analysed, highlighting the production of the USA and Spain. The results show great diversity in topics with 54 different topics and 33 keywords. Although most of the topics found are not widely developed except the topics of physical activity and symptomatology. In conclusion, the study of fibromyalgia and biomechanics has generally grown over time.


Assuntos
Fibromialgia , Bibliometria , Fenômenos Biomecânicos , Humanos , Espanha
9.
RSC Adv ; 9(31): 17571-17580, 2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-35520560

RESUMO

The purpose of this work is to fabricate self-assembled microstructures by the sol-gel method and study the morphological, structural and compositional dependence of ε-Fe2O3 nanoparticles embedded in silica when glycerol (GLY) and cetyl-trimethylammonium bromide (CTAB) are added as steric agents simultaneously. The combined action of a polyalcohol and a surfactant significantly modifies the morphology of the sample giving rise to a different microstructure in each of the studied cases (1, 3 and 7 days of magnetic stirring time). This is due to the fact that the addition of these two compounds leads to a considerable increase in gelation time as GLY can interact with the alkoxide group on the surface of the iron oxide precursor micelle and/or be incorporated into the hydrophilic chains of CTAB. This last effect causes the iron oxide precursor micelles to be interconnected forming aggregates whose size and structure depend on the magnetic stirring time of the sol-gel synthetic route. In this paper, crystalline structure, composition, purity and morphology of the sol-gel coatings densified at 960 °C are examined. Emphasis is placed on the nominal percentage of the different iron oxides found in the samples and on the morphological and structural differences. This work implies the possibility of patterning ε-Fe2O3 nanoparticles in coatings and controlling their purity by an easy one-pot sol-gel method.

10.
J Phys Condens Matter ; 29(48): 485701, 2017 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-29116941

RESUMO

The current study unveils the structural origin of the magnetic transition of the ε-Fe2O3 polymorph from an incommensurate magnetic order to a collinear ferrimagnetic state at low temperature. The high crystallinity of the samples and the absence of other iron oxide polymorphs have allowed us to carry out temperature-dependent x-ray absorption fine structure spectroscopy experiments out. The deformation of the structure is followed by the Debye-Waller factor for each selected Fe-O and Fe-Fe sub-shell. For nanoparticle sizes between 7 and 15 nm, the structural distortions between the Fete and Fe-D1oc sites are localized in a temperature range before the magnetic transition starts. On the contrary, the inherent interaction between the other sub-shells (named Fe-O1,2 and Fe-Fe1) provokes cooperative magneto-structural changes in the same temperature range. This means that the Fete with Fe-D1oc polyhedron interaction seems to be uncoupled with temperature dealing with these nanoparticle sizes wherein the structural distortions are likely moderate due to surface effects.

11.
Appl Biochem Biotechnol ; 182(4): 1619-1629, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28155169

RESUMO

Many different materials have been tested for ß-glucosidases immobilization. Such materials, however, often show a poor activity related to a low surface area of the support or even enzyme hindrance caused by entrapment inside porous matrix. In this context, the use of nanosized zeolites as enzymes support is quite new and may be an interesting alternative. The present work evaluates the immobilization of ß-glucosidases in nanosized silicalites by covalent coupling. The new biocatalyst was able to convert 100% of cellobiose into glucose in 18 h at 50 °C and pH 5, retaining 85% of its activity after five cycles of reuse. A detailed investigation of the published literature indicates that, apparently, this is the first work concerning the immobilization of ß-glucosidases on nanosized zeolites ever reported.


Assuntos
Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Nanoestruturas/química , Silicatos/química , beta-Glucosidase/química , beta-Glucosidase/metabolismo , Biocatálise , Hidrólise , Propriedades de Superfície
12.
Food Chem ; 213: 169-179, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27451169

RESUMO

A collaborative trial was conducted to determine the performance characteristics of an analytical method for the quantification of inorganic arsenic (iAs) in food. The method is based on (i) solubilisation of the protein matrix with concentrated hydrochloric acid to denature proteins and allow the release of all arsenic species into solution, and (ii) subsequent extraction of the inorganic arsenic present in the acid medium using chloroform followed by back-extraction to acidic medium. The final detection and quantification is done by flow injection hydride generation atomic absorption spectrometry (FI-HG-AAS). The seven test items used in this exercise were reference materials covering a broad range of matrices: mussels, cabbage, seaweed (hijiki), fish protein, rice, wheat, mushrooms, with concentrations ranging from 0.074 to 7.55mgkg(-1). The relative standard deviation for repeatability (RSDr) ranged from 4.1 to 10.3%, while the relative standard deviation for reproducibility (RSDR) ranged from 6.1 to 22.8%.


Assuntos
Arsênio/análise , Contaminação de Alimentos/análise , Espectrofotometria Atômica , Agaricales/química , Animais , Bivalves/química , Brassica/química , Proteínas de Peixes/química , Análise de Alimentos , Oryza/química , Reprodutibilidade dos Testes , Alga Marinha/química , Triticum/química
13.
J Food Sci Technol ; 53(12): 4298-4307, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28115770

RESUMO

The aim of this work was to assess the effects of temperature (T), time (t) and pH treatments and an in vitro digestion on the stability of the angiotensin I-converting-enzyme-inhibitory activity (ACEIA) and antithrombotic activity (ATA; assessed as inhibition of platelet aggregation) of selected protein hydrolysates of amaranth named Alb1H103 and GloH88 and GluH24 with dipeptidyl peptidase IV inhibitory activity (DPPIVIA). Heat treatment (40-100 °C) for 1 h showed no significant differences among ACEIA, DPPIVIA and ATA of the heated hydrolysates at pH 4 and 7. There was no statistically significant loss of any bioactivity under heat treatment for 3 h at pH 4.0. Alb1H103 and GluH24 maintained the inhibitory activity of ACE and ATA at pH 7.0 for 3 h, whereas GloH88 maintained ACEIA and ATA for 2.0 h at pH 7.0. The pH effect on hydrolysates bioactivity was assessed in the range of 2.0-12.0. This was negligible on ACEIA, ATA and DPPIVIA. The in vitro digestion was performed using pepsin, trypsin (T) and α-chymotrypsin (C). A previous treatment of hydrolysates with pepsin improved the proteolytic activities of T and C. The hydrolysates kept at 100 °C for 1 h at pH 4.0, showed a significant increase in bioactivity. Conversely, a treatment at pH 7.0 showed no significant difference (p < 0.05) in the hydrolysates bioactivities after their digestion. Thus, biological activity of hydrolysates may be preserved or enhanced, depending on their processing conditions.

14.
Food Chem ; 181: 304-9, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25794754

RESUMO

The bioaccessible selenium species from cabbage were studied using an in vitro physiologically-based extraction test (PBET) which establishes conditions that simulate the gastric and gastrointestinal phases of human digestion. Samples of cabbage (Brassica oleracea) grown in peat fortified with different concentrations of Se(IV) and Se(VI) were analysed, and several enzymes (pepsin, pancreatin and amylase) were used in the PBET. The effect of boiling before extraction was also assayed. Selenium speciation in the PBET extracts was determined using anionic exchange and LC-ICP/MS. The selenocompounds in the extracts were Se(IV), SeMet and, mostly, Se(VI) species. The results show that the activity of the enzymes increased the concentration of the selenocompounds slightly, although the use of amylase had no effect on the results. The PBET showed the concentration of inorganic selenium in the extracts from boiled cabbage decreased as much as 4-fold while the release of SeMet and its concentration increased (up to 6-fold), with respect to raw cabbage.


Assuntos
Brassica/química , Culinária/métodos , Selênio/análise , Amilases/metabolismo , Cromatografia Líquida , Espectrometria de Massas , Pancreatina/metabolismo , Pepsina A/metabolismo , Selenometionina/análise , Solo
15.
Nat Commun ; 6: 6147, 2015 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-25707936

RESUMO

A plethora of technological applications justify why titanium dioxide is probably the most studied oxide, and an optimal exploitation of its properties quite frequently requires a controlled modification of the surface. Low-energy ion bombardment is one of the most extended techniques for this purpose and has been recently used in titanium oxides, among other applications, to favour resistive switching mechanisms or to form transparent conductive layers. Surfaces modified in this way are frequently described as reduced and defective, with a high density of oxygen vacancies. Here we show, at variance with this view, that high ion doses on rutile titanium dioxide (110) induce its transformation into a nanometric and single-crystalline titanium monoxide (001) thin film with rocksalt structure. The discovery of this ability may pave the way to new technical applications of ion bombardment not previously reported, which can be used to fabricate heterostructures and interfaces.

16.
Scanning ; 37(3): 165-71, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25676058

RESUMO

The bimetallic nickel-tungsten catalysts were prepared via solvothermal method. The X-ray Diffractometer (XRD) analysis revealed that the corresponding peaks at 14°, 34°, and 58° were for tungsten disulfide (WS2 ) hexagonal phase. The catalysts displayed different crystalline phase with nickel addition, and as an effect the WS2 surface area decreased from 74.7 to 2.0 m(2) g(--1) . In this sense, high-resolution transmission electron microscopy (HRTEM) showed the layers set in direction (002) with an onion-like morphology, and in the center of the particles there is a large amount of nickel contained with 6-8 layers covering it. The catalytic dehydration of 2-propanol was selective to propene in 100% at 250 °C for the sample with 0.7 of atomic ratio of Ni/Ni + W.

17.
Food Chem ; 166: 544-550, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25053092

RESUMO

The influence of storage time and temperature on Sb migration from PET bottles into mineral water was studied in short-term tests lasting up to 15 days and long-term studies lasting up to 220 days. Samples purchased were stored in three different coloured bottles: clear (CL), light blue (LB) and dark blue (DB). Sb migration was assayed by HG-AFS for total determination and HPLC-ICP-MS for speciation analysis. Migration studies showed that waters stored at 4 and 20 °C were not subject to Sb migration. At 40 °C there was a significant increase in Sb concentration, although the maximum limit established by the European Union (5.0 µgL(-)(1)) was not exceeded, whereas at 60 °C samples were subject to considerable Sb migration after 30 days of storage. In this case, the maximum limit established by the European Union was exceeded and both Sb (V) and Sb (III) were detected.


Assuntos
Antimônio/análise , Água Potável/análise , Contaminação de Alimentos/análise , Embalagem de Alimentos , Águas Minerais/análise , Polietilenotereftalatos/química , Cromatografia Líquida de Alta Pressão , União Europeia , Armazenamento de Alimentos/métodos , Espectrometria de Massas , Temperatura
18.
Artigo em Inglês | MEDLINE | ID: mdl-25365736

RESUMO

The Institute for Reference Materials and Measurements (IRMM) of the Joint Research Centre (JRC), a Directorate General of the European Commission, operates the International Measurement Evaluation Program (IMEP). IMEP organises inter-laboratory comparisons in support of European Union policies. This paper presents the results of two proficiency tests (PTs): IMEP-116 and IMEP-39, organised for the determination of total Cd, Pb, As, Hg and inorganic As (iAs) in mushrooms. Participation in IMEP-116 was restricted to National Reference Laboratories (NRLs) officially appointed by national authorities in European Union member states. IMEP-39 was open to all other laboratories wishing to participate. Thirty-seven participants from 25 countries reported results in IMEP-116, and 62 laboratories from 36 countries reported for the IMEP-39 study. Both PTs were organised in support to Regulation (EC) No. 1881/2006, which sets the maximum levels for certain contaminants in food. The test item used in both PTs was a blend of mushrooms of the variety shiitake (Lentinula edodes). Five laboratories, with demonstrated measurement capability in the field, provided results to establish the assigned values (Xref). The standard uncertainties associated to the assigned values (uref) were calculated by combining the uncertainty of the characterisation (uchar) with a contribution for homogeneity (ubb) and for stability (ust), whilst uchar was calculated following ISO 13528. Laboratory results were rated with z- and zeta (ζ)-scores in accordance with ISO 13528. The standard deviation for proficiency assessment, σp, ranged from 10% to 20% depending on the analyte. The percentage of satisfactory z-scores ranged from 81% (iAs) to 97% (total Cd) in IMEP-116 and from 64% (iAs) to 84% (total Hg) in IMEP-39.


Assuntos
Arsênio/análise , Cádmio/análise , Poluentes Ambientais/análise , Chumbo/análise , Mercúrio/análise , Cogumelos Shiitake/química , União Europeia , Contaminação de Alimentos/análise , Humanos , Ensaio de Proficiência Laboratorial/legislação & jurisprudência , Ensaio de Proficiência Laboratorial/estatística & dados numéricos , Variações Dependentes do Observador , Guias de Prática Clínica como Assunto , Reprodutibilidade dos Testes
19.
Faraday Discuss ; 152: 63-86; discussion 99-120, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22455039

RESUMO

In this study, a systematic series of AuPd bimetallic particles were prepared by colloidal synthesis methods, in order to gain better control over the particle size distribution and structure. Particles having random alloy structures, as well as 'designer' particles with Pd-shell/Au-core and Au-shell/Pd-core morphologies, have been prepared and immobilized on both activated carbon and TiO2 supports. Aberration corrected analytical electron microscopy (ACEAM) has been extensively used to characterize these sol-immobilized materials. In particular, state-of-the-art z-contrast STEM-HAADF imaging and STEM-XEDS spectrum imaging has been employed. These techniques have provided invaluable new (and often unexpected) information on the atomic structure, elemental distribution within particles, and compositional variations between particles for these controlled catalyst preparations. In addition, we have been able to compare their differing thermal stability, sintering and wetting behaviors on activated carbon and TiO2 supports. These sol immobilized materials have also been compared as catalysts for (i) benzyl alcohol oxidation and (ii) the direct production of H2O2 in an attempt to elucidate the optimum particle morphology/ support combination for each reaction.

20.
Artigo em Inglês | MEDLINE | ID: mdl-19651231

RESUMO

The Pacific lion's paw scallop Nodipecten subnodosus has been one of the most important commercial species of mollusc in the Baja California peninsula in Mexico since 1990. This species is a functional hermaphrodite with tropical and sub-tropical distributions and experiences wide annual temperature oscillations influencing its physiological functions. We determined norepinephrine (NE), dopamine (DA), and serotonin (5-HT) concentrations in different organs (female and male gonads, digestive gland, adductor muscle, gill, mantle, and foot) of N. subnodosus, at 6 reproductive stages (resting, initial, maturing, mature, partially spent and fully spent). Monoamine concentrations were determined by HPLC fitted with an electrochemical detector. Results indicated that monoamine concentrations increased during maturing stage, peaked at mature stage and declined after spawning. NE concentrations were higher than the rest of monoamines followed by DA, and 5-HT. NE was present in all organs at all reproductive stages. DA concentrations were higher in the gill and digestive gland during all stages. 5-HT was only detectable in the male gonadic portion at all stages except at spent stage. NE was the most abundant neurotransmitter found in the female gonad of N. subnodosus, while 5-HT was the most abundant neurotransmitter found in the male gonad. Furthermore, these two neurotransmitters accumulated in the respective gonad tissues during the initial reproductive stages I to IV and then declined after spawning (stages V and VI). This suggests that this species utilized different neurotransmitters specific for each gender and that this utilization was related to the reproductive cycle.


Assuntos
Dopamina/metabolismo , Norepinefrina/metabolismo , Pectinidae/fisiologia , Serotonina/metabolismo , Animais , Feminino , Masculino , Reprodução/fisiologia , Transmissão Sináptica/fisiologia
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