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1.
Alzheimers Dement (N Y) ; 10(1): e12451, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38505833

RESUMEN

INTRODUCTION: Biomarker-informed criteria were proposed for the diagnosis of Alzheimer's disease (AD) by the National Institute on Aging and the Alzheimer's Association (NIA-AA) in 2011; however, the adequacy of this criteria has not been sufficiently evaluated. METHODS: ReDeMa (Red de Demencias de Madrid) is a regional cohort of patients attending memory and neurology clinics. Core cerebrospinal fluid biomarkers were obtained, NIA-AA diagnostic criteria were considered, and changes in diagnosis and management were evaluated. RESULTS: A total of 233 patients were analyzed (mean age 70 years, 50% women, 73% AD). The diagnostic language was modified significantly, with a majority assumption of NIA-AA definitions (69%). Confidence in diagnosis increased from 70% to 92% (p < 0.0005) and management was changed in 71% of patient/caregivers. The influence of neurologist's age or expertise on study results was minimal. DISCUSSION: The NIA-AA criteria are adequate and utile for usual practice in memory and neurology clinics, improving diagnostic confidence and significantly modifying patient management. HIGHLIGHTS: Alzheimer's disease (AD) cerebrospinal fluid (CSF) biomarkers increase diagnostic certainty regardless of the neurologist.AD CSF biomarkers lead to changes in disease management .Biomarker-enriched, 2011 NIA-AA diagnostic criteria are adequate for usual practice.

2.
J Phys Chem A ; 125(48): 10463-10474, 2021 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-34812636

RESUMEN

Analytical calculation of alchemical derivatives based on auxiliary density perturbation theory is described, coded, and validated. For the case where the nucleus is a hydrogen atom and the nuclear charge is changed from 1 to 0, it turns out that a good estimate of the proton binding energies can be obtained very efficiently. First-order results correspond exactly to the molecular electrostatic potential evaluated at the hydrogen nucleus location (removing self-repulsion), in agreement with previously reported extensive studies. Therefore, the second-order results reported here are refinements in accuracy that finally allow a quantitative exploration of differential acidity. Furthermore, the recently reported h function is produced in its analytical form as a byproduct and local descriptor associated with the proton binding energy values found with this approach. In an example application, proton binding energies are computed for a family of imidazolium derivatives to demonstrate the capabilities and the stability of the method with respect to changes in basis set or exchange-correlation functional.

3.
Med Chem ; 17(1): 33-39, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-31808388

RESUMEN

BACKGROUND: In the therapy of cancer, several treatments have been designed using nanomaterials, among which gold nanoparticles (AuNPs) have been featured as a promising antitumoral agent. Our research group has developed the synthesis of gold nanoparticles L-AuNPs and D-AuNPs stabilized with zwitterions of imidazolium (L-1 and D-1) derived from L-methionine and D-methionine. Because the stabilizer agent is chiral, we observed through circular dichroism that AuNPs also present chirality; such chirality as well as the fact that the stabilizing agent contains fragments of methionine and imidazolium that are commonly involved in biological processes, opens up the possibility that this system may have biological compatibility. Additionally, the presence of methionine in the stabilizing agent opens the application of this system as a possible antitumor agent because methionine is involved in methylation processes of molecules such as DNA. OBJECTIVE: The aim of this research is the evaluation of the antitumor activity of gold nanoparticles stabilized with zwitterions of imidazolium (L-AuNPs) derived from L-methionine in the model of BALB/c mice with lymphoma L5178Y. METHODS: Taking as a parameter cell density, the evaluation of the inhibitory effect of L-AuNPs was carried out with a series of in vivo tests in BALB/c type mice; three groups of five mice each were formed (Groups 1, 2 and 3); all mice were i.p. inoculated with the lymphoblast murine L5178Y. Group 1 consisted of mice without treatment. In the Groups 2 and 3 the mice were treated with L-AuNPs at 0.3 mg/Kg on days 1, 7 and 14 by orally and intraperitonally respectively. RESULTS: These results show low antitumor activity of these gold nanoparticles (L-NPsAu) but interestingly, the imidazolium stabilizing agent of gold nanoparticle (L-1) displayed promising antitumor activity. On the other hand, the enantiomer of L-1, (D-1) as well as asymmetric imidazole derivate from L-methionine (L-2), do not exhibit the same activity as L-1. CONCLUSION: The imidazolium stabilizing agent (L-1) displayed promising antitumor activity. Modifications in the structure of L-1 showed that, the stereochemistry (like D-1) and the presence of methionine fragments (like L-2) are determinants in the antitumor activity of this compound.


Asunto(s)
Imidazoles/química , Imidazoles/farmacología , Linfoma/patología , Metionina/química , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Oro/química , Imidazoles/uso terapéutico , Linfoma/tratamiento farmacológico , Nanopartículas del Metal/química , Metilación , Ratones Endogámicos BALB C
4.
Clin Neuropsychol ; 34(sup1): 13-28, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-31757190

RESUMEN

OBJECTIVE: The aim of this study was to establish reliable change and regression-based change score norms on the 37-item version of MMSE in older Spanish adults at the three-year follow-up. METHOD: All subjects of this research were selected from the Neurological Disorders in Central Spain (NEDICES), a prospective population-based cohort study of older adults (65 years and over). Of the 4208 individuals free from neurological disorders in this cohort, 2073 participants completed the MMSE-37 at baseline and at the three-year follow-up. Reliable Change Indices were computed for the 80, 90% and 95 confidence intervals (CIs). Multiple regression analyses were used to derive equations for predicting MMSE-37 post-test scores taking into account baseline scores, time to follow-up and sociodemographic factors. RESULTS: The MMSE-37 obtained a marginal test-retest reliability (.70). The results showed significant effects of education, age, and sex on the MMSE-37 change scores. After correcting for regression to the mean, at least a 6-point change on MMSE-37 (three-years follow-up) is required to be classified as reliable (90% CI). CONCLUSIONS: These findings demonstrate that the MMSE-37 is a reliable test-retest measure whose change scores are significantly influenced by sociodemographic factors. Importantly, small changes on this measure require a cautious interpretation.


Asunto(s)
Trastornos del Conocimiento/diagnóstico , Pruebas Neuropsicológicas/normas , Anciano , Estudios de Cohortes , Femenino , Humanos , Masculino , Estudios Prospectivos , Reproducibilidad de los Resultados , España
5.
Sci Rep ; 9(1): 19327, 2019 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-31852938

RESUMEN

Nowadays, there are several approaches reported to accomplish the green synthesis of metal nanoparticles by using bacterial and fungi supernatants or by-products generated by these microorganisms. Therefore, agars as solely reductive regents have started to be used in order to obtain metal nanoparticles. This paper shows the results of the synthesis of gold and silver nanoparticles with different morphology, mainly triangular and truncated triangular, using Eosin Methylene Blue (EMB) agar as reducing agent. To control the reaction process, the necessary activation energy for the reducer was provided by three different techniques: microwave radiation, using a domestic microwave oven, ultraviolet radiation, and heating on a conventional plate. The evolution of the reduction process and stability of the samples was performed by ultraviolet visible spectroscopy. Morphology was carefully analyzed using high-resolution transmission electron microscopy (HRTEM) and Transmission electron microscopy (TEM). A one step synthesis for gold and silver nanoparticles was optimized with an eco-friendly and economic process.

6.
Arch Gerontol Geriatr ; 80: 88-94, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30391685

RESUMEN

OBJECTIVE: We investigated the mortality rates of three subtypes of disability and their specific explanatory factors in older adults. METHODS: Our data come from NEDICES, a population-based longitudinal cohort study of Spanish older adults. We examined 3816 participants without dementia who completed the Pfeffer's Functional Activities Questionnaire (FAQ) and an assessment of self-perceived functional limitations (SFL) associated with health conditions. Subjects were classified into mutually exclusive subtypes of disability: subtype 1 (SFL), subtype 2 (impaired FAQ), and subtype 3 (impaired FAQ plus SFL). Factors related to all disability subtypes were analyzed using a multinomial logistic regression (MLR), whereas Cox regression (CR) models adjusted by covariates were applied to compare survival rates between groups at the 5-year follow up. RESULTS: The CR models indicated that SFL and FAQ scores were associated with higher risk of mortality at 5-years. After stratifying by subtypes of disability, mortality was significantly higher in subtype 3 than in subtypes 1 and 2. All models were consistent after adjusting by different covariates. The MLR showed that subtype 1 was specifically associated with the number of comorbidities, whereas subtype 2 was associated with lower MMSE scores depression and living in nursing homes. CONCLUSIONS: Our results show that the combination of impaired FAQ plus SFL have an increased differential predictive utility for mortality than approaches based on unique measures. They also indicate that both measures of disability are associated with different explanatory factors.


Asunto(s)
Personas con Discapacidad/estadística & datos numéricos , Actividades Cotidianas , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Modelos Logísticos , Estudios Longitudinales , Masculino , Modelos de Riesgos Proporcionales , Tasa de Supervivencia
7.
Langmuir ; 34(25): 7455-7464, 2018 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-29856927

RESUMEN

The adsorption of concentrated poly(diallyldimethylammonium chloride) (PDADMAC)-sodium lauryl ether sulfate (SLES) mixtures at the water/vapor interface has been studied by different surface tension techniques and dilational viscoelasticity measurements. This work tries to shed light on the way in which the formation of polyelectrolyte-surfactant complexes in the bulk affects the interfacial properties of mixtures formed by a polycation and an oppositely charged surfactant. The results are discussed in terms of a two-step adsorption-equilibration of PDADMAC-SLES complexes at the interface, with the initial stages involving the diffusion of kinetically trapped aggregates formed in the bulk to the interface followed by the dissociation and spreading of such aggregates at the interface. This latter process becomes the main contribution to the surface tension decrease. This work aids our understanding of the most fundamental basis of the physicochemical behavior of concentrated polyelectrolyte-surfactant mixtures which present complex bulk and interfacial interactions with interest in both basic and applied sciences.

8.
Langmuir ; 34(21): 5978-5989, 2018 05 29.
Artículo en Inglés | MEDLINE | ID: mdl-29718671

RESUMEN

The control of the behavior of oil in water emulsions requires deeper investigations on the adsorption properties of the emulsion stabilizers at the interfaces, which are fundamental to explain the (de)stabilization mechanisms. In this work, we present an extensive study on oil-in-water emulsions stabilized by sodium dodecyl sulfate (SDS) below its critical micellar concentration. Dynamic tensiometry, dilational rheology, and electrical conductivity measurements are used to investigate the adsorption properties at the droplet interface, whereas the aging of the respective emulsions was investigated by monitoring the macroscopic thickness of the emulsion layer, by microimaging and dynamic light scattering (DLS) analysis, to get information on the drop size distribution. In addition, the droplet coalescence is investigated by a microscopy setup. The results of this multitechnique study allow deriving a coherent scenario where the adsorption properties of this ionic surfactant relate to those of the emulsion, such as, for example, the prevention of droplet coalescence and the presence of other mechanisms, such as Ostwald ripening, responsible for the emulsion aging.

9.
Phys Chem Chem Phys ; 20(3): 1395-1407, 2018 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-29297520

RESUMEN

Polyelectrolyte-surfactant mixtures and their interactions with fluid interfaces are an important research field due to their use in technological applications. Most of the existing knowledge on these systems is based on models in which the polyelectrolyte concentration is around 50 times lower than that used in commercial formulations. The present work marks a step to close the gap on the understanding of their behavior under more practically-relevant conditions. The adsorption of concentrated mixtures of poly(diallyldimethyl-ammonium) chloride and sodium N-lauroyl-N-methyltaurate at the water/vapor interface with a crude mixing protocol has been studied by different surface tension techniques, Brewster angle microscopy, neutron reflectometry, and several bulk characterization techniques. Kinetically-trapped aggregates formed during mixing influence the interfacial morphology of mixtures produced in the equilibrium one-phase region, yet fluctuations in the surface tension isotherm result depending on the tensiometric technique applied. At low bulk surfactant concentrations, the free surfactant concentration is very low, and the interfacial composition matches the trend of the bulk complexes, which is a behavior that has not been observed in studies on more dilute mixtures. Nevertheless, a transition to synergistic co-adsorption of complexes and free surfactant is observed at the higher bulk surfactant concentrations studied. This transition appears to be a special feature of these more concentrated mixtures, which deserves attention in future studies of systems with additional components.

10.
Dalton Trans ; 46(12): 3809-3811, 2017 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-28234397

RESUMEN

A simple and direct method is described to prepare cationic bis(NHC)-Au(i) complexes containing N-alkyl or N-aryl NHC ligands to generate relevant gold complexes using metallic gold as the starting material.

11.
J Clin Exp Neuropsychol ; 39(2): 112-119, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27484199

RESUMEN

BACKGROUND: The effect of different educational indices on clinical diagnosis of dementia requires more investigation. OBJECTIVE: We compared the differential influence of two educational indices (EIs): years of schooling and level of education (i.e., null/low literacy, can read and write, primary school, and secondary school) on global cognition, functional performance, and the probability of having a dementia diagnosis. METHOD: A total of 3,816 participants were selected from the population-based study of older adults "Neurological Disorders in Central Spain" (NEDICES). The 37-item version of the Mini-Mental State Examination (MMSE-37) and the Pfeffer's questionnaire were applied to assess cognitive and functional performance, respectively. The diagnosis of dementia was performed by expert neurologists according to Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition (DSM-IV) criteria. Logistic regression models adjusted for potential confounders were carried out to test the association between the two EIs and dementia diagnosis. RESULTS: Both EIs were significantly associated with cognitive and functional scores, but individuals with null/low literacy performed significantly worse on MMSE-37 than literates when these groups were compared in terms of years of schooling. The two EIs were also related to an increased probability of dementia diagnosis in logistic models, but the association's strength was stronger for level of education than for years of schooling. CONCLUSION: Literacy predicted cognitive performance over and above the years of schooling. Lower education increases the probability of having a dementia diagnosis but the impact of different EIs is not uniform.


Asunto(s)
Cognición/fisiología , Demencia/diagnóstico , Escolaridad , Alfabetización , Anciano , Anciano de 80 o más Años , Demencia/psicología , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Femenino , Humanos , Masculino , Persona de Mediana Edad , España , Encuestas y Cuestionarios
12.
Beilstein J Nanotechnol ; 7: 197-208, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26977377

RESUMEN

This work addresses the formation and the internal morphology of polyelectrolyte layers obtained by the layer-by-layer method. A multimodal characterization showed the absence of stratification of the films formed by the alternate deposition of poly(diallyldimethylammonium chloride) and poly(sodium 4-styrenesulfonate). Indeed the final organization might be regarded as three-dimensional solid-supported inter-polyelectrolyte films. The growth mechanism of the multilayers, followed using a quartz crystal microbalance, evidences two different growth trends, which show a dependency on the ionic strength due to its influence onto the polymer conformation. The hydration state does not modify the multilayer growth, but it contributes to the total adsorbed mass of the film. The water associated with the polyelectrolyte films leads to their swelling and plastification. The use of X-ray photoelectron spectroscopy has allowed for deeper insights on the internal structure and composition of the polyelectrolyte multilayers.

13.
J Alzheimers Dis ; 50(3): 719-31, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26757038

RESUMEN

BACKGROUND: The predictive value of diverse subtypes of mild cognitive impairment (MCI) for dementia and death is highly variable. OBJECTIVE: To compare the predictive value of several MCI subtypes in progression to dementia and/or mortality in the NEDICES (Neurological Disorders in Central Spain) elderly cohort. METHODS: Retrospect algorithmic MCI subgroups were established in a non-dementia baseline NEDICES cohort using Spanish adaptations of the original Mini-Mental State Examination (MMSE-37) and Pfeffer's Functional Activities Questionnaire (Pfeffer-11). The presence of MCI was defined according two cognitive criteria: using two cut-offs points on the total MMSE-37 score. Five cognitive domains were used to establish the MCI subtypes. Functional capacity (Pfeffer-11) was preserved or minimally impaired in all MCI participants. The incident dementia diagnoses were established by specialists and the mortality data obtained from Spanish official registries. RESULTS: 3,411 participants without dementia were assessed in 1994-5. The baseline prevalence of MCI varied according to the MCI definition (4.3%-31.8%). The follow-up was a mean of 3.2 years (1997-8). The dementia incidence varied between 14.9 and 71.8 per 1,000/person-years. The dementia conversion rate was increased in almost all MCI subgroups (p >  0.01), and mortality rate was raised only in four MCI subtypes. The amnestic-multi-domain MCI (aMd-MCI) had the best dementia predictive accuracy (highest positive likelihood ratio and highest clinical utility when negative). CONCLUSIONS: Those with aMd-MCI were at greatest risk of progression to dementia, as in other surveys and might be explored with increased attention in MCI research and in dementia preventive trials.


Asunto(s)
Disfunción Cognitiva , Demencia/diagnóstico , Anciano , Anciano de 80 o más Años , Algoritmos , Disfunción Cognitiva/clasificación , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/mortalidad , Estudios de Cohortes , Femenino , Humanos , Masculino , Escala del Estado Mental , Pruebas Neuropsicológicas , Valor Predictivo de las Pruebas , Pronóstico , Modelos de Riesgos Proporcionales , España
14.
Adv Colloid Interface Sci ; 233: 38-64, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26608684

RESUMEN

The interest of polymer-surfactant systems has undergone a spectacular development in the last thirty years due to their complex behavior and their importance in different industrial sectors. The importance can be mainly associated with the rich phase behavior of these mixtures that confers a wide range of physico-chemical properties to the complexes formed by polymers and surfactants, both in bulk and at the interfaces. This latter aspect is especially relevant because of the use of their mixture for the stabilization of dispersed systems such as foams and emulsions, with an increasing interest in several fields such as cosmetic, food science or fabrication of controlled drug delivery structures. This review presents a comprehensive analysis of different aspects related to the phase behavior of these mixtures and their intriguing behavior after adsorption at the liquid/air interface. A discussion of some physical properties of the bulk is also included. The discussion clearly points out that much more work is needed for obtaining the necessary insights for designing polymer-surfactant mixtures for specific applications.

15.
ACS Omega ; 1(5): 876-885, 2016 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-31457170

RESUMEN

Gold nanoparticles (AuNPs) stabilized by imidazolium salts derived from amino acids [glycine (1), rac-alanine (2), l-phenylalanine (3), and rac-methionine (4)] were prepared. The AuNPs were stabilized the most by 4, which kept the particles dispersed in water for months at pH > 5.5. These AuNPs exhibited a well-defined absorption band at 517 nm and had an average particle size of 11.21 ± 0.07 nm. The 4-AuNPs were reversibly aggregated by controlling the pH of the solution. Chiral R,R-4-AuNPs and S,S-4-AuNPs were synthesized, and the chiral environment on the nanoparticle surface was confirmed using circular dichroism; these nanoparticles exhibited a molecular recognition of chiral substrates. Furthermore, they showed potential for separating racemic mixtures when supported on a layered double hydroxide.

16.
Adv Colloid Interface Sci ; 222: 461-87, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24954878

RESUMEN

The use of polymer and polymer - surfactant mixtures for designing and developing textile and personal care cosmetic formulations is associated with various physico-chemical aspects, e.g. detergency and conditioning in the case of hair or wool, that determine their correct performances in preserving and improving the appearance and properties of the surface where they are applied. In this work, special attention is paid to the systems combining polycations and negatively charged surfactants. The paper introduces the hair surface and presents a comprehensive review of the adsorption properties of these systems at solid-water interfaces mimicking the negative charge and surface energy of hair. These model surfaces include mixtures of thiols that confer various charge densities to the surface. The kinetics and factors that govern the adsorption are discussed from the angle of those used in shampoos and conditioners developed by the cosmetic industry. Finally, systems able to adsorb onto negatively charged surfaces regardless of the anionic character are presented, opening new ways of depositing conditioning polymers onto keratin substrates such as hair.


Asunto(s)
Cosméticos/química , Electrólitos/química , Polímeros/química , Tensoactivos/química , Adsorción , Humanos , Propiedades de Superficie
17.
J Clin Neurol ; 10(2): 162-5, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24829603

RESUMEN

BACKGROUND: Ocular dipping (OD), or inverse ocular bobbing, consists of slow, spontaneous downward eye movements with rapid return to the primary position. It has been mainly reported following hypoxic-ischemic encephalopathy, but has also been described in association with other types of diffuse or multifocal encephalopathies and structural brainstem damage. CASE REPORT: We report the case of a previously asymptomatic 66-year-old woman who presented with confusion, recent memory disturbances, and abnormal involuntary movements, followed by a coma. Abnormal spontaneous vertical eye movements consistent with OD developed from the fourth day after admission, and the patient died 20 days later. The pathological examination of the brain confirmed the diagnosis of Creutzfeldt-Jakob disease. CONCLUSIONS: The precise location of damage causing OD is unknown. In contrast to ocular bobbing, OD has no localizing value itself, but structural brainstem damage is likely when it appears combined with other spontaneous vertical eye movements.

19.
Clin Neuropharmacol ; 36(4): 133-4, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23783006

RESUMEN

Mirtazapine is an antidepressant with an adequate safety profile used in major depression. Adverse effects have been reported in the field of movement disorders, but none as truncal segmental dystonia (Pisa syndrome). We describe the case of a woman who developed Pisa syndrome after a single dose of mirtazapine.


Asunto(s)
Antidepresivos Tricíclicos/efectos adversos , Discinesia Inducida por Medicamentos/fisiopatología , Distonía/etiología , Mianserina/análogos & derivados , Antidepresivos Tricíclicos/uso terapéutico , Trastorno Depresivo Mayor/tratamiento farmacológico , Femenino , Humanos , Mianserina/efectos adversos , Mianserina/uso terapéutico , Persona de Mediana Edad , Mirtazapina , Cuello , Índice de Severidad de la Enfermedad , Torso
20.
J Colloid Interface Sci ; 400: 49-58, 2013 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-23582902

RESUMEN

Lithium cations are known to form complexes with the oxygen atoms of poly(oxyethylene) chains. The effect of Li(+) on the surface properties of three block-copolymers containing poly(oxyethylene) (PEO) have been studied. Two types of copolymers have been studied, a water soluble one of the pluronic family, PEO-b-PPO-b-PEO, PPO being poly(propyleneoxyde), and two water insoluble ones: PEO-b-PS and PEO-b-PS-b-PEO, PS being polystyrene. In the case of the pluronic the adsorption kinetics, the equilibrium surface tension isotherm and the aqueous/air surface rheology have been measured, while for the two insoluble copolymers only the surface pressure and the surface rheology have been studied. In all the cases two different Li(+) concentrations have been used. As in the absence of lithium ions, the adsorption kinetics of pluronic solutions shows two processes, and becomes faster as [Li(+)] increases. The kinetics is not diffusion controlled. For a given pluronic concentration the equilibrium surface pressure increases with [Li(+)], and the isotherms show two surface phase transitions, though less marked than for [Li(+)]=0. A similar behavior was found for the equilibrium isotherms of PEO-b-PS and PEO-b-PS-b-PEO. The surface elasticity of these two copolymers was found to increase with [Li(+)] over the whole surface concentration and frequency ranges studied. A smaller effect was found in the case of the pluronic solutions. The results of the pluronic solutions were modeled using a recent theory that takes into account that the molecules can be adsorbed at the surface in two different states. The theory gives a good fit for the adsorption kinetics and a reasonably good prediction of the equilibrium isotherms for low and intermediate concentrations of pluronic. However, the theory is not able to reproduce the isotherm for [Li(+)]=0. Only a semi-quantitative prediction of the surface elasticity is obtained for [pluronic]≤1×10(-3) mM.


Asunto(s)
Litio/química , Polietilenglicoles/química , Poliestirenos/química , Glicoles de Propileno/química , Sales (Química)/química , Adsorción , Reología , Tensión Superficial
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