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1.
Membranes (Basel) ; 13(6)2023 Jun 18.
Article in English | MEDLINE | ID: mdl-37367812

ABSTRACT

Impedance spectroscopy has been widely used for the study of the electrical properties of membranes for their characterization. The most common use of this technique is the measure of the conductivity of different electrolyte solutions to study the behavior and movement of electrically charged particles inside the pores of membranes. The objective of this investigation was to observe if there is a relation present between the retention that a nanofiltration membrane possesses to certain electrolytic solutions (NaCl, KCl, MgCl2, CaCl2, and Na2SO4) and the parameters that are obtained through IS measurements of the active layer of the membrane. To achieve our objective, different characterization techniques were performed to obtain the permeability, retention, and zeta potential values of a Desal-HL nanofiltration membrane. Impedance spectroscopy measurements were performed when a gradient concentration was present between both sides of the membrane to study the variation that the electrical parameters had with the time evolution.

2.
Acta Orthop Belg ; 87(3): 393-399, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34808711

ABSTRACT

This study investigates the clinical and radiological results of a tapered femoral stem (Corail®) and uncemented threaded acetabular cups (Tropic®) and in addition an analysis of the complications and retrieved implants was conducted. Between January 1990 and September 1998, 301 total hips arthroplasties in 268 patients were implanted. 78 patients (87 hips) had died and 9 patients (12 hips) had been lost to follow-up, leaving at the time of the latest follow-up 180 patients (202 hips). The mean age at surgery was 56,1 (27-75) years. Of the 154 unrevised hips, the median Harris and Merle d'Aubigne and Postel hip scores were 83,3 points and 15,3 points respectively at the latest follow-up. The median follow-up time was 16.9 years (10,4-25). No femoral component was revised for aseptic loosening ; osteolysis was observed in the 9,5% of the implants (13 stems). 48 hips (23%) were revised and 27 cups (56,2%) needed revision surgery because of massive polyethylene wear. Pelvic osteolysis was found out in 80 cups (58,8%). 87 hips (63,9%) showed signs of a progressive wear of the liner, more than 2mm in 48 hips. Kaplan-Meier survivorship analysis at 15 years follow-up was 81.2% with revision for any reason (85.8% for mechanical or radiographic loosening). High rates of polyethylene wear and the high prevalence of pelvic osteolysis are serious matters in these types of implants with high rates of revision at 15 years follow-up so we decided to abandon the concept of a threaded cup design in favor of a press-fit acetabular cup.


Subject(s)
Arthroplasty, Replacement, Hip , Hip Prosthesis , Acetabulum/diagnostic imaging , Acetabulum/surgery , Arthroplasty, Replacement, Hip/adverse effects , Follow-Up Studies , Humans , Prosthesis Design , Prosthesis Failure , Reoperation , Treatment Outcome
3.
Front Psychol ; 11: 2163, 2020.
Article in English | MEDLINE | ID: mdl-33013554

ABSTRACT

The garden is a major educational resource that can be used for all areas of knowledge from an interdisciplinary perspective as it reflects the complexity and interactions of the natural environment. This research was carried out in the academic years 2017-2018 and 2018-2019 with 418 participants of from the second, third, and fourth year of the Degree in Primary Education at the University of Valencia. The use of the garden and the landscape is analyzed as a non-formal context for training primary school teachers through sensory experiences that contribute to the development of scientific and artistic competencies. The study focused on the relationship between natural sounds and emotions to promote the environmental awareness and active listening that are necessary to improve auditory perception and reflect on health problems caused by noise pollution. During the project, we discovered the synergies between experimental sciences and artistic-musical expression and their importance for developing university students' competencies in the professional, personal, and collective spheres. The activities consisted of (1) a walking tour from the Faculty of Education to the garden at 1 km from the center, to reflect on the origin and characteristics of sound, emotions and their relationship with music; (2) sensory experiences in the garden through visual and auditory interaction with the landscape; and (3) an immersion in quasi-real scenarios created by virtual reality. The analysis was carried out by means of an ad hoc questionnaire with Likert-type items focused on aspects of the usefulness of gardens and the activities involved in the general and specific skills of the degree and open questions for reflections on emotional health, environmental sustainability, and artistic-musical creation as a representation of the environment. The results show the importance of the garden as a resource for training of primary teachers in a holistic and global approach that contributes to the development of teaching skills and the acquisition of knowledge based on sensory experiences with the landscape.

4.
Article in English | MEDLINE | ID: mdl-31892202

ABSTRACT

Parenting styles have been used to explain the effects of family socialization on children's learning skills. In this research, we have considered build an instrument for evaluating academic goals in the primary school stage, that allows us determine the relationships between the different types of goals and the different ways of establishing and policing the rules that the participants perceive from their parents. Those participating in this research were 550 pupils from of primary education. The Questionnaire on Academic Goals (QAG) has highly acceptable psychometric characteriztics. The analysis has shown the existence of four solid, well-defined factors. The relationships between the different types of goals and the different ways of establishing and policing the rules are verified. The pupils classified in the groups concerning the goals of social evaluation and reward were characterized by a more indulgent parenting style, determined by an absence of rules and limits for their children's behavior. On the other hand, those pupils classified in the groups concerning the goals of learning and achievement were characterized by parents with an inductive style, determined by the use of reasoning and explanations towards their children in so far as the consequences of breaking the rules.


Subject(s)
Academic Success , Child Behavior/psychology , Goals , Parenting/psychology , Schools , Students/psychology , Child , Cluster Analysis , Female , Humans , Male , Socialization
5.
Dermatol. argent ; 17(1): 32-39, ene.-feb. 2011. ilus, tab
Article in Spanish | LILACS | ID: lil-724133

ABSTRACT

Introducción. La mastocitosis representa un espectro de trastornos clínicos con un fenotipo común correspondiente a una hiperplasia de los mastocitos tisulares. Objetivo. Presentar la experiencia del Servicio de Dermatología del Hospital General de Niños Pedro de Elizalde en mastocitosis cutánea en los últimos 10 años. Diseño. Estudio retrospectivo y descriptivo, de corte transversal. Material y método. Se revisaron los archivos histológicos correspondientes al período que va de marzo de 1999 a marzo de 2099 del Servicio de Dermatología del Hospital General de Niños Pedro de Elizalde. Se consideraron como variables de estudio la edad al momento de la consulta, sexo, presencia de antecedentes personales y familiares, tipo clínico, localización, presencia de síntomas al examen físico, así como hallazos patológicos en los estudios complementarios. Los resultados se expresaron en promedios y porcentajes. Resultados. Presentamos 49 casos con diagnóstico clínico e histológico de mastocitosis cutánea; 33 pacientes (67,3%) de sexo masculino y 16 (32,7%) de sexo femenino. En cuanto al tipo clínico de mastocitosis, se encontraron 36 casos de urticaria pigmentosa (73,4%), 6 casos de mastocitoma solitario (12,2%), 5 casos de telangiectasia macularis eruptiva perstans (10,2%) y 2 casos donde coexistía mastocitoma solitario y urticaria pigmentosa (4%). No se encontraron casos de mastocitosis cutánea difusa. Las lesiones se distribuyen en tronco 25 casos (51%), en tronco y miembros 17 casos (34,6%), en cabeza, tronco y miembros 3 casos (6,1%), en miembros 3 casos (6,1%), en cabeza y tronco un caso (2,04%). Conclusión. En nuestra casuística, la manifestación clínica más frecuente fue la urticaria pigmentosa, similar a lo señalado en la bibliografía. Encontramos, a diferencia de lo publicado en la literatura, un predominio de sexo masculino y un alto porcentaje (10,2%) de pacientes pediátricos con la forma de telangiectasia macularis eruptiva perstans.


IntroductionMastocytosis represents a spectrum of clinical disorders with a common phenotype correspondingto hyperplasia of mast cells on tissues.ObjectiveTo present the experience of the Department of Dermatology, Hospital General de Niños Pedro deElizalde in cutaneous mastocytosis during the past 10 years.DesignRetrospective and descriptive, cross sectional study.Material and methodsHistological records were reviewed for the period March 1999-March 2009 at the Department ofDermatology, Hospital General de Niños Pedro de Elizalde.The variables considered were: age at time of consultation, gender, presence of personal andfamily history, clinical type, location, presence of symptoms by physical examination andabnormal findings on complementary studies.The results were expressed as averages and percentages.ResultsForty nine patients with clinical and histological diagnosis of cutaneous mastocytosis arepresented, 33 of them were male (67.3%) and 16 were female (32.7%).As regards to the clinical type of mastocytosis, 36 patients presented urticaria pigmentosa(73.4%), 6 had solitary mastocytoma (12.2%), 5 presented telagiectasia macularis eruptivaperstans (10.2%) and 2 patients presented solitary mastocytoma combined with urticariapigmentosa (4%). Diffuse cutaneous mastocytosis was not found.Twenty five patients had lesions distributed on the trunk (51%), trunk and limbs on 17 (34.6%),head, trunk and limbs 3 patients (6.1%), on limbs only 3 patients (6.1%), while head and trunktogether were affected on 1 patient (2.04%).ConclusionIn our caseload, the most frequent clinical manifestation was urticaria pigmentosa, similar tofindings in the literature.As opposed to published data we found predominance in males, and a high incidence (10.2%)of pediatric patients with telangiectasia macularis eruptiva perstans.


Subject(s)
Humans , Adolescent , Child , Mastocytosis, Cutaneous/classification , Mastocytosis, Cutaneous/diagnosis , Mastocytosis, Cutaneous/pathology , Mastocytosis, Cutaneous/drug therapy , Skin/pathology , Mastocytoma, Skin/diagnosis , Mast Cells/pathology , Retrospective Studies , Urticaria Pigmentosa/diagnosis
6.
Water Sci Technol ; 57(11): 1777-84, 2008.
Article in English | MEDLINE | ID: mdl-18547930

ABSTRACT

This paper presents the results of the long-term operation and monitoring of membrane fouling at several full-scale MF/RO water recycling facilities operated by Agbar in Spain. It was demonstrated that membranes give very reliable treatment enabling the production of high-grade recycled water, well disinfected and with the removal of all priority substances. The high organic and salt concentrations of raw wastewater combined to extremely high variations justified the implementation of sand filtration to protect MF/RO membranes. Membrane autopsy was used to better understand the predominant fouling mechanisms and optimise down-stream operation and membrane cleaning strategy. The main membrane pathologies are described with recommendation of an adequate cleaning strategy.


Subject(s)
Filtration/instrumentation , Water Purification/methods , Bioreactors , Filtration/methods , Membranes, Artificial , Osmosis , Sewage , Task Performance and Analysis , Waste Disposal, Fluid/methods
7.
Phys Rev Lett ; 96(14): 147202, 2006 Apr 14.
Article in English | MEDLINE | ID: mdl-16712115

ABSTRACT

By means of spin-polarized low-energy electron microscopy, we show that the magnetic easy axis of one to three atomic-layer thick cobalt films on Ru(0001) changes its orientation twice during deposition: One-monolayer and three-monolayer thick films are magnetized in plane, while two-monolayer films are magnetized out of plane. The Curie temperatures of films thicker than one monolayer are well above room temperature. Fully relativistic calculations based on the screened Korringa-Kohn-Rostoker method demonstrate that only for two-monolayer cobalt films does the interplay between strain, surface, and interface effects lead to perpendicular magnetization.

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