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1.
Appl Radiat Isot ; 200: 110963, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37549614

ABSTRACT

This work reports the influence of terbium trivalent ions on growing kinetics and the phase in hafnium oxide nanoparticles, as well as response to radiation in the range from 256 to 286. The nanoparticles were obtained by the hydrothermal route maintaining the temperature constant and varying the reaction time and the terbium concentration. The results show a gradual change in the phase with the concentration of terbium trivalent ions, going from the monoclinic phase, present at low concentrations, to the tetragonal phase, which appears from dopant concentrations greater than 5% at., increasing in amount with concentration of dopant. These phases appear as two perfectly defined morphologies. Furthermore, there is a significant change in radiative lifetimes when the tetragonal phase appears.

2.
Appl Radiat Isot ; 186: 110266, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35512416

ABSTRACT

The present work reports the study of the thermally coupled energy levels of the trivalent europium ion in the barium hafnate matrix, in the temperature range of 289.7-323.8 K, through the application of ultraviolet radiation. Barium hafnate doped with 1, 3, and 5 atomic % trivalent europium ion was synthesized by the hydrothermal route, using chlorides as precursor elements. X-ray diffraction analysis indicates that the material crystallized in the perovskite cubic phase of barium hafnate, according to diffraction card file number #24-0102. Using high-resolution transmission electron microscopy, it was observed that the obtained crystals have an average size of 10 nm. From the photoluminescent analysis at room temperature, it was found that the sample doped with 3.0% atomic of trivalent europium displayed with the highest luminescent emission, while the photoluminescent analysis as a function of temperature showed that the bands associated with the 5D0 → 7FJ (J = 1,2,3,4) transitions have a strong dependence on temperature in the physical range.

3.
Appl Radiat Isot ; 153: 108815, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31344649

ABSTRACT

In this paper, luminescent properties of Europium trivalent ion in the matrix with unbalanced charge of barium hafnate under UV radiation, with special emphasis on the 5D0 → 7F0 transition are reported. The synthesis was conducted by the hydrothermal route at 200 °C with a reaction time of 90 min using chlorides as raw materials. In order to determinate the luminescent quenching concentration, the samples were doped with different amounts of Europium trivalent ions being the sample doped with 1 and 3% at of Eu3+ which shows the highest luminescent emission. X-ray diffraction analysis showed that the material crystallize in the cubic perovskite structure with space group Pm-3m. The Energy Dispersive Spectroscopy (EDS) shows there are not elements other those that Ba, Hf, O and Eu in the synthesized material. Photoluminescent emission spectra show peaks of emission associated with the 5D0 → 7FJ (J = 0,1,2,3,4) transitions, characteristics of europium ion. The 5D0 → 7F0 transition centered at 580 nm showed an unusual great intensity when it was excited with the wavelength associated with the charge transfer band (272 nm). Finally the decay time was measured in the 5D0 → 7FJ (J = 0,1,2,3,4) transitions using the sample doped with Eu3+ (3% at).

4.
Rehabilitación (Madr., Ed. impr.) ; 48(3): 151-159, jul.-sept. 2014. tab
Article in Spanish | IBECS | ID: ibc-123990

ABSTRACT

Introducción: La evaluación funcional de mano con una pauta validada permite objetivar las intervenciones en rehabilitación, optimizando tratamientos en beneficio de niños y jóvenes con afecciones neuro-músculo-esqueléticas. Objetivo: Adaptar y validar la pauta Bilan 400 points de aplicación en adultos, en población de 7 a 17 años de edad en condición de discapacidad.Materiales y métodos: Se traduce la pauta Bilan 400 points del francés (original) al español y viceversa; la validez de apariencia se obtiene mediante concordancia entre 11 expertos en el tema. Se capacita a 25 terapeutas ocupacionales en el manejo de la pauta y se controla la variabilidad entre observadores. Se evalúan la consistencia interna y la validez de constructo con análisis de componentes principales con rotación varimax, en una muestra aleatoria de 153 niños y jóvenes que cumplían con los requisitos de inclusión. Resultados: Alta concordancia entre expertos (80 al 100%) para los ítems de la pauta. La consistencia interna varió entre 0,94 y 0,98 de α de Cronbach para las distintas dimensiones, en las manos derecha e izquierda. Se logra la identificación de 3 dimensiones; en la primera se ubican las subdimensiones de movilidad de dedos, pulgar, muñeca y antebrazo; en la segunda, las subdimensiones de prensión fina y gruesa y desplazamiento de objetos, y en la tercera, las subdimensiones de destrezas manipulativas de utensilios de alimentación, vestuario y herramientas escolares. Conclusión: La pauta Bilan 400 points modificada es válida y confiable como instrumento evaluativo de funcionalidad de la mano en población de 7 a 17 años, en condición de discapacidad neuro-músculo-esquelética (AU)


Introduction: Functional assessment of the hand with a validated scale can be used to evaluate rehabilitation interventions and optimize treatments that benefit children and youngsters with neuromusculoskeletal diseases. Objective: To adapt and validate the Bilan 400 points scale, used in adult patients, to a population aged 7 to 17 years old with some degree of disability. Materials and methods: The Bilan 400 points scale was translated from the original French to Spanish and vice-versa; face validity was obtained through consensus among 11 experts on the topic. Twenty-five occupational therapists were instructed in the management of the protocol and variability was controlled among the observers. Internal consistency was also evaluated. Construct validity was evaluated using main components analysis with varimax rotation in a random sample of 153 children and young people who met the inclusion criteria. Results: There was strong agreement among the experts (80% to 100%) on the items of the protocol. The internal consistency varied between a Cronbach’s of 0.94 and 0.98 for the different dimensions, for the right and left hands. Three dimensions were identified: the first consisted of the sub-dimensions of mobility of the fingers, thumb, wrist and forearm; the second consisted of the sub-dimensions of precision grip, power grip and displacement of objects; and the third was the sub-dimension of manipulative skills of food utensils, clothing and school items. Conclusion: The modified Bilan 400 points scale is a valid and reliable assessment tool that measures hand functionality in children and youngsters between 7 and 17 years of age with neuromusculoskeletal disability (AU)


Subject(s)
Humans , Musculoskeletal Diseases/rehabilitation , Disability Evaluation , Hand Injuries/rehabilitation , Hand/physiology , Musculoskeletal Diseases/physiopathology , Disabled Persons/classification , International Classification of Functioning, Disability and Health , Activities of Daily Living
5.
Appl Radiat Isot ; 92: 91-5, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25016246

ABSTRACT

In this work, the photoluminescent (PL), cathodoluminescent (CL) and thermoluminescent (TL) properties of hafnium oxide films doped with trivalent dysprosium ions are reported. The films were deposited on glass substrates at temperatures ranging from 300 to 600°C, using chlorides as precursor reagents. The surface morphology of films showed a veins shaped microstructure at low deposition temperatures, while at higher temperatures the formation of spherical particles was observed on the surface. X-ray diffraction showed the presence of HfO2 monoclinic phase in the films deposited at temperatures greater than 400°C. The PL and CL spectra of the doped films showed the highest emission band centered at 575nm corresponding to the transitions (4)F9/2→(6)H13/2, which is a characteristic transition of Dy(3+) ion. The greatest emission intensities were observed in samples doped with 1 atomic percent (at%) of DyCl3 in the precursor solution. Regarding the TL behavior, the glow curve of HfO2:Dy(+3) films exhibited spectrum with one broad band centered at about 150°C. The highest intensity TL response was observed on the films deposited at 500°C.

6.
Scand J Immunol ; 79(1): 1-11, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24117537

ABSTRACT

A reduced proliferation to T cell mitogens is observed in vitro in murine cells isolated during the acute phase of Toxoplasma gondii infection. Foxp3(+) regulatory T cells (Tregs) mediate this suppression, which is interleukin (IL)-2 dependent. In this work, we analysed the mechanism of this Treg-mediated suppression. We found that removal of antigen-presenting cells (APC) from spleen cells from infected mice did not modify suppression but further elimination of Tregs led to a restored proliferation, demonstrating that Tregs mediate suppression in the absence of APC. Production of IL-2 by T cells from infected animals was abolished but partially restored when Tregs were removed. However, IL-2 levels and T cell proliferation were restored when Tregs and T cells were separated by transwells, indicating that Tregs require close proximity with T cells to induce suppression. Tregs from infected mice were able to reduce proliferation of CTLL-2 cells in the classical IL-2 bioassay, strongly suggesting that Tregs compete with T cells for IL-2. We found that T cells from infected mice died after a few rounds of division in vitro, but addition of recombinant IL-2 or removal of Tregs abolished this effect. Our results showed that suppression of T cell proliferation during acute Toxoplasma gondii infection is the result of death of proliferating T cells by Treg-mediated IL-2 competition. Thus, immunosuppression is due to death of proliferating T cells as a consequence of low IL-2 availability.


Subject(s)
Cell Proliferation , Interleukin-2/immunology , T-Lymphocytes, Regulatory/immunology , T-Lymphocytes/immunology , Toxoplasmosis/immunology , Animals , Cell Survival/drug effects , Cell Survival/immunology , Female , Flow Cytometry , Fluorescent Antibody Technique , Forkhead Transcription Factors/genetics , Forkhead Transcription Factors/immunology , Forkhead Transcription Factors/metabolism , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Host-Parasite Interactions/immunology , Interleukin-2/metabolism , Interleukin-2/pharmacology , Mice , Mice, Inbred C57BL , Mice, Transgenic , Spleen/cytology , Spleen/immunology , Spleen/metabolism , T-Lymphocytes/metabolism , T-Lymphocytes, Regulatory/metabolism , Toxoplasma/immunology , Toxoplasma/physiology , Toxoplasmosis/metabolism , Toxoplasmosis/parasitology
7.
Work ; 41 Suppl 1: 2569-75, 2012.
Article in English | MEDLINE | ID: mdl-22317107

ABSTRACT

UNLABELLED: This study examines changes in body temperature generated in the wrist area through sensory thermography technique because of highly repetitive movements, proving with this technique that there is a decreased ability to perform muscular work, and thereby assess possible pathologies of Cumulative Trauma Disorders (CTDs). METHODS: Two healthy right-handed individuals, who performed repetitive work, emulating an operation of the textile industry for three days, generated DTA in the area of the wrist. The evaluation time was of 3 hours 30 minutes in a controlled temperature between 20 and 25°C, 20 minutes stabilization time at the beginning and end of the operation. RESULTS: The maximum temperatures reached were on the right wrist (RW) of 35. 078°C over a period of 1 hour 41 minutes 52 seconds; and on the left wrist (LR), 34.663°C over a period of 2 hours 42 minutes 51 seconds, detected discomfort in their right shoulder and wrist in the time range which identified the highest temperatures. It was shown that the data does not fit a normal distribution for RW and LW; the data fit the three- parameters Weibull distribution for WR and LW with a correlation coefficient between 0.93 to 0.99.


Subject(s)
Cumulative Trauma Disorders/physiopathology , Movement/physiology , Occupational Diseases/physiopathology , Skin Temperature , Thermography , Adult , Cumulative Trauma Disorders/complications , Humans , Male , Occupational Diseases/complications , Shoulder Pain/etiology , Shoulder Pain/physiopathology , Textiles , Wrist/physiology , Young Adult
8.
Alerg. inmunol. clin ; 27(3/4): 58-64, 2009. graf
Article in Spanish | LILACS | ID: lil-614165

ABSTRACT

La incorporación del concepto "Calidad de Vida" ha generado entre los médicos y el personal relacionado con la salud, un cambio de actitud en el cual el único objetivo es el beneficio del paciente. "La calidad de vida relacionada con la salud evalúa no sólo las alteraciones producias por la enfermedad, sino el modo en que el paciente las percibe y los efectos beneficioso o no del tratamiento. Objetivo: describir la frecuencia de las alteraciones de la calidad de vida en pacientes con rinitis.


The object to study was to evaluate quality of life in patients with rhinitis.


Subject(s)
Humans , Male , Female , Quality of Life , Surveys and Questionnaires/standards , Rhinitis , Rhinitis/therapy
9.
Cir. & cir ; 67(2): 59-65, mar.-abr. 1999. ilus, graf, tab
Article in Spanish | LILACS | ID: lil-254544

ABSTRACT

Estudio de investigación experimental, prospectivo y comparativo, con el objeto de evaluar los efectos de la aplicación exógena de colágena tipo I, Polivinilpirrolidona (PVP) y heparina, en túneles musculares fibrocolágenos, en la extremidad isquémica de la rata, para inducir neovascularización o angiogénesis. Se usó un modelo de isquemia en la extremidad posterior derecha de 40 ratas Wistar en dos tiempos. 1º Ligadura de la arteria iliaca común vía abdominal y colocación de una protesis de silasticpoliéster en el músculo gracilis para la generación de un túnel fibrocolágeno. 2º Ocho semanas después, exposición del paquete vascular femoral, ligadura de esta arteria, localización y extracción de la prótesis, perforación y lavado del túnel fibrocolágeno y aplicación de sustancias. En el grupo I se aplicó solución fisiológica, en el grupo II colágena tipo I con PVP, en el grupo III heparina sódica y grupo IV colágena tipo I con (PVP) y heparina sódica. Para la valoración se llevó a cabo angiografía de las extremidades tratadas, cuantificando el número de intersecciones en una superficie milimétrica de 50 x 50 mm. El mayor número de intersecciones se obtuvo en el grupo IV con una medida de 20.22 contra una media de 13.5 intersecciones en el grupo I (control con sol. fisiológica) = p de 0.14 mediante el análisis de varianza para comparar dos grupos (ANOVA). El estudio demuestra mayor angiogénesis en el músculo isquemico de la rata, si se aplica colágena tipo I con (PVP) y heparina


Subject(s)
Animals , Rats , Arterial Occlusive Diseases , Disease Models, Animal , Heparin/administration & dosage , Ischemia/chemically induced , Neovascularization, Pathologic/chemically induced , Povidone/administration & dosage
13.
Am J Trop Med Hyg ; 27(4): 747-50, 1978 Jul.
Article in English | MEDLINE | ID: mdl-567439

ABSTRACT

The effectiveness of five treatment regimens was compared to mice during acute and late infection with Toxoplasma gondii. Parasitic cure rates, as judged by failure of brain tissue from surviving mice to produce infection when inoculated into clean mice, were as follows: pyrimethamine + sulfamethoxypyridazine, 92%; clindamycin + sulfamethoxypyridazine, 75%; spiramycin + sulfamethoxypyridazine, 16.7%; trimethoprim + sulfamethoxypryridazine alone, 0%. Pyrimethamine + sulfamethoxypyridazine was the most effective combination against acute toxoplasmosis in mice.


Subject(s)
Toxoplasmosis, Animal/drug therapy , Acute Disease , Animals , Clindamycin/administration & dosage , Drug Therapy, Combination , Humans , Leucomycins/administration & dosage , Mice , Pyrimethamine/administration & dosage , Sulfamethoxazole/administration & dosage , Sulfamethoxypyridazine/administration & dosage , Trimethoprim/administration & dosage
14.
Infection ; 6(3): 144, 1978.
Article in English | MEDLINE | ID: mdl-680984

ABSTRACT

Duocoxin, nicrazine and amprol plus showed no therapeutic effect in 50 mice each of which was infected with 25,000 organisms of a virulent Toxoplasma strain.


Subject(s)
Amprolium/therapeutic use , Carbanilides/therapeutic use , Coccidiostats/therapeutic use , Nicarbazin/therapeutic use , Picolines/analogs & derivatives , Sulfanilamides/therapeutic use , Sulfaquinoxaline/therapeutic use , Toxoplasmosis, Animal/drug therapy , Animals , Drug Combinations , Drug Evaluation, Preclinical , Male , Mice
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