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1.
ACS Appl Mater Interfaces ; 15(26): 32024-32036, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37340706

RESUMO

We describe the proof of concept of a portable testing setup for the detection of triacetone triperoxide (TATP), a common component in improvised explosive devices. The system allows for field testing and generation of real-time results to test for TATP vapor traces in air by simply using circulation of the air samples through the sensing mechanism under the air conditioning system of an ordinary room. In this way, the controlled trapping of the analyte in the chemical sensor gives reliable results at extremely low concentrations of TATP in air under real-life conditions, suitable for daily use in luggage storage for airlines or a locker room for a major sporting event. The reported fluorescent methodology is very sensitive and selective, allowing for the trapping of triacetone triperoxide in the chemical sensor to give reliable results at very low concentrations in air under ambient conditions, by comparing the fluorescence of the material before and after exposition to TATP traces in air.

2.
Materials (Basel) ; 11(9)2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30235867

RESUMO

Molybdenum chalcogenides present interesting properties beyond their superconducting critical temperatures and upper critical magnetic fields, making them suitable for potential applications in tribology, batteries, catalysis, or thermopower. In this study, Mo15S19 nanoparticles with an average diameter of 10 nm were synthesized via the reaction of ammonium molybdate with hydrochloric acid and elemental sulfur as reducers at 245 °C. The oxidation to MoO3 in air was efficiently avoided by using linseed oil as a reaction medium and dispersant. Scanning electron microscopy (SEM) micrographs of the as-prepared samples revealed the presence of few-micron-size aggregates, while transmission electron microscopy (TEM) characterization evidenced that the samples were polynanocrystalline with a high degree of homogeneity in size (standard deviation of 2.7 nm). The absence of the first-order (00l) reflection in the X-ray diffraction pattern was also indicative of the absence of Mo3S4 stacking, suggesting that it was a non-layered material. A dispersion of the nanoparticles in linseed oil has been studied as a lubricant of steel⁻steel sliding contacts, showing the formation of a surface layer that reduces wear and mean friction coefficients with respect to the base oil.

3.
Rev. cuba. endocrinol ; 29(2): 1-16, mayo.-ago. 2018. ilus, tab
Artigo em Espanhol | CUMED | ID: cum-73078

RESUMO

Introducción: el carcinoma diferenciado del tiroides representa la neoplasia maligna más frecuente en Endocrinología. Su presentación clínica y su diagnóstico se han modificado gracias a la disponibilidad de herramientas diagnósticas, tales como, el ultrasonido tiroideo y la biopsia aspirativa con aguja fina. Objetivos: describir las características clínicas, ultrasonográficas y citohistológicas de los pacientes intervenidos quirúrgicamente por enfermedad tiroidea maligna, y evaluar en ellos la prevalencia de hipocalcemia crónica y el valor de la hormona estimulante del tiroides. Métodos: se realizó un estudio descriptivo retrospectivo, en el cual se revisaron los informes consecutivos de Anatomía Patológica de todos los pacientes intervenidos quirúrgicamente por enfermedad tiroidea nodular en el Hospital General Provincial Camilo Cienfuegos en el periodo comprendido de enero de 2012 a diciembre 2014. La muestra estuvo conformada por 118 historias clínicas de pacientes operados por enfermedad tiroidea nodular que reunieron los criterios siguientes: datos clínicos, resultados según los criterios de Bethesda de la punción aspirativa con aguja fina, del ultrasonido del tiroides y la biopsia. A estos pacientes se les citó para una evaluación clínica y se les determinó en ayunas, la hormona estimulante del tiroides y en 2 días diferentes, la calcemia. Los pacientes fueron clasificados en portadores de: enfermedad tiroidea maligna (n= 39) y enfermedad tiroidea benigna (n= 79). Resultados: clínicamente solo el 15,4 por ciento de los pacientes con enfermedad tiroidea maligna presentaron dolor o molestia espontánea y/o a la palpación de la glándula del tiroides. La enfermedad tiroidea maligna se diagnosticó en todas las categorías del citodiagnóstico: I: 1/1 (100 por ciento), II: 8/83 (9,6 pòr ciento), III: 4/6 (66,7 por ciento), IV: 2/2 (100 por ciento), V: 18/20 (90 por ciento), VI: 6/6 (100 por ciento). El carcinoma papilar representó la neoplasia más frecuentemente diagnosticada (37/39 pacientes), el 33,3 por ciento de estos enfermos mostraron cifras de hormona estimulante del tiroides por encima de 2,0 mU/L, y hubo un 46,15 por ciento de hipocalcemia crónica. Conclusiones: el carcinoma papilar fue la neoplasia más frecuentemente diagnosticada en los pacientes operados por enfermedad tiroidea maligna. La mayoría de estos pacientes tuvieron un comportamiento subclínico, un tercio de valores no óptimos de la hormona estimulante del tiroides y una prevalencia alta de hipocalcemia crónica(AU)


ntroduction: differentiated thyroid carcinoma represents the most frequent malignant neoplasia in Endocrinology. Its clinical presentation and diagnosis have been modified thanks to the availability of diagnostic tools, such as thyroid ultrasound and fine needle aspiration biopsy. Objectives: to describe the clinical, ultrasonographic and cytohistological characteristics of patients undergoing surgery for malignant thyroid disease, and to evaluate in them the prevalence of chronic hypocalcemia and the value of the thyroid´s stimulating hormone. Methods: a retrospective descriptive study was carried out, in which consecutive reports of Pathological Anatomy of all patients surgically treated for nodular thyroid disease at Camilo Cienfuegos Provincial General Hospital in the period from January 2012 to December 2014 were reviewed. The sample consisted of 118 medical records of patients operated on for nodular-thyroid disease that met the following criteria: clinical data, results according to the Bethesda criteria of fine needle aspiration, thyroid ultrasound and biopsy. These patients were called for a clinical evaluation and they were indicated to be fasting. The patients were classified into carriers of: ETM (n=. 39) and benign thyroid disease (n= 79). Results: in clinical terms, only 15.4 percent of the patients with malignant thyroid disease presented spontaneous pain or discomfort, and / or during palpation of the thyroid glands. Malignant thyroid disease was diagnosed in all categories of cytodiagnosis: I: 1/1 (100 percent), II: 8/83 (9.6 percent), III: 4/6 (66.7 percent), IV: 2/2 (100 percent), V: 18/20 (90 percent), VI: 6/6 (100 percent). Papillary carcinoma represented the most frequently diagnosed neoplasm (37/39 patients); 33.3 percent of these patients showed thyroid stimulating hormone levels above 2.0 mU / L, and there was 46.15 percent of chronic hypocalcemia. Conclusions: papillary carcinoma was the most frequently diagnosed neoplasm in patients operated of malignant thyroid disease. The majority of these patients had a subclinical behavior, a third of non-optimal values of the thyroid stimulating hormone and a high prevalence of chronic hypocalcemia(AU)


Assuntos
Humanos , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide , Biópsia por Agulha Fina/métodos , Carcinoma Papilar , Epidemiologia Descritiva , Estudos Retrospectivos
4.
Rev. cuba. endocrinol ; 29(2): 1-16, mayo.-ago. 2018. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-978381

RESUMO

Introducción: el carcinoma diferenciado del tiroides representa la neoplasia maligna más frecuente en Endocrinología. Su presentación clínica y su diagnóstico se han modificado gracias a la disponibilidad de herramientas diagnósticas, tales como, el ultrasonido tiroideo y la biopsia aspirativa con aguja fina. Objetivos: describir las características clínicas, ultrasonográficas y citohistológicas de los pacientes intervenidos quirúrgicamente por enfermedad tiroidea maligna, y evaluar en ellos la prevalencia de hipocalcemia crónica y el valor de la hormona estimulante del tiroides. Métodos: se realizó un estudio descriptivo retrospectivo, en el cual se revisaron los informes consecutivos de Anatomía Patológica de todos los pacientes intervenidos quirúrgicamente por enfermedad tiroidea nodular en el Hospital General Provincial Camilo Cienfuegos en el periodo comprendido de enero de 2012 a diciembre 2014. La muestra estuvo conformada por 118 historias clínicas de pacientes operados por enfermedad tiroidea nodular que reunieron los criterios siguientes: datos clínicos, resultados según los criterios de Bethesda de la punción aspirativa con aguja fina, del ultrasonido del tiroides y la biopsia. A estos pacientes se les citó para una evaluación clínica y se les determinó en ayunas, la hormona estimulante del tiroides y en 2 días diferentes, la calcemia. Los pacientes fueron clasificados en portadores de: enfermedad tiroidea maligna (n= 39) y enfermedad tiroidea benigna (n= 79). Resultados: clínicamente solo el 15,4 por ciento de los pacientes con enfermedad tiroidea maligna presentaron dolor o molestia espontánea y/o a la palpación de la glándula del tiroides. La enfermedad tiroidea maligna se diagnosticó en todas las categorías del citodiagnóstico: I: 1/1 (100 por ciento), II: 8/83 (9,6 pòr ciento), III: 4/6 (66,7 por ciento), IV: 2/2 (100 por ciento), V: 18/20 (90 por ciento), VI: 6/6 (100 por ciento). El carcinoma papilar representó la neoplasia más frecuentemente diagnosticada (37/39 pacientes), el 33,3 por ciento de estos enfermos mostraron cifras de hormona estimulante del tiroides por encima de 2,0 mU/L, y hubo un 46,15 por ciento de hipocalcemia crónica. Conclusiones: el carcinoma papilar fue la neoplasia más frecuentemente diagnosticada en los pacientes operados por enfermedad tiroidea maligna. La mayoría de estos pacientes tuvieron un comportamiento subclínico, un tercio de valores no óptimos de la hormona estimulante del tiroides y una prevalencia alta de hipocalcemia crónica(AU)


ntroduction: differentiated thyroid carcinoma represents the most frequent malignant neoplasia in Endocrinology. Its clinical presentation and diagnosis have been modified thanks to the availability of diagnostic tools, such as thyroid ultrasound and fine needle aspiration biopsy. Objectives: to describe the clinical, ultrasonographic and cytohistological characteristics of patients undergoing surgery for malignant thyroid disease, and to evaluate in them the prevalence of chronic hypocalcemia and the value of the thyroid´s stimulating hormone. Methods: a retrospective descriptive study was carried out, in which consecutive reports of Pathological Anatomy of all patients surgically treated for nodular thyroid disease at Camilo Cienfuegos Provincial General Hospital in the period from January 2012 to December 2014 were reviewed. The sample consisted of 118 medical records of patients operated on for nodular-thyroid disease that met the following criteria: clinical data, results according to the Bethesda criteria of fine needle aspiration, thyroid ultrasound and biopsy. These patients were called for a clinical evaluation and they were indicated to be fasting. The patients were classified into carriers of: ETM (n=. 39) and benign thyroid disease (n= 79). Results: in clinical terms, only 15.4 percent of the patients with malignant thyroid disease presented spontaneous pain or discomfort, and / or during palpation of the thyroid glands. Malignant thyroid disease was diagnosed in all categories of cytodiagnosis: I: 1/1 (100 percent), II: 8/83 (9.6 percent), III: 4/6 (66.7 percent), IV: 2/2 (100 percent), V: 18/20 (90 percent), VI: 6/6 (100 percent). Papillary carcinoma represented the most frequently diagnosed neoplasm (37/39 patients); 33.3 percent of these patients showed thyroid stimulating hormone levels above 2.0 mU / L, and there was 46.15 percent of chronic hypocalcemia. Conclusions: papillary carcinoma was the most frequently diagnosed neoplasm in patients operated of malignant thyroid disease. The majority of these patients had a subclinical behavior, a third of non-optimal values of the thyroid stimulating hormone and a high prevalence of chronic hypocalcemia(AU)


Assuntos
Humanos , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Biópsia por Agulha Fina/métodos , Carcinoma Papilar/diagnóstico por imagem , Epidemiologia Descritiva , Estudos Retrospectivos
5.
Nanomaterials (Basel) ; 8(7)2018 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-30037145

RESUMO

Transition metal oxides and chalcogenides have recently attracted great attention as the next generation of 2-D materials due to their unique electronic and optical properties. In this study, a new procedure for the obtaining of highly crystalline α-MoO3 is proposed as an alternative to vapor-phase synthesis. In this approach, a first reaction between molybdate, citrate and thiourea allowed to obtain MoS2, which-upon calcination at a temperature of 650 °C in the presence of g-C3N4-resulted in MoO3 with a definite plate-like shape. The colorless (or greenish) α-MoO3 nanoplates obtained with this procedure featured a multilayer stack structure, with a side-length of 1⁻2 µm and a thickness of several nanometers viewed along the [010] direction. The nucleation-growth of the crystal can be explained by a two-dimensional layer-by-layer mechanism favored by g-C3N4 lamellar template.

6.
ACS Appl Mater Interfaces ; 8(38): 24999-5004, 2016 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-27617785

RESUMO

We have developed new functionalized polymers capable of being easily coated by gold nanoparticles, uniformly distributed on the surface of the polymers, by simply adding a gold(III) solution in water to the polymers. The polymer-supported gold nanoparticle material was used as an efficient portable and reusable catalyst for Suzuki reactions in mixed organic-aqueous solvents.

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