Low-Temperature Synthesis of Bi2S3 Hierarchical Microstructures via Co-Precipitation and Digestive Process in Aqueous Medium.

Bismuth sulfide (Bi2S3) nanostructures have gained significant attention in the fields of catalysis, optoelectronics, and biomedicine due to their unique physicochemical properties. This paper introduces a simple and cost-effective method for producing Bi2S3 microstructures at low temperatures (25 and 70 °C). These microstructures are formed by the hierarchical self-assembly of Bi2S3 nanoparticles, which are typically 15-40 nm in size. The nanoparticles are synthesized by the co-precipitation of thioglycolic acid, thioacetamide, and bismuth nitrate in water. The study delves into the phase composition and morphological evolution of the microstructures, concerning the chemical composition of the solution and the synthesis temperature. X-ray analysis has confirmed the formation of single-phase bismuthinite Bi2S3. The synthesis process generates primary building blocks in the form of 15-40 nm Bi2S3 nanocrystals, which then go through a hierarchical self-assembly process to produce a range of micrometer-sized structures. A scanning electron microscopy examination revealed that the primary nanoparticles self-assemble into quasi-1D worm-like nanostructures, which then self-assemble to create sponge-shaped microstructures. These structures subsequently self-organize and refine into either flower- or dandelion-like microstructures, mostly depending on the synthesis temperature and the chemistry of the digestion medium.

Estrategia pedagógica para la preparación del profesor de Educación Física como mediador de conflictos

El logro de una educación accesible y de calidad para todos los ciudadanos es, en la actualidad, una de las prioridades para la formación de profesionales, puesto que estos contribuyen al desarrollo de un sistema de educación reconocido, tanto a nivel nacional como internacional. De esta manera, el estudio realizado se propuso como objetico diseñar una estrategia pedagógica para la preparación al profesor como mediador de conflictos en la clase de Educación Física, de las escuelas secundarias básicas del municipio La Habana del Este. Para ello, se utilizó un enfoque mixto, con el fin de agrupar los análisis de documentos y las descripciones cualitativas junto a tablas y figuras para complementar y enriquecer el estudio cualitativa y cuantitativamente. Como principal resultado, se evidenciaron los principios, premisas y el procedimiento metodológico para la integración de influencias educativas. En sentido general, la preparación del profesor como mediador de conflictos da respuesta a los programas priorizados del Ministerio de Educación en su agenda de perfeccionamiento hacia el 2030 y del Instituto Nacional de Deporte, Educación Física y Recreación.

A concretização de um ensino acessível e de qualidade para todos os cidadãos é atualmente uma das prioridades para a formação dos profissionais, uma vez que contribuem para o desenvolvimento de um sistema educativo reconhecido, tanto a nível nacional como internacional. Desta forma, o estudo propôs desenhar uma estratégia pedagógica para preparar o professor como mediador de conflitos nas aulas das escolas secundárias básicas do município de La Habana del Este. Para isso, foi utilizada uma abordagem mista, de modo a agrupar a análise de documentos e descrições qualitativas com tabelas e figuras para complementar e enriquecer o estudo, tanto qualitativo como quantitativo. O principal resultado é a integração das influências educacionais, os fundamentos, princípios, premissas e procedimento metodológico. De um modo geral, é evidente a preparação do professor como mediador de conflitos, respondendo aos programas prioritários do Ministério da Educação em aperfeiçoamento para 2030 e do Instituto Nacional de Esportes, Educação Física e Recreação.

The achievement of accessible and quality education for all citizens is, currently, one of the priorities for the training of professionals, since they contribute to the development of a recognized education system, both nationally and internationally. In this way, the objective of the study carried out was to design a pedagogical strategy to prepare the teacher as a conflict mediator in the Physical Education class, in the basic secondary schools of the municipality of La Habana del Este. For this purpose, a mixed approach was used, in order to group document analyzes and qualitative descriptions together with tables and figures to complement and enrich the study qualitatively and quantitatively. As the main result, the principles, premises and methodological procedure for the integration of educational influences were evident. In a general sense, the preparation of the teacher as a conflict mediator responds to the prioritized programs of the Ministry of Education in its improvement agenda towards 2030 and of the National Institute of Sports, Physical Education and Recreation.

Nanostructured PbSe Films Deposited by Spray Pyrolysis Using PbSe Colloidal Solutions.

This work describes the spray pyrolysis deposition of PbSe films, using as-prepared PbSe colloids as the starting solution. The PbSe colloids were prepared by using the alkahest approach, where Pb and Se precursors were made to react with the following green polyols: glycerin, ethylene glycol, and propylene glycol, to subsequently spray them onto glass substrates. The results of the characterization indicated that amine or thiol groups-free and single-phase rock-salt cubic PbSe powder was obtained, producing nanocrystals 16-30 nm in size. X-ray diffraction also showed that the PbSe films containing PbSeO3 and PbO·xH2O as impurity phases were produced during the deposition. The morphology of the powders and films was developed by a self-assembly process, in which the primary PbSe nanoparticles self-assemble to produce peanut-like microstructures. Additionally, a non-continuous and porous feature was formed in the thick films. Certain films revealed optical structures characterized by broad- and low-intensity bands resembling an exciton-like behavior. This could be attributed to the presence of nanocrystals with a size less than the Bohr radius, indicating reminiscent quantum effects. The results suggest that the usage of colloidal dispersions as spray solutions represents an effective approach to forming PbSe films, as well as that the synthesis method allows for the elimination of thiol and amine groups before deposition, significantly simplifying the process.

Perfil demográfico del cáncer de ovario en la Unidad de Tomografía por Emisión de Positrones Ciclotrón Hospital Carlos Andrade Marín / Demographic profile of ovarian cancer in the Positron Emission Tomography and Cyclotron Unit Carlos Andrade Marin Hospital

INTRODUCCIÓN. El cáncer de ovario es uno de los principales diagnósticos de malignidad en mujeres en nuestro país. La Tomografía por Emisión de Positrones -Tomografía Computarizada es importante porque puede establecer de manera correcta el estadio de la enfermedad así como puede determinar la recurrencia, incluso mejor que métodos diagnósticos como la Tomografía Simple o la Resonancia Magnética. OBJETIVO. Establecer los principales aspectos demográficos de los pacientes diagnosticados con cáncer de ovario que fueron evaluados en la Unidad Tomografía por Emisión de Positrones Ciclotrón del Hospital de Especialidades Carlos Andrade Marín de Quito-Ecuador. MATERIALES Y MÉTODOS. Estudio descriptivo retrospectivo. El número total de la población fue de 166 pacientes, y una muestra de 103 pacientes con criterios de inclusión y exclusión en la Unidad PET Ciclotrón del Hospital de Especialidades Carlos Andrade Marín de la ciudad de Quito, desde 2013 al 2018, obtenidas de bases estadísticas de la Unidad PET Ciclotrón y en la base de datos del sistema AS400 del Hospital. RESULTADOS. La mediana de edad de las pacientes con cáncer de ovario fue de 56 años (IQR 48 ­ 64; mínima: 13 y máxima 85). Al momento del estudio estuvieron casadas el 58,3% (60;103). El 43,7% (45;103) tuvieron un hijo. El 47,6% (49;103) tuvieron estudios de tercer nivel. El 64,0% (66;103) residieron en Quito. CONCLUSIÓN. Este perfil demográfico resaltó el poco acceso de este tipo de tecnología diagnóstica en pacientes con bajo nivel educativo y en lugares geográficamente alejados de Quito.

INTRODUCTION. Ovarian cancer is one of the main diagnoses of malignancy in women in our country. Positron Emission Tomography - Computed Tomography is important because it can correctly establish the stage of the disease as well as determine recurrence, even better than diagnostic methods such as Simple Tomography or Magnetic Resonance. OBJECTIVE. To establish the main demographic aspects of the patients diagnosed with ovarian cancer that were evaluated in the Cyclotron Positron Emission Tomography Unit of the Carlos Andrade Marín Specialty Hospital of Quito-Ecuador. MATERIALS AND METHODS. Retrospective descriptive study. The total number of the population was 166 patients, and a sample of 103 patients with inclusion and exclusion criteria in the PET Cyclotron Unit of the Carlos Andrade Marín Specialty Hospital of the city of Quito, from 2013 to 2018, obtained from statistical bases PET Cyclotron Unit and in the database of the AS400 system of the Hospital. RESULTS Hospital. The median age of ovarian cancer patients was 56 years (IQR 48-64; minimum: 13 and maximum 85). At the time of the study, 58,3% were married (60; 103). 43,7% (45; 103) had a child. 47,6% (49; 103) had third level studies. 64,0% (66; 103) resided in Quito. CONCLUSION. This demographic profile highlighted the little access of this type of diagnostic technology in patients with low educational level and in geographically remote places of Quito.

Hallazgos por imagen en pacientes con atresia de vías biliares en el Hospital de Especialidades Carlos Andrade Marín en el período de enero 2016 - marzo 2017 / Imaging findings in patients with biliary atresia in Carlos Andrade Marín Specialties Hospital, in the period between Jan 2016-Mar 2017

Introducción. Revisión de los hallazgos clínicos y radiológicos de la atresia de la vía biliar, una anomalía del desarrollo biliar que tiene un riesgo alto de mortalidad por las complicaciones asociadas si no se la corrige oportunamente. Material y métodos. Serie de siete casos reportados en el Hospital de Especialidades Carlos Andrade Marín en el periodo enero 2016 a marzo 2017, seis mujeres y un varón, todos con cuadro clínico de ictericia prolongada, acolia, patrón de colestasis, hallazgos por imagen y biopsias sugestivas de atresia de vías biliares. Resultados. Todos los pacientes presentaron ictericia y coluria, en exámenes de laboratorio patrón colestásico en todos los pacientes, en los estudios de imagen el hallazgo predominante en sospecha de atresia de vías biliares fue la ausencia de la vesícula biliar y el signo del cordón triangular solamente en tres pacientes, en la biopsia hepática todos mostraron algún grado de fibrosis hepática. Discusión. La atresia de la vía biliar es una enfermedad compleja y grave, en nuestra serie de casos se confirma la utilidad del ultrasonido como método de diagnóstico de atresia de vías biliares ya que es un método mucho más accesible que la resonancia magnética que generalmente tiene menor disponibilidad y mayor costo. Conclusión. El ultrasonido abdominal es una herramienta extremadamente valiosa en sospecha clínica de atresia de vías biliares, debe realizarse un diagnóstico oportuno para mejorar el pronóstico de los pacientes.

Introduction. This is a review of clinical and radiological findings of biliary atresia, an anomaly of biliary tree development that carries a high risk of mortality due to complications unless they are corrected in a short time. Materials and methods. We reviewed a series of seven cases reported at Carlos Andrade Marín Specialties Hospital, from January 2016 to March 2017. Six women and one male were followed. All of them showed clinical signs such as long term jaundice, cholestasis, as well as, imaging findings and liver biopsies, suggesting biliary tract atresia. Results. All patients presented jaundice and choluria, in laboratory tests a cholestasic pattern in all of them, in the imaging studies the predominant finding in suspicion of biliary atresia was the absence of gallbladder and the triangular cord sign in only three patients, in the liver biopsy all of them showed some degree of liver fibrosis. Discussion. Bile duct atresia is a complex and serious disease. In our case serie we confirmed the utility of ultrasound as diagnosis method in biliary duct atresia, is more available than magnetic resonance which is more expensive and less available in different centers. Conclusion. Abdominal ultrasound is an extremely valuable tool in clinical suspicion of biliary atresia, a timely diagnosis must be made to improve patient´s prognosis.

Osteoporosis, hallazgos en radiología convencional. Reporte de un caso / Osteoporosis, findings in conventional radiology. Report of a case

Introducción El presente artículo hace una revisión sobre los hallazgos radiológicos mediante radiografía simple, así como también los hallazgos clínicos en el diagnóstico de la osteopetrosis una enfermedad poco común que afecta el desarrollo normal óseo, se trata de un caso clínico reportado en el Hospital Pediátrico Baca Ortiz de la Ciudad de Quito. Reporte de Caso: Nos apoyamos en la presentación de un caso clínico de una paciente que acude por consulta externa con cuadro de fatiga y decaimiento de 2 años de evolución, se realizan exámenes complementarios demostrando presencia de anemia así como los hallazgos característicos de osteopetrosis por imagen posteriormente detallados. Conclusiones: La osteopetrosis es una enfermedad poco común, compleja y por lo menos con cuatro subtipos que difieren en la forma de herencia o de las manifestaciones adicionales asociadas, sin embargo todas se caracterizan por presentarse clínicamente con fatiga debido a anemia crónica, puede presentar o no hepatoesplenomegalia, conjuntamente asociadas siempre a osteoesclerosis difusa con ensanchamiento óseo, fracturas patológicas.

Introduction This article reviews the radiological findings by simple radiography as well as the clinical findings in the diagnosis of osteopetrosis, a rare disease that affects normal bone development. This is a case report reported in the Hospital Pediátrico Baca Ortiz at Quito City. Case Report: We rely on the presentation of a clinical case of a patient who goes by external consultation with fatigue and decay of 2 years of evolution, complementary tests are performed demonstrating the presence of anemia as well as the characteristic findings of osteopetrosis by image later detailed. Conclusions: Osteopetrosis is an uncommon, complex disease and with at least four subtypes that differ in the form of inheritance or associated additional manifestations, however all are characterized by presenting clinically with fatigue due to chronic anemia, may present or not hepatosplenomegaly, Always associated with diffuse osteosclerosis with bone spreading, pathological fractures.

Apoyo de los métodos de imagen para el Diagnóstico de Áscaris complicado en la vía biliar. Reporte de un caso / Advocacy for imaging methods for the diagnosis of complex Ascaris in the billiary tract: case report

Introducción: El presente caso nos permite revisar la utilidad de los diferentes métodos de imagen en la ascaridiasis en vía biliar a través del ultrasonido abdominal (US), la colangioresonancia (MRCP), la colangiopancreatografía retrógrada endoscópica (CPRE/ERCP) para el diagnóstico y/o tratamiento, para conocer el escenario de esta patología y definir los protocolos de diagnóstico por imagen y abordaje de la misma. La sensibilidad y especificidad de cada uno de los mismos en las diferentes series mundiales. Reporte de Caso: Nos apoyamos en la presentación de un caso clínico de una paciente proveniente del Oriente, que acude con cuadro de dolor abdominal tipo cólico en hipocondrio derecho, ictericia de 15 días de evolución, es transferida al Hospital Carlos Andrade Marín donde se realizaron estudios complementarios dentro de los cuales varios métodos de imagen, se describen los hallazgos en esta patología, así como protocolizar los métodos de imagen. Discusión: El ultrasonido es un método eficaz, accesible, no costoso, en manos expertas tiene elevada sensibilidad, al encontrar hallazgos concluyentes no se requiere el apoyo de otros métodos de imagen adicionales y en caso de ascaridiasis complicada como en nuestra paciente se debe proceder directamente a CPRE con extracción del parásito, en caso de no tener hallazgos concluyentes nos podemos apoyar de métodos como una colangioresonancia.

Introduction: This report let us review the usefulness of different imaging methods in common bile duct ascariasis like abdominal ultrasound, magnetic resonance cholangiopancreatography, endoscopic retrograde cholangiopancreatography (ERCP) for the diagnosis and / or treatment, to know the stage of this disease and to define the imaging protocols and addressing it. The sensitivity and specificity of each of them in different world series. Case Report: This is a clinical case of a patient from the Eastern región of Ecuador who was admitted to our hospital with a crampy abdominal pain focused in the right upper quadrant and jaundice that started 15 days before he was transferred to us. Imaging tests performed helped us to find out the problem and prescribe a propper treatment. Discusion: Ultrasound is an effective, accesible and inexpensive tool in expert hands. When the initial findings are not conclusive, other imaging methods can be applied, like Nuclear Magnetic Resonance cholangiopancreatography. Endoscopic retrograde cholangiopancreatography (ERCP) can be used in case of complicated ascariasis, as in our patient, to remove the parasite.

Distribution of Ophioglossum reticulatum L. in South America. A case of long-distance jump dispersal?

The objective of this exploratory work is to test the hypothesis that South American populations of Ophioglossum reticulatum L. derive from Africa. Spores cross the Atlantic transported by wind and arrive in South America in recurrent migration. Three-dimensional (backward and forward) trajectories of spores between Africa and South America were calculated using the Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT4). The model showed possible backward trajectories in the low troposphere arriving in South America with probable origin in Northwestern Africa. The results support the hypothesis of long-distance dispersal of the studied species. Including vertical motion in the model runs allowed obtaining valuable and novel information about the migration routes. The trade winds combined with the South American monsoon could be a dispersal vehicle for the disseminules from Northwestern Africa to the eastern slopes of the Andes. As the monsoon is a periodic regional atmospheric circulation pattern, transcontinental migration can be assumed to be a recurring phenomenon that provides genetic exchange and prevents speciation by reproductive isolation. Modelled forward trajectories connect the neotropics with Africa-Madagascar, but they seem to be less effective due to their travelling altitudes. This hypothesis might explain the absence of infraspecific taxa restricted to different geographic locations.

Isoetes pedersenii, a new species from Southern South America.

The name Isoetes pedersenii H.P. Fuchs (Lycophyta), a species known only from the Mburucuyá National Park, Corrientes, Argentina, is validated. Observations were carried out on herbarium material with stereoscopic, light and scanning electron microscopes. The species is described and typified. A diagnosis and discussion about its distribution and its relationship with the morphology of other species of Isoetes are provided.

Isoetes pedersenii, a new species from Southern South America

The name Isoetes pedersenii H.P. Fuchs (Lycophyta), a species known only from the Mburucuyá National Park, Corrientes, Argentina, is validated. Observations were carried out on herbarium material with stereoscopic, light and scanning electron microscopes. The species is described and typified. A diagnosis and discussion about its distribution and its relationship with the morphology of other species of Isoetes are provided.

O nome Isoetes pedersenii H.P. Fuchs (Lycophyta) foi validado para a espécie identificada apenas no Parque Nacional de Mburucuyá, em Corrientes na Argentina. Material preservado em herbário foi avaliado com microscópios estereoscó pico, de luz branca e eletrônico de varredura. A espécie foi descrita e tipificada. Um diagnóstico e uma discussão sobre a distribuição e relação com a morfologia de outras espécies de Isoetes são relatados.

Granuloma eosinófilo multifocal / Multifocal eosinophilic granuloma

Se presenta un caso con síntomas de poliuria, polidipsia y lesiones reticulonodulares diseminadas por ambos campos pulmonares, diagnosticado en su primer ingreso como granuloma eosinófilo pulmonar y diabetes insípida por biopsia pulmonar y examen óseo negativo. A los 3 años se ingresa por lesiones osteolíticas en el cráneo, la mandíbula y la séptima costilla derecha. Se revisa la literatura médica