Feather iridescence of Coeligena hummingbird species varies due to differently organized barbs and barbules

Hummingbirds are perhaps the most exquisite bird species because of their prominent iridescence, created by stacks of melanosomes in the feather barbules. The feather colours crucially depend on the nanoscopic dimensions of the melanosome, and the displayed iridescence can distinctly vary, dependent on the spatial organization of the barbs and barbules. We have taken the genus Coeligena as a model group, with species having feathers that strongly vary in their spatial reflection properties. We studied the feather morphology and the optical characteristics. We found that the coloration of Coeligena hummingbirds depends on both the Venetian-blind-like arrangement of the barbules and the V-shaped, angular arrangement of the barbules at opposite sides of the barbs. Both the nanoscopic and microscopic organization of the hummingbird feather components determine the bird's macroscopic appearance. </p

Programa “Leo y comprendo” las capacidades de comprensión de texto en estudiantes de quinto de primaria de Lima Sur,2022

El presente trabajo tuvo como objetivo determinar que efecto produce el programa “Leo y comprendo” las capacidades de comprensión de texto en estudiantes de quinto de primaria de Lima Sur el que fue desarrollado mediante un enfoque cuantitativo, de tipo aplicada bajo un diseño preexperimental con un grupo experimental conformado por 31 estudiantes de quinto de primaria a quienes se les aplicó como instrumento una prueba de conocimientos de pre test y post test basada en la Evaluación Censal de Estudiantes 2016 elaborado por Equipo de la Oficina de Medición de Calidad del MINEDU. Se realizó un análisis estadístico y como la distribución de los datos no siguen la distribución normal se utilizó la prueba no paramétrica de Wilcoxon para determinar el impacto de la implementación del programa. Se concluye que el programa “Leo y comprendo” influyó de manera significativa en el desarrollo de las capacidades de comprensión de texto en los estudiantes que conformaron la muestra de esta investigación ya que se obtuvo un con un p-valor menor a 0.05

Sexual dichromatism of the Blue-throated Starfrontlet, <i>Coeligena helianthea</i>, hummingbird plumage

Among the many richly coloured birds, hummingbirds with their brilliant colouration are outstanding. We studied the plumage of male and female Blue-throated Starfrontlet, Coeligena helianthea, which exhibits a marked sexual dichromatism. The wide diversity of coloured feathers (blue, purple, golden, green, red) makes it an attractive species to investigate the structural basis of the colouration and to study the connection between the displayed colours and the perception by conspecifics. We analysed the optical properties of the feather barbules, applying spectrophotometry, scatterometry, and electron microscopy. Using the anatomical results, the spectral data can be interpreted by optical modelling. The reflectance spectra of the feathers of male C. helianthea strikingly overlap with the spectral sensitivities of bird photoreceptors, which suggests that the feather and photoreceptor spectra are tuned

Saberes mobilizados pelas gestoras da educação infantil no município de Jaguarão-RS

This paper aims to analyze the knowledge managers mobilize to develop their actions in the Early Childhood Education management in the city of Jaguarão, Brazil. It discusses Early Childhood Education, school management, and school management knowledge. The methodology used focus groups and a semi-structured interview with school managers. Our analysis highlights the absence of room for dialogue and the need of it in carrying out management work. We found that managers describe, through the interviews, epistemological knowledge, experiential knowledge, and knowledge produced in practice and reflection along with their actions.La investigación tuvo como objetivo general analizar los saberes que los gestores movilizan para desarrollar sus acciones en la gestión de la Educación Infantil en el municipio de Jaguarão-RS. Discute la Educación Infantil, la gestión escolar y los conocimientos de gestión escolar. Como instrumento metodológico se utilizó el grupo focal y la entrevista semiestructurada a los directivos. En el análisis se destaca la ausencia de espacios de diálogo y la necesidad de los mismos en la realización del trabajo de gestión. En las consideraciones finales, se señala que en todo momento los gestores describen en su accionar el saber del saber, el saber vivencial y el saber que se produce en la práctica y en la reflexión sobre ella.A pesquisa teve como objetivo geral analisar os saberes que as gestoras mobilizam para desenvolver suas ações na gestão da Educação Infantil no município de Jaguarão-RS. Discute a Educação Infantil, a gestão escolar e os saberes da gestão escolar. Como instrumento metodológico, foram utilizados o grupo focal e a entrevista semiestruturada com as gestoras. Na análise, destacam-se a ausência dos espaços de diálogos e a necessidade destes na realização do trabalho de gestão. Nas considerações finais, aponta-se que em todos os momentos as gestoras descrevem nas suas ações os saberes do conhecimento, os saberes experienciais e os saberes que são produzidos na prática e na reflexão sobre ela

Propuesta de un sistema de contabilidad de costos para la empresa pesquera Alpesca SAC

El presente trabajo de investigación es el resultado de nuestras experiencias adquiridas en nuestros actuales centros de trabajo, como parte de la observación de la forma de costeo del producto terminado en una empresa industrial, tratando de plantear una solución al mismo aplicando los conocimientos recibidos de la universidad institución formadora y parte de ellos adquiridos por el enriquecimiento de la experiencia en el día a día de nuestras labores. La finalidad del presente trabajo es dar a conocer la importancia de un sistema de contabilidad de costos en una empresa industrial, cubriendo en forma integral las necesidades de información del ente en lo que hace a la actividad de producción de bienes y servicios, vinculando los recursos utilizados con los productos obtenidos. En el actual marco en el que se desenvuelven las organizaciones económicas y teniendo en cuenta las tendencias que se vislumbran para el nuevo siglo muchas de las cuales ya son aplicadas hoy en empresas de vanguardia, emerge la necesidad de información como principal herramienta para la conducción empresarial. Hoy en día un adecuado sistema de información de costos se ha convertido en una herramienta básica de contabilidad

Hacia un modelo sinérgico : La apertura de los modelos de interacción de Rokeby

Rokeby D. (1995) en Espejos transformantes: subjetividad y control en los medios interactivos realiza una clasificación de los modos de interacción en obras interactivas haciendo énfasis en la subjetividad del usuario respecto a la obra. Proponemos sumar a las categorías de dicho autor, un modelo de interacción que se asiente en la sinergia e incorpore la idea de intersubjetividad donde el esquema obra-usuarios, sea superado por el esquema obra-usuarios-intersubjetividad. El modelo sinérgico entiende que la acción coordinada de dos o más usuarios produce un resultado mayor que el alcanzado por la acción individual. La interfaz y el programa emergen como componentes fundamentales en el diseño de estos casos, ya que posibilitan o no la participación de dos o más usuarios en una obra interactiva.Mesa G.Facultad de Bellas Arte

Occupational Exposure to Coal, Genotoxicity, and Cancer Risk

Coal is a heterogeneous mixture containing large quantities of organic and inorganic matter, including carbon, hydrogen, oxygen, sulfur, nitrogen, and organometallic forms. The presence of mineral matter in coal may result in a number of environmental and human health problems related to its mining, preparation, and combustion. During coal mining activities, large quantities of coal dust, ashes, polycyclic aromatic hydrocarbons (PAHs), and heavy metals are released into the environment, forming a complex mixture. This mixture becomes one of the most important occupational risks for the health and safety of workers due to its synergistic, additive, and enhancing effects. Once inside the organism, this cocktail-like mixture can interact with cellular mechanisms related to the production of reactive oxygen species (ROS) and can cause damage in important macromolecules such as DNA, lipids, and proteins. In this review, human populations exposed to coal and coal burning were analyzed. Data from different studies were evaluated in relation to the effect of complex mixture exposure on DNA damage and mechanisms, and the background factors, such as gender, age, or smoking habit. The high temperatures that occur in combustion processes affect the characteristics of the resulting particles. The coal fly ash is released by combustion and its composition varies depending on the coal type and the method of collection used such as electrostatic precipitators. Compounds such as PAHs once activated by the organisms have been shown to have mutagenic and carcinogenic activity due to its ability to form adducts with purines. Moreover, metals that commonly are evaporated during the cooling process increase its toxicity. The particles when inhaled can pass from the alveoli into the bloodstream and affect extrapulmonary organs. Several studies have described the inflammatory cascade that triggers exposure to coal and coal fly ash particles; they have a complex composition capable of generating a persistent inflammatory process, resulting in diseases widely described as emphysema, bronchitis, pneumoconiosis, asthma, and cancer. Several human biomonitoring studies have been conducted evaluating the inflammatory process and the release of cytokines, polymorphisms involved in detoxification mechanisms, different biomarkers associated with occupational exposure, DNA damage, and the influence of oxidative stress in disease development. The relationship between chronic exposure to coal and coal ash particles and cancer is still widely debated. This review gave us a broad assessment about the associated mechanisms between cancer and exposure to coal and different findings around the world

O caso do Cabildo uruguaio e argentino: uma análise sobre os processos de patrimonialização frente as suas representatividades.

O ato de preservar representa o lembrar de uma fase, marco ou ato do passado, o patrimônio assim, atua como testemunho de uma época. Ajuda no processo de identidade de um grupo, formula indicadores da construção social. É a ressignificação das manifestações culturais, tornando-as vivas, ganhando sentido para os indivíduos. O trabalho pretende frente à significação do patrimônio e a produção de discursos, analisar os processos de patrimonialização dos cabildos, presentes desde a época de instalação da localidade, de Montevidéu - Uruguai, e Buenos Aires – Argentina, demonstrando a diferença de posicionamento entre os dois países. Além disso, discorre sobre a influência do patrimônio nos processos de identidade e memória coletivas, que representam uma trajetória histórica e cultural

Relación profesor-estudiante en el aula de inglés como lengua extranjera en un colegio público y uno privado de Bogotá

El presente estudio caracteriza la relación profesor estudiante tanto en una escuela pública como en una privada de Bogotá en el aula de inglés como lengua extranjera. Con el fin de comparar dicha relación en ambas instituciones se recolectaron datos cualitativos y cuantitativos por medio de dos cuestionarios que contienen preguntas con escala tipo Likert y preguntas abiertas. Asimismo, para alcanzar este objetivo se analizaron las siguientes cuatro categorías: la relación profesor-estudiante en la enseñanza y aprendizaje de L2 a partir de autores como Williams y Burden (1999), Manen (1998) y Calderón (2005), la relación profesor-estudiante desde lo cognitivo según Oxford (1990), Oxford (2003) y O’Malley y Chamot (1990), lo social desde Vygotsky (1995), Feuerstein (citado en Williams y Burden, 1999) y el Instituto Cervantes (1997) y lo afectivo a partir de autores como Krashen (1989), Garden (1985), Williams y Burden (1999), Harmer (1991), García (2013) y la Alcaldía Mayor de Bogotá (2013). De esta manera, los resultados muestran que la relación profesor-estudiante y los factores que la componen tienen un impacto en el proceso de enseñanza y aprendizaje de inglés, así como también, que los aspectos que tienen una influencia en esta relación dependen de la cantidad de tiempo que los profesores han pasado con sus estudiantes, qué tanto conocen sobre ellos y sus necesidades y si se tienen en cuenta la dimensión cognitiva, social y afectiva cuando el profesor y los estudiantes interactúan.The present study characterizes the teacher-student relationship in both a public school and a private school in Bogota in the English as a foreign language classroom. In order to compare the aforementioned relationship in both institutions, qualitative and quantitative data was collected by means of two questionnaires that include both likert scale and open questions. Additionally, to achieve this objective the following four categories were analyzed : the teacher-student relationship and L2 learning with authors such as Williams & Burden (1999), Manen (1998) and Calderón (2005), the teacher-student relationship from the cognitive perspective according to Oxford (1990), Oxford (2003) and O’Malley & Chamot (1990), from the social perspective in compliance with Vygotsky (1995), Feuerstein (cited in Williams & Burden, 1999) and the Cervantes Institute (1997) and from the affective view according to authors like Krashen (1989), Gardner (1985), Williams & Burden (1999), Harmer (1991), García (2013) and la Alcaldía Mayor de Bogotá (2013). The results show that the teacher-student relationship and the factors that come along with it have an impact on the English teaching and learning process, as well as, that the aspects that have an influence on this relationship depend on the amount of time teachers have spent with students, how much they know about them and their necessities and if the cognitive, social and affective dimensions are taken into account when teachers and the students interact.Licenciado (a) en Lenguas ModernasPregrad

Efficacy of phage therapy in preclinical models of bacterial infection: a systematic review and meta-analysis.

BACKGROUND Antimicrobial resistance of bacterial pathogens is an increasing clinical problem and alternative approaches to antibiotic chemotherapy are needed. One of these approaches is the use of lytic bacterial viruses known as phage therapy. We aimed to assess the efficacy of phage therapy in preclinical animal models of bacterial infection. METHODS In this systematic review and meta-analysis, MEDLINE/Ovid, Embase/Ovid, CINAHL/EbscoHOST, Web of Science/Wiley, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Google Scholar were searched from inception to Sept 30, 2021. Studies assessing phage efficacy in animal models were included. Only studies that assessed the efficacy of phage therapy in treating established bacterial infections in terms of survival and bacterial abundance or density were included. Studies reporting only in-vitro or ex-vivo results and those with incomplete information were excluded. Risk-of-bias assessment was performed using the Systematic Review Centre for Laboratory Animal Experimentation tool. The main endpoints were animal survival and tissue bacterial burden, which were reported using pooled odds ratios (ORs) and mean differences with random-effects models. The I2 measure and its 95% CI were also calculated. This study is registered with PROSPERO, CRD42022311309. FINDINGS Of the 5084 references screened, 124 studies fulfilled the selection criteria. Risk of bias was high for 70 (56%) of the 124 included studies; therefore, only studies classified as having a low-to-moderate risk of bias were considered for quantitative data synthesis (n=32). Phage therapy was associated with significantly improved survival at 24 h in systemic infection models (OR 0·08 [95% CI 0·03 to 0·20]; I2=55% [95% CI 8 to 77]), skin infection (OR 0·08 [0·04 to 0·19]; I2 = 0% [0 to 79]), and pneumonia models (OR 0·13 [0·06 to 0·31]; I2=0% [0 to 68]) when compared with placebo. Animals with skin infections (mean difference -2·66 [95% CI -3·17 to -2·16]; I2 = 95% [90 to 96]) and those with pneumonia (mean difference -3·35 [-6·00 to -0·69]; I2 = 99% [98 to 99]) treated with phage therapy had significantly lower tissue bacterial loads at 5 ± 2 days of follow-up compared with placebo. INTERPRETATION Phage therapy significantly improved animal survival and reduced organ bacterial loads compared with placebo in preclinical animal models. However, high heterogeneity was observed in some comparisons. More evidence is needed to identify the factors influencing phage therapy performance to improve future clinical application. FUNDING Swiss National Foundation and Swiss Heart Foundation