Journal articles: 'Matice experimentů'

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SANTORUM, N., A. FABARA, F. PILAQUINGA, S. AMPUDIA, E. JARA, and L. MENESES. "EXPERIMENTAL AND COMPUTATIONAL CHARACTERIZATION OF SILVER NANOPARTICLES USING MATICO (Piper aduncum) LEAVES EXTRACT AS REDUCING AGENT." Periódico Tchê Química 15, no. 29 (January 20, 2018): 309–18. http://dx.doi.org/10.52571/ptq.v15.n29.2018.309_periodico29_pgs_309_318.pdf.

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Silver nanoparticles are recognized for numerous physical, biological and pharmaceutical applications. In this study, silver nanoparticles were successfully synthesized by green chemistry alternative reduction method, using Matico (Piper aduncum) leaves extract. The characterization was performed through Ultraviolet/VisibleSpectroscopy to estimatethe particle size; morphology and elemental composition were detected by Scanning Electron Microscopy. Estimated radius was measured by Scanning Transmission Electron Microscopy. The interaction between Matico leaves extract with nanoparticles to determine potential reducing active ingredients was monitored by InfraredSpectroscopy. The reaction yield was determined by Flame Atomic Absorption Spectroscopy. The interaction of clusters of silver nanoparticles (3, 5 and 6 atoms) with quercetin (an active molecule of Molecular Dynamics by Gaussian09 and Abalone programs. The particle size was 13.58±6.25nm. It was found that the nanoparticles are quasi-spherical with 7.2 % of elemental silver and a reaction yield of 96.68 %. The cluster of 6 silver atoms with quercetin was proven to be the most stable complex. Synthesized silver nanoparticles display stability greater than 120 days, confirming that Matico leaves extract is a viable and green reducing agent.Silver nanoparticles would have very good clearance properties because molecular dynamics demonstrated that over a certain period of time, the silver cluster got far away from the quercetin.

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Arroyo, Jorge, Renán Hañari, Aldo Tinco, Deyvis Baca, Lester Domínguez, and Jesús Buendía. "Efecto antihipertensivo del extracto de Piper aduncum ‘matico’ sobre la hipertensión inducida por L-NAME en ratones." Anales de la Facultad de Medicina 73, no. 4 (March 13, 2013): 275. http://dx.doi.org/10.15381/anales.v73i4.1024.

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Introducción: El Piper aduncum es una planta conocida como matico. Se le atribuye efectos antihipertensivo, antiinflamatorio, cicatrizante. Objetivos: Determinar el efecto antihipertensivo del extracto de Piper aduncum ‘matico’, sobre la hipertensión inducida por L-NAME, en ratones. Diseño: Experimental. Lugar: Facultades de Medicina y de Farmacia y Bioquímica, Universidad Nacional Mayor de San Marcos, Lima, Perú. Material biológico: Extracto etanólico de las hojas de Piper aduncum y ratas. Intervenciones: Se utilizó seis grupos de seis ratones Muss musculus cada uno, uno sin hipertensión (control negativo) y cuatro con hipertensión inducida por L-NAME: un control positivo y tres grupos para las dosis de 50, 150 y 300 mg/kg, respectivamente. El tratamiento se realizó por vía oral, una vez por día, durante 25 días. Las mediciones de la presión arterial sistólica (PAS), presión arterial diastólica (PAD) y presión arterial media (PAM) fueron realizadas dos veces por semana (martes y viernes) y se consideró las mediciones entre los días 19 y 23 de iniciado el tratamiento. Principales medidas de resultados: Actividad antihipertensiva. Resultados: En los días 19 y 23 se observó los mejores niveles de presión arterial en el grupo control y los experimentales, correspondiendo a las mediciones 6 y 7. La eficacia antihipertensiva para enalapril fue 24,1 a 20,6%, respectivamente, seguida por matico, entre 24,9 y 13,7% (p<0,05). Conclusiones: En las condiciones experimentales, se demostró la actividad antihipertensiva del extracto etanólico de hojas de Piper aduncum ‘matico’. Palabras clave: Agentes antihipertensivos, matico, hipertensión.

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Eysenck, H. J. "The Prediction of Death from Cancer by Means of Personality/Stress Questionnaire: Too Good to Be True?" Perceptual and Motor Skills 71, no. 1 (August 1990): 216–18. http://dx.doi.org/10.2466/pms.1990.71.1.216.

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Recent work by Grossarth-Maticek and Eysenck has suggested that there are personality traits which in combination can predict cancer in healthy probands with 81% accuracy. Many critics have considered this result “too good to be true” It is shown that earlier studies have given results not very different in accuracy, suggesting that such a criticism is unwarranted.

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Barelli, Maria Cecilia. "El ensayo de una ‘neue Aufklärung’ como preludio de la ‘filosofía experimental’ futura en Nietzsche." Anales del Seminario de Historia de la Filosofía 37, no. 1 (April 23, 2020): 59–71. http://dx.doi.org/10.5209/ashf.61485.

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Nos proponemos indagar la recepción de la Ilustración en Friedrich Nietzsche. Encontramos en sus escritos publicados y póstumos no solo una evaluación o balance crítico de los alcances de este movimiento en sus distintas expresiones, sino también el ensayo de continuar con algunas de sus tareas, a partir de una praxis filosófica de carácter experimental. Consideramos, por lo tanto, que la noción de Aufklärung, con los giros y los matices esbozados por el propio pensador alemán, merecen un renovado y detenido análisis, tanto por los aportes que pueden hacerse en el campo de la exegesis crítica e histórica del corpus nietzscheano, como por la posibilidad de reconstruir, en parte, el modo en que ingresa la corriente ilustrada en la filosofía europea de mediados y segunda mitad del siglo XIX. Palabras clave: Nietzsche-Ilustración-Experimento-Filosofía

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Pachilla, Pablo N. "Swimming alone. The journey as a trans-subjetivization experiment in two tales by Matilde Sanchez." Logos: Revista de Lingüística, Filosofía y Literatura 25, no. 2 (November 2015): 103–13. http://dx.doi.org/10.15443/rl2509.

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POPESCU, Ionel, Lică FLORE, and Albert ARNAU CUBILLO. "DERIVATION OF MASS, STIFFNESS AND DAMPING MATRICES OF A MODEL WING FROM EXPERIMENTAL MODAL DATA." SCIENTIFIC RESEARCH AND EDUCATION IN THE AIR FORCE 19, no. 1 (July 31, 2017): 323–30. http://dx.doi.org/10.19062/2247-3173.2017.19.1.39.

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Boyes, E. D. "High-resolution hot-stage experiments." Proceedings, annual meeting, Electron Microscopy Society of America 47 (August 6, 1989): 626–27. http://dx.doi.org/10.1017/s0424820100155104.

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High resolution electron microscopy provides a powerful method for studying controlled dynamic reaction sequences and the development of microstructures on the atomic scale. Temperatures can be controlled with reasonable accuracy using a standard hot-stage, but at elevated temperatures there is some reduction in the contrast, and stability, of images. It is, of course, essential to minimise the effects, including additional heating, of irradiating the sample with a high voltage electron beam in a high vacuum environment, and to take into account the close proximity of two specimen surfaces in designing experiments. TV imaging techniques, in-situ, relocatable ex-situ and environmental methods are being developed for use with two medium voltage side-entry high resolution TEMs, equipped with complementary chemical and structural microanalytical STEM facilities.TV imaging techniques Dynamic reaction sequences are now mostly viewed with a low-light level TV camera (LLTV) using a thin YAG or YAP pickup screen and recorded on U-matic videotape to facilitate subsequent processing. The results can be improved substantially by using a digital framestore based image processor to enhance the signal to noise ratio of the video signal in realtime. A major element in the SNR is the shot noise statistics of the TEM electron beam.

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Bornaz Acosta, Juan Guillermo, Zenaida Inofuentes Espinoza, Denisse Ethiel Tito Aquino, and Vanessa Lissete Bornaz Arenas. "Efecto antimicrobiano In vitro del extracto etanólico al 40 % de Piper aungustifolium (matico) sobre Enterococcus faecalis." Revista Médica Basadrina 13, no. 2 (January 7, 2020): 12–18. http://dx.doi.org/10.33326/26176068.2019.2.876.

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Enterococcus faecalis es considerada una cepa con gran capacidad de adaptación y tolerancia a las condiciones de un medio adverso, siendo difícil su erradicación en una endodoncia. Objetivo: Estudiar el efecto antimicrobiano del extracto de Piper aungustifolium, más conocida en nuestro medio como matico sobre la cepa Enterococcus faecalis. Material y Métodos: Se realizó una siembra de la cepa ATCC 29212 (Enterococcus faecalis) en placas con Agar Cerebro Corazón BHI, luego se colocó en las superficies de sensidiscos de 5 mm de diámetro embebidos con las soluciones del matico, y se hizo 3 pozos de 5 mm de diámetro por 6 mm de profundidad, utilizándose una puntera descartable de 1 ml, previamente tratada y esterilizada para colocar el hidróxido de calcio como grupo control y Piper aungustifolium como grupo experimental. Para cada grupo se utilizaron 24 muestras; luego se incubaron a 37o C, a las 24, 48, 72 horas y 7 días, registrándose el diámetro de los halos. Resultados: Los promedios de la medida del halo inhibitorio de Piper aungustifolum (matico) fueron menores que la del hidróxido de calcio. Se aplicó posteriormente T de Student (p <0,05) , dando como resultado diferencia estadísticamente significativa entre los datos obtenidos para las tomas a las 24, 72 y 7 días, exceptuando aquellas a las 48 horas donde no hubo diferencia entre ambas sustancias. Conclusiones: La Piper aungustifolum, demostró tener efecto antibacteriano frente al Enterococcus faecalis, sus medidas fueron variadas y progresivas a través de tiempo.

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Maya-Gress, Kristian Freyri, Raúl Villafuerte-Segura, Hugo Romero-Trejo, and Miguel Ángel Bernal-Reza. "Puesta en operación y modelado de un cuatrirotos: Matrice 100 de DJI." Pädi Boletín Científico de Ciencias Básicas e Ingenierías del ICBI 9, no. 17 (July 5, 2021): 67–75. http://dx.doi.org/10.29057/icbi.v9i17.6462.

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En la actualidad el empleo de vehículos aéreos no tripulados (VANT) es muy recurrente en diversas aplicaciones industriales, comerciales, ambientales, académicas, investigación, entre otras. Uno de los temas centrales de estos vehículos es su correcta manipulación/control en ausencia del ser humano. Sin embargo, esto no se puede alcanzar sin la puesta en operación y el empleo de modelos matemáticos. En este manuscrito se presenta la puesta en operación del VANT conocido como Matrice 100 de DJI, además del empleo de las técnicas más recurrente encontradas en la literatura para la obtención de su modelo matemático correspondiente. Este VANT es una plataforma experimental con base de fibra de carbón y cuatro rotores, cuenta con un software (simulador de vuelo) de arquitectura abierta para la comunicación/manipulación; desarrollado en el entorno integral libre Android Studio. Para el modelo matemático se considera una configuración en CRUZ y se emplea la metodología propuesta por Euler-Lagrange para describir las dinámicas traslacionales y rotacionales caracterizando las energías cinéticas y potenciales involucradas, teniendo como resultado un modelo no lineal subactuado de orden doce. Para corroborar el buen funcionamiento y la manipulación de la plataforma experimental; así como su correspondencia con el modelo matemático, se presentan simulaciones desarrolladas en Simulink-Matlab y el simulador de vuelo del fabricante, además de pruebas experimentales. Para lo anterior, se emplea un control clásico PD sintonizado solo para alcanzar una altura z en el VANT (considerando solo dinámicas traslacionales).

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Abduchalek, Budi, Aunu Rauf, and Pudjianto . "KUTU PUTIH SINGKONG, PHENACOCCUS MANIHOTI MATILE-FERRERO (HEMIPTERA: PSEUDOCOCCIDAE): PERSEBARAN GEOGRAFI DI PULAU JAWA DAN RINTISAN PENGENDALIAN HAYATI." JURNAL HAMA DAN PENYAKIT TUMBUHAN TROPIKA 17, no. 1 (May 3, 2017): 1. http://dx.doi.org/10.23960/j.hptt.1171-8.

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Cassava mealybug, Phenacoccus manihoti Matile-Ferrero (Hemiptera: Pseudococcidae): Geographic distribution in Java and initiation of biological control. Cassava mealybug, Phenacoccus manihoti Matile-Ferrero (Hemiptera: Psedococcidae), is a recently introduced pest in Indonesia. Parasitoid Anagyrus lopezi (De Santis) (Hymenoptera: Encyrtidae) was imported to control the pest. Studies were conducted to determine geographic distribution of P. manihoti throughout Java, and to evaluate the potential of the parasitoid as a biological control agent. Geographic distribution of the pest was determined through field survey, whereas evaluation of the parasitoid was studied through cage experiment and field release. Our survey revealed that the cassava mealybug has spread throughout Java. Heavy infestations caused shortened and distorted stems, complete defoliation, and stunted growth. In cages containing only mealybugs, all cassava plants (100%) died after two months. Whereas in cages containing both mealybugs and three pairs of parasitoid, rate of parasitization was 25% and plant mortality 20%. Parasitoids released in the field were able to survive, reproduce, and establish under Bogor climatic condition. These might indicate that parasitoid A. lopezi is a potential natural enemy to be used in biological control program of the cassava mealybug.

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Cáceres Manrique, Flor de María, Gloria Molina Marín, and Myriam Ruíz Rodríguez. "Maternidad: un proceso con distintos matices y construcción de vínculos." Aquichan 14, no. 3 (September 1, 2014): 316–26. http://dx.doi.org/10.5294/aqui.2014.14.3.4.

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Objetivo: comprender los significados de la maternidad para las gestantes, con el fin de orientar la promoción de la salud materno- infantil. Materiales y métodos: investigación cualitativa, con sustento teórico en el interaccionismo simbólico y el método de la teoría fundamentada. Previo consentimiento informado se realizaron entrevistas en profundidad a 18 gestantes mayores de 14 años, de diferentes estratos socioeconómicos, residentes en Bucaramanga (Colombia). También se observaron sus interacciones con otras gestantes y con personal de salud en las instituciones donde reciben atención prenatal. La información fue analizada paralelamente con su recolección mediante codificación abierta y categorización basada en el método de comparación constante y muestreo teórico, hasta lograr la saturación de las categorías. Los resultados se validaron en grupos focales con gestantes. Resultados: emergieron categorías que dan cuenta de la maternidad como proceso, con preocupación, responsabilidad, adaptación/acomodación y como una experiencia positiva. Como categoría central surgió la maternidad como proceso transformador con experiencias positivas y construcción de vínculos. Discusión: para las gestantes, la maternidad tiene distintos significados y matices, principalmente desde sus componentes socioculturales, aspectos que se deben tener en cuenta para orientar la promoción de la salud materno-infantil y el cuidado materno. Conclusiones: la maternidad es un proceso complejo y de transformación personal que ayuda a las gestantes a formar vínculos con su hijo, con la pareja y con los familiares que la apoyan. Durante esta experimentan sentimientos encontrados de alegría y satisfacción, junto con preocupación y angustia por los retos que implica la maternidad. Entender este proceso orienta el quehacer de los profesionales de la salud hacia una atención prenatal armonizada con las expectativas de la gestante.

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Mohamad, Barhm, Jalics Karoly, Andrei Zelentsov, and Salah Amroune. "A comparison between hybrid method technique and transfer matrix method for design optimization of vehicle muffler." FME Transactions 49, no. 2 (2021): 494–500. http://dx.doi.org/10.5937/fme2102494m.

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Hybrid mufflers are now commonly equipped to decrease vehicle noise and are a crucial tool for regulation of the acoustic system. In order to ensure optimum engine efficiency, the system is intended to dump the strength of the acoustic pulses generated from the engine, and the back pressure created by these systems must be held to a minimum. Typically, modern mufflers have a complex structure of chambers and flow paths. There are a number of mechanisms for sound dampening that operate to silence the sound flowing through a muffler and piping device. This research introduces an important approach to optimize the transmission loss of hybrid muffler Formula student race car (FS) by using both experimental and analytical methods. For this analysis, two methods of calculation were chosen. The muffler has a complex partition located within the muffler chamber, which is a perforated pipe. For the creation of the Finite Element Analysis (FEA) model in AVL BOOST solver and another commercial advanced design software, the muffler CAD file was developed. Experimental measurements using a two-load method validated the FEA model. Reliable tests were conducted to verify the design parameters and optimize the muffler's transmission loss (TL) after the model was checked. The findings of experimental and machine analysis are included in the paper. For different measurement methods, recommendations are made for achieving optimum transmission loss curves.

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Liu, Yan, Hejun Du, and Shao Wang. "P-HDI-02 ESTIMATION OF SUSPENSION STIFFNESS MATRICES WITH EXPERIMENTS(Head/Disk Interface and Tribology,Technical Program of Poster Session)." Proceedings of JSME-IIP/ASME-ISPS Joint Conference on Micromechatronics for Information and Precision Equipment : IIP/ISPS joint MIPE 2009 (2009): 351–52. http://dx.doi.org/10.1299/jsmemipe.2009.351.

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Ginsburg, Faye. "INDIGENOUS MEDIA FROM U-MATIC TO YOUTUBE: MEDIA SOVEREIGNTY IN THE DIGITAL AGE." Sociologia & Antropologia 6, no. 3 (December 2016): 581–99. http://dx.doi.org/10.1590/2238-38752016v632.

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Abstract This article covers a wide range of projects from the earliest epistemological challenges posed by video experiments in remote Central Australia in the 1980s to the emergence of indigenous filmmaking as an intervention into both the Australian national imaginary and the idea of world cinema. It also addresses the political activism that led to the creation of four national indigenous television stations in the early 21st century: Aboriginal People's Television Network in Canada; National Indigenous Television in Australia; Maori TV in New Zealand; and Taiwan Indigenous Television in Taiwan); and considers what the digital age might mean for indigenous people worldwide employing great technological as well as political creativity.

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Miracle, Daniel B., Mu Li, Zhaohan Zhang, Rohan Mishra, and Katharine M. Flores. "Emerging Capabilities for the High-Throughput Characterization of Structural Materials." Annual Review of Materials Research 51, no. 1 (July 26, 2021): 131–64. http://dx.doi.org/10.1146/annurev-matsci-080619-022100.

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Structural materials have lagged behind other classes in the use of combinatorial and high-throughput (CHT) methods for rapid screening and alloy development. The dual complexities of composition and microstructure are responsible for this, along with the need to produce bulk-like, defect-free materials libraries. This review evaluates recent progress in CHT evaluations for structural materials. High-throughput computations can augment or replace experiments and accelerate data analysis. New synthesis methods, including additive manufacturing, can rapidly produce composition gradients or arrays of discrete alloys-on-demand in bulk form, and new experimental methods have been validated for nearly all essential structural materials properties. The remaining gaps are CHT measurement of bulk tensile strength, ductility, and melting temperature and production of microstructural libraries. A search strategy designed forstructural materials gains efficiency by performing two layers of evaluations before addressing microstructure, and this review closes with a future vision of the autonomous, closed-loop CHT exploration of structural materials.

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Chalupa, V. "In vitro propagation of mature trees of Sorbus aucuparia L. and field performance of micropropagated trees." Journal of Forest Science 48, No. 12 (May 22, 2019): 529–35. http://dx.doi.org/10.17221/11923-jfs.

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The influence of tree age, explant source and genotype on micropropagation of mature trees of Sorbus aucuparia has been investigated. Experiments demonstrated the feasibility to use juvenile parts of mature trees for in vitro propagation of selected genotypes. Explants from lower branches and from epicormic shoots of mature trees exhibited high multiplication coefficients of microshoots cultured on modified MS agar nutrient medium supplemented with cytokinin (BA, TDZ) and auxin (IBA). Microshoots produced from juvenile parts of mature trees exhibited good rooting response and produced plants were well adapted to grow in forest soils. The survival of micropropagated trees planted in experimental plots was high and losses during winter were low. Height and diameter increments of micropropagated trees originated from juvenile parts of mature trees were considerable and their dimensions after five years of growth were comparable with the dimensions of trees originated from seeds.

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Afantitis, Antreas, Andreas Tsoumanis, and Georgia Melagraki. "Enalos Suite of Tools: Enhancing Cheminformatics and Nanoinfor - matics through KNIME." Current Medicinal Chemistry 27, no. 38 (November 12, 2020): 6523–35. http://dx.doi.org/10.2174/0929867327666200727114410.

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Drug discovery as well as (nano)material design projects demand the in silico analysis of large datasets of compounds with their corresponding properties/activities, as well as the retrieval and virtual screening of more structures in an effort to identify new potent hits. This is a demanding procedure for which various tools must be combined with different input and output formats. To automate the data analysis required we have developed the necessary tools to facilitate a variety of important tasks to construct workflows that will simplify the handling, processing and modeling of cheminformatics data and will provide time and cost efficient solutions, reproducible and easier to maintain. We therefore develop and present a toolbox of >25 processing modules, Enalos+ nodes, that provide very useful operations within KNIME platform for users interested in the nanoinformatics and cheminformatics analysis of chemical and biological data. With a user-friendly interface, Enalos+ Nodes provide a broad range of important functionalities including data mining and retrieval from large available databases and tools for robust and predictive model development and validation. Enalos+ Nodes are available through KNIME as add-ins and offer valuable tools for extracting useful information and analyzing experimental and virtual screening results in a chem- or nano- informatics framework. On top of that, in an effort to: (i) allow big data analysis through Enalos+ KNIME nodes, (ii) accelerate time demanding computations performed within Enalos+ KNIME nodes and (iii) propose new time and cost efficient nodes integrated within Enalos+ toolbox we have investigated and verified the advantage of GPU calculations within the Enalos+ nodes. Demonstration data sets, tutorial and educational videos allow the user to easily apprehend the functions of the nodes that can be applied for in silico analysis of data.

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Matus Lazo, Roger. "Docente de la UNAN-Managua publica el "Breve diccionario de la lengua popular en hablantes de Managua"." Revista Lengua y Literatura 3, no. 2 (July 21, 2017): 46–47. http://dx.doi.org/10.5377/rll.v3i2.9410.

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Las palabras sirven para representar las cosas y para expresar las ideas y sentimientos. Pero como las cosas no siempre permanecen estables y las ideas y sentimientos experimentan variación en sus matices y por tanto movimientos de sentido, las palabras que los designan tienen que reflejar estos cambios semánticos. Es lo que nos logra demostrar la maestra Francis Mendoza Morán con este Breve diccionario de la lengua popular en hablantes de Managua, Nicaragua, su más reciente obra lexicográfica, que viene a enriquecer y fortalecerlos estudios léxico-semánticos en el español de uso actual en nuestro país.

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Listiyono, Listiyono, Nurhadi Nurhadi, and Khambali Khambali. "ANALISIS DIAMETER KAWAT SPRING DAN PANJANG LOWER MOUNTING SUSPENSI BELAKANG MOTOR MATIC." Jurnal Energi dan Teknologi Manufaktur (JETM) 4, no. 01 (June 30, 2021): 32–36. http://dx.doi.org/10.33795/jetm.v4i01.67.

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The stability of the vehicle / motorbike is also determined by the suspension. Usually the suspension on the motor is installed right-left symmetrically. This is so that the vehicle load is evenly distributed if there is a shock / sudden load. But development and need negate each other. Currently, the development of automatic motorbikes is quite rapid. This motorbike is designed to be sleek and nimble and easy to maintain. Therefore, the rear suspension of the automatic motorbike is installed on only one side. And this usually occurs during sharp turns and high speeds and if you go through uneven roads. For this reason, it is necessary to design the right suspension so that the vehicle can maintain stability even when turning or passing uneven roads. This instability is due to the large vibration of the vehicle. The objectives of this study are 1. To determine the effect of the size of the spring wire and the length of the mounting on the vibration frequency. 2. Find the diameter of the spring wire and the length of the mounting that will give a good vibration frequency. This study uses the Desaign Of Experiment method. Desaign factor 2, namely diameter of spring wire and length of muoting. Level 3 factor is 6 mm, 7 mm and 8 mm diameter. Mounting lengths of 30 mm, 35 mm and 40 mm. Data analysis using MINITAB program. From the analysis, it is found that 1. The diameter of the spring coil wire and the mounting has a significant effect on the vibration frequency of the automatic motor. 2. The best size for wire spring diameter for coil spring motor matic is 7 mm, while the thickness of the mounting is 37 mm. Keywords: Suspension, Motorcycle, Spring Wire. Lower Mounting, vibration frequency

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Matich, Olga. "Poetics of Disgust: To Eat and Die in Andrei Belyi's Petersburg." Slavic Review 68, no. 2 (2009): 284–307. http://dx.doi.org/10.2307/27697959.

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The article examines the aversive emotion of disgust and its deployment in the visual arts and in the premier Russian modernist novel, Andrei Belyi's Petersburg, which has not been considered in regard to its affective poetics before. Based on recent studies of the emotions in cultural history and theory, it explores the philosophical, psychological, and aesthetic aspects of disgust as a response to something viscerally and/or morally repugnant. The emotion, induced by the experience seen or imagined close up, provokes the observer's recoil as defined by cultural norms. As such, disgust is performative in spatial terms. Olga Matich argues that movement away from the loathsome image or idea affords the possibility of making the experience cognitively readable or legible, that disgust creates a space in which the individual negotiates her emotional as well as moral response. Yet she claims that aesthetically—and in certain instances ethically—disgust, which is always about the boundaries of the permissible, is also liberating: it offers society, its artists, and their consumers the opportunity to transgress established norms. Through extensive close readings of Petersburg, Matich shows that Belyi's experimental novel does precisely that, challenging the reader not to avert her readerly gaze from that which is unsettling and to appreciate, even to delight in, his shocking metamorphic image-making. She calls Petersburg a modernist exemplar of baroque aesthetics, characterized by excessive affect and grotesque representation, especially of the corpse, invoking the transience of life and dissolution of form.

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White, Rebecca J., and Corey A. Hammer. "Quiz-o-Matic: A free Web-based tool for construction of self-scoring on-line quizzes." Behavior Research Methods, Instruments, & Computers 32, no. 2 (June 2000): 250–53. http://dx.doi.org/10.3758/bf03207791.

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Gazola, Diego, Vanda Pietrowski, Claudemir Zucareli, Diandro Ricardo Barilli, and Rudiney Ringenberg. "Management and population fluctuation of cassava mealybug Phenacoccus manihoti Matile-Ferrero (Hemiptera: Pseudococcidae)." Semina: Ciências Agrárias 40, no. 5 (July 4, 2019): 1829. http://dx.doi.org/10.5433/1679-0359.2019v40n5p1829.

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Cassava is one of the main foods in Brazil, playing a key role in the diet of several communities. In the Central-Southern region of Brazil, several pests are associated with cassava, among which the cassava mealybug stands out due to its high potential for damage. The aim of the present study was to evaluate the population dynamics and the effect of pruning and different cassava management on the developmental stages of mealybug, Phenacoccus. manihoti. The experiment was conducted in Santa Monica, PR, with ‘Cauiá’ cultivar, involving a randomized complete block design with four replications and six treatments: 1) No pruning: intact plants, 2) Pruning soil: pruned close to the soil without plant material, 3) Pruning at 15 cm: conventional pruning at 15 cm of the soil with vegetative material, 4) Pruning + branches: conventional pruning, with the middle portion of the plant in the plot and removal of the apical region of the plant, 5) Pruning + apical: conventional pruning, with the removal of the middle portion of the plant and retaining the apical parts of the plant, and 6) Pruning - branches - apical: conventional pruning, with the removal of the middle and apical portions of the plant. After 7-days of pruning, the number of eggs, nymphs, and adults were counted, and the population variation was monitored at weekly interval for a month. For the insect count, four sites were randomly chosen in a zigzag manner within each plot and four plants were evaluated, totaling 16 plants per plot. Based on the counts, the percentage of plants with eggs, nymphs, and adults was calculated. The data of the variables were transformed by ?(x+5), subjected to analysis of variance and Scott Knot test (5%). The percentage of plants with egg mass and adults of P. manihoti was highest in plots that had no pruning. The pruning close to the soil combined with the removal of vegetative material resulted in plants with fewest eggs of P. manihoti. Removal of the apical region portion of the cassava plant reduced the number of P. manihoti nymphs and adults.

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Brewer, Matthew J., and Craig B. Clements. "Meteorological Profiling in the Fire Environment Using UAS." Fire 3, no. 3 (July 31, 2020): 36. http://dx.doi.org/10.3390/fire3030036.

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With the increase in commercially available small unmanned aircraft systems (UAS), new observations in extreme environments are becoming more obtainable. One such application is the fire environment, wherein measuring both fire and atmospheric properties are challenging. The Fire and Smoke Model Evaluation Experiment offered the unique opportunity of a large controlled wildfire, which allowed measurements that cannot generally be taken during an active wildfire. Fire–atmosphere interactions have typically been measured from stationary instrumented towers and by remote sensing systems such as lidar. Advances in UAS and compact meteorological instrumentation have allowed for small moving weather stations that can move with the fire front while sampling. This study highlights the use of DJI Matrice 200, which was equipped with a TriSonica Mini Wind and Weather station sonic anemometer weather station in order to sample the fire environment in an experimental and controlled setting. The weather station was mounted on to a carbon fiber pole extending off the side of the platform. The system was tested against an RM-Young 81,000 sonic anemometer, mounted at 6 and 2 m above ground levelto assess any bias in the UAS platform. Preliminary data show that this system can be useful for taking vertical profiles of atmospheric variables, in addition to being used in place of meteorological tower measurements when suitable.

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Bentchikou, Mohamed, Salah Hanini, Kamel Silhadi, and Amor Guidoum. "Élaboration et étude d'un mortier composite à matrice minérale et fibres cellulosiques : application à l'isolation thermique en bâtiment." Canadian Journal of Civil Engineering 34, no. 1 (January 1, 2007): 37–45. http://dx.doi.org/10.1139/l06-149.

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This paper presents an experimental study of the effect of adding recycled cellulose fibres on physical, thermal, and mechanical properties of lightweight concrete composites. Results show an important decrease of density and thermal conductivity with an increase of fibre content. Compression and flexural strength decreased with fibre content, but remained within the standard range for hollow non-load-bearing concrete masonry (ASTM C109/C 109-95) for the maximum fibre content (15%).Key words: mortar composite, mineral matrix, cellulose fibre, thermal conductivity, mechanical strengths.

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25

Lucero, Miriam. "G. Deleuze – M. Foucault. Acerca de la relación entre genealogía, arqueología y rizoma como métodos filosóficos." Nuevo Itinerario, no. 8 (July 9, 2013): 174. http://dx.doi.org/10.30972/nvt.081736.

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En este trabajo indagamos las perspectivas metodológicas de G. Deleuze y M. Foucault, y la vinculación que ambos tienen con el concepto nietzscheano de genealogía. Sostenemos como hipótesis que pese a la estrecha vinculación entre sus pensamientos, es el marco de la problemática metodológica donde sus pensamientos adquieren nuevos matices, producto de la apuesta deleuziana por la invención y el lugar privilegiado que en su producción le otorga al arte. Revisaremos para ello, en lo que respecta a Foucault el giro que experimenta su pensamiento entre los análisis arqueológicos y los genealógicos, mientras que en Deleuze analizaremos su método predilecto: el rizoma. Advertimos que la puesta en conjunción de ambos pensamientos desde su perspectiva metodológica puede generar nuevas aristas a la comprensión de ambos autores, y delimitar el carácter políticamente inédito de sus miradas.

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Pharr, George M., Erik G. Herbert, and Yanfei Gao. "The Indentation Size Effect: A Critical Examination of Experimental Observations and Mechanistic Interpretations." Annual Review of Materials Research 40, no. 1 (June 2010): 271–92. http://dx.doi.org/10.1146/annurev-matsci-070909-104456.

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Arroyo, Jorge, Oscar Herrera Calderón, Roberto Chávez Asmat, Edith Ventura, Jesús Buendía, José Pacheco, and Robert Palomino. "Efecto antitumoral in vitro del aceite esencial de Piper aduncum L. (matico) y su toxicidad oral en ratones." Anales de la Facultad de Medicina 75, no. 1 (April 15, 2014): 13. http://dx.doi.org/10.15381/anales.v75i1.6938.

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Introducción: Piper aduncum (matico) es una especie utilizada por sus propiedades medicinales en desórdenes gastrointestinales y genitourinarios. Objetivos: Evaluar el efecto antitumoral del aceite esencial de Piper aduncum (matico) in vitro en siete líneas celulares tumorales humanas y determinar la toxicidad oral en ratones. Diseño: Experimental. Institución: Facultad de Medicina, Universidad Nacional Mayor de San Marcos, Lima, Perú. Material biológico: Líneas celulares tumorales humanas H460, DU-145, ME-180, K562, HT-29, MCF 7, M14, K562; fibroblastos normales de ratón 3T3 y ratones albinos machos Balb/C53. Intervenciones: Las líneas celulares fueron expuestas a cuatro concentraciones del aceite esencial de P. aduncum y 5-fluorouracilo (5-FU). Para la toxicidad oral se utilizó ratones albinos machos Balb C/53 de 40 días post destete, a cinco dosis de tratamiento, evaluándose el número de muertes en cada dosis. Principales medidas de los resultados: Porcentaje de inhibición del crecimiento celular (IC50), dosis letal 50 (DL50). Resultados: El aceite esencial mostró IC50 mayor a 250 ug/mL para las líneas celulares M-14 (r = -0,99; p < 0,01), DU-145 (r = 0,99; p < 0,01), ME-180 (r = -0,99; p < 0,01). Para líneas celulares tumorales H460 (r = -0,99; p < 0,01), MCF-7 (r = -0,99; p < 0,01), K562 (r = -0,99; p < 0,01), HT-29 (r = -0,99; p < 0,01), los niveles de IC50 estuvieron entre 20 ug/mL y 250 ug/mL. DL50 > 2 000 mg /kg. Conclusiones: El aceite esencial de P. aduncum no presentó efecto antitumoral in vitro para las siete líneas celulares tumorales humanas y no fue tóxico.

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Blanco González, Antonio, and Ángel Esparza Arroyo. "Conectividad en la Edad del Bronce del occidente de la península ibérica. Examinando la relación entre sitios y vías pecuarias mediante SIG." Trabajos de Prehistoria 76, no. 1 (June 4, 2019): 67. http://dx.doi.org/10.3989/tp.2019.12226.

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Este artículo evalúa de forma crítica una vieja hipótesis de la Prehistoria de la península ibérica que ha quedado sin refutar: la que relaciona los sitios de Cogotas I (1850-1100 cal AC) con la trashumancia. Se propone un experimento en una amplia franja del occidente ibérico coincidente con la denominada Vía de la Plata: la medición con SIG de la distancia lineal entre 176 sitios de Cogotas I y las vías pecuarias, concebidas como síntomas materiales de hábitos inveterados. Los resultados, estadísticamente significativos con matices regionales, indican que casi un tercio de los casos –el 27,3 %– se encuentran a menos de 500 m. Evitamos relacionar esa proximidad con la trashumancia, la subordinación centro-periferia o el tráfico de objetos elitistas. Entendemos tal pauta como indicio del interés de los grupos estudiados, entre otras decisiones locacionales, por participar en la circulación de personas, animales y cargas, conforme al modelo de comunidades políticas paritarias (peer polity interaction).

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Buryakov, N. P., M. A. Buryakova, A. S. Zaikina, I. A. Kasatkina, and D. E. Aleshin. "Efficiency of protein concentrate application in the rations of highly productive cows." Kormlenie sel'skohozjajstvennyh zhivotnyh i kormoproizvodstvo (Feeding of agricultural animals and feed production), no. 2 (February 1, 2021): 15–25. http://dx.doi.org/10.33920/sel-05-2102-02.

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The association between science and production is gradually developing due to the arrival of new information and discoveries about the composition of feed and the transformation of nutrients in the body of cows. One of the most important links in the formation of animal productivity during lactation is the use of new feed products and feed additives in feeding. The results of scientific and economic experiment on the use of protein concentrate “Agro-Matic” in feeding of highly productive lactating cows of Ayrshire breed are contained the article. The inclusion of protein concentrate “AgroMatic” in the daily rations of lactating cows in the amount of 1,0 and 1,5 kg/head/day increases the level of indigestible protein by 6,1 and 8,9 %, respectively. The use of protein concentrate in the amount of 1,5 kg in cows feeding helps to increase the digestibility of nutrients in rations the quality of milk and the productivity of cows. When feeding protein concentrate in the amount of 1,5 kg the milk productivity of cows during the period of increasing the milk yield was 4297,5 kg of milk, the yield of essential and dispensable amino acids with milk was significantly higher. The yield of milk protein in cows that received protein concentrate in the ration in the amount of 1,0 kg was 137,7 kg, and when using 1,5 kg – 141,4 kg, which was signifi cantly higher than in the control group by 10,2 and 13,6 kg, respectively. The use of protein concentrate “Agro-Matic” in the ration had a benefi cial eff ect on the digestibility of protein. The digestibility of raw protein of the feed mixture with the inclusion of 1,5 kg of protein concentrate was 71,1 % compared to 68,0 % in the basic ration, which are used at the Maysky complex in the “Plemzavod Maysky”

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Mawrence, Raphael, Sandra Munniks, and João Valente. "Calibration of Electrochemical Sensors for Nitrogen Dioxide Gas Detection Using Unmanned Aerial Vehicles." Sensors 20, no. 24 (December 20, 2020): 7332. http://dx.doi.org/10.3390/s20247332.

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For years, urban air quality networks have been set up by private organizations and governments to monitor toxic gases like NO2. However, these networks can be very expensive to maintain, so their distribution is usually widely spaced, leaving gaps in the spatial resolution of the resulting air quality data. Recently, electrochemical sensors and their integration with unmanned aerial vehicles (UAVs) have attempted to fill these gaps through various experiments, none of which have considered the influence of a UAV when calibrating the sensors. Accordingly, this research attempts to improve the reliability of NO2 measurements detected from electrochemical sensors while on board an UAV by introducing rotor speed as part of the calibration model. This is done using a DJI Matrice 100 quadcopter and Alphasense sensors, which are calibrated using regression calculations in different environments. This produces a predictive r-squared up to 0.97. The sensors are then calibrated with rotor speed as an additional variable while on board the UAV and flown in a series of flights to evaluate the performance of the model, which produces a predictive r-squared up to 0.80. This methodological approach can be used to obtain more reliable NO2 measurements in future outdoor experiments that include electrochemical sensor integration with UAV’s.

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Bishop, A. R. "Multiscale Patterning from Competing Interactions and Length Scales." Annual Review of Materials Research 50, no. 1 (July 1, 2020): 207–27. http://dx.doi.org/10.1146/annurev-matsci-081519-050045.

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We live in a research era marked by impressive new tools powering the scientific method to accelerate the discovery, prediction, and control of increasingly complex systems. In common with many disciplines and societal challenges and opportunities, materials and condensed matter sciences are beneficiaries. The volume and fidelity of experimental, computational, and visualization data available, and tools to rapidly interpret them, are remarkable. Conceptual frameworks, including multiscale, multiphysics modeling of this complexity, are fueled by the data and, in turn, guide directions for future experimental and computational strategies. In this spirit, I discuss the importance of competing interactions, length scales, and constraints as pervasive sources of spatiotemporal complexity. I use representative examples drawn from materials and condensed matter, including the important role of elasticity in some technologically important quantum materials.

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Karna, Sunil, Christopher Saunders, Roma Karna, Deepa Guragain, Sanjay Mishra, and Priya Karna. "Hydrothermal synthesis of carbon and sulfur mono-doped sodium tantalates." PeerJ Materials Science 2 (October 23, 2020): e10. http://dx.doi.org/10.7717/peerj-matsci.10.

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A set of experiments was conducted to synthesize doped and undoped sodium tantalates with carbon and sulfur in energy efficient single-step hydrothermal process. Undoped sodium tantalate nanocubes were synthesized at 140 °C and doped one at 180 °C for 12 h in rich alkaline atmosphere. The sizes of undoped, carbon-doped, and sulfur-doped sodium tantalate nanocubes were 38 nm, 45 nm, and 40 nm, respectively. The morphological, elemental, compositional, structural, thermal, and photophysical properties of as-synthesized doped and undoped sodium tantalate (NaTaO3) were characterized using scanning electron microscope (SEM), energy dispersive x-ray spectroscope (EDS), Raman spectroscopy, X-ray powder diffraction (XRD), thermal gravimetric analysis (TGA), Fourier transform infrared spectrophotometer (FTIR), and UV-vis spectrophotometer. The sulfur doped NaTaO3 shows a higher photocatalytic activity in degradation of methylene blue than carbon doped and the undoped NaTaO3. The band gaps of undoped NaTaO3, carbon doped c-NaTaO3, and sulfur doped s-NaTaO3 were calculated to be 3.94 eV, 3.8 eV, and 3.52 eV, respectively using Tauc plot.

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33

CAMINO CONDE, María. "La expresión del absurdo en El extranjero de Albert Camus y Absolución de Luis Landero: estudio comparativo." Creneida. Anuario de Literaturas Hispánicas 5 (December 30, 2017): 346–71. http://dx.doi.org/10.21071/calh.v5i.10377.

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Al adquirir conciencia del paso del tiempo y de la muerte, los personajes de Camus y Landero experimentan el absurdo, del que intentan liberarse mediante la rebeldía, la libertad y la pasión, aspectos que comparten ambos escritores, así como la aceptación de los límites y la unidad panteísta con la naturaleza, que suscita la estética de una sensibilidad desgarradora. Coinciden asimismo en el modo de expresar el absurdo mediante técnicas genuinamente kafkianas, como el extrañamiento, que implica convertir lo cotidiano en insólito, la intersección –tan cervantina– de realidad y ficción, las isotopías léxicas y semánticas sobre el absurdo y el azar, y el despliegue de la retórica de la incertidumbre, o de la oscilación, que, a través de la paradoja, el perspectivismo y la ambigüedad, intensifican el absurdo. Pero también existen divergencias entre ambos, ya que Landero reactualiza la filosofía y expresión de Camus con matices lúdicos y paródicos posmodernos que ceden a la palabra la función de catalizador para la absolución de dicho absurdo.

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34

Feng, Lun, William G. Fahrenholtz, and Donald W. Brenner. "High-Entropy Ultra-High-Temperature Borides and Carbides: A New Class of Materials for Extreme Environments." Annual Review of Materials Research 51, no. 1 (July 26, 2021): 165–85. http://dx.doi.org/10.1146/annurev-matsci-080819-121217.

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Herein, we critically evaluate computational and experimental studies in the emerging field of high-entropy ultra-high-temperature ceramics. High-entropy ultra-high-temperature ceramics are candidates for use in extreme environments that include temperatures over 2,000°C, heat fluxes of hundreds of watts per square centimeter, or irradiation from neutrons with energies of several megaelectron volts. Computational studies have been used to predict the ability to synthesize stable high-entropy materials as well as the resulting properties but face challenges such as the number and complexity of unique bonding environments that are possible for these compositionally complex compounds. Experimental studies have synthesized and densified a large number of different high-entropy borides and carbides, but no systematic studies of composition-structure-property relationships have been completed. Overall, this emerging field presents a number of exciting research challenges and numerous opportunities for future studies.

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35

Silva, Lucas Pedrosa da, Natália Camargo Nascimento, and Emerson Mario Boldo. "Aplicação da metodologia Design of Experiment (DoE) para otimizar o processo de compressão de comprimidos mastigáveis numa indústria farmacêutica." Research, Society and Development 9, no. 11 (December 2, 2020): e72991110428. http://dx.doi.org/10.33448/rsd-v9i11.10428.

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A etapa de compressão de comprimidos na indústria farmacêutica é um processo complexo, com inúmeras variáveis e parâmetros de resposta. Durante o ciclo de vida de um medicamento, o produto pode sofrer alterações que podem afetar na formação dos comprimidos em função da necessidade de ganho de performance na compressora, troca de fornecedores de insumos ou aumento de lote, por exemplo. O presente trabalho tem como objetivo a otimização do processo de compressão de um produto de linha visando o aumento de velocidade (comprimidos/hora). O trabalho foi conduzido utilizando a metodologia Design of Experiments (DoE) a fim de identificar e correlacionar os parâmetros críticos durante o processo que afetam na manutenção da velocidade de compressão. Para tanto, foi aplicado a metodologia DoE preconizada no Quality by Design (QbD) e descrita no guia ICQ8, para avaliarmos as interações dos parâmetros entre si e apontar as condições ótimas para a compressão do produto. Utilizamos para suportar os experimentos os testes de Tempo de Desintegração, Dureza Média e Variação de Dureza, Peso Médio e Friabilidade. Como resultado, obtivemos que os atributos de qualidade de desintegração e friabilidade não geraram um modelo significativo. Porém conseguimos estabelecer correlações entre velocidade do Fill-O-Matic (FOM) e força de compressão principal nas respostas de variação de peso, dureza e dureza média.

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Bertram, C. D., N. Truong, and S. D. Hall. "IW3 Design of PIV Experiments on Collapsible-Tube Oscillation Onset, to Match Numerical Simulations(International Workshop on Biomechanics and Tissue Engineering at Micro-and Nanoscale Levels)." Proceedings of the Bioengineering Conference Annual Meeting of BED/JSME 2006.19 (2007): 5–6. http://dx.doi.org/10.1299/jsmebio.2006.19.5.

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Wang, Hanzhang, and Yisha Liu. "A low-cost autonomous navigation system for a quadrotor in complex outdoor environments." International Journal of Advanced Robotic Systems 17, no. 1 (January 1, 2020): 172988142090515. http://dx.doi.org/10.1177/1729881420905150.

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In this article, we design a low-cost navigation system for a quadrotor working in unknown outdoor environments. To reduce the computing burden of the quadrotor, we build a separated system and transfer the computing resources from onboard side to ground station side. Both sides’ communication is guaranteed by 5G wireless networks. We utilize a stereo camera to acquire point clouds and build Octomap for the quadrotor’s navigation. Then, the trajectory is generated in two stages. In the first stage, a modified RRT*-CONNECT algorithm is adopted to generate a set of collision-free waypoints. In the second stage, a curve fitting algorithm is utilized to get a smooth piecewise Bezier trajectory. The advantage of the proposed method is to optimize the path into a safe, smooth, and dynamically feasible trajectory in real time. The modules of the state estimation, dense mapping, and motion planning are integrated into a DJI Matrice 100 quadrotor. Finally, simulation and experiments are both conducted to show the validity and practicality of our method.

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Dong, X., T. He, Y. Huo, and A. Sun. "Experimental preparation of short-carbon-fiber-reinforced Al-5Cu matrix composites using vacuum suction casting." Materiali in tehnologije 54, no. 5 (October 16, 2020): 613–19. http://dx.doi.org/10.17222/mit.2019.217.

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Arroyo, Jorge, Yuan Almora, Mariano Quino, Ernesto Raez, Jaime Martínez, Jesús Buendía, Deybis Baca, and Renan Hañari. "Efecto protector en cirrosis hepática inducida en ratas del extracto etanólico de las hojas de Piper aduncum comparado con silimarina." Anales de la Facultad de Medicina 73, no. 2 (November 22, 2012): 85. http://dx.doi.org/10.15381/anales.v73i2.817.

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Objetivos: Evaluar la eficacia protectora del extracto etanólico de hojas de Piper aduncum (matico) y su fitomedicamento en cápsulas, en la cirrosis hepática inducida en ratas. Diseño: Experimental. Lugar: Facultad Medicina, Universidad Nacional Mayor de San Marcos, Lima, Perú. Material biológico: Hojas de Piper aduncum, y Rattus norvegicus, cepa Holtzman. Intervenciones: Las hojas fueron recolectadas en el distrito de Huariaca, departamento de Pasco. El fitomedicamento en cápsulas se preparó a partir del extracto etanólico de la planta. La cirrosis fue inducida con fenobarbital 0,5 mg/mL, diluida en el agua de beber por 15 días, y luego, tetracloruro de carbono 0,2mL/kg en aceite de oliva 1:1, oralmente por 7 días. Se colectó una muestra de sangre para determinar perfil hepático y malondialdehído; los animales fueron sacrificados extrayéndose el hígado para estudio histopatológico. Los datos fueron evaluados mediante técnicas multivariadas, con valor p < 0,05. Principales medidas de resultados: Grado de lesión hepática, marcadores bioquímicos, estrés oxidativo. Resultados: El extracto y el fitomedicamento a 200 mg/kg disminuyeron los valores de TGP (p < 0,621), bilirrubina total (p < 0,385) y bilirrubina directa (p < 0,283) e incrementaron las proteínas totales (p < 0,539) y albúmina (p < 0,114), similar al grupo silimarina. El colágeno, la fibrosis y el nivel de daño hepático se vieron aumentados con tetracloruro de carbono; estos indicadores se redujeron con los diferentes tratamientos y la silimarina. El marcador de estrés oxidativo se redujo con los tratamientos aplicados (p < 0,002). Conclusiones: El extracto etanólico de las hojas de Piper aduncum (matico) y su fitomedicamento ejercieron efecto protector de la cirrosis inducida en ratas, comparativamente con la silimarina.

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Yang, Juntang, Yogesh Khedar, Mohamed Khalil Ben-Larbi, Jan Backhaus, Astrid Lampert, Ulf Bestmann, and Enrico Stoll. "Concept and Feasibility Evaluation of Distributed Sensor-Based Measurement Systems Using Formation Flying Multicopters." Atmosphere 12, no. 7 (July 6, 2021): 874. http://dx.doi.org/10.3390/atmos12070874.

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Unmanned aerial vehicles (UAVs) have been used for increasing research applications in atmospheric measurements. However, most current solutions for these applications are based on a single UAV with limited payload capacity. In order to address the limitations of the single UAV-based approach, this paper proposes a new concept of measurements using tandem flying multicopters as a distributed sensor platform. Key challenges of the proposed concept are identified including the relative position estimation and control in wind-perturbed outdoor environment and the precise alignment of payloads. In the proposed concept, sliding mode control is chosen as the relative position controller and a gimbal stabilization system is introduced to achieve fine payload alignment. The characterization of the position estimation sensors (including global navigation satellite system and real-time kinematics) and flight controller is carried out using different UAVs (a DJI Matrice M600 Pro Hexacopter and Tarot X4 frame based Quadcopter) under different wind levels. Based on the experimental data, the performance of the sliding mode controller and the performance of the gimbal stabilization system are evaluated in a hardware-in-the-loop simulation environment (called ELISSA). Preliminary achievable control accuracies of the relative position and attitude of subsystems in the proposed concept are estimated based on experimental results.

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Enciso, Edwin, and Jorge Arroyo. "Efecto antiinflamatorio y antioxidante de los flavonoides de las hojas de Jungia rugosa Less (matico de puna) en un modelo experimental en ratas." Anales de la Facultad de Medicina 72, no. 4 (February 20, 2013): 231. http://dx.doi.org/10.15381/anales.v72i4.1074.

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Objetivos: Evaluar la actividad antiinflamatoria y antioxidante de la fracción flavónica extraída de las hojas de Jungia rugosa Less. Diseño: Experimental. Lugar: Facultades de Medicina y Farmacia y Bioquímica, Universidad Nacional Mayor de San Marcos, Lima, Perú. Material biológico: Fracción flavónica extraído de las hojas de Jungia rugosa Less y ratas. Intervenciones: Las hojas de Jungia rugosa Less fueron recolectadas en el cerro Condorcunca, a 3 500 msnm, distrito de Quinua, departamento de Ayacucho. La actividad antiinflamatoria fue evaluada in vivo usando el método de edema plantar inducido por carragenina y en sangre se cuantificó los niveles séricos de interleuquinas 1, 6 y proteína C reactiva (PCR); también, se indujo el granuloma, según Sedwicks, evaluándose por histopatología. La actividad antioxidante fue evaluada in vitro mediante la neutralización del radical 1,1-difenil-2-picril-hidrazilo (DPPH). Principales medidas de resultados: Actividad antiinflamatoria y antioxidante. Resultados: La inflamación disminuyó en 43,8%, y los niveles de interleuquinas 1, 6 y PCR lo fueron en 80%, 90% y 78%, respectivamente, al ser comparados con el control (p<0,05), siendo el efecto dosis dependiente, y brindó un 97,7% de inhibición de radicales DPPH. Conclusión: Se ha demostrado que la fracción flavónica extraída de las hojas de Jungia rugosa Less es antiinflamatoria y antioxidante.

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Ferreira, Helena M., Elsa B. Lopes, José F. Malta, Luís M. Ferreira, Maria H. Casimiro, Luís Santos, Manuel F. C. Pereira, and Antonio Pereira Gonçalves. "Preparation, thermal stability and electrical transport properties of vaesite, NiS2." PeerJ Materials Science 1 (November 15, 2019): e2. http://dx.doi.org/10.7717/peerj-matsci.2.

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Vaesite, a nickel chalcogenide with NiS2 formula, has been synthetized and studied by theoretical and experimental methods. NiS2 was prepared by solid-state reaction under vacuum and densified by hot-pressing, at different consolidation conditions. Dense single-phase pellets (relative densities >94%) were obtained, without significant lattice distortions for different hot-pressing conditions. The thermal stability of NiS2 was studied by thermogravimetric analysis. Both as-synthetized and hot-pressed NiS2 have a single phase nature, although some hot-pressed samples had traces of the sulfur deficient phase, Ni1-xS (<1%vol), due to the strong desulfurization at T > 340 °C. The electronic band structure and density of states were calculated by Density Functional Theory (DFT), indicating a metallic behavior. However, the electronic transport measurements showed p-type semiconductivity for bulk NiS2, verifying its characteristic behavior has a Mott insulator. The consolidation conditions strongly influence the electronic properties, with the best room-temperature Seebeck coefficient, electrical resistivity and power factor being 182 µVK−1, 2,257 µΩ m and 14.1 µWK−2 m−1, respectively, pointing this compound as a good starting point for a new family of thermoelectric materials.

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Baker, Camille. "How Big Was the Roman Empire?" Mathematics Teaching in the Middle School 1, no. 9 (March 1996): 754–59. http://dx.doi.org/10.5951/mtms.1.9.0754.

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This activity was designed as part of a sixth-grade interdisciplinary unit. “Seeing the World through the Eyes of Ancient Greeks and Romans.” In addition to learning about Greek and Roman geography, economics, government, and societies in social-studies class. students studied ancient scientists, physicians. and inventors in science class. They also explored Greek and Roman myths, religions, languages, and ideas in language-arts classes. In mathe matics classes, students experimented with the golden ratio and the pentagram. wrote an essay on how the Greeks used mathematics to understand their world, examined Greek and Roman architecture, and investigated the physical size of the Roman Empire. To culminate the unit, students worked in small groups on special projects, such as building a scale model of the Parthenon, measuring and creating a cale drawing comparing the soccer field with the Pantheon, creating and performing original myths or plays depicting life in ancient Greece and Rome, and constructing simple machines or demonstrations of the scientists' work in Greek and Roman times.

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Moreno Espinosa, Pastora Magdalena, Fidel González-Quiñones, and Claudia Rocío Jurado Rodríguez. "El estudiante universitario de periodismo y su perfil como usuario de internet. Análisis comparativo entre España y México." Estudios sobre el Mensaje Periodístico 26, no. 3 (May 13, 2020): 1079–91. http://dx.doi.org/10.5209/esmp.68410.

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La presente investigación tiene como objetivo realizar un análisis comparativo de las autopercepciones sobre las capacidades digitales de estudiantes que cursan de manera presencial la carrera de periodismo en la Universidad de Sevilla, España y la Universidad Autónoma de Chihuahua, México. La metodología es descriptiva y no experimental transeccional, basada en un censo por medio de la aplicación de un instrumento que divide propuestas y consideraciones en cuatro dimenciones: Capacidades en TIC, alfabetización informacional, capacidades en comunicación y capacidad en generación de contenidos. El énfasis principal en el enfoque teórico no son exclusivamente los estudiantes, o “nativos digitales”, sino los profesores de la misma área, pues se hace especial énfasis en la necesidad de alfabetización digital que debe tener el docente para lograr una comunicación satisfactoria entre nativo y no nativo digital. Los resultados proporcionan un escenario heterogéneo y pleno de matices, pero, a su vez, revelan hallazgos significativos y similitudes en las preferencias, tiempos de conexión y tecnologías utilizadas por ambos grupos de estudiantes, a pesar del abismo encontrado en el ingreso económico familiar entre los estudiantes de México y España.

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Saal, James E., Anton O. Oliynyk, and Bryce Meredig. "Machine Learning in Materials Discovery: Confirmed Predictions and Their Underlying Approaches." Annual Review of Materials Research 50, no. 1 (July 1, 2020): 49–69. http://dx.doi.org/10.1146/annurev-matsci-090319-010954.

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The rapidly growing interest in machine learning (ML) for materials discovery has resulted in a large body of published work. However, only a small fraction of these publications includes confirmation of ML predictions, either via experiment or via physics-based simulations. In this review, we first identify the core components common to materials informatics discovery pipelines, such as training data, choice of ML algorithm, and measurement of model performance. Then we discuss some prominent examples of validated ML-driven materials discovery across a wide variety of materials classes, with special attention to methodological considerations and advances. Across these case studies, we identify several common themes, such as the use of domain knowledge to inform ML models.

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Sandy, Alec R., Qingteng Zhang, and Laurence B. Lurio. "Hard X-Ray Photon Correlation Spectroscopy Methods for Materials Studies." Annual Review of Materials Research 48, no. 1 (July 2018): 167–90. http://dx.doi.org/10.1146/annurev-matsci-070317-124334.

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Understanding and designing sophisticated new materials require measurements of not only their average structural properties but also their dynamic behavior. X-ray photon correlation spectroscopy (XPCS) provides this information by characterizing fluctuations in condensed matter across a broad range of length scales and timescales. Over the past two decades, XPCS has provided a wide variety of results in the study of materials properties. In this review, we provide an overview of coherence, photon correlation spectroscopy, and the dynamic structure factor as well as information on the mechanics of XPCS experiments. We highlight the impact that this infrastructure has had on materials research and the bright future that is forthcoming with the anticipated upgrade of many third-generation synchrotron sources to fourth-generation multibend achromat sources.

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Bertin, Nicolas, Ryan B. Sills, and Wei Cai. "Frontiers in the Simulation of Dislocations." Annual Review of Materials Research 50, no. 1 (July 1, 2020): 437–64. http://dx.doi.org/10.1146/annurev-matsci-091819-015500.

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Dislocations play a vital role in the mechanical behavior of crystalline materials during deformation. To capture dislocation phenomena across all relevant scales, a multiscale modeling framework of plasticity has emerged, with the goal of reaching a quantitative understanding of microstructure–property relations, for instance, to predict the strength and toughness of metals and alloys for engineering applications. This review describes the state of the art of the major dislocation modeling techniques, and then discusses how recent progress can be leveraged to advance the frontiers in simulations of dislocations. The frontiers of dislocation modeling include opportunities to establish quantitative connections between the scales, validate models against experiments, and use data science methods (e.g., machine learning) to gain an understanding of and enhance the current predictive capabilities.

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Hamilton, Brenden W., Michael N. Sakano, Chunyu Li, and Alejandro Strachan. "Chemistry Under Shock Conditions." Annual Review of Materials Research 51, no. 1 (July 26, 2021): 101–30. http://dx.doi.org/10.1146/annurev-matsci-080819-120123.

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Shock loading takes materials from ambient conditions to extreme conditions of temperature and nonhydrostatic stress on picosecond timescales. In molecular materials the fast loading results in temporary nonequilibrium conditions with overheated low-frequency modes and relatively cold, high-frequency, intramolecular modes; coupling the shock front with the material's microstructure and defects results in energy localization in hot spots. These processes can conspire to lead to a material response not observed under quasi-static loads. This review focuses on chemical reactions induced by dynamical loading, the understanding of which requires bringing together materials science, shock physics, and condensed matter chemistry. Recent progress in experiments and simulations holds the key to the answer of long-standing grand challenges with implications for the initiation of detonation and life on Earth.

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Gómez Herrera, Claudia Marcela. "¿Existencia auténtica en la época de la técnica?" Estudios de Filosofía, no. 61 (February 4, 2020): 167–85. http://dx.doi.org/10.17533/udea.ef.n61a11.

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En sus escritos tempranos Heidegger plantea que la existencia fluctúa entre un modo de ser auténtico e inauténtico. Una de las diferencias que se establece entre estos modos de la existencia consiste en la manera en la que se experimenta el tiempo en uno y otro. El presente artículo pretende proponer un enlace entre las nociones de temporalidad heideggeriana y, a la luz de dicho enlace, establecer los rasgos que la existencia auténtica podría adquirir en la época de la técnica. Para lograr este propósito, retomaré una cita de Borges con el fin de esbozar cómo podría pensarse una relación entre las dos nociones de temporalidad. Una vez esbozada la relación, se revisarán algunas de las tesis heideggerianas sobre la época de la técnica que nos ofrezcan las herramientas para reflexionar acerca de los matices que adopta la existencia auténtica en nuestra época. En ese sentido, sugiero que la serenidad puede concebirse como la manera en la que la existencia auténtica actúa. La serenidad no es pasividad del hombre frente a la técnica, sino un modo de responder al acontecer del ser, una manera genuina de actuar acorde a la época.

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Demichelis, Raffaella, Alicia Schuitemaker, Natalya A. Garcia, Katarzyna B. Koziara, Marco De La Pierre, Paolo Raiteri, and Julian D. Gale. "Simulation of Crystallization of Biominerals." Annual Review of Materials Research 48, no. 1 (July 2018): 327–52. http://dx.doi.org/10.1146/annurev-matsci-070317-124327.

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Biominerals are crucial materials that play a vital role in many forms of life. Understanding the various steps through which ions in aqueous environment associate to form increasingly structured particles that eventually transform into the final crystalline or amorphous poly(a)morph in the presence of biologically active molecules is therefore of great significance. In this context, computer modeling is now able to provide an accurate atomistic picture of the dynamics and thermodynamics of possible association events in solution, as well as to make predictions as to particle stability and possible alternative nucleation pathways, as a complement to experiment. This review provides a general overview of the most significant computational methods and of their achievements in this field, with a focus on calcium carbonate as the most abundant biomineral.

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Journal articles on the topic 'Matice experimentů'

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