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Antioxidant activity, antiproliferative activity, antiviral activity, no production inhibition, and chemical composition of essential oils and crude extracts of leaves, flower buds, and stems of Tetradenia riparia
Full text linkCorrespondence: Zilda Cristiani Gazim, [email protected] article belongs to the Special Issue Anticancer Compounds in Medicinal Plants - In Honour of the 20th Anniversary of Pharmaceuticals.The chemical composition of extracts (CEs) and essential oils (EOs) from Tetradenia riparia leaves, flower buds, and stems was analyzed. Antiproliferative activity against tumor cell lines, NO production inhibition, and antioxidant and antiviral activities were assessed. The CEs contained flavonoids, phenolic acids, coumarins, and saturated fatty acids. The EOs included monoterpenes, oxygenated sesquiterpenes, and diterpenes. NO production inhibition ranged from 76 to 247 µg mL−1, and antiproliferative activity exhibited GI50 between 20 and >204 µg mL−1, with low cytotoxicity (SI: 1.08 to 4.75). Reactive oxygen species inhibition ranged from 45 to 82%. Antioxidant activity varied when determined by the 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay (IC50: 0.51 to 8.47 mg mL−1) and ferric reducing antioxidant power (0.35 to 0.81 µM ferrous sulfate per mg). The reduction in β-carotene–linoleic acid co-oxidation varied between 76.13 and 102.25%. The total phenolic content of CEs and EOs was 10.70 to 111.68 µg gallic acid mg−1. Antiviral activity against herpes simplex virus type 1 (HSV-1) showed an EC50 between 9.64 and 24.55 µg mL−1 and an SI between 8.67 and 15.04. Leaf EOs exhibited an EC50 of 9.64 µg mL−1 and an SI of 15.04. Our study unveils the diverse chemical composition and multifaceted pharmacological properties of T. riparia, demonstrating its potential as a valuable source of bioactive compounds for therapeutic applications.Consejo Nacional de Ciencia y TecnologíaPrograma Paraguayo para el Desarrollo de la Ciencia y Tecnología. Proyectos de investigación y desarroll
Aprendizado de máquina para classificação de variáveis multivariadas em raças bovinas criadas em pântanos do Paraguai
Full text linkCorresponding author - E-mail: [email protected] study focuses on the performance of cows for meat production raised in the wetlands of Paraguay, examining five cattle genotypes: Brahman, Brangus, and Nelore, as well as two local breeds at risk of extinction. The main objective is to identify and rank phenotypic variables, including blood, clinical, hair, and health variables, demonstrating causal linkage with the live weight of the cows analyzed. Initially, high correlations were identified between different variables included in this study; then, using advanced Machine learning (ML) techniques and the application of Shapley additive explanations (SHAP), a deeper understanding was provided of the factors strongly associated with adaptability in these environments, and, therefore, the respective zootechnical performance. The association between cattle genotypic components linked with the season of the year proved to be the most influential factor on cattle live weight. Variables such as hair length, hematocrit, phosphatase, phosphorus, creatine phosphokinase, creatinine, protein, cortisol, calcium, and the presence of endoparasites were highlighted, demonstrating their hierarchical importance for animal selection. ML models are effective tools for establishing hierarchies of relevance in complex phenotypic multivariable, which is crucial in breeding programs for different zootechnical species and in special and specific environments like wetlands.Este estudo foca no desempenho de vacas para produção de carne, criadas nos pântanos do Paraguai, examinando cinco genótipos bovinos; Brahman, Brangus, Nelore, bem como duas raças locais em risco de extinção. O principal objetivo é identificar e classificar variáveis fenotípicas que incluem variáveis sanguíneas, clínicas, de pelagem e saúde, demonstrando ligação causal com o peso vivo das vacas analisadas. Inicialmente, foram identificadas correlações elevadas entre diferentes variáveis incluídas neste estudo, e, então, utilizando técnicas avançadas de aprendizado de máquina e a aplicação de explicações aditivas de Shapley (SHAP), foi proporcionado um entendimento mais profundo dos fatores fortemente associados à adaptabilidade nestes ambientes, e, portanto, o respectivo desempenho zootécnico. A associação entre o componente genotípico bovino ligado à estação do ano mostrou ser o fator influente mais predominante sobre o peso vivo bovino. Variáveis como comprimento do pelo, hematócrito, fosfatase, fósforo, creatina phosphokinase, creatinina, proteína, cortisol, cálcio e a presença de endoparasitas foram destacadas, demonstrando sua importância hierárquica para a seleção animal. Os modelos de ML são ferramentas eficazes para estabelecer hierarquias de relevância em multivariáveis fenotípicas complexas, o que é crucial em programas de melhoramento genético em diferentes espécies zootécnicas, bem como em ambientes especiais e específicos, como os pântanos.Consejo Nacional de Ciencia y TecnologíaPrograma Paraguayo para el Desarrollo de la Ciencia y Tecnología. Financiamiento de estancias de investigació
Impact of knowledge of human papillomavirus positivity on cervical cytology performance in Latin America
Full text linkCorresponding author: Arianis Tatiana Ramírez, Early Detection, Prevention & Infections Branch, International Agency for Research on Cancer, 25 avenue Tony
Garnier, 69007 Lyon, France ([email protected]).Background: Cervical cytology is recommended by the World Health Organization as a triage option in human papillomavirus (HPV)- based cervical cancer screening programs. We assessed the performance of cytology to detect CIN3þ without and with knowledge of HPV positivity.
Methods: Women were screened with cytology and HPV across ESTAMPA study centers in Latin America. Screen-positives were referred to colposcopy with biopsy and treatment as needed. Cytology was initially interpreted without knowing HPV results. A subset of cytologies from HPV-positive women were reinterpreted at the same laboratories, with knowledge of HPV status, blinded to previous cytology and histological diagnosis. Performance indicators for cytology to detect CIN3þ without and with knowledge of HPV positivity were estimated.
Findings: A total of 4087 women were included, of which 490 had histologically confirmed CIN3þ (455 CIN3 and 35 cancers). Cytology sensitivity without knowledge of HPV positivity for CIN3þ was 47.2% (95% CI ¼ 42.5 to 51.9), whereas with knowledge of HPV positivity, the sensitivity was higher (58.9%, 95% CI ¼ 54.2 to 63.5; P<.0001). The specificity without knowledge of HPV was 89.4% (95% CI ¼ 88.2 to 90.5), whereas with knowledge of HPV positivity was 78.9% (95% CI ¼ 77.4 to 80.4; P<.0001). Performance estimates varied by study center for cytology without knowing the HPV positivity (range ¼ 32.8%-61.5% for sensitivity; range ¼ 80.7%-98.6% for specificity). Similarly, performance varied with knowledge of HPV positivity (36.1%-93.4% for sensitivity; 39.6%-98.6% for specificity).
Conclusion: The increase in sensitivity of cytology with HPV knowledge was limited and highly variable, reinforcing the need for alternative triage methods to support cervical cancer elimination goals.Consejo Nacional de Ciencia y TecnologíaPrograma Paraguayo para el Desarrollo de la Ciencia y Tecnología. Proyectos de investigación y desarroll
Improving steady state accuracy in field-weakened six-phase induction machines with integrator and modulated predictive control
Full text linkCorrespondence: [email protected] (M.A.); [email protected] (J.D.-G.)This article belongs to the Section Power Electronics.Finite-control-set model predictive control techniques are considered an exciting option for high-performance control multiphase drives due to their fast dynamic response, ability to handle multiple targets and constraints, and adaptability to different power converters or machine models. However, these techniques have some drawbacks, such as poor current reduction (−) and steady-state error (−), especially in the field weakening zone. Although some proposals have addressed these issues by adding modulation stages or designing new cost functions, there is still room for improvement, especially in steady-state error reduction. Therefore, this article proposes to include an integrator attached to a modulated predictive current controller applied to a six-phase induction machine to improve its performance throughout the entire speed range regarding steady-state error mitigation. Experimental tests were carried out to validate the effectiveness of the proposed controller. Tests were carried out evaluating the reduction of the steady-state error (−), the current tracking, the (−) currents reduction and the total harmonic distortion.Consejo Nacional de Ciencia y TecnologíaPrograma Paraguayo para el Desarrollo de la Ciencia y Tecnología. Proyectos de investigación y desarrolloPrograma Paraguayo para el Desarrollo de la Ciencia y Tecnología. Programa Nacional de Incentivo a los Investigadore
Croando bajo la lluvia
No full textEsta obra es parte de la colección de cuatro libros de cuentos creada en el marco del Proyecto de Comunicación y Divulgación de Ciencia y Tecnología “Guardianes de la noche: Una mirada científica a los animales nocturnos y su importancia en los ecosistemas (COMU01-10)” cofinanciado por el Consejo Nacional de Ciencia y Tecnología (CONACYT) con el apoyo del Fondo para la Excelencia de la Educación y la Investigación (FEEI).La ciencia y la literatura se unen para brindarnos una mirada diferente sobre animales nocturnos que, a pesar de su gran importancia en los ecosistemas, suelen ser incomprendidos y, además, despertar temor. Los cuentos, narrados en español y guaraní, relatan las aventuras de animales que habitan en diversos ecosistemas de Paraguay, brindando información sobre sus características, comportamiento y amenazas que enfrentan. Esta obra forma parte de una colección de cuatro libros de cuentos creados en el marco del Proyecto de Comunicación y Divulgación de Ciencia y Tecnología “Guardianes de la noche: Una mirada científica a los animales nocturnos y su importancia en los ecosistemas (COMU01-10)”. Cada libro contiene dos cuentos que se enfocan en un grupo de animales nocturnos: anfibios, reptiles, aves y murciélagos, e incluyen guías didácticas para docentes. ¡Adéntrate en el misterio y la magia de la vida nocturna, y descubre el verdadero valor de estos asombrosos animales a través de una cautivadora lectura!Consejo Nacional de Ciencia y TecnologíaPrograma Paraguayo para el Desarrollo de la Ciencia y Tecnología. Programa de apoyo a proyectos de comunicación de la ciencia y la tecnologí
Aves de los humedales de Ñeembucú
No full textFotos: Fátima Ortiz [[email protected]], Patricia Salinas y Griselda Zárate. Producido por las autoras con la asistencia de Juliana Philipp y Rayane Ribeiro, Field Museum.Publicado en la Sección "Guías de Campo" del Field Museum.La Ecorregión Ñeembucú está ubicada en la región Oriental de Paraguay, con una superficie aproximada de 35.700 km2. Sus características topográficas y la influencia de los ríos Paraguay y Paraná (Acevedo et al., 1990) propician la presencia de grandes extensiones de humedales, las cuales representan uno de los sistemas biológicos más productivos debido a las funciones ecológicas que cumplen (Evaluación de los Ecosistemas del Milenio, 2005).
Esta guía se desarrolló en tres sitios de los distritos de Tacuaras y Villa Franca (Figuras 1 y 2). Las especies de aves observadas en estos tres sitios fueron registradas en bosque, sabana palmar y pastizal con periodos inundables y en sitios antrópicos. Para la nomenclatura fue actualizada según la lista taxonómica (2021) del Comité de Clasificación Sudamericano de la Sociedad Ornitológica Americana (SACC; Del Castillo et al. 2021).Consejo Nacional de Ciencia y TecnologíaPrograma Paraguayo para el Desarrollo de la Ciencia y Tecnología. Proyectos de investigación y desarroll
Oudemansiella cubensis an edible mushroom from the Neotropics with biological and nutritional benefits
No full textCorresponding author. E-mail address: [email protected] (Michelle Campi).In this work, we evaluated the antioxidant, toxicological, mutagenic, antigenotoxic and nutritional properties of Oudemansiella cubensis, which is a mushroom found in neotropical regions worldwide and native to Paraguay. Nutritional content analyses revealed that O. cubensis is a rich source of protein, dietary fiber, and fats. Antimicrobial analyses showed antimicrobial activity against Pseudomonas aeruginosa and Enterococcus faecalis. Additionally, the species resulted to be nontoxic for human consumption with an LD50 value of 37.1 mg.mL1. The ethanolic extract of O. cubensis showcased an important antimutagenic activity at a concentration of 20 mg.mL1, which promotes the prevention of genotoxic damage. Regarding its chemical profile, Gas Chromatography – Mass Spectrometry confirmed the presence of compounds such as l-(+)-ascorbic acid 2,6-dihexadecanoate, octacosanol and cyclo(l-leucyl-l-prolyl), which stood out for antioxidant and antimicrobial properties. This study provided further evidence that Oudemansiella cubensis is a valuable species because of its potential for biotechnological applications.Consejo Nacional de Ciencia y TecnologíaPrograma Paraguayo para el Desarrollo de la Ciencia y Tecnología. Proyectos de investigación y desarroll
Part I - Advancements in power converter technologies : a focus on SiC-MOSFET-based voltage source converters
Full text linkCorrespondence: Raúl Igmar Gregor Recalde, [email protected] article belongs to the Special Issue Renewable Energy Management System and Power Electronic Converters.Artículo científico premiado con una Mención Honorífica por el Premio Nacional de Ciencias de la edición 2024, otorgado por la Honorable Cámara de Senadores del Congreso Nacional de la República del Paraguay.Power converter technologies have become vital in various applications due to their efficient management of electrical energy. With the growing prominence of renewable energy sources such as solar and wind, the high penetration of power electronic converters has been justified. However, ensuring power quality has emerged as a significant challenge for grid-connected power converters. The divergence from the ideal sinusoidal waveform in terms of magnitude and frequency impacts both grid-side currents and voltages. Several studies have proposed solutions to address power quality issues at the load side. The advancement of power converters has been fueled by the development of high-performance microprocessors and the emergence of high-speed switching devices, such as SiC-MOSFETs. This paper focuses on the design of voltage source converters, particularly those based on SiC-MOSFET semiconductor devices. The article presents the design of H-Bridge cells, discusses two-level voltage source converters based on cascade H-Bridge cells in a parallel configuration with experimental fault analysis, addresses the seven-level voltage source converter topology, and explores the design and experimental results of the matrix converter. The findings underscore the importance of considering the entire converter design for improved performance at high switching frequencies. The article concludes by summarizing the main outcomes and implications of this research.Consejo Nacional de Ciencia y TecnologíaPrograma Paraguayo para el Desarrollo de la Ciencia y Tecnología. Proyectos de creación y fortalecimiento de maestrías y doctorados de excelenciaPrograma Paraguayo para el Desarrollo de la Ciencia y Tecnología. Proyectos de investigación y desarroll
A Herglotz-based integrator for nonholonomic mechanical systems
Full text linkCorrespondence: Email: [email protected]; Tel: +595994787424.We propose a numerical scheme for the time-integration of nonholonomic mechanical systems, both conservative and nonconservative. The scheme is obtained by simultaneously discretizing the constraint equations and the Herglotz variational principle. We validate the method using numerical simulations and contrast them against the results of standard methods from the literature.Consejo Nacional de Ciencia y TecnologíaPrograma Paraguayo para el Desarrollo de la Ciencia y Tecnología. Programa Nacional de Incentivo a los Investigadore
What is Rallus rytirhynchos Vieillot, 1819? : the true identity of Azara’s (1805) No. 372 Ypacahá del Pardo
Full text linkThe identity of the bird described from Paraguay by Félix de Azara as No. 372 Ypacahá del Pardo is confirmed as the immature plumage of the Spotted Rail Pardirallus maculatus maculatus (Boddaert, 1783). This description is the basis for the name Rallus rytirhynchos Vieillot, 1819 which is thus a junior subjective synonym and an available name. Rallus rytirhynchos Vieillot, 1819 is the type species of the genus Ortygonax Heine, 1890. Ortygonax Heine, 1890 is a junior subjective synonym of Pardirallus Bonaparte, 1856 and is also available for application.A identidade da ave do Paraguai descrita por Félix de Azara como No. 372 Ypacahá del Pardo é confirmada como a plumagem imatura da saracura-carijó Pardirallus maculatus maculatus (Boddaert, 1783). Esta descrição e a base para o nome Rallus rytirhynchos Vieillot, 1819 que é, portanto, um sinônimo júnior, e disponível para sua aplicação. Rallus rytirhynchos Vieillot, 1819 é a espécie-tipo do gênero Ortygonax Heine, 1890. Ortygonax Heine, 1890 é um sinônimo júnior de Pardirallus Bonaparte, 1856 e também está disponível para aplicação.Consejo Nacional de Ciencia y TecnologíaPrograma Paraguayo para el Desarrollo de la Ciencia y Tecnología. Programa Nacional de Incentivo a los Investigadore