2469 research outputs found
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Algorithms for routing and spectrum allocation in elastic optical networks: a taxonomy
No full textCorresponding author: César F. Bogado-Martínez; ([email protected]).Elastic Optical Networks (EONs) increase the transport capacity of standard optical networks, and have been proposed as a short-term solution to satisfy the dynamic demands of service quality requirements. To this end, the development of algorithms to better facilitate Routing and Spectrum Allocation (RSA) is envisaged to have a critical impact on the performance of EON. Given the abundance of RSA algorithms, this study presents the unique challenge of organizing and classifying them meaningfully to understand and select the most suitable approach for the corresponding niche service quality requirements. This study proposes a novel taxonomy structure for grouping RSA algorithms based on the following criteria: (1) resource assignment policies, (2) flexibility type, (3) traffic type, (4) optimization approaches, (5) number of objective functions, and (6) problem separability. Finally, the contributions of this study are twofold: it presents a state-of-the-art taxonomy framework that organizes existing published works based on a set of predetermined criteria, and explores research opportunities involving RSA algorithms to realize the full potential of EONs in telecommunications.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 excelenci
Estructura espacial policéntrica del Área Metropolitana de Asunción (AMA)
No full textEl policentrismo en el área metropolitana es un fenómeno relativamente nuevo, que comprende la coexistencia de varios centros de empleo o subcentros. Esta línea de estudio se basa en variables de localización y densidad de empleo para la determinación de la estructura espacial de los territorios.
El hallazgo principal corresponde a la identificación de dos subcentros de empleo: Fernando de la Mora y San Lorenzo. El modelo de estructura espacial del empleo en el AMA confirma que esta tiende al policentrismo, con mayor densidad de empleo en zonas cercanas a los subcentros.
Por la relevancia económica, social y ambiental que tiene el vínculo entre el lugar donde trabajan las personas y el lugar donde residen, se requiere un mayor énfasis de las políticas públicas en la planificación del territorio. Las recomendaciones de este estudio giran en torno a la coordinación vertical y horizontal, la planificación del transporte urbano en un escenario policéntrico (reconociendo a Asunción y los subcentros de empleo como destinos clave en el día a día), el aprovechamiento de las ventajas del policentrismo en términos de menores costos y la generación de datos de empleo con mayor desagregación espacial.
Finalmente, se logró obtener una descripción global de la estructura espacial del empleo en el AMA. Los resultados, obtenidos con base científica, sirven como soporte teórico para la posterior generación de políticas públicas basadas en evidencias.Consejo Nacional de Ciencia y TecnologíaPrograma Paraguayo para el Desarrollo de la Ciencia y Tecnología. Proyectos de investigación y desarroll
Multi-objective evolutionary algorithms based operation sequence design for image segmentation
Full text linkImage segmentation transforms an image into a more understandable representation by grouping pixels with common characteristics, making it easier to identify regions of interest. There is no optimal segmentation method for all cases, which makes it challenging to select the appropriate technique for each image. We propose using a Multi-Objective Evolutionary Algorithm (MOEA) to generate sequences of operations adapted to specific applications. The evolutionary process was guided by objective functions based on Receiver Operating Characteristics (ROC) Curve analysis, using maximization of sensitivity and specificity. The experiments were performed with three types of images: cells (type A, B, C, and D), melanoma images (benign and malignant), and retinal ophthalmoscopic images. The results show that the algorithm achieves a sensitivity (TPR) and specificity (TNR) of up to 1.0 in the segmentation of images of type A and D cells, a sensitivity of 1.0 and specificity of 0.9765 in the segmentation of images of benign melanoma, a sensitivity of 0.9857 and specificity of 0.9825 in the segmentation of malignant melanoma images, and sensitivity of 0.8931 and specificity of 0.9104 in the extraction of retinal veins in ophthalmoscopic images.Consejo Nacional de Ciencia y TecnologíaPrograma Paraguayo para el Desarrollo de la Ciencia y Tecnología. Proyectos de investigación y desarroll
Production of American lettuce cultivars under different colored shade nets
Full text linkEmail: Cipriano Ramón Enciso Garay, [email protected] (autor de correspondencia)Shading nets are used to reduce the amount of radiant energy reaching crops. The objective of the work was to compare the influence of black and red shading nets on the production of nine American lettuce cultivars in the Autumn period under the conditions of the Central Department of Paraguay. The experiment was carried out in the Experimental Field of the Departmental Agronomic Center (CAD) in the Municipality of Julián Augusto Saldívar. The treatments consisted of the combination of two types of shading netting (red with 35% shade and black with 35% shade) and nine cultivars of American lettuce (Julia, Dora, Angelina, Tainá, Sun Valley, Betty, Lucy Brown, Mara, and Serena) totaling 18 treatments. The experiment consisted in a complete randomized block design, arranged in split blocks 2×9 (the color of shading netting was considered the main plot, and the lettuce cultivars as the secondary plot) with four repetitions. Each experimental unit consisted of four crop rows with seven plants. Plant diameter, plant height, head diameter and height, commercial number of leaves per plant, fresh mass, and commercial productivity were evaluated. The data were subjected to analysis of variance, and when differences were found, the means were compared by the Scott-Knott test at 5% probability. The results indicate that using the red netting with the Serena and Dora cultivars provides greater fresh mass and commercial production.Las mallas de sombra se utilizan para reducir la cantidad de energía radiante que llega a los cultivos. El objetivo de este trabajo fue comparar la influencia de las mallas sombreadoras negras y rojas en la producción de nueve cultivares de lechuga americana en el período otoñal en las condiciones del Departamento Central del Paraguay. El experimento se realizó en el Campo Experimental del Centro Agronómico Departamental (CAD), en el municipio de Julián Augusto Saldívar. Los tratamientos consistieron en una combinación de dos tipos de malla sombra (roja con 35% de sombra y negra con 35% de sombra) y nueve cultivares de lechuga americana (Julia, Dora, Angelina, Tainá, Sun Valley, Betty, Lucy Brown, Mara y Serena) totalizando 18 tratamientos. El diseño experimental fue en franjas en bloques completos al azar de 2×9 (las mallas de color fueron consideradas la parcela principal y los cultivares la parcela secundaria) y cuatro repeticiones. Cada unidad experimental constó de cuatro hileras de cultivo, con siete plantas. Se evaluó diámetro de planta, altura de planta, diámetro y altura de cabeza, número comercializable de hojas por planta, masa fresca y rendimiento comercializable. Los resultados fueron sometidos a análisis de varianza y, cuando se encontraron diferencias significativas, se usó la prueba de Scott-Knott al 5% de probabilidad para la comparación de medias. Los resultados indican que el uso de la red roja con los cultivares Serena y Dora proporciona mayor producción de masa fresca y comercializable.Consejo Nacional de Ciencia y TecnologíaPrograma Paraguayo para el Desarrollo de la Ciencia y Tecnología. Proyectos de investigación y desarroll
Excess tuberculosis risk during and following incarceration in Paraguay : a retrospective cohort study
Full text linkCorresponding author. Cátedra de Salud Pública, Universidad Nacional de Asunción (UNA), Paraguay. E-mail address: [email protected] (G. Sequera).Background. The increased risk of tuberculosis (TB) among people deprived of liberty (PDL) is due to individual and institution-level factors. We followed a cohort of PDL from 5 prisons in Paraguay to describe the risk of TB during incarceration and after they were released.
Methods. We linked a 2013 national census of prisons with TB records from the TB Program from 2010 to 2021 to identify TB notifications among incarcerated and formerly incarcerated individuals. We used multivariable Cox regression models to quantify the risk of TB during and following incarceration and to identify risk factors associated with TB.
Findings. Among 2996 individuals incarcerated, 451 (15.1%) were diagnosed with TB. Of these, 262 (58.1%) cases occurred during incarceration and 189 (41.9%) occurred in the community after release. In prison, the hazard ratio of developing TB was 1.97 (95% CI: 1.52–2.61) after six months of incarceration and increased to 2.78 (95% CI: 1.82–4.24) after 36 months compared with the first six months. The overall TB notification rate was 2940 per 100,000 person-years. This rate increased with the duration of incarceration from 1335 per 100,000 person-years in the first year to 8455 per 100,000 person-years after 8 years. Among former prisoners, the rate of TB decreased from 1717 in
the first year after release to 593 per 100 000 person-years after 8 years of follow up.
Interpretation. Our study shows the alarming risk of TB associated with prison environments in Paraguay, and how this risk persists for years following incarceration. Effective TB control measures to protect the health of people during and following incarceration are urgently needed.Consejo Nacional de Ciencia y TecnologíaPrograma Paraguayo para el Desarrollo de la Ciencia y Tecnología. Proyectos de investigación y desarroll
Mapa de Talentos : un procedimiento piloto de detección universal del talento en estudiantes del Paraguay
No full textEste proyecto piloto tuvo como objetivo la detección de talentos intelectuales en estudiantes de Educación Escolar Básica y Educación Media de instituciones educativas del sector público, privado y subvencionado, buscando determinar procedimientos que puedan ser escalables a todo el país. Para ello, se realizó un estudio descriptivo-exploratorio. La muestra fue no probabilística y dirigida según criterios relevantes a la investigación, y estuvo conformada por 1.220 estudiantes de cinco ciudades del departamento Central y de la capital, Asunción, del Paraguay. Los participantes fueron evaluados con instrumentos que miden razonamiento abstracto: el Test de Matrices Progresivas Escala Avanzada de Raven, Matrices Test Adaptativo Informatizado (Matrices TAI) y Test de Inteligencia Breve de Reynolds, teniendo mayor facilidad de aplicación la Escala Avanzada de Raven. Además de su facilidad, esta escala es no verbal y tiene menor sesgo cultural, reduciendo posibles barreras lingüísticas y culturales para una evaluación más justa y precisa. Usando puntos de corte desde el percentil 90, se detectaron 68 estudiantes con potencial de altas capacidades que representan al 5,6% de la muestra. Este hallazgo apoya el uso de normas locales para detectar a estudiantes en el extremo superior de la distribución al realizar detección universal del talento.This pilot project aimed to detect intellectual ability in students from 7th to 12th grade in public, private and subsidized schools, to determine procedures that could be scalable throughout the country in a descriptive-exploratory study. The sample was non-probabilistic and purposeful according to criteria relevant to the study; it included 1220 students from five cities of the Central Department and the Capital, Asuncion, in Paraguay. Participants completed tests that measure abstract reasoning: the Raven Advanced Progressive Matrices Test, the Computerized Adaptive Matrices Test and the Reynolds Intelligence Screening Test, with the Raven Advanced Scale being easiest to implement. Besides its ease of utilization, this test is non-verbal and with less cultural bias, reducing possible linguistic and cultural barriers for fair and precise assessment. Using cut-off points in the 90th percentile, 68 students with High Ability were detected, representing 5.6% of the sample. This finding supports the use of local norms to detect students at the upper end of the distribution when conducting universal screening for giftedness and talent.Consejo Nacional de Ciencia y TecnologíaAcuerdo Específico 02/2021 Mapa de Talentos 1.
Proteomic analysis and lethality of the venom of Aegaeobuthus nigrocinctus, a scorpion of medical significance in the Middle East
No full textCorresponding author at: Adolfo Borges, Centro para el Desarrollo de la Investigación Científica, Manduvirá 635, Asunción 1255, Paraguay.
[email protected] scorpion Aegaeobuthus nigrocinctus inhabits areas in Turkey and the Levant region of the Middle East where severe/lethal envenomings have been reported. Previous research indicated its extreme venom lethality to vertebrates and distinct envenomation syndrome. We report on the composition of A. nigrocinctus venom from Lebanese specimens using nESI-MS/MS, MALDI-TOF MS, SDS-PAGE and RP-HPLC. Venom lethality in mice was also assessed (LD50 = 1.05 (0.19–1.91) mg/kg, i.p), confirming A. nigrocinctus venom toxicity from Levantine populations. Forty-seven peaks were resolved using RP-HPLC, 25 of which eluted between 20 and 40 % acetonitrile. In reducing SDS-PAGE, most predominant components were <10 kDa, with minor components at higher molecular masses of 19.6, 26.1, 46.3 and 57.7 kDa. MALDI-TOF venom fingerprinting detected 20 components within the 1,000–12,000 m/z range. Whole venom ‘shotgun’ bottom-up nLC-MS/MS approach, combined with in-gel tryptic digestion of SDS-PAGE bands, identified at least 67 different components belonging to 15 venom families, with ion channel-active components (K+ toxins (23); Na+ toxins (20); Cl− toxins (2)) being predominant. The sequence of a peptide (named α-KTx9.13) ortholog to Leiurus hebraeus putative α-KTx9.3 toxin was fully determined, which exhibited 81–96 % identity to other members of the α-KTx9 subfamily targeting Kv1.x and Ca2+-activated K+ channels. Chlorotoxin-like peptides were also identified. Our study underscores the medical significance of A. nigrocinctus in the region and reveals the potential value of its venom components as lead templates for biomedical applications. Future work should address whether available antivenoms in the Middle East are effective against A. nigrocinctus envenoming in the Levant area.Consejo Nacional de Ciencia y TecnologíaPrograma Paraguayo para el Desarrollo de la Ciencia y Tecnología. Programa de repatriación y radicación de investigadores del exteriorPrograma Paraguayo para el Desarrollo de la Ciencia y Tecnología. Fortalecimiento de infraestructura y equipamiento para la investigaciónPrograma Paraguayo para el Desarrollo de la Ciencia y Tecnología. Programa Nacional de Incentivo a los Investigadore
Status and distribution of Paraguayan Procyonidae and Mephitidae (Mammalia: Carnivora)
No full textCorresponding author: [email protected] species of procyonid (Nasua nasua and Procyon cancrivorus) and one species of mephitid (Conepatus chinga) have long been documented to occur in Paraguay, but very little has been published about their ecology in the country since the early 19th Cen¬tury works of Azara and Rengger. Data on the distribution and status of these species in the country is collated from museum specimens, publi¬shed literature and reliable observations to provide a basis for future research. A hierarchical approach is taken towards types of record and maps are provided that distinguish these for all species. All three spe¬cies remain common in the Chaco region west of the Paraguay River, and all are considered of Least Concern. However, this region is expe¬riencing high levels of deforestation and data to assess the potential declines of the species is unavailable. The two species of procyonid are also widespread in the Oriental region, but the status of Conepatus chinga there is unclear. There are multiple reports from the Atlantic Forest region but documentation is limited to fecal molecular samples. Clarifying the distribution of that species in the Oriental region is a priority for research.Due specie di procionidi (Nasua nasua e Procyon cancrivorus) e una specie di mefitidi (Conepatus chinga) sono documentate da tempo in Paraguay, ma molto poco è stato pubblicato sulla loro ecologia nel paese dai tempi del lavoro di Azara e Rengger dell’inizio del XIX secolo. Per fornire una base per future ricerche, sono stati raccolti dati sulla distribuzione e sullo stato di queste specie nel paese da esem¬plari museali, letteratura pubblicata e osservazioni affidabili. Per tutte le specie viene adottato un approccio gerarchico in base al tipo di record includendo le mappe che li caratterizzano. Le tre specie sono comuni a ovest del fiume Paraguay nella regione occidentale del Chaco e sono considerate di Minima Preoccupazione. Tuttavia, la regione sta speri¬mentando alti livelli di deforestazione e non sono disponibili informa¬zioni per determinare il potenziale declino di alcune di queste specie. Le due specie di procionidi sono ampiamente distribuite anche nella regione orientale, ma lo status di Conepatus chinga è incerto. Esistono numerosi rapporti dall’ecoregione della Foresta Atlantica, ma la docu¬mentazione è limitata alle prove molecolari provenienti da campioni fecali. Chiarire la distribuzione di quella specie nella regione orientale è una priorità per la ricerca.Programa Paraguayo para el Desarrollo de la Ciencia y Tecnología. Programa Nacional de Incentivo a los Investigadore
HIF
No full textFotografía ganadora del Primer Puesto del IV Concurso Nacional de Fotografía Científica del CONACYT, en la Categoría Profesional de la temática “Ciencia en acción”. El concurso es una iniciativa del CONACYT, a través del Programa PROCIENCIA II con apoyo del Fondo para la Excelencia de la Educación y la Investigación (FEEI).Consejo Nacional de Ciencia y TecnologíaPrograma Paraguayo para el Desarrollo de la Ciencia y Tecnología. Concursos de divulgación de ciencia y periodismo científic
Desarrollo de productos naturales de cosmética y domisanitarios innovadores en el mercado nacional con potencial de exportación
No full textEl proyecto de Wembé se enfocó en la aplicación de tecnologías avanzadas e investigación para desarrollar productos cosméticos y domisanitarios innovadores. Las investigaciones abarcaron estudios exhaustivos sobre la selección de ingredientes naturales, pruebas de eficacia y seguridad, y el desarrollo de formulaciones efectivas y sostenibles. Se implementaron rigurosos procedimientos de control de calidad y trazabilidad para asegurar la pureza y efectividad de los productos.
El equipo llevó a cabo una investigación detallada sobre ingredientes activos y secundarios, optimizando sus propiedades mediante la formulación de productos como kit capilar y hojas de detergente ecológicas. Los procesos de producción fueron diseñados cuidadosamente, integrando métodos artesanales y tecnologías de control para garantizar productos de alta calidad. Estos avances permitieron a Wembé al próximo lanzamiento de una línea innovadora de productos naturales, que destacan por su enfoque en la investigación, sostenibilidad y potencial de exportación.Consejo Nacional de Ciencia y TecnologíaPrograma de Innovación en Empresas Paraguayas. Proyectos Individuales de Innovación y Desarrollo Tecnológic