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Optimized passive design space exploration of silicon microring resonators
No full textThe authors would like to acknowledge funding support from CONCYTEC-FONDECYT within the call E041-01 [contract number 015-2018-FONDECYT/BM].In this work, we analyze passive parameters for a band of 1500 to 1600 nm in microring resonators (MRRs). Such analysis can be vital for estimating an appropriate parameter design exploration with potential applications on Wavelength Division Multiplexing (WDM) solutions. Using a coupled mode theory-based method, we found optimal design spaces for MRRs with radii from 5 to 10 µm and bus-ring gap from 0.12 to 0.21 µm. For All-Pass MRRs, we found an optimal design space where the transmittances in the resonant frequencies are down to 8% in the Through port, while for the Add-Drop MRRs, we found an optimal design space where for transmittances in the Drop port are from 0.77 to 1. We also found optimal design spaces for Q-factors between 2000 and 3800. To find the optimal ring/radius and bus-ring gap values inside the design spaces, we use the particle swarm optimization technique. The data obtained with the exhibited work also shows a modal analysis for the supermodes formed by the cross-section of the bus-ring interface and the impact of UV-lithography common fabrication errors, even due to wafer die positioning. With the latter, our work provides a comprehensive design space exploration and helps designers to know the effect that typical structural fabrication errors will have on the passive resonance. © 2021 SPIE.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Piezoresponse force microscopy of BaTiO3-chitosan and BaTiO3-polyethylene glycol nanocomposites
No full textThe work was funded by Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica-CONCYTEC according to agreement at Sub project 072–2018–FONDECYT–BM–IADT–AV.Influence of surface modification of barium titanate nanoparticles of spherical shape with the average size of 200 nm in ferroelectric tetragonal crystal phase on the value of piezoelectric response by piezoelectric force microscopy has been studied. It has been found that the modification of the surface of nanoparticles with organic molecules for the increasing of biocompatibility leads to a decrease in the value of effective piezo response from 150 to 48–60 pm/V. At the same time, it is possible to switch polarization in the investigated samples. This allows to consider the mentioned nanocomposites to be promising materials for diagnostics and treatment of cancer tumors, as well as creation of new generation implants accelerating the osteogenesis process. © 2021, The Author(s), under exclusive licence to The Materials Research Society.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Thermodynamic stability of gilded copper and pigments at high relative humidity and at environmental conditions of Lima, Perú
No full textCultural heritage materials are affected by diverse environmental agents such as humidity, temperature, and pollution. This work focuses on studying the thermodynamic stability of Peruvian heritage materials such as gilded coppers and pigments within two scenarios: one under ambient conditions and the other under accelerated conditions established by the ASTM D 2247 standard. In both cases, the HSC Chemistry 6 software was implemented. The general results obtained for gilded coppers showed that by varying the relative humidity from 75% and 14 °C to 80% and 26 °C, the corrosion products move from CuO to Cu(OH) 2. In addition, to Cu2Cl(OH)3-Atacamite-in the presence of chlorin. On the other hand, for hematite (Fe 3O 2), vermilion (HgS), and Minium (Pb 3O 4) pigments, we found that at ambient conditions, with NO 2 and SO 2, they give rise to goethite (FeO(OH)), mercury sulfate (HgSO 4) and lead nitrate (Pb(NO) 3), respectively. These changes also modify the natural colour of pigments, where goethite gives rise to a brownish red, mercury sulfate is colorless and lead nitrate is white. This paper is a quick theoretical way to understand how cultural heritage materials can physically degrade. Future experiment trials will contribute to set strategies towards the correct management of these heritage collections. © Published under licence by IOP Publishing Ltd.The authors acknowledge to Concytec/Banco Mundial for their financial support in the Project "Mejoramiento y Ampliación de los Servicios del Sistema Nacional de Ciencia Tecnología e Innovación Tecnológica, 8682-PE” through its executing unit FONDECYT, contract number 035-2019. This project could not have been possible without the valuable collaboration of María Inés Velarde, Rosanna Kuon, and Lucila Iglesias (Centro de Investigación para la Conservación del Patrimonio, Universidad de Ingeniería y Tecnología (UTEC)), whom we thank for their support in reviewing the text and in the presented figures. Also, Karinna Visurraga, UTEC is thanked for her administrative support
Three new species of Trichoderma in the Harzianum and Longibrachiatum lineages from Peruvian cacao crop soils based on an integrative approach
No full textThis study was supported by National Institute of Agricultural Innovation (INIA) grant 004-2016-INIA-PNIA-UPMSI/IE through the National Program for Agricultural Innovation of Peru (PNIA), by grant 10-2018-FONDECYT-BM-ADT-AV from National Foundation for Scientific, Technological Development and Technological Innovation (Fondecyt) of Peru, and by grant SNIP no. 352641?CEINCACAO.The hyperdiverse genus Trichoderma is one of most useful groups of microbes for a number of human activities, and their accurate identification is crucial. The structural simplicity and lack of distinctive phenotypic variation in this group enable the use of DNA-based species delimitation methods in combination with phylogenies (and morphology when feasible) to establish well-supported boundaries among species. Our study employed a multilocus phylogeny and four DNA-based methods (automated barcode gap discovery [ABGD], statistical parsimony [SPN], generalized mixed Yule coalescent [GMYC], and Bayesian phylogenetics and phylogeography [BPP]) for four molecular markers (acl1, act, rpb2, and tef1) to delimit species of two lineages of Trichoderma. Although incongruence among these methods was observed in our analyses, the genetic distance (ABGD) and coalescence (BPP) methods and the multilocus phylogeny strongly supported and confirmed recognition of 108 and 39 different species in the Harzianum and Longibrachiatum lineages, including three new species associated with cacao farms in northern Peru, namely, T.awajun, sp. nov., T.jaklitschii, sp. nov., and T.peruvianum, sp. nov. Morphological distinctions between the new species and their close relatives are primarily related to growth rates, colony appearance, and size of phialides and conidia. This study confirmed that an integrative approach (DNA-based methods, multilocus phylogeny, and phenotype) is more likely to reliably verify supported species boundaries in Trichoderma. © 2021 The Mycological Society of America.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Twisted tensor products of K 3 with K 3
No full textJorge A. Guccione and Juan J. Guccione were supported by UBACyT 20020150100153BA (UBA) and PIP 11220110100800CO (CONICET). This work was supported by CONCYTEC-FONDECYT within the framework of the contest ?Proyectos de Investigaci?n B?sica 2020-01? [contract number 120-2020-FONDECYT].We describe all the twisted tensor products of K 3 with K 3, where K is an arbitrary field. © 2021 The Author(s). Published with license by Taylor and Francis Group, LLC.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Intereses investigativos y producción científica de mujeres: la pandemia desde las ciencias sociales: un análisis a partir de la base de datos Scopus, 2020-2021
No full textDestaca las contribuciones de las mujeres investigadores de las ciencias sociales en la construcción del conocimiento y pensamiento social en la región, en Iberoamérica y en el mundo, así como su participación en el cambio social. Desde una perspectiva cienciométrica y un enfoque interpretativo analiza 205 artículos científicos en acceso abierto, con el propósito de explorar los intereses de producción científica en acceso abierto de mujeres pertenecientes al área de las ciencias sociales a partir de la base de datos de Scopus e identifica las revistas científicas que publicaron los artículos de autoría femenina desde 2020 hasta febrero de 2021
Evaluación de repositorios de la Red Nacional de Repositorios Digitales de Ciencia, Tecnología e Innovación de Acceso Abierto (RENARE): primeros resultados
No full textPresenta el procedimiento, criterios utilizados, así como los primeros resultados obtenidos en la evaluación de los repositorios institucionales peruanos adheridos a la Red Nacional de Repositorios Digitales de Ciencia, Tecnología e Innovación de Acceso Abierto (RENARE)
Fe content effects on structural, electrical and magnetic properties of Fe-doped ITO polycrystalline powders
No full textFe-doped indium tin oxide (ITO) is an exciting material because it combines the host matrix's good electrical conductivity with the magnetic properties coming from the most earth-abundant transition metal, Fe. In this regard, a single-pot synthesis route based on a polymeric precursor method has been used to produce high-quality undoped and iron-doped ITO with iron content up to 13.0 mol%. The crystal formation in the bixbyite-type structure of all samples is confirmed by X-ray diffraction data analysis. A monotonous decrease of the lattice parameters with the increase of the Fe content is determined, which is consistent with of Fe ions with an oxidation state of 3+ in agreement with the ionic radii difference between In3+ and Fe3+. Raman spectroscopy confirms the bixbyite structure formation and provides evidence of a high surface disorder. 119Sn Mössbauer spectroscopy reveals the formation of only Sn4+ ions. Meanwhile, 57Co Mössbauer spectroscopy suggests the presence of Fe3+ ions in a paramagnetic state. DC magnetization characterization of the Fe-doped ITO nanoparticles confirms the compound's paramagnetic character. The sheet resistance (R/?) measurements provide a lower value for the undoped ITO sample (~0.26 ?/sq) than the one of commercial bulk material. It has been determined that the sheet resistance increases with the Fe content, suggesting the decrease of the conduction electrons density as the iron content is increased. © 2021 Elsevier B.V.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
A quasi-exact solution for the analysis of smart multilayered simply supported shallow shell panels
No full textA quasi-three-dimensional solution for the bending analysis of simply supported orthotropic piezoelectric shallow shell panels subjected to thermal, mechanical and electrical potential is introduced. The mechanical governing equations are derived in term of three-dimensional equilibrium relations and the classical Maxwell's equations. The trough-the-thickness temperature is modeled by the Fourier's heat conduction equation. The coupled partial differential equations are solved by Navier closed form solutions. The trough-the-thickness profile for electrical potential, temperature profile and displacements is obtained by using a quasi-exact method so-called the differential quadrature method (DQM). Chebyshev polynomials of the third kind are used as the basis functions and the grid thickness domain discretization for the DQM. The interlaminar conditions for transverse stresses, temperature and electrical potential are imposed. The correct traction conditions for transverse stresses and scalar potential function at the top and the bottom are applied. The results for cylindrical, spherical and rectangular plates are presented. The excellent obtained results are compared with layerwise and three-dimensional solutions reported in the literature. © 2021Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Diabetes care quality according to facility setting: A cross-sectional analysis in six Peruvian regions
No full textObjective: To characterize diabetes care across healthcare facilities in six Peruvian regions. Methods: Cross-sectional study of patients with type 2 diabetes mellitus (T2DM), ranging from primary care facilities to hospital-based facilities, in six Peruvian regions. Data was collected by health staff trained between 2012 and 2016. We studied six diabetes care outcomes and four adequate diabetes care outcomes considering the healthcare facility as the exposure of interest. We estimated prevalence ratios (PR) and their 95% confidence intervals (95% CI) using Poisson regression with robust variance. Results: Data from 8879 patients with T2DM, mean age 59.1 years (SD ± 12.2), 53.6% males, was analyzed. Of these, 8096 (91.2%) were treated at primary care facilities. The proportions of patients who had HbA1c, LDL-c, and creatinine/microalbumin test performed increased with the setting of the healthcare facility. Overall, 39%–56% of patients had an adequate HbA1c control, being higher in hospital-based facilities with specialists in comparison to primary care facilities. Conclusions: We observed that the higher the setting of the facility, the higher the rate of the assessed diabetes care outcomes and adequate diabetes care for four of the six targets (fasting glucose, HbA1c, LDL-c and creatinine or microalbumin) and for three of the four targets (glucose?130 mg/dL, HbA1c ?7%(53 mmol/mol) and LDL-c <100 mg/dL), respectively. Substantial gaps were observed at the primary care facilities, calling for the strengthening of diabetes care. © 2020 Primary Care Diabetes EuropeConsejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte