Revistas UPO (Universidad Pablo de Olivade)
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Synthesis and modification of zeolite A from rice husk for use in water treatment.
Get PDFZeolites are microporous crystalline aluminosilicates that have unique properties for adsorption and ion exchange, making them useful in various applications related to water treatment. For certain applications, zeolites can be synthesized or modified (Mintova et al., 2016) in order to improve their eficiency, resistance or reuse capacity among other properties. Likewise, the synthesis of zeolites can be carried out from agroindustrial wastes in a circular economy scheme with the valorization of these byproducts (Yoldi et al., 2019). In this work, zeolite A was synthesized from rice husk ash obtained from the rice industry, due to its high silicon content (~90%) (Tran-Nguyen et al., 2021) and, after modifying its chemical composition through an ion exchange, its efficiency as a photocatalyst for water treatment was evaluated.
First, silicon is extracted from ashes with the use of a NaOH solution to obtain a soluble silicate and the concentration of extracted silicon is determined by means of a colorimetric analysis. Zeolite A is synthesized by a hydrothermal method by adding a solution of sodium aluminate to the previous silicon extract, in the proportion of Si/Al = 1. Finally, the zeolite is subjected to an ion exchange with a solution of 0,1M FeSO4 so that it incorporates iron as a compensation cation for the loads in its structure.
Finally, its efficiency as a photocatalyst in the degradation of imidacloprid in water is evalated, studying the effect of the concentration of said contaminant, as well as the concentrations of H2O2 and zeolite, under UV and visible light in the heterogeneous photo-Fenton type reaction
Revalorization of tidal waste as sustainable flocculants through clean technologies.
Get PDFThe current trend towards seeking renewable resources, as a consequence of the environmental impact triggered by the use of polluting raw materials, has led to an increase in research on cellulose. This natural polymer accounts for around 1.5×1012 tons of the total annual biomass production and is considered a virtually inexhaustible source of raw material for the growing demand for environmentally friendly products [1]. However, the cellulose industry relies heavily on lignocellulosic biomass such as wood, cotton, flax, hemp, etc., materials in which lignin removal poses a major challenge due to the harsh chemical treatment required, resulting in partial cellulose degradation and the production of highly polluting effluents. For this reason, readily accessible biomass with lower lignin content, such as seaweeds and marine phanerogams, represents a sustainable alternative source of cellulose [2]. Among the various industrial applications of this polymer, the production of flocculants has recently gained popularity for wastewater treatment, due to their non-toxicity and biodegradability compared to chemical flocculants derived from materials like petroleum [3].Therefore, this study examined the production capacity of flocculants using cellulose extracted from tidal waste (seaweeds and marine phanerogams) collected on a beach in Nerja (Malaga, Andalusia, Mediterranean Sea) aiming to revalue beach wrack that accumulate on the coasts causing environmental and economic damage, thus contributing to the framework of the circular economy. To achieve this, 28 experiments were designed with different cooking conditions using the "soda-anthraquinone"process for cellulose extraction. Lignin removal was performed with hydrogen peroxide and the morphologicalcharacterization of the product was carried out using the Morfi Lab equipment (Techpap) [4]. The results obtained revealed key properties in our cellulose fibers through statistical parameters, allowing the selection of the most interesting samples for satisfactory flocculation, highlighting the use of tidal waste as a sustainable alternative to traditionally used chemical flocculants
Filtración de E. coli: metodología, implantación, control de calidad y análisis tecno-económico.
Get PDFWith the rise of human population and environmental awareness, water quality its becoming an important issue because public and environmental health protection requires safe drinking water (Rompré et al., 2002). E. coli is a gram-negative, rod-shaped bacteria that belongs to the family Enterobacteriaceae. The presence of E. coli in water represents an indicator of fecal contamination, since its natural habitat is in the intestines of warm-blooded animals. Therefore, E coli is used as a fecal indicator bacterium granting the importance of quantitatively assesing it for efective water control and ensuring the safety of water resources (Qazi et al., 2024).Even though there are many different methods for E. coli detection with new ones being researched nowadays, not every method is certified to be used in a laboratory for quality control.Currently, three type of assays are used for susch purpose, which are based on the employment of culture media (COMPASS cc AGAR and RAPID'E.coli 2+ supplement water testing) or colorimetry and fluorimetry (Colilert-18/Quanti-Tray) (NF Validation, 2024).For culture media, membrane filter technique is widely approved as a procedure for monitoring drinking water microbial quality. This method consists of filtering a water sample in a sterile filter with 0,45μm pore size which is then incubated in a culture media to count the colonies on the filter.In order to be accredited, a laboratory for water quality must follow a proccess called validation where an external organization confirms if they method is being done effectively or not with a quality control experiment. This experiment consists on inoculating a known quantity of bacteria to check if they can detect a similar number after the method. After being accredited, this research must be conducted with a frequency decided by the laboratory to test whether they are correctly applying the method.On the other hand, even if membrane filtration technique is a viable way of detecting E. coli, it has disadvantages like its inability to recover stressed or injured coliforms. Therefore, new techniques are being researched and will probably be implemented in the near future. This makes a techno-economical analysis important to determine the practical implanatation of some of this new methods
Functional analysis of genes and cis-regulatory elements involved in the specification of optic cup territories identified by scRNAseq and scATACseq.
Get PDFABSTRACTMotivation: In all metazoans, sight depends on the intimate relation and combined function between photoreceptors and pigmented cells, which derive from common precursors through the bifurcation of a single gene regulatory network (GRNs) into two mutually exclusive developmental programs; the neural retina (NR) and retinal-pigmented epithelium (RPE). Studying how GRNs guide the differentiation of these tissues is an essential step to better understand the molecular bases of retinal degenerative diseases and the dynamics of embryonic development. Here we use the development of the optic cup in zebrafish (Danio rerio) as a vertebrate model organism, while continuing a well-established line of work that previously identified active cis-regulatory elements in each NR/RPE domain and captured the transition states of genetic networks using ATAC-seq and scRNA-seq epigenomics techniques respectively from different pools of sorted cells derived out from distinct domains of the optic cup at several stages of development. In this study we plan to functionally analyze a battery of candidate genes that are relevant transcription factor/targets in multiome analysis from ATAC-seq and slightly to strongly overexpressed in pseudobulk differential expression analysis from scRNAseq at 18-somite stage. Among the genes chosen for functional analysis, there are 5 from the retina, 6 from the RPE, 2 from the optic stem, 2 from the diencephalon and another 2 from the telencephalon, together with characterized genes whose expression are well-known to serve as experimental controls: vsx2, bhlhe40, vax1, gbx2 and emx1 respectively for each type of tissue.Methods: To carry out the functional analysis of the previously identified genes we are following a fluorescent in situ hybridization (FISH) protocol performe on wildtype zebrafish embryos fixed at 18h post-fertilization. This is a powerful and commonly used technique in whole-mounted embryos to assess phenotype, allowing us via super-resolution microscopy to examine temporal and spatial patterns of gene expression by visualizing its mRNA with a fluorescent riboprobe able to specifically recognize a DNA sequence. The first step was the identification of species-specific mRNA sequences and the design of primers for each candidate gene to reduce the risk of non-specific binding of the riboprobes or background signal. The synthesis of riboproteins was carried out after amplifying and purifying the cDNA sequences ordered
Feasibility of lignin-based platforms for the development of healthcare applications.
Get PDFLignin, a naturally occurring aromatic biomacromolecule, which is available in large amounts as a byproduct from pulping industries and lignocellulosic biorefineries, has attracted growing interest in recent years. The rise of these modern biorefineries is dedicated to converting lignocellulosic biomass into biofuels or advanced bioproducts. This, coupled with a growing emphasis on environmental sustainability, has sparked great interest in the valorization of lignin in various fields, including chemicals or materials. Natural polymers obtained from biological systems have been widely employed for the development of biomedical applications in recent decades. The most used materials for this purpose include alginate, chitosan, collagen, gelatin, and cellulose, among others. Unfortunately, lignin remains relatively underexplored in the biomedical field. The heterogeneity of natural and technical lignin samples, arising from the various lignocellulosic resources and extraction methods used to obtain this biomacromolecule, may hinder its applicability in healthcare applications. Additionally, the lack of in vivo biocompatibility and biodegradability studies to fully understand how this biomacromolecule can be degraded by the human body remains the biggest limitation to the use of lignin in the biomedical field. Despite these drawbacks mentioned earlier, lignin possesses several distinctive properties, such as antioxidant and antimicrobial capabilities, UV-absorbing capabilities, and low cytotoxicity, which are not found in other natural polymers. Antioxidant materials have potential for biomedical applications as they contribute to reduce the concentration of reactive oxygen species and free radicals, which can preclude wound healing (Barapatre et al., 2015). Furthermore, the incorporation of materials with antimicrobial properties in the development of healthcare applications, such as wound dressings, may help prevent infections and enhance wound healing (Domínguez-Robles et al., 2020). Therefore, this biomacromolecule can be a promising good candidate to be incorporated in the development of healthcare applications (Domínguez-Robles et al., 2020; Sugiarto et al., 2022). This work discusses some recent advances in the valorization of lignin through the development of drug delivery platforms
Los rituales en cuevas asociados a Artemis/Diana en la Antigüedad greco-romana (siglos VII a.C. - V d.C.)
Get PDFArtemis/Diana is a Greco-Roman divinity linked to nature, the wild, women and the liminal that does not adapt to classical civic norms. Due to this, in the mythical narratives and in the ritual practices, this goddess is associated with the nature of the cave, a topography far from the civilized, where are located entrances to underworld and human contact with the supernatural and the femenine fecundity. In this article I intend to analyze in detailthe symbolic figure of the goddess Artemis/Diana, as well as her cult linked to caves, paying special attention to female cults. This is due to the fact that, from a gender perspective, women in ancient times, whether they were divinities, faithful or priestesses in the Greco-Roman religion, have been victims of a long invisibility as an active religious subject by traditional historiography.Artemis/Diana es una divinidad greco-romana vinculada con la naturaleza, lo salvaje, las mujeres, lo liminal, y que no se adapta a las normas cívicas clásicas. Debido a estos aspectos, en las narrativas míticas y en las prácticas rituales, la diosa se asociaba con la naturaleza de la cueva, una topografía alejada de lo civilizado, en la que se ubicaban entradas al Inframundo, portales que ponen en contacto a los humanos con lo sobrenatural, con lo reproductivo y lo femenino. Este artículo pretende estudiar la figura simbólica de la diosa Artemis/Diana y su culto ligado a las cuevas, prestando especial atención a los cultos femeninos. Y es que, desde la perspectiva de género, las mujeres de la Antigüedad, ya sean divinidades, fieles o sacerdotisas, han sufrido una invisibilización como sujetos activos religiosos por parte de la historiografía tradicional
¿Una crisis con alternativa?:: Análisis de las rogationes rechazadas en la República romana entre el 70 y el 49 a.C.
Get PDFIt is commonly accepted by modern historiography that the end of the Roman Republic and the beginning of the Principate were both events that the political class of Rome was no table to comprehend nor solve. However, a detailed analysis of the 35 legislative proposals that were rejected shows that there was an important part of the Roman political class who was aware that some reform was needed to ensure the survival of the Republic. These legislative proposals were not passed due to several reasons, some of them being the opposition of the more conservative elements of Roman politics and the outbreak of violence.Existe la concepción en la historiografía moderna de que el fin de la República romana y el advenimiento del Principado fueron hechos de los que la élite política romana no fue capaz de percatarse o de solucionar. Sin embargo, el análisis detallado de las 35 propuestas de ley que no se aprobaron nos muestra que, al contrario de lo que se suele pensar, una parte importante de la clase política romana sí era consciente de que era necesario reformar ciertos aspectos de la República para garantizar su supervivencia. Estas propuestas de ley no llegaron a aprobarse por diversos factores, entre los que se encuentran la oposición de los sectores más conservadores de la política romana y el estallido de la violencia
Magisterio y obra de Luca Pacioli: alegoría de su retrato como alianza científica entre matemáticas, arte y contabilidad
Get PDFThe paper offers an updated analysis of the role played by Luca Pacioli in the Renaissance, especially Italian as an interdisciplinary nexus in the scientific alliance between Mathematics, Art and Trade, trough Accounting at that time. An interdisciplinary scientific vision on the role plays by the first for all the sciences and arts. What is founded in the content of De Divina Proportione (1509a), starting from golden ratio or number phi, developed in the Euclid´s Elements and adopted by Platon as “golden section” to define the Polyedra or “regular polygons”. The research is supported in a “systemic approach” made on the meaning and contents of the Portrait´s Pacioli; defining its elements and personal relationships that arise between the protagonists in the story of this alliance. With what can be deciphered the mysteries (the student identification and authorship portrait); at the same time that work builds basic ties caused the mentioned alliance, acting Pacioli as epicenter the same. In short, the work is a praise to the friendship and the scientific collaboration, and knowledge creation and transfer.El trabajo analiza el protagonismo desempeñado por Luca Pacioli en el Renacimiento, especialmente italiano, como nexo interdisciplinar en la alianza científica entre las Matemáticas, el Arte y el Comercio, a través de la Contabilidad, en ese tiempo. Una visión científica del papel interdisciplinar que desempeña la primera respecto al conjunto de las ciencias y de las artes. Lo cual se fundamente en el contenido de la Divina Proporción (Pacioli, 1509a), basada en la “proporción áurea” o número phi, formulado en los Elementos de Euclides y adoptado como “sección áurea” por Platón para definir los poliedros o cuerpos regulares. Análisis que se desarrolla con un “enfoque sistémico” de la investigación realizada sobre el significado y contenido del retrato de Pacioli, definiendo sus elementos y las relaciones personales que se derivan entre los protagonistas objeto del relato sobre la alianza científica generada. Enfoque que permite descifrar los enigmas sobre la identidad del alumno retratado y la autoría de la obra, a la vez que fundamentar los lazos básicos que dieron lugar a la citada alianza, actuando Pacioli como epicentro de la misma. En suma, el trabajo representa un elogio a la amistad y colaboración científica, y a la creación y transferencia de conocimiento
