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Review and prospects of geotextiles
2024 - BEZERRA, INDIRA Q.M.; DEL MASTRO, NELIDA L.
With the increase of global environmental changes and intensive anthropogenic activities, it is extremely important to maintain and improve soil function. Soil erosion is a naturally occurring process that affects all landforms. Different structures and forms of geotextiles are available to geotechnical engineers. Geotextiles in the form of woven and nonwoven structures are mostly used in various geo-engineering applications. This article focus on how the use of geotextiles have grown during the last decades and the importance of a particular material to be base of geotextiles, babassu (Attalea speciosa Mart. ex Spreng, Arecaceae) that is a palm with socioeconomic and ecologic importance found in humid tropical areas in Brazil.
OCT in prosthodontics
2023 - MORAES, PAULO N.L. de; MORAIS, MARCIA C.D. de; ZEZELL, DENISE M.
Prosthodontics is a specialty of dentistry that aims to recover lost dental elements, through fixed or removable prosthetic elements, installed on osseointegrated implants and/or remaining teeth or roots. The interface between prosthetic elements and tissues of the oral cavity (hard tissues, such as bone and teeth, or soft tissues, such as gingiva and mucous membranes), as well as between different prosthetic surfaces (implants and abutments, crowns, cores, resins and cements) has always been a critical factor for the success of the treatment, with long-term maintenance of function and aesthetics. The analysis of these interfaces is routinely performed through clinical examination and with the use of radiographs, but the accuracy of this analysis is relative. The use of optical coherence tomography (OCT) has shown to be suitable for the analysis of these interfaces and also the integrity of different types of prosthesis, due to its micrometric resolution, and for being a real-time and non-invasive technique, preserving the integrity of the evaluated structures, being able to clinically assess them over time.
OCT in cariology
2023 - ZEZELL, DENISE M.; ANA, PATRICIA A.
This chapter will review one of the main aspects of OCT applications in dentistry, which is the caries processes and wear. The changes in the mineral content during demineralization and remineralization of dental hard tissues alter the optical properties of enamel and dentin, such as refractive index, increase in scattering and changes in light polarization, which allows the quantification of demineralization degree by OCT, resulting in the possibility of quantitatively monitoring lesion progress or remineralization with better spatial resolution than the conventional radiographic imaging methods. The use of optical clearing agents on the surface of enamel and dentin can reduce the scattering and reflection of the surfaces, reaching deeper optical penetration, which improves the quality, contrast and sensitivity of OCT images. Clinical studies showed the possibility of evaluating the presence of subsurface lesions in different sites, as well as quantifying their severity, but the development of new probes that can image posterior interproximal regions and devices that allow the positioning of the probes in a standardized way are still in progress.
Polymeric Nanogels and Nanoparticles in Medical Applications
2024 - KADLUBOWSKI, SLAWOMIR; LIMA, CAROLINE S.A. de; FERREIRA, ARYEL H.
Nanogels and polymeric nanoparticles have been intensively studied for diverse applications due to their unique and tuneable properties. Nanogels are hydrogelsdthree-dimensional network of polymer chains with water filling the spaces between themdin nanometer size, which allows them to penetrate biological barriers and be of high interest for several medical applications. Polymeric nanoparticles are differentiated from nanogels by the swelling property. While nanogels have high capacity of water absorption that may lead to size changes, polymeric nanoparticles are mostly a solid mass. Both, nanogels and nanoparticles may be obtained from synthetic and natural polymers though different synthesis processes. The radiation-induced intramolecular crosslinking was proposed as a great alternative, eliminating the need of toxic crosslinking agents and providing a final sterile material. In this review, we intended to present a focused discussion on the radiation-induced synthesis technologies, the most frequent used polymers to obtain nanogels and nanoparticles, and their biomedical applications showcasing their potential to revolutionize healthcare.
O antropoceno e o direito ambiental
2023 - SODRE, MARCELO G.; RODRIGUES, ELAINE A.
Fungal nanobionics
2023 - THIPE, VELAPHI C.; BATISTA, JORGE G.S.; LEBRE, DANIEL T.; LUGAO, ADEMAR B.; KATTI, KATTESH V.
Fungi have proven to be one of the most beneficial microorganisms that have contributed and continue to play a pivotal role in human civilization. The nexus between mycology and nanotechnology provides a cornucopia of metabolites that can be utilized in nanotechnology to usher in a separate branch of study—"Myconanobiotechnology.” This is achieved by fungal nanobionics, which centers fungi as nanofactories for the large-scale industrial production of nanoparticles for the development of new next-generation products with industrial, agricultural, medicinal, and consumer application prospects in a wide range of sectors that stem from pharmaceuticals, agriculture, and energy, thus envisaging a completely different paradigm in relation to revolutionizing technologies. In this chapter, we cover a plethora of the biogenic-mediated synthesis of nanoparticles intracellularly and extracellularly with an in-depth understanding of the principles that govern fungal nanobionics. Furthermore, we provide an in-depth knowledge of the most recent advances in mycoinnovations that utilize fungal nanobionics in the ubiquitous role they play in a myriad of applications stemming from disinfectants, food packaging material additives, biosensors, medicine, cosmetics, textiles, electronics, composites, agricultural products (effective antimicrobial agents in nanofertilizers and nanopesticides), and most recently in energy through renewable, sustainable biofuel production.
Aplicação terapêutica das células-tronco na medicina veterinária
2023 - SANTOS, ENRICO J.C.
Os constantes avanços clínicos e laboratoriais na área da medicina veterinária vêm propiciando aos animais uma maior longevidade. O aumento da expectativa de vida tende a resultar em uma maior incidência de patologias, assim como o surgimento de novas doenças até o momento não existentes ou de baixa frequência. Atualmente, a manutenção da qualidade de vida dos animais na terceira idade é um dos principais desafios no âmbito da medicina veterinária. Perante o presente quadro, constantes estudos científicos básicos, préclínicos e clínicos vêm sendo desenvolvidos tendo por meta a implementação de tratamentos inovadores para enfermidades nas quais as terapias convencionais têm se mostrado insuficientes ou ineficazes. Dentre estes, um dos que têm se mostrado mais promissores é a terapia celular com células-tronco, a qual pode ser definida como arte de se administrar células vivas ao corpo de um receptor objetivando o tratamento de uma condição médica específica.
Copper-Based Nanomaterials for Biologically Relevant Compounds
2024 - BATISTA, JORGE G. dos S.; RODRIGUES, MURILO A.V.; FREITAS, LUCAS F. de; FONSECA, ANA C.M.; RODRIGUES, ADRIANA de S.; CRUZ, CASSIA P.C. da; THIPE, VELAPHI C.; LUGAO, ADEMAR B.
Copper-based nanomaterials have emerged as a new platform in various scientific domains due to their unique physicochemical, biological, and compatibility properties. This review explores the multifaceted applications of copper nanomaterials in the areas of biosensing, drug delivery, cancer therapy, and environmental remediation. The innovative role of copper nanomaterials in biosensors and their exceptional sensitivity and specificity in detecting biomolecules are discussed. Moreover, the potential applications of copper-based nanomaterials in drug delivery systems, highlighting the controlled and targeted release of therapeutic agents’ approaches are explored. In the domain of cancer theragnostic, copper nanomaterials exhibit promising results thus offering practical tools for early diagnosis and advanced treatment modalities. Furthermore, the antimicrobial properties of copper nanoparticles are explored, emphasizing their importance in combating microbial threats and promoting a new era in antimicrobial research. Copper-based nanomaterials could have a significant role in environmental and bioremediation applications. The strong catalytic activity of copper nanoparticles makes them ideal candidates for environmental remediation. In summary, this comprehensive review consolidates the latest advances in copper nanomaterials research, providing valuable information for scientists and researchers involved in diverse fields to promote the development of new applications and technologies.
Mulheres no âmbito nuclear impulsionando a integração latino-americana
2024 - DEL MASTRO, NELIDA L.; GERVASONI, JUANA L.
A energia nuclear é utilizada para a geração de energia elétrica, a produção de radioisótopos, a dessalinização de água do mar e para a produção de hidrogênio. As técnicas nucleares e isotópicas contribuem para a preservação dos recursos hídricos e do solo e para controlar as pragas, garantir a inocuidade dos alimentos e maior segurança alimentar, bem como melhorar a produção e sanidade pecuárias. A organização de mulheres no âmbito nuclear (Women in nuclear-WiN) tem como uma das suas funções dar a conhecer ao público os benefícios que a aplicação da energia nuclear pode trazer em todas as possíveis aplicações. Essa ação vai contribuir para superar restrições de aquela parte do público que é reticente sobre o uso dessa tecnologia e contribuir à integração latinoamericana. Também, são apresentados cruzamentos de dados do número de publicações relacionadas, que ajudam analisar objetivamente s tendência de essa integração.
Evolution of dispersed fuel used for research and test reactors
2024 - GOMES, D.S.
Currently, 222 research reactors are operating in 53 countries in Brazil, four units. Nuclear fuel type used in research reactors depends on the thermal power level, classified by power classes, such as critical and subcritical units operating below 1Kw, working from 1 kW to 1 MW, and over 1 Mw, being 28 facilities operating on a medium power spectrum from 1 MW up to 10Mw. Alternatively, they divided the research reactor into lowenriched uranium below 20% of U-235 and highly-enriched uranium over this limit. In the 1950s, the superheat section of the Fifth Boiling Reactor Experiment (BORAX-V) used enriched uranium (93 wt.% U-235) as uranium dioxide in a matrix of stainless steel. In sequence, it divided a fast dispersion fuel evolution into three ages. The 1950s predominated U–Al alloy. In the 1960s, the U3 O8 –Al and UAlx -Al followed the 1980s, focusing on high uranium density up to 4.8 gU/cm3 planned to U3 Si2 -Al and U10Mo/Al. Today, global research focuses on U-10Mo dispersion and monolithic forms. Many thermal physical features of dispersed fuels can help define the application field, mainly focused on neutron activation analysis and radiopharmaceutical production.
An investigation of the performance of triso fuel and molten fluoride salts
2024 - GOMES, D.S.
Public opinion has reached a growing consensus that nuclear energy could be an inflection point for mitigating global warming and the shortage of natural resources in the future. The energy demand suffers a rapid increase and can duplicate itself up to 2035. Since 2002, Generation IV has researched at least six designs to substitute nuclear power plants with forty years of operation. A fluoride hightemperature reactor is designed to use tri-structural fuel formed of graphite-matrixcoated particles with a mixture of lithium and beryllium fluorides as a coolant, commonly called FLiBe. However, concisely, the heat transfer models applied to nuclear reactors depend on the Prandtl number correlated to coolant and usage conditions. A pebblebed fluoride-salt-cooled high-temperature reactor, Mark-1, comprises a conceptual project developed at Berkeley in 2016. Then, it performs a theoretical analysis of the core reactor, where we review the thermal properties of fuel and coolant. It compares generation-IV reactor design analysis with options such as heavy liquid metals, coolants, molten salt reactors, and conventional fuels.
Analysis of the physical models used for nuclear ceramic fuel
2024 - GOMES, D.S.
Nuclear ceramics resist to radiation exposure and may change their thermal and mechanical properties. Many ceramic fuels, such as UO2 and mixed oxide (MOX), are the primary fuels used in the current commercial light water reactors. Fusion reactor use of low-activity ceramics, primarily silicon carbide, will eliminate the generation of large quantities of highly radioactive waste. Silicon carbides show desirable mechanical properties and corrosion resistance at high temperatures, making them essential for nuclear fuel cladding intended for a vast range of fuels in LWRs, Gas-cooled reactors use TRISO fuel at high temperatures. Generation IV reactors scheduled for 2035 have defined seven reactor types that will operate at higher temperatures with extended burn cycles, employing innovative fuels focusing on carbide UC and nitride UN. A review of the thermal and mechanical models used in the FRAPCON codes is presented.
Proteção radiológica
2024 - SOARES, MARIA R.; BATISTA, WILSON O.G.
Os autores Maria Rosangela Soares e Wilson Otto Gomes Batista apresentam uma abordagem holística, integrando os conceitos de física das radiações, metrologia, radiobiologia, regulamentos e ações de organismos nacionais e internacionais, visando à boa compreensão e ao cumprimento dos princípios fundamentais da proteção radiológica.
Smart electrolytes
2024 - SANTIAGO, ELISABETE I.; LINARES, JOSE J.
In this chapter, we will focus on polymeric electrolyte materials, widely used in low temperature electrochemical cells, both fuel cells and electrolyzers, in acid or alkaline environment. Within each section, each material will be described, with special emphasis on the durability studies and degradation issues observed. Special attention will be given to the proposal for overcoming the observed limitations.
Heat treatment influence on micromilling of additively manufactured titanium
2024 - GONCALVES, MARIA C.C.; MERGULHAO, MARCELLO V.; BATALHA, GILMAR F.; STOETERAU, RODRIGO L.
Recently, miniaturized products are being used as working tools by many fields, highlighting the medical and dental industries. With the development of Additive Manufacturing (AM) processes, these features can be produced with less material waste and with wide design possibilities by applying a ‘near-net-shape’ technique. Although, the AM parts require post-processing techniques to reach the required material properties, dimensions, and surface roughness and to reduce undesirable residual stresses. In this aspect, the micromilling process is usually applied to attain the desired dimensions and surface roughness and heat treatments to attain the desired material properties and to reduce residual stress. Nonetheless, the micromilling process can be done before or after the heat treatment. In this perspective, this research analyses the surface roughness results for the micromilled AM parts before and after the heat treatment, which is in important for planning the manufacturing route for these parts. Thus, this work aims to compare the surface roughness results of Sa, Sq, Ssk, Sku when performing the micromilling process on AM parts by Laser Powder Bed Fusion (LPBF), with and without heat treatment. For the experiments, the tool size, feed and cutting speed were varied in a full factorial design of experiments. After that, the surface roughness parameters were analyzed and compared for both workpieces. With the achieved results, it can be concluded that the surface texture (Ssk) for the heat-treated and non-heat-treated samples present a predominance of peaks. Also, there is a presence of inordinately high peaks and/or deep valleys on the surface (Sku), which can present an interference of the chips left on the surface not removed by the ultrasonic cleaning. By the analyses of the arithmetic mean deviation (Sa) and the root mean square height (Sq), a better surface quality was achieved when micromilling the samples before the heat treatment for greater tool size, for the specific set of parameters used. With the smaller tool size, a greater surface roughness was achieved if compared to the bigger tool size, though the difference between the samples were not expressive. Moreover, the results achieved in this work can be applied to improve the surface quality of the AM parts used in industry.
Polysaccharide-based nanotechnology approaches to deliver bioactive compounds for food applications
2023 - ROSALES, THIECLA K.O.; FABI, JOAO P.
Nanoencapsulation based on natural polysaccharides effectively protects and improves the bioavailability of different bioactive compounds. Food polysaccharides have essential functional properties to compose targeted delivery nanosystems in the intestine. This chapter describes the characteristics of the leading natural polysaccharides used as nanocarriers for application in food products. Also, it demonstrates the principal methodologies used for elaboration and applicability, indicating the characterization methods mechanisms for the formation and targeted release. The essential biomaterials for this purpose are chitosan, cellulose, and pectin, which can be used alone or combined with proteins to form nano-gels with multiple functionalities. Several methodologies can be used for preparation, such as molecular self-organization and ionic gelation. Nanoencapsulated bioactives based on these polysaccharides can be protected, maintain functional properties, thus increasing the absorption and bioavailability. Biocompatibility, biodegradability, and nontoxicity are the highlighted advantages of these biopolymers. In addition, they can be extracted from sustainable sources, such as industrial by-products. Several studies have proven the advantages and relevancy of biomaterials for protection against the environment, factors intrinsic to human digestion, and enhancing the beneficial effects of biologically active compounds. Nanoencapsulation based on polysaccharides effectively enables the inclusion of these compounds in foods or to develop new dietary supplements.
Perspectivas dos resíduos sólidos de saúde (RSS)
2023 - GONCALVES, MAX F.S.; LOPES, MARIA E.C.; MOL, MARCOS P.G.
Repositórios digitais institucionais
2023 - IGAMI, MERY P.Z.
Descreve-se a experiência do IPEN, objetivando compartilhar conhecimento e contribuir para o avanço do papel que os Repositórios digitais institucionais podem alcançar. O Instituto de Pesquisas Energéticas e Nucleares - IPEN - é um instituto público federal localizado em São Paulo, cuja missão é produzir conhecimento e tecnologia relacionados com as aplicações das técnicas nucleares e das ciências relacionadas, dedicando-se também à formação de recursos humanos, mediante um programa de Pós-Graduação. O relato diz respeito ao processo de migração da base de dados referencial de produção científica institucional, construída na década de oitenta, para o atual Repositório Digital (RD). A citada base de dados referencial foi organizada segundo padrões internacionais, reunindo e atribuindo um tratamento diferenciado à produção científica da instituição, desde a sua criação. Descreve-se essa organização e os atributos que facilitaram o processo de migração e que se tornaram fatores decisivos para o sucesso da atividade. Para funcionamento do atual RD, foram desenvolvidas funções e acrescentados metadados, além dos tradicionais, os quais se constituem em filtros, a fim de favorecer o controle, o monitoramento, a extração de relatórios e principalmente a interoperabilidade com o Sistema Gerencial Institucional, o SIGEPI. O RD fornece dados em tempo real e em fluxo contínuo, apresenta estatísticas de produtividade para a elaboração de indicadores científicos e informações gerenciais para subsidiar os gestores do IPEN. O RD foi construído dentro dos pressupostos do movimento de Acesso Aberto e, por meio de ações de valor agregado atribuído, tornou-se um instrumento de gestão do capital intelectual institucional. Descreve-se também o planejamento para futuras atividades a serem desenvolvidas com o RD.
Nanodiagnostic tools for mycotoxins detection
2022 - THIPE, VELAPHI C.; MENDES, GIOVANNA de O.A.; ALVES, VICTORIA M.; SOUZA, THAYNA; AJAYI, RACHEL F.; LUGAO, ADEMAR B.; KATTI, KATTESH V.
In recent decades, mycotoxin contamination of agricultural food items has garnered considerable attention because to their high acute or chronic toxicity in humans and animals, resulting from consumption and exposure duration to contaminated food or feed. This is exacerbated by the impact of the Covid-19 pandemic, civil wars, and conflicts (e.g., the Russia-Ukraine conflict, Yemen, Ethiopia, Afghanistan, and others), which further strain the food security and nutritional status of the most vulnerable demographic groups, which are predicted to continue to deteriorate due to health and socioeconomic factors. The presence of these mycotoxins in food and animal feed has a negative impact on public health and the economy; consequently, it is crucial to detect and quantify these toxins in agricultural lots. Maintaining food quality and minimizing adverse effects on human and animal health are dependent on early detection. Conventional techniques for detecting mycotoxins include enzyme-linked immunoassay (ELISA), gas chromatography (GC), thin-layer chromatography (TLC), and high-performance liquid chromatography (HPLC). Nanomaterial-based sensor technologies provide diverse mitigation methods for quantifying single or multiple analytes, as mycotoxin co-occurrence in a single matrix has become more common. In this chapter, we describe recent advancements in nanodiagnostic techniques that permit multiplex detection of mycotoxins on a single platform. In addition, we discuss certain commercially available lateral flow immunoassay (LFIA) test strips that often use gold nanoparticles (AuNPs) or quantum dots (QDs) as colored labels for signal amplification, as well as some commercial goods with nanoformulations used in agriculture. For the commercialization of nano-based assays (nanosensors), nanodisks (nanoparticles-based artificial sensing), and that may be used as point-of-care testing (POCT) devices for mycotoxin detection, it will be necessary to conduct additional research and make additional investments to overcome the difficulties identified.
Fabrication of green nanomaterials
2023 - THIPE, VELAPHI C.; FREITAS, LUCAS F.; LIMA, CAROLINE S.A.; BATISTA, JORGE G.S.; FERREIRA, ARYEL H.; OLIVEIRA, JUSTINE P.R. de; BALOGH, TATIANA S.; KADLUBOWSKI, SLAWOMIR; LUGAO, ADEMAR B.; KATTI, KATTESH V.
The purpose of this chapter is to discuss the production of biocompatible green nanomaterials for biomedical applications using green nanotechnology. To enhance drug loading and delivery, these nanomaterials are engineered with immunomodulatory ligands such as phytochemicals (Epigallocatechin gallate, Mangiferin, Resveratrol), proteins (albumin and papain), crosslinked hydrogels, and nanogels. The nanomaterials described herein are synthesized via redox potential of electron-dense phytochemicals that reduce metallic precursors to their stable corresponding nanoparticles and via water radiolysis with ionizing radiation as a green approach (due to the absence of any reducing agent) for use as radiosensitizers (albumin and papain nanoparticles) in nuclear medicine – theranostics applications. The phytochemicals facilitate the delivery of nanoparticles through receptor mediated endocytosis, while the proteins such as papain, due to their proteolytic action enhances the permeation of nanoparticles into tumor tissue, and albumin increase the pharmacokinetic efficiency of these nanoparticles. The nanoparticles developed have shown effectiveness against a variety of human cancers while posing no toxicity to normal tissue. Additionally, a pilot human clinical combing Ayurvedic medicine with green nanomedicine is given as a novel approach for treating breast cancer and other related illnesses. Finally, the importance of ecotoxicology for nanomaterials is discussed in order to provide safety data in relevant multiple species (fish, daphnia, algae, rodents, etc.) with paratope/epitope distributions for evaluating tissue cross-reactivity profiles in human tissues and to provide critical information on in vivo toxicity in order to predict the possible adverse effects of nanomaterials on human and environmental health as an effort to establish regulatory limits and ISO standards for nanomaterials.

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