308 research outputs found
A new species of Corydoras Lacépède (Siluriformes: Callichthyidae) from the Rio Tapajós basin and its phylogenetic implications
A new species of Corydoras is described from tributaries of the rio Arinos, rio Teles Pires and rio Preto, all in the rio Tapajós basin. The new species is a member of a group that includes 36 species with spots on the body. Within this group, the new species can be readily distinguished by having a smaller dorsal-fin spine than the first three subsequent soft dorsal-fin rays; pectoral, pelvic and anal fins hyaline; dorsal-fin interradial membrane hyaline; rounded spots on trunk restricted to dorsolateral body plates and dorsal portion of ventrolateral body plates, not reaching the base of pelvic and anal fins. The new species can be further distinguished from Corydoras xinguensis by having spots with diffuse edges, and from all other species of spotted Corydoras except C.multimaculatus, by the absence of ventral platelets. A phylogenetic analysis recovered the new species plus Corydoras metae and C.araguaiensis in a clade sharing the presence of a pointed process on the maxilla for insertion of the retractor tentaculi muscle. In addition, the presence in the new species of an elongated anterior portion of the mesethmoid and a triangular uncinate process of the epibranchial 3 suggests a close relationship with Corydoras metae.Uma nova espécie de Corydoras é descrita dos tributários dos rios Arinos, Teles Pires e Preto, bacia do rio Tapajós. A nova espécie é membro de um grupo com pontilhados no corpo que inclui 36 espécies. Dentro desse grupo, a nova espécie pode ser facilmente distinguida pelo espinho dorsal menor que os três primeiros raios ramificados da nadadeira dorsal; nadadeiras peitorais, pélvicas e anal hialinas; membranas inter-radiais da nadadeira dorsal hialina; presença de pontilhados redondos no tronco restritas as placas dorsolaterais do corpo e porções dorsais das placas ventrolaterais não alcançando a base das nadadeiras pélvicas e anal. A nova espécie pode ser distinguida de Corydoras xinguensis por pontilhados com margens difusas e das demais espécies de Corydoras com pontilhado, exceto em C.multimaculatus, pela ausência de pequenas placas ventrais. Uma análise filogenética recuperou a nova espécie mais Corydoras metae e C.araguaiensis em um agrupamento compartilhando a presença de um processo pontiagudo para inserção do músculo retractor tentaculi no maxilar. A porção anterior do mesetmóide alongada e o processo uncinado do epibranquial 3 triangular indicam uma relação mais próxima com Corydoras metae
Music Segmentation and Similarity Estimation Applied to a Gaze-Controlled Musical Interface
Assistive technology, especially gaze-controlled, can promote accessibility, health care, well-being and inclusion for impaired people, including musical activities that can be supported by interfaces controlled using eye tracking. Also, the Internet growth has allowed access to a huge digital music database, which can contribute to a new form of music creation. In this paper, we propose the application of Music Information Retrieval techniques for music segmentation and similarity identification, aiming at the development of a new form of musical creation using an automatic process and the optimization algorithm Harmony Search to combine segments. These techniques for segmentation and similarity of segments were implemented in an assistive musical interface controlled by eye movement to support musical creation and well-being. The experimental results can be found in [https://bit.ly/2Zl7KSC]
Ulva rigida valorization into poly(3-hydroxybutyrate), organic acids and functional ingredients
Halomonas elongata 1H9T is a moderate halophilic strain able to produce poly(3-hydroxybutyrate) (P(3HB)), a biodegradable plastic, and gluconic acid, a valuable organic acid with wide industrial applications. In this work, the green alga Ulva rigida was used as platform to produce cultivation substrates for microbial conversion as well as functional ingredients, targeting its full valorization. The liquor obtained by autohydrolysis presented the highest concentration of oligosaccharides and protein, being an interesting feedstock to produce functional ingredients. The acid and/or enzymatic hydrolysis liquors are adequate as substrates for microbial processes. Shake flask assays with H. elongata revealed that the N-rich liquor produced after acidic treatment was the best suited for cell growth while the N-poor liquor produced by the enzymatic treatment of acid-pretreated algae residues produced the highest P(3HB) titers of 4.4 g/L. These hydrolysates were used in fed-batch cultivations as carbon and protein sources for the co-production of gluconic acid and polymer achieving titers of 123.2 g/L and 7.2 g/L, respectively. Besides gluconic acid, the Krebs cycle intermediate 2-oxoglutaric acid, also called alpha-ketoglutaric acid (KGA), was produced. Therefore, the co-production of P(3HB) and acids may be of considerable interest as an algal biorefinery valorization strategy.This research was funded by Fundação para a Ciência e Tecnologia (FCT) project number (PTDC/BII-BIO/29242/2017). Funding received from FCT—Fundação para a Ciência e Tecnologia, I.P., in the scope of the project UIDB/04565/2020 and UIDP/04565/2020 of the Research Unit Institute for Bioengineering and Biosciences—iBB and the project LA/P/0140/2020 of the Associate Laboratory Institute for Health and Bioeconomy—i4HB is acknowledged. Funding received from FCT under the scope of the strategic funding of UID/BIO/04469/2020 unit and LABBELS—Associate Laboratory in Biotechnology, Bioengineering and Microelectromechanical Systems, LA/P/0029/2020 project is also acknowledged.info:eu-repo/semantics/publishedVersio
Novel approaches of nanoceria with magnetic, photoluminescent, and gas-sensing properties
The modification of CeO2 with rare-earth elements opens up a wide range of applications as biomedical devices using infrared emission as well as magnetic and gas-sensing devices, once the structural, morphological, photoluminescent, magnetic, electric, and gas-sensing properties of these systems are strongly correlated to quantum electronic transitions between rare-earth f-states among defective species. Quantitative phase analysis revealed that the nanopowders are free from secondary phases and crystallize in the fluorite-type cubic structure. Magnetic coercive field measurements on the powders indicate that the substitution of cerium with lanthanum (8 wt %), in a fluorite-type cubic structure, created oxygen vacancies and led to a decrease in the fraction of Ce species in the 3+ state, resulting in a stronger room-temperature ferromagnetic response along with high coercivity (160 Oe). In addition to the magnetic and photoluminescent behavior, a fast response time (5.5 s) was observed after CO exposure, indicating that the defective structure of ceria-based materials corresponds to the key of success in terms of applications using photoluminescent, magnetic, or electrical behaviors.Fil: Rocha, Leandro S.R.. Universidade Federal do São Carlos; BrasilFil: Amoresi, Rafael A.C.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Moreno, Henrique. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Ramirez, Miguel A.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Ponce, Miguel Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Foschini, Cesar R.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Longo, Elson. Universidade Federal do São Carlos; BrasilFil: Simões, Alexandre Z.. Universidade Estadual Paulista Julio de Mesquita Filho; Brasi
Production of lipid rich-extracts from Chlorella vulgaris using ohmic heating
Microalgae biomass is a promising raw material for several bioproducts suitable for food, energy and pharmaceutical
industries. The aim of the present work was to optimize the extraction of bioactive compounds from Chlorella
vulgaris using Ohmic Heating (OH).
A rotatable central composite design for two factors was used to assess the effects of temperature and solvent (% ethanol
in water) on lipid extraction yields and fatty acid profile. OH extraction experiments were powered by low-frequency (50
Hz) and high-frequency (25 kHz) to identify the presence of non-thermal effects and its influence on composition and
bioactive properties of the generated extracts.
Lipid extraction using OH was successfully optimized with the best extraction conditions found at 70 ºC for 5 min using 88
% ethanol as a solvent. No effect on the application of the electrical frequencies was observed. These conditions allowed
to recover up to 87 % of lipids from biomass, polyunsaturated fatty acids (PUFAs) accounting for 43 % of the extracted
lipids against 26 % of saturated fatty acids (SFAs). The fatty acid profile reveals that C16:2, C16:3, C18:2 and C18:3
correspond to the PUFAs extracted from Chlorella vulgaris. Regarding lipid extraction yields OH was statistically equivalent
to conventional heating (COV); however, in terms of heating kinetics, OH reaches the required extraction temperature 5
times faster than COV.
Results showed that OH has potential to be applied as a treatment for the production of Chlorella vulgaris PUFAs richextracts
providing high recovery yields with reduced treatment times and less energy consumption.This study was supported by: the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and project OH2O – PTDC/EQU-EQU/029145/2017; by FEDER funds through COMPETE2020 – Programa Operacional Competitividade e Internacionalização (POCI) under the scope of Project Algavalor (POCI-01-0247-FEDER-035234; LISBOA-01-0247-FEDER-035234; ALG-01-0247-FEDER-035234) and OH2O (POCI-01-0145-FEDER-029145); AgriFood XXI R & D & I project, operation number NORTE-01-0145-FEDER-000041, co-financed by the European Regional Development Fund (FEDER) through NORTE 2020 (Northern Regional Operational Program 2014/2020). Ricardo N. Pereira acknowledge FCT for its Assistant Research contract obtained under CEEC Individual 2017. Leandro Madureira acknowledges FCT for its PhD fellowship (SFRH/BD/151474/2021) obtained under MIT Portugal Programinfo:eu-repo/semantics/publishedVersio
Trojan-like internalization of anatase titanium dioxide nanoparticles by human osteoblast cells
Dentistry and orthopedics are undergoing a revolution in order to provide more reliable, comfortable and long-lasting implants to patients. Titanium (Ti) and titanium alloys have been used in dental implants and total hip arthroplasty due to their excellent biocompatibility. However, Ti-based implants in human body suffer surface degradation (corrosion and wear) resulting in the release of metallic ions and solid wear debris (mainly titanium dioxide) leading to peri-implant inflammatory reactions. Unfortunately, our current understanding of the biological interactions with titanium dioxide nanoparticles is still very limited. Taking this into consideration, this study focuses on the internalization of titanium dioxide nanoparticles on primary bone cells, exploring the events occurring at the nano-bio interface. For the first time, we report the selective binding of calcium (Ca), phosphorous (P) and proteins from cell culture medium to anatase nanoparticles that are extremely important for nanoparticle internalization and bone cells survival. In the intricate biological environment, anatase nanoparticles form bio-complexes (mixture of proteins and ions) which act as a kind of ‘Trojan-horse’ internalization by cells. Furthermore, anatase nanoparticles-induced modifications on cell behavior (viability and internalization) could be understand in detail. The results presented in this report can inspire new strategies for the use of titanium dioxide nanoparticles in several regeneration therapies
Music Segmentation and Similarity Estimation Applied to a Gaze-Controlled Musical Interface
Assistive technology, especially gaze-controlled, can promote accessibility, health care, well-being and inclusion for impaired people, including musical activities that can be supported by interfaces controlled using eye tracking. Also, the Internet growth has allowed access to a huge digital music database, which can contribute to a new form of music creation. In this paper, we propose the application of Music Information Retrieval techniques for music segmentation and similarity identification, aiming at the development of a new form of musical creation using an automatic process and the optimization algorithm Harmony Search to combine segments. These techniques for segmentation and similarity of segments were implemented in an assistive musical interface controlled by eye movement to support musical creation and well-being. The experimental results can be found in [https://bit.ly/2Zl7KSC]
Electrical transport mechanisms of Neodymium-doped rare-earth semiconductors
This study reports the electrical properties of Nd-doped cerium oxide (CeO2) films synthesized by microwave assisted hydrothermal using a two-point probe technique. Positron annihilation lifetime spectroscopy studies evidenced that, as the Nd content rises, a structural disorder occurs. This is caused by an increase in oxygen vacancies surrounded with Nd (defective clusters), with the mean lifetime components ranging between 290 and 300 ps. Particle size estimation showed values from 8.6 to 28.9 nm. Along with the increase of neodymium impurities, also the conductivity increases, due to the hopping conduction mechanism between defective species. This gives rise to a response time of only 6 s, turning these materials candidates to realize gas sensor devices. Ab initio investigations showed that the improved electric conduction is boosted mostly by the reduced Nd2+ than the Ce3+, where the oxygen vacancies play a fundamental role.Fil: Vaz, Isabela C. F.. Federal University of Itajubá; BrasilFil: Macchi, Carlos Eugenio. Universidad Nacional del Centro de la Provincia de Buenos Aires; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Somoza, Alberto Horacio. Universidad Nacional del Centro de la Provincia de Buenos Aires; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rocha, Leandro S. R.. Universidade Federal do São Carlos; BrasilFil: Longo, Elson. Universidade Federal do São Carlos; BrasilFil: Cabral, Luis. Universidade Estadual de Campinas; BrasilFil: da Silva, Edison Z.. Universidade Estadual de Campinas; BrasilFil: Simões, Alexandre Zirpoli. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Zonta, Giulia. Università di Ferrara; ItaliaFil: Malagu, Cesare. Università di Ferrara; ItaliaFil: Desimone, Paula Mariela. Universidad Nacional de Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Ponce, Miguel Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina. Universidad Nacional de Mar del Plata; ArgentinaFil: Moura, Francisco. Federal University of Itajubá; Brasi
- …