1,906 research outputs found

    Robust computer vision system for marbling meat segmentation

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    In this study, we developed a robust automatic computer vision system for marbling meat segmentation. Our approach can segment muscle fat in various marbled meat samples using images acquired with different quality devices in an uncontrolled environment, where there was external ambient light and artificial light; thus, professionals can apply this method without specialized knowledge in terms of sample treatments or equipment, as well as without disruption to normal procedures, thereby obtaining a robust solution. The proposed approach for marbling segmentation is based on data clustering and dynamic thresholding. Experiments were performed using two datasets that comprised 82 images of 41 longissimus dorsi muscles acquired by different sampling devices. The experimental results showed that the computer vision system performed well with over 98% accuracy and a low number of false positives, regardless of the acquisition device employed

    Evaluation of the supramolecular interaction of Congo red with cucurbiturils using mass spectrometry and spectroscopic methods

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    The ability of cucurbit[n]urils (CB[n]) to decolourise aqueous solutions of the azo dye Congo red (CR) was described more than a century ago alongside the first synthesis of CB[n]. No subsequent studies of the nature of the physical interactions have been reported despite the interest in using CB[n] as adsorbents for the removal of CR and related organic dyes from wastewaters. In the present work the supramolecular interaction between CB[n] (n = 7, 8) and CR was studied by electrospray ionisation mass spectrometry (ESI-MS), 1H NMR, and solid-state characterisation of isolated complexes. Under positive ESI, the formation of host–guest complexes in the gas phase was not observed, suggesting that CR anions do not interact with the portals and the nonpolar inner cavity of the CB[n] molecules. Conversely, under negative ESI, 1 : 1 and higher order (1 : 2, 2 : 1, 3 : 1 and 2 : 2) CR: CB[7] and CR: CB[8] adducts were detected, which is attributed to interaction between CR and the outer surface hydrogens of CB[n]. Solid-state supramolecular adducts between CB[n] and CR were isolated from aqueous media under either ambient conditions, giving structures denoted as CR@CB[n](RT), or hydrothermal (100 ºC) conditions, giving structures denoted as CR@CB[n](100). The adducts were characterised by elemental and thermogravimetric analyses (TGA), powder X-ray diffraction (PXRD), and spectroscopic methods (FT-IR, FT-Raman, 13C{1H} CP MAS NMR, UV/vis and near-IR absorption, fluorescence excitation and emission). The interaction conditions and acid content of the starting CB[n] influenced the protonation state of CR molecules. CR@CB[7](RT) contained only unprotonated CR, while CR@CB[8](100) contained exclusively protonated CR (ammonium and azonium/quinoid structures). Other adducts contained mixtures of protonated/unprotonated forms.publishe

    Atividade antinociceptiva e estudo toxicológico de extrato aquoso de Egletes viscosa Lessa (Asteraceae)

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    Egletes viscosa Less (Asteraceae), popularmente conhecida como "macela" ou "macela-da-terra", é uma planta largamente usada na medicina popular devido as suas propriedades: anti-inflamatória, bactericida, antidiarréica, mio-relaxante, anti-espasmódica, antinociceptiva, digestiva e anti-viral. Análise fitoquímica do extrato aquoso da Egletes viscosa (AEEV) mostrou elevada presença de flavonóides. Este estudo examinou o potencial antinociceptivo do AEEV em roedores usando diferentes concentrações (100, 200 and 400 mg/kg, p.o.). Os resultados mostraram significante efeito antinociceptivo quando testadas as doses (200 mg/kg-pEgletes viscosa Less (Asteraceae), popularly known as "macela" or "macela-da-terra", is a plant widely used in popular medicine due to its anti-inflammatory, bactericidal, antidiarrhoea, mio-relaxant, antispasmodic, antinociceptive, digestive, and anti-viral properties. Phytochemical screening of aqueous extract of Egletes viscosa (AEEV) revealed the high presence of flavonoids. This study examined the oral antinociceptive potential of AEEV in rodents using different concentrations (100, 200, and 400 mg/kg, p.o.). The results showed significant antinociceptive action when tested in writhing (200 and 400 mg/kg-

    The significance of cephalopod beaks as a research tool: An update

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    The use of cephalopod beaks in ecological and population dynamics studies has allowed major advances of our knowledge on the role of cephalopods in marine ecosystems in the last 60 years. Since the 1960's, with the pioneering research by Malcolm Clarke and colleagues, cephalopod beaks (also named jaws or mandibles) have been described to species level and their measurements have been shown to be related to cephalopod body size and mass, which permitted important information to be obtained on numerous biological and ecological aspects of cephalopods in marine ecosystems. In the last decade, a range of new techniques has been applied to cephalopod beaks, permitting new kinds of insight into cephalopod biology and ecology. The workshop on cephalopod beaks of the Cephalopod International Advisory Council Conference (Sesimbra, Portugal) in 2022 aimed to review the most recent scientific developments in this field and to identify future challenges, particularly in relation to taxonomy, age, growth, chemical composition (i.e., DNA, proteomics, stable isotopes, trace elements) and physical (i.e., structural) analyses. In terms of taxonomy, new techniques (e.g., 3D geometric morphometrics) for identifying cephalopods from their beaks are being developed with promising results, although the need for experts and reference collections of cephalopod beaks will continue. The use of beak microstructure for age and growth studies has been validated. Stable isotope analyses on beaks have proven to be an excellent technique to get valuable information on the ecology of cephalopods (namely habitat and trophic position). Trace element analyses is also possible using beaks, where concentrations are significantly lower than in other tissues (e.g., muscle, digestive gland, gills). Extracting DNA from beaks was only possible in one study so far. Protein analyses can also be made using cephalopod beaks. Future challenges in research using cephalopod beaks are also discussed.info:eu-repo/semantics/publishedVersio

    A Simulação e a Videoconferência no Ensino de Enfermagem

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    The objective of this study was to compare the learning outcomes of undergraduate nursing students who used simulated low fidelity teaching strategies with the results of those who used high fidelity simulated teaching videoconference. This is an experimental study carried out with undergraduates nursing students from Brazil which were divided into two groups and submitted to different distance education strategies: Virtual Learning Environment (AVA) and videoconference. The data were collected through questionnaires and theoretical and theoretical-practical evaluation. In general terms, this work compared the two groups of students, which had been randomly distributed and submitted to simulated low fidelity teaching (17) and to the videoconference of the simulated high fidelity training and its respective debriefing (27). The present study was carried out following the ethical precepts. The Free and Informed Consent Term was used. The students reported that VLE and video conferencing aided their learning. It was also observed that the learning performance of the students submitted to the simulation of low fidelity was better than those who attended the videoconference of the simulated high fidelity training and its respective debriefing. It is concluded that the simulated teaching is an effective teaching strategy that promotes the participation of the student as an actor of his learning.O objetivo deste estudo foi comparar os resultados da aprendizagem de estudantes de graduação em enfermagem que utilizaram estratégias de ensino simulado de baixa fidelidade com os resultados dos que usaram videoconferência do ensino simulado de alta fidelidade. Trata-se de um trabalho experimental realizado com graduandos de enfermagem do Brasil, os quais foram divididos em dois grupos e submetidos a diferentes estratégias de educação a distância: Ambiente Virtual de Aprendizagem (AVA) e videoconferência. Os dados foram coletados por meio de questionários e avaliação teórica e teórico-prática. Em linhas gerais, foram comparados os dois grupos de estudantes, os quais haviam sido distribuídos aleatoriamente e submetidos ao ensino simulado de baixa fidelidade (17) e à videoconferência do treino simulado de alta fidelidade e seu respectivo debriefing (27). O estudo foi realizado seguindo os preceitos éticos. Utilizou-se o Termo de Consentimento Livre e Esclarecido. Os estudantes relataram que o AVA e a videoconferência auxiliaram no seu aprendizado. Observou-se ainda que foi melhor o desempenho da aprendizagem dos alunos submetidos à simulação de baixa fidelidade do que o daqueles que assistiram à videoconferência do treino simulado de alta fidelidade e seu respectivo debriefing. Conclui-se que o ensino simulado é uma estratégia de ensino eficaz que promove de modo efetivo a participação do aluno como ator de seu aprendizado

    Evaluation of the potential association of SOHLH2 polymorphisms with non-obstructive azoospermia susceptibility in a large European population

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    Non-obstructive azoospermia (NOA) or spermatogenic failure is a complex disease with an important genetic component that causes infertility in men. Known genetic factors associated with NOA include AZF microdeletions of the Y chromosome or karyotype abnormalities; however, most causes of NOA are idiopathic. During the last decade, a large list of associations between single-nucleotide polymorphisms (SNP) and NOA have been reported. However, most of the genetic studies have been performed only in Asian populations. We aimed to evaluate whether the previously described association in Han Chinese between NOA and two SNPs of the SOHLH2 gene (involved in the spermatogenesis process) may also confer risk for NOA in a population of European ancestry. We genotyped a total of 551 NOA patients (218 from Portugal and 333 from Spain) and 1,050 fertile controls (226 from Portugal and 824 from Spain) for the genetic variants rs1328626 and rs6563386 using TaqMan assays. To test for association, we compared the allele and genotype frequencies between cases and controls using an additive model. A haplotype analysis and a meta-analysis using the inverse variance method with our data and those of the original Asian study were also performed. No statistically significant differences were observed in any of the analyses described above. Therefore, considering the high statistical power of our study, it is not likely that the two analysed SOHLH2 genetic variants are related with an increase susceptibility to NOA in the European population.info:eu-repo/semantics/publishedVersio
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