Valorization of plant by-products in the biosynthesis of silver nanoparticles with antimicrobial and catalytic properties

Biosynthesis based on natural compounds has emerged as a sustainable approach for the production of metallic nanoparticles (MNP). The main objective of this study was to biosynthesize stable and multifunctional silver nanoparticles (AgNP) using different plant by-products as reducers and capping agents. Extracts obtained from Eucalyptus globulus, Pinus pinaster, Citrus sinensis, Cedrus atlantica and Camellia sinensis by-products, were evaluated. From all plant by-products tested, aqueous extract of eucalyptus leaves (EL), green tea (GT) and black tea (BT) were selected due to their higher antioxidant phenolic content and were individually employed as reducers and capping agents to biosynthesize AgNP. The green AgNP showed zeta potential values of -31.8 to -36.3 mV, with a wide range of particle sizes (40.6 to 86.4 nm), depending on the plant extract used. Green AgNP exhibited an inhibitory effect against various pathogenic bacteria, including Gram-negative (P. putida, E. coli, Vibrio spp.) and Gram-positive (B. megaterium, S. aureus, S. equisimilis) bacteria with EL-AgNP being the nanostructure with the greatest antimicrobial action. EL-AgNP showed an excellent photodegradation of indigo carmine (IC) dye under direct sunlight, with a removal percentage of up to 100\\% after 75 min. A complete cost analysis revealed a competitive total cost range of 8.0--9.0 \texteuro/g for the biosynthesis of AgNP.info:eu-repo/semantics/publishedVersio

Activity monitor placed at the non-paretic ankle is accurate in measuring step counts during community walking in post-stroke individuals : a validation study

Background: Different environmental factors may affect the accuracy of step-count activity monitors (AM). However, the validationconditions for AM accuracy largely differ from ecological environments.Objectives: To assess and compare the accuracy of AM in counting steps among poststroke individuals: during different locomotortasks, with AM placed at the nonparetic ankle or hip, and when walking in a laboratory or inside a mall.Design: Validation study.Settings: Laboratory and community settings.Participants: Twenty persons with chronic hemiparesis, independent walkers.Methods: First session: participants performed level walking (6-minute walk test [6MWT]), ramps, and stairs in the laboratory withAM placed at the nonparetic ankle and hip. Second session: participants walked a mall circuit, including the three tasks, with AMplaced at the nonparetic ankle. The sessions were video recorded.Main Outcome Measurements: Absolute difference between the steps counted by AM and the steps viewed on the video recordings(errors, %); occurrence of errors greater than 10%.Results: Median errors were similar for the 6MWT (0.86 [0.22, 7.70]%), ramps (2.17 [0.89, 9.61]%), and stairs (8.33 [2.65, 19.22]%)with AM at the ankle. Step-count error was lower when AM was placed at the ankle (8.33 [ 2.65, 19.22]%) than at the hip (9.26[3.25, 42.63]%, P = .03). The greatest errors were observed among the slowest participants (≤0.4 m/s) on ramps and stairs, whereassome faster participants (>1 m/s) experienced the greatest error during the 6MWT. Median error was slightly increased in the mallcircuit (2.67 [0.61, 12.54]%) compared with the 6MWT (0.50 [0.24, 6.79]%, P = .04), with more participants showing errors >10% dur-ing the circuit (7 vs 2, P = .05).Conclusions: Step counts are accurately measured with AM placed at the nonparetic ankle in laboratory and community settings.Accuracy can be altered by stairs and ramps among the slowest walkers and by prolonged walking tasks among faster walkers.Level of Evidence: III

Bats of the state of Minas Gerais, southeastern Brasil

Minas Gerais (MG) é o maior estado da região sudeste e sua localização em área de transição entre a faixa super úmida da costa e os ecossistemas mais áridos do centro-oeste brasileiro propicia a ocorrência de um rico mosaico de biomas e ecossistemas, incluindo o Cerrado, a Caatinga, a Mata Atlântica e áreas cársticas. Embora se saiba que a mastofauna de Minas Gerais é rica em espécies, não há uma lista de espécies de morcegos publicada, sendo esta a primeira compilação da fauna de quirópteros de MG. São aqui reunidos dados originais de inventários realizados independentemente pelos autores, informações da literatura e levantamento de espécimes depositados em várias coleções. Os resultados indicam a ocorrência de 77 espécies distribuídas em sete famílias em Minas Gerais, o que coloca o estado como o mais rico do sudeste brasileiro em número de espécies de morcegos. Essa riqueza surpreende também, devido ao fato constatado da escassez de dados disponíveis, conforme detectado no presente estudo. Grandes áreas do estado permanecem pouco conhecidas ou completamente desconhecidas em termos de sua quiropterofauna, incluindo ecossistemas frágeis associados à Caatinga, ao Cerrado e à Mata Atlântica, como os campos rupestres e áreas cársticas e não há sequer um estudo de longa duração. As coleções estudadas têm pouca representatividade em termos de espécimes oriundas do estado de Minas Gerais e são raras as séries sistemáticas oriundas de coletas no estado.Minas Gerais is the largest state in the Southeastern of Brazil, and its location in the transition between the humid coastal Atlantic Forest and the drier Western and central Brazilian countryside allows the occurrence of a rich mosaic of biomes and ecosystems that includes the Cerrado, the Caatinga, the Atlantic Forest, and karstic environments. This work is the first comprehensive compilation of the bat fauna of Minas Gerais state, Southeastern Brazil, including original data from surveys conducted independently by the authors, and published information documented with data from several museum collections. Although large areas of MG remains unsampled, unknown and/or unprotected, long term studies are virtually inexistent, and systematic inventories have not been documented to date, our results reveal high bat species richness for the state, with 77 species distributed in seven families. This indicates that MG has more bat species recorded than other Southeastern Brazilian states, a result that contrasts with the noticeable paucity of data for the state. The bat diverstity kept in museums does not mirror the actual bat diversity of MG, which thus urges to be properly acessed. Additionally, the collections examined were poorly represented in specimens from Minas Gerais and systematic series are rare

Drilling tool geometry evaluation for reinforced composite laminates

In this work, a comparative study on different drill point geometries and feed rate for composite laminates drilling is presented. For this goal, thrust force monitoring during drilling, hole wall roughness measurement and delamination extension assessment after drilling is accomplished. Delamination is evaluated using enhanced radiography combined with a dedicated computational platform that integrates algorithms of image processing and analysis. An experimental procedure was planned and consequences were evaluated. Results show that a cautious combination of the factors involved, like drill tip geometry or feed rate, can promote the reduction of delamination damage

Tool effects on hybrid laminates drilling

Fiber reinforced plastics are increasing their importance as one of the most interesting groups of material on account of their low weight, high strength, and stiffness. To obtain good quality holes, it is important to identify the type of material, ply stacking sequence, and fiber orientation. In this article, the drilling of quasi-isotropic hybrid carbon +glass/epoxy plates is analyzed. Two commercial drills and a special step drill are compared considering the thrust force and delamination extension. Results suggest that the proposed step drill can be a suitable option in laminate drilling

Optimizing laryngeal pathology detection by using combined cepstral features

ABSTRACT There are several diseases that affect the human voice quality which can be organic or neurological. Acoustic analysis of voice features can be used as a complementary and noninvasive tool for the diagnosis of laryngeal pathologies. The degree of reliability and effectiveness of the discriminating process depends on the appropriate acoustic feature extraction. This work presents a parametric method based on cepstral features to discriminate pathological voices of speakers affected by vocal fold edema and paralysis from healthy voices. Cepstral, weighted cepstral, delta cepstral, and weighted delta cepstral coefficients are obtained from speech signals. A Vector Quantization is carried out individually for each feature in the classification process, associated with a distortion measurement. The goal is to evaluate a performance of a classifier based on the individual and combined cepstral features. The average, the product and the weighted average are the different combination strategies applied yielding a multiple classifier that is more efficient than each individual technique. To assess the accuracy of the system, 153 speech files of sustained vowel /ah/ (53 healthy, 44 vocal fold edema and 56 paralysis) of the Disordered Voice Database from Massachusetts Eye and Ear Infirmary (MEEI) are used. Results show that the employed parameters are complementary and they can be used to detect vocal disorders caused by the presence of vocal fold pathologies

Antimicrobial, Antiproliferative and Proapoptotic Activities of Extract, Fractions and Isolated Compounds from the Stem of Erythroxylum caatingae Plowman

In the study, we have examined the antitumor and antimicrobial activities of the methanol extract, the fractions, a fraction of total alkaloids and two alkaloids isolated from the stem of Erythroxylum caatingae Plowman. All test fractions, except the hexane fractions, showed antimicrobial activity on gram-positive bacteria and fungi. The acetate: methanol (95:5), acetate, chloroform and hexane fractions show the highest cytotoxicity activity against the NCI-H292, HEp-2 and K562 cell lines using MTT. The absence of hemolysis in the erythrocytes of mice was observed in these fractions and 6β-Benzoyloxy-3α-(3,4,5- trimethoxybenzoyloxy) tropane (catuabine B). Staining with Annexin V-FITC and JC-1 was used to verify the mechanism of action of the compounds of E. caatingae that showed cytotoxicity less than 30 μg/mL in leukemic cells. After 48 h of incubation, we observed that the acetate: methanol (95:5), acetate, and chloroform fractions, as well as the catuabine B, increased in the number of cells in early apoptosis, from 53.0 to 74.8%. An analysis of the potential of the mitochondrial membrane by incorporation of JC-1 showed that most cells during incubation of the acetate: methanol (95:5) and acetate fractions (63.85 and 59.2%) were stained, suggesting the involvement of an intrinsic pathway of apoptosis

Teacher performance evaluation: conflict, uncertainties and the search for meaning(s)

O texto que propomos parte de uma pesquisa longitudinal, realizada em Portugal entre 2008 e 2010, com professores do 1º Ciclo do Ensino Básico. Procura evidenciar os conflitos e incertezas que a avaliação do desempenho docente tem produzido e a busca de sentido(s) para esta avaliação e para o ‘ser professor/a’. A implementação de sistemas de avaliação do desempenho dos professores insere-se na procura de soluções para esta inquietação. Foi o que aconteceu em Portugal, em Janeiro de 2007, com a publicação em Diário da República do novo Estatuto da Carreira Docente e o Decreto que regulamentava a Avaliação do Desempenho Docente. As tensões emergiram entre docentes e Ministério da Educação, agudizaram-se com a tomada de consciência da problemática da avaliação do desempenho dos docentes com impacto na carreira profissional e provocaram incertezas e desmotivação face ao sentido do trabalho docente com impacto na identidade profissional dos professores.This article stems from a longitudinal research carried out with primary school teachers in Portugal between 2008 and 2010. The research sought to identify the conflicts and uncertainties, which have been caused by the evaluation of teacher performance, as well as to search for meaning(s) related to that evaluation and to ‘being a teacher’. The implementation of systems for the evaluation of teacher performance fits into the search for solutions to that concern. This is what happened in Portugal, in January 2007, when the new Statute of the Teaching Profession and the law to regulate Teacher Performance Assessment were published in Diário da República – the official government publication. Tensions arose between teachers and the Ministry of Education and they were aggravated by an awareness of how the problem of teacher performance evaluation would impact on the professional career of teachers and how it would cause uncertainties and demotivation concerning the vocation of teaching and its subsequent impact on the professional identity of teachers

Sex differences in axial spondyloarthritis: data from a Portuguese spondyloarthritis cohort

Background: Axial spondyloarthritis (axSpA), particularly ankylosing spondylitis was historically considered a male’s disease and has been under-recognized in women. Emerging evidence reveals sex differences in pathophysiology, disease presentation and therapeutic efficacy. Objective: To identify differences between sexes in a Portuguese cohort of patients with axSpA regarding clinical manifestations, disease activity, functional capacity, patient related outcomes and presence of sacroiliitis on x-ray or magnetic resonance imaging. Methods: Patients with ≥18 years fulfilling the ASAS- Assessment of Spondyloarthritis International Society classification criteria for axSpA registered in the electronic Rheumatic Diseases Portuguese Register (Reuma.pt) were included in this multicentric cross-sectional study. Sociodemographic data, clinical features and imaging were collected from the first record in Reuma.pt. These variables were compared between sexes using Mann-Whitney test and Chi-Square test. Variables with a significant association with variable sex were considered in the multiple variable analysis to adjust the sex effect on the outcome variables. Statistical analysis was performed with R version 4.0.2 and p<0.05 was considered statistically significant. Results: A total of 1995 patients were included, 1114 (55.9%) men and 881 (44.1%) women. Men had an earlier disease onset (25.1 vs 28.4, p<0.001), were younger at diagnosis (26.9 vs 30.4, p<0.001) and were more frequently smokers (32.1% vs 15.7%, p<0.001). Comparing to women, men had worse Bath Ankylosing Spondylitis Metrological Index scores (4.0 vs 3.4, p<0.001), higher levels of C-Reactive Protein (10.5 vs 6.9 mg/L, p<0.001) and were more often Human Leukocyte Antigen-B27 positive (67.8% vs 54%, p<0.001). In contrast, women more frequently had inflammatory bowel disease (8.8% vs 4.9%, p=0.004), higher levels of erythrocyte sedimentation rate (25.0 vs 21.0mm/h, p=0.003) and worse patient-related outcomes- Bath Ankylosing Spondylitis Disease Activity Index (5.7 vs 4.5, p<0.001), Patient Global Assessment (60.0 vs 50.0, p<0.001) and fatigue (6.2 vs 5.0, p<0.001). Discussion: In this large multicentric study from a Portuguese axSpA cohort, we confirmed sex differences in patients with axSpA. This work brings awareness to these differences, resulting in less underdiagnosis and misdiagnosis, optimizing treatment strategies, and improving outcomes in axSpA.publishe