Fluctuation dynamics of a single magnetic chain

"Tunable" fluids such as magnetorheological "MR" and electrorheological "ER" fluids are comprised of paramagnetic or dielectric particles suspended in a low-viscosity liquid. Upon the application of a magnetic or electric field, these fluids display a dramatic, reversible, and rapid increase of the viscosity. This change in viscosity can, in fact, be tuned by varying the applied field, hence the name "tunable fluids". This effect is due to longitudinal aggregation of the particles into chains in the direction of the applied field and the subsequent lateral aggregation into larger semisolid domains. A recent theoretical model by Halsey and Toor "HT" explains chain aggregation in dipolar fluids by a fluctuation-mediated long-range interaction between chains and predicts that this interaction will be equally efficient at all applied fields. This paper describes video-microscopy observations of long, isolated magnetic chains that test HT theory. The measurements show that, in contrast to the HT theory, chain aggregation occurs more efficiently at higher magnetic field strength (H0) and that this efficiency scales as H0½. Our experiments also yield the steady-state and time-dependent fluctuation spectra C(x,x')≡ [h(x)-h(x')]²>½ and C(x,x',t,t')≡ ½ for the instantaneous deviation h(x,t) from an axis parallel to the field direction to a point x on the chain. Results show that the steady-state fluctuation growth is similar to a biased random walk with respect to the interspacing ͉ |x-x'| along the chain, C(x,x')≈|x-x'| α, with a roughness exponent α =0.53±0.02. This result is partially confirmed by Monte Carlo simulations. Time-dependent results also show that chain relaxation is slowed down with respect to classical Brownian diffusion due to the magnetic chain connectivity, C(x,x',t,t')≈|t-t'|β, with a growth exponent β=0.35±0.05<½. All data can be collapsed onto a single curve according to C(x,x',t,t')≈|x-x'| α ψ (|t-t'| / |x-x'| z ), with a dynamic exponent z= α /β≅ 1.42

Fatique alarms in intensive care: describing the phenomenon through integrative literature review

Objective: To analyze scientific publications about alarm monitoring and alarm fatigue phenomenon in intensive care. Methods: Integrative review of literature held in databases Lilacs, PubMed and SciELO. Results: After analyzing the productions elucidate the concepts and definitions of the phenomenon, predisposing factors and strategies to minimize them, the relationship with patient safety, achieving time frame 1993 to June 2010. Fatigue alarm occurs when a large number of alarms covers those clinically significant, enabling relevant alarms are disabled, silenced or ignored by staff. The excessive number of alarms makes indifferent staff, reducing your alertness, leading to distrust of the sense of urgency of alarms, resulting in lack of response to alarms relevant. Conclusion: The technological apparatus requires attention of professionals to ensure patient safety serious

Chitosan/virgin coconut oil-based emulsions doped with photosensitive curcumin loaded capsules: a functional carrier to topical treatment

In recent years, there has been a growing interest in developing smart drug delivery systems based on natural resources combined with stimulus-sensitive elements. This trend aims to formulate innovative and sustainable delivery platforms tailored for topical applications. This work proposed the use of layer-by-layer (LbL) methodology to fabricate biocompatible photo-responsive multilayer systems. These systems are composed of a polyoxometalate inorganic salt (POM) ([NaP5W30O110]14â) and a natural origin polymer, chitosan (CHT). Curcumin (CUR), a natural bioactive compound, was incorporated to enhance the functionality of these systems during the formation of hollow capsules. The capsules produced, with sizes between 2â 5μm (SEM), were further dispersed into CHT/VCO (virgin coconut oil) emulsion solutions that were casted into molds and dried at 37 â ¦C for 48 h.The system presented a higher water uptake in PBS than in acidic conditions, still significantly lower than that earlier reported to other CHT/VCO-based systems. The drug release profile is not significantly influenced by the medium pH reaching a maximum of 37% ± 1% after 48 h. The antioxidant performance of the designed structures was further studied, suggesting a synergistic beneficial effect resulting from CUR, POM, and VCO individual bioactivities. The increased amount of those excipients released to the media over time promoted an increase in the antioxidant activity of the system, reaching a maximum of 38.1% ± 0.1% after 48 h. This work represents a promising step towards developing advanced, sustainable drug delivery systems for topical applications.The authors would like to thank the contributions to this research from the project “TERM RES Hub–Scientific Infrastructure for Tissue Engineering and Regenerative Medicine”, reference PINFRA/22190/2016 (Norte-01-0145-FEDER-022190), funded by the Portuguese National Science Foundation (FCT) in cooperation with the Northern Portugal Regional Coordination and Development Commission (CCDR-N), for providing relevant lab facilities, state-of-the art equipment and highly qualified human resources

Art and the creative process in education for engineers: a study focused on Utfpr, Brazil

Esta pesquisa teve como objetivo estudar a função da arte na promoção da criatividade nos processos formativos dos acadêmicos de engenharia da Universidade Tecnológica Federal do Paraná (UTFPR), enquanto fator de inovação tecnológica. Desenvolvida no âmbito do paradigma construtivista, foi utlizado o método qualitativo, nomeadamente o estudo de caso. A fonte de recolha de dados utlizada foi a entrevista semiestruturada, tendo os respetivos guiões sido desenvolvidos no âmbito da Teoria das Representações Sociais de Serge Moscovici (1978). O campo de estudo foi constituído por 10 estudantes e egressos, por 10 professores, coordenadores e diretores de Ensino e do Campus de Pato Branco, pelo Reitor da universidade e por 4 empresários. A técnica de tratamento de dados utlizada foi a análise de conteúdo. De entre as principais conclusões, saliente-se que os entrevistados entendem que a arte pode contribuir para a melhoria da formação académica do estudante de engenharia uma vez que proporciona novos pontos de vista, promove a criatividade e a inovação. Defendem também que atividades como o teatro podem estimular a capacidade criativa em ambiente universitário dos engenheiros já que permite a promoção da comunicação e expressão, desenvolvimento de um profissional mais completo e favorece a capacidade de abstração. Por último, entendem que a arte e suas diversas expressões estéticas são importantes na formação acadêmica do engenheiro no que diz respeito à criação de projetos inovadores, uma vez que favorece a inspiração, a inovação e a integração em equipes.This research aimed to study the role of art in promoting creativity in the educational processes of engineering students at the Federal Technological University of Parana (UTFPR), as a factor of technological innovation. Developed under the constructivist paradigm, the qualitative method was used, namely the case study. The data collection source used was the semi-structured interview, and the respective scripts were developed within the scope of Serge Moscovici's Theory of Social Representations (1978). The field of study consisted of 10 students and graduates, 10 professors, coordinators and directors of Teaching and Campus of Pato Branco, the University's Rector and 4 entrepreneurs. The data treatment technique used was content analysis. Among the main conclusions, it is noteworthy that the interviewees understand that art can contribute to the improvement of the academic education of engineering students, since it provides new points of view, promotes creativity and innovation. They also defend that activities such as theater can stimulate the creative capacity of engineers in a university environment, as it allows for the promotion of communication and expression, the development of a more complete professional and favors the capacity for abstraction. Finally, they understand that art and its various aesthetic expressions are important in the academic education of engineers with regard to the creation of innovative projects, as it favors inspiration, innovation and integration into teams.info:eu-repo/semantics/publishedVersio

A structural equation model of self-regulation and healthy habits as an individual protective tool in the context of epidemics evidence from COVID-19

The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.Objective: The present study aims to explore the mediation role of self-regulation on health-related behaviors adoption or maintenance, mental health, and well-being during the COVID-19 confinement in a sample of adults in Portugal. Design: One-hundred fifty individuals (118 females, 32 males; Mage = 33.57 year; SD = 12.71) filled an online survey to assess self-regulation, healthy behaviors, mental health, and well-being perception, during the early months of the pandemic (June–August, 2020). Main Outcome Measures: Self-regulation capacity, adoption or maintenance of healthy habits, mental health, including stress management, and the perception of one’s well-being were evaluated using a structural equation model (SEM). Results: Self-regulation had direct effects on healthy habits and mental health and indirect effects on well-being and mental health mediated by healthy habits. In specific, a positive direct effect on healthy habits (β = 0.497, p < 0.001) and a negative direct effect on mental health (β = −0.428, p < 0.001); and a positive indirect effect on well-being perception, mediated by healthy behaviors and mental health (β = 0.253, p = 0.003), and a negative indirect effect on mental health, mediated by healthy habits (β = −0.208, p = 0.003). Additionally, healthy habits exerted direct effects on well-being perception and mental health. A positive direct effect on well-being perception (β = 0.254, p = 0.012), and a negative direct effect on mental health (β = −0.418, p < 0.001) were further observed. No direct effect of mental health was observed in well-being perception (β = −0.199, p = 0.068). Finally, a negative correlation was observed between self-regulation and weeks of confinement (r = −0.208, p = 0.021). Conclusion: Self-regulation seems to be a good indicator of adopting a healthy lifestyle and better mental health and well-being in the context of the COVID-19 pandemic. Future preventive actions and interventions to build long-term global preparedness for future health emergencies, such as COVID-19, should explore the importance of self-regulation as an important individual and collective protective factor.This study was conducted at the Psychology Research Center (PSI/01662), School of Psychology, University of Minho, and supported by the Portuguese Foundation for Science and Technology (FCT) through the Portuguese State Budget (UIDB/PSI/01662/2020). This study was also supported by the project 2018-1-PT01-KA201-047417, funded by the ERASMUS+ Education and Training National Agency. SS was supported by the project PTDC/PSI-ESP/28228/2017, funded by the Portuguese Foundation for Science and Technology (FCT) and the European Regional Development Fund (FEDER). AS-F was supported by FCT and the Portuguese Ministry of Science, Technology and Higher Education, through the national funds, within the scope of the Transitory Disposition of the Decree No. 57/2016, 29th of August, amended by Law No. 57/2017 of 19 July. MF was supported by the UMINHO/BIM-CNCG/2021/29 Research Fellowship funded by the Portuguese Foundation for Science and Technology (FCT). SC acknowledges the Psychology for Positive Development Research Center (PSI/04375), Lusíada University of Porto, Porto, Portugal, supported by national funds through the Portuguese Foundation for Science and Technology, I.P., and the Portuguese Ministry of Science, Technology and Higher Education (UID/PSI/04375/2019)

Substantive rationality of impression management:an analysis of corporate reports of JBS

Objective: To investigate the substantive rationality inherent to the practice of impression management (IM). Originality/value:Based on the taxonomy created by Merkl-Davies and Brennan (2011), it is analyzed: 1. the discussion under the sociological perspective; and 2. the actions of substantive rationality in the management of impressions that can manifest through actions of symbolic management. This study responds to the call of Merkl-Davies et al. (2011) by putting into practice an unconventional analytical model based on the use of the corporate reports (annual and sustainability) of the company JBS with special attention to the “Carne Fraca” [Weak Meat] Operation. Design/methodology/approach: A content analysis of the accounting narratives of JBS’ corporate reports between 2015 and 2018 was carried out.Findings: Accounting narratives suggest evidence of IM and substantive rationality. The preparers of the corporate reports used substantive rationality to legitimize the company’s actions, with the most significant manifestations of this practice in the 2017 report, the year of the “Carne Fraca” operation. The implications of this research lie in demonstrating evidence that guides companies regarding the use of accounting narratives to convince society of their actions as consistent with the structure of social rules and norms. Furthermore, we emphasize that the accounting narratives must be analyzed with caution since they can be elaborated under the influence of the manager’s opportunistic behavior.info:eu-repo/semantics/publishedVersio

Screening of chemical composition, antimicrobial and antioxidant activities in pomegranate, quince, and persimmon leaf, peel, and seed: valorization of autumn fruits by-products for a one health perspective

Antimicrobial resistance is increasing globally and is now one of the major public health problems. Therefore, there is a need to search for new antimicrobial agents. The food industry generates large amounts of by-products that are rich in bioactive compounds, such as phenolic compounds, which are known to have several health benefits, including antioxidant and antimicrobial properties. Thus, we aimed to characterize the phenolic compounds present in pomegranate, quince, and persimmon by-products, as well as their antioxidant and antimicrobial activities. Phenolic compounds were extracted from pomegranate, quince, and persimmon leaves, seeds, and peels using a mixture of ethanol/water (80/20). The polyphenol profile of the extracts was determined by high-performance liquid chromatography. The antioxidant activity of the extracts was determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and cupric reducing antioxidant capacity (CUPRAC) methods. Antimicrobial susceptibility was evaluated using the Kirby–Bauer disk diffusion method. In general, leaves showed higher concentrations of phenolics than the peel and seeds of fruits. In total, 23 phenolic compounds were identified and quantified, with sanguiin and apigenin-3-O-galactoside being present in the highest concentrations. Leaf extracts of pomegranate showed higher antioxidant activities than the other components in all methods used. In general, all extracts had a greater antimicrobial activity against Gram-positive bacteria. Persimmon leaf and seed extracts inhibited a greater number of bacteria, both Gram-positive and -negative. The lowest minimum inhibitory concentration (MIC) detected among Gram-positive and -negative bacteria was 10 mg/mL for pomegranate peel and leaf extracts against Staphylococcus aureus and S. pseudintermedius and for pomegranate leaf extract against Escherichia coli. Our results reinforce the need to value food industry by-products that could be used as food preservatives and antibiotic adjuvants against multiresistant bacteria.This work was supported by projects UIDP/00772/2020 and LA/P/0059/2020, funded by the Portuguese Foundation for Science and Technology (FCT), and by LAQV-REQUIMTE, which is financed by national funds from FCT/MCTES (UIDB/50006/2020 and UIDP/50006/2020). This work was also supported by National Funds from the FCT–Portuguese Foundation for Science and Technology, under project UIDB/04033/2020, as also to CIMO (UIDB/00690/2020 and UIDP/00690/2020), SusTEC (LA/P/0007/2020), and for L. Barros institutional contract; to FEDER through the Regional Operational Program North 2020, under the Project GreenHealth, Norte-01-0145-FEDER-000042.info:eu-repo/semantics/publishedVersio