146 research outputs found
Desenvolvimento do processo de vazamento em coquilhas rotativas
Tese de mestrado integrado. Engenharia Mecânica. Faculdade de Engenharia. Universidade do Porto. 201
The Inhibitory Effects of Curcuma longa
The essential oil from Curcuma longa L. was analysed by GC/MS. The major components of the oil were ar-turmerone (33.2%), α-turmerone (23.5%) and β-turmerone (22.7%). The antifungal activities of the oil were studied with regard to Aspergillus flavus growth inhibition and altered morphology, as preliminary studies indicated that the essential oil from C. longa inhibited Aspergillus flavus Link aflatoxin production. The concentration of essential oil in the culture media ranged from 0.01% to 5.0% v/v, and the concentration of curcumin was 0.01–0.5% v/v. The effects on sporulation, spore viability, and fungal morphology were determined. The essential oil exhibited stronger antifungal activity than curcumin on A. flavus. The essential oil reduced the fungal growth in a concentration-dependent manner. A. flavus growth rate was reduced by C. longa essential oil at 0.10%, and this inhibition effect was more efficient in concentrations above 0.50%. Germination and sporulation were 100% inhibited in 0.5% oil. Scanning electron microscopy (SEM) of A. flavus exposed to oil showed damage to hyphae membranes and conidiophores. Because the fungus is a plant pathogen and aflatoxin producer, C. longa essential oil may be used in the management of host plants
Nutritional composition and bioactivity of Umbilicus rupestris (Salisb.)Dandy: An underexploited edible wild plant
The inclusion of edible wild plants in human diet has been receiving an increasing attention, as they represent an
easily accessible source of nutrients, vitamins and antioxidants. In this work, the leaves of Umbelicus rupestris
(Salisb.) Dandy, an edible species for which only scarce data is available in literature, were thoroughly evaluated
for its nutritional profile, chemical characterization and bioactive properties. Being considered a succulent plant,
the leaves revealed a very high content of moisture, with several beneficial compounds, including omega-3
polyunsaturated fatty acids, tocopherols and different polyphenols. A total of twelve flavonoids, three phenolic
acids and one phenylpropanoid glucoside were identified in the decoction and/or hydroethanolic extracts, with
most of them being described for the first time in this plant. Both extracts showed antioxidant activity and
potential to inhibit some of the assayed bacteria, while not presenting cytotoxic effects on a non-tumour primary
cell culture.The authors are grateful to the Foundation for Science and
Technology FCT, Portugal) and FEDER under Programme PT2020 for
financial support to CIMO (UID/AGR/00690/2019). L. Barros, R.C.
Calhelha, and A. Fernandes thank national funding by FCT, P.I.,
through the institutional scientific employment program-contract. For
their contracts. This work was also funded by FEDER-Interreg España-
Portugal programme through the project 0377_Iberphenol_6_E.info:eu-repo/semantics/publishedVersio
Chemical composition and bioactive properties of the wild edible plant Raphanus raphanistrum L.
Recently, there has been an interest regarding the consumption of wild edible plants in modern diets. However,
there is still scarce information about several wild vegetables traditionally consumed. Therefore, this work aims
on documenting the nutritional and chemical composition of wild radish (Raphanus raphanistrum L.), as well as
its bioactive potential. Results showed that wild radish is a potential source of beneficial compounds, including
vitamin E, polyunsaturated fatty acid (particularly α-linolenic acid) and different phenolic compounds, in which
fourteen phenolics were identified, with kaempferol-3,7-O-di-rhamnoside being the most abundant. The
bioactive potential was exploited using hydroethanolic and decoction extracts. Both proved to inhibit several
Gram-positive and Gram-negative bacteria and revealed antioxidant activity, while cytotoxicity against nontumor
cell was not observed. In general, results evidence the interest in recovering the use of this wild vegetable
as part of a varied diet, which can bring several health benefits.info:eu-repo/semantics/publishedVersio
Using the Non-linear Behavior of the Brokaw Bandgap Voltage Reference Cell to Linearize Resistance Temperature Detectors (RTD)
Resistance temperature detectors (RTD) present second and third order non-linearities, and a linear signal processing circuit which converts the voltage on a Pt-100 RTD to an output voltage with 10 mV/oC presents a maximum non-linearity error of 1.07 oC (10.7 mV) in the 0 to 85 oC temperature range. These non-linearities can be corrected digitally, but there are applications where a simple analog linearization can be used with advantages, as in the case of a direct interface of an RTD sensor with a 4-20 mA current loop transducer. The intrinsic curvature of the Brokaw bandgap voltage reference cell, caused by the non- linear variation of the bipolar transistor's VBE with temperature, can be used to create a compensation voltage that can be used to reduce the non-linearity of the signal processing circuit of resistance temperature. A discrete Brokaw bandgap reference cell using a bipolar analog array LM3046 and a high precision op-amp was designed, and the calculated values of the final circuit indicate that the non-linearity of the signal conditioning circuit of a Pt-100 RTD is reduced by one order of magnitude (down to approximately 0.14 oC) in the 0-85 oC temperature range
Capturas e resistências à terceirização: estudo com trabalhadores de uma universidade pública
RÉSUMÉ
Cet article montre les résultats d'une recherche qui a été effectuée avec des employés externalisés aux fonctions de services généraux dans une université publique bresiliénne. Le principal objectif de l’étude était d'analyser les risques de souffrance pathogène dans le travail de ces personnes. La Psychodynamique du Travail a été le référentiel théorique utilisé et la méthodologie choisie a été basée sur l'Inventaire de Risques de Souffrance Pathogène au Travail (IRST, em Portuguais), utilisé avec un échantillon de 139 personnes dans l’université. l’instrument analyse trois facteurs spécifiques des situations de travail: utilité, indignité et reconnaissance. Les résultats de la recherche révèlent, essentiellement, que les travailleurs montrent des sentiments d’indignité devant leur réalité de travail, et ils aimeraient avoir plus de reconnaissance pour leur activités. Les facteurs qui produisent plus de risques pour la santé des participants sont liés aux conditions de travail physique et les cas de harcèlement moral. La Psychodinamique souligne que le processus d'externalisation produit la fragmentation des collectifs du travail, pouvant affaiblir la construction de l'identité ouvrière, et générer des maladies, aspects qui ont été confirmés par les résultats de la recherche. Nous concluons que le processus d’externalisation est producteur de forts risques pour la santé de ces travailleurs et, justifiée par cette recherche, productions académiques sur ce thème sont de plus en plus nécessaires.
MOTS-CLE: Processus d'externalisation. Souffrance pathogène. Psychodynamique du Travail.ABSTRACT
This article presents results of one research made with outsourced workers with general services functions of one Brazilian public university. The main objective of the study was to analyse the risks of pathogenic suffering in the work of these people. The Psychodynamics of Work was the theoretical reference used and the chosen methodology was based in the Inventory of Risks of Pathogenic Suffering at Work (IRST, in Portuguese), applied on a sample of 139 people in the university. The used instrument analyses three specifc factors of wok situations: utility, indignity and recognition. The results of this research reveals, mainly, that these workers show feelings of indignity related to their laboral reality, and that they would like to feel more recognized for your activities. The factors that generate more risks to the health of the participants are linked to the physical conditions of work and the situations of moral harassment. The Psychodynamics considers the outsourcing process as a device that results in the fragmentation of the collectives of work, fact that can weaken the workers identity construction and generate illnesses, what is confirmed by the results obtained in this research. It is concluded that the outsourcing process produces strong risks for the workers health and, because of it, academic productions about this subject are increasingly necessary.
KEYWORDS: Outsourcing process. Pathogenic Suffering. Psychodynamics of Work.RESUMO
Este artigo apresenta resultados de uma pesquisa realizada com trabalhadores terceirizados do setor de limpeza de uma universidade pĂşblica brasileira. O estudo teve como principal objetivo analisar os riscos de sofrimento patogĂŞnico no trabalho desses sujeitos. A Psicodinâmica do Trabalho foi o referencial teĂłrico utilizado e a metodologia escolhida baseou-se no Inventário de Riscos de Sofrimento PatogĂŞnico no Trabalho (IRST), aplicado em uma amostra de 139 sujeitos na prĂłpria universidade. O instrumento utilizado analisa trĂŞs fatores especĂficos das situações de trabalho: utilidade, indignidade e reconhecimento. Os resultados da pesquisa indicam, principalmente, que tais trabalhadores apresentam sentimentos de indignidade em relação Ă realidade laboral, assim como gostariam de se sentir mais reconhecidos por suas atividades. Os fatores que mais geram riscos Ă saĂşde dos participantes estĂŁo ligados Ă s condições fĂsicas do trabalho e Ă s situações de assĂ©dio moral. A Psicodinâmica considera a terceirização como dispositivo que resulta na fragmentação dos coletivos de trabalho, o que pode fragilizar a construção identitária dos trabalhadores e provocar adoecimentos, o que vai ao encontro dos resultados obtidos na pesquisa. Conclui-se que o processo de terceirização Ă© produtor de fortes riscos para a saĂşde desses trabalhadores e, por isso, produções acadĂŞmicas sobre esta temática se fazem cada vez mais necessárias.
PALAVRAS-CHAVE: Terceirização. Sofrimento patogênico. Psicodinâmica do Trabalho
Istmos en conductos mesiales de primeros molares inferiores.
El estudio de la anatomĂa y complejidad de los conductos radiculares tiene relevancia clĂnica y puede relacionarse con causas frecuentes de fracaso endodĂłntico. Los istmos son comuni- caciones estrechas entre conductos, consideradas áreas de difĂcil acceso1, impidiendo la remociĂłn de remanentes bacterianos y tejido pulpar2 , volviĂ©ndose un desafĂo para los endodoncistas. No hay lite- ratura de mĂ©todos de limpieza y modelado eficiente de estas áreas. La incidencia reportada de istmos es de 75-100% 1 en raĂces mesiales de primeros molares superiores y 83%3 de raĂces distales de mo- lares inferiores
Hadronic sizes and observables in high-energy scattering
The functional dependence of the high-energy observables of total cross
section and slope parameter on the sizes of the colliding hadrons predicted by
the model of the stochastic vacuum and the corresponding relations used in the
geometric model of Povh and H\"ufner are confronted with the experimental data.
The existence of a universal term in the expression for the slope, due purely
to vacuum effects, independent of the energy and of the particular hadronic
system, is investigated. Accounting for the two independent correlation
functions of the QCD vacuum, we improve the simple and consistent description
given by the model of the stochastic vacuum to the high-energy pp and pbar-p
data, with a new determination of parameters of non-perturbative QCD. The
increase of the hadronic radii with the energy accounts for the energy
dependence of the observables.Comment: Latex, using Revtex.style . 2 ps figures. To be published in Physical
Review D , July 199
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