Distinct stress responses to pyocyanin by planktonic and sessile Staphylococcus aureus UFPEDA 02 and Escherichia coli UFPEDA 224 / Respostas distintas ao estresse causado pela piocianina em células planctônicas e sésseis de Staphylococcus aureus UFPEDA 02 e Escherichia coli UFPEDA 224

Antimicrobial activity of pyocyanin against competing organisms of Pseudomonas aeruginosa is related to the oxidative stress that the compound promotes in susceptible cells. The objective of this work was to produce, extract and verify the activity of pyocyanin in planktonic and sessile forms from clinical strains, Staphylococcus aureus UFPEDA 02 and Escherichia coli UFPEDA 224. About 600 µg/mL of pyocyanin were obtained. The planktonic cells were highly sensitive. The MIC determined for S. aureus UFPEDA 02 and E. coli UFPEDA 224 were 18.75 and 37.5 µg/mL, respectively. The pyocyanin demonstrated biocidal effect against S. aureus UFPEDA 02. On the other hand, pyocyanin was not active in either sessile strain. The presence of the pigment allowed a greater adherence of the strains, forming more robust biofilms compared to the control. S. aureus UFPEDA 02 and E. coli UFPEDA 224 presented moderate and high hydrophobicity, respectively. Glass and dolomite surfaces were tested in the in vitro biofilm test. Both strains formed the biofilm better on the dolomite surface, obtaining a cell concentration (MPN/cm2) in the order of 3 log units after 48h of incubation

Presence of filamentous fungi in powder and semiaqueous makeup / Presença de fungos filamentosos em maquiagens em pós e semissólidas

Makeup is used by a large portion of humanity and often misused or stored incorrectly, leading to contamination by microbes. The water content in cosmetics influences susceptibility to microbial contamination, which can represent health risks, as well as deterioration. The aim of this work was to isolate and identify filamentous fungi in samples of face powder, foundation, blush, and lipstick of eight popular brands in Brazil. A study of their composition identified a total of 106 ingredients. Of the products, 75% of the samples showed contamination by filamentous fungi. Penicillium was the most prevalent, followed by Rhizopus and Scopulariopsis. The presence of these pathogens suggests misuse in the production and manipulation of these cosmetics as well as high risk to users' health

Magnetic structure of a slow spreading ridge segment: Insights from near-bottom magnetic measurements on board a submersible

International audienceNear-bottom magnetic measurements on board submersible Nautile were carried out on the Mid-Atlantic Ridge 21 degrees 40'N segment, and deep-sea geomagnetic vector anomalies along 19 dive tracks were obtained by applying the processing method for shipboard three-component magnetometer data. A forward modeling technique using short-wavelength components of the anomalies arising from local topography and vertical motion of the submersible was designed to estimate the absolute magnetization intensity of the seafloor. In the vicinity of the spreading axis a considerable number of magnetization estimations are reliably confirmed by the high correlation between observed and modeled anomalies, whereas less reliable estimations are obtained off-axis, probably because the sediment buries the basement topography. The natural remanent magnetization (NRM) measured on basalt samples collected during these dives is compared with the magnetization from anomalies. Though both results give a similar range of magnetization intensity, no correlation is confirmed between them, possibly because the magnetization from anomalies represents laterally averaged seafloor magnetization, whereas the NRM has variations at the scale of individual pillow or lava pile. Equivalent magnetization inverted from the sea-surface magnetic anomalies shows axial magnetization increases significantly from the segment center to the segment ends. However, the results of eight dives conducted near the spreading axis at different locations along the segment show much less variation in magnetization intensity along the axis. We ascribe the high equivalent magnetization at segment ends to preferential serpentinization of peridotite near the segment ends and the associated formation of magnetite. The results of three across-axis transects composed of 15 dives running in the spreading direction can be consistently interpreted as recording geomagnetic paleointensity variations during the Brunhes epoch. Although magnetization lows are generally correspondent to periods of low paleointensity, they show deeper drop than predicted from the paleointensity variation

Life on a slippery slope: perceptions of health in adults with cystic fibrosis

This paper focuses on how adults with cystic fibrosis (CF) attending a specialist CF centre in the UK perceive their health. In common with many other genetic diseases, CF is traditionally conceptualised as a fatal childhood disease, yet the average survival age for those with CF has been steadily rising over the past half century. Thus it is now predicted that those born in 1990 will live on average for 40 years. To date, however, most sociological work has focused on children or adolescents affected by CF rather than on adults between the ages of 18 and 40, the focus of the study reported here. The paper shows that these adults' varying perceptions of health are related to the effects of CF, its treatment, and the context in which adults are placed. Four concepts of health are identified (health as 'normal', controllable, distressing and a release) along with certain styles, ways of coping and related strategies. Through these analytic distinctions the paper aims to make a contribution to the sociological understanding of lay concepts of health in adults with childhood or genetic disease

Exercise and quality of life in patients with cystic fibrosis: A 12-week intervention study

It was hypothesised that increased exercise capacity is related to improved quality of life (QoL) in patients with cystic fibrosis (CF). A 12-week individually tailored unsupervised aerobic exercise programme was offered to 42 patients with CF. At the start and at the end of the exercise programme, data on QoL, current exercise habits and preferences, anthropometric data, exercise test, and lung function test were collected. Adherence was observed by a heart rate (HR) monitor. A total of 24 patients accepted to be enrolled in the exercise programme and 14 completed the programme. Another 14 patients declined to be enrolled in the exercise programme but completed the Cystic Fibrosis Questionnaire for Adolescents and Adults (CFQ-R 14+). Four patients did not want to participate at all. The 14 patients completing the exercise programme had a significantly increased VO2max, but they showed no significant change in total QoL score. However, the scores in the domain of treatment burden and emotional functioning increased significantly. There was no significant difference in QoL and lung function between patients participating in the exercise programme (n = 24) and non-participants (n = 14). A 12-week individually tailored unsupervised aerobic exercise programme where HR monitors were used significantly affected VO2max. Improvement in QoL could not be demonstrated in this study

A geomagnetic record over the last 3.5 million years from deep-tow magnetic anomaly profiles across the Central Indian Ridge

International audienceHigh-resolution records of the geomagnetic field intensity over the last 4 Myr provided by paleomagnetic analyses of marine sediments have shown the occurrence of short-lived low field intensity features associated with excursions or short polarity intervals. In order to evaluate the ability of marine magnetic anomalies to record the same geomagnetic events, we have collected six deep-tow (-500 m above the seafloor) and several sea surface magnetic anomaly profiles from the Central Indian Ridge across the Brunhes, Matuyama, and Gauss chrons (i.e., from the ridge axis to anomaly 2A). After removal of topography, latitude, and azimuth effects, we converted distances into time sequences using well-dated polarity reversal anomalies as tie points. We calculated the average signal to test the robustness of the short-wavelength anomalies. The resulting stacked profile is very similar to stacked sea surface and downward continued profiles from the Central Indian Ridge, the East Pacific Rise, and the Pacific-Antarctic Ridge. Our results suggest that in addition to polarity reversals, to previously suggested geomagnetic events (subchrons or excursions) within the Brunhes and Matuyama chrons. A new small-scale magnetic anomaly, likely generated by several closely spaced geomagnetic field intensity variations represent the major contributor to the detailed shape of recent marine magnetic anomalies in investigated areas. We observe a dense succession of microanomalies that are correlated excursions (Ontong Java 1 and 2, and Gilsa), is found after the Olduvai chron. The near-bottom results support the existence of three geo-magnetic features between the Gauss-Matuyama boundary and Olduvai. They also suggest three geomagnetic events during the C2A. I n subchron within the Gauss chron. This study emphasizes the potential of deep-tow magnetic surveys in detecting fluctuations in geo-magnetic field intensity and, in particular, short-lived excursions, a poorly constrained part of the geomagnetic field temporal variation spectrum

Contribution à l’étude expérimentale de la transition laminaire-turbulent dans la couche limite au voisinage d’une carène

A contribution to the experimental investigation of laminar-to-turbulent transition in the boundary layer in the vicinity of a hull. Study of the variation of the coefficient of resistance for smooth hulls of different shapes with towing speed. Analysis of the transition from laminar to established turbulent flow.Le remorquage de carènes à très faibles vitesses permet à un régime franchement laminaire de s'établir dans la couche limite. Pour des vitesses plus grandes l'apparition de la transition se traduit par des irrégularités dans la détermination du coefficient de résistance liées au caractère instable de ce phénomène. L'étude détaillée et systématique des courbes du coefficient de résistance totale pour des carènes lisses de formes variées a permis d'analyser les conditions du changement de régime et de préciser l'apparition de l'écoulement turbulent stable.Ravilly J. Contribution à l’étude expérimentale de la transition laminaire-turbulent dans la couche limite au voisinage d’une carène. In: Les instabilités en hydraulique et en mécanique des fluides. Compte rendu des huitièmes journées de l'hydraulique; Lille, 8-10 juin 1964. Tome 1, 1965

ETUDE RHEOLOGIQUE D'UNE PATE CHARGEE EN PARTICULES METALLIQUES ET DESTINEE A L'INJECTION

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