Drag reduction by polyethylene glycol in the tail arterial bed of normotensive and hypertensive rats

This study was designed to evaluate the effect of drag reducer polymers (DRP) on arteries from normotensive (Wistar) and spontaneously hypertensive rats (SHR). Polyethylene glycol (PEG 4000 at 5000 ppm) was perfused in the tail arterial bed with (E+) and without endothelium (E-) from male, adult Wistar (N = 14) and SHR (N = 13) animals under basal conditions (constant flow at 2.5 mL/min). In these preparations, flow-pressure curves (1.5 to 10 mL/min) were constructed before and 1 h after PEG 4000 perfusion. Afterwards, the tail arterial bed was fixed and the internal diameters of the arteries were then measured by microscopy and drag reduction was assessed based on the values of wall shear stress (WSS) by computational simulation. In Wistar and SHR groups, perfusion of PEG 4000 significantly reduced pulsatile pressure (Wistar/E+: 17.5 ± 2.8; SHR/E+: 16.3 ± 2.7%), WSS (Wistar/E+: 36; SHR/E+: 40%) and the flow-pressure response. The E- reduced the effects of PEG 4000 on arteries from both groups, suggesting that endothelial damage decreased the effect of PEG 4000 as a DRP. Moreover, the effects of PEG 4000 were more pronounced in the tail arterial bed from SHR compared to Wistar rats. In conclusion, these data demonstrated for the first time that PEG 4000 was more effective in reducing the pressure-flow response as well as WSS in the tail arterial bed of hypertensive than of normotensive rats and these effects were amplified by, but not dependent on, endothelial integrity. Thus, these results show an additional mechanism of action of this polymer besides its mechanical effect through the release and/or bioavailability of endothelial factors.

Possible states in the flow around two circular cylinders in tandem with separations in the vicinity of the drag inversion spacing

The possible states in the flow around two identical circular cylinders in tandem arrangements are investigated for configurations in the vicinity of the drag inversion separation. By means of numerical simulations, the hysteresis in the transition between the shedding regimes is studied and the relationship between (three-dimensional) secondary instabilities and shedding regime determination is addressed. The differences observed in the behavior of two- and three-dimensional flows are analyzed, and the regions of bistable flow are delimited. Very good agreement is found between the proposed scenario and results available in the literature. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3420111]

The glass ceiling hypothesis - A comparative study of the United States, Sweden, and Australia

The general-care glass ceiling hypothesis states that not only is it more difficult for women than for men to be promoted up levels of authority hierarchies within workplaces but also that the obstacles women face relative to men become greater as they move rtp the hierarchy. Gender-based discrimination in promotions is not simply present across levels of hierarchy but is more intense at higher levels. Empirically, this implies that the relative rates of women being promoted to higher levels compared to men should decline with the level of the hierarchy. This article explores this hypothesis with data from three countries: the United States, Australia, and Sweden. The basic conclusion is that while there is strong evidence for a general gender gap in authority-the odds of women having authority are less than those of men-there is no evidence for systematic glass ceiling effects in the United States and only weak evidence for such effects in the other two countries.

Four cases of equine polysaccharide storage myopathy in the United Kingdom

This paper describes four cases of equine polysaccharide storage myopathy which were confirmed by histological examination of muscle biopsy specimens. The horses were of mixed breeding, with warmblood and thoroughbred dominating. They all had recurrent episodes of rhabdomyolysis, indicated by clinical signs and increased plasma levels of muscle enzymes. They were managed conservatively and have continued athletic careers despite their disease.

The awareness of chronic fatigue syndrome: A comparative study in Brazil and the United Kingdom

Objective: While in many Western affluent countries there is widespread awareness of chronic fatigue syndrome (CFS), also known as myalgic encephalomyelitis (ME), little is known about the awareness of CFS/ME in low- and middle-income countries. We compared the awareness of CFS in Brazil and the United Kingdom. Methods: Recognition and knowledge of CFS were assessed among 120 Brazilian specialist doctors in two major university hospitals using a typical case vignette of CFS. We also surveyed 3914 and 2435 consecutive attenders in Brazilian and British primary care clinics, respectively, concerning their awareness of CFS. Results: When given a typical case vignette of CFS, only 30.8% [95% confidence interval (CI), 22.7-39.9%] of Brazilian specialist doctors mentioned chronic fatigue or CFS as a possible diagnosis, a proportion substantially lower than that observed in Western affluent countries. Similarly, only 16.2% (95% CI, 15.1-17.4%) of Brazilian primary care attenders were aware of CFS, in contrast to 55.1% (95% CI, 53.1-57.1%) of their British counterparts (P <.001). This difference remained highly significant after controlling for patients` sociodemographic and socioeconomic characteristics (P <.001). Conclusions: The awareness of CFS was substantially lower in Brazil than the United Kingdom. The observed difference may influence patients` help-seeking behavior and both doctors` and patients` beliefs and attitudes in relation to fatigue-related syndromes. Attempts to promote the awareness of CFS should be considered in Brazil, but careful plans are required to ensure the delivery of sound evidence-based information. (c) 2008 Elsevier Inc. All rights reserved.

Developing corporate image in higher education sector: a case study of University of East Anglia Norwich, United Kingdom’ [de] Muhammad Amjad, Muhammad Moazam Fraz [recensão crítica]

Recensão crítica do livro "AMJAD, Muhammad; FRAZ, Muhammad Moazam - Developing corporate image in higher education sector: a case study of University of East Anglia Norwich, United Kingdom. Lisboa: LAP LAMBERT Academic Publishing, 2012”.

Internationalization process of Science4you to the United Kingdom

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

Internationalization strategy of Shoes Closet to the United Kingdom

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

Adult learning and education policies in Germany, Portugal and Sweden: An analysis of national reports to CONFINTEA VI

The chapter presents a theoretical proposal of three analytical models of Adult Learning and Education (ALE) policies. Some analytical categories and the corresponding dimensions are organised according to the ALE rationale which is typical of each social policy model. Historical, cultural and educational features are mentioned in connexion with the different policy models and its interpretative capacity to making sense of policies and practices implemented in Germany, Portugal and Sweden. !e analysis includes the states of the art and the official representations of ALE produced by the respective national authorities through national reports which were presented to CONFINTEA VI (2009).