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The impact of fruit flavonoids on memory and cognition
There is intense interest in the studies related to the potential of phytochemical-rich foods to prevent age-related neurodegeneration and cognitive decline. Recent evidence has indicated that a group of plant-derived compounds known as flavonoids may exert particularly powerful actions on mammalian cognition and may reverse age-related declines in memory and learning. In particular, evidence suggests that foods rich in three specific flavonoid sub-groups, the flavanols, anthocyanins and/or flavanones, possess the greatest potential to act on the cognitive processes. This review will highlight the evidence for the actions of such flavonoids, found most commonly in fruits, such as apples, berries and citrus, on cognitive behaviour and the underlying cellular architecture. Although the precise mechanisms by which these flavonoids act within the brain remain unresolved, the present review focuses on their ability to protect vulnerable neurons and enhance the function of existing neuronal structures, two processes known to be influenced by flavonoids and also known to underpin neuro-cognitive function. Most notably, we discuss their selective interactions with protein kinase and lipid kinase signalling cascades (i.e. phosphoinositide-3 kinase/Akt and mitogen-activated protein kinase pathways), which regulate transcription factors and gene expression involved in both synaptic plasticity and cerebrovascular blood flow. Overall, the review attempts to provide an initial insight into the potential impact of regular flavonoid-rich fruit consumption on normal or abnormal deteriorations in cognitive performance
Loyalty and longevity in audience listening: investigating experiences of attendance at a chamber music festival
There is currently much concern amongst arts organisations and their marketing departments that audiences for classical music are in decline, yet little research has so far investigated the experiences of long-term listeners for insight on audience development and retention. This paper presents a case study of the Music in the Round chamber music festival, conducted over a three year period which included the retirement of the host string quartet, the appointment of a new resident ensemble, and associated changes in audience attitudes and priorities. The interaction between individual listening and collective membership of an audience is discussed, and the potential considered for understanding classical concert-goers as âfansâ or âconsumersâ
Managing rapport in intercultural business interactions: a comparison of two Chinese-British welcome meetings
This paper explores the management of rapport in intercultural business interactions. It compares two Chinese-British business welcome meetings that were held by the same British company. Despite many similarities between the two meetings, both the British and the Chinese were very satisfied with the first meeting, while the Chinese were very annoyed by the second. This paper describes the similarities and differences between the two meetings, and explores why they were evaluated so differently. It argues that research into the management of relations in intercultural communication needs to use a broader analytic framework than is typical of intercultural discourse research, and that it needs to gather a wider range of data types
Re-establishing Justice as a Pillar of Ecological Economics Through Feminist
Ecological economics has long claimed distributive justice as a central tenet, yet discussions of equity and justice have received relatively little attention over the history of the field. While ecological economics has aspired to be transdisciplinary, its framing of justice is hardly pluralistic. Feminist perspectives and justice frameworks offer a structure for appraising the human condition that bridges social and ecological issues. Through a brief overview of the uptake of feminist perspectives in other social sciences, this paper outlines an initial justice-integration strategy for ecological economics by providing both a point of entry for readers to the vast and diverse field of feminist economic thought, as well as a context for the process of disciplinary evolution in social sciences. We also critique ecological economics' toleration of neoclassical mainstays such as individualism that run counter to justice goals. The paper concludes with a call for ecological economics practitioners and theorists to learn from other social sciences and elevate their attention to justice, to open possibilities for more dynamic, inter- disciplinary, community-oriented, and pluralistic analysis.This research was supported by the Social Sciences and Humanities Research Council of Canada SSHRC File #: 895-2013-1010 Project period: 01-April-14 to 31-Mar-2
A Robust Numerical Method for Integration of Point-Vortex Trajectories in Two Dimensions
The venerable 2D point-vortex model plays an important role as a simplified
version of many disparate physical systems, including superfluids,
Bose-Einstein condensates, certain plasma configurations, and inviscid
turbulence. This system is also a veritable mathematical playground, touching
upon many different disciplines from topology to dynamic systems theory.
Point-vortex dynamics are described by a relatively simple system of nonlinear
ODEs which can easily be integrated numerically using an appropriate adaptive
time stepping method. As the separation between a pair of vortices relative to
all other inter-vortex length scales decreases, however, the computational time
required diverges. Accuracy is usually the most discouraging casualty when
trying to account for such vortex motion, though the varying energy of this
ostensibly Hamiltonian system is a potentially more serious problem. We solve
these problems by a series of coordinate transformations: We first transform to
action-angle coordinates, which, to lowest order, treat the close pair as a
single vortex amongst all others with an internal degree of freedom. We next,
and most importantly, apply Lie transform perturbation theory to remove the
higher-order correction terms in succession. The overall transformation
drastically increases the numerical efficiency and ensures that the total
energy remains constant to high accuracy.Comment: 21 pages, 4 figure
Acute effects of Hibiscus sabdariffa calyces on postprandial blood pressure, vascular function, blood lipids, biomarkers of insulin resistance and inflammation in humans
The acute impact of Hibiscus sabdariffa calyces (HSC) extract on postprandial vascular function and other cardiometabolic risk factors have not been studied previously. This study investigated the acute impact of HSC extract consumption on blood pressure (BP), vascular function and other cardiometabolic risk markers. Twenty-five men with 1% to 10% cardiovascular disease (CVD) risk (determined by QRISK 2) were randomised to consume either 250 mL of the aqueous extract of HSC or water with breakfast in a randomised, controlled, single-blinded, 2-meal cross-over study (ClinicalTrials.gov, NTC02165553) with a two weeks washout period between study days. BP was measured at baseline and hourly for 4 h. Flow mediated dilatation (FMD) of the branchial artery was measured at baseline, 2 and 4 h post intervention drink consumption. Acute consumption of aqueous extract of HSC caused a significant increase in % FMD ( < 0.001), a non-significant decrease in systolic BP (SBP) and diastolic BP (DBP); non-significant increase in urinary and plasma nitric oxide (NOx) and reduced response of serum glucose, plasma insulin, serum triacylglycerol and C-reactive protein (CRP) levels; significant ( = 0.026) improvement in the area under systemic antioxidant response curve (0 to 2 h); no significant changes in arterial stiffness following the acute consumption of the extract of HSC. Gallic acid, 4-O-methylgallic acid, 3-O-methylgallic acid and hippuric acid reached a maximum plasma concentration at 1 to 2 h post consumption of the extract of HSC. The extract of HSC improved postprandial vascular function and may be a useful dietary strategy to reduce endothelial dysfunction and CVD risk, although this requires confirmation
Compact steep-spectrum sources from the S4 sample
We present the results of 5-GHz observations with the VLA A-array of a sample
of candidate Compact Steep Spectrum sources (CSSs) selected from the S4 survey.
We also estimate the symmetry parameters of high-luminosity CSSs selected from
different samples of radio sources, and compare these with the larger sources
of similar luminosity to understand their evolution and the consistency of the
CSSs with the unified scheme for radio galaxies and quasars. The majority of
CSSs are likely to be young sources advancing outwards through a dense
asymmetric environment. The radio properties of CSSs are found to be consistent
with the unified scheme, in which the axes of the quasars are observed close to
the line of sight, while radio galaxies are observed close to the plane of the
sky.Comment: accepted for publication in mnras; 8 pages, figure 1 with 21 images,
and two additional figures; 2 table
Radio Observations of the Black Hole Candidate GX 339-4
The black hole candidate GX 339-4 was first detected as a variable radio
source by Sood & Campbell-Wilson in May 1994 with the Molonglo Observatory
Synthesis Telescope (MOST). Since then, several observations have been obtained
with the Australian Telescope Compact Array (ATCA) in order to study the radio
behavior of this source in relation to its soft and hard X-ray activity. We
present new results of high resolution radio observations performed with the
ATCA in order to study the jet-like feature observed in GX 339-4 by Fender et
al (1997). From the ATCA lightcurve at 8640 MHz, we find evidence of quenched
radio emission from GX 339-4.Comment: To appear in Proc. 4th Compton Symposium, AIP pres
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