4,535 research outputs found
A double-blind, placebo-controlled study evaluating the effects of caffeine and L-theanine both alone and in combination on cerebral blood flow, cognition and mood
No full textRationale -Evidence suggests interactive effects of the tea components caffeine and L-theanine on behaviour, yet no data exists exploring the impact of the two on cerebral blood flow (CBF).
Objectives - The current placebo-controlled, double-blind, counterbalanced, crossover study examined the effects of caffeine and L-theanine on CBF and extended previous cognitive and mood findings by using lower doses than previous studies of a similar methodology, which more closely reflect the ratios present in tea.
Methods - Twelve habitual consumers and 12 non-habitual consumers of caffeine each received 75 mg caffeine, 50 mg L-theanine, 75 mg caffeine plus 50 mg L-theanine, and placebo in a counterbalanced order across four separate visits. CBF was measured via near-infrared spectroscopy with cognition and mood assessed at baseline and 30 min post-dose. Salivary caffeine and peripheral haemodynamics were co-monitored.
Results - Caffeine reduced oxygenated haemoglobin (oxy-Hb), increased deoxygenated haemoglobin (deoxy-Hb), improved performance on attention tasks and increased overall mood ratings. Increases in deoxy-Hb following caffeine were more pronounced in non-consumers. Some evidence for increased deoxy-Hb remained when caffeine was combined with L-theanine, but this effect was attenuated and the effects of caffeine on oxy-Hb, cognition and mood were eradicated.
Conclusions - Combining L-theanine with caffeine, at levels and ratios equivalent to one to two cups of tea, eliminated the vasoconstrictive effect and behavioural effects of caffeine. This supports previous findings of an interaction between these substances, despite a lack of effects of L-theanine in isolation. However, at the levels tested here, this did not lead to a positive impact on behaviour
An essay on ridicule...
No full textAlso attributed by some to William Whitehead.A response to John Brown's Essays on the characteristics.Written by Allan Ramsay; cf. D. Eddy, A bibliography of John Brown, no. 106.Mode of access: Internet
The tea-table miscellany: : a collection of choice songs, Scots and English. : In two volumes. /
No full text"Explanation of the Scots words": [8] p. at end of v. 2.Comprises four volumes first published in 1724, 1725, 1727, and 1732; it is doubtful whether Ramsay collected or edited the fourth volume. Cf. NUC pre-1956."Containing old Scottish songs, English songs, songs by Ramsay and various contemporaries, and rereadings of Scots songs by Ramsay"--Cambridge history of Engl. lit., v. 9, p. 619.Mode of access: Internet
Consumption of cocoa flavanols results in acute improvements in mood and cognitive performance during sustained mental effort
No full textCocoa flavanols (CF) positively influence physiological processes in ways that suggest their consumption may improve aspects of cognitive function. This study investigated the acute cognitive and subjective effects of CF consumption during sustained mental demand. In this randomized, controlled, double-blinded, balanced, three period crossover trial 30 healthy adults consumed drinks containing 520 mg, 994 mg CF and a matched control, with a three-day washout between drinks. Assessments included the state anxiety inventory and repeated 10-min cycles of a Cognitive Demand Battery comprising of two serial subtraction tasks (Serial Threes and Serial Sevens), a Rapid Visual Information Processing (RVIP) task and a mental fatigue scale, over the course of 1 h. Consumption of both 520 mg and 994 mg CF significantly improved Serial Threes performance. The 994 mg CF beverage significantly speeded RVIP responses but also resulted in more errors during Serial Sevens. Increases in self-reported mental fatigue were significantly attenuated by the consumption of the 520 mg CF beverage only. This is the first report of acute cognitive improvements following CF consumption in healthy adults. While the mechanisms underlying the effects are unknown they may be related to known effects of CF on endothelial function and blood flow
The investigator. [electronic resource] : Containing the following tracts: I. On ridicule. II. On Elizabeth Canning. III. On naturalization. IV. On taste.
No full textAnonymous. By Allan Ramsay.Sometimes formerly also attributed to William Whitehead.Each tract has a separate titlepage, pagination and register.The first bears the imprint: printed for A. Millar, 1753; the second: printed for T. Seddon, 1753; the third and fourth are of the second edition: London: printed in the year 1762.All four tracts are now attrib. to Ramsay - cf. Smart, A.: 'The life and art of A. R.', 1952. H & L supp. concursElectronic reproduction.English Short Title Catalog,Reproduction of original from British Library
Age of the "Modelo" in Haskell Canyon, Easternmost Ventura Basin, California
No full textAn invertebrate fauna from the "Modelo" formation in Haskell Canyon, easternmost portion of the Ventura Basin California is listed and discussed. An Upper Miocene age, Neroly stage, is assigned to the fauna on the basis of Astrodapsis cf. tumidus, Astrodapsis of. whitneyi, Pecten
(Lyropecten) crassicardo, Turritella carrisaensis, Pecten (Aequipecten) discus, and Ostrea titan s.s. The Haskell Canyon fauna is correlated with the Santa Margarita s.s. and the Neroly formation of the San Pablo Group, and is shown to be older than the Jacalitos and the Elmere Canyon
faunas. A new species of Anadara is described
Map showing the approximate areal extent of the "Modelo" Formation in the Haskell Canyon-Dry Canyon area: Supplement 1 from "Age of the "Modelo" in Haskell Canyon, easternmost Ventura Basin, California" (Thesis)
No full textAn invertebrate fauna from the "Modelo" formation in Haskell Canyon, easternmost portion of the Ventura Basin California is listed and discussed. An Upper Miocene age, Neroly stage, is assigned to the fauna on the basis of Astrodapsis cf. tumidus, Astrodapsis of. whitneyi, Pecten (Lyropecten) crassicardo, Turritella carrisaensis, Pecten (Aequipecten) discus, and Ostrea titan s.s. The Haskell Canyon fauna is correlated with the Santa Margarita s.s. and the Neroly formation of the San Pablo Group, and is shown to be older than the Jacalitos and the Elmere Canyon faunas. A new species of Anadara is described
Effects of blackcurrant juice on pre-frontal cortical haemodynamics and cognition in healthy young adults
No full text\ua9 2025 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.Background: Evidence from randomised controlled trials demonstrates the modulatory effects of polyphenol consumption on the vascular system including improvements to cortical blood flow (CBF), microvascular blood flow, and large artery plasticity. Polyphenol-rich blackcurrants have been shown to inhibit monoamine oxidase, modulate brainwave spectral activity and modulate peripheral blood flow. This study assessed whether blackcurrant consumption can modulate blood flow in the shallow pre-frontal cortex, as measured using near infrared spectroscopy, during rest and under cognitive demand. Methods: A randomised double blind, placebo-controlled balanced cross over design was used to assess the efficacy of a cold pressed blackcurrant juice drink (Blackadder cultivar, Neuroberry, Plant and Food Research Ltd.) standardised at 500 mg of total polyphenols upon attention and working memory and prefrontal cortical haemodynamics at rest and during cognitive load in 20 healthy young adults aged 18–35 years, following a 60-minute absorption period. Results: Consumption of the Blackadder juice extract resulted in significant acute modulations of pre-frontal cortex haemodynamics during resting absorption and cognitive task performance as indicated by a decrease in deoxygenated haemoglobin [F(1,19) = 5.70, p = 0.027] and an increase in left hemisphere oxygenated haemoglobin during task performance [F(1.88,33.83) = 7.70, p = 0.002]. No effects on cognition were observed in this sample of healthy young adults. Conclusion: Results from this trial outline the ability of a blackcurrant juice extract to increase cerebral blood flow during cognitive demand in healthy young adults. The effects of the juice extract in addition to other types of blackcurrant extracts upon acute and chronic brain function and blood flow deserve further investigation. Trial registration:
The monk and miller's wife [electronic resource] : or, a' parties pleas'd: an unco tale. By Allan Ramsay.
No full textThe imprint follows the drop-head title.Also issued as part of 'Poetry; original and selected', vol. 1 (2nd issue), Glasgow, [1796].Not in Martin but cf. 399Electronic reproduction.English Short Title Catalog,Reproduction of original from Harvard University Houghton Library
The influence of fiber-matrix adhesion on the linear viscoelastic creep behavior of CF/PPS composites
No full textThe influence of fiber-matrix adhesion on the linear viscoelastic creep behavior of as received and surface modified carbon fiber (AR-CF and SM-CF, respectively) reinforced polyphenylene sulfide (PPS) composite materials was investigated. Short-term tensile creep tests were performed on ±45° specimens under four different isothermal condition; 70, 80, 90 and 100°C. As a preliminary step to obtain the time-temperature master curve, as well as to characterize the changes in matrix dominated properties over storage time, physical aging effects were evaluated on both systems using the short-term test method established by Struik. The results showed that the surface treatment carried out in the SM-CF improved fiber-matrix adhesion, enhancing the mechanical performance of CF/PPS composites but with minor effects on the creep response. Increasing retardation times with physical aging was observed in all test conditions. Compared to temperature effects, physical aging showed to have a small contribution on the creep behavior of CF/PPS composites.Aerospace Structures & MaterialsAerospace Engineerin
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