SciCombinator

Discover the most talked about and latest scientific content & concepts.

Concept: Red

279

Migraine headache is uniquely exacerbated by light. Using psychophysical assessments in patients with normal eyesight we found that green light exacerbates migraine headache significantly less than white, blue, amber or red lights. To delineate mechanisms, we used electroretinography and visual evoked potential recording in patients, and multi-unit recording of dura- and light-sensitive thalamic neurons in rats to show that green activates cone-driven retinal pathways to a lesser extent than white, blue and red; that thalamic neurons are most responsive to blue and least responsive to green; and that cortical responses to green are significantly smaller than those generated by blue, amber and red lights. These findings suggest that patients' experience with colour and migraine photophobia could originate in cone-driven retinal pathways, fine-tuned in relay thalamic neurons outside the main visual pathway, and preserved by the cortex. Additionally, the findings provide substrate for the soothing effects of green light.

Concepts: Migraine, Light, Green, Cerebral cortex, Brain, Red, Color, Retina

181

Evidence suggests that light and circadian rhythms profoundly influence the physiologic capacity with which an organism responds to stress. However, the ramifications of light spectrum on the course of critical illness remain to be determined. Here, we show that acute exposure to bright blue spectrum light reduces organ injury by comparison with bright red spectrum or ambient white fluorescent light in two murine models of sterile insult: warm liver ischemia/reperfusion (I/R) and unilateral renal I/R. Exposure to bright blue light before I/R reduced hepatocellular injury and necrosis and reduced acute kidney injury and necrosis. In both models, blue light reduced neutrophil influx, as evidenced by reduced myeloperoxidase (MPO) within each organ, and reduced the release of high-mobility group box 1 (HMGB1), a neutrophil chemotactant and key mediator in the pathogenesis of I/R injury. The protective mechanism appeared to involve an optic pathway and was mediated, in part, by a sympathetic (β3 adrenergic) pathway that functioned independent of significant alterations in melatonin or corticosterone concentrations to regulate neutrophil recruitment. These data suggest that modifying the spectrum of light may offer therapeutic utility in sterile forms of cellular injury.

Concepts: Biology, Circadian rhythm, Blue, Photoreceptor cell, Spectrum, Light, Red, Visible spectrum

172

A basic premise of the recently proffered color-in-context model is that the influence of color on psychological functioning varies as a function of the psychological context in which color is perceived. Some research has examined the appetitive and aversive implications of viewing the color red in romance- and achievement-relevant contexts, respectively, but in all existing empirical work approach and avoidance behavior has been studied in separate tasks and separate experiments. Research is needed to directly test whether red influences the same behavior differently depending entirely on psychological context.

Concepts: RGB color model, Visible spectrum, Green, Science, Primary color, Color, Red, Psychology

28

Vegetation phenology controls the seasonality of many ecosystem processes, as well as numerous biosphere-atmosphere feedbacks. Phenology is also highly sensitive to climate change and variability. Here we present a series of datasets, together consisting of almost 750 years of observations, characterizing vegetation phenology in diverse ecosystems across North America. Our data are derived from conventional, visible-wavelength, automated digital camera imagery collected through the PhenoCam network. For each archived image, we extracted RGB (red, green, blue) colour channel information, with means and other statistics calculated across a region-of-interest (ROI) delineating a specific vegetation type. From the high-frequency (typically, 30 min) imagery, we derived time series characterizing vegetation colour, including “canopy greenness”, processed to 1- and 3-day intervals. For ecosystems with one or more annual cycles of vegetation activity, we provide estimates, with uncertainties, for the start of the “greenness rising” and end of the “greenness falling” stages. The database can be used for phenological model validation and development, evaluation of satellite remote sensing data products, benchmarking earth system models, and studies of climate change impacts on terrestrial ecosystems.

Concepts: Climate, Red, Climate change, Phenology, Ecosystem, Biome, Remote sensing, Vegetation

28

Grouping behaviours (e.g. schooling, shoaling and swarming) are commonly explicated through adaptive hypotheses such as protection against predation, access to mates or improved foraging. However, the hypothesis that aggregation can result from manipulation by parasites to increase their transmission has never been demonstrated. We investigated this hypothesis using natural populations of two crustacean hosts (Artemia franciscana and Artemia parthenogenetica) infected with one cestode and two microsporidian parasites. We found that swarming propensity increased in cestode-infected hosts and that red colour intensity was higher in swarming compared with non-swarming infected hosts. These effects likely result in increased cestode transmission to its final avian host. Furthermore, we found that microsporidian-infected hosts had both increased swarming propensity and surfacing behaviour. Finally, we demonstrated using experimental infections that these concurrent manipulations result in increased spore transmission to new hosts. Hence, this study suggests that parasites can play a prominent role in host grouping behaviours.

Concepts: Parasites, Hypothesis, Red, Experiment, Brine shrimp, Transmission and infection of H5N1, Behavior

28

Based on 2,2':6',2'‘-terpyridine ligands (), five terpyridine derivatives, namely 4’-carbazol-9-yl-2,2':6',2'‘-terpyridine (), 4’-diphenylamino-2,2':6',2'‘-terpyridine (), 4’-bis(4-tert-butylphenyl)amino-2,2':6',2'‘-terpyridine (), 4’-[naphthalen-1-yl-(phenyl)amino]-2,2':6',2'‘-terpyridine (), 4’-[naphthalen-2-yl(phenyl)amino]-2,2':6',2'‘-terpyridine () and their corresponding Re(i) complexes (n = 1-6) have been synthesized and characterized by elemental analysis and (1)H NMR spectroscopy. The X-ray crystal structure of has also been obtained. The luminescence spectra of , obtained in CH(2)Cl(2) solution at room temperature, show strong dπ (Re) → π* (diimine) MLCT character (λ(max) ∼ 600 nm) and a small red shift relative to . This, confirmed by the study of the triplet energy levels of the ligands at low temperature (77 K rigid matrix), indicates that the introduction of electron-donating moieties on the terpyridine unit decreases the triplet levels of the ligands, leading to a reduction of the energy gap between d and π* orbitals. In the solid state, upon MLCT excitation, all the complexes show an even stronger emission and a blue spectral shift (λ(max) ∼ 550 nm) compared to those obtained in solution.

Concepts: Quasar, Red, Physical quantities, Light, Redshift, Astronomical spectroscopy, Solid, Spectroscopy

28

ETHNOPHARMACOLOGICAL RELEVANCE: Red edible bird’s nests are regarded as of higher beneficial value for health and hence fetch a higher price than the white ones. Their red colour remains a myth. AIM OF THE STUDY: To determine if white edible bird’s nests can turn red by vapours generated from sodium nitrite in acidic conditions and by vapours from ‘bird soil’. MATERIALS AND METHODS: White edible bird’s nests were exposed to vapours from sodium nitrite dissolved in 2% HCl or from ‘bird soil’ in hot and humid conditions. CONCLUSIONS: Vapours from sodium nitrite dissolved in 2% HCl or from ‘bird soil’ containing guano droppings from swiftlet houses were able to turn white edible bird’s nests red. The reddening agent in ‘bird soil’ was water-soluble and heat-stable. The red colour of edible bird’s nests is likely caused by the environmental factors in cave interiors and swiftlet houses.

Concepts: Guano, Manure, Primary color, Ammonia, Green, White, Color, Red

27

To fold or not to fold? It is shown that attached sugars play a defining role in the conformations adopted by a pair of novel SAA-derived foldamers in water and that these differences are reflected in the contrasting interactions of these glycofoldamers with various biological targets. C green, O red, N blue, H gray; green oval=mannose.

Concepts: Cyan, Primary color, Natural environment, Ecology, Life, Green, Red, Aristotle

26

No one knew how the tradition started, but on Christmas Day it was my job as charge nurse to come in early and make bacon butties for the staff. White sliced bread, oodles of butter and Daddies sauce - all the things you are not supposed to have, which taste all the more enjoyable for it. And tea strong enough to stand up a spoon in.

Concepts: Red, Sliced bread, Russia

26

The present investigation focuses on the textural properties, sensory attributes and color changes of beef frankfurter, beef ham and meat-free sausage produced by different levels of bleached tomato pomace. The texture and color profile were performed using an instrumental texture analyzer and colorimeter. The findings indicated that tomato pomace-added sausages had higher water holding capacity (WHC) compared to that of commercial samples. The frankfurters containing 5 and 7% (w/w) tomato pomace had the highest redness (a*), chroma (C*) and color differences (ΔE) values, while the meat-free sausages containing 7% (w/w) tomato pomace had significant (p<0.05) values for lightness (L*) and yellowness (b*). Furthermore, there were no significant (p>0.05) color differences between beef ham samples (with and without tomato pomace). A significant progression in the textural hardness and chewiness of systems containing tomato pomace was observed as well as higher sensory scores by panelists. According to sensorial evaluations, bleached tomato pomace improved the consumer acceptability and preference.

Concepts: Charcuterie, Bologna sausage, Meat, Red, Beef, Pork, Hot dog, Sausage