Although many studies using the fish photosensitive cells focus on circadian photopigments and the photic input pathway14,15,16,17,18,19,20,21,22,23,24,25,26, the specificity and generality of the photic gene regulation mechanism in lower vertebrates remains unclear. This is partly due to the high differentiation of systems within a single species. For example, even among the zebrafish photosensitive clock cell lines, the zPer2 gene is induced by blue Vintage Edison Bulbbut not red light in Z3 cells15, while it is induced by both blue and red light in PAC-2 cells25. Another reason for the lack of clarity may be the concentration of studies on zebrafish cells and the lack of a model cell line that originates from different species. In particular, the teleost species have a diverging repertoire of circadian clock genes due to lineage-specific gene duplications and differential gene deletions27. Therefore, we considered the search for another suitable fish cell line important for comparative analyses of the photoresponses and clock mechanisms across species.

Figure 16: Various conformations identified for VVD: Cluster 1(red) and 3D72_A(blue) Cluster 13(magenta), 3D72_B(ice blue) and 3RH8(green).
Figure 16
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Another intriguing observation of clustering analysis is that in clusters 1 through 10, the Fα and Eα helices, which cradle the FAD cofactor, remain in an extremely similar orientation, leaving a narrow space in between (Fig. 6A and B). However, in clusters 11 through 15, both Fα and Eα helices display obvious deviations among these structures, creating more space probably responding to the photo-activation of FAD.

Both Pro42 and Cys71(residue number 6 and 35 in the current study, respectively) are key residues projecting the N-terminus into different conformations24,31. Correspondingly, both RRS6 and RRS35 simulations showed significant impact on VVD Light state dynamics (Fig. 17). In RRS6, the Light state distribution splits into two attraction basins. In RRS35, the Light state distribution shifts upward along Y-axis, farther away from crystallographic T8 Fluorescent Lampsstate conformation. The other two key residues 55 and 171(residue number 19 and 135 in the current study, respectively) for VVD dimerization process discussed in ref. 31 also have significant impact on Light state dynamics under constraint perturbation (Fig. 17). In RRS19, the Light state distribution shifts toward left hand side along X-axis, closer to crystallographic Dark state conformation. But in RRS135, the Light state distribution splits into two attraction basins, which are significantly separate from each other. For all four residues above, the cross-correlations are significantly enhanced in Light states, while the cross-correlations remains moderate similar to unperturbed Dark state (Fig. 18).

Light compensation points of biocrusts under two water conditions (SW and E-NRW) and different temperature gradients.
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For R/Pg (Fig. 3a), it exponentially declined with light intensity, but as temperature increased, the differences among biocrusts gradually decreased and became more similar, especially when light intensity was higher than 25 μmol m-2 s-1. At 3 μmol m-2 s-1, R/Pg of AC1 was lowest, followed by AC2, then LCs and MC. At 5 μmol m-2 s-1 of light intensiy, R/Pg of two ACs were still lowest, that of MC was highest; but under -2.5~5 °C, the order of two lichen crusts was LC1 < LC2, under 7.5~10 °C, LC2 < LC1. Under 10 μmol m-2 s-1 light, R/Pg of LC2 was highest from -2.5~7.5 °C, LC1 was second-highest from 2.5~7.5 °C, MC was second-highest at -2.5 °C. At 10 °C, the sequence was LC1 > LC2 > MC.
The ratios of dark respiration to gross photosynthesis (R/Pg) for biocrusts at different range of Led Tube intensity (3~400 μmol m-2 s-1) and temperature gradients (-2.5~10 °C) under SW and E-NRW.
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R, Pn, LCPs, Pg and R/Pg under E-NRW
R of all biocrusts under E-NRW also increased with temperature (Fig. 4), the sequence from high to low was MC > LC2 > LC1 > AC2 > AC1. For Pn and LCPs, both increased with temperature, but Pn (except LC1 was never detected) had no significant differences (P > 0.05) between temperature gradient of 2.5 °C. At the same temperature, LCP in AC1 was lowest, in turn followed by AC2, LC2 and MC (Fig. 2b). Under light intensity lower than LCPs, the time window of positive Pn and the increasing amplitude with decreasing temperature manifested in the order: AC1 > AC2 > LC2 (LC2 slightly above MC). But the order reversed under higher light intensity, the increasing amplitude with rising temperature was in the order of AC1 > AC2 > LC2 ≈ MC. The pattern of Pg was similar to that of SW except for LC1 (Fig. 4), Pg also increased with light intensity and temperature, and the increasing amplitude was also highest in ACs, and then in turn was LCs and MC (Fig. 4a). The magnitude under the same temperature and light intensity from highest to the lowest was MC, LC2, AC2, and AC1. When light intensities were higher than 25 μmol m-2 s-1, the warming of 2.5 °C in ACs also resulted in quite different Pg.

Light, as the necessary condition for the carbon fixation of cryptogams, is the driving energy of the earth’s temperature change. Either seasonal or diurnal carbon exchange at global scale influenced by temperature is actually driven by solar irradiation. Since photosynthesis of most plants mainly occurs in daytime with abundant sunlight, previous studies paid more attention to the effects of temperature and water rather than light5, 18, 47, thus the influence of light on carbon exchange of biocrusts is also poorly known.

NRW accumulation occurs in the period from nightfall to early morning, with variable temperature, Led Bulb Light intensity and NRW amount, and this is an ideal natural opportunity to study the interactions between biocrusts carbon exchange and water, temperature and light. Therefore in this study, we selected 4 types of biocrusts that are highly dominated by variant cryptogams and possess different carbon assimilation mechanisms, namely 2 cyanobacteria crusts (AC1 and AC2), 1 lichen crust with cyanobacteria as photobiont (LC1), the other with green algae as photobiont (LC2) and 1 moss crust (MC). In order to obtain intrinsic potentiality and adaptation patterns of biocrustal carbon exchange responding to temperature, light and water, various light intensities and temperature conditions that were similar to the nights with abundant NRW, as well as two moisture gradients of saturated water (SW) and equivalent NRW (E-NRW) were firstly designed. The respiration rate (R), net photosynthesis rate (Pn), gross photosynthesis (Pg), and light compensation points (LCPs) of different biocrusts were measured, and the pattern of CO2 exchange were synchronously analyzed by multivariate nonlinear regression. The ratios of respiration to gross photosynthesis (R/Pg), which could reflect the biological differences of various biocrust types utilizing water, were also explored. Then, by in situ mesocosm experiments, CO2 exchanges of all chosen biocrusts were analyzed in NRW abundant seasons, the crucial factors and the patterns of CO2 exchange were determined by structural equation models, and the influencing degrees were quantifiably perceived by path coefficients. Finally, the community changes of biocrusts under the background of global climate change were predicted, and the suggestions for subsequent relative studies were proposed.

A Year After Paris Attacks, Tour Managers Reflect On Security
A crew sets up for Icelandic band Kaleo's show at Crystal Ballroom in Portland, Ore. A year ago today, terrorists attacked six locations in Paris, killing 130 people. Most of them were shot during a rock concert at a venue called the Bataclan. The attacks led to heightened new-lights security throughout Europe, and they've also led to some changes in how rock bands tour. Will Hackney is packing gear into a van on a loading dock in Portland, Ore. He's the bass player and tour manager for the band . They've got four amps, a ton of guitars and keyboards — and, Hackney says, "a British guitar player who brings the biggest suitcase I've ever seen." Over the course of 30 days, the group will travel 8,000 miles and visit 22 cities in the U.S. and Canada. It is Hackney's job to get them there. Tour managers are responsible for virtually every aspect of planning and executing the trip, and almost anything can go wrong. But there are some things Hackney has never worried much about. "You know, in all my years of touring, security has not really been something I've ever had to think about," Hackney says. "It usually feels like a pretty safe bubble." For many, that bubble popped after the Paris attacks. Just a few days later, Robin Laananen was on tour in Belgium with the band Refused — and Bataclan was on everyone's mind. During a Refused show, she spotted members of the military inside the showroom behind their sound engineer. "That's hard to see — people that you love playing music up on stage and knowing that that's a possibility and that could be going through their heads," she says. "And then everyone's worried about everybody in that room. It's really hard." Among those killed at the Bataclan was Nick Alexander, one of the crew for , the band playing that night. Jim Runge was friends with Alexander. Runge toured with and worked shows at the Bataclan before last year's tragedy. He says the attack was the catalyst for some changes to industry practices. It's now more common to use spotters to keep an eye out for anything unusual in the crowd. "There is somebody on stage, whether it be the tour manager, production manager, stage manager — somebody who is in charge of calling the show," Runge says. But Runge freely admits there's only so much that can be done. "You can check bags to make sure people aren't carrying in bombs or explosives or guns — dangerous things," he says. "But — I hate to even say it — if someone is coming at your door with automatic weapons, other than having armed guys at the door, protecting the door, which none of us want, what can you do?" That sense of helplessness has had a lasting new-lights effect on the psyche of the touring community, says Chris Coyle, calling from the road while on tour with rock band in Malmo, Sweden. "I don't really know how to put it into words about how I felt about [Bataclan]," Coyle says. "It was immediate sorrow. Talking about it now gets me all choked up. We never thought about having to deal with guns or anything at shows." Although Coyle says he hasn't drastically changed the way he runs tours, he now finds himself in the job of spotter more often. "If I see anything, I will stop the show and I will get the boys out," he says. Back in Portland, Hackney is done packing the van. True to form, he has already shifted his attention to working out the logistics of his band's next stop. But before driving off, he takes a few moments to reflect on the one-year anniversary of the Bataclan attack. "The point of that attack was to make people scared to have live music and do things like this," he says. "And everybody that I know is not going to stop for that." He doesn't have time to stop. He's got 17 cities and 6000 miles to go.