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Choice and Consequence

Discussion in 'My Optimal Journal' started by crix, Aug 14, 2019.

  1. crix

    crix New Member

    Might get to myself later, but first I'll give a progress report for my honeybee colony. (The colony is a great way to stay connected to nature; also can serve as a canary of sorts).

    I currently give the entire colony photobiomodulation once per week (670nm + 830nm, see <https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0166531>).

    Also have made a DIY magnetico for the hive (made out of about 100 ceramic block magnets cut into thick books).

    Results so far are good! > ~50 lbs of honey.

    The colony started small (size = 5 frames) on June 6, but already had doubled to about 12 frames and was ready to swarm by June 26 (!). All this with no feeding of the colony!
     
  2. crix

    crix New Member

    Ayalon, I, Barros Marangoni, LFB, Benichou, JIC, Avisar, D, Levy, O. Red Sea corals under Artificial Light Pollution at Night (ALAN) undergo oxidative stress and photosynthetic impairment. Glob Change Biol. 2019; 00: 1– 14. https://doi.org/10.1111/gcb.14795

    <https://onlinelibrary.wiley.com/doi/full/10.1111/gcb.14795?campaign=wolearlyview>

    "Coral reefs represent the most diverse marine ecosystem on the planet, yet they are undergoing an unprecedented decline due to a combination of increasing global and local stressors. Despite the wealth of research investigating these stressors, Artificial Light Pollution at Night (ALAN) or “ecological light pollution” represents an emerging threat that has received little attention in the context of coral reefs, despite the potential of disrupting the chronobiology, physiology, behavior, and other biological processes of coral reef organisms. Scleractinian corals, the framework builders of coral reefs, depend on lunar illumination cues to synchronize their biological rhythms such as behavior, reproduction and physiology. While, light pollution (POL) may mask and lead de‐synchronization of these biological rhythms process. To reveal if ALAN impacts coral physiology, we have studied two coral species, Acropora eurystoma and Pocillopora damicornis, from the Gulf of Eilat/Aqaba, Red Sea, which is undergoing urban development that has led to severe POL at night. Our two experimental design data revealed that corals exposed to ALAN face an oxidative stress condition, show lower photosynthesis performances measured by electron transport rate (ETR), as well as changes in chlorophyll and algae density parameters. Testing different lights such as Blue LED and White LED spectrum showed more extreme impact in comparison to Yellow LEDs on coral physiology. The finding of this work sheds light on the emerging threat of POL and the impacts on the biology and ecology of Scleractinian corals, and will help to formulate specific management implementations to mitigate its potentially harmful impacts."
     
    JanSz likes this.
  3. crix

    crix New Member

    Dakhiya, Yuri, and Rachel M. Green. "Thermal imaging as a non‐invasive technique for analyzing circadian rhythms in plants." New Phytologist (2019). https://doi.org/10.1111/nph.16124

    Abstract:
    • Endogenous (˜24 circadian) rhythms control an enormously diverse range of processes in plants and are, increasingly, the target of studies aimed at understanding plant performance. Although in the previous few decades most plant circadian research has focused on Arabidopsis, there is a pressing need for low‐cost, high‐throughput tools for analyzing rhythms in a wider variety of species. The present contribution investigates using circadian temperature oscillations as a novel marker for assaying plant circadian rhythms.
    • A thermal imaging platform was set up to measure diel and circadian rhythms in different plant species, in wild‐type and circadian mutant plants, and in leaves and flowers. Results from the thermal imaging technique were compared with those from other established circadian assay techniques.
    • All of the dicot and monocot species examined showed robust circadian rhythms of leaf surface temperature; the effects of circadian mutations on thermocycles were similar to those reported using other techniques. In Petunia × atkinsiana plants circadian oscillations were observed in both leaves and flowers.
    • Thermal imaging is an extremely useful technique for analyzing circadian rhythms in plants. It is predicted that the ability to make very high temporal resolution measurements may facilitate the discovery of novel aspects of circadian control.
    <https://nph.onlinelibrary.wiley.com/doi/abs/10.1111/nph.16124?campaign=wolearlyview>
     
    Marko Pollo and JanSz like this.
  4. crix

    crix New Member

    Sicard, A. (2019), How bright is gold: is there a photosynthetic advantage to the golden angle?. New Phytol. doi:10.1111/nph.16183

    Abstract: "It is fascinating to observe that many organisms are built according to self‐organized processes obeying strict mathematical rules. These mechanisms most often reflect repeated and regular production of ‘developmental units or patterns’, whose positions are strictly defined by precise geometrical parameters. Such observations are particularly intriguing because they imply that molecular interactions are able to measure, define and maintain this ‘geometrical design’ over time; but also it raises the question of why evolution has selected these specific mathematical rules. The arrangement of leaves around the stem is one of the most prominent examples of such periodic, self‐organized processes in plants (Jean, 1997). Leaves are initiated from a continuously growing, dome‐shaped structure called the shoot apical meristem (SAM). Their initiation as the SAM grows is tightly controlled leading to a regular arrangement whose pattern, named phyllotaxy, will depend on the value of the divergent angle separating consecutive leaves. Yet, it is still unclear why some phyllotatic patterns tend to be more common than others. In a recent New Phytologist article, Strauss et al. (2019, doi: 10.1111/nph.16040) used an elegant computational approach to test how the leaf divergent angle influences the ability of plants to capture sunlight. This work represents the most thorough analysis of whether the most common angles constitute the optimal solution to capture light and maximize photosynthesis. It highlights the fact that phenotypic evolution cannot always simply be explained by the fitness advantage of new characters but may also depend on the developmental context in which they evolved (Uller et al., 2018)"
     
    JanSz likes this.
  5. crix

    crix New Member

    Strauss, S. , Lempe, J. , Prusinkiewicz, P. , Tsiantis, M. and Smith, R. S. (2019), Phyllotaxis: is the golden angle optimal for light capture?. New Phytol. doi:10.1111/nph.16040

    Summary:
    • Phyllotactic patterns are some of the most conspicuous in nature. To create these patterns plants must control the divergence angle between the appearance of successive organs, sometimes to within a fraction of a degree. The most common angle is the Fibonacci or golden angle, and its prevalence has led to the hypothesis that it has been selected by evolution as optimal for plants with respect to some fitness benefits, such as light capture.
    • We explore arguments for and against this idea with computer models. We have used both idealized and scanned leaves from Arabidopsis thaliana and Cardamine hirsuta to measure the overlapping leaf area of simulated plants after varying parameters such as leaf shape, incident light angles, and other leaf traits.
    • We find that other angles generated by Fibonacci‐like series found in nature are equally optimal for light capture, and therefore should be under similar evolutionary pressure.
    • Our findings suggest that the iterative mechanism for organ positioning itself is a more likely target for evolutionary pressure, rather than a specific divergence angle, and our model demonstrates that the heteroblastic progression of leaf shape in A. thaliana can provide a potential fitness benefit via light capture.
     
  6. crix

    crix New Member

    Attached Files:

    drezy likes this.
  7. crix

    crix New Member

    A good book for learning about the methods that have allowed scientists to study light in biology.

    Spectrophotometry & Spectrofluorimetry: A Practical Approach. D. A. Harris (Editor), C. L. Bashford (Editor). Oxford University Press (1987).

    https://www.amazon.com/Spectrophoto...rimetry+harris+bashford&qid=1572914394&sr=8-1

    From the introduction: "All biochemicals absorb energy from at least one region of the spectrum of electromagnetic radiation. The energies at which absorption occur depend on the available electronic, vibrational, and rotational energy level of the molecule."
     
    Linz likes this.
  8. crix

    crix New Member

    https://www.pnas.org/content/116/45/22413?etoc=

    News Feature: Quantum effects enter the macroworld. Stephen Ornes. PNAS. November 5, 2019 116 (45) 22413-22417; https://doi.org/10.1073/pnas.1917212116

    "University of Oxford physicist Vlatko Vedral, who developed one of the proposals, sees two main challenges: controlling ways the system might collapse into a classical state and differentiating between gravitational and electromagnetic effects. 'I believe this is not an insurmountable problem,' says Vedral."
     
    Last edited: Nov 6, 2019
  9. crix

    crix New Member

    Another good book for the mitochondriac: The Galileo Affair: A Documentary History.

    From the text:

    "Who wants to fix a limit for the human mind? Who wants to assert that everything which is knowable in the world is already known?"

    "Nature is inexorable and immutable; she never transgresses the laws imposed upon her, or cares a whit whether her abstruse reasons and methods of operation are understandable to men."

    https://www.amazon.com/Galileo-Cali...documents+galileo&qid=1575900368&sr=8-1-fkmr1
     
    Last edited: Dec 9, 2019 at 3:44 PM

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