64 research outputs found

    Discovery of new colonies by Sentinel2 reveals good and bad news for emperor

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    The distribution of emperor penguins is circumpolar, with 54 colony locations currently reported of which 50 are currently extant as of 2019. Here we report on eight newly discovered colonies and confirm the rediscovery of three breeding sites, only previously reported in the era before Very High Resolution satellite imagery was available, making a total of 61 breeding locations. This represents an increase of ~20% in the number of breeding sites, but, as most of the colonies appear to be small, they may only increase the total population by around 5–10%. The discoveries have been facilitated by the use of Sentinel2 satellite imagery, which has a higher resolution and more efficient search mechanism than the Landsat data previously used to search for colonies. The small size of these new colonies indicates that considerations of reproductive output in relation to metabolic rate during huddling is likely to be of interest. Some of the colonies exist in offshore habitats, something not previously reported for emperor penguins. Comparison with recent modelling results show that the geographic locations of all the newly found colonies are in areas likely to be highly vulnerable under business‐as‐usual greenhouse gas emissions scenarios, suggesting that population decreases for the species will be greater than previously thought

    Induction of Biogenic Magnetization and Redox Control by a Component of the Target of Rapamycin Complex 1 Signaling Pathway

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    Most organisms are simply diamagnetic, while magnetotactic bacteria and migratory animals are among organisms that exploit magnetism. Biogenic magnetization not only is of fundamental interest, but also has industrial potential. However, the key factor(s) that enable biogenic magnetization in coordination with other cellular functions and metabolism remain unknown. To address the requirements for induction and the application of synthetic bio-magnetism, we explored the creation of magnetism in a simple model organism. Cell magnetization was first observed by attraction towards a magnet when normally diamagnetic yeast Saccharomyces cerevisiae were grown with ferric citrate. The magnetization was further enhanced by genetic modification of iron homeostasis and introduction of ferritin. The acquired magnetizable properties enabled the cells to be attracted to a magnet, and be trapped by a magnetic column. Superconducting quantum interference device (SQUID) magnetometry confirmed and quantitatively characterized the acquired paramagnetism. Electron microscopy and energy-dispersive X-ray spectroscopy showed electron-dense iron-containing aggregates within the magnetized cells. Magnetization-based screening of gene knockouts identified Tco89p, a component of TORC1 (Target of rapamycin complex 1), as important for magnetization; loss of TCO89 and treatment with rapamycin reduced magnetization in a TCO89-dependent manner. The TCO89 expression level positively correlated with magnetization, enabling inducible magnetization. Several carbon metabolism genes were also shown to affect magnetization. Redox mediators indicated that TCO89 alters the intracellular redox to an oxidized state in a dose-dependent manner. Taken together, we demonstrated that synthetic induction of magnetization is possible and that the key factors are local redox control through carbon metabolism and iron supply

    Novel facultative Methylocella strains are active methane consumers at terrestrial natural gas seeps

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    Natural gas seeps contribute to global climate change by releasing substantial amounts of the potent greenhouse gas methane and other climate-active gases including ethane and propane to the atmosphere. However, methanotrophs, bacteria capable of utilising methane as the sole source of carbon and energy, play a significant role in reducing the emissions of methane from many environments. Methylocella-like facultative methanotrophs are a unique group of bacteria that grow on other components of natural gas (i.e. ethane and propane) in addition to methane but a little is known about the distribution and activity of Methylocella in the environment. The purposes of this study were to identify bacteria involved in cycling methane emitted from natural gas seeps and, most importantly, to investigate if Methylocella-like facultative methanotrophs were active utilisers of natural gas at seep sites

    Cognitive bearing of techno-advances in Kashmiri carpet designing

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    The design process in Kashmiri carpet weaving is a distributed process encompassing a number of actors and artifacts. These include a designer called naqash who creates the design on graphs, and a coder called talim-guru who encodes that design in a specific notation called talim which is deciphered and interpreted by the weavers to weave the design. The technological interventions over the years have influenced these artifacts considerably and triggered major changes in the practice, from heralding profound cognitive accomplishments in manually driven design process causing major alterations in the overall structure of the practice. The recent intervention is by the digital technology: on the one hand, it has brought precision and speedy processing in the design process, and on the other, it has eliminated some of the crucial actors from the practice. This paper, which forms part of a larger study on the situated and distributed cognitive process in Kashmiri carpet-weaving practice, describes the technological makeover of the design artifacts involved in this practice over the years and their resultant cognitive impact on the design process as well as on the practice

    Video Games as Learning Tools for Your Media Curriculum

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    In this session, participants will learn experientially about how to enhance a media curriculum with video games to raise reading comprehension levels, technical writing, problem solving, and critical analysis of games as medium. The participants will be presented with curriculum, connections to standards, and methods for collecting their own data to influence and support policy decisions

    N-acetylation of arylalkylmines (serotonin and tryptamine) in the crayfish brain.

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    1. The presence of N-acetyltransferase in the crayfish brain (Pacifastacus leniusculus) was investigated. The arylalkylamines tryptamine and 14C-serotonin, are acetylated by crayfish brain homogenates with the acetyl donors 3H-acetyl coenzyme A and N, S-diacetylcysteamine, respectively.2. Resolution of serotonin metabolites by thin layer chromatography (chloroform/methanol/glacial acetic acid, 93 + 7 + 1 and ethyl acetate) revealed only one radioactive product (N-acetylserotonin, Rf 0.31) after enzymatic reaction. For example, melatonin and 5-hydroxyindole acetic acid could not be detected.3. This was also confirmed by reversed phase high performance liquid chromatography indicating the absence of monoamine oxidase and hydroxyindole-O-methyltransferase activity under the experimental conditions used.4. Inhibitory studies with cystamine suggest the involvement of heat sensitive disulfide compounds in the regulation of crayfish brain-N-acetyltransferase.5. N-acetylation seems to be a major pathway in the metabolism of biogenic amines in the crayfish central nervous system

    CellTrace™ Far Red & CellTracker™ Deep Red

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    Long term monitoring of live cells in vitro or in vivo presents considerable challenges.  Fluorescent tracers are used as one of the most common methods.  However, fluorescent molecules usually are limited by cytotoxicity and/or lack of persistence within live cells over sufficient time periods. In this study, we evaluated our newly developed cell tracing/tracking reagents, CellTrac Far Red and CellTracker Deep Red, as novel red laser-excitable fluorescent dyes for flow cytometry and live cell imaging applications. These dyes cross the plasma membrane and covalently bind proteins inside cells, where the stable, well-retained fluorescent label offers a consistent, reliable fluorescent signal without affecting morphology or physiology and also exhibiting low cellular toxicity. CellTrace Far Red was demonstrated to be an excellent probe for cellular proliferation studies using flow cytometry, allowing measurement of up to eight generations of proliferating cells. CellTracker Deep Red was shown to be an excellent reagent for the study of cell movement, location and morphology by labeling and imaging live-cells with fluorescence microscopy. In addition, CellTracker Deep Red has excellent cell retention characteristics with bright fluorescence intensity even after 72 hours of cell staining, with signal retained after fixation, and can be multiplexed with other fluorescent dyes
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