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    A new book shows how animals are already coping with climate change

    Hurricane Lizards and Plastic SquidThor HansonBasic Books, $28

    As a conservation biologist, Thor Hanson has seen firsthand the effects of climate change on plants and animals in the wild: the green macaws of Central America migrating along with their food sources, the brown bears of Alaska fattening up on early-ripening berry crops, the conifers of New England seeking refuge from vanishing habitats. And as an engaging author who has celebrated the wonders of nature in books about feathers, seeds, forests and bees (SN: 7/21/18, p. 28), he’s an ideal guide to a topic that might otherwise send readers down a well of despair.

    Hanson does not despair in his latest book, Hurricane Lizards and Plastic Squid. Though he outlines the many ways that global warming is changing life on our planet, his tone is not one of hand-wringing. Instead, Hanson invites the reader into the stories of particular people, places and creatures of all sorts. He draws these tales from his own experiences and those of other scientists, combining reporting with narrative tales of species that serve as examples of broader trends in the natural world.

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    A trip to La Selva Biological Station in Costa Rica, for example, has Hanson reliving the experience of tropical ecologist and climatologist Leslie Holdridge, who founded the research station in the 1950s and described, among other things, how climate creates different habitats, or life zones, as elevation increases. As Hanson sweats his way up a tropical mountainside so he can witness a shift in life zones, he notes, “I had to earn every foot of elevation gain the hard way.” I could almost feel the heat that he describes as “a steaming towel draped over my head.” His vivid descriptions bring home the reason why so many species have now been documented moving upslope to cooler climes.

    Hanson doesn’t waste much breath trying to convince doubters of the reality of climate change, instead showing by example after example how it is already playing out. The book moves quickly from the basic science of climate change to the challenges and opportunities that species face — from shifts in seasonal timing to ocean acidification — and the ways that species are responding.

    As Hanson notes, the acronym MAD, for “move, adapt or die,” is often used to describe species’ options for responding. But that pithy phrase doesn’t capture the complexity of the situation. For instance, one of his titular characters, a lizard slammed by back-to-back Caribbean hurricanes in 2017, illustrates a different response. Instead of individual lizards adjusting, or adapting, to increasingly stormy conditions, the species evolved through natural selection. Biologists monitoring the lizards on two islands noticed that after the hurricanes, the lizard populations had longer front legs, shorter back legs and grippier toe pads on average than they had before. An experiment with a leaf blower showed that these traits help the lizards cling to branches better — survival of the fittest in action.

    In the end, the outcomes for species will probably be as varied as their circumstances. Some organisms have already moved, adapted or died as a result of the warming, and many more will face challenges from changes that are yet to come. But Hanson hasn’t given up hope. When it comes to preventing the worst-case scenarios, he quotes ecologist Gordon Orians, who is in the seventh decade of a career witnessing environmental change. When asked what a concerned citizen should do to combat climate change, he responded succinctly: “Everything you can.” And as Hanson points out, this is exactly how plants and animals are responding to climate change: by doing everything they can. The challenge feels overwhelming, and as a single concerned citizen, much feels out of my hands. Yet Hanson’s words did inspire me to take a cue from the rest of the species on this warming world to do what I can.

    Buy Hurricane Lizards and Plastic Squid from Bookshop.org. Science News is a Bookshop.org affiliate and will earn a commission on purchases made from links in this article. More

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    Development of an artificial vision device capable of mimicking human optical illusions

    NIMS has developed an ionic artificial vision device capable of increasing the edge contrast between the darker and lighter areas of an mage in a manner similar to that of human vision. This first-ever synthetic mimicry of human optical illusions was achieved using ionic migration and interaction within solids. It may be possible to use the device to develop compact, energy-efficient visual sensing and image processing hardware systems capable of processing analog signals.
    Numerous artificial intelligence (AI) systems developers have recently shown a great deal of interest in research on various sensors and analog information processing systems inspired by human sensory mechanisms. Most AI systems on which research is being conducted require sophisticated software/programs and complex circuit configurations, including custom-designed processing modules equipped with arithmetic circuits and memory. These systems have disadvantages, however, in that they are large and consume a great deal of power.
    The NIMS research team recently developed an ionic artificial vision device composed of an array of mixed conductor channels placed on a solid electrolyte at regular intervals. This device simulates the way in which human retinal neurons (i.e., photoreceptors, horizontal cells and bipolar cells) process visual signals by responding to input voltage pulses (equivalent to electrical signals from photoreceptors). This causes ions within the solid electrolyte (equivalent to a horizontal cell) to migrate across the mixed conductor channels, which then changes the output channel current (equivalent to a bipolar cell response). By employing such steps, the device, independent of software, was able to process input image signals and produce an output image with increased edge contrast between darker and lighter areas in a manner similar to the way in which the human visual system can increase edge contrast between different colors and shapes by means of visual lateral inhibition.
    The human eye produces various optical illusions associated with tilt angle, size, color and movement, in addition to darkness/lightness, and this process is believed to play a crucial role in the visual identification of different objects. The ionic artificial vision device described here may potentially be used to reproduce these other types of optical illusions. The research team involved hopes to develop visual sensing systems capable of performing human retinal functions by integrating the subject device with other components, including photoreceptor circuits.
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    Materials provided by National Institute for Materials Science, Japan. Note: Content may be edited for style and length. More

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    Corals may store a surprising amount of microplastics in their skeletons

    A surprising amount of plastic pollution in the ocean may wind up in a previously overlooked spot: the skeletons of living corals. 

    Up to about 20,000 metric tons of tiny fragments called microplastics may be stored in coral skeletons worldwide every year, says ecologist Jessica Reichert of Justus Liebig University Giessen in Germany. That corresponds to nearly 3 percent of the microplastics estimated to be in the shallow, tropical waters where corals thrive.

    Corals have been observed eating or otherwise incorporating microplastics into their bodies (SNS: 3/18/15). But scientists don’t know how much of the debris reefs take up globally. So Reichert and colleagues exposed corals in the lab to microplastics to find out where the particles are stored inside corals and estimate how much is tucked away.

    Corals consumed some of the trash, or grew their skeletons over particles. After 18 months, most of the debris inside corals was in their skeletons rather than tissues, the researchers report October 28 in Global Change Biology. After counting the number of trapped particles, the researchers estimate that between nearly 6 billion and 7 quadrillion microplastic particles may be permanently stored in corals worldwide annually.

    Tiny plastic particles (black spots in this image of coral that has had its tissue removed) end up trapped in coral skeletons when corals grow over the fragments or ingest them.J. Reichert

    It’s the first time that a living microplastic “sink,” or long-term storage site, has been quantified, Reichert says.

    Scientists are learning how much microplastic is being introduced to the oceans. But researchers don’t know where it all ends up (SN: 6/6/19). Other known microplastic sinks, such as sea ice and seafloor sediments, need better quantification, and other sinks may not yet be known.

    Reefs are typically found near coasts where polluted waterways can drain to the sea, placing corals in potential microplastic hot spots.

    “We don’t know what consequences this [storage] might have for the coral organisms, [or for] reef stability and integrity,” Reichert says. It “might pose an additional threat to coral reefs worldwide.”  

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    'Magic wand' reveals a colorful nano-world

    Scientists have developed new materials for next-generation electronics so tiny that they are not only indistinguishable when closely packed, but they also don’t reflect enough light to show fine details, such as colors, with even the most powerful optical microscopes. Under an optical microscope, carbon nanotubes, for example, look grayish. The inability to distinguish fine details and differences between individual pieces of nanomaterials makes it hard for scientists to study their unique properties and discover ways to perfect them for industrial use.
    In a new report in Nature Communications, researchers from UC Riverside describe a revolutionary imaging technology that compresses lamp light into a nanometer-sized spot. It holds that light at the end of a silver nanowire like a Hogwarts student practicing the “Lumos” spell, and uses it to reveal previously invisible details, including colors.
    The advance, improving color-imaging resolution to an unprecedented 6 nanometer level, will help scientists see nanomaterials in enough detail to make them more useful in electronics and other applications.
    Ming Liu and Ruoxue Yan, associate professors in UC Riverside’s Marlan and Rosemary Bourns College of Engineering, developed this unique tool with a superfocusing technique developed by the team. The technique has been used in previous work to observe the vibration of molecular bonds at 1-nanometer spatial resolution without the need of any focusing lens.
    In the new report, Liu and Yan modified the tool to measure signals spanning the whole visible wavelength range, which can be used to render the color and depict the electronic band structures of the object instead of only molecule vibrations. The tool squeezes the light from a tungsten lamp into a silver nanowire with near-zero scattering or reflection, where light is carried by the oscillation wave of free electrons at the silver surface.
    The condensed light leaves the silver nanowire tip, which has a radius of just 5 nanometers, in a conical path, like the light beam from a flashlight. When the tip passes over an object, its influence on the beam shape and color is detected and recorded.
    “It is like using your thumb to control the water spray from a hose,” Liu said, “You know how to get the desired spraying pattern by changing the thumb position, and likewise, in the experiment, we read the light pattern to retrieve the details of the object blocking the 5 nm-sized light nozzle.”
    The light is then focused into a spectrometer, where it forms a tiny ring shape. By scanning the probe over an area and recording two spectra for each pixel, the researchers can formulate the absorption and scattering images with colors. The originally grayish carbon nanotubes receive their first color photograph, and an individual carbon nanotube now has the chance to exhibit its unique color.
    “The atomically smooth sharp-tip silver nanowire and its nearly scatterless optical coupling and focusing is critical for the imaging,” Yan said. “Otherwise there would be intense stray light in the background that ruins the whole effort. ”
    The researchers expect that the new technology can be an important tool to help the semiconductor industry make uniform nanomaterials with consistent properties for use in electronic devices. The new full-color nano-imaging technique could also be used to improve understanding of catalysis, quantum optics, and nanoelectronics.
    Liu, Yan, and Ma were joined in the research by Xuezhi Ma, a postdoctoral scholar at Temple University who worked on the project as part of his doctoral research at UCR Riverside. Researchers also included UCR students Qiushi Liu, Ning Yu, Da Xu, Sanggon Kim, Zebin Liu, Kaili Jiang, and professor Bryan Wong. The paper, titled “6 nm super-resolution optical transmission and scattering spectroscopic imaging of carbon nanotubes using a nanometer-scale white light source,” is available here.
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    Materials provided by University of California – Riverside. Original written by Holly Ober. Note: Content may be edited for style and length. More

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    How molecular clusters in the nucleus interact with chromosomes

    A cell stores all of its genetic material in its nucleus, in the form of chromosomes, but that’s not all that’s tucked away in there. The nucleus is also home to small bodies called nucleoli — clusters of proteins and RNA that help build ribosomes.
    Using computer simulations, MIT chemists have now discovered how these bodies interact with chromosomes in the nucleus, and how those interactions help the nucleoli exist as stable droplets within the nucleus.
    Their findings also suggest that chromatin-nuclear body interactions lead the genome to take on a gel-like structure, which helps to promote stable interactions between the genome and transcription machineries. These interactions help control gene expression.
    “This model has inspired us to think that the genome may have gel-like features that could help the system encode important contacts and help further translate those contacts into functional outputs,” says Bin Zhang, the Pfizer-Laubach Career Development Associate Professor of Chemistry at MIT, an associate member of the Broad Institute of Harvard and MIT, and the senior author of the study.
    MIT graduate student Yifeng Qi is the lead author of the paper, which appears today in Nature Communications.
    Modeling droplets
    Much of Zhang’s research focuses on modeling the three-dimensional structure of the genome and analyzing how that structure influences gene regulation. More

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    A new way to generate electricity from waste heat: Using an antiferromagnet for solid devices

    Forcing electrons to flow perpendicularly to a heat flow requires an external magnetic field – this is known as the Nernst effect. In a permanently magnetized material (a ferromagnet), an anomalous Nernst effect (ANE) exists that can generate electricity from heat even without a magnetic field. The anomalous Nernst effect scales with the magnetic moment of the ferromagnet. An antiferromagnet, with two compensating magnetic sublattices shows no external magnetic moment and no measurable external magnetic field and therefore should not exhibit any ANE. However, we have recently understood that by the new concept of topology can be applied to achieve large Nernst effects in magnets. In particular, we have learned that the quantity known as the Berry phase is related to the ANE and can greatly increase it. However, the ANE in antiferromagnets is still largely unexplored, in part because the ANE was not thought to exist. Remarkably, a joint research team from the Max Planck Institute for Chemical Physics of Solids in Dresden, Germany, together with collaborators at the Ohio State University and the University of Cincinnati, has found a large anomalous Nernst effect, larger than is known in almost all ferromagnets in YbMnBi2, an antiferromagnet.

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    A seemingly unattainable energy transition

    Researchers from Basel and Bochum have succeeded in addressing an apparently unattainable energy transition in an artificial atom using laser light. Making use of the so-called radiative Auger process, they were the first team to specifically excite it. In this process, an electron falls from a higher to a lower energy level and, as a result, emits its energy partly in the form of light and partly by transferring it to another electron. The artificial atoms are narrowly defined areas in semiconductors that could one day form the basis for quantum communication. The findings are described by the team from the University of Basel and Ruhr-Universität Bochum together with colleagues from Münster and Wroclaw in “Nature Communications,” published online on 12 November 2021.
    Electrons move between energy states
    Atoms consist of a nucleus and electrons that travel around the nucleus. These electrons can assume different energy levels. Electrons that are more tightly bound to the nucleus, i.e. closer to it, have a lower energy than electrons that are further away from the nucleus. However, the electrons can’t assume any arbitrary energy levels — only certain levels are possible.
    If an electron acquires energy, for example by absorbing a light particle, i.e. photon, it can be raised to a higher energy level. If an electron falls to a lower energy level, energy is released. This energy can be emitted in the form of a photon. But it can also be transferred to one of the other electrons; in this case, only some of the energy is released as light, the rest is absorbed by the other electron. This process is known as the radiative Auger process.
    Exciting a unique energy transition with two lasers
    By irradiating light particles, electrons can not only be lifted to a higher energy level; they can also be stimulated to give off energy by an incident light particle. The energy of the incident light particle must always correspond exactly to the difference in the two energy levels between which the electron is to be transferred. The researchers have used two lasers: one moved electrons between a low and a high energy level; the other between the high and a medium energy level. This middle energy level corresponds to a non-equilibrium level: the transfer to the middle level doesn’t exist without a radiative Auger process. In addition, a transition between the low and the medium energy level shouldn’t have occurred, because the relevant light was not irradiated. However, precisely this seemingly impossible transition occurred in reality due to the energy transfer from one electron to another in the radiative Auger process.
    The ultrapure semiconductor samples for the experiment were produced by Dr. Julian Ritzmann at Ruhr-Universität Bochum under the supervision of Dr. Arne Ludwig at the Chair for Applied Solid State Physics headed by Professor Andreas Wieck. The measurements were carried out by a team from the University of Basel run by Clemens Spinnler, Liang Zhai, Giang Nguyen and Dr. Matthias Löbl in the group headed by Professor Richard Warburton.
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    We might not know half of what’s in our cells, new AI technique reveals

    Most human diseases can be traced to malfunctioning parts of a cell — a tumor is able to grow because a gene wasn’t accurately translated into a particular protein or a metabolic disease arises because mitochondria aren’t firing properly, for example. But to understand what parts of a cell can go wrong in a disease, scientists first need to have a complete list of parts.
    By combining microscopy, biochemistry techniques and artificial intelligence, researchers at University of California San Diego School of Medicine and collaborators have taken what they think may turn out to be a significant leap forward in the understanding of human cells.
    The technique, known as Multi-Scale Integrated Cell (MuSIC), is described November 24, 2021 in Nature.
    “If you imagine a cell, you probably picture the colorful diagram in your cell biology textbook, with mitochondria, endoplasmic reticulum and nucleus. But is that the whole story? Definitely not,” said Trey Ideker, PhD, professor at UC San Diego School of Medicine and Moores Cancer Center. “Scientists have long realized there’s more that we don’t know than we know, but now we finally have a way to look deeper.”
    Ideker led the study with Emma Lundberg, PhD, of KTH Royal Institute of Technology in Stockholm, Sweden and Stanford University.
    In the pilot study, MuSIC revealed approximately 70 components contained within a human kidney cell line, half of which had never been seen before. In one example, the researchers spotted a group of proteins forming an unfamiliar structure. Working with UC San Diego colleague Gene Yeo, PhD, they eventually determined the structure to be a new complex of proteins that binds RNA. The complex is likely involved in splicing, an important cellular event that enables the translation of genes to proteins, and helps determine which genes are activated at which times. More