Plant Leaves Absorb Airborne Microplastics, Raising Concerns About Food Chain Contamination

Hello and welcome to our April 15th edition. The STEAM Digest is a curated newsletter that brings you the latest news in science, technology, engineering, arts, and mathematics.

In today’s edition:

• Science - Earth’s Magnetic Field Harnessed to Create Novel Nanomaterials in Groundbreaking Fluidic Study, and more.

• Materials - Harvard Engineers Create Bilayer Metasurface for Unprecedented Control of Light, and more.

• Biotechnology & Biomedical Technology - Engineered Gut Bacteria Boost Nanoparticle Production for Drug Delivery and Vaccine Development, and more.

• Astronomy, Space, Astrobiology - NASA Confirms Solar Wind Can Create Water on the Moon in Landmark Lab Experiment.

• Engineering & Technology -UC Berkeley-Led Team Develops Stretchable, Self-Healing Lithium Battery for Wearable Tech.

• Robotics - UT Dallas Researchers Develop Low-Cost, Mandrel-Free Artificial Muscles for Wearables and Robotics.

• Health & Medicine - New Microfluidic Chip Mimics Cancer-Blood Vessel Interactions, Paving the Way for Personalized Drug Testing, and more.

• Neuroscience - Year-Long Brain Stimulation Slows Alzheimer's Progression in Clinical Trial, and more.

• Environment - Plant Leaves Absorb Airborne Microplastics, Raising Concerns About Food Chain Contamination, and more.

• Nature - Crows Recognize Geometric Regularity, Joining Humans in Rare Cognitive Skill, and more.

Until Tomorrow,

~The STEAM Digest

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SCIENCE

Earth’s Magnetic Field Harnessed to Create Novel Nanomaterials in Groundbreaking Fluidic Study: In a world-first, scientists have demonstrated that the Earth’s magnetic field can influence fluid dynamics to create new nanoparticles and chiral materials, opening fresh frontiers in nanotechnology and sustainable chemistry. The study shows how spinning fluids in a vortex fluidic device (VFD) can produce left- or right-handed nanostructures depending on magnetic field orientation and device rotation. Experiments conducted across both hemispheres confirmed the influence of Earth’s geomagnetic field on fluid behavior. This breakthrough not only challenges conventional physics but also simplifies nanofabrication processes, enabling greener production of pharmaceuticals, metamaterials, and components with potential applications in quantum technologies. The research builds on earlier achievements using the VFD, such as separating proteins and extracting DNA, and hints at even broader possibilities in materials science and energy-efficient manufacturing.

How Bacteria Outsmart Plant Defenses: New Insights into Redox Sensing in Agrobacterium: Researchers have uncovered how the plant pathogen Agrobacterium tumefaciens detects and defends against reactive oxygen species (ROS)—toxic molecules produced by plants to fend off infections. The study identifies and characterizes the redox sensor LsrB, which works alongside a previously known sensor, OxyR. Both are transcription factors that regulate bacterial responses to oxidative stress. High-resolution cryo-electron microscopy revealed that LsrB uses four cysteine residues to detect redox changes. When either sensor is removed, bacteria become highly vulnerable to plant defenses, highlighting their crucial role in infection. Unlike OxyR, which specifically senses ROS, LsrB appears to have a broader regulatory function, possibly linking stress response with virulence. These findings may pave the way for new approaches in agriculture and biotechnology by targeting or enhancing bacterial regulatory networks.

Researchers Achieve Low-Temperature Propane Dehydrogenation Using Solar-Driven Water-Catalyzed Reaction: Researchers have developed a groundbreaking method for propane dehydrogenation (PDH) using a copper single-atom catalyst (Cu₁/TiO₂ SAC) and water vapor under light exposure. The study demonstrates efficient conversion of propane to propylene at just 50–80 °C—far below the >600 °C required in conventional PDH. This mild photo-thermo catalytic route leverages hydroxyl radicals generated through photocatalytic water splitting to drive hydrogen abstraction from propane, with water acting catalytically and not being consumed. The reaction can also be extended to other light alkanes and driven directly by sunlight, setting a new paradigm for solar-powered high-temperature chemical processes.

MATERIALS

Harvard Engineers Create Bilayer Metasurface for Unprecedented Control of Light: Researchers have developed a groundbreaking bilayer metasurface that significantly enhances control over light’s properties—including wavelength, phase, and polarization. The new device features two stacked layers of titanium dioxide nanostructures, forming a 3D array akin to microscopic skyscrapers. Unlike traditional single-layer metasurfaces, which face limitations in light manipulation, this bilayer structure enables more complex, multifunctional optical behaviors—such as projecting different images from opposite sides. The team overcame major fabrication challenges using advanced nanotechnology methods. This innovation builds on Harvard’s earlier metalens work and may revolutionize applications in imaging, AR/VR, telecommunications, and optical computing by enabling more compact and versatile light-based devices.

Low-Temperature Defect Repair in MoS₂ Advances Next-Gen Semiconductor Development: Researchers have developed a breakthrough low-temperature method to eliminate sulfur vacancy defects in molybdenum disulfide (MoS₂)—a promising material for future low-power semiconductor chips. The study introduces a process using pentafluorobenzenethiol (PFBT) at just 200°C to restore the Mo:S atomic ratio from 1:1.68 to a near-ideal 1:1.98, significantly improving electronic performance. This low-temperature repair is fully compatible with existing silicon chip fabrication methods, which require careful thermal limits. Devices made with the treated MoS₂ demonstrated 2.5x higher charge mobility and 40% lower power consumption. The technique could accelerate the integration of MoS₂ and similar 2D materials into future chip designs.

Monash University Develops Advanced Graphene Membrane to Effectively Remove PFAS from Water: Researchers have created a groundbreaking water filtration membrane capable of efficiently removing even the smallest PFAS ("forever chemicals") molecules—something traditional filters struggle to achieve. The study introduces a beta-cyclodextrin-modified graphene oxide (GO-βCD) membrane with nanoscale channels that selectively block PFAS while allowing water and essential nutrients to pass. This novel membrane forms a strong energetic barrier to PFAS, outperforming standard polyamide filters, which typically remove only about 35% of short-chain PFAS. Developed using scalable shear alignment printing, the technology holds promise for large-scale deployment in drinking water, industrial wastewater, and landfill leachate treatment.

BIOTECHNOLOGY & BIOMEDICAL TECHNOLOGY

Engineered Gut Bacteria Boost Nanoparticle Production for Drug Delivery and Vaccine Development: A team of researchers has developed a method to dramatically increase the production of bacterial membrane vesicles (BMVs) by modifying common gut bacteria. These nanoparticles, valuable for drug delivery, cancer therapy, and vaccines, were produced at 140 times the usual rate through genetic alterations, including the insertion of a shell protein. This innovation eliminates the need for chemical enhancers and enables cleaner, more sustainable production. The engineered bacteria successfully activated immune responses in the gut and demonstrated targeted movement through the digestive tract, making them promising tools for treating conditions like Inflammatory Bowel Disease (IBD) and delivering nutrients or drugs. Researchers are now exploring the application of this method to vaccine-producing bacteria and developing probiotic supplements to enhance nutrient absorption.

New Class of Targeted Enzyme Inhibitors Offers Hope for Cancer and Autoimmune Therapies: Scientists have developed a novel class of highly selective inhibitors targeting the enzymes DPP8 and DPP9—key regulators of inflammation and cell survival, particularly in cancer cells. These new compounds, derived from the natural inhibitor Sulphostin and refined at the molecular level into N-phosphonopiperidones, demonstrate precise inhibition of DPP8/9 with minimal impact on other cellular processes. This marks a major advancement over previous drugs, which often caused unwanted side effects due to low specificity. The findings offer a promising path toward more effective cancer treatments and therapies for inflammatory or autoimmune diseases.

New “Patchy” Thermogels Offer Promising Injectable Solution for Tissue Regeneration: Researchers have developed an innovative design for thermogels—injectable materials that turn from liquid to solid at body temperature—which could significantly advance minimally invasive treatments like drug delivery and soft tissue regeneration. The new thermogels are built from "patchy" micelles—nanoparticles with sticky zones that assemble more predictably and form stronger, more stable gel structures than traditional designs. This approach improves mechanical properties and allows customization for specific biomedical applications. The materials may eventually replace surgical procedures in some cases, offering a less invasive alternative for wound healing and tissue scaffolding after surgeries, such as cancer removals. Further testing is planned in biological systems.

Scientists Use Magnetic Fields to Control Virus-Based Self-Assembly: Researchers have developed a novel method to control the self-assembly of rod-shaped viruses using magnetic fields, potentially revolutionizing artificial self-assembly processes. The study reveals how chirality—a natural twist between neighboring virus particles—limits the size of self-assembled disks. By applying a magnetic field, the team reduced this twist, enabling the formation of larger structures. Once the magnetic field was turned off, the disks slowly unraveled into corkscrew-like shapes. This adaptive, tunable method surpasses natural systems in flexibility and could pave the way for innovative applications in nanotechnology, such as smart materials or microscopic surgical tools. The work brings researchers closer to mimicking—and even exceeding—the efficiency and precision of biological self-assembly.

ASTRONOMY, SPACE, ASTROBIOLOGY

NASA Confirms Solar Wind Can Create Water on the Moon in Landmark Lab Experiment: NASA-led researchers have confirmed that the Sun’s solar wind can generate water on the Moon, validating a decades-old hypothesis. In a groundbreaking study scientists used a custom-built, contamination-free lab setup to simulate the Moon’s environment and bombard Apollo 17 lunar soil samples with charged particles mimicking the solar wind. The result: a chemical reaction between solar hydrogen and oxygen in lunar minerals produced hydroxyl and likely water molecules. This discovery has significant implications for NASA’s Artemis missions, suggesting that the Moon's water content is replenished daily by solar wind and could be harnessed as a resource at the lunar poles. While the exact amounts are tiny, the findings deepen our understanding of lunar chemistry and point to sustainable in-situ resource utilization for future exploration

ENGINEERING & TECHNOLOGY

UC Berkeley-Led Team Develops Stretchable, Self-Healing Lithium Battery for Wearable Tech: Researchers have created a stretchable, self-healing lithium-ion battery that retains stability after 500 charge cycles and withstands extreme mechanical stress. The battery is made with a zwitterionic polymer that tightly binds water and facilitates lithium ion movement while minimizing water splitting. A fluorine-free hydrogel electrolyte and acrylic acid cross-linker contribute to its flexibility, durability, and environmental stability. The battery maintained function after being stretched, folded, punctured, and cut—making it ideal for future wearable electronics. It successfully powered LED circuits for over a month in 50% humidity, demonstrating its resilience and potential for next-generation flexible devices.

ROBOTICS

Researchers Develop Low-Cost, Mandrel-Free Artificial Muscles for Wearables and Robotics: Researchers have unveiled a cost-effective, mandrel-free technique to fabricate high-performance artificial muscles. The team developed a new method for creating thermally responsive, coiled polymer fibers with a high spring index—up to 50—that can stretch up to 97% of their original length. Unlike previous methods that required disposable mandrels, this new technique uses twisted fibers that coil together, with each fiber serving as a mandrel for the others, eliminating material waste. Potential applications include smart clothing that adapts to temperature, robotic actuators, energy harvesters, and strain sensors. The advance revives commercial viability for products like the Olympic jackets previously developed with older, costlier processes.

HEALTH & MEDICINE

New Microfluidic Chip Mimics Cancer-Blood Vessel Interactions, Paving the Way for Personalized Drug Testing: Researchers have developed a groundbreaking microfluidic device—dubbed the ODSEI (Open-structured Double-layer Spheroid-Endothelium Interaction) Chip—that accurately simulates the interactions between cancer cells and blood vessels. The chip enables large-scale, real-time analysis of over 1,000 tumor spheroids in conjunction with vascular cells. It uniquely maintains an open structure for easy sampling and analysis, facilitating advanced studies into cancer metastasis and drug resistance. Using the chip, the team identified IL-8 and TIMP-1 as key molecules involved in breast cancer resistance to tamoxifen, offering insights into how cancer cells evade treatment. This innovation marks a significant step toward patient-specific cancer therapies by recreating complex tumor microenvironments with high precision.

Researchers Develop Promising Oral Drug Cocktail to Halt Enterovirus Replication: A team of researchers has identified a promising combination of existing drugs that can stop enteroviruses—culprits behind illnesses ranging from the common cold to polio and meningitis—from replicating in human cells. The study highlights a trio of orally-administered drugs: pleconaril, AG7404, and mindeudesivir, which together block viral replication without affecting insulin levels or heart rate in lab-grown mini-organs. Earlier drug combinations, including remdesivir and rupintrivir, showed effectiveness but lacked practicality as oral medications. The new cocktail, effective in cell cultures and organoid models, could offer a broad-spectrum treatment for a major global health threat, pending further studies and human clinical trials.

Researchers Uncover Link Between Body Fat and Anxiety Through Stress-Triggered Hormone: A groundbreaking study has revealed a direct connection between adipose tissue (body fat) and anxiety. Researchers found that psychological stress activates lipolysis in fat cells, leading to the release of fats and the hormone GDF15 from immune cells in adipose tissue. GDF15 then signals the brain, triggering anxiety-like responses. Using behavioral and molecular analyses in mice, the team identified a novel metabolic pathway linking fat metabolism to mental health. These insights could pave the way for new treatments targeting metabolic processes to manage anxiety. Since GDF15 blockers are already under development for cancer, they may hold future potential as anxiety therapies.

NEUROSCIENCE

Year-Long Brain Stimulation Slows Alzheimer's Progression in Clinical Trial: A new study reveals that repetitive transcranial magnetic stimulation (rTMS) targeting the brain’s precuneus region may significantly slow cognitive and functional decline in patients with mild-to-moderate Alzheimer’s disease. In a 52-week randomized, double-blind trial involving 48 participants, those receiving rTMS showed slower deterioration across multiple clinical measures, including cognition, daily functioning, and behavioral symptoms, compared to a sham group. rTMS-treated patients demonstrated smaller declines on assessments such as the Clinical Dementia Rating Scale and Mini-Mental State Examination. The treatment also appeared to reduce apathy and appetite-related symptoms. Personalized stimulation using TMS-EEG ensured accurate targeting. The therapy was well tolerated, and its potential to maintain patient autonomy suggests it could reduce caregiver burden. Larger multi-site trials are needed to validate and expand on these findings, especially in combination with pharmacological treatments.

Smallest Vision Control System in Mammals Mapped, Revealing Key to Eye-Brain Communication: In a groundbreaking study an international research team has, for the first time, mapped the smallest known control system of vision in mammals. Focusing on inhibitory signaling in the retina—where visual processing begins—the team identified 44 distinct visual cell types, some previously unknown, organized in a surprisingly systematic way. Central to the discovery was a newly developed GABA sensor, enabling real-time mapping of inhibitory (or "brake") neuron activity. This breakthrough reveals how the retina processes movement and orientation and may shed light on vision-related disorders such as congenital nystagmus, which are linked to imbalances in these signaling systems. The findings offer a detailed roadmap for future research into visual processing and neurological eye diseases.

ENVIRONMENT

Plant Leaves Absorb Airborne Microplastics, Raising Concerns About Food Chain Contamination: Researchers have discovered that plant leaves can directly absorb airborne microplastics (MPs), providing clear evidence that atmospheric exposure is a major route for plastic accumulation in vegetation. The study found significant concentrations of polyethylene terephthalate (PET) and polystyrene (PS) in plant leaves collected from diverse environments—including industrial, urban, and agricultural sites. Laboratory experiments with maize confirmed rapid foliar uptake of PET through stomata, with particles translocating to vascular tissue and trichomes. Notably, older and outer leaves showed higher plastic concentrations, and open-air crops contained more MPs than those grown in greenhouses. This finding highlights the potential for widespread entry of microplastics into the food chain, underscoring the need for further research into ecological and health impacts.

Climate Change and Human Activity Drive Remarkable Greening of India's Thar Desert: A study reveals that the Thar Desert has undergone significant vegetation growth—up 38% since 2001—due to increased monsoon rainfall, climate change, and intensified groundwater pumping. Satellite data, climate records, and hydrological measurements show that rainfall contributed 66% of greening during monsoons, while groundwater played a dominant role (67%) in dry months. Over the past two decades, urban areas in the region expanded by up to 800%, and agricultural land by 300%, fueled largely by groundwater extraction. Despite the ecological gains, the study warns of long-term groundwater depletion, raising concerns over the sustainability of this growth. As the region faces rising temperatures and water stress, future greening will depend on improved water management, drought-resilient crops, and renewable-powered irrigation systems to ensure food and water security for the desert’s growing population.

Masked Shrews Shrink Their Bodies and Skulls to Survive Winter, Study Shows:
New research reveals that masked shrews (Sorex cinereus), small insect-eating mammals in the Appalachian Mountains, reduce their body mass by 13% during winter to conserve energy—a striking example of Dehnel’s phenomenon. The study also documented seasonal shrinkage in the animals’ braincases and femurs, showing extensive skeletal remodeling. This physiological adaptation, a form of phenotypic plasticity, is more extreme than common survival strategies like hibernation. By analyzing 125 shrews captured in North Carolina and combining findings with 74 global studies, the team found that colder seasonal temperatures predict the degree of body and skull shrinkage. The findings help illuminate how mammals may adapt to climate change through physical flexibility.

NATURE

Crows Recognize Geometric Regularity, Joining Humans in Rare Cognitive Skill:
In a groundbreaking study researchers have shown that carrion crows possess the rare ability to recognize geometric regularity—previously observed only in humans. The crows were tested using touchscreens where they had to identify the "odd one out" among various geometric shapes, such as spotting a star among rectangles. The birds consistently chose correctly, even when the differences were subtle, demonstrating an intuitive grasp of shapes, symmetry, right angles, and parallel lines. Remarkably, they performed these tasks without prior training, suggesting an innate cognitive ability. These findings challenge the belief that such abstract visual reasoning is uniquely human and imply that other intelligent animals may share similar skills.

Dogs Can Understand Human Speech Even Without “Baby Talk,” New Study Finds: A new study reveals that dogs can recognize meaningful speech content—even when spoken in a flat, monotonous tone—highlighting their advanced listening abilities. The study found that dogs responded to familiar commands buried in irrelevant speech, indicating they can passively process language much more effectively than previously believed. This challenges the assumption that dogs only respond to exaggerated, cheerful tones known as dog-directed speech (DDS). The results suggest dogs possess the neural capacity for speech recognition and may have evolved specialized skills for understanding human communication through domestication. These findings could influence future approaches in training service dogs and deepen our understanding of human-animal interaction.