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Science, 27 SEP 2024, Volume 385 Issue 6716

"science",september 27, 2024, volume 385, issue 6716

chemicalChemistry

Solar transpiration–powered lithium extraction and storage

solar transpiration-driven lithium extraction and storage

▲ author: yan song, shiqi fang et al.

▲ link:

https://www.science.org/doi/10.1126/science.adm7034

▲ summary:

inspired by nature's selective extraction of species during transpiration, we report a solar transpiration-driven lithium extraction and storage (stles) device. the device can use natural sunlight to extract and store lithium from brine. specifically, the device uses layered solar evaporators to create a pressure gradient to extract lithium in brine and collect it in a storage layer.

long-term experiments, multiple membrane tests and evaluations of different sizes demonstrated the material's stability, compatibility and scalability. this solar mining technology offers an alternative path to sustainable extraction of critical resources.

▲ Abstract：

Inspired by nature’s ability to selectively extract species in transpiration, we report a solar transpiration–powered lithium extraction and storage (STLES) device that can extract and store lithium from brines using natural sunlight. Specifically, the device uses a hierarchically structured solar transpirational evaporator to create a pressure gradient, which allows for the extraction of lithium from brines through a membrane and its storage in a vascular storage layer. Long-term experiments, various membrane tests, and different size assessments demonstrate the stability, compatibility, and scalability of STLES. This solar-powered mining technology provides an alternative developing pathway toward the sustainable extraction of critical resources.

biologyBiology

A host-adapted auxotrophic gut symbiont induces mucosal immunodeficiency

host-adapted dystrophic intestinal commensals induce mucosal immunodeficiency

▲ author: qiuhe lu, thomas ca hitch et al.

▲ link:

https://www.science.org/doi/10.1126/science.adk2536

▲ summary:

here, we demonstrate functional screening of the bacterial microbiota of mice with low intestinal immunoglobulin a (iga) levels. we identified a species calledTomasiella immunophilagram-negative bacteria that induce and degrade iga in the mouse intestine. carryT. immunophilathe mice were susceptible to infection and had poor mucosal repair.T. immunophilait has a dystrophic defect in the bacterial cell wall amino sugar n-acetylmuramic acid.

it delivers immunoglobulin-degrading proteases into outer membrane vesicles that preferentially degrade rodent antibodies with kappa light chains rather than lambda light chains. this study demonstrates a role for commensals in immunodeficiency, which may have implications for human disease.

▲ Abstract：

We show a functional screen of the bacterial microbiota from mice with low intestinal immunoglobulin A (IgA) levels; we identified a Gram-negative bacterium, proposed as Tomasiella immunophila, that induces and degrades IgA in the mouse intestine. Mice harboring T. immunophila are susceptible to infections and show poor mucosal repair. T. immunophila is auxotrophic for the bacterial cell wall amino sugar N-acetylmuramic acid. It delivers immunoglobulin-degrading proteases into outer membrane vesicles that preferentially degrade rodent antibodies with kappa but not lambda light chains. This work indicates a role for symbionts in immunodeficiency, which might be applicable to human disease.

Prefrontal synaptic regulation of homeostatic sleep pressure revealed through synaptic chemogenetics

prefrontal synaptic regulation of homeostatic sleep pressure revealed by synaptic chemogenetics

▲ author: takeshi sawada, yusuke iino et al.

▲ link:

https://www.science.org/doi/10.1126/science.adl3043

▲ summary:

sleep is regulated by homeostatic processes, however, the biological basis for the accumulation of sleep pressure during wakefulness, triggering, and dissipation remains unclear. we explore the causal relationship between cellular synaptic strength and eeg delta power indicative of macroscopic sleep stress by developing a theoretical framework and molecular tools to manipulate synaptic strength.

mathematical models predict that increased synaptic strength promotes a "down state" of neurons and increases delta power. our molecular tools, inducing dendritic spine enlargement and synaptic potentiation through chemically induced kalirin-7 protein translocation, demonstrate that synaptic potentiation of excitatory neurons in the prefrontal cortex increases non-rapid eye movement sleep amount and delta power. thus, the synaptic strength of excitatory neurons in the prefrontal cortex determines sleep stress in mammals.

▲ Abstract：

Sleep is regulated by homeostatic processes, yet the biological basis of sleep pressure that accumulates during wakefulness, triggers sleep, and dissipates during sleep remains elusive. We explored a causal relationship between cellular synaptic strength and electroencephalography delta power indicating macro-level sleep pressure by developing a theoretical framework and a molecular tool to manipulate synaptic strength. The mathematical model predicted that increased synaptic strength promotes the neuronal “down state” and raises the delta power. Our molecular tool (synapse-targeted chemically induced translocation of Kalirin-7, SYNCit-K), which induces dendritic spine enlargement and synaptic potentiation through chemically induced translocation of protein Kalirin-7, demonstrated that synaptic potentiation of excitatory neurons in the prefrontal cortex (PFC) increases nonrapid eye movement sleep amounts and delta power. Thus, synaptic strength of PFC excitatory neurons dictates sleep pressure in mammals.

Mutating a flexible region of the RSV F protein can stabilize the prefusion conformation

mutation design for conformational stability of rsv f protein before fusion based on flexible region modification

▲ author: yu liang, shuai shao et al.

▲ link:

https://www.science.org/doi/10.1126/science.adp2362

▲ summary:

we propose a mutagenesis strategy to prevent the rsv f protein from being in its pre-f state by blocking the local changes in protein structure that accompany large-scale conformational rearrangements. we generated a series of mutants and screened them in vitro to assess their potential to form stable pre-f.

in animal experiments, the immunogenicity of a representative mutant f protein elicited neutralizing antibody levels and protection against rsv-induced lung injury comparable to ds-cav1 of pre-f used in licensed vaccines.

▲ Abstract：

We present a mutagenesis strategy to arrest the RSV F protein in its pre-F state by blocking localized changes in protein structure that accompany large-scale conformational rearrangements. We generated a series of mutants and screened them in vitro to assess their potential for forming a stable pre-F. In animals, the immunogenicity of a representative mutant F protein, with a conformation confirmed by cryo–electron microscopy, elicited levels of neutralizing antibodies and protection against RSV-induced lung damage that were comparable to those of DS-Cav1, a pre-F used in a licensed vaccine.

earth scienceEarth Science

Four decades of Hawaiian monk seal entanglement data reveal the benefits of plastic debris removal

forty years of hawaii monk seal entanglement data reveals benefits of removing plastic debris

▲ author: jason d. baker, thea c. johanos et al.

▲ link:

https://www.science.org/doi/10.1126/science.ado2834

▲ summary:

abandoned fishing gear can harm marine species and ecosystems. various cleanup programs have been established to mitigate the damage caused by this ocean plastic debris. but to our knowledge, the benefits of these efforts to marine species and ecosystems have yet to be empirically proven.

we examined hawaiian monk seal marine debris entanglement records over 40 years before and after large-scale marine debris removal efforts began in the northwestern hawaiian islands, showing that entanglement rates decreased significantly where debris removal efforts were most concentrated. large-scale, sustained removal of derelict fishing gear benefits marine ecosystems and has the potential to transform ecological restoration efforts.

▲ Abstract：

Abandoned, lost, or otherwise discarded fishing gear causes harm to marine species and ecosystems. To mitigate the destruction wrought by this ocean plastic debris, various cleanup programs have been established, though to our knowledge the benefits of such efforts to marine species and ecosystems have not yet been empirically demonstrated. We examined more than 40 years of Hawaiian monk seal marine debris entanglement records before and after large-scale marine debris removal efforts were initiated in the Northwestern Hawaiian Islands, demonstrating a substantial reduction in entanglement rates where debris removal effort was most concentrated. Large-scale and sustained removal of abandoned, lost, or otherwise discarded fishing gear meaningfully benefits marine ecosystems and has the potential to be transformational in restoration efforts.

3775-year-old wood burial supports “wood vaulting” as a durable carbon removal method

wooden burial from 3,775 years ago proves 'timber graves' could be a long-lasting carbon removal method

▲ author: ning zeng, xinpeng zhao et al.

▲ link:

https://www.science.org/doi/10.1126/science.adm8133

▲ summary:

terrestrial photosynthesis removes six times the amount of carbon dioxide emitted by fossil fuels each year. however, through decomposition most of the carbon is returned to the atmosphere. we discovered a 3,775-year-old ancient log 2 meters underground, and it has been preserved far longer than expected. the wood is nearly perfectly preserved, with less than 5% carbon loss compared to modern samples. the reason for its lack of decay may be the low permeability of the dense clay soil at the burial site.

our observations suggest that a hybrid natural engineering approach to carbon removal could be achieved by burying woody biomass in a similar anoxic environment. we estimate that using existing technology, optimized at a low cost of us$30 to us$100 per ton, the global storage potential could reach 10 billion tons of carbon dioxide per year.

▲ Abstract：

Six-times more carbon dioxide (CO2) is removed each year by terrestrial photosynthesis than fossil fuel emissions. However, the carbon is mostly returned to the atmosphere by decomposition. We found a 3775-year-old ancient wood log buried 2 meters belowground that was preserved far beyond its expected lifetime. The wood had near-perfect preservation, with carbon loss less than 5% compared to a modern sample. The lack of decay is likely due to the low permeability of the compact clay soil at the burial site. Our observation suggests a hybrid nature-engineering approach for carbon removal by burying woody biomass in similar anoxic environments. We estimate a global sequestration potential of up to 10 gigatonnes CO2 per year with existing technology at a low cost of $30 to $100 per tonne after optimization.