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China has large, estimated potential for direct air carbon capture and storage (DACCS) but its deployment locations and impacts at the subnational scale remain unclear. This is largely because higher spatial resolution studies on carbon dioxide removal (CDR) in China have focused mainly on bioenergy with carbon capture and storage. This study uses a spatially detailed integrated energy-economy-climate model to evaluate DACCS for 31 provinces in China as the country pursues its goal of climate neutrality by 2060. We find that DACCS could expand China’s negative emissions capacity, particularly under sustainability-minded limits on bioenergy supply that are informed by bottom-up studies. But providing low-carbon electricity for multiple GtCO₂yr⁻¹DACCS may require over 600 GW of additional wind and solar capacity nationwide and comprise up to 30% of electricity demand in China’s northern provinces. Investment requirements for DACCS range from $330 to $530 billion by 2060 but could be repaid manyfold in the form of avoided mitigation costs, which DACCS deployment could reduce by up to $6 trillion over the same period. Enhanced efforts to lower residual CO₂emissions that must be offset with CDR under a net-zero paradigm reduce but do not eliminate the use of DACCS for mitigation. For decision-makers and the energy-economy models guiding them, our results highlight the value of expanding beyond the current reliance on biomass for negative emissions in China.

 

The 3D bioprinting of aquatic photosynthetic organisms holds potential for applications in biosensing, wastewater treatment, and biofuel production. While algae cells can be immobilized in bioprinted cell‐friendly matrices, there is a knowledge gap regarding the thresholds of hydrodynamic shear stress that affect the cells’ functionality and viability during bioprinting. This study examines the effect of hydrodynamic shear stress on the fate ofChlamydomonas reinhardtiicells. Computational fluid dynamics models based on the Navier–Stokes equations are developed to numerically predict the shear stresses experienced by the cells during extrusion. Parallelly, cell culture experiments are conducted to evaluate the functionality, growth rates, and viability of algae cells within bioprinted constructs. By correlating cell culture and simulation results, the causal link between shear stress in the nozzle and cell viability and function has been characterized. The findings highlight that cell viability and function are significantly impacted by process factors. Notably, algae cell function is more sensitive to shear stress than cell viability. Functional impairments occur at maximum shear stresses around 5 kPa, while viability remains unaffected. Beyond 14 kPa, both functionality and viability decline significantly and irreversibly. The results emphasize the importance of assessing viability and function after bioprinting, rather than just viability.

 

The implementation of synthetic polymer membranes in gas separations, ranging from natural gas sweetening, hydrogen separation, helium recovery, carbon capture, oxygen/nitrogen enrichment, etc. , has stimulated the vigorous development of high-performance membrane materials. However, size-sieving types of synthetic polymer membranes are frequently subject to a trade-off between permeability and selectivity, primarily due to the lack of ability to boost fractional free volume while simultaneously controlling the micropore size distribution. Herein, we review recent research progress on microporosity manipulation in high-free-volume polymeric gas separation membranes and their gas separation performance, with an emphasis on membranes with hourglass-shaped or bimodally distributed microcavities. State-of-the-art strategies to construct tailorable and hierarchically microporous structures, microporosity characterization, and microcavity architecture that govern gas separation performance are systematically summarized. 

Modified nucleotides in non-coding RNAs, such as tRNAs and snRNAs, represent an important layer of gene expression regulation through their ability to fine-tune mRNA maturation and translation. Dysregulation of such modifications and the enzymes installing them have been linked to various human pathologies including neurodevelopmental disorders and cancers. Several methyltransferases (MTases) are regulated allosterically by human TRMT112 (Trm112 in Saccharomyces cerevisiae), but the interactome of this regulator and targets of its interacting MTases remain incompletely characterized. Here, we have investigated the interaction network of human TRMT112 in intact cells and identify three poorly characterized putative MTases (TRMT11, THUMPD3 and THUMPD2) as direct partners. We demonstrate that these three proteins are active N2-methylguanosine (m2G) MTases and that TRMT11 and THUMPD3 methylate positions 10 and 6 of tRNAs, respectively. For THUMPD2, we discovered that it directly associates with the U6 snRNA, a core component of the catalytic spliceosome, and is required for the formation of m2G, the last ‘orphan’ modification in U6 snRNA. Furthermore, our data reveal the combined importance of TRMT11 and THUMPD3 for optimal protein synthesis and cell proliferation as well as a role for THUMPD2 in fine-tuning pre-mRNA splicing.

 

Polymer confinement is realized in hybrid nanocomposites where individual polymer molecules are confined by a nanoporous matrix to dimensions less than the molecular size of the polymer. Here it is shown that by functionalizing the interior pore surfaces of a nanoporous organosilicate matrix, the pores can be filled with polystyrene molecules to achieve extreme levels of molecular confinement not previously possible. This provides opportunities for unique thermal and mechanical properties. It is shown that pore surface functionalization markedly impacts the polymer mobility during polymer infiltration by affecting the polymer–pore surface interaction, addressing the challenge of filling high‐molecular‐weight polymer molecules into nanoscale‐confined spaces. This allows for achieving extreme levels of molecular confinement with the loss of interchain entanglement and extensive polymer elongation along the pore axis. The glass transition temperature of the polymer is suppressed compared to bulk polymer melt, and is significantly affected by the polymer–surface interaction, which changes the polymer segmental mobility. The polymer–surface interaction also affects the interfacial polymer–pore sliding shear stress during polymer pullout from the nanopores, markedly affecting the fracture resistance of the nanocomposite.

 

Transmembrane serine proteases have been implicated in the development and progression of solid and hematological cancers. Human airway trypsin‐like protease 4 (HAT‐L4) is a transmembrane serine protease expressed in epithelial cells and exocrine glands. In the skin, HAT‐L4 is important for normal epidermal barrier function. Here, we report an unexpected finding of ectopic HAT‐L4 expression in neutrophils and monocytes from acute myeloid leukemia (AML) patients. Such expression was not detected in bone marrow cells from normal individuals or patients with chronic myeloid leukemia, acute lymphocytic leukemia and chronic lymphocytic leukemia. In AML patients who underwent chemotherapy, persistent HAT‐L4 expression in bone marrow cells was associated with minimal residual disease and poor prognostic outcomes. In culture, silencing HAT‐L4 expression in AML–derived THP‐1 cells by short hairpin RNAs inhibited matrix metalloproteinase‐2 activation and Matrigel invasion. In mouse xenograft models, inhibition of HAT‐L4 expression reduced the proliferation and growth of THP‐1 cell–derived tumors. Our results indicate that ectopic HAT‐L4 expression is a pathological mechanism in AML and that HAT‐L4 may be used as a cell surface marker for AML blast detection and targeting.