Porous materials for C2H2/CO2 separation mostly suffer from high regeneration energy, poor stability, or high cost that largely dampen their industrial implementation. A desired adsorbent should have ...an optimal balance between excellent separation performance, high stability, and low cost. We herein report a stable, low‐cost, and easily scaled‐up aluminum MOF (CAU‐10‐H) for highly efficient C2H2/CO2 separation. The suitable pore confinement in CAU‐10‐H can not only provide multipoint binding interactions with C2H2 but also enable the dense packing of C2H2 inside the pores. This material exhibits one of the highest C2H2 storage densities of 392 g L−1 and highly selective adsorption of C2H2 over CO2 at ambient conditions, achieved by a low C2H2 adsorption enthalpy (27 kJ mol−1). Breakthrough experiments confirm its exceptional separation performance for C2H2/CO2 mixtures, affording both large C2H2 uptake of 3.3 mmol g−1 and high separation factor of 3.4. CAU‐10‐H achieves the benchmark balance between separation performance, stability, and cost for C2H2/CO2 separation.
An ultra‐microporous Al‐MOF with suitable pore confinement enables the dense packing of C2H2 molecules for efficient C2H2/CO2 separation, exhibiting the benchmark balance between high separation performance, low cost, high stability, and large‐scale synthesis for industrial applications.
Developing porous materials for C3H6/C3H8 separation faces the challenge of merging excellent separation performance with high stability and easy scalability of synthesis. Herein, we report a robust ...Hofmann clathrate material (ZJU‐75a), featuring high‐density strong binding sites to achieve all the above requirements. ZJU‐75a adsorbs large amount of C3H6 with a record high storage density of 0.818 g mL−1, and concurrently shows high C3H6/C3H8 selectivity (54.2) at 296 K and 1 bar. Single‐crystal structure analysis unveil that the high‐density binding sites in ZJU‐75a not only provide much stronger interactions with C3H6 but also enable the dense packing of C3H6. Breakthrough experiments on gas mixtures afford both high separation factor of 14.7 and large C3H6 uptake (2.79 mmol g−1). This material is highly stable and can be easily produced at kilogram‐scale using a green synthesis method, making it as a benchmark material to address major challenges for industrial C3H6/C3H8 separation.
A novel strategy that incorporates high‐density strong binding sites into ultra‐microporous Hofmann clathrate material for dense packing of C3H6 molecules is reported. The use of this new porous material not only overcomes the trade‐off between uptake capacity and selectivity but also combines excellent separation performance with high stability, economic feasibility and easy scalability of synthesis.
Developing porous materials to overcome the trade‐off between adsorption capacity and selectivity for C2H2/CO2 separation remains a challenge. Herein, we report a stable HKUST‐1‐like MOF (ZJU‐50a), ...featuring large cages decorated with high density of supramolecular binding sites to achieve both high C2H2 storage and selectivity. ZJU‐50a exhibits one of the highest C2H2 storage capacity (192 cm3 g−1) and concurrently high C2H2/CO2 selectivity (12) at 298 K and 1 bar. Single‐crystal X‐ray diffraction studies on gas‐loaded ZJU‐50a crystal unveil that the incorporated supramolecular binding sites can selectively take up C2H2 molecule but not CO2 to result in both high C2H2 storage and selectivity. Breakthrough experiments validated its separation performance for C2H2/CO2 mixtures, providing a high C2H2 recovery capacity of 84.2 L kg−1 with 99.5 % purity. This study suggests a novel strategy of engineering supramolecular binding sites into MOFs to overcome the trade‐off for this separation.
We developed a novel strategy by engineering abundant supramolecular binding sites into a chemically stable HKUST‐1‐like MOF (ZJU‐50a) to achieve simultaneously high C2H2 storage and selectivity, breaking the trade‐off between adsorption capacity and selectivity for C2H2/CO2 separation.
Under global warming, a novel category of extreme events has become increasingly apparent, where flood and hot extremes occur in rapid succession, causing significant damages to infrastructure and ...ecosystems. However, these bivariate compound flood‐hot extreme (CFH) hazards have not been comprehensively examined at the global scale, and their evolution under climate warming remains unstudied. Here, we present the first global picture of projected changes in CFH hazards by using a cascade modeling chain of CMIP6 models, satellite and reanalysis data sets, bias correction, and hydrological models. We find an increasing percentage of floods will be accompanied by hot extremes under climate change; the joint return periods of CFHs are projected to decrease globally, particularly in the tropics. These decreasing joint return periods are largely driven by changes in hot extremes and indicate a likely increase of CFH hazards, and ultimately highlight the urgent need to conduct adaptation planning for future risks.
Plain Language Summary
Climate change alters the Earth's energy budget and accelerates the hydrological cycle, bringing new hazards such as temporally compounding flood and hot extremes. Rapid transitions from devastating floods to deadly heat, or vice versa, which used to be rare, are already occurring under the present climate and bring new threats to infrastructure and the public. However, these bivariate CFH hazards have been poorly understood at the global scale, and their future evolution in the context of climate change has not yet been assessed. Here, we provide the first systematic assessment of projected changes and attributions in the multivariate hazards of global flood‐hot extremes. We find that the fraction of flooding accompanied by hot extremes could rise markedly under global warming. Changes in hot extremes dominate the exacerbation of global CFH hazards, especially in tropical climate zones. Our study identifies the tropics as the new global hotspot of flood‐hot extreme events in a warming future, and reveals an increasing global risk of unexpected sequential wet‐hot extremes, highlighting the need to better prepare adaptation and mitigation solutions.
Key Points
We present the first global assessment of projected changes in compound river flood‐hot extremes
Future flood‐hot extremes are mainly driven by changes in hot extremes
Substantial increases in compound flood‐hot extremes are projected in tropical regions
MicroRNA‐24‐3p (miR‐24‐3p) has been implicated as a key promoter of chemotherapy resistance in numerous cancers. Meanwhile, cancer‐associated fibroblasts (CAFs) can secret exosomes to transfer ...miRNAs, which mediate tumour development. However, little is known regarding the molecular mechanism of CAF‐derived exosomal miR‐24‐3p in colon cancer (CC). Hence, this study intended to characterize the functional relevance of CAF‐derived exosomal miR‐24‐3p in CC cell resistance to methotrexate (MTX). We identified differentially expressed HEPH, CDX2 and miR‐24‐3p in CC through bioinformatics analyses, and validated their expression in CC tissues and cells. The relationship among HEPH, CDX2 and miR‐24‐3p was verified using ChIP and dual‐luciferase reporter gene assays. Exosomes were isolated from miR‐24‐3p inhibitor–treated CAFs (CAFs‐exo/miR‐24‐3p inhibitor), which were used in combination with gain‐of‐function and loss‐of‐function experiments and MTX treatment. CCK‐8, flow cytometry and colony formation assays were conducted to determine cell viability, apoptosis and colony formation, respectively. Based on the findings, CC tissues and cells presented with high expression of miR‐24‐3p and low expression of HEPH and CDX2. CDX2 was a target gene of miR‐24‐3p and could up‐regulate HEPH. Under MTX treatment, overexpressed CDX2 or HEPH and down‐regulated miR‐24‐3p reduced cell viability and colony formation and elevated cell apoptosis. Furthermore, miR‐24‐3p was transferred into CC cells via CAF‐derived exosomes. CAF‐derived exosomal miR‐24‐3p inhibitor diminished cell viability and colony formation and increased cell apoptosis in vitro and inhibited tumour growth in vivo under MTX treatment. Altogether, CAF‐derived exosomal miR‐24‐3p accelerated resistance of CC cells to MTX by down‐regulating CDX2/HEPH axis.
Separation of acetylene (C
2
H
2
) from ethylene (C
2
H
4
) and carbon dioxide (CO
2
) is of great importance in the petrochemical industry but remains a daunting challenge due to their very similar ...sizes and physical properties. Although a number of porous materials have been developed as promising adsorbents for either C
2
H
2
/C
2
H
4
or C
2
H
2
/CO
2
separation, few materials exhibit simultaneously high selectivities for both gas mixtures. Herein, we report the use of a four-connected N-donor organic linker to construct a novel water-stable SIFSIX-type material, Cu(TPB)SiF
6
n
(termed ZJU-280, TPB = 1,2,4,5-tetra(pyridin-4-yl)benzene). This material features suitable rhombic pores and functional surfaces to interact optimally with C
2
H
2
molecules, affording high C
2
H
2
capture capacity and simultaneously high C
2
H
2
/CO
2
(18.1) and C
2
H
2
/C
2
H
4
(44.5) selectivities under ambient conditions. Theoretical calculations indicate that the suitable rhombic pores and functional sites can provide a multipoint binding environment to not only preferentially interact with C
2
H
2
but also enable the dense packing of C
2
H
2
molecules within the framework. Actual breakthrough experiments demonstrate that ZJU-280a can efficiently separate C
2
H
2
from C
2
H
2
/CO
2
(50/50, v/v) and C
2
H
2
/C
2
H
4
(1/99 and 50/50) mixtures, respectively.
A novel water-stable anion-pillared MOF material with suitable rhombic pores and functional surfaces exhibits high C
2
H
2
capture capacity and simultaneously high C
2
H
2
/CO
2
and C
2
H
2
/C
2
H
4
selectivities under ambient conditions.
As atmospheric moisture holding capacity is positively dependent on temperatures, a large intensification of precipitation extremes is projected under foreseeable climate warming. Flooding that is ...mainly attributed to extreme storms usually accounts for an ambitious target in weather‐related hazard mitigation over China. Previous works seldom focused on flooding evolution patterns under climate change at a national scale, and fewer flooding projections considered the estimation uncertainty sourced from limited samples. This study systematically projected changes in flood quantiles based on annual maximum series and seasonality and also evaluated the variations of sampling uncertainty for 151 catchments over mainland China under the emission scenario of representative concentration pathway (RCP) 8.5. In order to project future streamflow series, the bias‐corrected outputs of six global climate models (GCMs) were input into a best‐performing hydrological model, which was selected from four calibrated hydrological models based on the KGE criteria. The Pearson type‐III (P‐III) distribution and L‐moments (L‐M) method were employed to derive the flood quantiles for different return periods during historical (1961–2005) and future (2056–2100) periods, and the bootstrapping method was applied to estimate the sampling uncertainty. A regression trend method was used to track the variations of flood seasonality in the context of climate warming. Our results project earlier flood timing and larger flood quantiles for most catchments in future period than those in the historical period, despite being accompanied by substantial spatial variations. We also project that the sampling uncertainty in estimating flood quantiles is increased in a warming future. Many catchments are exposed to dramatic changes in both flood quantile and estimation uncertainty by over 50%, while only a few catchments are projected to have decreasing flood risks. These results suggest an urgent need to improve the functionality of early warning systems and increase societal resilience to warming climates over China.
Projected changes in flood dynamics and estimation uncertainty are evaluated for 151 catchments over mainland China.
The bias‐corrected multi‐model climate ensemble outputs are combined with four hydrological models to project hydrological scenarios.
The floods will occur earlier under future climate warming in most catchments.
The flood quantiles and sampling uncertainty are both projected to increase by over 50% for most catchments in a warming future.
Anthropogenic climate warming is expected to accelerate the hydrological cycle with significant consequences for hydrological droughts. However, a systematic understanding of climate warming impacts ...on the global hydrological droughts and their driving mechanisms is still lacking. Here, we integrate bias‐corrected climate experiments, multiple hydrological models (HYs), and a multivariate analysis of variance (ANOVA) with a machine learning modeling framework, to examine the evolving frequency and multivariate characteristics of hydrological droughts and their mechanisms under climate warming for 6,688 catchments in the five principal Köppen‐Geiger climate zones. Results show that the total frequency of hydrological droughts is likely to stay unchanged while extreme hydrological droughts (e.g., events with a 30 yr joint return period, JRP) are projected to occur more frequently across the 21st century. The historical 30 yr JRP events assessed during the historical baseline period of 1985–2014 could become twice as frequent over ∼60% of global catchments by 2071–2100 under the middle and high emission scenarios (ESs). Climate uncertainty (i.e., from global climate models and ESs) is the major source of uncertainty over temperate and tropical catchments, versus HY uncertainty in arid catchments with locally complex runoff regimes. Our machine learning framework indicates that precipitation stress controls the development of historical droughts over ∼87% of global catchments. However, with climate warming, air temperature variations are expected to become the new primary driver of droughts in high‐latitude cold catchments. This study highlights an increasing risk of global extreme hydrological droughts with warming and suggests that rising temperatures in high latitudes may lead to more extreme hydrological droughts.
Key Points
Impacts of climate change on hydrological droughts are assessed in 6,688 catchments worldwide
Total frequency of droughts is projected to stay unchanged while the frequency of extreme episodes may increase significantly with warming
Air temperature variation, rather than precipitation, is the main factor driving future drought development in high‐latitude catchments
Oxidative stress is a major cause of adverse outcomes in preeclampsia (PE). Ferroptosis, i.e. programmed cell death from iron-dependent lipid peroxidation, likely mediates PE pathogenesis. We ...evaluated specific markers for ferroptosis in normal and PE placental tissues, using in vitro (trophoblasts) and in vivo (rat) models. Increase in malondialdehyde content and total Fe2+ along with reduced the glutathione content and glutathione peroxidase activity was observed in PE placenta. While the trophoblasts experienced death under hypoxia, inhibitors of ferroptosis, apoptosis, autophagy, and necrosis increased the cell viability. Microarrays, bioinformatic analysis, and luciferase reporter assay revealed that upregulation of miR-30b-5p in PE models plays a pivotal role in ferroptosis, by downregulating Cys2/glutamate antiporter and PAX3 and decreasing ferroportin 1 (an iron exporter) expression, resulting in decreased GSH and increased labile Fe2+. Inhibition of miR-30b-5p expression and supplementation with ferroptosis inhibitors attenuated the PE symptoms in rat models, making miR-30b-5p a potential therapeutic target for PE.
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