The proliferation of pulmonary artery smooth muscle cells (PASMCs) is an important cause of pulmonary vascular remodelling in hypoxia‐induced pulmonary hypertension (HPH). However, its underlying ...mechanism has not been well elucidated. Connexin 43 (Cx43) plays crucial roles in vascular smooth muscle cell proliferation in various cardiovascular diseases. Here, the male Sprague‐Dawley (SD) rats were exposed to hypoxia (10% O2) for 21 days to induce rat HPH model. PASMCs were treated with CoCl2 (200 µM) for 24 h to establish the HPH cell model. It was found that hypoxia up‐regulated the expression of Cx43 and phosphorylation of Cx43 at Ser 368 in rat pulmonary arteries and PASMCs, and stimulated the proliferation and migration of PASMCs. HIF‐1α inhibitor echinomycin attenuated the CoCl2‐induced Cx43 expression and phosphorylation of Cx43 at Ser 368 in PASMCs. The interaction between HIF‐1α and Cx43 promotor was also identified using chromatin immunoprecipitation assay. Moreover, Cx43 specific blocker (37,43Gap27) or knockdown of Cx43 efficiently alleviated the proliferation and migration of PASMCs under chemically induced hypoxia. Therefore, the results above suggest that HIF‐1α, as an upstream regulator, promotes the expression of Cx43, and the HIF‐1α/Cx43 axis regulates the proliferation and migration of PASMCs in HPH.
Aqueous Zn–iodine (Zn–I2) batteries have been regarded as a promising energy‐storage system owing to their high energy/power density, safety, and cost‐effectiveness. However, the polyiodide shuttling ...results in serious active mass loss and Zn corrosion, which limits the cycling life of Zn–I2 batteries. Inspired by the chromogenic reaction between starch and iodine, a structure confinement strategy is proposed to suppress polyiodide shuttling in Zn–I2 batteries by hiring starch, due to its unique double‐helix structure. In situ Raman spectroscopy demonstrates an I5−‐dominated I−/I2 conversion mechanism when using starch. The I5− presents a much stronger bonding with starch than I3−, inhibiting the polyiodide shuttling in Zn–I2 batteries, which is confirmed by in situ ultraviolet–visible spectra. Consequently, a highly reversible Zn–I2 battery with high Coulombic efficiency (≈100% at 0.2 A g−1) and ultralong cycling stability (>50 000 cycles) is realized. Simultaneously, the Zn corrosion triggered by polyiodide is effectively inhibited owing to the desirable shuttling‐suppression by the starch, as evidenced by X‐ray photoelectron spectroscopy analysis. This work provides a new understanding of the failure mechanism of Zn–I2 batteries and proposes a cheap but effective strategy to realize high‐cyclability Zn–I2 batteries.
Inspired by the significant chromogenic reaction between starch and iodine, the shuttle effect of Zn–I2 batteries is effectively addressed by using starch, which strongly anchors polyiodide anions due to its unique double‐helix structure. Benefiting from this structure confinement, a Coulombic efficiency of almost 100% and an ultralong life of 50 000 cycles are realized in Zn–I2 batteries.
Defects have been found to enhance the electrocatalytic performance of NiFe‐LDH for oxygen evolution reaction (OER). Nevertheless, their specific configuration and the role played in regulating the ...surface reconstruction of electrocatalysts remain ambiguous. Herein, cationic vacancy defects are generated via aprotic‐solvent‐solvation‐induced leaking of metal cations from NiFe‐LDH nanosheets. DFT calculation and in situ Raman spectroscopic observation both reveal that the as‐generated cationic vacancy defects tend to exist as VM (M=Ni/Fe); under increasing applied voltage, they tend to assume the configuration VMOH, and eventually transform into VMOH‐H which is the most active yet most difficult to form thermodynamically. Meanwhile, with increasing voltage the surface crystalline Ni(OH)x in the NiFe‐LDH is gradually converted into disordered status; under sufficiently high voltage when oxygen bubbles start to evolve, local NiOOH species become appearing, which is the residual product from the formation of vacancy VMOH‐H. Thus, we demonstrate that the cationic defects evolve along with increasing applied voltage (VM → VMOH → VMOH‐H), and reveal the essential motif for the surface restructuration process of NiFe‐LDH (crystalline Ni(OH)x → disordered Ni(OH)x → NiOOH). Our work provides insight into defect‐induced surface restructuration behaviors of NiFe‐LDH as a typical precatalyst for efficient OER electrocatalysis.
Along with increasing voltage during the OER process, the structural evolution of cationic defects within NiFe‐LDH, where the simple vacancy VM changes to VMOH and then to the most reactive VMOH‐H, and the surface restructuration, where surface crystalline Ni(OH)x is converted to disordered Ni(OH)x and then to the surface local NiOOH species, are voltage‐regulated concurrent events defining the eventual catalytic performance of the precatalyst.
Summary
The productivity of species‐diverse plant assemblages strongly depends on the temporal dynamics of nutrient uptake by competing neighbouring plants. Our understanding, however, of how rates ...of nitrogen (N), phosphorous (P) and potassium (K) uptake might change through time between neighbouring plant species under field conditions is still very limited.
Here, we specifically measure the temporal trajectories of N, P and K uptake by staple food plants such as wheat (Triticum aestivum L.), barley (Hordeum vulgare L.) and maize (Zea mays L.) when growing either in monocultures or in intercropping systems. We ask how (i) plant species combinations, (ii) N fertilization and (iii) film mulching might affect key indexes of N, P and K uptake over time. We fit logistic models to characterize the nutrient uptake trajectories.
Maximum cumulative N, P and K uptake (kg ha−1) by wheat and barley were significantly greater in wheat–maize or barley–maize intercropping systems than in wheat or barley monocultures. Cumulative nutrient uptake by intercropped maize (either with wheat or with barley) was reduced by interspecific competition at early growth stages, but it increased rapidly after wheat and barley were harvested. Maximum cumulative N and P (but not K) uptake by intercropped maize were significantly higher than the uptake by monoculture maize, particularly when N fertilizer or film mulching was applied.
Intercropping induced a significant temporal niche differentiation in maximum daily nutrient uptake rates (kg ha−1 day−1) between intercropped species. Fertilization had much stronger effects on maximum cumulative nutrient uptake of maize than that of wheat and barley. Mulching significantly increased the maximum cumulative nutrient uptake of maize and advanced the time to reach its maximum daily P and K uptake rates.
Our study provides evidence of an important temporal niche differentiation mechanism (‘temporal complementarity’) in nutrient uptake rates between neighbouring plant species. A better understanding of temporal trajectories of interspecific nutrient uptake rates remains crucial if we want to maximize the nutrient‐use efficiency and sustain overyielding (i.e. high food production) in plant species‐diverse systems such as intercropping.
Lay Summary
The main advancements of the Beijing Climate Center (BCC) climate system model from
phase 5 of the Coupled Model Intercomparison Project (CMIP5) to phase
6 (CMIP6) are presented, in terms of physical ...parameterizations and model
performance. BCC-CSM1.1 and BCC-CSM1.1m are the two models involved in CMIP5,
whereas BCC-CSM2-MR, BCC-CSM2-HR, and BCC-ESM1.0 are the three models configured for
CMIP6. Historical simulations from 1851 to 2014 from BCC-CSM2-MR (CMIP6) and
from 1851 to 2005 from BCC-CSM1.1m (CMIP5) are used for models assessment.
The evaluation matrices include the following: (a) the energy budget at
top-of-atmosphere; (b) surface air temperature, precipitation, and atmospheric circulation for
the global and East Asia regions; (c) the sea surface temperature (SST) in the
tropical Pacific; (d) sea-ice extent and thickness and Atlantic Meridional
Overturning Circulation (AMOC); and (e) climate variations at different timescales, such as the global warming trend in the 20th century, the stratospheric
quasi-biennial oscillation (QBO), the Madden–Julian Oscillation (MJO), and the diurnal
cycle of precipitation. Compared with BCC-CSM1.1m, BCC-CSM2-MR shows
significant improvements in many aspects including the tropospheric air
temperature and circulation at global and regional scales in East Asia and
climate variability at different timescales, such as the QBO, the MJO, the diurnal cycle
of precipitation, interannual variations of SST in the equatorial Pacific,
and the long-term trend of surface air temperature.
Flexible transparent electrodes (FTEs) with an embedded metal mesh are considered a promising alternative to traditional indium tin oxide (ITO) due to their excellent photoelectric performance, ...surface roughness, and mechanical and environmental stability. However, great challenges remain for achieving simple, cost‐effective, and environmentally friendly manufacturing of high‐performance FTEs with embedded metal mesh. Herein, a maskless, templateless, and plating‐free fabrication technique is proposed for FTEs with embedded silver mesh by combining an electric‐field‐driven (EFD) microscale 3D printing technique and a newly developed hybrid hot‐embossing process. The final fabricated FTE exhibits superior optoelectronic properties with a transmittance of 85.79%, a sheet resistance of 0.75 Ω sq−1, a smooth surface of silver mesh (Ra ≈ 18.8 nm) without any polishing treatment, and remarkable mechanical stability and environmental adaptability with a negligible increase in sheet resistance under diverse cyclic tests and harsh working conditions (1000 bending cycles, 80 adhesion tests, 120 scratch tests, 100 min ultrasonic test, and 72 h chemical attack). The practical viability of this FTE is successfully demonstrated with a flexible transparent heater applied to deicing. The technique proposed offers a promising fabrication strategy with a cost‐effective and environmentally friendly process for high‐performance FTE.
A maskless, templateless, and plating‐free fabrication method for high‐performance flexible transparent electrodes with embedded silver mesh is proposed by combining an electric‐field‐driven microscale 3D printing technique and a hybrid hot‐embossing process. The flexible transparent electrode with embedded silver mesh exhibits excellent photoelectric properties, remarkable mechanical stability, and environmental adaptability.
Transparent glass with metal mesh is considered a promising strategy for high performance transparent glass heaters (TGHs). However, the realization of simple, low‐cost manufacture of high ...performance TGHs still faces great challenges. Here, a technique for the fabrication of high performance TGHs is proposed using liquid sacrificial substrate electric‐field‐driven (LS‐EFD) microscale 3D printing of thick film silver paste. The liquid sacrificial substrate not only significantly improves the aspect ratio (AR) of silver mesh, but also plays a positive role in printing stability. The fabricated TGHs with a line width of 35 µm, thickness of 12.3 µm, and pitch of 1000 µm exhibit a desirable optoelectronic performance with sheet resistance (Rs) of 0.195 Ω sq−1 and transmittance (T) of 88.97%. A successful deicing test showcases the feasibility and practicality of the manufactured TGHs. Moreover, an interface evaporator is developed for the coordination of photothermal and electrothermal systems based on the high performance TGHs. The vapor generation rate of the device reaches 10.69 kg m−2 h−1 with a voltage of 2 V. The proposed technique is a promising strategy for the cost‐effective and simple fabrication of high performance TGHs.
An inexpensive fabrication method for high performance transparent glass heaters (TGHs) by liquid sacrificial substrate electric‐field‐driven microscale 3D printing is presented. The manufactured TGHs exhibit excellent optoelectronic properties remarkable mechanical stability and environmental adaptability.
4D printing is an emerging fabrication technology that enables 3D printed structures to change configuration over “time” in response to an environmental stimulus. Compared with other soft active ...materials used for 4D printing, shape‐memory polymers (SMPs) have higher stiffness, and are compatible with various 3D printing technologies. Among them, ultraviolet (UV)‐curable SMPs are compatible with Digital Light Processing (DLP)‐based 3D printing to fabricate SMP‐based structures with complex geometry and high‐resolution. However, UV‐curable SMPs have limitations in terms of mechanical performance, which significantly constrains their application ranges. Here, a mechanically robust and UV‐curable SMP system is reported, which is highly deformable, fatigue resistant, and compatible with DLP‐based 3D printing, to fabricate high‐resolution (up to 2 µm), highly complex 3D structures that exhibit large shape change (up to 1240%) upon heating. More importantly, the developed SMP system exhibits excellent fatigue resistance and can be repeatedly loaded more than 10 000 times. The development of the mechanically robust and UV‐curable SMPs significantly improves the mechanical performance of the SMP‐based 4D printing structures, which allows them to be applied to engineering applications such as aerospace, smart furniture, and soft robots.
A mechanically robust and UV‐curable shape‐memory polymer (SMP) system can be stretched by up to 1240% of its original length and is compatible with Digital Light Processing (DLP)‐based high‐resolution 3D printing technology (up to 2 µm). The high deformability and fatigue resistance (more than 10 000 cycles loading–unloading) make the SMP an ideal 4D printing material for engineering applications.
Plant diversity in experimental systems often enhances ecosystem productivity, but the mechanisms causing this overyielding are only partly understood. Intercropping faba beans (Vicia faba L.) and ...maize (Zea mays L.) result in overyielding and also, enhanced nodulation by faba beans. By using permeable and impermeable root barriers in a 2-y field experiment, we show that root–root interactions between faba bean and maize significantly increase both nodulation and symbiotic N₂ fixation in intercropped faba bean. Furthermore, root exudates from maize promote faba bean nodulation, whereas root exudates from wheat and barley do not. Thus, a decline of soil nitrate concentrations caused by intercropped cereals is not the sole mechanism for maize promoting faba bean nodulation. Intercropped maize also caused a twofold increase in exudation of flavonoids (signaling compounds for rhizobia) in the systems. Roots of faba bean treated with maize root exudates exhibited an immediate 11-fold increase in the expression of chalcone–flavanone isomerase (involved in flavonoid synthesis) gene together with a significantly increased expression of genes mediating nodulation and auxin response. After 35 d, faba beans treated with maize root exudate continued to show up-regulation of key nodulation genes, such as early nodulin 93 (ENOD93), and promoted nitrogen fixation. Our results reveal a mechanism for how intercropped maize promotes nitrogen fixation of faba bean, where maize root exudates promote flavonoid synthesis in faba bean, increase nodulation, and stimulate nitrogen fixation after enhanced gene expression. These results indicate facilitative root–root interactions and provide a mechanism for a positive relationship between species diversity and ecosystem productivity.
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