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Extreme drought and intensification of land use pose substantial threats to ecosystem stability. However, existing studies that assess ecosystem stability focus primarily on the stability of aboveground net primary productivity (ANPP), while the stability of belowground net primary productivity (BNPP) is often not considered.Here, we examined the response patterns and drivers of ANPP stability and BNPP stability in an alpine meadow to drought and clipping (simulating grazing and mowing) by the implementation of five levels of simulated precipitation (1/12, 1/4, 1/2, 3/4 and ambient precipitation) and clipping (unclipped vs. clipped) treatments over 7 years (2016–2022).The results showed that extreme drought decreased ANPP stability, while moderate drought increased BNPP stability and net primary productivity stability. The findings highlight the importance of jointly considering above‐ and belowground processes when evaluating ecosystem stability. Moreover, clipping did not have an impact on ANPP stability but reduced BNPP stability, and clipping differentially affected the stability of ANPP and BNPP in response to extreme drought. Furthermore, ANPP stability was largely determined by species temporal asynchrony rather than richness, whereas dominant species stability strongly contributed to the variation in BNPP stability of this alpine meadow faced with drought and clipping.Synthesis: In general, these results provide experimental evidence for the decoupling of the responses of above‐ and belowground productivity stability to extreme drought and clipping. Our findings indicate that aboveground responses should not be used as the sole indicator of the whole ecosystem consequences of extreme drought and disturbance factors such as grazing or mowing, emphasizing the need to evaluate ecosystem stability from a whole ecosystem perspective. [ABSTRACT FROM AUTHOR]

ABSTRACT The underlying assembly processes of surface microbial communities are crucial for host plants and ecosystem functions. However, the relative importance of stochastic and deterministic processes in shaping epiphytic microbes remains poorly understood in both the phyllosphere and rhizosphere. Here, we compared the spatial variations in epiphytic microbial communities of two dominant grasses along a 1400 km transect on the Tibetan Plateau and assessed the assembly processes between the phyllosphere and rhizosphere. We found significant variations in epiphytic microbial community compositions between plant compartments and host species. Stochastic processes (drift and homogenizing dispersal) predominantly shaped microbial communities in both the phyllosphere and rhizosphere, with a greater contribution of stochastic processes in the phyllosphere. As environmental heterogeneity intensified, we found a transition from stochasticity to determinism in affecting the microbial assembly. This transition to homogeneous or variable selection depended on plant compartments and host species. Our study is among the first to compare the contribution of stochastic versus deterministic processes to epiphytic community assembly between the phyllosphere and rhizosphere on the Tibetan Plateau. These findings advance our knowledge of epiphytic microbial assembly and disentangle how host plants exploit the microbiome for improved performance and functioning in stressful alpine ecosystems. [ABSTRACT FROM AUTHOR]

Drained wetlands are thought to be carbon (C) source hotspots, and rewetting is advocated to restore C storage in drained wetlands for climate change mitigation. However, current assessments of wetland C balance mainly focus on vertical fluxes between the land and atmosphere, frequently neglecting lateral carbon fluxes and land‐use effects. Here, we conduct a global synthesis of 893 annual net ecosystem C balance (NECB) measures that include net ecosystem exchange of CO2, along with C input via manure fertilization, and C removal through biomass harvest or hydrological exports of dissolved organic and inorganic carbon, across wetlands of different status and land uses. We find that elevating water table substantially reduces net ecosystem C losses, with the annual NECB decreasing from 2579 (95% interval: 1976 to 3214) kg C ha−1 year−1 in drained wetlands to −422 (−658 to −176) kg C ha−1 year−1 in natural wetlands, and to −934 (−1532 to −399) kg C ha−1 year−1 in rewetted wetlands globally. Climate, land‐use history, and time since water table changes introduce variabilities, with drainage for (sub)tropical agriculture or forestry uses showing high annual C losses, while the net C losses from drained wetlands can continue to affect soil C pools for several decades. Rewetting all types of drained wetlands is needed, particularly for those formerly agriculture‐used (sub)tropical wetlands where net ecosystem C losses can be largely reduced. Our findings suggest that elevating water table is an important initiative to reduce C losses in degraded wetlands, which could contribute to policy decisions for managing wetlands to enhance their C sequestration. [ABSTRACT FROM AUTHOR]

In this study, based on the OI135.6 nm night airglow data of the FY‐3D Ionospheric Photometer (IPM) during the 2018–2021 geomagnetically quiet period, the global wavenumber 4 longitudinal structure of the equatorial ionization anomaly (EIA) at 2:00 local time was discovered, and the component of the wavenumber 4 was extracted from these structures. Compared with the OI135.6 nm night airglow data of the Special Sensor Ultraviolet Spectrographic Imager (SSUSI) F18 during 2011–2014, there were significant differences in the variation pattern of the relative amplitude of the two versus solar activity and the seasonal variation in the proportion of the component of the wavenumber 4. Based on the neutral wind speed observation results of the Michelson Interferometer for Global High‐Resolution Thermospheric Imaging on board the Ionospheric Connection Explorer (ICON) from 2020 to 2021, the longitudinal structures of the 4 ionospheric waves after midnight are related to the cross‐equatorial meridional wind. We believe that the wavenumber 4 longitudinal structures after midnight originate from the semidiurnal eastward‐propagating with zonal wavenumber 2 (SE2) nonmigrating tide in the cross‐equatorial neutral wind rather than the diurnal eastward‐propagating with zonal wavenumber 3 (DE3) nonmigrating tide in from the zonal wind, which modulates the daytime wavenumber 4 longitudinal structures. Plain Language Summary: The longitudinal structures of EIA have been extensively studied by using satellite data. However, there are few observations and studies, due to the weak ionosphere near midnight. In this paper, we studied the longitudinal structures of EIA at 02:00 local time during geomagnetically quiet period, benefitted from the satellite orbits and high sensitivity of FY‐3D IPM. We found that the wavenumber 4 longitudinal structures of EIA still exist at 02:00 local time and are obvious at equinoxes. Compared with SSUSI F18 data, FY‐3D IPM data showed different characteristics of wavenumber 4 component of EIA longitudinal structures. Because of the different local time of data between SSUSI F18 and FY‐3D IPM, we consider that the longitudinal wavenumber 4 structures of EIA after midnight originated from the cross‐equatorial neutral wind rather than the electric field modulated by zonal neutral wind in daytime. Key Points: The wavenumber 4 longitudinal structures of equatorial ionization anomaly (EIA) still exist after midnight and are more obvious at equinoxesThe wavenumber 4 component of EIA after midnight is positively correlated with the solar activity levelThe origin of the wavenumber 4 longitudinal structures of EIA after midnight is the modulation of the cross‐equatorial neutral wind [ABSTRACT FROM AUTHOR]

The development of stable and efficient electrocatalysts for overall freshwater/seawater water‐splitting has received significant attention. In this study, the fabrication and electrocatalytic properties of phosphorus‐enriched PtP2 dispersed on CoP (PtP2/CoP) for HER and OER in both alkaline fresh/seawater media are described. Physical characterization and density functional theory calculations reveal that strong electronic interfacial interactions between PtP2 and CoP optimized the reaction kinetics by regulating the adsorption/desorption of intermediates and the cleavage of reactants. Additionally, operando electrochemical impedance spectroscopy reveals that PtP2/CoP significantly decreased phase angle with increasing applied potential compared with CoP, demonstrating that the construction of heterostructure provides a faster charge transfer on the surface and in the inner layer. Notably, the catalyst only requires overpotentials of 101 and 298 mV to achieve a benchmark of 100 mA cm−2 in alkaline freshwater for HER and OER. Moreover, the prepared catalyst featured overpotentials of 108 and 330 mV in an alkaline seawater electrolyte. Furthermore, a stable and high‐efficiency water electrolysis operation can be achieved using PtP2/CoP as both the anode and cathode (1.63 V@100 mA cm−2) coupled with satisfactory durability. This finding provides a deeper comprehension of the interaction of Pt‐less compounds and matrix in electrocatalysis for bifunctional electrocatalysts. [ABSTRACT FROM AUTHOR]

The grounding circulation current of the sheath and armour of single‐core AC submarine cables is high during operation, which can easily cause insulation damage and faults. Traditional methods that only monitor the amplitude of grounding circulation current make it difficult to detect defects in the cables, so further research is needed on the mathematical mechanism and detection methods of grounding circulation current. A mathematical model for the capacitance and impedance coupling of a single‐core submarine cable was established, and the influence of factors such as active power, length of armour stripping section, armour resistivity, armour magnetic permeability and grounding resistance on the grounding circulation current was analysed. A method for identifying abnormal grounding circulation current of submarine cables based on the combination of amplitude and phase was proposed. [ABSTRACT FROM AUTHOR]

Determination of tipping points in nitrogen (N) isotope (δ15N) natural abundance, especially soil δ15N, with increasing aridity, is critical for estimating N‐cycling dynamics and N limitation in terrestrial ecosystems. However, whether there are linear or nonlinear responses of soil δ15N to increases in aridity and if these responses correspond well with soil N cycling remains largely unknown. In this study, we investigated soil δ15N and soil N‐cycling characteristics in both topsoil and subsoil layers along a drought gradient across a 3000‐km transect of drylands on the Qinghai–Tibetan Plateau. We found that the effect of increasing aridity on soil δ15N values shifted from negative to positive with thresholds at aridity index (AI) = 0.27 and 0.29 for the topsoil and subsoil, respectively, although soil N pools and N transformation rates linearly decreased with increasing aridity in both soil layers. Furthermore, we identified markedly different correlations between soil δ15N and soil N‐cycling traits above and below the AI thresholds (0.27 and 0.29 for topsoil and subsoil, respectively). Specifically, in wetter regions, soil δ15N positively correlated with most soil N‐cycling traits, suggesting that high soil δ15N may result from the "openness" of soil N cycling. Conversely, in drier regions, soil δ15N showed insignificant relationships with soil N‐cycling traits and correlated well with factors, such as soil‐available phosphorus and foliage δ15N, demonstrating that pathways other than typical soil N cycling may dominate soil δ15N under drier conditions. Overall, these results highlight that different ecosystem N‐cycling processes may drive soil δ15N along the aridity gradient, broadening our understanding of N cycling as indicated by soil δ15N under changing drought regimes. The aridity threshold of soil δ15N should be considered in terrestrial N‐cycling models when incorporating 15N isotope signals to predict N cycling and availability under climatic dryness. [ABSTRACT FROM AUTHOR]

Sodium/potassium‐ion batteries (NIBs and KIBs) are considered the most promising candidates for lithium‐ion batteries in energy storage fields. Tin sulfide (SnS2) is regarded as an attractive negative candidate for NIBs and KIBs thanks to its superior power density, high‐rate performance and natural richness. Nevertheless, the slow dynamics, the enormous volume change and the decomposition of polysulfide intermediates limit its practical application. Herein, microcubes SnS2 were prepared through sacrificial MnCO3 template‐assisted and a facile solvothermal reaction strategy and their performance was investigated in Na and K‐based cells. The unique hollow cubic structure and well‐confined SnS2 nanosheets play an important role in Na+/K+ rapid kinetic and alleviating volume change. The effect of the carbon additives (Super P/C65) on the electrochemical properties were investigated thoroughly. The in operando and ex‐situ characterization provide a piece of direct evidence to clarify the storage mechanism of such conversion‐alloying type negative electrode materials. [ABSTRACT FROM AUTHOR]

The relationship between biodiversity and ecosystem functioning has mainly focused on plant communities, with comparably little known about soil microbial‐driven ecosystem functions. Climate change severely threatens soil microbial roles, but how soil microbial communities determine soil multifunctionality under climate change is poorly understood.Here, we evaluated the effects of diverse bacterial and fungal properties, including microbial gene abundance, diversity and network complexity, on soil multifunctionality (nine soil functions) across a 3000 km transect along a natural precipitation gradient in Tibetan alpine grasslands. Variation partitioning analyses were performed to disentangle the relative importance of bacterial and fungal properties to the variation of soil multifunctionality. Moreover, structural equation modelling was adopted to explore the influencing pathways of precipitation‐induced changes in plant and edaphic factors to soil microbial properties and, consequently, soil multifunctionality.Soil multifunctionality was positively associated with bacterial and fungal gene abundance, diversity and network complexity. Microbial gene abundance was the more important driver influencing soil multifunctionality than microbial diversity and network complexity. In addition, microbial gene abundance was mainly determined by precipitation‐induced changes in soil pH. Meanwhile, the effects of bacterial properties on soil multifunctionality were much larger than those of fungi. Soil multifunctionality was closely associated with different bacterial (cellulolysis, ligninolysis, nitrogen reduction, denitrification and nitrate fixation etc.) and fungal (soil saprotrophs, arbuscular mycorrhizal and plant pathogens etc.) functional guilds, which exert vital regulations on an array of soil biogeochemical cycling processes.Our results provide the large‐scale evidence of the relative contribution of soil microbial gene abundance, diversity and network complexity to the variation of soil multifunctionality in alpine grasslands with changing precipitation, which is pivotal for understanding microbial roles in modulating and predicting soil multifunctionality under future precipitation changes. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

This article explores the thermal acclimation of ecosystem processes to climate warming, with a focus on plant phenology and photosynthesis. The study finds that plant phenology responses to warming level off over time, suggesting acclimation to higher temperatures. The article also discusses the thermal optimality and acclimation of ecosystem carbon cycling, indicating that previous interpretations may have overestimated the positive feedbacks between climate change and the carbon cycle. The rates of response to warming may vary among different life forms, with herbaceous species potentially adapting more rapidly than woody plants. The study suggests that other limiting factors, such as soil water and nutrient availability, may become more important and constrain phenological responses to rising temperatures over longer periods. Overall, the findings suggest that shifts in plant phenology and ecosystem processes may be less significant than anticipated as climate warming continues. The article emphasizes the need for further research, particularly whole-ecosystem field experiments that include both above- and belowground warming, to better understand thermal acclimation and its effects on different organisms and ecological processes. These experiments could provide insights into the pace and factors influencing acclimation, as well as the long-term effects on species composition and soil conditions. The results could also help improve models and reduce uncertainties in predicting the response of terrestrial ecosystems to warming. [Extracted from the article]

Regulating the metal‐support interaction of the anchored metal nanoclusters is recognized as valid approach to optimize the electrocatalytic performance through tuning the interfacial electronic structure. However, developing novel support and understanding the interfacial electron accumulation on modulating the reaction kinetics are still elusive. Herein, highly‐dispersed Ruthenium (Ru) nanoclusters anchored onto phosphorous doped molybdenum boride (Ru/P‐MoB) is developed through ultrafast microwave‐plasma (60 s) approach. The synthesized Ru/P‐MoB impressively promote the hydrogen evolution with low overpotentials of 34, 45, and 40 mV to drive 10 mA cm−2 in alkaline freshwater, alkaline seawater and acid media. Specially, it presents superior turnover frequency and mass/specific activity relative to Pt/C, Ru/C, and Ru/MoB. Moreover, the anion exchange membrane (AEM) electrolyzer cell based on Ru/P‐MoB can achieve 500 and 1000 mA cm−2 with small voltages of 1.71 and 1.78 V with good durability. Experimental and density functional theoretical (DFT) analysis reveal that the strong metal‐support interactions (Ru─Mo and Ru─P bonds) with generated interfacial electron‐enriched Ru, and then favoring the water‐molecule adsorption/dissociation and optimal H intermediate adsorption free energy. This work provides novel designing avenue to exploit electrocatalysts with outstanding catalytic performance under high current density at practical high‐temperature. [ABSTRACT FROM AUTHOR]

Climate warming, often accompanied by extreme drought events, could have profound effects on both plant community structure and ecosystem functioning. However, how warming interacts with extreme drought to affect community‐ and ecosystem‐level stability remains a largely open question. Using data from a manipulative experiment with three warming treatments in an alpine meadow that experienced one extreme drought event, we investigated how warming modulates resistance and recovery of community structural and ecosystem functional stability in facing with extreme drought. We found warming decreased resistance and recovery of aboveground net primary productivity (ANPP) and structural resistance but increased resistance and recovery of belowground net primary productivity (BNPP), overall net primary productivity (NPP), and structural recovery. The findings highlight the importance of jointly considering above‐ and belowground processes when evaluating ecosystem stability under global warming and extreme climate events. The stability of dominant species, rather than species richness and species asynchrony, was identified as a key predictor of ecosystem functional resistance and recovery, except for BNPP recovery. In addition, structural resistance of common species contributed strongly to the resistance changes in BNPP and NPP. Importantly, community structural resistance and recovery dominated the resistance and recovery of BNPP and NPP, but not for ANPP, suggesting the different mechanisms underlie the maintenance of stability of above‐ versus belowground productivity. This study is among the first to explain that warming modulates ecosystem stability in the face of extreme drought and lay stress on the need to investigate ecological stability at the community level for a more mechanistic understanding of ecosystem stability in response to climate extremes. [ABSTRACT FROM AUTHOR]

Developing green hydrogen energy to power future societies has driven the progress of proton‐exchange membrane water electrolyzers (PEMWE). However, due to the complex anode oxygen evolution reaction (OER) electron transfer process and the strong acidic environment, the most effective catalysts are still Ir‐based nanomaterials. Therefore, exploiting low cost acidic OER catalysts to meet the needs of PEMWE remains a challenging and rewarding task. Herein, hexagonal‐shaped and defect‐rich MnOx/RuO2 heterojunction nanosheets (H/d‐MnOx/RuO2) is designed. The oxygen vacancies and heterogeneous structure enable the H/d‐MnOx/RuO2 catalyst to reach 10 mA cm−2 with only overpotential 178 mV in 0.5 m H2SO4. Density functional theory shows that the oxygen vacancies and heterogeneous interface facilitates the reduction of the adsorption energy of *OOH and the reduction of the energy level of Ru‐Oads, thus suppressing the involvement of lattice oxygen and enhancing the durability. This study provides an effective way to design efficient catalysts for hydrogen production in PEMWE. [ABSTRACT FROM AUTHOR]

Oxygen evolution reaction (OER) remains a bottleneck for electrocatalytic water‐splitting to generate hydrogen. However, the traditional adsorbed evolution mechanism (AEM) possesses sluggish reaction kinetics due to the scaling relationship, while lattice oxygen mechanism (LOM) triggers an unstable structure due to the escaping of lattice oxygen. Herein, a proof‐of‐concept Fe‐Co(OH)2/Fe2O3 heterostructure is put forward, where Fe‐Co(OH)2 following AEM can complete rapidly deprotonation process while Fe2O3 following LOM can trigger O─O coupling step. Combining the theoretical and experimental investigation confirmed that the redistributed space‐charge of Fe‐Co(OH)2/Fe2O3 junction can optimize synergistically adsorbed and lattice oxygen, the coupling mechanism of AEM and LOM can facilitate synchronously the OER activity and stability. As a result, the Fe‐Co(OH)2/Fe2O3 heterostructure shows excellent OER performance with low overpotential of only 219 and 249 mV to reach a current density of 10 and 100 mA cm−2. Specifically, the Fe‐Co(OH)2/Fe2O3 electrocatalyst maintains excellent long‐term stability for 100 h at a large current density of 100 mA cm−2. This work paves an avenue to break through the limit of the conventional OER mechanism. [ABSTRACT FROM AUTHOR]

Aim: Theoretically, woody biomass turnover time (τ) quantified using outflux (i.e. tree mortality) predicts biomass dynamics better than using influx (i.e. productivity). This study aims at using forest inventory data to empirically test the outflux approach and generate a spatially explicit understanding of woody τ in mature forests. We further compared woody τ estimates with dynamic global vegetation models (DGVMs) and with a data assimilation product of C stocks and fluxes—CARDAMOM. Location: Continents. Time Period: Historic from 1951 to 2018. Major Taxa Studied: Trees and forests. Methods: We compared the approaches of using outflux versus influx for estimating woody τ and predicting biomass accumulation rates. We investigated abiotic and biotic drivers of spatial woody τ and generated a spatially explicit map of woody τ at a 0.25‐degree resolution across continents using machine learning. We further examined whether six DGVMs and CARDAMOM generally captured the observational pattern of woody τ. Results: Woody τ quantified by the outflux approach better (with R2 0.4–0.5) predicted the biomass accumulation rates than the influx approach (with R2 0.1–0.4) across continents. We found large spatial variations of woody τ for mature forests, with highest values in temperate forests (98.8 ± 2.6 y) followed by boreal forests (73.9 ± 3.6 y) and tropical forests. The map of woody τ extrapolated from plot data showed higher values in wetter eastern and pacific coast USA, Africa and eastern Amazon. Climate (temperature and aridity index) and vegetation structure (tree density and forest age) were the dominant drivers of woody τ across continents. The highest woody τ in temperate forests was not captured by either DGVMs or CARDAMOM. Main Conclusions: Our study empirically demonstrated the preference of using outflux over influx to estimate woody τ for predicting biomass accumulation rates. The spatially explicit map of woody τ and the underlying drivers provide valuable information to improve the representation of forest demography and carbon turnover processes in DGVMs. [ABSTRACT FROM AUTHOR]

Nowadays, wide‐bandgap (WBG) devices, primarily made from silicon carbide (SiC) and gallium nitride (GaN), are widely applied in power generation, transmission, and conversion. Moreover, the application of WBG devices has had a transformative impact in the field of energy conversion. Compared with Si counterparts, SiC and GaN can remarkably improve the power conversion system efficiency and power density while generating higher electromagnetic interference (EMI) emissions. There are many studies on WBG devices and their behaviour in power systems. However, methods of mitigating EMI/electromagnetic compatibility (EMC) still lack scientific guidance. This article reviews the characteristics of WBG devices, and the significant EMI problems are discussed. Then, the EMI types, EMI causes, and methods of EMI reduction are summarized, and the advantages and disadvantages of these methods are presented as well. Based on the reviewed studies, future research, and the conclusions of this article on EMI/EMC are discussed to help relevant researchers deepen their understanding of the new challenges of EMI brought by the applications of WBG devices, which are useful in engineering. [ABSTRACT FROM AUTHOR]

Background: The outbreak of coronavirus disease 2019 (COVID‐19) caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) has posed a great threat to human health. Some severe COVID‐19 patients still carried detectable levels of SARS‐CoV‐2 even after prolonged intensive care unit treatment. However, the immunological features of these COVID‐19 patients with delayed virus clearance (CDVC) are still unclear. Methods: We retrospectively reviewed the clinical and immunological data of 13 CDVC cases, who were admitted into one hospital in Wuhan from February to April 2020. These data were also compared to those of perished (n = 9) and recovered (n = 52) cases. The expression of the exhaustion marker PD‐1 on circulating T cells of these patients was measured by flow cytometry. Results: High levels of serum interleukin‐6 (IL‐6), IL‐1β, IL‐8, as well as other inflammatory mediators, were seen in CDVC cases. Severe lymphopenia was observed in CDVC patients with the counts of total lymphocytes (0.9 × 109/L), CD4+ T cells (0.35 × 109/L), and CD8+ T cells (0.28 × 109/L) below their corresponding lower limits of normal range. Similar to the perished group, CDVC cases have higher percentages of CD25+Foxp3+ regulatory T cells (Treg) in circulation. Moreover, enhanced expression of the exhaustion marker PD‐1 on CCR7−CD45RA+ effector, CCR7+CD45RA− central memory, and CCR7−CD45RA− effector memory CD4+ and CD8+ T cells were also observed in CDVC cases. Conclusion: CDVC patients still have SARS‐CoV‐2 and these cases manifest with severe clinical symptoms due to persistent inflammation. Augmentation of the frequency of circulating Treg, severe lymphopenia, and functional exhaustion of T cells might lead to inefficient clearance of SARS‐CoV‐2. Therefore, enhancing lymphocyte counts and reversing T‐cell exhaustion might be key methods to boost immune responses and eliminate SARS‐CoV‐2 in CDVC patients. [ABSTRACT FROM AUTHOR]

Liver metastasis is the most fatal event of colon cancer patients. Warburg effect has been long challenged by the fact of upregulated oxidative phosphorylation (OXPHOS), while its mechanism remains unclear. Here, metastasis‐associated antigen 1 (MTA1) is identified as a newly identified adenosine triphosphate (ATP) synthase modulator by interacting with ATP synthase F1 subunit alpha (ATP5A), facilitates colon cancer liver metastasis by driving mitochondrial bioenergetic metabolism reprogramming, enhancing OXPHOS; therefore, modulating ATP synthase activity and downstream mTOR pathways. High‐throughput screening of an anticancer drug shows MTA1 knockout increases the sensitivity of colon cancer to mitochondrial bioenergetic metabolism‐targeted drugs and mTOR inhibitors. Inhibiting ATP5A enhances the sensitivity of liver‐metastasized colon cancer to sirolimus in an MTA1‐dependent manner. The therapeutic effects are verified in xenograft models and clinical cases. This research identifies a new modulator of mitochondrial bioenergetic reprogramming in cancer metastasis and reveals a new mechanism on upregulating mitochondrial OXPHOS as the reversal of Warburg effect in cancer metastasis is orchestrated. [ABSTRACT FROM AUTHOR]

Climate change leads to increasing temperature and more extreme hot and drought events. Ecosystem capability to cope with climate warming depends on vegetation's adjusting pace with temperature change. How environmental stresses impair such a vegetation pace has not been carefully investigated. Here we show that dryness substantially dampens vegetation pace in warm regions to adjust the optimal temperature of gross primary production (GPP) (ToptGPP) in response to change in temperature over space and time. ToptGPP spatially converges to an increase of 1.01°C (95% CI: 0.97, 1.05) per 1°C increase in the yearly maximum temperature (Tmax) across humid or cold sites worldwide (37oS–79oN) but only 0.59°C (95% CI: 0.46, 0.74) per 1°C increase in Tmax across dry and warm sites. ToptGPP temporally changes by 0.81°C (95% CI: 0.75, 0.87) per 1°C interannual variation in Tmax at humid or cold sites and 0.42°C (95% CI: 0.17, 0.66) at dry and warm sites. Regardless of the water limitation, the maximum GPP (GPPmax) similarly increases by 0.23 g C m−2 day−1 per 1°C increase in ToptGPP in either humid or dry areas. Our results indicate that the future climate warming likely stimulates vegetation productivity more substantially in humid than water‐limited regions. [ABSTRACT FROM AUTHOR]

Climate warming and extreme climatic events are threatening ecosystem processes and functions. However, it remains unclear how climate warming changes ecosystem stability in facing extreme rainfall events.Here, we investigated the temporal stability of above‐ground net primary productivity (ANPP) in an alpine meadow via a 5‐year warming experiment, during which two flooding events occurred, in an alpine meadow.We first found that warming significantly increased the temporal stability of ANPP in facing flooding events by increasing resistance to and decreasing recovery from flooding events. Second, we found that warming shifted the plant community structure by increasing the dominance of grasses and reducing species richness and asynchrony. Last, we detected the higher temporal stability of ANPP under warming, which was mainly ascribed to the warming‐induced increase in dominant species stability (Deschampsia caespitosa).Synthesis. These findings indicate that climate warming may mitigate the shock of flooding events on the temporal stability of community productivity via altering plant community structure in alpine grasslands. Our study highlights that to buffer ecosystems from climatic extremes, we should focus on promoting the maintenance or selection of dominant species rather than only focusing on increasing species richness. [ABSTRACT FROM AUTHOR]

The responses of soil nitrogen (N) transformations to climate change are crucial for biome productivity prediction under global change. However, little is known about the responses of soil gross N transformation rates to drought gradient. Along an aridity gradient across the 2700 km transect of drylands on the Qinghai‐Tibetan Plateau, this study measured three main soil gross N transformation rates in both topsoil (0–10 cm) and subsoil (20–30 cm) using the laboratorial 15N labeling. The relevant soil abiotic and biotic variables were also determined. The results showed that gross N mineralization and nitrification rates steeply decreased with increasing aridity when aridity was less than 0.5 but just slightly decreased with increasing aridity when aridity was larger than 0.5 at both soil layers. In topsoil, the decreases of the two gross rates were accompanied by the similar decreased patterns of soil total N content and microbial biomass carbon with increasing aridity (p <.05). In subsoil, although the decreased pattern of soil total N with increasing aridity was still similar to the decreases of the two gross rates (p <.05), microbial biomass carbon did not change (p >.05). Instead, bacteria and ammonia oxidizing archaea abundances decreased with increasing aridity when aridity was larger than 0.5 (p <.05). With an aridity threshold of 0.6, gross N immobilization rate increased with increasing aridity in wetter region (aridity < 0.6) accompanied with an increased bacteria/fungi ratio, but decreased with increasing aridity in drier region (aridity > 0.6) where mineral N and microbial biomass N also decreased at both soil layers (p <.05). This study provided new insight to understand the differential responses of soil N transformation to drought gradient. The threshold responses of the gross N transformation rates to aridity gradient should be noted in biogeochemical models to better predict N cycling and manage land in the context of global change. [ABSTRACT FROM AUTHOR]

Bisphosphonate‐related osteonecrosis of the jaw (BRONJ) is a serious complication that occurs in patients with osteoporosis or metastatic bone cancer treated with bisphosphonate. There is still no effective treatment and prevention strategy for BRONJ. Inorganic nitrate, which is abundant in green vegetables, has been reported to be protective in multiple diseases. To investigate the effects of dietary nitrate on BRONJ‐like lesions in mice, we utilized a well‐established mouse BRONJ model, in which tooth extraction was performed. Specifically, 4 mM sodium nitrate was administered in advance through drinking water to assess the short‐ and long‐term effects on BRONJ. Zoledronate injection could induce severe healing inhibition of the tooth extraction socket, while addition of pretreating dietary nitrate could alleviate the inhibition by reducing monocyte necrosis and inflammatory cytokines production. Mechanistically, nitrate intake increased plasma nitric oxide levels, which attenuated necroptosis of monocytes by downregulating lipid and lipid‐like molecule metabolism via a RIPK3 dependent pathway. Our findings revealed that dietary nitrate could inhibit monocyte necroptosis in BRONJ, regulate the bone immune microenvironment and promote bone remodelling after injury. This study contributes to the understanding of the immunopathogenesis of zoledronate and supports the feasibility of dietary nitrate for the clinical prevention of BRONJ. [ABSTRACT FROM AUTHOR]

Sodium‐ion and potassium‐ion batteries (NIBs and KIBs) are considered promising alternatives to replace lithium‐ion batteries (LIBs) in energy storage applications due to the natural abundance and low cost of Na and K. Nevertheless, a critical challenge is that the large size of Na+/K+ leads to a huge volume change of the hosting material during electrochemical cycling, resulting in rapid capacity decay. Among negative candidates for alkali‐metal‐ion batteries, SnS2 is attractive due to the competitively high specific capacity, low redox potential and high abundance. Porous few‐layer SnS2 nanosheets are in situ grown on reduced graphene oxide, forming a SnS2‐rGO sandwich structure via strong C−O−Sn bonds. This nano‐scaled sandwich structure not only shortens Na+/K+ and electron transport pathways but also accommodates volume expansion, thereby enabling high and stable electrochemical cycling performance of SnS2‐rGO. This work explores the influence of different conductive carbons (Super P and C65) on the SnS2‐rGO electrode. In addition, the effects of the electrolyte additive fluoroethylene carbonate (FEC) on the electrochemical performance in NIBs and KIBs is evaluated. This work provides guidelines for optimized electrode structure design, electrolyte additives and carbon additives for the realization of better NIBs and KIBs. [ABSTRACT FROM AUTHOR]

Microbial necromass is a large and persistent component of soil organic carbon (SOC), especially under croplands. The effects of cropland management on microbial necromass accumulation and its contribution to SOC have been measured in individual studies but have not yet been summarized on the global scale. We conducted a meta‐analysis of 481‐paired measurements from cropland soils to examine the management effects on microbial necromass and identify the optimal conditions for its accumulation. Nitrogen fertilization increased total microbial necromass C by 12%, cover crops by 14%, no or reduced tillage (NT/RT) by 20%, manure by 21%, and straw amendment by 21%. Microbial necromass accumulation was independent of biochar addition. NT/RT and straw amendment increased fungal necromass and its contribution to SOC more than bacterial necromass. Manure increased bacterial necromass higher than fungal, leading to decreased ratio of fungal‐to‐bacterial necromass. Greater microbial necromass increases after straw amendments were common under semi‐arid and in cool climates in soils with pH <8, and were proportional to the amount of straw input. In contrast, NT/RT increased microbial necromass mainly under warm and humid climates. Manure application increased microbial necromass irrespective of soil properties and climate. Management effects were especially strong when applied during medium (3–10 years) to long (10+ years) periods to soils with larger initial SOC contents, but were absent in sandy soils. Close positive links between microbial biomass, necromass and SOC indicate the important role of stabilized microbial products for C accrual. Microbial necromass contribution to SOC increment (accumulation efficiency) under NT/RT, cover crops, manure and straw amendment ranged from 45% to 52%, which was 9%–16% larger than under N fertilization. In summary, long‐term cropland management increases SOC by enhancing microbial necromass accumulation, and optimizing microbial necromass accumulation and its contribution to SOC sequestration requires site‐specific management. [ABSTRACT FROM AUTHOR]

We construct a provincial financial stability index, and use panel vector autoregression to construct a model for empirical testing. We find that local governments' reliance on land grant premiums amplifies the impact on financial stability. In addition, the relationship between the real estate market and the financial system allows real estate price fluctuations to significantly affect market participants, further impacting financial system stability. Finally, in the eastern region, land price fluctuations have a less adverse impact on financial stability, while in other regions, rising commodity real estate prices are the biggest threat to financial stability. [ABSTRACT FROM AUTHOR]

Epiphytic fungi are vital in enhancing their host plant performance and can also cause plant diseases. Generally, phyllosphere fungal community are majorly driven by climate, while rhizosphere fungal community are determined by soil properties and spatial distance. However, the differences in the relative effects of environmental factors on fungal community compositions and network structures remain far from clear between phyllosphere and rhizosphere.In this study, we conducted a large‐scale field survey along a 1400 km transect in the Tibetan Plateau and explored the composition and structure of phyllosphere and rhizosphere fungal communities from two dominant grass species (Leontopodium nanum and Stipa purpurea). L. nanum is widely distributed in relatively wet areas of alpine grasslands but S. purpurea prefers relatively dry areas. The geographical distributions of these two species overlap in the middle of the transectFirst, we found that precipitation was more important than temperature to affect fungal alpha diversity. High precipitation significantly promoted fungal alpha diversity in both phyllosphere and rhizosphere. Second, climate and spatial variables explained more variations in fungal community in the phyllosphere than rhizosphere. Specifically, greater precipitation promoted the relative abundances of pathotrophic fungi in the phyllosphere and rhizosphere, whereas lower precipitation only stimulated the relative abundances of symbiotrophic fungi in the rhizosphere. Third, precipitation had different impacts on phyllosphere and rhizosphere fungal networks between host species. Drought caused lower node number of fungal networks in the phyllosphere and rhizosphere of L. nanum. However, for S. purpurea, drought led to more complex and positive fungal networks in the phyllosphere and rhizosphere. Overall, these results indicated that precipitation caused different fungal community compositions along the transect between phyllosphere and rhizosphere, but consistently shaped their fungal networks.This study is among the first to provide compelling evidence on the large‐scale spatial variations and controlling factors for epiphytic fungal community in alpine grasslands. These new findings help to understand the role of epiphytic fungal community in affecting the functions of alpine grasses to cope with extreme environments. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Temporal stability of ecosystem productivity is important for providing reliable ecosystem services under global changes. Great efforts have been made to explore the response of above‐ground net primary productivity (ANPP) stability to nitrogen (N) enrichment, yet how it affects below‐ground net primary productivity (BNPP) stability remains elusive, which hinders a comprehensive understanding of ecosystem stability from the view of a whole system.Here, using a field manipulative experiment with six N addition rates (0, 2, 4, 8, 16, 32 g N m−2 year−1), we explored the response patterns and drivers of BNPP stability in the topsoil (0–20 cm) and subsoil (20–40 cm) in the alpine meadow.The results showed that BNPP stability at both soil depths showed a unimodal response to increasing N addition rates. Specifically, for both the topsoil and subsoil, low‐level N addition significantly promoted BNPP stability, while high doses of N addition had no significant impact on BNPP stability, suggesting that current low level of N deposition likely benefits the stable provision of below‐ground functioning. Furthermore, dominant species stability and species richness contributed most to the changes in BNPP stability in the topsoil, whereas only dominant species stability was the dominant driver of BNPP stability in the subsoil.This study is among the first to illuminate the main mechanisms underlying the responses of BNPP stability to N enrichment at various soil depths, which will advance our current understanding of N addition effects on below‐ground processes and benefit the sustainable provision of ecosystem functioning in the context of atmospheric N deposition. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Anthropogenic warming and land‐use change are expected to accelerate global soil organic carbon (SOC) losses and change plant species composition and richness. However, how changes in plant composition and species richness mediate SOC responses to climate warming and land‐use change remains poorly understood.Using data from a 7‐year warming and clipping field experiment in an alpine meadow on the Qinghai–Tibetan Plateau, we examined the direct effects of warming and clipping on SOC storage versus their indirect effects mediated by plant functional type and species richness.We found that warming significantly increased SOC storage by 8.1% and clipping decreased it by 6.4%, which was closely correlated with the corresponding response of below‐ground net primary productivity (BNPP). We also found a negative correlation between SOC storage and species richness, which was ascribed to the increased BNPP via enhancing the dominance of grasses and decreasing species richness under warming. The lower SOC storage under clipping was caused by the clipping‐induced decrease in BNPP via weakening the dominance of grasses and increasing species richness.Our findings highlight that the SOC storage in this alpine meadow under climate warming and clipping was primarily governed by BNPP changes, which was mediated by changes in the dominance of grasses and species richness. Overall, our study demonstrates that shifting to the dominance of grasses and changing species richness would benefit soil C sequestration under climate warming, but this positive effect would be dampened by grazing or hay harvest. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Plant and microbial diversity are key to determine ecosystem functioning. Despite the well‐known role of local‐scale α diversity in affecting vegetation biomass, the effects of community heterogeneity (β diversity) of plants and soil microbes on above‐ and belowground biomass (AGB and BGB) across contrasting environments still remain unclear. Here, we conducted a dryness‐gradient transect survey over 3000 km across grasslands on the Tibetan Plateau. We found that plant β diversity was more dominant than α diversity in maintaining higher levels of AGB, while soil fungal β diversity was the key driver in enhancing BGB. However, these positive effects of plant and microbial β diversity on AGB and BGB were strongly weakened by increasing climatic dryness, mainly because higher soil available phosphorus caused by increasing dryness reduced both plant and soil fungal β diversities. Overall, these new findings highlight the critical role of above‐ and belowground β diversity in sustaining grassland biomass, raising our awareness to the ecological risks of large‐scale biotic homogenization under future climate change. [ABSTRACT FROM AUTHOR]

Nanothermometers that can reflect temperature in real‐time are crucial for photothermal therapy. Near‐infrared (NIR) fluorescent probes that conform to Boltzmann distribution will play an important role if they have the above characteristics. Here, the LiLuF4: Nd3+/Yb3+ nanocrystals were designed and synthesized by control, exhibiting multiple bright near‐infrared emission peaks at 925–1080 nm region at 280–360 K under the excitation of an 808 nm laser. The feasibility of being used as a nanothermometer was confirmed by testing the spectral variation with temperature and analysis. [ABSTRACT FROM AUTHOR]

Transition‐metal alloys are currently drawing increasing attention as promising electrocatalysts for the alkaline hydrogen evolution reaction (HER). However, traditional density‐functional‐theory‐derived d‐band theory fails to describe the hydrogen adsorption energy (ΔGH) on hollow sites. Herein, by studying the ΔGH for a series of Ni−M (M=Ti, V, Cr, Mn, Fe, Co, Cu, Zn, Mo, W) bimetallic alloys, an improved d‐band center was provided and a potential NiCu electrocatalyst with a near‐optimal ΔGH was discovered. Moreover, oxygen atoms were introduced into Ni−M (O−NiM) to balance the adsorption/desorption of hydroxyl species. The tailored electrocatalytic sites for water dissociation can synergistically accelerate the multi‐step alkaline HER. The prepared O−NiCu shows the optimum HER activity with a low overpotential of 23 mV at 10 mA cm−2. This work not only broadens the applicability of d‐band theory, but also provides crucial understanding for designing efficient HER electrocatalysts. [ABSTRACT FROM AUTHOR]

Ecological restoration is essential to reverse land degradation worldwide. Most studies have assessed the restoration of ecosystem functions individually, as opposed to a holistic view. Here we developed a network‐based ecosystem multifunctionality (EMF) framework to identify key functions in evaluating EMF restoration. Through synthesizing 293 restoration studies (2900 observations) following cropland abandonment, we found that individual soil functions played different roles in determining the restoration of belowground EMF. Soil carbon, total nitrogen, and phosphatase were key functions to predict the recovery of belowground EMF. On average, abandoned cropland recovered ~19% of EMF during 18 years. The restoration of EMF became larger with longer recovery time and higher humidity index, but lower with increasing soil depth and initial soil carbon. Overall, this study presents a network‐based EMF framework, effectively helping to evaluate the success of ecosystem restoration and identify the key functions. [ABSTRACT FROM AUTHOR]

Martian global dust storms have significant influences on its atmosphere and ionosphere. In this research, the behavior of O2+ ${\mathrm{O}}_{2}^{+}$, CO2+ ${\mathrm{C}\mathrm{O}}_{2}^{+}$, and O+ density profiles during the 2018 global dust storm is studied based on the observations of Neutral Gas and Ion Mass Spectrometer (NGIMS) onboard Mars Atmosphere and Volatile Evolution. The observations show increased CO2+ ${\mathrm{C}\mathrm{O}}_{2}^{+}$ density, decreased O+ density, and relatively stable O2+ ${\mathrm{O}}_{2}^{+}$ density at 170–500 km during the dust storm. Using a photochemical model, we reproduced the behavior of O2+ ${\mathrm{O}}_{2}^{+}$, CO2+ ${\mathrm{C}\mathrm{O}}_{2}^{+}$, and O+ density at 170–200 km during the dust storm based on the behaviors of NGIMS observed neutral density profiles. The behaviors of those neutral and ion density profiles should be the combined effects of the variations of latitude, longitude, season, local time, Solar Zenith Angle (SZA), and the activity of the global dust storm. Two different methods, one based on the Mars Climate Database and another based on a parametric model, are used to remove the effects of latitude, longitude, season, local time, and SZA variations on the neutral atmosphere and ionosphere. Both methods indicate that O2+ ${\mathrm{O}}_{2}^{+}$ density at 170–200 km should increase, rather than stay unchanged under the 2018 global dust storm‐specified effect. Plain Language Summary: The global dust storms have significant influences on the Martian atmosphere and ionosphere. Understanding the behavior of the Martian atmosphere and ionosphere during global dust storms is very important for landing and communicating on Mars. With the help of the Neutral Gas and Ion Mass Spectrometer onboard the Mars Atmosphere and Volatile Evolution spacecraft, we studied the behavior of different ion density profiles in the Martian upper ionosphere (above 160 km) during the 2018 Martian global dust storm. In this way, the expectation of the previous modeling research about the behavior of different ion density profiles at 170–400 km during the global dust storm is confirmed for the first time by observational results. The behavior of ion density profiles at 170–200 km during the dust storm is further reproduced based on the behavior of neutral density profiles, revealing that the ion density profiles below 200 km during dust storms follow the photochemical theory. With the help of two different models, the dust storm‐specified effects on the neutral and ion density profiles at 170–200 km are derived. This combination of observations and simulations could provide a more comprehensive understanding of the behavior of the Martian upper ionosphere and the coupling between the Martian upper ionosphere and neutral upper atmosphere during global dust storms. Key Points: The behavior of the Martian upper ionospheric ion density profiles during the 2018 global dust storm is investigatedAn increased density of CO2+ ${\mathrm{C}\mathrm{O}}_{2}^{+}$, decreased density of O+, and stable density of O2+ ${\mathrm{O}}_{2}^{+}$ at 170–500 km were found during the dust stormThe dust storm‐specific effects on the ion density profiles at 170–200 km are derived [ABSTRACT FROM AUTHOR]

Pronounced nongrowing season warming and changes in soil freeze–thaw (F–T) cycles can dramatically alter net methane (CH4) exchange rates between soils and the atmosphere. However, the magnitudes and drivers of warming impacts on CH4 uptake in different stages of the F–T cycle are poorly understood in cold alpine ecosystems, which have been found to be a net sink of atmospheric CH4. Here, we reported a year‐round ecosystem daily CH4 uptake in an alpine meadow on the Qinghai‐Tibetan Plateau after a 5‐year warming experiment that included a control, a low‐level warming treatment (+2.4℃ at 5 cm soil depth), and a high‐level warming treatment (+4.5℃ at 5 cm soil depth). We found that warming shortened the F–T cycle under the low‐level warming and soils did not freeze under the high‐level warming. Although both warming treatments increased the mean CH4 uptake rate, only the high‐level warming significantly increased annual CH4 uptake compared to the control. The warming‐induced stimulation of CH4 uptake mainly occurred in the cold season, which was mostly during spring thaw under low‐level warming and during the frozen winter under high‐level warming due to a longer period with thawed soil. We also found that warming significantly stimulated daily CH4 uptake mainly by reducing near‐surface soil water content in the warm season, whereas both soil water content and temperature controlled daily CH4 uptake in different ways during the autumn freeze, frozen winter, and spring thaw periods of the control. Our study revealed a strong warming effect on CH4 uptake during the entire F–T cycle in the alpine meadow, especially the unfrozen winter. Our results also suggested the important roles of soil pH, available phosphorus, and methanotroph abundance in regulating annual CH4 uptake in response to warming, which should be incorporated into biogeochemical models for accurately forecasting CH4 fluxes under future climate scenarios. [ABSTRACT FROM AUTHOR]

The accurate prediction of ionospheric Total Electron Content (TEC) is important for global navigation satellite systems (GNSS), satellite communications and other space communications applications. In this study, a prediction model of global IGS‐TEC maps are established based on testing several different long short‐term memory (LSTM) network (LSTM)‐based algorithms to explore a direction that can effectively alleviate the increasing error with prediction time. We find that a Multi‐step auxiliary algorithm based prediction model performs best. It can effectively predict the global ionospheric IGS‐TEC in the next 6 days (the mean absolute deviation (MAD) and root mean square error (RMSE) are 2.485 and 3.511 TECU, respectively) compared to the IRI (the MAD and RMSE are 4.248 and 5.593 TECU). The analyses of four geomagnetic storm events are completely separate from the time range of the training set, so as to further validate the performance of the model. The International Reference Ionosphere model is used as a reference for the performance of our predictive model, and a rotated persistence is estimated by time‐shift algorithm of IGS‐TEC. The result suggests that the Multi‐step auxiliary prediction model has a good generalization performance and can have a relatively good stability and low error during a geomagnetic storm and quiet time. Plain Language Summary: The prediction of global Total Electron Content map is very important for the accuracy of global navigation satellite systems based global positioning system, satellite communications and other space communications applications. As is well known to all, the prediction accuracy usually decrease significantly with the increasing of the prediction time. In order to solve this issue, four different long short‐term memory‐based algorithms are tested to explore a direction that can effectively alleviate the increasing error with prediction time. The result shows that Multi‐step auxiliary prediction model can effectively alleviate the increasing error with prediction time. Moreover, it has a good generalization performance and can have a relatively good stability and low error during a geomagnetic storm. Key Points: Multi‐step auxiliary predictionmodel can effectively alleviate the increasing error with prediction timeMulti‐step auxiliary prediction model can predict international global navigation satellite systems service‐total electron content (TEC) map of next 6 days, and the mean absolute deviation and root mean square error are 2.485 and 3.511 TECU, respectivelyMulti‐step auxiliary prediction model has a good generalization performance and low error during a geomagnetic storm [ABSTRACT FROM AUTHOR]

The denitrification process profoundly affects soil nitrogen (N) availability and generates its byproduct, nitrous oxide, as a potent greenhouse gas. There are large uncertainties in predicting global denitrification because its controlling factors remain elusive. In this study, we compiled 4301 observations of denitrification rates across a variety of terrestrial ecosystems from 214 papers published in the literature. The averaged denitrification rate was 3516.3 ± 91.1 µg N kg−1 soil day−1. The highest denitrification rate was 4242.3 ± 152.3 µg N kg−1 soil day−1 under humid subtropical climates, and the lowest was 965.8 ± 150.4 µg N kg−1 under dry climates. The denitrification rate increased with temperature, precipitation, soil carbon and N contents, as well as microbial biomass carbon and N, but decreased with soil clay contents. The variables related to soil N contents (e.g., nitrate, ammonium, and total N) explained the variation of denitrification more than climatic and edaphic variables (e.g., mean annual temperature (MAT), soil moisture, soil pH, and clay content) according to structural equation models. Soil microbial biomass carbon, which was influenced by soil nitrate, ammonium, and total N, also strongly influenced denitrification at a global scale. Collectively, soil N contents, microbial biomass, pH, texture, moisture, and MAT accounted for 60% of the variation in global denitrification rates. The findings suggest that soil N contents and microbial biomass are strong predictors of denitrification at the global scale. [ABSTRACT FROM AUTHOR]

Objectives: Evidences have suggested that the metabolic function is the key regulator to the fate of MSCs, but its function in senescence of MSC and the underlying mechanism is unclear. Therefore, the purpose of this study was to investigate the metabolic activity of MSCs and its possible mechanism during aging. Materials and Methods: We used the Seahorse XF24 Analyzer to understand OCR and ECAR in BMSCs and used RT‐PCR to analyze the gene expression of mitochondrial biogenesis and key enzymes in glycolysis. We analyzed BMSC mitochondrial activity by MitoTracker Deep Red and JC‐1 staining, and detected NAD+/NADH ratio and ATP levels in BMSCs. Microarray and proteomic analyses were performed to detect differentially expressed genes and proteins in BMSCs. The impact of aging on BMSCs through mitochondrial electron transport chain (ETC) was evaluated by Rotenone and Coenzyme Q10. Results: Our results demonstrated that the oxidative phosphorylation and glycolytic activity of BMSCs in aged mice were significantly decreased when compared with young mice. BMSCs in aged mice had lower mitochondrial membrane potential, NAD+/NADH ratio, and ATP production than young mice. FABP4 may play a key role in BMSC senescence caused by fatty acid metabolism disorders. Conclusions: Taken together, our results indicated the dysfunction of the metabolic activity of BMSCs in aged mice, which would play the important role in the impaired biological properties. Therefore, the regulation of metabolic activity may be a potential therapeutic target for enhancing the regenerative functions of BMSCs. [ABSTRACT FROM AUTHOR]

To reach a closed‐loop material system and meet the urgent requirement of sustainable energy storage technologies, it is essential to incorporate efficient waste management into designing new energy storage materials. Here, a "two birds with one stone" strategy to transform rusty iron products into Prussian blue as high‐performance cathode materials, and recover the rusty iron products to their original status, is reported. Owing to the high crystalline and Na+ content, the rusty iron derived Prussian blue shows a high specific capacity of 145 mAh g−1 and excellent cycling stability over 3500 cycles. Through the in situ X‐ray diffraction and in situ Raman spectra, it is found that the impressive ion storage capability and stability are strongly related to the suppressed structure distortion during the charge/discharge process. The ion migration mechanism and the possibility to serve as a universal host for other kinds of ions are further illuminated by density functional theory calculations. This work provides a new strategy for recycling wasted materials into high value‐added materials for sustainable battery systems, and is adaptable in the nanomedicine, catalysis, sensors, and gas storage applications. [ABSTRACT FROM AUTHOR]

Iris localization is the crucial link of iris recognition and automatic eye tracking. Based on the traditional Hough transform, this paper proposes an accurate pupil detection method combined with ellipse fitting and circular data compensation. We used the minimum gray mean method to approximately determine the inner edge. According to the results, the inner edge image is extracted and finely located by the center compensation method. When locating the outer boundary, a coarse localization is performed based on approximate radius compensation. The fine localization of the outer edge is performed based on approximate circle center compensation. The experimental results show the proposed algorithm improves the accuracy and real‐time performance of the localization compared with the traditional method. It retains the original advantages of Hough transform while reduces the amount of computation and useless information. [ABSTRACT FROM AUTHOR]

Aim: Precipitation manipulation experiments have shown diverse terrestrial carbon (C) cycling responses when the ecosystem is subjected to different magnitudes of altered precipitation, various experimental durations or heterogeneity in local climate. However, how these factors combine to affect C cycle responses to changes in precipitation remains unclear. Location: Global. Time period: 1990–2019. Major taxa studied: Terrestrial ecosystems. Methods: Using observations from 230 published studies in which precipitation was manipulated and terrestrial C cycling variables were measured, we conducted a global meta‐analysis to investigate responses of diverse C cycle processes to altered precipitation, including gross ecosystem productivity, ecosystem respiration, net ecosystem productivity, ecosystem carbon use efficiency, net primary productivity (NPP), aboveground and belowground NPP, aboveground and belowground biomass, shoot‐to‐root ratio, soil respiration and soil microbial biomass C. Results: We found that C cycling responses were correlated linearly and positively with the magnitude of precipitation treatments. We also detected that the responses of NPP and its aboveground component (ANPP) to altered precipitation weakened with experimental duration. Furthermore, gross ecosystem productivity, ecosystem respiration and net ecosystem productivity showed larger responses to precipitation treatments of greater magnitude over shorter time periods. The response of soil respiration, a key component of the C budget in most terrestrial ecosystems, depended in particular on the local climate. Local temperature and precipitation not only influenced the magnitude of the response of soil respiration to altered precipitation but also affected its sensitivity to the magnitude of the precipitation treatments, with higher sensitivities in the response of soil respiration to treatment magnitude at drier and colder sites. Main conclusions: Our findings highlight the importance of the interactions between the magnitude of precipitation treatments, their duration and the local climate in the response of ecosystem C cycling to altered precipitation, which is crucial to a better understanding of ecosystem C processes and functioning and projecting them under changing precipitation regimes. [ABSTRACT FROM AUTHOR]

Objectives: Salivary gland regeneration is closely related to the parasympathetic nerve; however, the mechanism behind this relationship is still unclear. The aim of this study was to evaluate the relationship between the parasympathetic nerve and morphological differences during salivary gland regeneration. Materials and Methods: We used a duct ligation/deligation‐induced submandibular gland regeneration model of Sprague‐Dawley (SD) rats. The regenerated submandibular gland with or without chorda lingual (CL) innervation was detected by haematoxylin–eosin staining, real‐time PCR (RT‐PCR), immunohistochemistry and Western blotting. We counted the number of Ki67‐positive cells to reveal the proliferation process that occurs during gland regeneration. Finally, we examined the expression of the following markers: aquaporin 5, cytokeratin 7, neural cell adhesion molecule (NCAM) and polysialyltransferases. Results: Intact parasympathetic innervation promoted submandibular gland regeneration. The process of gland regeneration was significantly repressed by cutting off the CL nerve. During gland regeneration, Ki67‐positive cells were mainly found in the ductal structures. Moreover, the expression of NCAM and polysialyltransferases‐1 (PST) expression in the innervation group was significantly increased during early regeneration and decreased in the late stages. In the denervated submandibular glands, the expression of NCAM decreased during regeneration. Conclusions: Our findings revealed that the regeneration of submandibular glands with intact parasympathetic innervation was associated with duct cell proliferation and the increased expression of PST and NCAM. [ABSTRACT FROM AUTHOR]

Structural engineering and creating atomic disorder in electrodes are promising strategies for highly efficient and rapid charge storage in advanced batteries. Herein, a nanohybrid architecture is presented with amorphous vanadium oxide conformally coated on layered V2C MXene (a‐VOx/V2C) via tunable anodic oxidation, which exhibits a high reversible capacity of 307 mAh g–1 at 50 mA g–1, decent rate capability with capacity up to 96 mAh g–1 at 2000 mA g–1, and good cycling stability as a cathode for sodium‐ion batteries. The a‐VOx layer enables reversible and fast Na+ insertion/extraction by providing sufficient vacancies and open pathways in the amorphous framework, unlike the irreversible phase transition in its crystalline counterpart, while layered V2C MXene offers abundant electron/ion transfer channels, which are joined together to boost the electrochemical performance. Notably the improved reversibility and structural superiority of the a‐VOx/V2C nanohybrid are clearly revealed by in situ Raman, in situ transmission electron microscopy, in situ synchrotron X‐ray absorption spectroscopy, and density functional theory calculations, demonstrating a reversible V–O vibration and valence oscillation between V4+ and V5+ in the disordered framework, with robust structural stability and unobstructed Na+ diffusion. This work provides a meaningful reference for the elaborate design of MXene‐based nanostructured electrodes toward advanced rechargeable batteries. [ABSTRACT FROM AUTHOR]

Summary: Whether and how warming alters functional traits of absorptive plant roots remains to be answered across the globe. Tackling this question is crucial to better understanding terrestrial responses to climate change as fine‐root traits drive many ecosystem processes.We carried out a detailed synthesis of fine‐root trait responses to experimental warming by performing a meta‐analysis of 964 paired observations from 177 publications.Warming increased fine‐root biomass, production, respiration and nitrogen concentration as well as decreased root carbon : nitrogen ratio and nonstructural carbohydrates. Warming effects on fine‐root biomass decreased with greater warming magnitude, especially in short‐term experiments. Furthermore, the positive effect of warming on fine‐root biomass was strongest in deeper soil horizons and in colder and drier regions. Total fine‐root length, morphology, mortality, life span and turnover were unresponsive to warming.Our results highlight the significant changes in fine‐root traits in response to warming as well as the importance of warming magnitude and duration in understanding fine‐root responses. These changes have strong implications for global soil carbon stocks in a warmer world associated with increased root‐derived carbon inputs into deeper soil horizons and increases in fine‐root respiration. [ABSTRACT FROM AUTHOR]

Nitrogen immobilization usually leads to nitrogen retention in soil and, thus, influences soil nitrogen supply for plant growth. Understanding soil nitrogen immobilization is important for predicting soil nitrogen cycling under anthropogenic activities and climate changes. However, the global patterns and drivers of soil nitrogen immobilization remain unclear. We synthesized 1350 observations of gross soil nitrogen immobilization rate (NIR) from 97 articles to identify patterns and drivers of NIR. The global mean NIR was 8.77 ± 1.01 mg N kg−1 soil day−1. It was 5.55 ± 0.41 mg N kg−1 soil day−1 in croplands, 15.74 ± 3.02 mg N kg−1 soil day−1 in wetlands, and 15.26 ± 2.98 mg N kg−1 soil day−1 in forests. The NIR increased with mean annual temperature, precipitation, soil moisture, soil organic carbon, total nitrogen, dissolved organic nitrogen, ammonium, nitrate, phosphorus, and microbial biomass carbon. But it decreased with soil pH. The results of structural equation models showed that soil microbial biomass carbon was a pivotal driver of NIR, because temperature, total soil nitrogen, and soil pH mostly indirectly influenced NIR via changing soil microbial biomass. Moreover, microbial biomass carbon accounted for most of the variations in NIR among all direct relationships. Furthermore, the efficiency of transforming the immobilized nitrogen to microbial biomass nitrogen was lower in croplands than in natural ecosystems (i.e., forests, grasslands, and wetlands). These findings suggested that soil nitrogen retention may decrease under the land use change from forests or wetlands to croplands, but NIR was expected to increase due to increased microbial biomass under global warming. The identified patterns and drivers of soil nitrogen immobilization in this study are crucial to project the changes in soil nitrogen retention. [ABSTRACT FROM AUTHOR]

Exploiting highly effective and low‐cost electrocatalysts for the hydrogen evolution reaction (HER) is a pressing challenge for the development of sustainable hydrogen energy. In this work, a facile and industrially compatible one‐pot corrosion strategy for the rapid synthesis of amorphous RuO2‐decorated FeOOH nanosheets on iron foam (FFNaRu) within 1 h is reported. Corrosion is a common and inevitable phenomenon that occurs on metal surfaces without electricity input, high temperature, and tedious synthetic procedures. The FFNaRu electrode is superhydrophilic and aerophobic, which guarantees intimate contact with the electrolyte and accelerates the instantaneous escape of produced gas bubbles during the electrocatalytic process. Moreover, the strong electronic interactions between RuO2 and FeOOH promote the electrocatalytic process via dramatically improving the electrochemical interfacial properties. Thus, the FFNaRu electrocatalyst presents excellent catalytic activity towards the HER (30 mV at 10 mA cm–2) and overall water‐splitting (230 mV at 10 mA cm–2) in 1 M KOH. The overall water‐splitting could be simply powered by sustainable and intermittent sunlight, wind, and thermal energies motivated Stirling engine. Density functional theory calculations confirm that coupling effects between RuO2 and FeOOH are also responsible for promoting the electrocatalytic HER performance. [ABSTRACT FROM AUTHOR]

With the help of the high‐spatial‐resolution total electron content (TEC) data obtained by Mars Advanced Radar for Subsurface and Ionospheric Sounding on board the Mars Express (MEx) during June 2005 to September 2007, the detailed configurations of the Martian nightside ionosphere in crustal magnetic field cusp regions are researched in this paper. It is found that double‐peak structures of orbital observed TEC values frequently appeared when MEx was crossing through the strong crustal magnetic field cusp regions. This observational result implies that the Martian nightside TECs in the periphery of the cusp regions are generally higher than those in the central areas of the cusp regions, a phenomenon never reported before. By combining the TEC data with the in‐situ electron flux data obtained by the Analyzer of Space Plasma and Energetic Atoms‐3 (ASPERA‐3), it is found that the difference between the fluxes of the electrons precipitating in the central and peripheral areas of the cusp regions can be responsible for the observed TEC double‐peak structures. Plain Language Summary: Martian ionosphere on the nightside is an area far from well understood. According to previous researches, in areas with strong crustal magnetic fields, the Martian nightside ionosphere would be denser in cusp regions. However, in this research, we find that the Martian nightside total electron contents (TECs) in the center of the crustal magnetic cusp regions are generally lower than those in the periphery of the cusp regions. As far as we know, this phenomenon was never found before. By combining the TEC data with the observations on the precipitating electrons, we further find that the difference between the flux of the electrons precipitating in the center and periphery of the cusp regions can be responsible for this phenomenon. Our study shows a more detailed TEC structure in the cusp regions and suggests that the effects of the Martian crustal magnetic fields on the nightside ionosphere and plasma transfer are very complicated and need more researches. Key Points: Patterns of total electron content (TEC) near strong crustal magnetic fields in the Martian nightside ionosphere are investigatedDouble‐peaked TEC structures are observed ∼50% of the time in the open magnetic field regionsThe TEC double‐peak structures are associated with inhomogeneous patterns of precipitating electrons in these regions [ABSTRACT FROM AUTHOR]