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The ever-growing sizes and frequent updating of mobile applications cause high network and storage cost for updating. Hence, emerging mobile systems often employ incremental update algorithms, typically HDiffPatch, to upgrade mobile applications. However, we find that existing incremental update algorithms not only generate a significant amount of redundant data accesses, but also lacks of consistency guarantees for the whole package of application. In this paper, we present a novel Consistent and Efficient Incremental Update (CEIU) mechanism for upgrading mobile applications. Firstly, CEIU reduces the memory consumption and file access of incremental updates by reusing the indexes of blocks in the old image rather than copying the blocks. Secondly, CEIU employs a two-level journaling mechanism to ensure the consistency of the whole package and subfiles of the new image. We implement the proposed mechanism in Linux kernel based on TI-LFAT file system and evaluate it with real-world applications. The experimental results show that the proposed mechanism can reduce 30%–80% memory footprints in comparison with HDiffPatch, the state-of-the-art incremental update algorithm. It also significantly reduces the recovery time when power failure or system crash occurs. [ABSTRACT FROM AUTHOR]

Lead-free bismuth sodium titanate-strontium titanate (NBT-ST) dielectric ceramic materials have been extensively investigated energy storage materials because of their relaxor characteristics. In this study, four different lanthanide elements were introduced into the ferroelectric NBT-ST ceramic to improve their relaxor properties. The introduction of the lanthanide resulted in an increase in disorder at location A within the perovskite lattice and improved relaxor characteristics, leading to a stored energy density of more than 3.5 J/cm3. In particular, an ultrahigh recoverable stored energy density of 4.94 J/cm3 and efficiency of 88.45% were achieved at 440 kV/cm when the NBT-ST ceramic was modified with neodymium. The modified ceramic also exhibited good thermal stability in the range of 30–120 °C, as well as a fast discharge time of ∼153 ns, indicating that Nd-incorporated NBT-ST is a promising candidate for electrical energy storage ceramic. [ABSTRACT FROM AUTHOR]

Na 0.5 Bi 0.5 TiO 3 (NBT)-based ceramics exhibit significant potential as energy storage dielectric materials due to their high maximum polarization (P max). However, their limited energy storage density significantly restricts their practical applications. To address this, this study optimizes the dielectric energy storage characteristics of lead-free relaxor ferroelectric ceramics based on 0.91Na 0.5 Bi 0.5 TiO 3 -0.09 K 0.7 La 0.1 NbO 3 (NBT-KLN) by incorporating Sr 0.7 Bi 0.2 TiO 3 (SBT) relaxor additives. The introduction of SBT helps maintain large polarization and induces local disorderly fields, promoting the formation of polar nanoregions. Subsequently, a viscous polymer processing (VPP) technique was employed to reduce defects and enhance density, markedly improving the breakdown strength (BDS). The findings indicate that the BDS of the optimized 0.30SBT (VPP) ceramics increased to 440 kV/cm, while achieving a high energy storage efficiency (η) of 78 % and an elevated energy storage density (W rec) of 6.29 J/cm3. Additionally, the 0.30SBT (VPP) ceramics demonstrate excellent temperature stability across a broad temperature range from 30 to 120 °C, making them ideal for long-term operation in variable environments. This study demonstrates superior results compared to previous research, thereby opening up new avenues for developing novel lead-free relaxor ferroelectric ceramics with superior energy storage characteristics. • A synergistic strategy enhances dielectric ceramics' energy storage by optimizing composition and process. • TEM analysis has clarified the enhancement mechanism of energy storage in 0.30SBT ceramics has been elucidated. • Under a 440 kV/cm field, 0.30SBT(VPP) ceramic achieves 6.29 J/cm3 W rec , 78% η , excellent stability (30–120℃, 1–120 Hz), and a 137 ns discharge time. [ABSTRACT FROM AUTHOR]

Ceramic materials with relaxor dielectric properties, expressed as (1- x)(0.94Na 0.5 Bi 0.5 TiO 3 -0.06LiTaO 3)- x CaTiO 3 [(1- x)(NBT-LT)- x CT] with x values of 0.12, 0.15, 0.18, and 0.21, were synthesized through an A-site doping method to enhance energy storage capabilities. The linear dielectric CaTiO 3 was chosen as the acceptor additive, and ceramic samples were prepared using conventional solid-phase and molding techniques. A comprehensive investigation evaluated the influence of different CT concentrations on the phase and energy storage/release characteristics of NBT-LT. Optimal performance was notably achieved with a 15% CT doping concentration, resulting in W rec and η values of 2.16 J/cm³ and 70%, respectively, for a 100 μm thick sample under a 210 kV/cm voltage. When the film was rolled to a 60 μm thickness, the voltage strength increased to 330 kV/cm, leading to enhanced W rec (5.33 J/cm³) and η (80%). Within the temperature range of 30 °C to 150 °C, only a marginal change in W rec (less than 10%) was observed. Frequency conversion tests across the 1 Hz to 100 Hz range demonstrated the material's relative stability, with W rec exhibiting minimal fluctuations. These findings emphasize the outstanding temperature and frequency stability of the material. During discharge, the material displayed a power density of up to 152 MW/cm³, coupled with a discharge time of 0.3 μs, showcasing remarkable pulse discharge capabilities. The experimental results affirm the promising potential of (NBT-LT)-0.15CT lead-free relaxor ferroelectric ceramics for application in commercial capacitors. • A strategy of composition modification and processing improvement to enhance dielectric energy storage performance has been raised. • Achieve an ultrahigh W rec of 5.33 J/cm3 and high η of 80% in NBT-LT-0.15CT VPP ceramic under an electric field of 330 kV/cm. • Possess high power density of ∼ 152 MW/cm3 and fast discharge time of ∼ 0.22 μs. [ABSTRACT FROM AUTHOR]

The alpine meadow located in permafrost is crucial for ecosystem services of the Qinghai-Tibet Plateau (QTP), which is experiencing precipitation changes in most areas. Water use efficiency (WUE) can quantify the inextricable link between carbon assimilation and water loss in terrestrial ecosystems. However, the temporal variations in WUE and its driving factors across different precipitation years still need to be clarified in alpine meadows on the QTP. Therefore, 4-year carbon and water flux data were used to elucidate the mechanisms behind seasonal and interannual variations in WUE of an alpine meadow in the hinterland of the QTP. Noticeable seasonal variations in WUE were observed during the studied period, with the highest value (1.38±0.38 g C kg−1 H 2 O) occurring during the mid-growing season (MG, starting around 166 DOY), approximately 2 and 3 times those during the late-growing season (LG, starting around 256 DOY and ending around 282 DOY) and early-growing season (EG, starting around 140 DOY), respectively. Standardized total effects in the structural equation models from NDVI to WUE were highest in all seasons, indicating that NDVI was the primary controlling factor for daily WUE variations. Additionally, energy factors (temperature and solar radiation) also significantly influenced daily WUE variations. The highest mean daily WUE (1.23±0.65 g C kg−1 H 2 O) was in the mild dry year (2016). However, no significant differences were noted in mean daily WUE in severe dry (2015) and wet (2019) years compared to the normal year (2020) during GS. This can be attributed to the varying sensitivity of carbon assimilation and water loss to biotic and abiotic changes across divergent precipitation years, with WUE exhibiting a greater sensitive to gross primary productivity than to evapotranspiration. These findings suggest that alpine meadows have endured in its harsh environment and have adapted to climatic fluctuations through long-term evolution. • No significant changes in evapotranspiration across different years in the alpine meadow. • Plant growth status determined the changes in gross primary productivity. • Water use efficiency (WUE) were more sensitive to changes in carbon assimilation than to water loss. • NDVI was the primary driver for variations in daily WUE in the alpine meadow. • No significant difference in WUE between the severe dry and wet years in the alpine meadow. [ABSTRACT FROM AUTHOR]

A novel strategy of enhancing the dielectric and energy storage properties of Na 0.5 Bi 0.5 TiO 3 –BaTiO 3 (NBT–BT) ceramics by introducing a K 0.5 Na 0.5 NbO 3 (KNN) ferroelectric phase is proposed herein, and its underlying mechanism is elucidated. The lead-free KNN ceramic decreases the residual polarisation and increases the electric breakdown strength of the NBT–BT matrix through the simultaneous modification of its A-sites and B-sites. The obtained NBT−BT− x −KNN ceramics have a perovskite structure with unifying grains. A bulk 0.9NBT–BT–0.1KNN ceramic sample with a thickness of 0.2 mm possesses a high energy storage density of 2.81 J/cm3 at an applied electric field of 180 kV/cm. Moreover, it exhibits good insulation properties and undergoes rapid charge and discharge processes. Therefore, the obtained 0.9NBT–BT–0.1KNN ceramic can be potentially used in high-power applications because of its high energy density, good insulation properties, and large discharge rate. [ABSTRACT FROM AUTHOR]

Na 0.5 Bi 0.5 TiO 3 -based ceramic specimens have been extensively investigated as ferroelectric materials. After being doped with CaTiO 3 , the resulting Na 0.5 Bi 0.5 TiO 3 -based ceramics exhibit relaxor characteristics, and improved energy storage density and efficiency. Based on these above results, CeO 2 was further employed to modify the polarization of the 0.85Na 0.5 Bi 0.5 TiO 3 -0.15CaTiO 3 matrix ceramic to achieve better energy storage performance. The effective energy storage density was enhanced from 1.93 to 2.53 J/cm3 by using the appropriate doping concentration of CeO 2. Grain refinement effect can effectively enhance the electric-field strength from approximately 190 to 230 kV/cm. In particular, when doped with 2% CeO 2 , the energy storage efficiency of the sample was maintained at approximately 90% at 30 °C-150 °C and at approximately 80% in the frequency range of 0.2–200 Hz. This combination has very excellent temperature stability and frequency stability, making it a promising candidate for energy storage applications. [ABSTRACT FROM AUTHOR]

In the current study, a series of CeO 2 -doped (x = 0.01, 0.015, 0.02, 0.025 mol) ceramic samples were prepared, and the valence of Ce in the perovskite was analyzed in detail, revealing the polarization contribution and effect mechanism of the doped Ce element in the 0.65BaTiO 3 –0.35Sr 0.7 Bi 0.2 TiO 3 ceramic. The phase structure and electrical stored energy performance of the resulting ceramics were also characterized. It was found that adding an appropriate amount of CeO 2 to BaTiO 3 was helpful for improving the relaxor behavior, promoting electric storage, and releasing ceramic materials. Particularly, the electric breakdown strength of the 0.02Ce-doped specimen reached 330 kV/cm, and the corresponding density and efficiency were 2.57 J/cm3 and 81.30%, respectively. In addition, doping with Ce caused the ceramics to exhibit good stability at frequencies of 1–300 Hz and over a temperature range of 30–150 °C. A high current density (C D) and power density (P D) were obtained in charge–discharge tests. [ABSTRACT FROM AUTHOR]

• A single atomic Ag- g -C 3 N 4 (SAACN) with 10 wt% loading of Ag catalyst is designed. • When using SAACN, 17.24% of dissolved O 2 is converted to reactive oxygen species. • The rate constants (k) for degrading the tetracycline are 0.0409 min-1 over SAACN. • Abundant ROS generate over SAACN due to O 2 adsorption and electron transfer. • A potential method for converting O 2 into ROS and degraded pollutants is provided. Photocatalytic activation of molecular oxygen (O 2) is a promising way in oxidative degradation of organic pollutants. However, it suffers from low efficiency mainly due to the limited active sites for O 2 activation over traditional photocatalysts. Therefore, we established a single atomic Ag- g -C 3 N 4 (SAACN) catalyst with 10 wt% loading of Ag single sites for boosting the O 2 activation during the degradation of tetracycline (TC), and 10 wt% loading of nanoparticle Ag- g -C 3 N 4 (NPACN) was studied as a comparison. When using SAACN, the accumulative concentration of superoxide (•O 2 −), hydroxyl radical (•OH), singlet oxygen (1O 2) reached up to 0.66, 0.19, 0.33 mmol L−1h−1, respectively, within 120 min, 11.7, 5.7 and 4.9 times compared with those using NPACN, representing 17.24% of dissolved O 2 was converted to reactive oxygen species (ROS). When additionally feeding air or O 2, the accumulative concentrations of •O 2 −, •OH, 1O 2 were even higher (air: 4.21, 0.97, 2.02 mmol L−1 h−1; O 2 : 17.13, 1.32, 9.00 mmol L−1 h−1). The rate constants (k) for degrading the TC were 0.0409 min−1 over SAACN and 0.00880 min−1 over NPACN, respectively (mineralization rate: 95.7% vs. 59.9% after 3 h of degradation). Moreover, the degradation ability of SAACN did not decrease in a wide range of pH value (4–10) or under low temperature (10 °C). Besides the high exposure of Ag single sites, other advances of SAACN were: 1(O 2 was more energetic favorable to adsorb on single atomic Ag sites; 2) Positive Ag single sites were easier to obtain the electrons from the surrounding N atoms, and facilitated electron transfer towards adsorbed O 2. [Display omitted] [ABSTRACT FROM AUTHOR]

• Coexisting species exhibited large overlaps of water sources. • Plants shifted their water uptake to deeper soil as soil moisture increased. • Proportions of plant-available water and gravity water adjusted plant water uptake. • Plants at the lowest altitude obtained more shallow soil water. Soil water is crucial for maintaining forest health by providing plants with a dependable water source. However, the understanding of the impact of soil moisture on plant water uptake, particularly in conditions of excess soil water, is limited. In this study, we investigated root water uptake strategies of dominant species along an elevational gradient in the subalpine region of the eastern Qinghai–Tibet Plateau. Our results demonstrated divergent relationships between soil moisture and water uptake fractions in the shallow soil layer, where moisture generally exceeds field capacity (θ f c) during the growing season, and in the deep soil layer, showing negative and positive associations, respectively. This disparity is linked to soil water components: when plants mainly used shallow soil water, the relative proportion of plant–available water (the part of water between wilting coefficient and θ f c) in the shallow soil was smaller compared to instances where plants mainly used deep soil water. Conversely, the pattern for gravity water was the opposite. This phenomenon is attributed to precipitation replenishing shallow soil with gravity water and deep soil with plant–available water, leading to poor aeration in the shallow soil and an abundance of plant–available water in the deep soil, and plants tended to shift to deep soil water as a result. Furthermore, the decrease in the relative proportion of plant–available water in the shallow soil along the elevational gradient results in plants in the lowest-altitude broadleaf forest obtaining more shallow soil water and less deep soil water, which can also enhance our understanding of how soil moisture components influence plant water–use strategies. Additionally, no hydrological niche segregation was observed among species in this humid environment. These results can improve our comprehension of soil–plant interactions in subalpine areas. [ABSTRACT FROM AUTHOR]

A conventional preparation method of electroceramics was used to synthesise Pb-free 0.85Na 0.5 Bi 0.5 TiO 3 -0.15CaTiO 3 - x La (NBT-CT- x La) ceramics. La3+ doping effectively refined the grains and enhanced the dielectric breakdown strength (BDS) of the ceramics; this result was confirmed by numerical simulations, which revealed that grain refinement significantly contributed to the enhancement of the BDS. The energy storage density consequently improved when an appropriate amount of La3+ was added to the NBT-CT ceramics. In particular, the NBT-CT-0.75La ceramic displayed a maximum energy storage density of 2.15 J/cm3 and a high BDS of 210 kV/cm. This ceramic also possessed relatively excellent temperature and frequency stabilities (30–150 °C, 0.2–200 Hz). Moreover, the ceramics exhibited exceptional charge–discharge performances, with an outstanding power density of 43.87 MW/cm3, which is nearly twice of that of other NBT-based ceramics. On the basis of the findings, the NBT-CT-0.75La ceramic can be considered to be a promising candidate material for the pulsed power application. [ABSTRACT FROM AUTHOR]

Alpine grasslands are the dominant vegetation of the Tibetan Plateau (TP) and are essential to understanding the mechanism of change in water use efficiency (WUE) in high-cold ecosystems in a changing environment. However, it is still unclear how the WUE of different alpine grasslands respond to changes in precipitation. Therefore, we investigated the variations in growing season WUE and its drivers among different grassland types, including alpine meadow of permafrost (PAM), alpine meadow of seasonal frost (SAM), alpine steppe of permafrost (PAS), and alpine steppe of seasonal frost (SAS), in different precipitation years. The mean growing season WUE was significantly higher for alpine meadow and seasonal frost regions and lower for alpine steppe and permafrost regions. WUE increased significantly in the alpine meadow (PAM and SAM) but decreased (PAS) or varied little (SAS) in the alpine steppe during the period of 1982–2014. Compared to normal years, WUE in the PAS region increased by 22% and 10% in severe and mild dry years, respectively, and decreased by approximately 10% in wet years. For the alpine meadow, WUE decreased more in severe dry years than in mild dry years and increased slightly in wet years. In different precipitation years, WUE for all grassland types was mainly controlled by the vegetation factor. Results suggest that the WUE in alpine grasslands, especially in the PAS region, may decline if the "dry gets wet, wet gets dry" happen over the TP in the future. • Increasing soil moisture dominated the increasing water use efficiency (WUE) in the alpine meadow ecosystems. • Decreasing WUE in the alpine steppe of permafrost was due to the negative effect of precipitation and soil moisture on WUE. • Contrasting responses of WUE to precipitation changes were observed in the alpine steppe and alpine meadow ecosystems. [ABSTRACT FROM AUTHOR]

• Climate change fueled substantial increases in water and sediment fluxes. • The seasonal freeze-thaw cycles changed the soil erosion patterns. • Higher-frequency rainstorm events exacerbated freeze-thaw erosion. • In the initial thaw and freezing periods, sediment fluxes substantially increased. • The extension of the thawing duration increased the sediment supply. Variations in the suspended sediment on the Qinghai–Tibet Plateau have important implications for aquatic ecosystems. Although changes in the cryosphere induced by climate change have been shown to increase sediment yields, their impacts on water and sediment dynamics in headwater regions remain poorly investigated. Here, we examined the responses of runoff and suspended sediment dynamics to changes in the climate and ground freeze–thaw cycle in the source region of the Yangtze River (SRYR) from 1964 to 2019. Long–term daily in situ water and sediment observations provided evidence that climate change controlled change in seasonal and annual water–sediment dynamics by regulating air temperature and precipitation. Attribution analysis showed that precipitation (∼41.93 %, through driving rainfall splash, overland flow erosion, and mass wasting) and land surface temperature (∼30.66 %, through driving freeze–thaw erosion) were the major factors contributing to increasing fluvial sediment fluxes over the past 30 years. We found that freeze–thaw cycles changed the soil erosion patterns by governing the thermal state of the near–surface active layer and driving associated thermal processes. Furthermore, the extension of the thawing duration and the advance of the thawing starting date (at an average rate of 13.5 days/10 yr) exacerbated freeze–thaw erosion, leading to elevated sediment fluxes in the initial thaw and initial freezing periods. This study highlights the need to focus on cryosphere–hydrology observations in terms of sediment dynamics; these findings are critical for soil and ecological protection in alpine headwater regions. [ABSTRACT FROM AUTHOR]

Regional quantification of soil CO 2 and CH 4 fluxes in boreal forests remains difficult because of high landscape heterogeneity and fire disturbance coupled with a sparse measurements network. Most of the work focuses on the separate effects of fire or topography, and as a result, the spatial variability in the response of soil carbon flux to fire remains unclear. A two-year field experiment was conducted in the boreal forest of the DaXing’anling Mountains to investigate the effects of topography (ridge and depression) and fire on soil CO 2 and CH 4 fluxes and to determine how the effects of fire vary with topography. The results showed that soil carbon flux to the atmosphere in this region was dominated by soil CO 2 flux. Topography had significant effect on soil carbon fluxes, with higher soil CO 2 emissions and CH 4 uptakes on the ridge than in the depression, whether burned or not, and these topographical differences were amplified by fire. Fire significantly increased soil CO 2 emissions and CH 4 uptakes both in the depression and on the ridge. However, the factors that determined soil CO 2 and CH 4 fluxes and the extent of the response to fire varied with topography. Although the depression released less soil carbon to the atmosphere, the increase in Q 10 of soil CO 2 flux and the permafrost degradation following fire in the depression indicated stronger positive feedbacks to climate warming. To concluded, topography regulated the effects of fire on soil carbon fluxes and might control the post-fire soil carbon flux feedbacks to climate warming. Therefore, large-scale predictions of soil carbon fluxes in response to fire in the boreal region must explicitly incorporate topographic features. [ABSTRACT FROM AUTHOR]

The limited number of in situ measurements of greenhouse gas (GHG) flux during soil freeze-thaw cycles in permafrost regions limits our ability to accurately predict how the alpine ecosystem carbon sink or source function will vary under future warming and increased nitrogen (N) deposition. An alpine meadow in the permafrost region of the Qinghai-Tibet Plateau was selected, and a simulated warming with N fertilization experiment was carried out to investigate the key GHG fluxes (ecosystem respiration [Re], CH 4 and N 2 O) in the early (EG), mid (MG) and late (LG) growing seasons. The results showed that: (i) warming (4.5 °C) increased the average seasonal Re, CH 4 uptake and N 2 O emission by 73.5%, 65.9% and 431.6%, respectively. N fertilization (4 g N m −2 ) alone had no significant effect on GHG flux; the interaction of warming and N fertilization enhanced CH 4 uptake by 10.3% and N 2 O emissions by 27.2% than warming, while there was no significant effect on the Re; (ii) the average seasonal fluxes of Re, CH 4 and N 2 O were MG > LG > EG, and Re and CH 4 uptake were most sensitive to the soil freezing process instead of soil thawing process; (iii) surface soil temperature was the main driving factor of the Re and CH 4 fluxes, and the N 2 O flux was mainly affected by daily rainfall; (iv) in the growing season, warming increased greenhouse warming potential (GWP) of the alpine meadow by 74.5%, the N fertilization decreased GWP of the warming plots by 13.9% but it was not statistically significant. These results indicate that (i) relative to future climate warming (or permafrost thawing), there could be a hysteresis of GHG flux in the alpine meadow of permafrost region; (ii) under the scenario of climate warming, increasing N deposition has limited impacts on the feedback of GHG flux of the alpine meadow. [ABSTRACT FROM AUTHOR]

[Display omitted] • Low-flow components can be determined through FDC, baseflow, and recession processes. • Sub-permafrost groundwater is the main component of baseflow in permafrost regions. • Q94 can be used to fully represent sub-permafrost groundwater. Baseflow is an important component of streamflow in alpine permafrost basins and plays a significant role in maintaining ecosystem security and rational planning of water resources. Meanwhile, a holistic analysis of the runoff process and determination of low-flow components helps to better understand hydrological processes in permafrost regions. In this context, an approach for determining low-flow components is presented. As a support, daily flow data regarding the source regions of the Yangtze River (YARSR) and Yellow River (YERSR) from 1965 to 2014 were divided into three groups (wet, normal, and dry years) to analyze baseflow, recession curves, and flow duration curves (FDC). The results showed that low-flow components can be determined from the corresponding relationship between percentile flow (Q pi) in FDC, baseflow, and recession processes. Sub-permafrost groundwater is the main component of baseflow in the permafrost regions of the Qinghai-Tibet Plateau. The multi-year average proportion of sub-permafrost groundwater in YARSR and YERSR at Q75, Q85, and Q94 ranged from 75.5% to 100%, suggesting the dominance of sub-permafrost groundwater in sustaining low-flows. In addition, river discharge in dry years was more dependent on deep groundwater. The sub-permafrost groundwater proportion in low-flows in dry years (76%–95%) was greater than that of wet years (64%–86%). We also found that sub-permafrost groundwater flows increased significantly with permafrost degradation. Sub-permafrost groundwater flows increased more rapidly than that of supra-permafrost groundwater flows over the past decades. Future climate change may further affect runoff composition in permafrost rivers; and our method has great potential to characterize it. [ABSTRACT FROM AUTHOR]

Write amplification inside the flash memory device is a severe problem, which shortens the flash's lifespan and degrades its performance. The TRIM command is proposed to reduce write amplification by avoiding unnecessary relocation in flash memory devices. However, the significant overhead causes the TRIM command to be completely prohibited by common file systems when I/O is busy. This completely prohibited TRIM strategy not only affects the lifespan of the flash memory device but also degrades the performance due to the huge write amplification. In this paper, we propose CoDiscard, a revenue model based cross-layer cooperative discarding mechanism, to optimize the I/O performance and reduce write amplification under intensive workloads. The core idea of CoDiscard is to sieve the high performance–price-ratio TRIM commands to the flash memory device because they can reduce write amplification significantly, thus improving performance. To identify such TRIM commands, we propose a revenue model to predict the write amplification reduction and the corresponding overhead. Based on the revenue model, CoDiscard employs a cross-layer cooperative scheme to schedule the TRIM command. The CoDiscard scheduler in the file system is responsible for making decisions. The CoDiscard monitor in the flash memory device is used to monitor the changing of revenue model related information. We conduct the experiment under real workloads. The results show that the performance improves for 113% and 118.4%, and the write amplification reduces up to 12.12 × and 8.18 ×. [ABSTRACT FROM AUTHOR]

• Ecosystem respiration (Re) and methane fluxes were measured in a Tibetan grassland. • The microbial factor directly affects Re in an alpine grassland within watersheds. • Greater soil moisture caused a weak methane sink at the lower slope positions. Ecosystem respiration (Re) and methane (CH 4) fluxes are two important soil-atmosphere carbon exchange processes that have been well documented at the local scale. However, the spatial patterns and controlling factors of these processes remain unclear in the Tibetan alpine permafrost region at the watershed scale. We conducted a two-year field monitoring study of Re and CH 4 fluxes at three altitudinal positions on shady and sunny slopes in a Tibetan alpine grassland to determine the spatial variability in the two processes and to identify their underlying mechanisms. The microbial factor had a controlling effect on Re spatial variability in alpine grassland watersheds. The lower soil temperature and soil organic matter content at the upper slope positions on the shady slopes inhibited Re because they reduced the soil microbial activity. We found that the alpine grassland to be a net sink of atmospheric CH 4 , and the average CH 4 flux rates exhibited large spatial variance ranging from −1.60 to −10.48 µg CH 4 m−2 h−1 within the watersheds. The spatial variability in soil volumetric water content explained 76% of the variation in CH 4 fluxes within the watersheds. We suggest that the influence of permafrost on hydrologic conditions may increase the spatial variability of soil moisture (measured as soil volumetric water content and water-filled pore space) in alpine grassland watersheds, and generally form poorly drained landscape at the lower slope position where Re and CH 4 uptake are inhibited. Our results highlight the indirect effects of terrain and permafrost on Re and CH 4 fluxes through their effects on biophysiochemical factors. We recommend that the spatial variability in Re and CH 4 fluxes at the watershed scale of Tibetan alpine grassland should be given more attention in earth system models, especially the variability of CH 4 fluxes with altitudinal position. [ABSTRACT FROM AUTHOR]

Due to the merits of high safety and easy preparation, dielectric ceramics have become key engineering materials for capacitors. Within this article, different contents of Na 0.5 Bi 0.5 TiO 3 were introduced into Ba 0.65 Sr 0.245 Bi 0.07 TiO 3 relaxor ferroelectric ceramics in order to increase the disorder degree of A-site ions in perovskite structure and modify the relaxation, which could generate liquid sintering promoting densification, then finally enhancing the dielectric energy store performance of ceramics. The research results show that all the bulk samples prepared through traditional processing route are exhibiting pseudocubic perovskite structure, and their surfaces are with Na 0.5 Bi 0.5 TiO 3 (NBT)-rich phase formed during densification due to a relatively low sintering temperature of NBT. The relaxation coefficient of BT-SBT-0.01NBT ceramic is 1.8. Because of the existence of liquid phase formation during sintering, the dielectric breakdown strength (BDS) of BT-SBT-0.01NBT ceramic is increased to 230 kV/cm, and the recoverable energy density (W rec) reached 2.22 J/cm3. The introduction of NBT can hence enhance the relaxation and BDS, finally elevate the energy storage performances. • The energy storage performance can be effectively improved by increasing the disorder degree of the A-site ions. • NBT could generate liquid sintering promoting densification and enhancing the BDS from 120 to 230 kV/cm. • The W rec of BT-SBT-0.01NBT is increased to 2.22 J/cm3, which is nearly three times higher than that of BT-SBT. [ABSTRACT FROM AUTHOR]

Photocatalysts of one-dimensional (1D) Mn x Cd 1-x S nanorods (NRs) were synthesized by decomposing complex precursors. The photocatalytic experiments confirmed that Mn x Cd 1-x S samples presented an enhanced photocatalytic property due to Mn2+ doping. The optimal Mn2+ concentration of x = 0.02 showed the highest photocatalytic performance. Moreover, the Mn 0.02 Cd 0.98 S sample had a universal and stable photocatalytic property in the visible light range. We attributed the enhanced photocatalytic activity to the shallow trapping sites and the narrow energy band gap derived from the appropriate Mn2+ doping, which promote efficient charge separation. • Mn x Cd 1-x S NRs were fabricated by one-pot solvothermal route. • Mn 0.02 Cd 0.98 S NRs exhibited excellent photocatalytic activity and durability. • O 2. • − was the dominant reactive species for the degradation of RhB dye. • The enhanced activity is due to shallow trapping sites and bandgap narrowing. [ABSTRACT FROM AUTHOR]

The feedback between the atmosphere and permafrost soils containing large carbon stocks is currently considered the most important carbon-cycle feedback, but it is missing from climate models due to many uncertainties. Knowledge of how differences in post-thaw hydrological conditions affect carbon (C) release is critical for predicting permafrost feedback, but this knowledge remains limited. In this study, permafrost and active layer soils from the southern margin of the Eurasian boreal permafrost region in Northeast China were collected and incubated under experimentally modified moisture to monitor their CO 2 and CH 4 productions under simulated natural, drier and flooded conditions. We also characterized soil properties related to soil organic carbon (SOC) quality and microbial activities to determine their relations with measured C productions. We found that permafrost had higher C release per gram of SOC basis (C vulnerability) than the active layer, which suggested that there would be a high risk for C emissions in the permafrost region when permafrost thaws in the warming future. However, hydrological conditions following the permafrost thaw control these emissions. Permafrost C decomposed in relatively aerobic upland systems had higher C emissions than that decomposed in anaerobic wetland environments. Our results suggest a greater climate forcing of C release in aerobic than anaerobic conditions, but there are some uncertainties resulting from the unknown long-term CH 4 production rates. Moreover, we found that the aerobic C production in permafrost after thawing could be constrained by water stress, suggesting that previous predictions based on soil incubations at natural soil moisture might overestimate the aerobic permafrost C release. • Permafrost has higher C vulnerability than active layer in boreal forest. • Permafrost C release would be limited by drier soil condition. • Climate forcing of C released in aerobic conditions was greater than in anaerobic conditions in the long run. • Soil moisture was the primary factor associated with aerobic C production. [ABSTRACT FROM AUTHOR]

Climate-sensitive northern cryosphere inland waters emit greenhouse gases (GHGs) into the atmosphere, yet their total emissions remain poorly constrained. We present a data-driven synthesis of GHG emissions from northern cryosphere inland waters considering water body types, cryosphere zones, and seasonality. We find that annual GHG emissions are dominated by carbon dioxide ([Formula: see text] teragrams of CO 2 ; [Formula: see text]) and methane ([Formula: see text] teragrams of CH 4 ), while the nitrous oxide emission ([Formula: see text] gigagrams of N 2 O) is minor. The annual CO 2 -equivalent (CO 2 e) GHG emissions from northern cryosphere inland waters total [Formula: see text] or [Formula: see text] petagrams of CO 2 e using the 100- or 20-year global warming potentials, respectively. Rivers emit 64% more CO 2 e GHGs than lakes, despite having only one-fifth of their surface area. The continuous permafrost zone contributed half of the inland water GHG emissions. Annual CO 2 e emissions from northern cryosphere inland waters exceed the region's terrestrial net ecosystem exchange, highlighting the important role of inland waters in the cryospheric land-aquatic continuum under a warming climate.

In the context of climate change, extreme precipitation events are continuously increasing and impact the water‑carbon coupling of ecosystems. The vertical vegetation zonation, as a characteristic of mountain ecosystems, reflects the differences in vegetation response to climate change at different elevations. In this study, we used the water use efficiency (WUE) as an indicator to evaluate the water‑carbon relationship. By using MODIS data, we analyzed the spatiotemporal patterns of gross primary productivity (GPP), evapotranspiration (ET), and WUE from 2001 to 2020, as well as the responses of WUE to extreme wetness factor Number of precipitation days (R0.1), extreme dryness factor Consecutive dry days (CDD), and meteorological factors under the vertical vegetation zonation. Our results showed that annual GPP and ET displayed a significant increasing trend between 2001 and 2020, whereas WUE showed a weak decreasing trend. Spatially, GPP and WUE decreased with increasing elevation. Analyzing the WUE of mountainous ecosystems as a unified whole may not precisely capture the reactions of vegetation to severe rainfall occurrences. In fact, across different vegetation belts in mountainous areas, there exists a negative correlation between WUE and R0.1, and a positive correlation with CDD. In terms of meteorological factors, the temporal variation of GPP was primarily associated with vapor pressure deficit (VPD) and temperature (Ta), while those of ET was mainly related to soil water content (SWC). WUE was affected by a combination of meteorological factors and had a certain degree of variation between different altitude intervals. These findings contribute to a better understanding and prediction of the relationship between extreme rainfall climate and water‑carbon coupling in mountainous areas., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Xiangyang Sun reports financial support was provided by National Natural Science Foundation of China. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Purpose: Histopathological growth patterns (HGPs) of colorectal liver metastases (CRLMs) have prognostic value. However, the differentiation of HGPs relies on postoperative pathology. This study aimed to develop a magnetic resonance imaging (MRI)-based radiomic model to predict HGP pre-operatively, following the latest guidelines., Methods: This retrospective study included 93 chemotherapy-naïve patients with CRLMs who underwent contrast-enhanced liver MRI and a partial hepatectomy between 2014 and 2022. Radiomic features were extracted from the tumor zone (R Tumor ), a 2-mm outer ring (R T+2 ), a 2-mm inner ring (R T-2 ), and a combined ring (R 2+2 ) on late arterial phase MRI images. Analysis of variance method (ANOVA) and least absolute shrinkage and selection operator (LASSO) algorithms were used for feature selection. Logistic regression with five-fold cross-validation was used for model construction. Receiver operating characteristic curves, calibrated curves, and decision curve analyses were used to assess model performance. DeLong tests were used to compare different models., Results: Twenty-nine desmoplastic and sixty-four non-desmoplastic CRLMs were included. The radiomic models achieved area under the curve (AUC) values of 0.736, 0.906, 0.804, and 0.794 for R Tumor , R T-2 , R T+2 , and R 2+2 , respectively, in the training cohorts. The AUC values were 0.713, 0.876, 0.785, and 0.777 for R Tumor , R T-2 , R T+2 , and R 2+2 , respectively, in the validation cohort. R T-2 exhibited the best performance., Conclusion: The MRI-based radiomic models could predict HGPs in CRLMs pre-operatively., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The bulk photovoltaic effect (BPVE) offers an interesting approach to generate a steady photocurrent in a single-phase material under homogeneous illumination, and it has been extensively investigated in ferroelectrics exhibiting spontaneous polarization that breaks inversion symmetry. Flexoelectricity breaks inversion symmetry via a strain gradient in the otherwise nonpolar materials, enabling manipulation of ferroelectric order without an electric field. Combining these two effects, we demonstrate active mechanical control of BPVE in suspended 2-dimensional CuInP 2 S 6 (CIPS) that is ferroelectric yet sensitive to electric field, which enables practical photodetection with an order of magnitude enhancement in performance. The suspended CIPS exhibits a 20-fold increase in photocurrent, which can be continuously modulated by either mechanical force or light polarization. The flexoelectrically engineered photodetection device, activated by air pressure and without any optimization, possesses a responsivity of 2.45 × 10 -2 A/W and a detectivity of 1.73 × 10 11 jones, which are superior to those of ferroelectric-based photodetection and comparable to those of the commercial Si photodiode.

Nanocomposites combining inorganic nanoparticles with high dielectric constant and polymers with high breakdown strength are promising for the high energy density storage of electricity, and carrier traps can significantly affect the dielectric breakdown process. Nevertheless, there still lacks direct experimental evidence on how nanoparticles affect the trap characteristics of nanocomposites, especially in a spatially resolved manner. Here, a technique is developed to image the trap distribution based on sequential Kelvin probe force microscopy (KPFM) in combination with the isothermal surface potential decay (ISPD) technique, wherein both shallow and deep trap densities and the corresponding energy levels can be mapped with nanoscale resolution. The technique is first validated using the widely-used commercial biaxially oriented polypropylene, yielding consistent results with macroscopic ISPD. The technique is then applied to investigate polyvinylidene fluoride-based nanocomposites filled with barium titanate nanoparticles, revealing higher deep trap density around surface-modified nanoparticles, which correlates well with its increased breakdown strength. This technique thus provides a powerful spatially resolved tool for understanding the microscopic mechanism of dielectric breakdown of nanocomposites., (© 2024 Wiley‐VCH GmbH.)

Fosmidomycin (FOS) is a natural product inhibiting the DXR enzyme in the MEP pathway and has stimulated interest for finding more suitable FOS analogues. Herein, two series of FOS analogue hydroxamate-containing bisphosphonates as proherbicides were designed, with bisphosphonate replacing the phosphonic unit in FOS while retaining the hydroxamate (BPF series) or replacing it with retro-hydroxamate (BPRF series). The BPF series were synthesized through a three-step reaction sequence including Michael addition of vinylidenebisphosphonate, N -acylation, and deprotection, and the BPRF series were synthesized with a retro-Claisen condensation incorporated into the reaction sequence. Evaluation on model plants demonstrated several compounds having considerable herbicidal activities, and in particular, compound 8m exhibited multifold activity enhancement as compared to the control FOS. The proherbicide properties were comparatively validated. Furthermore, DXR enzyme assay, dimethylallyl pyrophosphate rescue, and molecular docking verified 8m to be a promising proherbicide candidate targeting the DXR enzyme. In addition, 8m also displayed good antimalarial activities.

Clustered regularly interspaced short palindromic repeats and associated Cas protein (CRISPR-Cas), a powerful genome editing tool, has revolutionized gene function investigation and exhibits huge potential for clinical applications. CRISPR-Cas-mediated gene knockout has already become a routine method in research laboratories. However, in the last few years, accumulating evidences have demonstrated that genes knocked out by CRISPR-Cas may not be truly silenced. Functional residual proteins could be generated in such knockout organisms to compensate the putative loss of function, termed herein knockout escaping. In line with this, several CRISPR-Cas-mediated knockout screenings have discovered much less abnormal phenotypes than expected. How does knockout escaping happen and how often does it happen have not been systematically reviewed yet. Without knowing this, knockout results could easily be misinterpreted. In this review, we summarize these evidences and propose two main mechanisms allowing knockout escaping. To avoid the confusion caused by knockout escaping, several strategies are discussed as well as their advantages and disadvantages. On the other hand, knockout escaping also provides convenient tools for studying essential genes and treating monogenic disorders such as Duchenne muscular dystrophy, which are discussed in the end., (© 2024. The Author(s).)

The electrochemical performance of polyaniline-based all-gel-state supercapacitor (AGSSC) is significantly depended on the dispersity and mass loaded of polyaniline (PANI). In this manuscript, inspired by the properties of surfactant, sodium dodecylbenzene sulfonate (SDBS) was introduced to prepare various PANI-polyacrylamide/sodium alginate/SDBS (PANI y -PSS x ) AGSSCs. With presence of SDBS, the electrochemical performance of PANI y -PSS x AGSSCs was greatly improved, displaying a trend of initial rise and then decrease with increasing concentration of SDBS from 0 to 0.75 wt%. As the content of SDBS was 0.5 wt%, the resulting PANI 1.0 -PSS 0.5 AGSSC displayed the optimum electrochemical properties with area capacitance and energy density of 913.79 mF/cm 2 and 81.23 μWh/cm 2 , respectively. The capacitance rate of PANI 1.0 -PSS 0.5 AGSSC was still more than 93 % after 2000 cycles of sequential CV scans at the scan rate of 200 mV/s. These data were greatly higher than many reported PANI-based AGSSCs. Moreover, the resultant PANI 1.0 -PSS 0.5 AGSSC could maintain high electrochemical performance even after various operations, such as compression, puncture, fluctuating temperature, bending situations and various voltage windows and series-parallel connections. The resultant PANI 1.0 -PSS 0.5 AGSSC had the wide potentials to satisfy the real application requirements. This study offered a facile strategy for design and preparation of flexible supercapacitor with excellent electrochemical performance., Competing Interests: Declaration of competing interest The authors state that they are no competing financial interests or personal relationships influencing the work reported in this manuscript., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Accurate mitosis is coordinated by the spindle assembly checkpoint (SAC) through the mitotic checkpoint complex (MCC), which inhibits the anaphase-promoting complex or cyclosome (APC/C). As an essential regulator, Cdc20 promotes mitotic exit through activating APC/C and monitors kinetochore-microtubule attachment through activating SAC. Cdc20 requires multiple interactions with APC/C and MCC subunits to elicit these functions. Functionally assessing these interactions within cells requires efficient depletion of endogenous Cdc20, which is highly difficult to achieve by RNA interference (RNAi). Here we generated Cdc20 RNAi-sensitive cell lines which display a penetrant metaphase arrest by a single RNAi treatment. In this null background, we accurately measured the contribution of each known motif of Cdc20 on APC/C and SAC activation. The CRY box, a previously identified degron, was found critical for SAC by promoting MCC formation and its interaction with APC/C. These data reveal additional regulation within the SAC and establish a novel method to interrogate Cdc20., (© 2024. The Author(s).)

Eukaryotic cells are constantly exposed to various environmental stimuli. It remains largely unexplored how environmental cues bring about epigenetic fluctuations and affect heterochromatin stability. In the fission yeast Schizosaccharomyces pombe , heterochromatic silencing is quite stable at pericentromeres but unstable at the mating-type ( mat ) locus under chronic heat stress, although both loci are within the major constitutive heterochromatin regions. Here, we found that the compromised gene silencing at the mat locus at elevated temperature is linked to the phosphorylation status of Atf1, a member of the ATF/CREB superfamily. Constitutive activation of mitogen-activated protein kinase (MAPK) signaling disrupts epigenetic maintenance of heterochromatin at the mat locus even under normal temperature. Mechanistically, phosphorylation of Atf1 impairs its interaction with heterochromatin protein Swi6 HP1 , resulting in lower site-specific Swi6 HP1 enrichment. Expression of non-phosphorylatable Atf1, tethering Swi6 HP1 to the mat3M -flanking site or absence of the anti-silencing factor Epe1 can largely or partially rescue heat stress-induced defective heterochromatic maintenance at the mat locus., Competing Interests: LS, LL, CS, YW, QJ No competing interests declared, (© 2024, Sun, Liu, Song et al.)

Recent climate change has caused an increase in warming-driven erosion and sediment transport processes on the Tibetan Plateau (TP). Yet a lack of measurements hinders our understanding of basin-scale sediment dynamics and associated spatiotemporal changes. Here, using satellite-based estimates of suspended sediment, we reconstruct the quantitative history and patterns of erosion and sediment transport in major headwater basins from 1986 to 2021. Out of 13 warming-affected headwater regions, 63% of the rivers have experienced significant increases in sediment flux. Despite such intensified erosion, we find that 30% of the total suspended sediment flux has been temporarily deposited within rivers. Our findings reveal a pronounced spatiotemporal heterogeneity within and across basins. The recurrent fluctuations in erosion-deposition patterns within river channels not only result in the underestimation of erosion magnitude but also drive continuous transformations in valley morphology, thereby endangering local ecosystems, landscape stability, and infrastructure project safety., (© 2024. The Author(s).)

The Bub1 and BubR1 kinetochore proteins support proper chromosome segregation and mitotic checkpoint activity. Bub1 and BubR1 are paralogs with Bub1 being a kinase, while BubR1 localizes the PP2A-B56 protein phosphatase to kinetochores in humans. Whether this spatial separation of kinase and phosphatase activity is important is unclear as some organisms integrate both activities into one Bub protein. Here, we engineer human Bub1 and BubR1 proteins integrating kinase and phosphatase activities into one protein and show that these do not support normal mitotic progression. A Bub1-PP2A-B56 complex can support chromosome alignment but results in impairment of the checkpoint due to dephosphorylation of the Mad1 binding site in Bub1. Furthermore, a chimeric BubR1 protein containing the Bub1 kinase domain induces delocalized H2ApT120 phosphorylation, resulting in the reduction of centromeric hSgo2 and chromosome segregation errors. Collectively, these results argue that the spatial separation of kinase and phosphatase activities within the Bub complex is required for balancing its functions in the checkpoint and chromosome alignment., (© The Author(s) (2022). Published by Oxford University Press on behalf of Journal of Molecular Cell Biology, CEMCS, CAS.)

Rivers and streams are pivotal modulators in regional and global carbon cycles, but riverine CO 2 flux is still uncertain for permafrost watersheds. Here we present the seasonal CO 2 partial pressure (pCO 2 ) and CO 2 emission flux (FCO 2 ) of 8 rivers and streams in the Yangtze River source region (YRSR), which have high permafrost coverage and seasonally thawed active layer. The YRSR rivers and streams are generally supersaturated with CO 2 , although there are a few sites with CO 2 undersaturation during spring. The small headwater streams are CO 2 hot spots that show significantly higher pCO 2 (52 % higher) and FCO 2 (792 % higher) than larger rivers. Both pCO 2 and FCO 2 show distinct seasonality across the study sites. pCO 2 and FCO 2 peak in summer and exhibit much lower levels in autumn and spring, indicating that hot moments of riverine CO 2 occur in summer. Seasonal pCO 2 and FCO 2 variations are jointly controlled by hydrology, active layer dynamics and associated processes. The warm summer causes active layer thaw and highly active soil respiration, which release a large quantity of soil carbon and increase the CO 2 sources via strengthened hydrologic connectivity. The high rainfall and more thaw-released water in summer bring high discharge, which can increase the water velocity and gas exchange rate and thus CO 2 emission flux. Most of the variances of seasonal FCO 2 (95 %) can be explained by hydrology and active layer thaw depth. Nevertheless, the hydrological process and seasonally thawed active layer over Qinghai-Tibet Plateau (QTP) play crucial roles in riverine carbon export due to the summer monsoon-dominated climate in QTP. Our results suggest that full seasonal coverage of CO 2 dynamics is essential to quantify the annual CO 2 flux accurately. Changing climate and warming permafrost may alter the annual CO 2 emission due to deeper flow paths, hydrology changes, and longer emission windows throughout the year., Competing Interests: Declaration of competing interest The authors declare no conflict of interests., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Enhancing the peroxymonosulfate (PMS) activation efficiency to generate more radicals is vital to promote the Fenton-like reaction activity, however, how to promote the PMS adsorption and accelerate the interfacial electron transfer to boost its activation kinetics remains a great challenge. Herein, we prepared Cu-doped defect-rich In 2 O 3 (Cu-In 2 O 3 /O v ) catalysts containing asymmetric Cu-O v -In sites for PMS activation in water purification. The intrinsic catalytic activity is that the side-on adsorption configuration of the O-O bond (Cu-O-O-In) at the Cu-O v -In sites significantly stretches the O-O bond length. Meanwhile, the Cu-O v -In sites increase the electron density near the Fermi energy level, promoting more and faster electron transfer to the O-O bond for generating more SO 4 ⋅ - and ⋅OH. The degradation rate constant of tetracycline achieved by Cu-In 2 O 3 /O v is 31.8 times faster than In 2 O 3 /O v , and it shows the possibility of membrane reactor for practical wastewater treatment., (© 2023 Wiley-VCH GmbH.)