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The messenger RNA (mRNA) methylations in mammalian cells have been found to contain N6-methyladenosine (m6A), N6-2'-O-dimethyladenosine (m6Am), 7-methylguanosine (m7G), 1-methyladenosine (m1A), 5-methylcytosine (m5C), and 2'-O-methylation (2'-OMe). Their regulatory functions in control of mRNA fate and gene expression are being increasingly uncovered. To unambiguously understand the critical roles of mRNA methylations in physiological and pathological processes, mapping these methylations at single base resolution is highly required. Here, we will review the progresses made in methylation sequencing methodologies developed mainly in recent two years, with an emphasis on chemical labeling-assisted single base resolution methods, and discuss the problems and prospects as well.

● Pathogenic fungi are subject to DNA damage stress derived from host immune responses during infection. SUMO modification and precursor (pre)-mRNA splicing are both involved in DNA damage response (DDR). However the mechanisms of how SUMOylation and splicing coordinated in DDR remain largely unknown. ● Combining with biochemical analysis, RNA-seq method, and biological analysis, we report that SUMO pathway participates in DDR and virulence in Fusarium graminearum, a causal agent of Fusarium head blight of cereal crops worldwide. Interestingly, a key transcription factor FgSR is SUMOylated upon DNA damage stress. ● SUMOylation regulates FgSR nuclear-cytoplasmic partitioning and its phosphorylation by FgMec1, and promotes its interaction with chromatin remodeling complex SWI/SNF for activating the expression of DDR-related genes. Moreover, the SWI/SNF complex was found to further recruit splicing-related NineTeen Complex, subsequently modulates pre-mRNAs splicing during DDR. ● Our findings reveal a novel function of SUMOylation in DDR by regulating a transcription factor to orchestrate gene expression and pre-mRNA splicing to overcome DNA damage during the infection of F. graminearum, which advances the understanding of the delicate regulation of DDR by SUMOylation in pathogenic fungi, and extends the knowledge of cooperation of SUMOylation and pre-mRNA splicing in DDR in eukaryotes.

Förster resonant energy transfer between atoms separated at a distance of a few nanometers has strong relevance to different properties of matter. In this work, the resonant energy transfer rate is derived from the electric potential in a system with one dipole interacting with a separated 2D plane of dipoles. It shows an R−2 (R: distance between dipole and 2D plane of dipoles) dependency on the distance of dipole layers, which is different from previous theoretical evaluations with an R−4 dependency. The electroluminescence (EL) properties are studied in different rare earth (Re: Tm, Tb, Ho, Yb, Er) distributed single atomic layer doped Al2O3 nanolaminates prepared by atomic layer deposition, in which the distance between single atomic layers of Re3+ is modulated at the atomic scale. Our theoretical results are consistent with the changes of EL intensity and decay time with the distance between the single atomic rare earth doping layers. This result is crucial for increasing the accuracy in biosensing and design of photonic materials.

Pancreatic differentiation from human pluripotent stem cells (hPSCs) provides promising avenues for investigating development and treating diseases. N6-methyladenosine (m6A) is the most prevalent internal messenger RNA (mRNA) modification and plays pivotal roles in regulation of mRNA metabolism, while its functions remain elusive. Here, we profile the dynamic landscapes of m6A transcriptome-wide during pancreatic differentiation. Next, we generate knockout hPSC lines of the major m6A demethylase ALKBH5, and find that ALKBH5 plays significant regulatory roles in pancreatic organogenesis. Mechanistic studies reveal that ALKBH5 deficiency reduces the mRNA stability of key pancreatic transcription factors in an m6A and YTHDF2-dependent manner. We further identify that ALKBH5 cofactor α-ketoglutarate can be applied to enhance differentiation. Collectively, our findings identify ALKBH5 as an essential regulator of pancreatic differentiation and highlight that m6A modification-mediated mRNA metabolism presents an important layer of regulation during cell-fate specification and holds great potentials for translational applications.

DNA N6 -methyladenine (6mA) has recently received notable attention due to an increased finding of its functional roles in higher eukaryotes. Here we report an enzyme-assisted chemical labeling method to pinpoint the DNA 6mA methyltransferase (MTase) substrate modification site at single base resolution. A designed allyl-substituted MTase cofactor was applied in the catalytic transfer reaction, and the allyl group was installed to the N6 -position of adenine within a specific DNA sequence to form N6 -allyladenine (6aA). The iodination of 6aA allyl group induced the formation of 1, N6 -cyclized adenine which caused mutations during DNA replication by a polymerase. Thus the modification site could be precisely detected by a mutation signal. We synthesized 6aA deoxynucleoside and deoxynucleotide model compounds and a 6aA-containing DNA probe, and screened nine DNA polymerases to define an optimal system capable of detecting the substrate modification site of a DNA 6mA MTase at single-base resolution.

Here we report a simple and nonradioactive biochemical assay which is capable of accurately determining the substrate methylation sites of human RNA N6-methyladenosine methyltransferases METTL3/METTL14 and METTL16. This method employs enzyme-assisted chemical labelling of a specific base in an RNA substrate with the assistance of an allyl-substituted methyltransferase cofactor, and enables precise identification of the labelling site by a mutation signal from standard nucleic acid sequencing. Our method provides a platform to investigate the enzymatic methylations of long and structurally complex RNA substrates, and facilitates the discovery of new methyltransferases.

Based on the concepts of cloud water resource (CWR) and related variables proposed in the first part of this study, this paper provides details of two methods to quantify the CWR. One is diagnostic quantification (CWR-DQ) based on satellite observations, precipitation products, and atmospheric reanalysis data; and the other is numerical quantification (CWR-NQ) based on a cloud resolving model developed at the Chinese Academy of Meteorological Sciences (CAMS). The two methods are applied to quantify the CWR in April and August 2017 over North China, and the results are evaluated against all available observations. Main results are as follows. (1) For the CWR-DQ approach, reference cloud profiles are firstly derived based on the CloudSat/CALIPSO joint satellite observations for 2007–2010. The NCEP/NCAR reanalysis data in 2000–2017 are then employed to produce three-dimensional cloud fields. The budget/balance equations of atmospheric water substance are lastly used, together with precipitation observations, to retrieve CWR and related variables. It is found that the distribution and vertical structure of clouds obtained by the diagnostic method are consistent with observations. (2) For the CWR-NQ approach, it assumes that the cloud resolving model is able to describe the cloud microphysical processes completely and precisely, from which four-dimensional distributions of atmospheric water vapor, hydrometeors, and wind fields can be obtained. The data are then employed to quantify the CWR and related terms/quantities. After one-month continuous integration, the mass of atmospheric water substance becomes conserved, and the tempospatial distributions of water vapor, hydrometeors/cloud water, and precipitation are consistent with observations. (3) Diagnostic values of the difference in the transition between hydrometeors and water vapor (Cvh − Chv) and the surface evaporation (Es) are well consistent with their numerical values. (4) Correlation and bias analyses show that the diagnostic CWR contributors are well correlated with observations, and match their numerical counterparts as well, indicating that the CWR-NQ and CWR-DQ methods are reasonable. (5) Underestimation of water vapor converted from hydrometeors (Chv) is a shortcoming of the CWR-DQ method, which may be rectified by numerical quantification results or by use of advanced observations on higher spatiotemporal resolutions.

AIMS: Soil dissolved organic carbon (DOC) is a primary form of labile carbon in terrestrial ecosystems, and therefore plays a vital role in soil carbon cycling. This study aims to quantify the budgets of soil DOC at biome and global levels and to examine the variations in soil DOC and their environmental controls. LOCATION: Global. TIME PERIOD: 1981–2019. METHODS: We compiled a global dataset and analysed the concentration and distribution of DOC across 10 biomes. RESULTS: Large variations in DOC are found among biomes across space and the soil DOC concentration declines exponentially along soil depths. Tundra has the highest soil DOC concentration in 0–30 cm soils [453.75 (95% confidence interval: 324.95–633.5) mg/kg], whereas tropical and temperate forests have relatively lower DOC concentrations, ranging from 30.20 (24.78–36.80) to 54.54 (49.77–59.77) mg/kg. DOC generally accounts for

Transcriptome-wide mapping of N6-methyladenosine (m6A) at base resolution remains an issue, impeding our understanding of m6A roles at the nucleotide level. Here, we report a metabolic labeling method to detect mRNA m6A transcriptome-wide at base resolution, called ‘m6A-label-seq’. Human and mouse cells could be fed with a methionine analog, Se-allyl-l-selenohomocysteine, which substitutes the methyl group on the enzyme cofactor SAM with the allyl. Cellular RNAs could therefore be metabolically modified with N6-allyladenosine (a6A) at supposed m6A-generating adenosine sites. We pinpointed the mRNA a6A locations based on iodination-induced misincorporation at the opposite site in complementary DNA during reverse transcription. We identified a few thousand mRNA m6A sites in human HeLa, HEK293T and mouse H2.35 cells, carried out a parallel comparison of m6A-label-seq with available m6A sequencing methods, and validated selected sites by an orthogonal method. This method offers advantages in detecting clustered m6A sites and holds promise to locate nuclear nascent RNA m6A modifications. The authors developed a metabolic labeling method via incorporation of allyl-SAM analogs to profile transcriptome-wide m6A at base resolution, which enables identification of m6A motifs and clustered m6A sites.

Summary We describe here a metabolic labeling protocol for detecting cellular transcriptome-wide mRNA N6-methyladenosine (m6A) at base resolution. By feeding cells an analog of methionine, potential mRNA m6A forming sites are replaced with the N6-allyladenosine (a6A). A mild chemical iodination of a6A in RNA results in its opposite base misincorporation during RNA reverse transcription, and thus m6A locations could be precisely identified in the high-throughput sequencing. m6A-label-seq provides a strategy to label and identify cellular epitranscriptomic modification sites. For complete details on the use and execution of this profile, please refer to Shu et al., 2020., Graphical abstract, Highlights • Detection of cellular mRNA m6A modification sites at single base resolution • m6A-forming site labeling via an allyl-substituted methyltransferase cofactor • Replacement of RNA m6A by N6-allyl adenosine via RNA metabolism • N6-allyl adenosine is a chemical sequencing nucleoside analog, We describe here a metabolic labeling protocol for detecting cellular transcriptome-wide mRNA N6-methyladenosine (m6A) at base resolution. By feeding cells an analog of methionine, potential mRNA m6A forming sites are replaced with the N6-allyladenosine (a6A). A mild chemical iodination of a6A in RNA results in its opposite base misincorporation during RNA reverse transcription, and thus m6A locations could be precisely identified in the high-throughput sequencing. m6A-label-seq provides a strategy to label and identify cellular epitranscriptomic modification sites.

Pancreatic differentiation from human pluripotent stem cells (hPSCs) provides promising avenues for investigating development and treating diseases. N

Primary cilia are antenna-like subcellular structures to act as signaling platforms to regulate many cellular processes and embryonic development. m

Tumor-associated macrophages (TAMs) that exist in tumor microenvironment promote tumor progression and have been suggested as a promising therapeutic target for cancer therapy in preclinical studies. Development of theranostic systems capable of specific targeting, imaging, and ablation of TAMs will offer clinical benefits. Here we constructed a theranostic probe, namely, TPE-Man, by attaching mannose moieties to a red-emissive and AIE (aggregation-induced emission)-active photosensitizer. TPE-Man can specifically recognize a mannose receptor that is overexpressed on TAMs by the sugar-receptor interaction and enables fluorescent visualization of the mannose-receptor-positive TAMs in high contrast. The histologic study of mouse tumor sections further verifies TPE-Man's excellent targeting specificity being comparable with the commercial mannose-receptor antibody. TAMs can be effectively eradicated upon exposure to white light irradiation via a photodynamic therapy effect. To our knowledge, this is the first small molecular theranostic probe for TAMs that revealed combined advantages of low cost, high targeting specificity, fluorescent light-up imaging, and efficient photodynamic ablation.

Here we report a combined fluorescence and mass spectrometry assay which is capable of stably visualizing and quantifying cellular nucleoside-labeled RNA production and degradation. The fluorescence and mass spectrometry signals from cellular labeled RNAs show a linear correlation. This simple and robust assay benefits the biological community to study RNA metabolism.

Summary: Transcriptional regulation of circadian rhythms is essential for lipid metabolic homeostasis, disruptions of which can lead to metabolic diseases. Whether N6-methyladenosine (m6A) mRNA methylation impacts circadian regulation of lipid metabolism is unclear. Here, we show m6A mRNA methylation oscillations in murine liver depend upon a functional circadian clock. Hepatic deletion of Bmal1 increases m6A mRNA methylation, particularly of PPaRα. Inhibition of m6A methylation via knockdown of m6A methyltransferase METTL3 decreases PPaRα m6A abundance and increases PPaRα mRNA lifetime and expression, reducing lipid accumulation in cells in vitro. Mechanistically, YTHDF2 binds to PPaRα to mediate its mRNA stability to regulate lipid metabolism. Induction of reactive oxygen species both in vitro and in vivo increases PPaRα transcript m6A levels, revealing a possible mechanism for circadian disruption on m6A mRNA methylation. These data show that m6A RNA methylation is important for circadian regulation of downstream genes and lipid metabolism, impacting metabolic outcomes. : Zhong et al. reveal that hepatic Bmal1 deletion changes m6A mRNA methylation, particularly of PPaRα. METTL3 or YTHDF2 knockdown affects PPaRα transcription and translation, impacting downstream lipid metabolism. These findings further reveal the overlap between circadian gene network disruption, mRNA m6A modifications, and metabolic state. Keywords: circadian clock, Bmal1, hepatic, lipid metabolism, ROS, m6A RNA methylation, post-transcriptional regulation, METTL3, YTHDF2, PPaRα

DNA N

Synthetic modified messenger RNA (mRNA) has manifested great potentials for therapeutic applications such as vaccines and gene therapies, with the recent mRNA vaccines for global pandemic COVID-19 (corona virus disease 2019) attracting the tremendous attention. The chemical modifications and delivery vehicles of synthetic mRNAs are the two key factors for their in vivo therapeutic applications. Chemical modifications like nucleoside methylation endow the synthetic mRNAs with high stability and reduced stimulation of innate immunity. The development of scalable production of synthetic mRNA and efficient mRNA formulation and delivery strategies in recent years have remarkably advanced the field. It is worth noticing that we had limited knowledge on the roles of mRNA modifications in the past. However, the last decade has witnessed not only new discoveries of several naturally occurring mRNA modifications but also substantial advances in understanding their roles on regulating gene expression. It is highly necessary to reconsider the therapeutic system made by synthetic modified mRNAs and delivery vectors. In this review, we will mainly discuss the roles of various chemical modifications on synthetic mRNAs, briefly summarize the progresses of mRNA delivery strategies, and highlight some latest mRNA therapeutics applications including infectious disease vaccines, cancer immunotherapy, mRNA-based genetic reprogramming and protein replacement, mRNA-based gene editing. Statement of significance The development of synthetic mRNA drug holds great promise but lies behind small molecule and protein drugs largely due to the challenging issues regarding its stability, immunogenicity and potency. In the last 15 years, these issues have beensubstantially addressed by synthesizing chemically modified mRNA and developing powerful delivery systems; the mRNA therapeutics has entered an exciting new era begun with the approved mRNA vaccines for the COVID-19 infection disease. Here, we provide recent progresses in understanding the biological roles of various RNA chemical modifications, in developing mRNA delivery systems, and in advancing the emerging mRNA-based therapeutic applications, with the purpose to inspire the community to spawn new ideas for curing diseases., Graphical Abstract Image, graphical abstract

Silicon-based Yb-doped Y

This paper conducted several experimental tests and theoretical analyses to present a comprehensive study on the behavior of dry-connected steel plate frame-reinforced brick walls under axial compression. One unreinforced brick wall, two brick walls reinforced with dry-connected steel plate frame, and one brick wall reinforced with steel strips were fabricated for axial compression tests. The experiments generally showed that steel plate frames effectively improved the structure's bearing capacity and axial stiffness and impeded its cracking. Increasing the thickness of steel plates further improved the bearing capacity but undermined the ductility of the composite wall. Besides, based on the buckling theory of steel plate and the existing calculation theory of masonry strength, this paper also proposed formulas for determining the bearing capacity of the composite wall. The calculations of formulas exhibited acceptable accuracy in comparison with the experimental results.

Non-enzymatic degradation of wood via a chelator-mediated Fenton (CMF) system is the primary method for initial attack in brown rot fungal decomposition of wood, the most common type of fungal degradation of terrestrial carbon biomass on the planet. In this study, the degradation of thin films of cellulose and chitin by a CMF system was investigated and compared to enzymatic hydrolysis. The kinetics of the rapid cellulose and chitin deconstruction and the morphologies of the degraded cellulose and chitin surfaces were studied by quartz crystal microbalance with dissipation monitoring (QCM-D) and atomic force microscopy (AFM), respectively. The QCM-D results quantitatively indicated that ~90 wt% of the regenerated cellulose or chitin was capable of being deconstructed by CMF action alone. While enzymatic degradation was consistent with stripping of layers from the surface of the cellulose or chitin films, the CMF process exhibited a pronounced two stage process with a rapid initial depolymerization throughout the films. The initial degradation rates for both model surfaces by the CMF system were faster than enzyme action. This research suggests that the CMF process should be applicable for the deconstruction of a wide variety of polysaccharides over Fenton chemistry alone.

Supplementary Figures

Single image super-resolution (SISR) aims to recover the high-resolution (HR) image from its low-resolution (LR) input image. With the development of deep learning, SISR has achieved great progress. However, It is still a challenge to restore the real-world LR image with complicated authentic degradations. Therefore, we propose FAN, a frequency aggregation network, to address the real-world image super-resolu-tion problem. Specifically, we extract different frequencies of the LR image and pass them to a channel attention-grouped residual dense network (CA-GRDB) individually to output corresponding feature maps. And then aggregating these residual dense feature maps adaptively to recover the HR image with enhanced details and textures. We conduct extensive experiments quantitatively and qualitatively to verify that our FAN performs well on the real image super-resolution task of AIM 2020 challenge. According to the released final results, our team SR-IM achieves the fourth place on the X4 track with PSNR of 31.1735 and SSIM of 0.8728.

N6-methyladenosine (m6A) messenger RNA methylation is a gene regulatory mechanism affecting cell differentiation and proliferation in development and cancer. To study the roles of m6A mRNA methylation in cell proliferation and tumorigenicity, we investigated human endometrial cancer in which a hotspot R298P mutation is present in a key component of the methyltransferase complex (METTL14). We found that about 70% of endometrial tumours exhibit reductions in m6A methylation that are probably due to either this METTL14 mutation or reduced expression of METTL3, another component of the methyltransferase complex. These changes lead to increased proliferation and tumorigenicity of endometrial cancer cells, likely through activation of the AKT pathway. Reductions in m6A methylation lead to decreased expression of the negative AKT regulator PHLPP2 and increased expression of the positive AKT regulator mTORC2. Together, these results reveal reduced m6A mRNA methylation as an oncogenic mechanism in endometrial cancer and identify m6A methylation as a regulator of AKT signalling.

Facile preparation and UV stabilization of electrospun poly(e-caprolactone) (PCL)/2-methyl-3-(trimethoxysilyl) propylester (M8POSS)/pentaerythritol tetrakis(3-mercaptopropionate) (PETM) composite fibers via thiol-ene click reaction were investigated. The morphological studies clearly showed the M8POSS and PETM macromers were excluded from PCL crystalline phase during electrospinning. The cross-linking reaction occurs in the amorphous phase of PCL fibers and possibly the fiber surface. By locking amorphous PCL chains into the cross-linked M8POSS and PETM through thiol-ene click reaction, we are able to fabricate PCL/POSS composite fibers, which can remain structural stability under UVC for longer period of time. The facile fabrication of the composite fibers via thiol-ene click reaction reported here provided valuable insight into not only the surface coating of medical devices but also new biocompatible composite materials.

N6-methyladenosine (m6A) is enriched in 3′untranslated region (3′UTR) and near stop codon of mature polyadenylated mRNAs in mammalian systems and has regulatory roles in eukaryotic mRNA transcriptome switch. Significantly, the mechanism for this modification preference remains unknown, however. Herein we report a characterization of the full m6A methyltransferase complex in HeLa cells identifying METTL3/METTL14/WTAP/VIRMA/HAKAI/ZC3H13 as the key components, and we show that VIRMA mediates preferential mRNA methylation in 3′UTR and near stop codon. Biochemical studies reveal that VIRMA recruits the catalytic core components METTL3/METTL14/WTAP to guide region-selective methylations. Around 60% of VIRMA mRNA immunoprecipitation targets manifest strong m6A enrichment in 3′UTR. Depletions of VIRMA and METTL3 induce 3′UTR lengthening of several hundred mRNAs with over 50% targets in common. VIRMA associates with polyadenylation cleavage factors CPSF5 and CPSF6 in an RNA-dependent manner. Depletion of CPSF5 leads to significant shortening of 3′UTR of over 2800 mRNAs, 84% of which are modified with m6A and have increased m6A peak density in 3′UTR and near stop codon after CPSF5 knockdown. Together, our studies provide insights into m6A deposition specificity in 3′UTR and its correlation with alternative polyadenylation.

Metal–organic frameworks (MOFs) have shown great promise as efficient CO2 adsorbents, as well as an emerging class of heterogeneous catalysts for conversion of CO2 to other useful chemicals. In this work, we synthesized and characterized two isostructural hafnium-based MOFs, denoted as Hf-VPI-100 (Cu) and Hf-VPI-100 (Ni). Both frameworks demonstrated high catalytic efficiency for cycloaddition of CO2 to epoxides under ambient pressure. In situ PXRD, QCM and DRIFTs have been used to probe the interaction between the guest molecules (CO2/epoxide) and Hf-VPI-100. The crystal structures of these frameworks were preserved during the exposure to CO2 atmosphere up to 20 bar. The epoxide uptake per unit cell of VPI-100 and diffusion coefficients have been calculated by QCM analysis. Comparison of catalytic efficiency between Hf-VPI-100 and the previously reported Zr-based VPI-100, aided by electronic structure calculations revealed that the open metal centers in the metallocyclam act as the primary Lewis acid sites to facilitate the catalytic conversion of CO2.

Differentiating between live and dead cells is a critical step for biological researchers, clinical doctors and pharmaceutical engineers when evaluating cell viability, for determining compound cytotoxicity and in the development of effective treatments for many diseases. Usually, careful selection and combination of two different dyes are required to differentiate and image both live and dead cells. In this work, we present a new method that can differentiate, quantify and image both live and dead cells concurrently through the use of a single, cell-permeable, biochromic fluorescent dye. Two silole-based hemicyanine dyes, Silo-Cy and Silo-2Cy are designed and synthesized. These dyes exhibit green fluorescence in both live and dead cells but much stronger green and red fluorescence only from dead cells. By collecting signals from the two distinct channels, we are able to image and discriminate between live and dead cells through fluorescence microscopy and quantify the cell viability via flow cytometry.

A theranostic drug delivery system composed of tetraphenyl-ethene (AIEgen), benzyl boronic ester (trigger), and doxorubicin (drug) was designed and synthesized; its utilities for cell imaging, drug delivery tracking, and cancer cell cytociding were evaluated.

This paper conducted experimental tests and theoretical analyses to present a comprehensive study on the shear behavior of dry-connected steel plate frame-reinforced brick walls. One unreinforced brick wall, one brick wall reinforced with steel strips, and four brick walls reinforced with dry-connected steel plate frames were fabricated for shear compression tests. Experimental tests showed that steel plate frames effectively improved the bearing capacity and stiffness of masonry structures and impeded cracking. As expected, enhancing the steel plate thickness and vertical load boosted the peak load and axial stiffness of steel frame-reinforced structures but also reduced the ductility. Numerical simulation accurately predicted the peak load, crack development, and crushing area of the specimens. In addition, based on the buckling theory of steel plates and the existing calculation theory of masonry, this paper also proposed formulas for determining the bearing capacity of composite walls. The calculations of the formulas exhibited high accuracy in comparison with the experimental results.

Atmospheric water demand is practically characterized as vapor pressure deficit (VPD) and has been identified as a critical driver of ecosystem function, by affecting plant mortality, wildfires, and carbon loss. In this study, we used daily eddy covariance data across Chinese forest, grassland and shrubland ecosystems, in combination with remote sensing data, to investigate the impacts of VPD on gross primary productivity (GPP). We found divergent VPD impacts on GPP among grassland, shrubland and forest ecosystems. The VPD yielded substantial inhibitory impacts on GPP in grassland ecosystems and this suppressing impact was regulated by soil water content (SWC), showing that GPP declined with VPD under dry conditions but increased with VPD under wet conditions. This GPP variance was attributed to VPD, SWC and their interactions. More than 50% of the variability in GPP was explained by SWC in grassland ecosystems and by VPD in forest and shrubland ecosystems. Partial correlation analysis, random forest, and multiple linear regression revealed similar results when temperature, radiation and SWC were considered. Compared with shrubland and forest ecosystems, grassland has drier environmental conditions and poorer soil water-holding capacity that led to lower SWC and stronger negative impacts on VPD. Thus, GPP was susceptible to the negative impacts of higher VPD, especially under dryness stress. Our results highlight the need to comprehensively consider divergent VPD impacts for different ecosystems to more accurately assess climate impacts on ecosystem function.

Wetlands store approximately one-third of soil carbon (C) in terrestrial ecosystems, and the loss of C in wetlands has been accelerated by reclamation. However, how wetland reclamation affects microbial properties along soil profiles remains unclear. In this study, we sampled 100 cm soil cores from a wetland and an adjacent cropland that has been cultivated for 23 years to evaluate the impacts of land conversion on soil microbial community structure and soil element concentrations in the Sanjiang Plain, Northeastern China. The C and nitrogen (N) concentrations in microbial biomass declined exponentially with depth in both the wetland and cropland with different magnitudes. Continuous cultivation for 23 years tended to homogenized C, N, phosphorus (P), and sulfur (S) contents in soils and microbial biomass along the soil profile. Compared with the wetland, C and N in cropland soils were lower, and microbial biomass C, N, P and S were lower in surface soils (0–30 cm), while higher in both middle soils (40–70 cm) and deep soils (70–100 cm). Cultivation narrowed the C:N:P:S stoichiometry in soils and microbial biomass, with large changes in surface soils and minor changes in deep soils. The Bray-Curtis dissimilarity test confirmed the large changes in surface soils while minor changes in deep soils. After 23-years of cultivation the abundances of fungi and bacteria were significantly reduced by approximately 90% and 78% in surface soils, but the bacterial abundance was enhanced by approximately 2–3 times in middle soils, leading to a decreasing fungi:bacteria ratio along soil profile in cropland. Soil TC and pH were the predominant factors controlling the microbial composition in wetland. The homogenizing impact of wetland reclamation on microbial properties along soil profiles suggests the different responses of microbial and soil elements to human activities, indicating a critical need of differentiating microbes from soils when examining soil elements under a changing environment.

The net ecosystem CO2 exchange (NEE) is a critical parameter for quantifying terrestrial ecosystems and their contributions to the ongoing climate change. The accumulation of ecological data is calling for more advanced quantitative approaches for assisting NEE prediction. In this study, we applied two widely used machine learning algorithms, Random Forest (RF) and Extreme Gradient Boosting (XGBoost), to build models for simulating NEE in major biomes based on the FLUXNET dataset. Both models accurately predicted NEE in all biomes, while XGBoost had higher computational efficiency (6~62 times faster than RF). Among environmental variables, net solar radiation, soil water content, and soil temperature are the most important variables, while precipitation and wind speed are less important variables in simulating temporal variations of site-level NEE as shown by both models. Both models perform consistently well for extreme climate conditions. Extreme heat and dryness led to much worse model performance in grassland (extreme heat: R2 = 0.66~0.71, normal: R2 = 0.78~0.81; extreme dryness: R2 = 0.14~0.30, normal: R2 = 0.54~0.55), but the impact on forest is less (extreme heat: R2 = 0.50~0.78, normal: R2 = 0.59~0.87; extreme dryness: R2 = 0.86~0.90, normal: R2 = 0.81~0.85). Extreme wet condition did not change model performance in forest ecosystems (with R2 changing −0.03~0.03 compared with normal) but led to substantial reduction in model performance in cropland (with R2 decreasing 0.20~0.27 compared with normal). Extreme cold condition did not lead to much changes in model performance in forest and woody savannas (with R2 decreasing 0.01~0.08 and 0.09 compared with normal, respectively). Our study showed that both models need training samples at daily timesteps of >2.5 years to reach a good model performance and >5.4 years of daily samples to reach an optimal model performance. In summary, both RF and XGBoost are applicable machine learning algorithms for predicting ecosystem NEE, and XGBoost algorithm is more feasible than RF in terms of accuracy and efficiency.

In the search for a transformative new energy storage system, the rechargeable Li/sulfur battery is considered as one of the promising candidates due to its much higher energy density and lower cost than state-of-the-art lithium-ion batteries. However, the insulating nature of sulfur and the dissolution of intermediary polysulfides into the electrolyte significantly hinder its practical application. Very recently, selenium and selenium–sulfur systems have received considerable attention as cathode materials for rechargeable batteries owing to the high electronic conductivity (20 orders of magnitude higher than sulfur) and high volumetric capacity (3254 mAh/cm3) of selenium. In this Perspective, we present an overview of the implications of employing selenium and selenium–sulfur systems with different structures and compositions as electroactive materials for rechargeable lithium batteries. We also show how the cathode structures, electrolytes, and electrode–electrolyte interfaces affect the electrochemist...

Cathode materials are critical to the energy density, power density and safety of sodium-ion batteries (SIBs). Herein, we performed a comprehensive study to elucidate and exemplify the interplay mechanism between phase structures, interfacial microstrain and electrochemical properties of layered-structured NaxNi1/3Co1/3Mn1/3O2 cathode materials for high voltage SIBs. The electrochemical test results showed that NaxNi1/3Co1/3Mn1/3O2 with an intergrowth P2/O3/O1 structure demonstrates better electrochemical performance and better thermal stability than NaxNi1/3Co1/3Mn1/3O2 with P2/O3 binary-phase integration and NaxNi1/3Co1/3Mn1/3O2 where only the P phase is dominant. This result is caused by the distinct interfacial microstrain development during the synthesis and cycling of the P2/O3/O1 phase. In operando high energy X-ray diffraction further revealed that the intergrowth P2/O1/O3 cathode can inhibit the irreversible P2–O2 phase transformation and simultaneously improve the structure stability of the O3 and O1 phases during cycling. We believe that interfacial microstrain can serve as an indispensable bridge to guide future design and synthesis of high performance SIB cathode materials and other high energy battery materials.

Soil water shortage is a critical issue for the Southwest US (SWUS), the typical arid region that has experienced severe droughts over the past decades, primarily caused by climate change. However, it is still not quantitatively understood how soil water storage in the SWUS is affected by climate change. We integrated the time-series data of water storage and evapotranspiration derived from satellite data, societal water consumption, and meteorological data to quantify soil water storage changes and their climate change impacts across the SWUS from 2003 to 2014. The water storage decline was found across the entire SWUS, with a significant reduction in 98.5% of the study area during the study period. The largest water storage decline occurred in the southeastern portion, while only a slight decline occurred in the western and southwestern portions of the SWUS. Net atmospheric water input could explain 38% of the interannual variation of water storage variation. The climate-change-induced decreases in net atmospheric water input predominately controlled the water storage decline in 60% of the SWUS (primarily in Texas, Eastern New Mexico, Eastern Arizona, and Oklahoma) and made a partial contribution in approximately 17% of the region (Central and Western SWUS). Climate change, primarily as precipitation reduction, made major contributions to the soil water storage decline in the SWUS. This study infers that water resource management must consider the climate change impacts over time and across space in the SWUS.

Precursor messenger RNA (pre-mRNA) splicing is an essential and tightly regulated process in eukaryotic cells; however, the regulatory mechanisms for the splicing are not well understood. Here, we characterize a RNA binding protein named FgRbp1 in Fusarium graminearum, a fungal pathogen of cereal crops worldwide. Deletion of FgRbp1 leads to reduced splicing efficiency in 47% of the F. graminearum intron-containing gene transcripts that are involved in various cellular processes including vegetative growth, development, and virulence. The human ortholog RBM42 is able to fully rescue the growth defects of ΔFgRbp1. FgRbp1 binds to the motif CAAGR in its target mRNAs, and interacts with the splicing factor FgU2AF23, a highly conserved protein involved in 3’ splice site recognition, leading to enhanced recruitment of FgU2AF23 to the target mRNAs. This study demonstrates that FgRbp1 is a splicing regulator and regulates the pre-mRNA splicing in a sequence-dependent manner in F. graminearum. Human RBM42 associates with the spliceosome complex. Here the authors show that the fungus counterpart of RBM42, FgRbp1 regulates splicing by interacting with FgU2AF23.

N6-Methyladenosine (m6A) modification has been implicated in the progression of several cancers. We reveal that during epithelial-mesenchymal transition (EMT), one important step for cancer cell metastasis, m6A modification of mRNAs increases in cancer cells. Deletion of methyltransferase-like 3 (METTL3) down-regulates m6A, impairs the migration, invasion and EMT of cancer cells both in vitro and in vivo. m6A-sequencing and functional studies confirm that Snail, a key transcription factor of EMT, is involved in m6A-regulated EMT. m6A in Snail CDS, but not 3’UTR, triggers polysome-mediated translation of Snail mRNA in cancer cells. Loss and gain functional studies confirm that YTHDF1 mediates m6A-increased translation of Snail mRNA. Moreover, the upregulation of METTL3 and YTHDF1 act as adverse prognosis factors for overall survival (OS) rate of liver cancer patients. Our study highlights the critical roles of m6A on regulation of EMT in cancer cells and translation of Snail during this process., RNA m6A methylation is known to be dysregulated in many cancers. Here, the authors show that m6A methylation of Snail mRNA regulates its translation with potential effects on epithelial mesenchymal transition.

Previous studies have indicated a positive relationship between self-compassion and psychological and emotional well-being in chronic pain populations. However, evidence on the role and mechanisms of self-compassion in pain perception is largely limited. The current study was designed to investigate the effects and a potential mechanism of self-compassion on experimental pain. Thirty healthy participants underwent a compassionate self-talk protocol, which was followed by cold pain exposure during which high-frequency heart rate variability (HF-HRV) was evaluated. The compassionate self-talk protocol successfully generated compassionate statements among the participants. Our behavioral data showed lower pain ratings in the self-compassion compared to the control condition. Moreover, self-compassion manipulation resulted in higher HF-HRV during pain, which was associated with lower pain ratings. We present interesting findings that a short period of compassionate self-talk may decrease experimental pain as well as mechanistic evidence surrounding bodily control over pain-related arousal indicated by HF-HRV. PERSPECTIVE: This study presents the first line of evidence that a short period of compassionate self-talk may be sufficient to reduce experimental pain. We also demonstrate increased bodily control as a potential mechanism underlying this effect.

Silicon-based Yb-doped Y3Al5O12 garnet nanofilms are fabricated by atomic layer deposition, which are polycrystalline after annealing at 1150 °C. The sub-nanometer compositional regulation and the Yb2O3 cladding layers, which also work as the luminescent dopants, are critical for the crystallization. Characteristic Yb3+ luminescence at 1030 nm and 970 nm is identified under electrical injection, exhibiting the external quantum efficiency of 0.65% and the fluorescence lifetime of 80-200 µs. The doped Yb3+ are impact-excited by hot electrons stemming from Fowler-Nordheim tunneling mechanism within the Y3Al5O12 matrix, with the excitation cross section of 0.7×10−15 to 6.4×10−15 cm2. This work certifies the manipulation of multi-oxide nanofilms with designed composition and crystallinity, revealing the possibility of developing Si-based optoelectronic devices from crystalline garnet films.

DNA N6-methyldeoxyadenosine (6mA) is a well-known prokaryotic DNA modification that has been shown to exist and play epigenetic roles in eukaryotic DNA. Here we report that 6mA accumulates up to ∼0.1–0.2% of total deoxyadenosine during early embryogenesis of vertebrates, but diminishes to the background level with the progression of the embryo development. During this process a large fraction of 6mAs locate in repetitive regions of the genome., DNA 6mA is a poorly understood epigenetic mark present at a low abundance in eukaryotic genomes. Here the authors observe high levels in zebrafish and pig during early embryogenesis enriched to repetitive regions of the genome and followed by attenuation during development.

Cationic derivatives of cellulose and other polysaccharides are attractive targets for biomedical applications due to their propensity for electrostatically binding with anionic biomolecules, such as nucleic acids and certain proteins. To date, however, relatively few practical synthetic methods have been described for their preparation. Herein, we report a useful and efficient strategy for cationic cellulose ester salt preparation by the reaction of 6-bromo-6-deoxycellulose acetate with pyridine or 1-methylimidazole. Dimethyl sulfoxide solvent favored this displacement reaction to produce cationic cellulose acetate derivatives, resulting in high degrees of substitution (DS) exclusively at the C-6 position. These cationic cellulose derivatives bearing substantial, permanent positive charge exhibit surprising thermal stability, dissolve readily in water, and bind strongly with a hydrophilic and anionic surface, supporting their potential for a variety of applications such as permeation enhancement, mucoadhesion, and gene or drug delivery. Expanding upon this chemistry, we reacted a 6-imidazolyl-6-deoxycellulose derivative with 1,3-propane sultone to demonstrate the potential for further elaboration to regioselectively substituted zwitterionic cellulose derivatives.