Unveiling evapotranspiration patterns and energy balance in a subalpine forest of the Qinghai-Tibet Plateau:observations and analysis from an eddy covariance system

Evapotranspiration is an important parameter used to characterize the water cycle of ecosystems.To under-stand the properties of the evapotranspiration and energy balance of a subalpine forest in the southeastern Qinghai-Tibet Plateau,an open-path eddy covariance system was set up to monitor the forest from November 2020 to October 2021 in a core area of the Three Parallel Rivers in the Qing-hai-Tibet Plateau.The results show that the evapotranspira-tion peaked daily,the maximum occurring between 11:00 and 15:00.Environmental factors had significant effects on evapotranspiration,among them,net radiation the greatest(R^(2)=0.487),and relative humidity the least(R^(2)=0.001).The energy flux varied considerably in different seasons and sensible heat flux accounted for the main part of turbulent energy.The energy balance ratio in the dormant season was less than that in the growing season,and there is an energy imbalance at the site on an annual time scale.

Roof filling control technology and application to mine roadway damage in small pit goaf

To recover coal resources that have been damaged by traditional mining methods and ensure stability of the lower roadway in a small pit goaf,the goaf area must be filled and reinforced.In this research,the 1202 working face of the Hanzui mine is considered as an example for classifying the roof of the mining tunnel under the small kiln destruction zone,the effect of the goaf on the roadway is determined based on the radio tunnel penetration method,a mechanical model to determine the roof filling control mechanism was established,and the duct foaming system and roof filling process were designed.The results show that the scope and degree of influence of the goaf on the mining lane are large,but safe tunneling can be ensured through the use of a steel shed and advanced grouting techniques.When the roof conditions are not similar,materials with different filling heights and filling strengths can be used to control the roof filling of the roadway.By combining field experience and laboratory tests,it was determined that a high-foaming material with a water-cement ratio of 1:0.6,a suitable high-foaming additive,and a water volume ratio of 1:30 is cost-efficient for filling and meets the filling strength requirements.Finally,the reliability of the proposed technology was verified by field experiments,which provide a reference for filling operations in similar mines.

Effects of Different Storage Methods and Storage Time on the Quality of Codonopsis pilosula

[Objectives]To study the effects of different storage methods and storage time on the quality of Codonopsis pilosula.[Methods]Experiment was performed by setting three different storage methods and times.[Results]When stored for 12 months,the extract content in the natural storage,conventional sealing,and controlled atmosphere storage was slightly lower than 77.32%before storage,and decreased by 2.82%,3.62%,and 1.71%,respectively.When stored for 18 months,the extract content was 74.14%,73.21%,and 72.08%,decreased by 4.11%,5.31%,and 6.78%,respectively compared with that before storage,all of which met the specified content in Chinese Pharmacopoeia.[Conclusions]The three storage times had significant effects on moisture and extract content of C.pilosula,but had no significant effects on atractylenolide III.With the extension of storage time,the moisture,extract,and content declined,so the storage time theoretically should not exceed 12 months.

Effects of Different Seedling Grades on Yield and Commercial Quality of Codonopsis pilosula

[Objectives] This study was conducted to further explore the yield increasing potential of Codonopsis pilosula, and to seek seedlings suitable for efficient production of C. pilosula. [Methods] The effects of C. pilosula seedlings of different sizes on root yield and commercial quality under different cultivation densities were studied. [Results] The fourth-grade seedlings had the least input, the highest yield of 6 948 kg/hm^2, the largest output-to-input ratio at 18.3, the highest root weight proportion of the second-grade product at 58.1%, and the lowest root weight proportion of the first-grade product at 17.6%. Considering the yield, quality and economic benefits comprehensively, the treatment of the fourth-grade seedlings(seedling diameter≤4 mm) is the best choice, and the suitable plant spacing is 8 cm×22 cm. [Conclusions] The study provided a reference basis for the cost saving and efficiency improvement of C. pilosula production.

Discovery of a potent and highly selective inhibitor of SIRT6 against pancreatic cancer metastasis in vivo

Pancreatic cancer,one of the most aggressive malignancies,has no effective treatment due to the lack of targets and drugs related to tumour metastasis.SIRT6 can promote the migration of pancreatic cancer and could be a potential target for antimetastasis of pancreatic cancer.However,highly selective and potency SIRT6 inhibitor that can be used in vivo is yet to be discovered.Here,we developed a noveSIRT6 allosteric inhibitor,compound 11e,with maximal inhibitory potency and an IC_(50) value of 0.98±0.13μmol/L.Moreover,compound 11e exhibited significant selectivity against other histone deacetylases(HADC1-11 and SIRT1-3)at concentrations up to 100μmol/L.The allosteric site and the molecular mechanism of inhibition were extensively elucidated by cocrystal complex structure and dynamic structural analyses.Importantly,we confirmed the antimetastatic function of such inhibitors in four pancreatic cancer cell lines as well as in two mouse models of pancreatic cancer liver metastasis.To our knowledge,this is the first study to reveal the in vivo effects of SIRT6 inhibitors on liver metastatic pancreatic cancer.It not only provides a promising lead compound for subsequent inhibitor developmentargeting SIRT6 but also provides a potential approach to address the challenge of metastasis in pancreatic cancer.

Detection and threshold-adaptive segmentation of farmland residual plastic film images based on CBAM-DBNet

Robust, accurate, and fast monitoring of residual plastic film (RPF) pollution in farmlands has great significance. Based on CBAM-DBNet, this study proposed a threshold-adaptive joint framework for identifying the RPF on farmland surfaces and estimating its coverage rate. UAV imaging was used to gather images of the RPF from several locations with various soil backgrounds. RPFs were manually labeled, and the degree of RPF pollution was defined based on the RPF coverage rate. Combining differentiable binarization network (DBNet) with the convolutional block attention module (CBAM), whose feature extraction module was improved. A dynamic adaptive binarization threshold formula was defined for segmenting the RPF’s approximate binary map. Regarding the RPF image detection branch, the CBAM-DBNet exhibited a precision (P) value of 85.81%, a recall (R) value of 82.69%, and an F1-score (F1) value of 84.22%, which was 1.09 percentage points higher than the DBNet in the comprehensive index F1 value. For the RPF image segmentation branch, using CBAM-DBNet to segment the RPF image combined with an adaptive binarization threshold formula. Subsequently, the mean absolute percentage error (MAPE), root mean square error (RMSE), and mean absolute error (MAE) of the prediction of RPF’s coverage rate were 0.276, 0.366, and 0.605, respectively, outperforming the DBNet and the Iterative Threshold method. This study provides a theoretical reference for the further development of evaluation technology for RPF pollution based on UAV imaging.

Alpha5 nicotine acetylcholine receptor subunit promotes intrahepatic cholangiocarcinoma metastasis

Neurotransmitter-initiated signaling pathway were reported to play an important role in regulating the malignant phenotype of tumor cells.Cancer cells could exhibit a"neural addiction"property and build up local nerve networks to achieve an enhanced neurotransmitter-initiated signaling through nerve growth factor-mediated axonogenesis.Targeting the dysregulated nervous systems might represent a novel strategy for cancer treatment.However,whether intrahepatic cholangiocarcinoma(ICC)could build its own nerve networks and the role of neurotransmitters in the progression ICC remains largely unknown.Immunofluorescence staining and Enzyme-linked immunosorbent assay suggested that IcC cells and the infiltrated nerves could generate a tumor microenvironment rich in acetylcholine that promotes IcC metastasis by inducing epithelial-mesenchymal transition(EMT).Acetylcholine promoted iCC metastasis through interacting with its receptor,alpha 5 nicotine acetylcholine receptor subunits(CHRNA5).Furthermore,acetylcholine/CHRNA5 axis activated GSK3β/β-catenin signaling pathway partially through the influx of Ca^(2+)-mediated activation of Ca/calmodulin-dependent protein kinases(CAMKll).In addition,acetylcholine signaling activation also expanded nerve infiltration through increasing the expression of Brain-Derived Neurotrophic Factor(BDNF),which formed a feedforward acetylcholine-BDNF axis to promote ICC progression.KN93,a small-molecule inhibitor of CAMKIll,significantly inhibited the migration and enhanced the sensitivity to gemcitabine of ICC cells.Above all,Acetylcholine/CHRNA5 axis increased the expression ofβ-catenin to promote the metastasis and resistance to gemcitabine of ICC via CAMKIl/GSK3βsignaling,and the CAMKIl inhibitor KN93 may be an effective therapeutic strategy for combating ICC metastasis.

Distribution characteristics of plastic film residue in long-term mulched farmland soil

Soil contamination from film debris following the prolonged application of mulching film has emerged as a worldwide concern.However,the extent that mulching films contribute to soil microplastics,and the spatial distribution of soil contamination from film debris remain unclear.In this study,the cotton field in Xinjiang(China),which underwent film mulching for a prolonged period of 5−30 years,was selected as the research location.A total of 360 soil samples were collected,aiming to study the spatial distribution characteristics of mulching film debris pollution.The samples were extracted using the density flotation method combined with stereomicroscopic;the source,composition,abundance,and distribution characteristics of soil MPs were identified by the scanning electron microscopic,and Fourier transform infrared spectroscopic analyses.In soil mulched for a 30 year period,the abundance of microplastics across the studied soil depth(0−60 cm)was 78.51±2.57 n/(100 g).Theμ-FTIR analyses revealed that the composition of the microplastics matched that of polyethylene materials.Therefore,plastic mulching could be inferred as a major contributor to microplastic pollution in agricultural lands.Overall,it is necessary to study the distribution characteristics of plastic film remaining for further study of plastic pollution in farmland soils.

Separation and mechanical properties of residual film and soil

In Xinjiang's perennial cotton(Gossypium hirsutum)-planting soil,the average residual amount of plastic film is as high as 265.3 kg/hm2,and the problem of pollution with residual plastic film in the tillage layer has become a major problem.To explore the mechanism of the separation of residual film and soil in the tillage layer and determine the conditions favorable for the separation of residual film-soil,this study established a constitutive model of residual film-soil contact based on the discrete element method and used the established constitutive model to simulate the process of separating residual film and soil.In addition,the influence of parameters,such as soil particle size and water content,on the force to separate the residual film and soil was studied using single factor and orthogonal experiments.The simulation results showed that the changing trend of the residual film-soil separation force curve did not differ much between the simulation and the actual comparison,and the curves were roughly the same.They all decreased after the separation force reached its peak value,but the simulated separation force curve was similar to that of the actual separation force.It increased rapidly from the beginning and reached peak separation force first.The single-factor experiment showed that the separation force of the used residual mulching film was higher than that of the unused mulching film.Under the same conditions,the maximum separation force required to separate the residual membrane was proportional to the positive pressure on the surface of the residual membrane and the size of soil particles.Under the same conditions,the maximum separation force required to separate the residual film is proportional to the positive pressure on the surface of the residual film and the size of soil particles.The maximum separation force decreased first and then increased as the soil moisture content increased.The results of the orthogonal experiment showed that the soil particle size had the greatest effect on the maximum separation force,followed by positive pressure on the residual film surface,soil moisture content,and the service life of mulch.In addition,film mulch that was buried 60 mm deep in the soil,a particle size of more than 2.5 mm,and a soil moisture content of 8%was the optimal combination of parameters to effectively separate the film mulching residue from the soil.

Impact of agricultural residual plastic film on the growth and yield of drip-irrigated cotton in arid region of Xinjiang, China

Long-term and widespread use of plastic mulching has led to the accumulation of residual plastic film(RPF)in farmland soils of Xinjiang,China.However,there is no specific quantitative basis for RPF pollution or a clear understanding of the influence of residual film on crop growth.The aim of this study was to investigate the effect of RPF on the growth of cotton,an important cash crop of Xinjiang.Based on the field conditions and previous reports,various amount of residual film was applied in 0-30 cm soil layer.The growth index including emergence rate,dry matter,and yield of cotton was examined at different growth stages under different soil residual film levels.Results demonstrated a significant effect of RPF on soil moisture distribution and movement.Plastic residues had a significant effect on cotton growth at levels above 200 kg/hm2,and the yield decreased as the RPF amount increased.Based on these findings,200 kg/hm2 was suggested as a threshold level to determine the effects of RPF on cotton.This study provided a basis to rate RPF pollution in farmland soils and help understand the impact of pollution on crop productivity.

Genome-wide Analysis of Transcriptional Variability in a Large Maize-Teosinte Population

Gene expression regulation plays an important role in controlling plant phenotypes and adaptation. Here, we report a comprehensive assessment of gene expression variation through the transcriptome analyses of a large maize-teosinte experimental population. Genome-wide mapping identified 25 660 expression quantitative trait loci （eQTL） for 17 311 genes, capturing an unprecedented range of expression variation. We found that local eQTL were more frequently mapped to adjacent genes, displaying a mode of expression piggybacking, which consequently created co-regulated gene clusters. Genes within the co-regulated gene clusters tend to have relevant functions and shared chromatin modifications. Distant eQTL formed 125 significant distant eQTL hotspots with their targets significantly enriched in specific functional cate- gories. By integrating different sources of information, we identified putative trans- regulators for a variety of metabolic pathways. We demonstrated that the bHLH transcription factor R1 and hexokinase HEX9 might act as crucial regulators for flavonoid biosynthesis and glycolysis, respectively. Moreover, we showed that domestication or improvement has significantly affected global gene expression, with many genes targeted by selection. Of particular interest, the Bx genes for benzoxazinoid biosynthesis may have undergone coordinated cis-regulatory divergence between maize and teosinte, and a transposon insertion that inactivates Bx12 was under strong selection as maize spread into temperate environments with a distinct herbivore community.

Construction of virtual mulch film model based on discrete element method and simulation of its physical mechanical properties

In China,especially in Xinjiang Region,mulch film remaining in the soil has severely jeopardized the safety of soil resources.To numerically simulate the residual film-soil-recovery implementation system,a virtual mulch film model with consistent physical and mechanical properties with real mulch film needs to be established.In this study,a flexible deformable virtual mulch film model was constructed using YADE software based on the Minkowski Sum principle and the ball-ball force-displacement constitutive rule,as well as the contact failure rule were established.The deformation behaviors of cylinders and PFacet elements,such as stretching,bending,and torsion,were described.By splicing the basic PFacet elements,a virtual mulch model was established.The mechanical model of a virtual mulch film under tension was established and the axial tensile stiffness coefficient kn was determined to be 43.30 N·m.To verify the physical and mechanical properties of this virtual mulch film,both real and virtual stretching and tearing tests were conducted.The experimental results showed that:in the process of stretching and tearing of real and virtual films,the properties of morphological features of both are basically identical;however,they clearly differ in force-displacement.The viscoelastic constitutive model between balls and yield judgment conditions requires further study.

Terrestrial carbon cycle model-data fusion:Progress and challenges

The terrestrial carbon cycle is an important component of global biogeochemical cycling and is closely related to human well-being and sustainable development.However,large uncertainties exist in carbon cycle simulations and observations.Model-data fusion is a powerful technique that combines models and observational data to minimize the uncertainties in terrestrial carbon cycle estimation.In this paper,we comprehensively overview the sources and characteristics of the uncertainties in terrestrial carbon cycle models and observations.We present the mathematical principles of two model-data fusion methods,i.e.,data assimilation and parameter estimation,both of which essentially achieve the optimal fusion of a model with observational data while considering the respective errors in the model and in the observations.Based upon reviewing the progress in carbon cycle models and observation techniques in recent years,we have highlighted the major challenges in terrestrial carbon cycle model-data fusion research,such as the“equifinality”of models,the identifiability of model parameters,the estimation of representativeness errors in surface fluxes and remote sensing observations,the potential role of the posterior probability distribution of parameters obtained from sensitivity analysis in determining the error covariance matrixes of the models,and opportunities that emerge by assimilating new remote sensing observations,such as solar-induced chlorophyll fluorescence.It is also noted that the synthesis of multisource observations into a coherent carbon data assimilation system is by no means an easy task,yet a breakthrough in this bottleneck is a prerequisite for the development of a new generation of global carbon data assimilation systems.This article also highlights the importance of carbon cycle data assimilation systems to generate reliable and physically consistent terrestrial carbon cycle reanalysis data products with high spatial resolution and longterm time series.These products are critical to the accurate estimation of carbon cycles at the global and regional scales and will help future carbon management strategies meet the goals of carbon neutrality.

Distribution of microplastics in mulched soil in Xinjiang, China

In order to study the distribution of soil microplastics in the plastic film mulched farmland,the fluidization-centrifugation secondary density flotation method was optimized and improved to obtain the samples.The main components of microplastics were analyzed by Fourier spectrometer,and the surface morphology,porosity,particle size and abundance distribution characteristics of microplastics were studied by electron microscopy.The results showed that plastic mulch is the main source of microplastics.Its morphology mainly consists of fragments,fibers and particles.The size of debris microplastics was larger,with an average of 1.6300 mm,mainly distributed in the 0-300 mm cultivation layer while the size of particle micro plastic was smaller,with an average of 0.1400 mm.The width of fiber microplastic was 5-20μm,but the length could reach 0.2000-2.0000 mm,with an average particle size of 0.9200 mm.Fiber and granular microplastics could be seen in each soil layer.The surface layer of microplastics has a large number of pores characterized with a length of 50μm and a width of about 5-10μm,which might be an easy oxidation site for microplastics.This oxidation is continuous,making microplastics continuously decompose into smaller particles.The abundance of microplastics is negatively correlated with soil depth.The average abundance of microplastics is 161.50±5.20 pieces/100 g in 0-300 mm soil layer,which is their main enrichment area.However,the average abundance of microplastics decreases to 11.20±1.10 pieces/100 g in 400-800 mm soil depth.Moreover,the average particle size of microplastics is also linearly negatively correlated with soil depth.Microplastics with smaller particle size are easier to migrate as they pass through soil pores under the action of water and fertilizer.The research can provide s reference for understanding plastic mulch pollution.

NAD^(+)-capped RNAs are widespread in rice(Oryza sativa)and spatiotemporally modulated during development

Dear Editor,Nicotinamide adenine dinucleotide(NAD+),a nucleotidecontaining metabolite,can be incorporated as an RNA 5′cap to form NAD^(+)-capped RNAs(NAD-RNAs),which have been identified in bacteria,yeast,mammalian cells and Arabidopsis thaliana(Hu et al.,2021).Most NAD-RNAs are m RNAs encoded by the nuclear and mitochondrial genomes。

Glossy15 Plays an Important Role in the Divergence of the Vegetative Transition between Maize and Its Progenitor, Teosinte

Dear Editor,The timing of developmental transitions is important for plant growth and environmental adaptation. All plants undergo a series of developmental transitions during their life cycles, and each of these phases is characterized by unique morphological and physiological attributes （Baurle and Dean, 2006）. In maize, the vegetative transition from juvenile-to-adult vegetative development occurs in a coordinated manner and is marked by the production of leaves that differ in a suite of morphological and physiological traits, many of which contribute to fitness and crop productivity （Moose and Sisco, 1994）. Significant advances have been made in understanding the molecular mechanisms regulating the juvenile-to-adult vegetative transition.