Effects of urbanization and forest type on species composition and diversity,forest characteristics,biomass carbon sink,and their associations in Changchun,Northeast China:implications for urban carbon stock improvement

Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban forests and improvement of function.To clarify the effect of two forest types with different urbanization intensities,we determined differences in vegetation composition and diversity,structural traits,and carbon stocks of 152 plots(20 m×20 m)in urban park forests in Changchun,which had the largest green quantity and carbon density effectiveness.We found that 1.1-fold thicker and healthier trees,and 1.6-to 2.0-fold higher,healthier,denser,and more various shrubs but with sparser trees and herbs occurred in the central urban forests(p<0.05)than in the outer forests.The conifer forests exhibited 30–70%obviously higher tree aboveground carbon sequestration(including stem and leaf)and 20%bigger trees,especially in the outer forests(p<0.05).In contrast,1.1-to 1.5-fold higher branch stocks,healthier and more diverse trees were found in broadleaved forests of both the inner and outer forests(p<0.05).Plant size and dominant species had similarly important roles in carbon stock improvement,especially big-sized woody plants and Pinus tabuliformis.In addition,a higher number of deciduous or needle species positively affected the broadleaved forest of the central urban area and conifer forest of the outer urban area,respectively.These findings can be used to guide precise management and accelerate the improvement of urban carbon function in Northeast China in the future.

Diverse responses of fungal functional groups to desertification in forest soils of Pinus densata on the Chinese Tibetan plateau

Rapid increase in desertification is an environ-mental concern,especially for the health and sustainabil-ity of ecosystems in changing climates.How ecosystems respond to such changes may be partially understood by studying interactions and performance of critically impor-tant groups such as soil fungi functional groups.This study investigated variations in diversities of three soil fungi functional guilds(saprotrophic,symbiotic,pathogenic)and influencing abiotic factors in a Pinus densata forest on the southeast Tibetan Plateau where desertification is intense.The results indicate desertification significantly decreased the proportion of dominant fungal guild-symbiotic fungi(mean relative abundance decreasing from 97.0%to 68.3%),in contrast to saprotrophic fungi(increasing from 2.7%to 25.7%)and pathogenic(from 0.3%to 5.9%).Soil pH had the most significant impact on fungal community structure and negatively correlated with symbiotic fungal richness,which was significantly lower in arid soils,and positively correlated with saprotrophic and pathogenic fungal alpha-diversity,which were abundant.Different community struc-tures and regulators of the three fungi communities were observed,with pH,total phosphorus and ammonium(NH_(4)^(+))as the main determinants.This study links the biotic and abi-otic components during desertification and the interactions between them,and may be used as indicators of ecosystem health and for amendments to mitigate the effects of a chang-ing climate.

Rational Design of Cost-Effective Metal-Doped ZrO_(2)for Oxygen Evolution Reaction

The design of cost-effective electrocatalysts is an open challenging for oxygen evolution reaction(OER)due to the“stable-oractive”dilemma.Zirconium dioxide(ZrO_(2)),a versatile and low-cost material that can be stable under OER operating conditions,exhibits inherently poor OER activity from experimental observations.Herein,we doped a series of metal elements to regulate the ZrO_(2)catalytic activity in OER via spin-polarized density functional theory calculations with van der Waals interactions.Microkinetic modeling as a function of the OER activity descriptor(G_(O*)-G_(HO*))displays that 16 metal dopants enable to enhance OER activities over a thermodynamically stable ZrO_(2)surface,among which Fe and Rh(in the form of single-atom dopant)reach the volcano peak(i.e.the optimal activity of OER under the potential of interest),indicating excellent OER performance.Free energy diagram calculations,density of states,and ab initio molecular dynamics simulations further showed that Fe and Rh are the effective dopants for ZrO_(2),leading to low OER overpotential,high conductivity,and good stability.Considering cost-effectiveness,single-atom Fe doped ZrO_(2)emerged as the most promising catalyst for OER.This finding offers a valuable perspective and reference for experimental researchers to design cost-effective catalysts for the industrial-scale OER production.

Interfacial built-in electric field and crosslinking pathways enabling WS_(2)/Ti_(3)C_(2)T_(x) heterojunction with robust sodium storage at low temperature

Developing efficient energy storage for sodium-ion batteries(SIBs)by creating high-performance heterojunctions and understanding their interfacial interaction at the atomic/molecular level holds promise but is also challenging.Besides,sluggish reaction kinetics at low temperatures restrict the operation of SIBs in cold climates.Herein,cross-linking nanoarchitectonics of WS_(2)/Ti_(3)C_(2)T_(x) heterojunction,featuring built-in electric field(BIEF),have been developed,employing as a model to reveal the positive effect of heterojunction design and BIEF for modifying the reaction kinetics and electrochemical activity.Particularly,the theoretical analysis manifests the discrepancy in work functions leads to the electronic flow from the electron-rich Ti_(3)C_(2)T_(x) to layered WS_(2),spontaneously forming the BIEF and“ion reservoir”at the heterogeneous interface.Besides,the generation of cross-linking pathways further promotes the transportation of electrons/ions,which guarantees rapid diffusion kinetics and excellent structure coupling.Consequently,superior sodium storage performance is obtained for the WS_(2)/Ti_(3)C_(2)T_(x) heterojunction,with only 0.2%decay per cycle at 5.0 A g^(-1)(25℃)up to 1000 cycles and a high capacity of 293.5 mA h g^(-1)(0.1A g^(-1)after 100 cycles)even at-20℃.Importantly,the spontaneously formed BIEF,accompanied by“ion reservoir”,in heterojunction provides deep understandings of the correlation between structure fabricated and performance obtained.

ExosomalmicroRNA let-7c-5p enhances cell malignant characteristics by inhibiting TAGLN in oral cancer

Background:Oral cancer,a malignancy that is prevalent worldwide,is often diagnosed at an advanced stage.MicroRNAs(miRNAs)in circulating exosomes have emerged as promising cancer biomarkers.The role of miRNA let-7c-5p in oral cancer remains underexplored,and its potential involvement in tumorigenesis warrants comprehensive investigation.Methods:Serum samples from 30 patients with oral cancer and 20 healthy controls were used to isolate exosomes and quantify their RNA content.Isolation of the exosomes was confirmed through transmission electron microscopy.Quantitative PCR was used to assess the miRNA profiles.The effects of let-7c-5p and TAGLN overexpression on oral cancer cell viability,migration,and invasion were analyzed via CCK-8 and Transwell assays.Moreover,we conducted mRNA sequencing of exosomal RNA from exosomes overexpressing let-7c-5p to delineate the gene expression profile and identify potential let-7c-5p target genes.Results:let-7c-5p was upregulated in serumderived exosomes of patients with oral cancer.Overexpression of let-7c-5p in the TCA8113 and CAL-27 cell lines enhanced their proliferative,migratory,and invasive capacities,and overexpression of let-7c-5p cell-derived exosomes promoted oral cancer cell invasiveness.Exosomal mRNA sequencing revealed 2,551 differentially expressed genes between control cell-derived exosomes and overexpressed let-7c-5p cell-derived exosomes.We further identified TAGLN as a direct target of let-7c-5p,which has been implicated in modulating the oncogenic potential of oral cancer cells.Overexpression of TAGLN reverses the promoting role of let-7c-5p on oral cancer cells.Conclusion:Our findings highlight the role of exosomal let-7c-5p in enhancing oral cancer cell aggressiveness by downregulating TAGLN expression,highlighting its potential as a diagnostic and therapeutic strategy.

Design of ZnSe-CoSe heterostructure decorated in hollow N-doped carbon nanocage with generous adsorption and catalysis sites for the reversibly fast kinetics of polysulfide conversion

Although lithium-sulfur batteries(Li SBs)are regarded as one of the most promising candidates for the next-generation energy storage system,the actual industrial application is hindered by the sluggish solid–liquid phase conversion kinetics,severe shuttle effect,and low sulfur loadings.Herein,a zeolitic imidazolate framework(ZIF)derived heterogeneous ZnSe-CoSe nanoparticles encapsulated in hollow N-doped carbon nanocage(ZnSe-CoSe-HNC)was designed by etching with tannic acid as a multifunctional electrocatalyst to boost the polysulfide conversion kinetics in LiSBs.The hollow structure in ZIF ensures large inner voids for sulfur and buffering volume expansions.Abundant exposed ZnSe-CoSe heterogeneous interfaces serve as bifunctional adsorption-catalytic centers to accelerate the conversion kinetics and alleviate the shuttle effect.Together with the highly conductive framework,the ZnSe-CoSeHNC/S cathode exhibits a high initial reversible capacity of 1305.3 m A h g-1at 0.2 C,high-rate capability,and reliable cycling stability under high sulfur loading and lean electrolyte(maintaining at 745 m A h g-1after 200 cycles with a high sulfur loading of 6.4 mg cm-2and a low electrolyte/sulfur ratio of 6μL mg^(-1)).Theoretical calculations have demonstrated the heterostructures of ZnSe-CoSe offer higher binding energy to lithium polysulfides than that of ZnSe or CoSe,facilitating the electron transfer to lithium polysulfides.This work provides a novel heterostructure with superior catalytic ability and hollow conductive architecture,paving the way for the practical application of functional sulfur electrodes.

Interface Engineering of Fe_(7)S_(8)/FeS_(2) Heterostructure in situ Encapsulated into Nitrogen‑Doped Carbon Nanotubes for High Power Sodium‑Ion Batteries

Heterostructure engineering combined with carbonaceous materials shows great promise toward promoting sluggish kinetics,improving electronic conductivity,and mitigating the huge expansion of transition metal sulfide electrodes for high-performance sodium storage.Herein,the iron sulfide-based heterostructures in situ hybridized with nitrogen-doped carbon nanotubes(Fe_(7)S_(8)/FeS_(2)/NCNT)have been prepared through a successive pyrolysis and sulfidation approach.The Fe_(7)S_(8)/FeS_(2)/NCNT heterostructure delivered a high reversible capacity of 403.2 mAh g^(−1) up to 100 cycles at 1.0 A g^(−1) and superior rate capability(273.4 mAh g^(−1) at 20.0 A g^(−1))in ester-based electrolyte.Meanwhile,the electrodes also demonstrated long-term cycling stability(466.7 mAh g^(−1) after 1,000 cycles at 5.0 A g^(−1))and outstanding rate capability(536.5 mAh g^(−1) at 20.0 A g^(−1))in ether-based electrolyte.This outstanding performance could be mainly attributed to the fast sodium-ion diffusion kinetics,high capacitive contribution,and convenient interfacial dynamics in ether-based electrolyte.

Attenuation of ethylene signaling increases cotton resistance to a defoliating strain of Verticillium dahliae

The severity of Verticillium wilt on cotton caused by defoliating strains of Verticillium dahliae has gradually increased and threatens production worldwide. Identification of the molecular components of leaf defoliation may increase cotton tolerance to V. dahliae. Ethylene, a major player in plant physiological processes, is often associated with senescence and defoliation of plants. We investigated the cotton–V.dahliae interaction with a focus on the role of ethylene in defoliation and defense against V. dahliae.Cotton plants inoculated with V. dahliae isolate V991, a defoliating strain, accumulated more ethylene and showed increased disease symptoms than those inoculated with a non-defoliating strain. In cotton with a transiently silenced ethylene synthesis gene(GhACOs) and signaling gene(GhEINs) during cotton–V. dahliae interaction, ethylene produced was derived from cotton and more ethylene increased cotton susceptibility and defoliation rate. Overexpression of AtCTR1, a negative regulator in ethylene signaling, in cotton reduced sensitivity to ethylene and increased plant resistance to V. dahliae.Collectively, the results indicated precise regulation of ethylene synthesis or signaling pathways improve cotton resistant to Verticillium wilt.

贫困农村家庭养育质量与儿童早期发展

家庭养育质量会对儿童早期发展产生深刻影响,本研究利用ASQ、ASQ:SE和PAFAS量表了解我国贫困农村0～3岁儿童早期发展和家庭养育状况,并通过单因素分析和多变量回归分析探究家庭养育质量与儿童早期发展的相关关系,结果表明我国贫困农村0～3岁儿童早期发展和家庭养育质量不容乐观,1/4的样本儿童在沟通、精细运动、粗大运动、解决问题和个人社会能力中至少有一项发育迟缓,样本家庭在儿童养育过程中行为一致性较差,倾向于使用打骂等暴力行为。单因素分析和多变量回归分析结果显示贫困农村家庭养育质量得分越高,儿童在沟通、精细运动、粗大运动、解决问题、个人社会以及社交情绪能力方面发展越好,说明家庭养育质量与儿童早期发展之间存在显著相关。今后应逐步将农村儿童早期发展服务纳入公共服务范畴;加大宣传力度,倡导科学育儿理念与方法,并进行相关养育技能培训,改变农村家庭传统育儿方式,提高农村家庭养育质量;加大对农村儿童早期发展服务人才和农村儿童早期发展研究的支持与投入。

Advances in optical engineering for future telescopes

Significant optical engineering advances at the University of Arizona are being made for design, fabrication, and construction of next generation astronomical telescopes. This summary review paper focuses on the technological advances in three key areas. First is the optical fabrication technique used for constructing next-generation telescope mirrors. Advances in ground-based telescope control and instrumentation comprise the second area of development. This includes active alignment of the laser truss-based Large Binocular Telescope(LBT) prime focus camera, the new MOBIUS modular cross-dispersion spectroscopy unit used at the prime focal plane of the LBT, and topological pupil segment optimization. Lastly, future space telescope concepts and enabling technologies are discussed. Among these, the Nautilus space observatory requires challenging alignment of segmented multi-order diffractive elements. The OASIS terahertz space telescope presents unique challenges for characterizing the inflatable primary mirror, and the Hyperion space telescope pushes the limits of high spectral resolution, far-UV spectroscopy. The Coronagraphic Debris and Exoplanet Exploring Pioneer(CDEEP) is a Small Satellite(Small Sat) mission concept for high-contrast imaging of circumstellar disks and exoplanets using vector vortex coronagraph. These advances in optical engineering technologies will help mankind to probe, explore, and understand the scientific beauty of our universe.

植物PHD结构域蛋白的结构与功能特性

植物同源结构域(plant homeodomain,PHD)是锌指结构域家族的一类转录调控因子,其最主要的功能是可以识别各种组蛋白修饰密码,包括组蛋白甲基化和乙酰化等;此外PHD结构域还可以与DNA结合。含有PHD结构域的蛋白,或者本身具有组蛋白修饰酶活性,或者可以与各类组蛋白修饰酶相互作用,还有部分与DNA甲基化相关,具有E3泛素连接酶活性,或者还可以作为染色质重塑因子,以各种不同的作用方式,在植物的生长发育过程中发挥了重要的作用。本文主要综述了结合各种类型组蛋白(包括H3K4me3/0、H3K9me3、H3R2和H3K14ac)以及DNA的PHD结构域的结构特点及其结合特异性、PHD结构域在植物中的进化保守性以及植物中已经发现的含有PHD结构域蛋白的功能及作用机制,为进一步了解该类蛋白在植物生长发育过程中如何发挥作用提供了参考。

The genome of Medicago polymorpha provides insights into its edibility and nutritional value as a vegetable and forage legume

Medicago polymorpha is a nutritious and palatable forage and vegetable plant that also fixes nitrogen.Here,we reveal the chromosome-scale genome sequence of M.polymorpha using an integrated approach including Illumina,PacBio and Hi-C technologies.We combined PacBio full-length RNA-seq,metabolomic analysis,structural anatomy analysis and related physiological indexes to elucidate the important agronomic traits of M.polymorpha for forage and vegetable usage.The assembled M.polymorpha genome consisted of 457.53Mb with a long scaffold N50 of 57.72Mb,and 92.92%(441.83Mb)of the assembly was assigned to seven pseudochromosomes.Comparative genomic analysis revealed that expansion and contraction of the photosynthesis and lignin biosynthetic gene families,respectively,led to enhancement of nutritious compounds and reduced lignin biosynthesis in M.polymorpha.In addition,we found that several positively selected nitrogen metabolism-related genes were responsible for crude protein biosynthesis.Notably,the metabolomic results revealed that a large number of flavonoids,vitamins,alkaloids,and terpenoids were enriched in M.polymorpha.These results imply that the decreased lignin content but relatively high nutrient content of M.polymorpha enhance its edibility and nutritional value as a forage and vegetable.Our genomic data provide a genetic basis that will accelerate functional genomic and breeding research on M.polymorpha as well as other Medicago and legume plants.

Helicobacter pylori antibody responses in association with eradication outcome and recurrence： a population-based intervention trial with 7.3-year follow-up in China

Objective： To identify serum biomarkers that may predict the short or long term outcomes of anti-Helicobacter gylori （H. pylori） treatment, a follow-up study was performed based on an intervention trial in Linqu County, China. Methods： A total of 529 subjects were selected randomly from 1,803 participants to evaluate total anti-H, pylori immunoglobulin G （IgG） and 10 specific antibody levels before and after treatment at 1-, 2- and 7.3-year. The outcomes of anti-H, pylori treatment were also parallelly assessed by 13C-urea breath test at 45-d after treatment and 7.3-year at the end of follow-up. Results： We found the medians of anti-H, pylori IgG titers were consistently below cut-off value through 7.3 years in eradicated group, however, the medians declined in recurrence group to 1.2 at 1-year after treatment and slightly increased to 2.0 at 7.3-year. While the medians were significantly higher （〉3.0 at 2- and 7.3-year） among subjects who failed the eradication or received placebo. For specific antibody responses, baseline seropositivities of FliD and HpaA were reversely associated with eradication failure [for FIiD, odds ratio （OR）=0.44, 95% confidence interval （95% CI）： 0.27-0.73; for HpaA, OR=0.32, 95% Ch 0.I7-0.60]. The subjects with multiple positive specific antibodies at baseline were more likely to be successfully eradicated in a linear fashion （Ptrend=0.006）. Conclusions： Our study suggested that total anti-H, pylori IgG level may serve as a potential monitor of long- term impact on anti-H, pylori treatment, and priority for H. pylori treatment may be endowed to the subjects with multiple seropositive antibodies at baseline, especially for FliD and HapA.

Simultaneous quantification of 18 bioactive constituents in Ziziphus jujuba fruits by HPLC coupled with a chemometric method

The fruit of Ziziphus jujuba Mill., known as Hongzao(or Hong-Zao) in Chinese and cultivated in China for more than 4 000 years, has shown to have hepatoprotective property. In previous study, we have isolated and identified 27 known compounds from Z. jujuba fruits, which demonstrated anti-tumor activity. In this study, a high-performance liquid chromatography-diode-array detection-mass spectrometry(HPLC-DAD-MS) method was successfully applied to the simultaneous characterization and quantitation of 18 constituents in 28 Z. jujuba samples, comprised of 12 cultivars from different regions in China, by comparing their HPLC retention times, MS spectra, UV spectra, and NMR data with those of reference compounds. The quantitative method was validated with excellent linearity(R^(2 )> 0.999 1), preferable intra-and inter-day precisions(RSD < 2.78%), and good recoveries(94.96%–102.65%). The content variation of 18 compounds was analyzed by a chemometric method(hierarchical cluster analysis). In addition, these constituents showed protection against carbon tetrachloride(CCl_(4)) intoxicated Hep G2 cell lines by decreasing lactic dehydrogenase(LDH) levels. Results in this study illustrated that the content of all 18 compounds examined has significant difference and variation among cultivars and extracts. The proposed method can serve as a prerequisite for quality control of bioactive compounds in Z. jujuba products.

Identifying candidate genes and patterns of heat-stress response in rice using a genome-wide association study and transcriptome analyses

Because high temperatures impair rice production,it is desirable to elucidate the regulatory mechanisms involved in rice response to heat stress.The objectives of this study were to identify candidate genes and characterize their response patterns during rice adaptation to high temperatures at the seedling stage.Ten heat-associated quantitative-trait loci were identified in a genome-wide association study.Comparison of transcript abundances in heat-sensitive and heat-tolerant rice pools under heat stress revealed approximately 400 differentially expressed genes.The expression of genes from heatsensitive accessions changed more than those from heat-tolerant accessions under heat stress.Alternative splicing(AS)events responded to heat stress in rice.The types of AS variants significant different between the heat-sensitive and heat-tolerant accessions.Expression patterns differing between the heat-sensitive and heat-tolerant accessions were identified for genes known to be involved in heat stress.We identified eleven genes associated with rice heat stress response.These genes could be pyramided to breed heat-tolerant rice accessions.

Amino acid permease 6 regulates grain protein content in maize

Grain protein content(GPC)is an indicator of cereal nutritional quality.Identification of genes involved in the regulation of GPC provides targets for molecular breeding for crop protein quality.We characterized a maize gene encoding the putative amino acid transporter ZmAAP6,a gene expressed mainly in immature seeds,especially in the basal endosperm transfer layer.Total protein and zein contents were decreased in ZmAAP6 null mutants and increased in ZmAAP6 overexpression(OE)lines,consistent with their changed in the size of protein bodies.Metabolic and transcriptomic analysis supported the regulatory role of ZmAAP6 in amino acid transportation.These results suggest that ZmAAP6 functions as a positive regulator of GPC in maize,shedding new light on the genetic basis of GPC regulation.

基于振动信号的轴承寿命预测

介绍了2012年IEEE PHM挑战赛关于轴承剩余使用寿命预测问题的专业类获奖算法,包括通过包络分析提取轴承特征频率法、PCA故障检测法以及在已知和未知轴承故障情况下预测剩余寿命的两种策略。

Incorporation of Carvedilol into PAMAM-functionalized MWNTs as a sustained drug delivery system for enhanced dissolution and drug-loading capacity

The purpose of this study was to develop poly(amidoamine)(PAMAM)-functionalized multi-walled carbon nanotubes(MWNTs)loaded with a poorly water-soluble drug,intended to improve the drug-loading capacity,dissolution and design a sustained release system.MWNTs were modified with a carboxyl group by acid treatment and then complex with PAMAM.PAMAM-MWNTs were investigated as a scaffold for loading the model drug,Carvedilol(CAR),using three different methods(the fusion method,the incipient wetness impregnation method,and the solvent method).The effects of different pore size,specific surface area and physical state were systematically studied using FT-IR,TGA,SEM,DSC,nitrogen adsorption,XPS and XRD.All the samples made by PAMAM-MWNTs to load the drug had a marked effect on the drug-loading capacity as well as drug dissolution,especially theⅡ-30%.

Microphone Array Speech Separation Algorithm Based on TC-ResNet

Traditional separation methods have limited ability to handle the speech separation problem in high reverberant and low signal-to-noise ratio(SNR)environments,and thus achieve unsatisfactory results.In this study,a convolutional neural network with temporal convolution and residual network(TC-ResNet)is proposed to realize speech separation in a complex acoustic environment.A simplified steered-response power phase transform,denoted as GSRP-PHAT,is employed to reduce the computational cost.The extracted features are reshaped to a special tensor as the system inputs and implements temporal convolution,which not only enlarges the receptive field of the convolution layer but also significantly reduces the network computational cost.Residual blocks are used to combine multiresolution features and accelerate the training procedure.A modified ideal ratio mask is applied as the training target.Simulation results demonstrate that the proposed microphone array speech separation algorithm based on TC-ResNet achieves a better performance in terms of distortion ratio,source-to-interference ratio,and short-time objective intelligibility in low SNR and high reverberant environments,particularly in untrained situations.This indicates that the proposed method has generalization to untrained conditions.

Speech Enhancement via Residual Dense Generative Adversarial Network

Generative adversarial networks(GANs)are paid more attention to dealing with the end-to-end speech enhancement in recent years.Various GANbased enhancement methods are presented to improve the quality of reconstructed speech.However,the performance of these GAN-based methods is worse than those of masking-based methods.To tackle this problem,we propose speech enhancement method with a residual dense generative adversarial network(RDGAN)contributing to map the log-power spectrum(LPS)of degraded speech to the clean one.In detail,a residual dense block(RDB)architecture is designed to better estimate the LPS of clean speech,which can extract rich local features of LPS through densely connected convolution layers.Meanwhile,sequential RDB connections are incorporated on various scales of LPS.It significantly increases the feature learning flexibility and robustness in the time-frequency domain.Simulations show that the proposed method achieves attractive speech enhancement performance in various acoustic environments.Specifically,in the untrained acoustic test with limited priors,e.g.,unmatched signal-to-noise ratio(SNR)and unmatched noise category,RDGAN can still outperform the existing GAN-based methods and masking-based method in the measures of PESQ and other evaluation indexes.It indicates that our method is more generalized in untrained conditions.