COL4A2 enhances thyroid cancer cell proliferation through the AKT pathway

Objectives:Thyroid cancer(THCA)is the most common malignant tumor in endocrine system and the incidence has been increasing worldwide.And the number of patients dying from THCA has also gradually risen because the incidence continues to increase,so the mechanisms related to effective targets is necessary to improve the survival.This study was to preliminarily investigate the effects of the COL4A2 gene on the regulation of thyroid cancer(THCA)cell proliferation and the associated pathways.Methods:Bioinformatics analysis revealed that COL4A2 was closely associated with cancer development.COL4A2 expression in THCA tissues was analyzed using immunohistochemistry,and survival information was determined via Kaplan-Meier curves.The expression of COL4A2 and AKT pathway-related genes were analyzed using qPCR and western blot analyses.Colony formation as well as CCK-8 assays exhibited the cell proliferation level and cell activity,respectively.Downstream of COL4A2 was identified by Gene set enrichment analysis(GSEA).The effects of the COL4A2 and AKT pathways on THCA tumor growth in vivo were determined using a mouse model.Results:Bioinformatics analysis exhibited that COL4A2 plays a significant role in cancer and that the AKT pathway is downstream of COL4A2.THCA patients with high COL4A2 expression had shorter recurrence-free survival.Upregulation of COL4A2 gene expression in 2 THCA cell lines promoted tumor cell growth and activity.The use of AKT pathway blockers also restrained the growth and activity of the 2 THCA cell lines.The use of AKT pathway blockers reduced tumor volume and mass and prolonged mouse survival.Conclusions:COL4A2 can promote the growth as well as development of THCA through the AKT pathway and COL4A2 could be used as a target for THCA.

基于粗粒化分子动力学的自支撑石墨烯镜面屈曲研究

在扫描隧道显微镜的观测中发现了自支撑石墨烯膜镜面屈曲这一独特现象,目前尚少有研究人员对其进行系统性的研究.对于这种面外变形行为,不论是在实验观测,还是在能量收集系统这种潜在的应用形式中,石墨烯的尺寸都需要达到微米级.先前的研究表明,传统分子动力学适用于纳米尺度石墨烯的计算与分析,由于其计算方法的限制,在处理微米级模型时容易出现计算效率低、耗时长等问题.为了研究微米级尺寸石墨烯膜镜面屈曲现象,本文使用粗粒化分子动力学方法,首先验证该方法的适用性,然后分别施加不同大小的机械载荷和温度载荷在扇形截面不同高跨比的石墨烯膜上以分析各因素带来的影响.计算结果表明机械载荷作用下各个高跨比石墨烯均可以发生镜面屈曲现象,且临界载荷随高跨比的增大而增大;温度载荷作用下,高跨比较小的石墨烯能够发生完全翻转现象,大高跨比情况下温度升高使中心高度下降,但完全翻转较难发生.研究分析各因素对于石墨烯镜面屈曲现象的影响,可以加深对这一特殊现象了解的同时,为能量收集系统的设计提供理论指导.

铜死亡在肿瘤中的研究进展

铜离子作为人体正常生长发育必需的微量元素,广泛参与机体各种生理过程。铜代谢异常导致细胞毒性应激而死亡。铜死亡(cuproptosis)是一种新近提出的调节性细胞死亡方式,与细胞凋亡、铁死亡及自噬等其他细胞死亡途径不同,cuproptosis与细胞内铜离子的累积和线粒体代谢相关。cuproptosis在肿瘤的发生、发展和治疗具有一定的作用。同时,铜离子载体对肿瘤细胞的毒性作用也越来越受到关注。本文对cuproptosis的发生机制及其在不同肿瘤中的最新进展进行综述,并介绍铜离子载体在肿瘤治疗方面的研究现状。

高脂饮食诱导肥胖小鼠白色脂肪组织中IL-33的表达及意义

目的:探讨细胞因子IL-33在高脂饮食诱导的肥胖小鼠体内不同类型白色脂肪组织的表达情况。方法:3T3-L1前脂肪细胞诱导分化10 d, ELISA检测细胞培养上清中IL-33的含量;Western blot和RT-PCR检测细胞中IL-33的表达。6~8周的C57BL/6雄性小鼠随机分为两组,高脂组给予60%高脂饲料饲养10周,对照组用普通饲料,10周后,检测小鼠血清葡萄糖和血脂;ELISA检测血清中IL-33的含量;Western blot和RT-PCR检测不同类型白色脂肪组织中IL-33的表达。结果:3T3-L1前脂肪细胞诱导分化为成熟脂肪细胞后,细胞培养上清中IL-33含量无显著变化,细胞中IL-33的蛋白含量上调,IL-33 mRNA下调。在小鼠实验中,与对照组相比,高脂组小鼠体重显著升高,脂肪组织增重;高脂小鼠的空腹血糖、血清总胆固醇、高密度脂蛋白和IL-33浓度均显著升高,但血清甘油三酯和低密度脂蛋白无显著变化;高脂小鼠皮下脂肪组织中IL-33的蛋白含量增高,内脏脂肪组织中IL-33的蛋白水平降低,但IL-33 mRNA的表达与其蛋白水平正好相反。结论:高脂饮食诱导的肥胖小鼠皮下和内脏脂肪组织中IL-33有不同的表达,且与基因水平呈负相关,提示IL-33在不同白色脂肪组织发挥着不同的调节作用。

高脂饮食对小鼠不同组织中成纤维细胞生长因子21及其受体表达的影响

目的探讨成纤维细胞生长因子21(FGF21)及其受体在高脂饮食诱导的肥胖小鼠体内不同组织中的表达。方法选取6~8周龄C57BL/6雄性小鼠10只,适应性饲养1周后随机分为正常饮食组和高脂饮食组,每组5只。正常饮食组小鼠给予普通饲料;高脂饮食组小鼠给予高脂饲料,自由摄食及饮水,连续饲养10周,建立高脂饮食肥胖模型小鼠。采用酶联免疫吸附试验检测2组小鼠血清FGF21水平,实时荧光定量聚合酶链反应检测2组小鼠附睾脂肪组织、肝脏和骨骼肌组织中FGF21、FGF21受体(FGFR)和辅助受体β-Klotho表达,苏木精-伊红染色观察附睾脂肪组织和肝脏组织病理变化。结果喂养10周后,高脂饮食组小鼠体质量约为正常饮食组小鼠体质量的1.3倍,且体质量增量显著高于正常饮食组(P<0.01),高脂饮食诱导的肥胖小鼠模型制备成功。小鼠附睾脂肪组织结构正常,形态规则,细胞轮廓清晰,细胞核呈蓝色贴于细胞膜周边;正常饮食组小鼠附睾脂肪组织中脂肪细胞大小正常;而高脂饮食组小鼠附睾脂肪组织中脂肪细胞体积明显增大。正常饮食组小鼠肝脏组织结构正常;高脂饮食组小鼠肝组织内部分区域脂肪空泡显著增多,肝脏细胞表现出脂肪变性且周围有炎症细胞浸润。与正常饮食组比较,高脂饮食组小鼠血清FGF21水平显著升高(P<0.05),附睾脂肪组织中FGF21 mRNA相对表达量显著降低(P<0.05),肝脏组织和骨骼肌组织中FGF21 mRNA相对表达量升高(P<0.05);高脂饮食组小鼠附睾脂肪组织、肝脏组织和骨骼肌组织中FGFR、β-Klotho mRNA相对表达量显著低于正常饮食组(P<0.05,P<0.01)。结论高脂饮食诱导的肥胖小鼠体内不同组织中FGF21及其受体FGFR和β-Klotho表达失调。

The recurrence and survival of oral squamous cell carcinoma: a report of 275 cases

Oral squamous cell carcinoma(OSCC) is a common malignant tumor of the head and neck, and recurrence is an important prognostic factor in patients with OSCC. We explored the factors associated with recurrence of OSCC and analyzed the survival of patients after recurrence. Clinicopathologic and follow-up data of 275 patients with OSCC treated by surgery in the Cancer Institute and Hospital of Tianjin Medical University between 2002 and 2006 were analyzed. Recurrence factors were analyzed with Chisquare or Fisher′s exact test and multivariate analysis. The prognosis of patients after recurrence was analyzed with the Kaplan-Meier method and log-rank test. The recurrence rate was 32.7%. The recurrence time ranged from 2 to 96 months, with a median of 14 months. Univariate analysis showed that T stage, degree of differentiation, pN stage, flap application, resection margin, and lymphovascular invasion were factors of recurrence (P<0.05). Multivariate analysis showed that T stage, degree of differentiation, and pN stage were independent factors of recurrence (P<0.001). The differences in gender, age, tumor site, region of lymph node metastasis, and perineural invasion between the recurrence and non-recurrence groups were not significant (P>0.05). Kaplan-Meier and log-rank tests showed that the 2- and 5-year survival rates were significantly lower in the recurrence group than in non-recurrence group(67.6% vs. 88.0%, 31.8% vs. 79.9%, P<0.001). Therefore, to improve prognosis, we recommend extended local excision, flap, radical neck dissection, and adjuvant chemoradiotherapy for patients more likely to undergo recurrence.

Impacts of soil fauna on nitrogen and phosphorus release during litter decomposition were differently controlled by plant species and ecosystem type

The dynamics of litter nitrogen (N) and phosphorus (P) release could be affected by soil fauna and environmental conditions. The objective of the present study was to investigate the effects of soil fauna on the dynamics of N and P during foliar litter decomposition in three types of ecosystems (i.e., montane forest, ecotone, and dry valley) along an elevation gradient. A field experiment using litterbags with two different mesh sizes (0.04 and 3 mm) was conducted from November 2013 to October 2014. Nitrogen and P release rates in decomposing foliar litter from fir (Abies faxoniana) and birch (Betula albosinensis) in montane forest, oak (Quercus baronii) and cypress (Cupressus chengiana) in ecotone, and cypress and clovershrub (Campylotropis macrocarpa) in dry valley were investigated in the upper reaches of the Yangtze River. Soil fauna strongly affected N and P release across different decomposition periods and ecosystem types. The average release rate of N mediated by soil fauna across the entire year was higher in the dry valley (15.6–37.3%) than in the montane forest (0.5–6.4%) and the ecotone (- 3.7–4.9%). The effects of soil fauna on P release rate were manifest in both the montane forest and the dry valley. Moreover, the impacts of soil fauna can vary substantially among different decomposition periods. Our results indicated that soil fauna can significantly affect N and P release during litter decomposition. The N release rate mediated by fauna was likely to be more sensitive to the effects of plant species (i.e., initial litter chemical traits), while the P release rate mediated by soil fauna might be subject to the effects of local-scale environmental factors (e.g., temperature) to a greater extent.

腋乳入路达芬奇机器人甲状腺手术的临床应用研究

目的:探讨腋乳入路达芬奇机器人手术治疗甲状腺乳头状癌的临床效果和优势。方法:回顾性分析2017年11月至2020年3月天津医科大学肿瘤医院行甲状腺手术的338例甲状腺乳头状癌患者的临床资料,其中153例患者接受机器人甲状腺手术(机器人组),185例患者接受传统开放甲状腺手术(开放组)。应用移动平均线法绘制机器人组的学习曲线,分为学习期和平台期,并比较平台期机器人组与开放组的手术效果、并发症发生率及术后切口美容效果的差异。结果:机器人组患者平均年龄(34.7±8.3)岁,开放组患者平均年龄(37.0±8.4)岁,差异具有统计学意义(P<0.05)。在完成16例机器人甲状腺手术后,机器人组的手术时间明显缩短并趋于平稳。平台期机器人组的手术时间、术后引流量多于开放组,差异具有统计学意义(P<0.05)。两组术中出血量、术后引流时间、术后住院时长、中央区淋巴结清扫的总数目和转移数目的差异均无统计学意义(P>0.05)。平台期机器人组术后C-反应蛋白水平显著高于开放组,差异具有统计学意义(P<0.05)。平台期机器人组术后第1天切口疼痛视觉模拟评分低于开放组(P<0.05)。两组术后喉返神经损伤、甲状旁腺功能减退的发生率相近(P>0.05)。在全甲状腺切除术后1个月,两组甲状腺球蛋白水平的差异无统计学意义(P>0.05)。机器人组术后切口美观度的数字评分系统分值高于开放组,差异具有统计学意义(P<0.001)。结论:腋乳入路达芬奇机器人甲状腺手术治疗甲状腺乳头状癌安全可行,手术效果与传统开放手术相当,术后美容效果突出。

Resorption Efficiency of Four Cations in Different Tree Species in a Subtropical Common Garden

High rainfall in subtropical regions can leach cation elements from ecosystems,which may limit plant growth.Plants often develop efficient resorption patterns to recycle elements,but there is relatively little available information on this topic.In February 2012,a common garden was established in a subtropical forest by planting dominant trees from the area.Green and senescent leaves were sampled from 11 tree species.The concentrations of potassium(K),calcium(Ca),sodium(Na)and magnesium(Mg)were determined,and the resorption efficiencies were calculated.The results showed significant K,Na and Mg resorption in most of the investigated tree species,while Ca mainly displayed accumulation.Evergreen coniferous and evergreen broad-leaved trees(such as Cunninghamia lanceolata,Pinus massoniana,Cinnamomum camphora,and Michelia macclurei)exhibited relatively higher resorption efficiencies of K(39.0%-87.5%)and Na(18.3%-50.2%)than deciduous broad-leaved trees.Higher Mg resorption efficiencies(>50%)were detected in Liriodendron chinense,C.lanceolata and P.massoniana than in other trees.Overall,evergreen coniferous and evergreen broad-leaved trees could show higher cation resorption than deciduous broad-leaved trees.K and Mg resorption efficiencies and Ca accumulation decrease with increasing nutrient concentrations in green leaves.Our results emphasize that nutrient resorption patterns largely depend on elements and plant functions,which provides new insights into the nutrient use strategies of subtropical plants and a reference for the selection of suitable tree species in this region.

Gap edge canopy buffering of throughfall deposition in a subalpine natural forest

Base cation loads are rarely considered in forest gap edge canopies,but they can play critical roles in capturing or buffering atmospheric deposition in forests with frequent gap disturbances,such as subalpine forests.We selected an expanded gap edge canopy and a closed canopy in a subalpine natural forest on the eastern Tibetan Plateau.The throughfall deposition and canopy exchange processes of common base cations(K^(+),Ca^(2+),Na^(+),and Mg^(2+))were continuously studied over two years.The results showed that the enrichment ratio and fluxes had lower levels of base cations in the gap-edge canopy than in the closed canopy,which indicated that base cations were concentrated more in the closed canopy than in the gap-edge canopy.Although Ca^(2+)in the gap-edge canopy showed a higher net throughfall flux,the annual net throughfall fluxes of K^(+),Na^(+) and Mg^(2+) within the gap-edge canopy were 1.83,6.75 and 2.95 times lower than those in the closed canopy,respectively.Moreover,dry deposition fluxes of base cations significantly decreased in the gap edge canopy compared to those in the closed canopy,and the decreasing tendency was more significant during the snowy season than during the rainy season.Overall,these results suggest that the amount of base cations in subalpine natural forest ecosystems may be overestimated when the throughfall deposition of ions in gap edge canopies is ignored.

Lattice Boltzmann Simulation of Nanoparticle Transport and Attachment in a Microchannel Heat Sink

The heat transfer performances of a microchannel heat sink in the presence of a nanofluid can be affected by the attachment of nanoparticle(NP)on the microchannel wall.In this study,the mechanisms underlying NP transport and attachment are comprehensively analyzed by means of a coupled double-distribution-function lattice Boltzmann model combined with lattice-gas automata.Using this approach,the temperature distribution and the two-phase flow pattern are obtained for different values of the influential parameters.The results indicate that the number of attached NPs decrease exponentially as their diameter and the fluid velocity grow.An increase in the wall temperature leads to an increase of the attached NPs,e.g.,the Al_(2)O_(3) NPs attached on the CuO microchannel wall increases by 105.8%in the range between 293 K and 343 K.There are more attached NPs in microchannels with an irregular structure.The tendency of SiO2 NP to attach to the PDMS(polydimethylsiloxane),Fe and Cu walls is less significant than that for Al_(2)O_(3) and CuO NP;Moreover,NPs detach from the PDMS microchannel wall more easily than from the Cu and Fe microchannel walls.The SiO2 attachment layer has the greatest influence on the heat transfer performance although its thickness is thinner than that for Al_(2)O_(3) and CuO NPs under the same conditions.

JPE Best Paper awards(2021)

In 2022,Journal of Plant Ecology(JPE)established the JPE Best Paper awards to recognize the papers published in JPE with high impacts in the field of plant ecology(Zhang and Schmid 2022).This award is given annually to the first author(s)of two to five papers selected by the editors based on the novelty and contributions to the field of plant ecology.

IL-33/ST2轴对脂肪组织免疫细胞的调控作用及其与肥胖的关系

肥胖是全社会普遍关注的健康问题。大量研究表明,肥胖可导致脂肪组织内免疫细胞亚群的种类和数量及免疫分子的改变,IL-33/ST2在维持其稳态方面发挥着至关重要的作用。本文就近年来IL-33/ST2对脂肪细胞及脂肪组织免疫细胞的调控作用以及肥胖条件下脂肪组织局部和全身IL-33的改变两个方面进行了综述。

全球尺度上氮添加影响植物生物量分配但不影响不同器官间的异速生长关系

生物量在不同器官间的分配是植物对环境变化响应的一个关键生态生理学过程。然而,在全球尺度上有关不同陆地生态系统植物生物量分配对氮沉降响应的认识还比较欠缺。本文通过整合分析333篇己发表文章的5474个观测值,基于“最优分配假说”和“异速分配假说”,评估了全球尺度上氮添加对植物生物量及其在不同器官间分配的影响。结果表明:(1)氮添加显著增加了整株植物或不同器官的生物量,降低了根冠比和根质量分数,但对叶质量分数和茎质量分数无显著影响;(2)氮添加对不同器官质量分数的影响受实验条件、植物功能性状、纬度、氮添加率等因子单独或交互作用的调控;(3)氮添加对生物量在不同器官间的异速分配率无显著影响,表明氮添加导致的根冠比和根质量分数减少是在异速分配模式下由整株植物生物量增加而致。虽然氮添加改变了地上和地下部分的质量分数,但不同器官生物量间异速分配模式的稳定性表明“异速分配假说”能更好地描述植物生物量分配对氮添加的响应规律。该研究结果将有助于深入认识氮沉降环境下植物生物量的分配规律,同时表明将生物量分配纳入有关氮沉降对陆地生态系统影响的预测模型中的重要性。

An Analytic Solution of One-dimensional Steady-state Pennes' Bioheat Transfer Equation in Cylindrical Coordinates

Based on the Pennes’ bioheat transfer equation, a simplified one-dimensional bioheat transfer model of the cylindrical living tissues in the steady state has been set up for application in limb and whole body heat transfer studies, and by using the Bessel’s equation, its corresponding analytic solution has been derived in this paper. With the obtained analytic solution, the effects of the thermal conductivity, the blood perfusion, the metabolic heat generation, and the coefficient of heat transfer on the temperature distribution in living tissues are analyzed. The results show that the derived analytic solution is useful to easily and accurately study the thermal behavior of the biological system, and can be extended to such applications as parameter measurement, temperature field reconstruction and clinical treatment.

白蚁活动对中亚热带次生林和人工林的危害差异

中亚热带地区是中国南方重要的木材生产基地,大量的地带性常绿阔叶林被转换成以杉木(Cunninghamia lanceolata)为代表的人工林。白蚁是森林中最主要的社会性昆虫之一,其取食行为既对森林类型转换后林中的树木产生危害,也对林间枯枝落叶的分解具有十分重要的意义,但对二者缺乏统一的认识。本文以中亚热带典型的米槠(Castanopsis carlesii)次生林、米槠人工林和杉木人工林为研究对象,调查了不同林分白蚁的活动特点及其范围。结果表明,米槠次生林与杉木、米槠人工林中均普遍存在白蚁取食现象,但白蚁对次生林的取食高度和面积均远低于人工林。白蚁对生物多样性较高的米槠次生林树干韧皮部的取食面积仅分别为米槠人工林的1.65%和杉木人工林的0.59‰,取食高度的11.1%和1.2%。同时,白蚁对杉木韧皮部的取食显著大于米槠,对杉木的取食面积和高度分别是米槠的27.7倍和9.2倍。每隔0.5 m为一个统计区间,白蚁对杉木树干2 m以下韧皮部取食面积比例由低往高为4:3:2:1,对米槠1 m以下高度部位的取食面积比为99:1。此外,白蚁对次生林地表覆盖的凋落枝和凋落叶的平均取食面积分别为51.7%和46.1%,而人工林对应均值分别为17.5%和29.4%,均表现为次生林高于人工林。这些结果表明白蚁对生物多样性较高的次生林危害小于杉木人工林,且在人工林中可见危害主要体现在白蚁对韧皮部的取食,在次生林主要体现在白蚁对凋落物残体的分解作用,这为区域森林经营管理提供理论支撑。

Increased microbial sequestration of soil organic carbon under nitrogen deposition over China’s terrestrial ecosystems

Background:China’s terrestrial ecosystems have been receiving increasing amounts of reactive nitrogen(N)over recent decades.External N inputs profoundly change microbially mediated soil carbon(C)dynamics,but how elevated N affects the soil organic C that is derived from microbial residues is not fully understood.Here,we evaluated the changes in soil microbial necromass C under N addition at 11 forest,grassland,and cropland sites over China’s terrestrial ecosystems through a meta-analysis based on available data from published articles.Results:Microbial necromass C accounted for an average of 49.5%of the total soil organic C across the studied sites,with higher values observed in croplands(53.0%)and lower values in forests(38.6%).Microbial necromass C was significantly increased by 9.5%after N addition,regardless of N forms,with greater stimulation observed for fungal(+11.2%)than bacterial(+4.5%)necromass C.This increase in microbial necromass C under elevated N was greater under longer experimental periods but showed little variation among different N application rates.The stimulation of soil microbial necromass C under elevated N was proportional to the change in soil organic C.Conclusions:The stimulation of microbial residues after biomass turnover is an important pathway for the observed increase in soil organic C under N deposition across China’s terrestrial ecosystems.

Changes in soil faunal density and microbial community under altered litter input in forests and grasslands

Root and foliar litter inputs are the primary sources of carbon and nutrients for soil fauna and microorganisms,yet we still lack a quantitative assessment to evaluate the effects of root and foliar litter on various groups of soil organisms across terrestrial ecosystems.Here,we compiled 978 paired observations from 68 experimental sites to assess the directions and magnitudes of adding and removing foliar and root litter on the soil faunal density and microbial biomass that was evaluated by phospholipid fatty acids(PLFAs)across forests and grasslands worldwide.We found that litter addition had only a marginal effect on soil faunal density but significantly increased the soil total microbial-,fungal-and bacterial-PLFAs by 13%,14%,and 10%,respectively,across ecosystems,suggesting that the soil microbial community is more sensitive to carbon source addition than soil fauna,particularly in soils with low carbon to nitrogen ratios.In contrast,removing litter significantly decreased the soil faunal density by 17%but had few effects on soil microorganisms.Compared with foliar litter,root litter input had a more positive effect on the development of soil fungal taxa.The effect of both litter addition and removal on soil faunal density and microbial biomass did not differ between humid and arid regions,but a greater influence was observed in grasslands than in forests for soil microbial community.Our results highlight that the increasing litter production under a global greening scenario would stimulate microbial activity in grasslands more than in forests,and this stimulation would be greater for soil microbes than soil fauna.

Warming and altered precipitation rarely alter N addition effects on soil greenhouse gas fluxes:a meta-analysis

Background Changes in soil greenhouse gas(GHG)fluxes caused by nitrogen(N)addition are considered as the key factors contributing to global climate change(global warming and altered precipitation regimes),which in turn alters the feedback between N addition and soil GHG fluxes.However,the effects of N addition on soil GHG emissions under climate change are highly variable and context-dependent,so that further syntheses are required.Here,a meta-analysis of the interactive effects of N addition and climate change(warming and altered precipitation)on the fluxes of three main soil GHGs[carbon dioxide(CO_(2)),methane(CH_(4)),and nitrous oxide(N_(2)O)]was conducted by synthesizing 2103 observations retrieved from 57 peer-reviewed articles on multiple terrestrial ecosystems globally.Results The interactive effects of N addition and climate change on GHG fluxes were generally additive.The combination of N addition and warming or altered precipitation increased N_(2)O emissions significantly while it had minimal effects on CO_(2)emissions and CH_(4)uptake,and the effects on CH_(4)emissions could not be evaluated.Moreover,the magnitude of the combined effects did not differ significantly from the effects of N addition alone.Apparently,the combined effects on CO_(2)and CH_(4)varied among ecosystem types due to differences in soil moisture,which was in contrast to the soil N_(2)O emission responses.The soil GHG flux responses to combined N addition and climate change also varied among different climatic conditions and experimental methods.Conclusion Overall,our findings indicate that the effects of N addition and climate change on soil GHG fluxes were relatively independent,i.e.combined effects of N addition and climate change were equal to or not significantly different from the sum of their respective individual effects.The effects of N addition on soil GHG fluxes influence the feedbacks between climate change and soil GHG fluxes.