mlsa-iai-msu-lab/ru_sci_bench_zho_cite_reranking huggingface dataset:
Charcoal production through selective logging leads to degradation of dry woodlands: a case study from Mutomo District, Kenya

Provision of woodfuel is an important ecosystem service of dry forests and woodlands. However, charcoal production through selective logging of preferred hardwood species has the potential to alter the physiognomic composition of the residual or re-growth woodlands and may lead to their deterioration and degradation. This study, conducted through forest inventory in Mutomo District in Kenya, assessed the impact of charcoal production on unprotected dry woodlands in terms of tree density, targeted species basal area, species richness, evenness and Shannon diversity. The parameters of the disturbed woodlands were evaluated for significant differences with those of the neighbouring protected Tsavo East National Park, which served as a reference for an ecologically undisturbed ecosystem. By evaluating a consequence of tree harvesting for charcoal production, this study confirmed the overall significant differences between the protected and unprotected woodlands in all the tested parameters. To confirm if the differences in the land-covers of the woodlands had any influence on their degradation, all mentioned parameters were compared between the four differentiated classes and their respective control plots in the protected areas. At the "land-cover level", the statistically significant difference in the basal area of tree species preferred for charcoal production between the protected and unprotected open trees confirms that the class with a high density of large mature trees is the prime target of charcoal producers. In addition, there seems to be a general trend of lower values of tree species richness, evenness and Shannon diversity for the unprotected woodlands subjected to charcoal production. On the other hand, the disturbed woodlands display the potential to recover through their comparably high saplings density. The findings make an important contribution to the discourse on the impact of charcoal production in dry woodlands, a topic that is highly controversial among researchers.
Impact of sand burial on maize (Zea mays L.) productivity and soil quality in Horqin sandy cropland, Inner Mongolia, China

Croplands are often suffering from sand burial in dry regions of northern China. For studying this phenomenon, we carried out a case study of field experiment including four sand burial levels, i.e. shallow (1-3 cm), moderate (8-12 cm) and deep (15-20 cm) sand burials, and no sand burial (control, CK), in a typical agro-pastoral transitional zone in Naiman Banner of eastern Inner Mongolia. The aim of this study was to assess the impacts of sand burial on maize (Zea mays L.) productivity and the soil quality along a gradient of burial depths. Results showed that there was a strong negative effect of sand burial on maize productivity and soil quality, which significantly declined (P<0.05) under moderate and deep sand burial treatments. In comparison with the CK, the maize yield and above-ground biomass reduced by 47.41% and 39.47%, respectively. The soil silt and clay, soil water, soil organic carbon and total nitrogen contents under deep sand burial decreased by 67.85%, 40.32%, 86.52% and 82.11%, respectively, while microbial biomass carbon, microbial abundance and enzyme activity decreased by 89.78%, 42.28%-79.66% and 69.51%-97.71%, respectively. There was no significant effect on crop productivity and soil quality with shallow sand burial treatment. The correlations analysis showed that there was significant positive correlations of both maize yield and above-ground biomass with soil silt and clay, soil organic carbon and total nitrogen contents, pH, electrical conductivity, soil water content, microbial abundance and biomass and all tested soil enzyme activities. Stepwise regression analysis indicated that soil water and total nitrogen contents, urease, cellobiohydrolase and peroxidase activities were key determining factors for maize productivity. This combination of factors explains reason of the decreased maize productivity with deep sand burial. We found that degradation of cropland as a result of sand burial changed soil physical-chemical properties and soil enzyme activities in the plow layer, and decreased overall maize productivity. Furthermore, decreased soil enzyme activity was a better indicator to predict sandy cropland degradation.
Drought fluctuations based on dendrochronology since 1786 for the Lenglongling Mountains at the northwestern fringe of the East Asian summer monsoon region

The Lenglongling Mountains (LLM) located in northeastern part of the Tibet Plateau, belong to a marginal area of the East Asian summer monsoon (EASM) and are sensitive to monsoon dynamics. Two tree-ring width chronologies developed from six sites of Picea crassifolia in the LLM were employed to study the regional drought variability. Correlation and temporal correlation analyses showed that relationships between the two chronologies and self-calibrated Palmer Drought Severity Index (sc_PDSI) were significant and stable across time, demonstrating the strength of sc_PDSI in modeling drought conditions in this region. Based on the relationships, the mean sc_PDSI was reconstructed for the period from 1786 to 2013. Dry conditions prevailed during 1817-1819, 1829-1831, 1928-1931 and 1999-2001. Relatively wet periods were identified for 1792-1795 and 1954-1956. Spatial correlations with other fourteen precipitation/drought reconstructed series in previous studies revealed that in arid regions of Northwest China, long-term variability of moisture conditions was synchronous before the 1950s at a decadal scale (1791-1954). In northwestern margin of the EASM, most of all selected reconstructions had better consistency in low-frequency variation, especially during dry periods, indicating similar regional moisture variations and analogous modes of climate forcing on tree growth in the region.
降压目标值:指南推荐重要,还是个体化重要?

高血压是一种"心血管综合征",是脑卒中及冠状动脉性心脏病(冠心病)发病及死亡的最主要危险因素,积极控制血压可降低心脑血管病的发生率和死亡率。指南推荐,一般人群的降压目标值<140/90 mm Hg(1 mm Hg=0.133 kPa),老年人群的降压目标值可<150/90 mm Hg,如能耐受,可进一步降至<140/90 mm Hg。笔者从事心血管内科工作20余年,总结经验认为:降压目标值,个体化较指南推荐更重要。
Spatial distribution of mountainous regions and classifications of economic development in China

China is a mountainous country with a great diversity of landform and geomorphology. This diversity underlines the need for regionalization and classification. This study defines the mountain terrains and regions with three criteria - elevation, relative height, and slope, and examines the extent of mountainous regions by using county as the basic administrative unit. According to the three parameters of economic base, resident income and development potential, we classified the economic development level in mountainous regions of China. The findings reveal that the extent of the mountainous region accounts for 74.9% of the Mainland China’s total area. The economic development of mountainous regions in China is classified into 4 main types and 23 subtypes.
The Photonic Band Gaps in the Two-Dimensional Plasma Photonic Crystals with Rhombus Lattice

In this paper, under two different electromagnetic modes, the photonic band gaps (PBGs) in the two-dimensional plasma photonic crystals (PPCs) are theoretically investigated based on the plane wave expansion method. The proposed PPCs are arranged in rhombus lattices, in which the homogeneous unmagnetized plasma rods are immersed in the isotropic dielectric background. The computed results showed that PBGs can be easily tuned by the angle of rhombus lattices, and a cuto?frequency and a flatbands region can be observed under the TM and TE polarized waves, respectively. The relationships between the relative bandwidths of first PBGs and the parameters of PPCs in two such cases also are discussed. The numerical simulations showed that the PBGs can be manipulated obviously by the parameters as mentioned above. The proposed results can be used to design the waveguide and filter based on the PPCs.
强直性脊柱炎继发骨质疏松研究进展

AS是一种原因不明的慢性进行性炎性疾病,以骶髂关节、脊柱骨突、脊柱旁软组织及外周关节受累为主,严重者出现脊柱畸形和关节强直。本病男性多见,男女发病比例约为5:1,发病年龄通常在13~30岁,高峰年龄为20~30岁,40岁以后及8岁以前发病者少见。骨质疏松最早由Fagge在1877年进行AS患者尸检时发现,最初被认为与附着端的疼痛、脊柱的僵硬导致活动受限等废用性因素有关,而近年的研究表明,AS患者在疾病早期即可出现骨质疏松或骨量减少,增加了AS患者脊柱畸形、骨折、神经系统损伤的危险性,影响本病的预后。目前越来越多的学者关注并研究AS继发骨质疏松,为临床诊断及改善AS预后提供帮助。
老年颈动脉狭窄患者行颈动脉支架术后血清炎症因子和凝血因子的变化

目的分析老年颈动脉狭窄患者行颈动脉支架术后血清炎症因子和凝血因子的变化情况。方法选择83例颈动脉狭窄患者作为研究对象,根据是否接受介入治疗将其分为支架组(27例)和造影组(56例)。测定各组患者术前、术后1 d、术后3 d和术后1 w血清凝血因子和炎症因子水平,比较两组患者术前和术后不同时间血清凝血酶原时间(PT)、活化部分凝血酶原时间(APTT)、纤维蛋白原(FIB)、D-二聚体、纤维蛋白原降解产物(FDP)水平以及C-反应蛋白(CRP)、肿瘤坏死因子(TNF)-α、白细胞介素(IL)-6水平变化情况。结果支架组和造影组患者手术后血清各凝血因子较手术前均有不同程度的变化(P<0.05);支架组和造影组比较:支架组和造影组术前PT、APTT、FIB、D-二聚体和FDP水平比较均无统计学意义(P>0.05);支架组术后1 d和术后3 d PT、D-二聚体和FDP水平均高于造影组(P<0.05);支架组术后3 d APTT和FIB水平均高于造影组(P<0.05);术后1 w时支架组和造影组各凝血指标均基本恢复术前水平,两组之间比较无显著差异(P>0.05);支架组和造影组患者手术后血清各炎症因子较手术前均有不同程度的变化(P<0.05),支架组术后炎症反应较造影组明显(P<0.05)。结论老年颈动脉狭窄颈动脉支架术影响患者术后的血清炎症因子和凝血因子,该变化持续到术后1 w,之后逐渐恢复正常。
CTNNB1基因在卵巢癌组织中的表达及其相关性

目的分析CTNNB1在卵巢癌组织中的表达,探讨其与临床特征的关系。方法免疫组织化学方法检测CTNNB1在正常卵巢上皮组织及卵巢癌组织中的表达,分析其与临床特征间的关系;实时聚合酶链反应(PCR)法检测CTNNB1 mRNA的表达;Western印迹法检测CTNNB1蛋白的表达。结果正常的卵巢上皮组织未发现CTNNB1存在。在卵巢上皮性肿瘤组织中,93.3%的卵巢癌组织(42/45)出现了CTNNB1胞质表达。免疫组织化学染色结果显示,CTNNB1主要定位于细胞质,表现为染色后胞质内可见棕褐色的粒状物;CTNNB1在淋巴结转移患者组织中的表达比无淋巴结转移患者增加明显,而不同年龄、病理分期、组织学分化程度间的表达差异不显著;CTNNB1 mRNA和蛋白在卵巢癌组织及卵巢癌细胞株中表现为高表达,与正常的卵巢上皮组织差异显著,其中在细胞株中CAOV3的表达最高。结论CTNNB1在卵巢癌组织及细胞株中均有高表达,且与卵巢癌淋巴结转移关系密切。
循环压力泵治疗下肢动脉粥样硬化闭塞实验兔的疗效

目的探讨循环压力泵改善下肢动脉粥样硬化闭塞症(ASO)的疗效。方法将具有ASO的24只实验兔,随机分为A组和B组,每组12只,A组用循环压力泵对右下肢进行泵血,B组为循环压力泵未对右下肢股动脉进行泵血。穿刺股动脉,收取所需血液行生化检查。在压力泵最大转速(150 r/min)的转速下,收取血液行生化检查。以转速50 r/min,启动压力泵,持续给实验兔泵血1 h,术后再次抽出所需血液行生化检查,测量右下肢远端股动脉平均容积流量与平均血流速度;测量右下肢远端皮温;测量实验兔右下肢末端氧饱和度。结果①体外泵血前后K+、血常规、血沉指标差异无统计学意义(P>0.05)。②A组体内泵血前后电解质、肝功能、肾功能各项指标差异无统计学意义(P>0.05);B组体内泵血前后电解质、肝功能、肾功能各项指标差异无统计学意义(P>0.05)。③A、B两组体内泵血后平均容积流量与平均血流速度、右下肢远端温度差异、右下肢远端温度差异有统计学意义(P<0.05)。结论①在最大转速时,循环压力泵对血液生化无影响;②在一定的转速的范围内,循环压力泵对ASO兔股动脉泵血,未造成缺血再灌注损伤;③循环压力泵是一种有效的改善ASO兔下肢动脉血液供应的方法。
CETP基因I405V多态性对海南汉族老年脑梗死的分子预警作用

目的研究CETP遗传多态性位点I405V与海南汉族脑梗死的关联性。方法选择317例海南汉族脑梗死患者为实验组,305例海南省汉族健康人群为对照组,利用Snapshot的方法检测CETP基因I405V位点多态性,分析基因型频率及等位基因在组间的分布情况。结果I405V的AA、AG、GG三种基因型分布频率在实验组中为23.66%、47.63%、27.71%,在对照组中为16.07%、48.20%、35.74%,组间差异显著(P<0.05)。等位基因A和G在实验组中的分布频率为40.30%和60.03%,  对照组中的检出率为47.48%和52.52%,组间差异显著(P<0.05)。 结论I405V与海南汉族脑梗死关联性密切,有望成为脑梗死的分子预警指标。
甘草次酸对哮喘大鼠肺泡灌洗液白细胞计数及血清相关炎症因子的影响

目的探讨甘草次酸对哮喘大鼠肺泡灌洗液(BALF)白细胞计数及血清相关炎症因子的影响。方法选择健康清洁级雄性SD大鼠30只,随机分为哮喘模型组、甘草次酸组及正常对照组各10只。通过向哮喘模型组、甘草次酸组大鼠腹腔注射鸡卵清蛋白(OVA)+氢氧化铝凝胶致敏,并采用OVA雾化吸入激发形成哮喘模型。每次激发前2 h给予甘草次酸组大鼠10 mg/100 mg甘草次酸灌胃,哮喘模型组与正常对照组给予0.9%生理盐水0.1 ml/100 mg灌胃。最后一次激发完成后24 h内采集血清,采用酶联免疫吸附(ELISA)法测定三组血清免疫球蛋白(Ig)E、白细胞介素(IL)-13、IL-18、肿瘤坏死因子(TNF)-α水平,收集三组BALF对细胞沉渣进行瑞氏染色,并按照白细胞种类进行计数。结果根据临床症状及病理检查结果判定哮喘模型组、甘草次酸组造模成功;甘草次酸组较哮喘模型组中性粒细胞表达相对上升,但较正常对照组明显上升,而淋巴细胞及嗜酸性粒细胞表达较哮喘模型组相对降低,但较正常对照组明显上升(均P<0.05);哮喘模型组血清IgE、IL-13、TNF-α表达水平最高,甘草次酸组居中,正常对照组最低(P<0.05),而正常对照组IL-18表达水平最高,其次是甘草次酸组,哮喘模型组最低(P<0.05)。结论甘草次酸通过选择性诱导成熟T淋巴细胞凋亡,减少嗜酸性粒细胞的产生,抑制IgE、IL-13、TNF-α炎症因子表达,有效减轻哮喘大鼠气道炎症的产生,发挥平喘功效。
急性百草枯中毒患者病情及预后评价指标的研究进展

百草枯(PQ)又名克芜踪、对草快,化学名称为1,1-二甲基-4,4-二氯二吡啶,是一种廉价、高效的有机杂环类触杀型除草剂,由于其除草效能高且在农作物中低残留而在世界范围内广泛使用。在我国目前该农药已成为继有机磷农药之后第二大易中毒农药品种,每年有许多患者因自服、接触、吸人或误服导致中毒,近年来随着PQ使用量的日益增加,临床上中毒患者也呈上升趋势。由于肺脏是PQ蓄积的靶器官,其中毒后特征性病理改变表现为肺损伤,早期多发生以肺损伤为主的多脏器功能衰竭,晚期则出现不可逆性肺纤维化,由于目前尚无特效治疗措施,患者病死率极高。虽然许多患者早期临床症状并不明显,但患者结局却非常不理想,因此临床上需要一些客观指标来评价患者的病情及预后。目前国内外对于急性PQ中毒患者的严重程度和预后评价尚缺乏统一的量化标准,各种评价指标对其评估价值文献报道不一。我们将对目前用于急性PQ中毒患者的严重程度和预后评价的常见指标及其临床意义进行综述,便于临床实践过程中根据实际情况选择相应的评价指标。
原发性浆细胞白血病伴肾脏浸润一例

讨论浆细胞白血病(PCL)是浆细胞恶性增殖疾病,分为原发性(PPCL)和继发性(SPCL)两大类,PPCL起病时外周血中就有一定数量的浆细胞(通常>0.2),患者发病年龄轻,40岁以下约占20% ~ 35%。临床起病急,骨痛明显并伴有发热、出血及组织器官浸润,白细胞数常增高,骨髓检查可见浆细胞恶性增殖,并可累及外周血。 SPCL多发生于多发性骨髓瘤(MM),少数可见于巨球蛋白血症、恶性淋巴瘤等。MM继发的SPCL为MM终末期的改变,多有MM的病程,其发生机制与体内的高肿瘤负荷有关。PCL患者免疫表达浆细胞相关抗原CD38。外周血中浆细胞持续增加是诊断PCL的主要依据之一,也是与MM鉴别的重要标志。本例患者年龄29岁,以瘀斑及贫血等主要临床症状起病,从发病年龄、临床表现及实验室检查均符合PPCL。目前PPCL尚无根治方法,其治疗目的主要是延长生存期和提高生活质量。MM的常规化疗方案治疗PPCL反应率为25% ~ 82%,总生存期为2 ~ 22个月。联合化疗可能效果更好,但治疗后患者病程没有明显改善。有文献报道沙利度胺单用或联合化疗治疗PPCL可获得完全缓解,另外1病例用三氧化二砷治疗PPCL复发,获得完全缓解。近年来临床更多应用造血干细胞移植(HSCT)和新药治疗方法提高治疗PPCL的反应率,改善预后。HSCT是目前PPCL患者取得缓解后进行巩固治疗的选择。患者取得疗效后采用HSCT进行巩固治疗能够维持更长的缓解时间。沙利度胺、雷利度胺和硼替佐米等新药开始治疗PPCL的反应较好,但疗效持续时间短。硼替佐米是首个应用于临床的26S蛋白酶体抑制剂,具有靶向抗肿瘤作用,治疗MM效果良好。D'Arena等回顾性分析29例采用含硼替佐米方案治疗的患者,有效率为79%,完全缓解率为38%,表明硼替佐米治疗PPCL的反应率高,不良反应少,同时91%的肾功能损害患者血肌酐水平恢复正常。PPCL常合并多种并发症,伴有多器官功能障碍,总体治疗效果和预后差,确诊后中位生存期仅7个月左右。因此临床医生应早期明确诊断,排除引起肾功能损伤或溶骨性改变的其他疾病,及时进行化疗是提高本病疗效的关键。
新形势下科学基金国际化战略的思路与保障措施

科学研究正在日益成为全球化的事业,科技国际合作是促进各国科技发展和加强国家间关系的有效途径。为加强科学研究国际合作,各国科学基金资助机构全面战略规划国际合作,资助本国科学家以各种形式组织或参与国际大科学计划,积极推动本国科技进步,突出国际科技合作的战略地位,强调通过国际合作培养人才并积极吸引外国优秀人才为己所用。科技和经济发达国家科学基金资助机构多在国外设立办公室,延伸其影响力,为本国科学家与所在国科学家开展合作交流搭建有效平台。
脑磁图语言功能区定位在相关脑肿瘤手术中的应用

语言功能区肿瘤手术应最大范围地切除肿瘤,并尽可能保留语言功能。近年来脑磁图逐渐用于语言功能区的术前功能定位,以避免其术中损伤。我院2006年6月至2012年4月采用脑磁图语言功能区定位,部分病例联合应用神经导航手术治疗语言功能区肿瘤患者30例并取得较好疗效,现报告如下。
美国国家环境健康风险追踪体系及其启示

全球范围内24%的疾病负担可归因于环境因素,而在我国,大气、水体、土壤、室内空气污染及重金属暴露等危害随社会经济的快速发展趋于复合化,造成严重的环境健康问题,因此理清环境因素与健康效应的关系进而控制和减缓健康问题成为了我国公共卫生领域的挑战。获取环境与健康综合数据,是研究和解决环境健康问题的重要前提。环境健康综合监测对环境因素、健康效应同时开展监测,从而系统地获取环境污染物水平、人群健康效应现状与其二者的关系,这不仅对推进环境健康科学研究有重要作用,同时也有利于环境健康管理宏观决策与具体政策的制定,因此在我国开展环境健康综合监测具有重要意义。
东海深井地球物理长期观测仪器设置与观测研究

东海深井地球物理长期观测是我国开展深井地震学观测研究的第一步,其目的是为了排除地面干扰,取得高信噪比、高分辨率和高精度的地球物理观测资料.美国圣安德列斯断层项目组开展的深井综合地球物理观测研究项目在4 000m深井的不同深度处设置了多种观测仪器(Chavarria et al,2003),进行震源过程及地震预报等研究(Schleicher et al,2009;Tembe et al,2009;Jeppson,Tobin,2015).日本已建成数十所深井地球物理观测站,观测资料用于地震预报研究(Fujimoto et al,2007;石井紘,2010)以及2011年东日本M9巨大地震高滑动区域的动力学特征(Ikali et al,2015)等研究.联邦德国大陆深钻项目的主孔深达9 101m,4 000m先导孔注水诱发地震实验表明,诱发地震仅发生在该区10km深处脆延性过渡带以上的地层内(涂毅敏,陈运泰,2002).Ma等(2012)在我国台湾地区车龙埔断层上1 300m深的钻孔内设置了7台深井地震仪进行长期观测,并进行地震预报研究.
The Expansion of a Wedge of Gas into Vacuum with Small Angle in Two-Dimensional Isothermal Flow

In this paper, the authors consider the expansion problem of a wedge of gas into vacuum for the two-dimensional Euler equations in isothermal flow. By the bootstrapping argument, they prove the global existence of the smooth solution through the direct method in the case 0 < θ ≤ θ = arctan 1/((2+5~(1/2))~(1/2)), where θ is the half angle of the wedge. Furthermore, they get the uniform C~(1,1) estimates of the solution to the expansion problem.
肝细胞程序性坏死的研究进展

程序性坏死作为一种新发现的受信号分子调控的细胞死亡方式,参与多种疾病的发生和发展过程。与通常认为的坏死、凋亡和自噬不同,程序性坏死具有特异的分子机制,且其信号通路中的相关分子正成为人们研究的热点。近期有研究表明,程序性坏死均参与急性或慢性肝损伤、肝纤维化等过程,并与肝脏炎性疾病的发生发展有着密切的关系。因此,本文就程序性坏死的分子机制及其与肝细胞死亡的关系进行综述,为预防多种形式的肝损伤和治疗肝脏疾病提供新的思路。
Path-polarization hyperentangled and cluster states of photons on a chip

Encoding many qubits in different degrees of freedom(DOFs) of single photons is one of the routes toward enlarging the Hilbert space spanned by a photonic quantum state. Hyperentangled photon states(that is, states showing entanglement in multiple DOFs) have demonstrated significant implications for both fundamental physics tests and quantum communication and computation. Increasing the number of qubits of photonic experiments requires miniaturization and integration of the basic elements, and functions to guarantee the setup stability, which motivates the development of technologies allowing the precise control of different photonic DOFs on a chip. We demonstrate the contextual use of path and polarization qubits propagating within an integrated quantum circuit. We tested the properties of four-qubit linear cluster states built on both DOFs, and we exploited them to perform the Grover's search algorithm according to the one-way quantum computation model. Our results pave the way toward the full integration on a chip of hybrid multi-qubit multiphoton states.
Linking nutrient strategies with plant size along a grazing gradient: Evidence from Leymus chinensis in a natural pasture

Studying the changes in nutrient use strategies induced by grazing can provide insight into the process of grassland degradation and is important for improving grassland quality and enhancing ecosystem function. Dominant species in meadow steppe can optimize their use of limiting resources; however, the regulation of nutrient use strategies across grazing gradients is not fully understood. Therefore, in this study, we report an in situ study in which the impact of grazing rates on nutrient use strategies of Leymus chinensis, the dominant plant species in eastern Eurasian temperate steppes, was investigated. We conducted a large randomized controlled experiment (conducted continuously for five years in grassland plots in a natural pasture in Hailar, eastern Mongolia Plateau, China) to assess the effects of grazing rate treatments (0.00, 0.23, 0.34, 0.46, 0.69, and 0.92 adult cattle unit (AU) ha~(-1)) on L. chinensis along a grazing gradient and employed a random sampling approach to compare the accumulation, allocation, and stoichiometry of C, N, and P in leaves and stems. Our findings demonstrated the follows: (i) The height of L. chinensis decreased with an increase in the grazing gradient, and the concentrations of C, N, and P significantly increased; (ii) the accumulation of C, N, and P per individual was negatively correlated with the concentration of aboveground tissues, suggesting that there was a tradeoff in L. chinensis between nutrient accumulation and concentration at the individual scale; (iii) the leaf-to-stem ratio of C, N, and P accumulation increased with grazing intensity, indicating a tradeoff in nutrient allocation and plant size at the individual plant level; and (iv) grazing rates were negatively correlated with the ratios of C:N and C:P in the stem; however, these ratios in leaves significantly increased with grazing intensity. Our findings suggest that L. chinensis in meadow steppe adapts to grazing disturbance through tradeoffs between plant size and nutrient use strategies. Moreover, our results imply that grazing produces a compensatory effect on nutrient use efficiency between the stems and leaves of L. chinensis.
Transgenic restorer rice line T1c-19 with stacked cry1C*/bar genes has low weediness potential without selection pressure

Stacked (insect and herbicide resistant) transgenic rice T1c-19 with cry1C*/bar genes, its receptor rice Minghui 63 (herein MH63) and a local two-line hybrid indica rice Fengliangyou Xiang 1 (used as a control) were compared for agronomic performance under field conditions without the relevant selection pressures. Agronomic traits (plant height, tiller number, and aboveground dry biomass), reproductive ability (pollen viability, panicle length, and filled grain number of main panicles, seed set, and grain yield), and weediness characteristics (seed shattering, seed overwintering ability, and volunteer seedling recruitment) were used to assess the potential weediness without selection pressure of stacked transgene rice T1c-19. In wet direct-seeded and transplanted rice fields, T1c-19 and its receptor MH63 performed similarly regarding vegetative growth and reproductive ability, but both of them were significantly inferior to the control. T1c-19 did not display weed characteristics; it had weak overwintering ability, low seed shattering and failed to establish volunteers. Exogenous insect and herbicide resistance genes did not confer competitive advantage to transgenic rice T1c-19 grown in the field without the relevant selection pressures.
The effects of fertilization on the trait-abundance relationships in a Tibetan alpine meadow community

Aims Comparisons of the trait-abundance relationships from various habitat types are critical for community ecology, which can offer us insights about the mechanisms underlying the local community assembly, such as the relative role of neutral vs. niche processes in shaping community structure. Here, we explored the responses of trait-abundance relationships to nitrogen(N), phosphorus(P) and potassium(K) fertilization in an alpine meadow. Methods Five fertilization treatments(an unfertilized control and additions of N, P, K and NPK respectively) were implemented using randomized block design in an alpine Tibetan meadow. Species relative abundance(SRA), plant above-ground biomass and species richness were measured in each plot. For 24 common species, we measured species functional traits: saturated height, specific leaf area(SLA) and leaf dry matter content(LDMC) in each treatment but seed size only in the unfertilized control. Standard major axis(SMA) regression and phylogenetically independent contrasts(PICs) analysis were used to analyse species trait-abundance relationships in response to different fertilization treatments. Important Findings Positive correlations between SRA and saturated height were raised following N, P and NPK fertilizations, which indicated an increase in light competition in these plots. In P fertilized plots, SRA was also positively correlated with LDMC because tall grasses with a nutrients conservation strategy often have a relative competitive advantage in capturing limited light and soil nutrients. In K fertilized plots, neither the trait-abundance relationships nor above-ground biomass or species richness significantly differed from that in the control, which suggests that K was not a limiting resource in our study site. These significant correlations between species traits and relative abundance in fertilized treatment suggest that trait-based selection plays an important role in determining species abundance within local communities in alpine meadows.
Evaluation of the carbon isotopic effects of NDIR and CRDS analyzers on atmospheric CO_2 measurements

Non-dispersive infrared (NDIR) and cavity ring-down spectroscopy (CRDS) CO_2 analyzers use ~(12)CO_2 isotopologue absorption lines and are insensitive to all or part of other CO_2-related isotopologues. This may produce biases in CO_2 mole fraction measurements of a sample if its carbon isotopic composition deviates from that of the standard gases being used. To evaluate and compare the effects of carbon isotopic composition on NDIR and CRDS CO_2 analyzers, we prepared three test sample air cylinders with varying carbon isotopic abundances and calibrated them against five standard cylinders with ambient carbon isotopic composition using CRDS and NDIR systems. We found that the CO_2 mole fractions of the sample cylinders measured by G1301 (CRDS) were in good agreement with those measured by LoFlo (NDIR). The CO_2 values measured by both instruments were higher than that of a CO_2 isotope measured by G2201i (CRDS) analyzer for a test cylinder with depleted carbon isotopic composition δ~(13)C =-36.828‰, whereas no obvious difference was found for other two test cylinders with δ~(13)C=-8.630‰ and δ~(13)C=-15.380‰, respectively. According to the theoretical and experimental results, we concluded that the total CO_2 mole fractions of samples with depleted isotopic compositions can be corrected on the basis of their ~(12)CO_2 values calibrated by standard gases using LoFlo and G1301 if the δ~(13)C and δ~(18)O values are known.
Reaction heat-driven CO_2 desorption during CO oxidation on Au(997) at low temperatures

Adsorption and reaction of CO and CO_2 were studied on oxygen-covered Au(997) surfaces by means of temperatureprogrammed desorption/reaction spectroscopy. Oxygen atoms (O(a)) on Au(997) enhances the CO_2 adsorption and stabilizes the adsorbed CO_2(a), and the stabilization effect also depends on the CO_2(a) coverage and involved Au sites. CO_2(a) desorption is the rate-limiting step for the CO+O(a) reaction to produce CO_2 on Au(997) at 105 K and exhibits complex behaviors, including the desorption of CO_2(a) upon CO exposures at 105 K and the desorption of O(a)-stabilized CO_2(a) at elevated temperatures. The desorption of CO_2(a) from the surface upon CO exposures at 105 K to produce gaseous CO_2 depends on the surface reaction extent and involves the reaction heat-driven CO_2(a) desorption channel. CO+O(a) reaction proceeds more easily with weakly-bound oxygen adatoms at the (111) terraces than strongly-bound oxygen adatoms at the (111) steps. These results reveal complex rate-limiting CO_2(a) desorption behaviors during CO+O(a) reaction on Au surfaces at low temperatures which provide novel information on the fundamental understanding of Au catalysis.