Why'the uplift of the Tibetan Plateau'is a myth

The often-used phrase'the uplift of the Tibetan Plateau'implies a flat-surfaced Tibet rose as a coherent entity,and that uplift was driven entirely by the colli...     

Integrated ‘all-in-one’ strategy to stabilize zinc anodes for high-performance zinc-ion batteries

Many optimization strategies have been employed to stabilize zinc anodes of zinc-ion batteries (ZIBs). Although these commonly used strategies can improve anode performance, they simultaneously induce specific issues. In this study, through the combination of structural design, interface modification, and electrolyte optimization, an ‘all-in-one’ (AIO) electrode was developed. Compared to the three-dimensional (3D) anode in routine liquid electrolytes, the new AIO electrode can greatly suppress gas evolution and the occurrence of side reactions induced by active water molecules, while retaining the merits of a 3D anode. Moreover, the integrated AIO strategy achieves a sufficient electrode/electrolyte interface contact area, so that the electrode can promote electron/ion transfer, and ensure a fast and complete redox reaction. As a result, it achieves excellent shelving-restoring ability (60 hours, four times) and 1200 cycles of long-term stability without apparent polarization. When paired with two common cathode materials used in ZIBs (α-MnO₂ and NH₄V₄O₁₀), full batteries with the AIO electrode demonstrate high capacity and good stability. The strategy of the ‘all-in-one’ architectural design is enlightened to solve the issues of zinc anodes in advanced Zn-based batteries.     

Phylogenetic patterns suggest frequent multiple origins of secondary metabolites across the seed-plant ‘tree of life’

To evaluate the phylogenetic patterns of the distribution and evolution of plant secondary metabolites (PSMs), we selected 8 classes of PSMs and mapped them onto an updated phylogenetic tree including 437 families of seed plants. A significant phylogenetic signal was detected in 17 of the 18 tested seed-plant clades for at least 1 of the 8 PSM classes using the D statistic. The phylogenetic signal, nevertheless, indicated weak clustering of PSMs compared to a random distribution across all seed plants. The observed signal suggests strong diversifying selection during seed-plant evolution and/or relatively weak evolutionary constraints on the evolution of PSMs. In the survey of the current phylogenetic distributions of PSMs, we found that multiple origins of PSM biosynthesis due to external selective forces for diverse genetic pathways may have played important roles. In contrast, a single origin of PSMs seems rather uncommon. The distribution patterns for PSMs observed in this study may also be useful in the search for natural compounds for medicinal purposes.     

从西藏地方立法角度探讨西藏生物遗传资源保护

以西藏生物遗传资源的丰富度及其特点为例,分析我国及其西藏地方立法的缺陷,提出针对遗传资源进行专门立法,进而对一些制度的建构进行讨论。     

探究西藏现代画家安多强巴的创作特色与理念

上个世纪藏族现代画家安多强巴倡导并实践了多元化的绘画风格,他在绘画题材的选择上不拘一格,除了传统的佛教题材之外,同时也致力于日常生活题材的艺术表现。一方面,安多强巴将佛教题材平易化,以多样化的绘画表现手法阐释了藏族艺术的内涵。另一方面他也将世俗人间的题材陌生化,以一种带有浓厚个人色彩的、角度特殊的绘画作品观照自然及社会万象。安多强巴的绘画风格、绘画技法和艺术理念等对当代的藏族绘画依然影响深远。     

基于GIS的西藏地区森林火险风险区划

选取降水、最高气温、相对湿度、平均风速、积雪日数和雷暴日数等气象因子;高程、坡度和坡向等地理因子;植被类型和NDVI等植被因子及交通、人口、居住地等社会因子作为森林火险的4个风险因子,采用指标归一法、层次分析法和加权综合评价法对西藏地区森林火险进行了定量评价,按火险等级将全区分为低、较低、中、较高和高等5类风险区,分别占40.2%、38.5%、14.4%、5.1%和1.8%,风险等级呈东高西低、南高北低的地理分布。最后利用2001-2012年火情监测公报的96个火点资料,对风险区划进行了评价对比,不同火险等级区的林火发生概率比为:9.8:5.7:3.0:0.2:0,区划结果能够为西藏森林火险防御规划提供参考。     

Utilization of biological variation data in the interpretation of laboratory test results – survey about clinicians’ opinion and knowledge

IntroductionTo interpret test results correctly, understanding of the variations that affect test results is essential. The aim of this study is: 1) to evaluate the clinicians’ knowledge and opinion concerning biological variation (BV), and 2) to investigate if clinicians use BV in the interpretation of test results.Materials and methodsThis study uses a questionnaire comprising open-ended and close-ended questions. Questions were selected from the real-life numerical examples of interpretation of test results, the knowledge about main sources of variations in laboratories and the opinion of clinicians on BV. A total of 399 clinicians were interviewed, and the answers were evaluated using a scoring system ranked from A (clinician has the highest level of knowledge and the ability of using BV data) to D (clinician has no knowledge about variations in laboratory). The results were presented as number (N) and percentage (%).ResultsAltogether, 60.4% of clinicians have knowledge of pre-analytical and analytical variations; but only 3.5% of them have knowledge related to BV. The number of clinicians using BV data or reference change value (RCV) to interpret measurements results was zero, while 79.4% of clinicians accepted that the difference between two measurements results located within the reference interval may be significant.ConclusionsClinicians do not use BV data or tools derived from BV such as RCV to interpret test results. It is recommended that BV should be included in the medical school curriculum, and clinicians should be encouraged to use BV data for safe and valid interpretation of test results.     

传统剂型与现代剂型相结合是发展藏药的大趋势

本文主要叙述传统藏药在新形式下所面临的挑战与机遇，同时探讨了有关藏药剂型改革与市场需求的关系问题。     

风险预期、市民化感知及农户认知对易地扶贫搬迁农户宅基地退出的影响

资金和土地问题是“后搬迁”时期易地扶贫搬迁接续推进农户减贫面临的两个重要约束条件,而搬迁农户宅基地退出是解决这一问题的关键。本文基于改进的计划行为理论,构建风险预期、市民化感知及农户认知对农户宅基地退出影响路径的理论框架,利用陕西省8县（区）1250份搬迁农户数据,采用混合结构方程模型进行检验,并分析了安置模式、农户年龄和政策认知的调节作用。结果表明：①风险预期和市民化感知对退出行为产生显著的直接影响,影响系数分别为-0.371和0.379,两者亦通过农户认知和退出意向的传导机制间接影响退出行为。②整体而言,宅基地退出行为受到农户认知的“自发性”、市民化感知的“政策协同性”和风险预期的“约束性”三重机制的影响。③分组结果显示：城镇化安置模式中,风险预期和市民化感知对退出行为的影响都更高;高龄组农户风险预期对行为态度和退出行为的约束性更强,而市民化感知的协同促进作用更低;政策认知会提高农户市民化感知对其退出行为的拉力,而降低风险预期的阻力。要实现宅基地顺利退出,在激活农户参与“自发性”的同时,通过升级农户市民化来提高搬迁对于宅基地退出的“协同性”拉动,同时通过就业扶持、优化搬迁前后社会保障制度的衔接等降低风险预期对宅基地退出的“约束性”作用。应根据不同的安置模式、不同农户年龄采取更加差异化的政策,不断提高农户的政策认知水平,从而精准、高效地推动搬迁农户退出宅基地。     

中国试点碳市场有效性的决定因素

温室气体大量排放引起的全球变暖受到广泛关注,中国政府试图通过发展碳市场以缓解气候变化问题和实现经济的绿色可持续发展.碳市场的有效性不仅对于能否实现减排目标、有效降低减排成本有重要影响,而且对我国统一碳市场的建立具有重要参考价值.目前全国统一碳市场正处于政策设计、基础建设和模拟运行阶段,由于碳交易是人为创设的市场,配额分...     

土地要素市场化配置对农户化肥用量的影响

已有研究主要从要素禀赋相对稀缺性视角来考察农户化肥用量差异,但普遍忽视了稀缺要素市场化配置的潜在影响。本文在理论层面阐明了土地要素市场化配置影响农户化肥用量决策的内在机理;进一步地,基于湖北省2016—2019年水稻种植户的独立混合截面数据,运用KV-IV估计方法和拓展回归模型估计了土地要素市场化配置对农户化肥用量的影响效应及传导机制。研究表明：①土地要素市场化配置水平对农户化肥用量具有显著的负向影响;②土地要素市场化配置主要通过土地经营规模与农户经营能力的匹配度,即土地要素配置效率作用于农户化肥用量决策;③土地要素市场不完全使相关要素市场的发育具有重要的资源配置意义,农户通过从事非农活动和购买生产性服务实现要素匹配,显著增强了土地要素配置效率改善带来的化肥减量施用效应。本文的理论意义在于为解释农户要素投入偏向提供一种有普遍意义的理论视角,有助于测度与诊断农业生产化肥高量乃至过量施用现象的根源与机制,实践意义在于为推进化肥减量施用提供政策参考。     

干旱背景下农户生产要素投入行为研究——以华北平原为例

气候变化导致极端天气事件频发给农业生产带来巨大挑战,明确农户生产行为是否受此影响,是进一步研究气候变化适应措施的关键。以华北平原为例,基于问卷调查数据,运用计量经济学方法,分析微观农户生产要素投入行为,评估干旱及生计资本等因素是否影响农户生产要素投入及其影响在不同类别农户间是否存在差异。结果表明：干旱影响农户生产要素投入行为,优化要素投入结构是农户应对旱灾的主要措施之一。生计资本差异也对农户生产要素投入行为构成显著影响,尤其是自然资本和社会资本,自然资本和社会资本越丰厚,农户生产要素投入相对越少。此外,农户内在特质和外在自然经济条件也是影响农户生产要素投入行为的重要因素,包括农户家庭基本状况、种植结构和所在村的自然地理条件等。为提升农户应对干旱等极端天气事件的能力,相关政策制定应根据不同因素影响有所侧重。     

Anthropogenic emission is the main contributor to the rise of atmospheric methane during 1993–2017

Atmospheric methane (CH₄) concentrations have shown a puzzling resumption in growth since 2007 following a period of stabilization from 2000 to 2006. Multiple hypotheses have been proposed to explain the temporal variations in CH₄ growth, and attribute the rise of atmospheric CH₄ either to increases in emissions from fossil fuel activities, agriculture and natural wetlands, or to a decrease in the atmospheric chemical sink. Here, we use a comprehensive ensemble of CH₄ source estimates and isotopic δ¹³C-CH₄ source signature data to show that the resumption of CH₄ growth is most likely due to increased anthropogenic emissions. Our emission scenarios that have the fewest biases with respect to isotopic composition suggest that the agriculture, landfill and waste sectors were responsible for 53 ± 13% of the renewed growth over the period 2007–2017 compared to 2000–2006; industrial fossil fuel sources explained an additional 34 ± 24%, and wetland sources contributed the least at 13 ± 9%. The hypothesis that a large increase in emissions from natural wetlands drove the decrease in atmospheric δ¹³C-CH₄ values cannot be reconciled with current process-based wetland CH₄ models. This finding suggests the need for increased wetland measurements to better understand the contemporary and future role of wetlands in the rise of atmospheric methane and climate feedback. Our findings highlight the predominant role of anthropogenic activities in driving the growth of atmospheric CH₄ concentrations.     

Why the whole is less than the sum of its parts: Examining knowledge management in acquisitions

This paper seeks to explain why an acquiring organization was unable to leverage the expertise of the acquired organization even though both organizations were highly successful in their own right prior to the acquisition. It offers a knowledge-based perspective by teasing out the essential knowledge attributes pertinent to acquisitions. The research was carried out using an interpretative case study methodology at a Singapore-based multinational organization in the semi-conductor industry. The main data collection method used was face-to-face interviews with some 28 staff from October 2006 to December 2006, almost 2 years after the acquisition exercise. The findings suggest that the lackluster outcome could be traced to three knowledge attributes, namely, accessibility, applicability and cumulativeness. In conclusion, a number of practical and research implications are highlighted.     

黑色旅游者行为意向差异研究——以侵华日军南京大屠杀遇难同胞纪念馆为例

黑色旅游地承载着苦难的记忆,不同旅游者可能表现出截然不同的心理和行为。本文通过调查南京大屠杀遇难同胞纪念馆的参观者,试图以重游意愿和推荐意愿为变量对黑色旅游者进行细分,以有针对性地强化黑色旅游在记忆传承和增强国家认同方面的作用。聚类分析得到行为意愿迥异的三类黑色旅游者：态度忠诚型、低重游低推荐型、态度和行为忠诚型。为进一步识别三类黑色旅游者在旅游限制和动机上的差异,结合网络文本分析构建了黑色旅游限制和动机量表,因子分析提取出7个限制因子：“伤痛记忆”、“恐惧和压抑”、“禁忌和文化观”、“缺乏兴趣”、“人际限制”、“时间/距离/信息”和“竞争旅游地”;3个动机因子：“责任与教育”、“社会因素”和“好奇和思考生死”。方差分析显示：旅游动机越强,旅游限制越弱,参观者选择重游和推荐意愿越强,反之亦然。研究发现为黑色旅游目的地管理提供了参考。     

中断模拟下的中国沿海集装箱港口航运网络脆弱性

双循环背景下,国内消费市场的持续扩大有望进一步增加港口内贸集装箱比例,而海洋集装箱运输极易受到外界因素的影响,因此对国内海洋集装箱运输网络脆弱性的研究必要而紧迫.本文在港口中断模拟下,运用复杂网络特征指标从网络结构和节点抗干扰性能两方面,分析2005年和2017年中国沿海集装箱港口航运网络脆弱性,并探讨脆弱性的主要影响...     

青藏高原民间舞蹈大众艺术体育初探——以锅庄舞为例

作为西部民族文化资源,藏族锅庄舞与现代社会大众多元化体育的对接、碰撞所产生的效果备受关注。通过对锅庄舞的种类及动作特点的分析,我们认为它属于民族传统体育范畴,从中发现无论是藏民还是汉民对于锅庄舞所具有一定艺术的审美情趣的价值是一致的。锅庄舞以多民族健身形式反映民众心理需求。