Magnitude

量值
  • 文章类型: Meta-Analysis
    将生物炭施用于土壤已被认为是气候智能型农业的一种有前途的做法,在增强土壤有机碳(SOC)固存方面具有相当大的潜力。以前的研究表明,生物炭诱导的SOC存量增加在实验中变化很大,而造成这种变异性的解释因素仍未得到很好的评估。这里,我们对生物炭引起的SOC存量变化的幅度和效率进行了综合荟萃分析,使用一个数据库,包括全球101个站点的476个现场测量。生物炭修正使SOC存量增加6.13±1.62(95%置信区间,CI)和7.01±1.11(95%CI)MgCha-1,与未施肥(R0)和矿物氮(N)施肥(Rn)参考文献相比。其中大约。52%(R0)和50%(Rn)由生物炭-C输入直接贡献。R0和Rn数据集中相应的生物炭碳效率估计为58.20±10.37%和65.58±9.26%(95%CI),分别。SOC存量的变化幅度随着生物炭-C输入量的增加而显著增加(p<0.01),而生物炭的碳效率表现出相反的趋势。与碱性和沙质土壤相比,生物炭改良剂在酸性和肥沃土壤中以更高的效率隔离了更多的SOC。具有较高C/N比的生物炭改良剂比具有较低C/N比的生物炭引起较高的SOC增加。随机森林(RF)算法表明,累积的生物炭-C输入,土壤pH值,和生物炭碳氮比是调节SOC存量响应的三个最重要因素。总的来说,这些结果表明,从增强有机碳的角度来看,在酸性土壤中施用高C/N比生物炭是值得推荐的农业实践。
    Applying biochar to soil has been recognized as a promising practice of climate-smart agriculture, with considerable potential in enhancing soil organic carbon (SOC) sequestration. Previous studies showed that biochar-induced increases in SOC stock varied substantially among experiments, while the explanatory factors responsible for such variability are still not well assessed. Here, we conducted an integrative meta-analysis of the magnitude and efficiency of biochar-induced change in SOC stock, using a database including 476 field measurements at 101 sites across the globe. Biochar amendment increased SOC stock by 6.13 ± 1.62 (95% confidence interval, CI) and 7.01 ± 1.11 (95% CI) Mg C ha-1, respectively, compared to their unfertilized (R0) and mineral nitrogen (N) fertilized (Rn) references. Of which approx. 52% (R0) and 50% (Rn) were contributed directly by biochar-C input. Corresponding biochar carbon efficiencies in R0 and Rn datasets were estimated as 58.20 ± 10.37% and 65.58 ± 9.26% (95% CI), respectively. The change magnitude of SOC stock increased significantly (p < 0.01) with the increasing amount of biochar-C input, while carbon efficiency of biochar showed an opposite trend. Biochar amendment sequestered larger amounts of SOC with higher efficiency in acidic and loamy soils than in alkaline and sandy soils. Biochar amendments with higher C/N ratio caused higher SOC increase than those with lower C/N ratio. Random forest (RF) algorithm showed that accumulative biochar-C input, soil pH, and biochar C/N ratio were the three most-important factors regulating the SOC stock responses. Overall, these results suggest that applying high C/N ratio biochar in acidic soils is a recommendable agricultural practice from the perspective of enhancing organic carbon.
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  • 文章类型: Journal Article
    通过秸秆还田(SR)提高土壤有机碳(SOC)已被广泛推荐为气候智能型农业的一种有希望的做法。许多研究已经调查了秸秆还田对SOC含量的相对影响,而秸秆还田在积累SOC存量方面的规模和效率仍不确定。这里,我们提出了SR引起的SOC变化的幅度和效率的综合,使用一个数据库,包括全球115个地点的327个观察结果。秸秆还田使SOC增加3.68±0.69(95%置信区间,CI)MgCha-1,相应的C效率为20.51±9.58%(95%CI),其中<30%是由秸秆C输入直接贡献的。SR引起的SOC变化幅度随着秸秆C输入和实验持续时间的增加而增加(P<0.05)。然而,在这两个解释因素下,C效率显着降低(P<0.01)。发现免耕和轮作可以增强SR引起的SOC增加,无论是规模还是效率。与碱性和有机贫瘠的土壤相比,在酸性和富含有机物的土壤中,秸秆回流所吸收的碳更多。机器学习随机森林(RF)算法表明,秸秆投放量是控制秸秆还田规模和效率的最重要单因素。然而,当地农业管理和环境条件共同决定了SR引起的SOC存量变化的空间差异。这需要通过优化环境条件良好的地区的农业管理,农民可以积累更多的碳,而负面影响很小。通过阐明多个局部因素的重要性和相对重要性,我们的研究结果可能有助于制定针对特定地区的秸秆还田政策,将SOC增量及其环境成本整合在一起。
    Enhancing soil organic carbon (SOC) through straw return (SR) has been widely recommended as a promising practice of climate-smart agriculture. Many studies have investigated the relative effect of straw return on SOC content, while the magnitude and efficiency of straw return in building up SOC stock remain uncertain. Here, we present an integrative synthesis of the magnitude and efficiency of SR-induced SOC changes, using a database comprising 327 observations at 115 sites globally. Straw return increased SOC by 3.68 ± 0.69 (95 % Confidence Interval, CI) Mg C ha-1, with a corresponding C efficiency of 20.51 ± 9.58 % (95 % CI), of which <30 % was contributed directly by straw-C input. The magnitude of SR-induced SOC changes increased (P < 0.05) with increasing straw-C input and experiment duration. However, the C efficiency decreased significantly (P < 0.01) with these two explanatory factors. No-tillage and crop rotation were found to enhance the SR-induced SOC increase, in both magnitude and efficiency. Straw return sequestrated larger amount of C in acidic and organic-rich soils than in alkaline and organic-poor soils. A machine learning random forest (RF) algorithm showed that the amount of straw-C input was the most important single factor governing the magnitude and efficiency of straw return. However, local agricultural managements and environmental conditions were together the dominant explanatory factors determining the spatial differences in SR-induced SOC stock changes. This entails that by optimizing agricultural managements in regions with favorable environmental conditions the farmer can accumulate more C with minor negative impacts. By clarifying the significance and relative importance of multiple local factors, our findings may aid the development of tailored region-specific straw return policies integrating the SOC increment and its environmental side costs.
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  • 文章类型: Journal Article
    在本研究中,我们研究了听觉数字和幅度(响度)对视觉数字处理的影响。参与者比较了两个连续点阵列的数量。第二个点阵列与独立于视觉比较的色调阵列配对。数字(单音与在实验1和2中分别操纵了多个音调)和非数值的音调(响度)。在实验1中,参与者的逆效率得分(IES),也就是说,响应时间和准确性之间的商,在单音和多音条件下明显小于无音条件下,线性趋势分析表明,IES随音调数量的增加而减少。在实验2中,大声音调条件下的IES明显小于无音调条件下的IES,IES随着音调响度的增加而降低。在实验3中,听觉数字和幅度都被操纵。对于柔和的色调,IES在多音条件下比在单音条件下要小,而两种情况在响亮的音调上没有发现显著差异。总之,这些发现表明,视觉数字表示可以自发地受到来自另一种模态的刺激的数量和非数值大小的影响。
    In the present study, we investigated the effects of auditory numerosity and magnitude (loudness) on visual numerosity processing. Participants compared numerosities of two sequential dot arrays. The second dot array was paired with a tone array that was independent of visual comparison. The numerosity (One-tone vs. Multiple-tone) and the non-numerical magnitude of tones (loudness) were manipulated in Experiments 1 and 2, respectively. In Experiment 1, participants\' inverse efficiency score (IES), that is, the quotient between response time and accuracy, was significantly smaller in the One-tone and Multiple-tone conditions than that in the No-tone condition, and linear trend analyses showed that the IES decreased with the number of tones. In Experiment 2, the IES in the Loud-tone condition was significantly smaller than that in the No-tone condition, and the IES decreased as the loudness of the tones increased. In Experiment 3, both auditory numerosity and magnitude were manipulated. For soft tones, the IES was smaller in the Multiple-tone condition than in the One-tone condition, whereas no significant difference was found between two conditions in loud tones. In sum, these findings suggest that the visual numerical representation can be spontaneously affected by the numerosity and non-numerical magnitude of stimuli from another modality.
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  • 文章类型: Journal Article
    研究了14名受试者在横向和侧倾方向上对正弦双轴振动的生物动力学响应。通过测量座板处的扭矩来检测人体响应的均方根。相位差的影响,量级,并研究了生物动力学响应的频率。研究了人类对双轴和单轴反应之间的一致性。随着相位差的增大,当振动反相时,发现人类的反应达到最大值,然后当振动同相时降低到最小值。此外,在双轴振动中证实了横向激励的优势。最后,建立了横向滚转双轴振动与横向滚转单轴振动的等效原理。使用等效方法,人体多轴振动的生物动力学特性有望用更简单的测试和动力学模型来测量和表示。医师总结:提议的等效性使用一个指标来评估由滚动和横向振动引起的复合不适。可以避免通过对它们单独计算的影响求和而导致的不适的高估。在等价之后,人体不适的评估和建模只能在滚动方向进行。
    The biodynamic response of 14 subjects to sinusoidal dual-axis vibration in lateral and roll directions is studied. The root mean square of human response is detected by measuring the torque at the seat pan. The effects of phase difference, magnitude, and frequency on the biodynamic responses are investigated. The consistency between human responses to dual-axis and single-axis is studied. With increasing phase difference, human response is found to reach the maximum when the vibrations are anti-phase and then decrease to the minimum when they are in-phase. Besides, the dominance of the lateral excitation is confirmed in the dual-axis vibration. Finally, the principle of equivalence between lateral-roll dual-axis vibration and roll single-axis vibration is established. With the equivalence method, the biodynamic characteristics of the human body to multi-axis vibration are expected to be measured and represented with a much simpler test and dynamic model.Practitioner summary: Proposed equivalence uses one index to evaluate the compound discomfort caused by the roll and lateral vibration. Overestimation of discomfort due by summing the effects of them calculated separately can be avoided. After the equivalence, evaluation of discomfort and modelling of the human body can be carried out only in roll direction.
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  • 文章类型: Systematic Review
    植物根系水力再分配(HR)已被广泛认为是一种有助于缓解植被干旱胁迫的现象。然而,在全球范围内缺乏对人力资源规模及其驱动因素的系统评估。我们收集了1900-2018年发表的37篇同行评审论文(包括47个研究站点),并全面分析了HR的大小及其潜在因素。我们使用加权方法来分析HR大小及其对植物蒸腾作用的影响。使用机器学习算法(增强回归树)和结构方程建模来确定每个因素对HR大小的影响。我们发现HR的大小为0.249mmH2Od-1(95%CI,0.113-0.384),其对植物蒸腾作用的贡献为27.4%(3-79%)。不同陆地生物群落之间的HR差异显着,主要发生在干旱条件下的森林中。如温带森林生态系统(HR=0.502mmH2Od-1),其中HR显著高于其他生态系统(p<0.01)。被子植物的HR值明显高于裸子植物(p<0.05)。随着湿度指数的增加,HR的平均幅度先增加后减少;相反,HR的平均大小随地下水位深度的增加而降低。HR与根长和蒸腾作用呈极显著正相关。植物特性和环境因子共同占HR变异的61.0%,植物蒸腾作用是直接影响HR的主要因素(相对重要性为43.1%;p<0.001),土壤质地是HR的重要间接驱动因素。我们的综合提供了植物特征和环境因素如何影响HR大小的全面视角。
    Plant root hydraulic redistribution (HR) has been widely recognized as a phenomenon that helps alleviate vegetation drought stress. However, a systematic assessment of the magnitude of HR and its drivers at the global scale are lacking. We collected 37 peer-reviewed papers (comprising 47 research sites) published in 1900-2018 and comprehensively analyzed the magnitude of HR and its underlying factors. We used a weighting method to analyze HR magnitude and its effect on plant transpiration. Machine learning algorithms (boosted regression trees) and structural equation modeling were used to determine the influence of each factor on HR magnitude. We found that the magnitude of HR was 0.249 mm H2O d-1 (95% CI, 0.113-0.384) and its contribution to plant transpiration was 27.4% (3-79%). HR varied significantly among different terrestrial biomes and mainly occurred in forests with drier conditions, such as temperate forest ecosystems (HR = 0.502 mm H2O d-1), where HR was significantly higher than in other ecosystems (p < 0.01). The magnitude of HR in angiosperms was significantly higher than that in gymnosperms (p < 0.05). The mean magnitude of HR first increased and then decreased with an increase in humidity index; conversely, the mean magnitude of HR decreased with an increase in water table depth. HR was significantly positively correlated with root length and transpiration. Plant characteristics and environmental factors jointly accounted for 61.0% of the variation in HR, and plant transpiration was the major factor that directly influenced HR (43.1% relative importance; p < 0.001), and soil texture was an important indirect driver of HR. Our synthesis offers a comprehensive perspective of how plant characteristics and environmental factors influence HR magnitude.
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  • 文章类型: Journal Article
    负数是否具有固定的响应代码效应(SNARC效应)的空间-数字关联,以及(如果有)负数的空间表示是否与负数的绝对值或符号值相关联仍然存在争议。在这项研究中,通过三个实验,幅度和空间方向的编码级别被操纵。在第一个实验中,参与者需要通过使用幅度分类任务来明确编码幅度和空间方向。在第二个实验中,参与者被迫通过使用提示任务来隐式地编码幅度以及显式地编码空间方向。在第三个实验中,参与者必须通过采用带有Go/No-Go响应的幅度和箭头方向分类任务来明确编码幅度,并隐式编码空间方向。结果表明:(1)当负数的大小被明确编码时,负数的绝对值与空间相关联,无论采用显式或隐式空间方向;(2)在隐式幅度和显式空间方向的条件下,负数的符号值与空间相关联。总之,目前的研究表明,负数的SNARC效应在不同条件下是可变的,关于负数的SNARC效应的类型由幅度和空间方向的联合编码级别调制。
    Whether negative numbers have a fixed spatial-numerical association of response codes effect (SNARC effect), and (if they have) whether the spatial representation of negative numbers is associated with negative numbers\' absolute or signed values remains controversial. In this study, through three experiments, the coding level of the magnitude and the spatial-direction is manipulated. In the first experiment, participants are required to code the magnitude and spatial-direction explicitly by using a magnitude classification task. In the second experiment, participants are forced to code the magnitude implicitly as well as to code the spatial-direction explicitly by utilizing a cuing task. In the third experiment, participants are obliged to code the magnitude explicitly as well as to code the spatial-direction implicitly by adopting a magnitude and arrow-direction classification tasks with Go/No-Go responses. The results show that (1) the absolute value of negative numbers associates with space when the magnitude of negative numbers is explicitly coded, no matter employing the explicit or implicit spatial-direction; (2) the signed value of negative numbers associates with space under the condition of implicit magnitude as well as explicit spatial-direction. In conclusion, the current study indicates that the SNARC effect of negative numbers is variable in different conditions, and the type of SNARC effect about negative numbers is modulated by the joint coding level of the magnitude and spatial-direction.
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  • 文章类型: Journal Article
    数值Stroop任务中的尺寸一致性效应表明,当数值较大的数字也以物理较大的尺寸出现时,两个数字的幅度判断更快,更准确,指示数值和物理量之间的相互作用。最近有人提出,两个数字之间注意力的空间转移可能会导致大小一致效应。然而,注意归因于大小一致性效应的完整证据仍有待建立。因此,本研究旨在进一步证明以下观点:在对两个数字的数值或物理尺寸进行幅度判断时,注意力的空间转移会导致尺寸一致性效应。参与者依次或同时获得一对数字阿拉伯数字,其数字和物理量独立变化。指示他们对配对数字的数值或物理大小进行幅度判断。在三个实验中,我们一致发现,当数字对依次呈现时,与同时呈现时相比,尺寸一致性效应降低或消除.因为在顺序呈现模式下,成对的数字是在中央固定时连续呈现的,因此空间注意力转移应该被数字刺激的中央呈现完全排除,目前的发现支持这样的观点,即同时呈现模式中数字之间注意力的空间转移在产生数字和物理任务的大小一致性效应中起着重要作用。
    The size congruity effect in a numerical Stroop task shows that magnitude judgments of two numbers are faster and more accurate when the numerically larger number also appears in a physically larger size, indicating the interaction between numerical and physical magnitudes. It has recently been suggested that spatial shifts of attention between the two numbers may contribute to the size congruity effect. However, a complete line of evidence for the attentional attribution to the size congruity effect remains to be established. Therefore, the present study aimed to provide further demonstrations for the idea that spatial shifts of attention contribute to the size congruity effect during magnitude judgments regarding either the numerical or physical dimension of two numbers. Participants were sequentially or simultaneously presented with a pair of single-digit Arabic numbers whose numerical and physical magnitudes varied independently. They were instructed to perform a magnitude judgment regarding the numerical value or physical size of the paired numbers. Across three experiments, we consistently found that the size congruity effect was reduced or eliminated when number pairs were presented sequentially compared to when they were presented simultaneously. Because in the sequential presentation mode the paired numbers were successively presented at central fixation and therefore spatial attention shifts should be completely precluded by the central presentation of number stimuli, the present findings support the notion that spatial shifts of attention between numbers in the simultaneous presentation mode play an important role in generating the size congruity effect for both numerical and physical tasks.
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  • 文章类型: Journal Article
    We examined how bees solve a visual discrimination task with stimuli commonly used in numerical cognition studies. Bees performed well on the task, but additional tests showed that they had learned continuous (non-numerical) cues. A network model using biologically plausible visual feature filtering and a simple associative rule was capable of learning the task using only continuous cues inherent in the training stimuli, with no numerical processing. This model was also able to reproduce behaviours that have been considered in other studies indicative of numerical cognition. Our results support the idea that a sense of magnitude may be more primitive and basic than a sense of number. Our findings highlight how problematic inadvertent continuous cues can be for studies of numerical cognition. This remains a deep issue within the field that requires increased vigilance and cleverness from the experimenter. We suggest ways of better assessing numerical cognition in non-speaking animals, including assessing the use of all alternative cues in one test, using cross-modal cues, analysing behavioural responses to detect underlying strategies, and finding the neural substrate.
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  • 文章类型: Journal Article
    BACKGROUND: To measure the crystalline lens tilt in eyes with various degrees of myopia before cataract surgery using swept-source optical coherence tomography (SS-OCT).
    METHODS: We used SS-OCT (IOLMaster 700) to scan 131 emmetropic eyes (axial length < 24.5 mm), 25 mild/moderate myopic eyes (axial length 24.5-26 mm), and 123 high myopic eyes (52, 29, and 42 eyes with axial lengths of 26-28, 28-30, and > 30 mm, respectively) as part of the routine preoperative examination before cataract surgery. SS-OCT involved B-scans along six meridians. The data were analyzed to assess the magnitude and orientation of the lens tilt and their correlation with other optical biometric parameters.
    RESULTS: The mean tilt was 3.36 ± 0.98° in emmetropic eyes, 3.07 ± 1.04° in mild/medium myopic eyes, and 2.35 ± 1.01° in high myopic eyes. Tilt correlated significantly and inversely with axial length (Pearson\'s r = - 0.427, P < 0.001). The crystalline lens tilt predominantly faced the upper outer quadrant relative to the visual axis, symmetrically in both eyes, with mean angles of 24.32° and 147.36° in the right and left eyes, respectively. The variability in the lens tilt direction increased with increasing axial length (χ2 test, P < 0.001).
    CONCLUSIONS: The magnitude of crystalline lens tilt decreased with increasing axial length. The direction of tilt was predominantly towards the upper outer quadrant in both eyes. The variability in the tilt orientation increased with increasing axial length.
    BACKGROUND: NIH (clinicaltrial.gov), NCT03062085. Registered 23 February 2017.
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  • 文章类型: Journal Article
    极端洪水的大小和频率基本上与水文设计中的风险和可靠性评估有关。极端洪水及其排放对区域气候变化高度敏感。目前,它的排放可以通过沿河谷的地质档案或记录来重建。在西波村(XPC)发现了两个典型的极端洪水沉积物(EFD)单元,这些沉积物承载了全新世黄土-古土壤序列中保存的长期信息,位于澄城县,中国。它位于北洛河(以下简称BLH)河的下游。基于多个沉积代理指数(粒度分布(GSD),磁化率(MS),和失燃(LOI),等。),EFD被解释为悬浮液中分选良好的黏土粉土。然后,由于在高水位期间在停滞的环境中河岸泛滥,它们被沉积。通过光学受激发光(OSL)测年技术和地层相关性,两个确定的极端洪水时期的年代学为7600-7400aB.P.和3200-3000aB.P.在气候异常情景下发生极端洪水的两个阶段的特征是河流系统中水文极端的频率很高。根据边坡面积法和水文工程中心河流分析系统(HEC-RAS)模型的模拟和验证,XPC站点的极端洪水排放在9625m3/s至16,635m3/s之间进行了重建。新的长期驱油频率和洪峰流量曲线,涉及到有测量的洪水,庄头站的历史洪水和就地重建的极端洪水事件,为下游BLH河建立。该结果提高了低频洪水风险评估的准确性,为预测河流系统对气候不稳定的响应提供了依据。因此,这改进了对BLH河流域的分析。
    Extreme flooding magnitudes and frequencies are essentially related to assessment of risk and reliability in hydrological design. Extreme flooding and its discharge are highly sensitive to regional climate change. Presently, its discharge can be reconstructed by a geological archive or record along the river valley. Two units of typical extreme flooding deposits (EFDs) carrying long-term information preserved in the Holocene loess-palaeosol sequence were found at Xipocun (XPC), which is located in Chengcheng County, China. It is situated in the downstream section of the Beiluohe (hereafter BLH) River. Based on multiple sedimentary proxy indices (grain-size distribution (GSD), magnetic susceptibility (MS), and loss-on-ignition (LOI), etc.), EFDs were interpreted as well-sorted clayey silt in suspension. They were then deposited as a result of riverbank flooding in a stagnant environment during high water level. Through the Optically Stimulated Luminescence (OSL) dating technique and stratigraphic correlations, chronologies of two identified extreme flooding periods were 7600-7400 a B.P. and 3200-3000 a B.P. Two phases of extreme flooding occurrence under climate abnormality scenarios were characterized as having high frequencies of hydrological extremes in river systems. According to simulation and verification using the Slope-Area Method and Hydrologic Engineering Center\'s River Analysis System (HEC-RAS) model, the extreme flooding discharges at the XPC site were reconstructed between 9625 m3/s and 16,635 m3/s. A new long-term flooding frequency and peak discharge curve, involved gauged flooding, historical flooding at Zhuangtou station and in situ reconstructed extreme flooding events, was established for the downstream BLH River. The results improve the accuracy of low-frequency flooding risk assessment and provide evidence for predicting the response of fluvial systems to climate instability. Thus, this improves the analysis of the BLH River watershed.
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