我国学前教育高质量发展的多组态路径——基于DPSIR框架的模糊集定性比较分析(fsQCA)

文章基于DPSIR框架设计评价指标体系对区域学前教育高质量发展水平进行评价,以熵权-TOPSIS计算指标权重和综合得分,结合模糊集定性比较分析(fsQCA)进行组态路径分析。研究发现:(1)我国学前教育高质量发展水平呈现由东向西递减的趋势,除东部外,中部与西部区域学前教育高质量发展水平均值均低于全国均值;(2)基于DPSIR框架的区域学前教育发展系统驱动学前教育高质量发展具有“多重并发”与非对称性的特点;(3)存在两条高水平组态路径与3条非高水平组态路径,多条组态路径殊途同归,且高水平组态与非高水平组态处于非对称状态;(4)东部、中部与西部组态路径存在一定差异,三大区域学前教育高质量发展均离不开状态因子与响应因子的支持。为此,要完善机制体制建设,为学前教育发展提供保障;因地制宜制定发展策略,以协同路径驱动学前教育高质量发展;聚焦区域重点,以重点发展引领区域学前教育高质量发展。

Application of Multivariate Analysis for Identification of Pollution Sources in the Densu Delta Wetland in the Vicinity of a Landfill Site in Ghana

Surface water samples collected from various sites in the Densu delta wetland, Ghana, were analyzed for pH, temperature, TDS, EC, turbidity, TSS, alkalinity, HCO3-, BOD, COD, Na, K, Mg, Ca, Cl, SO42-, PO4-P, NO3-N, Cr, Pb, Cd, Cu, Co and Fe using titration and Atomic Absorption Spectrometer (AAS). Multivariate statistical analyses such as cluster analysis (CA) and principal component analysis (PCA) were used to identify heavy metal pollution in the wetland area. Results from CA and PCA suggest positive relationships between the two analyses. Linear correlation analysis done also suggests similar relationships. Heavy metals were identified as originating from a common source in all the analyses. The hydrochemistry of the area appears to have been influenced, to a large extent, by dissolution/precipitation as well as numerous but subsistence small-scale agricultural activities that take place in the wetland environment.

基于CRISPR/Cas系统的纸基分析在快速检测食源性致病菌中的应用

由食源性致病菌引起的食品安全事件严重影响人类健康,开发针对食源性致病菌的快速检测技术十分必要。成簇间隔短回文重复序列(clustered regularly interspaced short palindromic repeats,CRISPR)及相关蛋白(CRISPR-associated protein,Cas)是原核生物的适应性免疫系统,具有特异性识别并切割核酸序列的功能。纸基分析方法作为一种简便性好、成本低廉的分析检测工具,在快速检测领域展现出良好的前景。因此,将CRISPR/Cas系统的高效识别能力和纸基分析方法的简便性相结合可实现对食源性致病菌的快速灵敏检测。本文简要介绍了CRISPR/Cas系统用于核酸检测的概况,对第二类单Cas效应蛋白系统的特点及原理进行概述,重点综述基于CRISPR/Cas系统的试纸分析、侧向流动分析和纸基微流控装置在检测食源性致病菌方面的应用,并讨论了CRISPR/Cas系统结合纸基分析建立检测方法的优势、当前的挑战及未来的发展前景。

Relationship of public preferences and behavior in residential outdoor spaces using analytic hierarchy process and principal component analysis—a case study of Hangzhou City, China

This study examined public attitudes concerning the value of outdoor spaces which people use daily. Two successive analyses were performed based on data from common residents and college students in the city of Hangzhou, China. First, citizens registered various items constituting desirable values of residential outdoor spaces through a preliminary questionnaire. The result proposed three general attributes (functional, aesthetic and ecological) and ten specific qualities of residential outdoor spaces. An analytic hierarchy process (AHP) was applied to an interview survey in order to clarify the weights among these attributes and qualities. Second, principal factors were extracted from the ten specific qualities with principal component analysis (PCA) for both the common case and the campus case. In addition, the variations of respondents’ groups were classified with cluster analysis (CA) using the results of the PCA. The results of the AHP application found that the public prefers the functional attribute, rather than the aesthetic attribute. The latter is always viewed as the core value of open spaces in the eyes of architects and designers. Fur-thermore, comparisons of ten specific qualities showed that the public prefers the open spaces that can be utilized conveniently and easily for group activities, because such spaces keep an active lifestyle of neighborhood communication, which is also seen to protect human-regarding residential environments. Moreover, different groups of respondents diverge largely in terms of gender, age, behavior and preference.

茶树OSCA基因家族的鉴定及表达分析

钙通透性阳离子通道蛋白(OSCA)在植物调节高渗胁迫中发挥着重要作用。为了解OSCA基因家族在茶树响应干旱胁迫中的作用,本研究基于茶树全基因组数据对OSCA基因家族进行鉴定,分析CsOSCAs基因和蛋白结构以及启动子顺式作用元件,并对CsOSCAs在茶树不同组织、不同抗旱性品种间和干旱胁迫下的表达模式进行分析。结果表明:茶树基因组包含12个OSCA基因家族成员,分别命名为CsOSCA1~CsOSCA12;CsOSCAs基因编码的氨基酸序列长度为667~831 bp,蛋白分子量在76630.55~93563.99 kDa之间,等电点在6.15~9.33之间,含有9~12个跨膜结构域,均含有特征保守结构域DUF221,根据系统进化关系可以分为4个亚族;10个CsOSCAs基因定位于茶树7条染色体上,2个CsOSCAs基因定位于未锚定染色体的contig上;CsOSCAs基因编码的蛋白二级结构含有32%~38%的跨膜结构和60%~68%的α-螺旋;CsOSCAs基因具有组织表达特异性,CsOSCA2、CsOSCA3、CsOSCA11、CsOSCA12基因在干旱敏感的品种CN98中的表达量显著高于其他2个耐旱品种,9个基因响应PEG胁迫,其中CsOSCA2、CsOSCA3、CSOSCA5、CsOSCA8、CsOSCA10和CsOSCA12受干旱胁迫强烈诱导;进一步分析启动子顺式作用元件显示,6个基因含有干旱诱导响应元件,11个基因含有脱落酸响应元件。由此推测茶树OSCA基因家族在茶树响应干旱胁迫中发挥着重要的作用,此研究为茶树OSCA基因功能分析与茶树抗逆性研究提供参考。

Non-Isothermal Kinetic Analysis of Thermal Decomposition of the Ca-Bentonite from Santai, China

The thermal decompositions of Ca-bentonites (CaB) from Santai ,Shichuan Province, China over the temperature rage of 30-1100℃ were investigated by simultaneous thermal analyzer. Non-isothermal Kinetic analysis were employed to study the thermal decomposition mechanism by using Netzsch Thermokinetics software. The dependence of the activation energy on conversion degree were evaluated by isoconversional methods. The probably mechanism and the corresponding kinetic parameters were determined by multivariate non-linear regression program.

Identification and Validation of Novel Biomarkers Related to the Calcium Metabolism Pathway in Hypertension Patients Based on Comprehensive Bioinformatics Methods

Background: Hypertension is a universal risk factor for cardiovascular diseases and is thus the leading cause of death worldwide. The identification of novel prognostic and pathogenesis biomarkers plays a key role in disease management. Methods: The GSE145854 and GSE164494 datasets were downloaded from the Gene Expression Omnibus (GEO) database and used for screening and validating hypertension signature genes, respectively. Gene Ontology (GO) enrichment analysis was performed on the differentially expressed genes (DEGs) related to calcium ion metabolism in patients with hypertension. The core genes related to immune infiltration were analyzed and screened, and the activity of the signature genes and related pathways was quantified using gene set enrichment analysis (GSEA). The infiltration of immune cells in the blood samples was analyzed, and the DEGs that were abnormally expressed in the clinical blood samples of patients with hypertension were verified via RT-qPCR. Results: A total of 176 DEGs were screened. GO showed that DEGs was involved in the regulation of calcium ion metabolism in biological processes (BP), actin mediated cell contraction, negative regulation of cell movement, and calcium ion transmembrane transport, and in the regulation of protease activity in molecular functions (MF). KEGG analysis revealed that the DEGs were involved mainly in the cGMP-PKG signaling pathway, ubiquitin-protein transferase, tight junction-associated proteins, and the regulation of myocardial cells. MF analysis revealed the immune infiltration function of the cells. RT-qPCR revealed that the expression of Cacna1d, Serpine1, Slc8a3, and Trpc4 was up regulated in hypertension, the expression of Myoz2 and Slc25a23 was down regulated. Conclusion: Cacna1d, Serpine1, Slc8a3, Trpc4, Myoz2 and Slc25a23 may be involved in the regulation of calcium metabolism pathways and play key roles in hypertension. These differentially expressed calcium metabolism-related genes may serve as prognostic markers of hypertension.

基于CA-Markov模型的土壤侵蚀预测分析——以宜昌市为例

本研究介绍了CA-Markov模型预测土地侵蚀的方法,分析了宜昌市2000年、2010年和2020年三期的土壤侵蚀强度空间分布数据,提出以这三期数据作为预测基准年,利用CA-Markov模型进行精度验证后来预测宜昌市2030年土壤侵蚀情况,并在此基础上分析宜昌市2030年土壤侵蚀强度空间分布及土壤侵蚀发展趋势。结果表明:宜昌市2030年土壤侵蚀情势总体向好发展,水土流失面积与强度呈现“双下降”态势,水土流失面积下降至2493.6km~2;秭归县、当阳市、兴山县等区域土壤侵蚀情势仍然不容乐观,高强度侵蚀面积出现净增长,仍是未来水土保持的工作重点。

Seismic reliability assessment of a steel moment-resisting frame with two different ductility levels using a cloud analysis approach

A cloud method for generating percentile engineering demand parameter versus intensity measure(EDP-IM) curves of a structure subjected to a set of synthetic ground motions is presented. To this end, an ensemble of synthetic ground motions based on available real ones is generated. This is done by using attenuation relationships, duration and suitable Gutenberg-Richter relations attributed to the considered seismic hazard at a given site by estimating a suitable distribution of magnitude and site to source distance. The study aims to clarify the significance of the duration and frequency content on the seismic performance of structures, which were not considered in developing percentile incremental dynamic analysis(IDA) curves. The collapse probabilities of two steel moment-resisting frames with different ductility levels generated by IDA and the proposed cloud method are compared at different intensity levels. When compared with conventional IDA, the suggested cloud analysis(SCA) methodology with the same run number of dynamic analyses was able to develop response hazard curves that were more consistent with site-specific seismic hazards. Eliminating the need to find many real records by generating synthetic records consistent with site-specific seismic hazards from a few available recorded ground motions is another advantage of using this scheme over the IDA method..

基于CA-Markov和MSPA的绿色基础设施预测与时空演变分析——以京津冀城市群为例

绿色基础设施(Green Infrastructure,GI)的合理布局有助于建立国土空间绿色发展新模式。在生态文明和高质量发展背景下,研究GI长时序时空双维度演变格局对提升生态环境质量、提高国土空间治理能力和实现“碳中和”目标具有重要意义。基于CA-Markov(Cellular Automata-Markov,CA-Markov)、MSPA(Morphological Spatial Pattern Analysis,MSPA)和景观格局分析方法等构建GI研究模型框架,实现对GI过去—现在—未来的时空双维度分析。以京津冀城市群为研究区,分析了2000—2020年GI时空双维度演化特征,预测了未来2025和2030年的发展态势,讨论了协同发展过程与GI格局演变的对应关系,并总结GI优化启示。结果表明:(1)2000—2020年,GI面积占研究区总面积的比例呈现逐年下降趋势,由90.82%降为86.60%,空间上表现为西北部密集、东南部稀疏的分布态势。核心作为GI的主要组成部分,面积占比57.04%—65.93%不等,同样呈现逐年下降趋势,其主要分布在研究区北部、西部和西北部。(2)2020—2030年,研究区GI面积小幅度下降,但核心面积占比增长明显,2030年占比高达84.04%。连接桥、边缘和环等其他GI类型面积占比较小,其分散分布在各核心之间。(3)城市群协同发展进程提速直接导致GI的波动,主要体现在2015—2020年实质发展期和2020—2025年国土空间规划加速落实期。(4)未来,京津冀城市群GI生态网络稳定性的提升需重点关注各城市中心GI的面积占比和东南部的连通性问题。研究结果为快速实现GI检查、评估和治理提供技术支撑,也有助于实现京津冀城市群建立绿色、低碳、可持续发展新模式。

Effect of addition of minor amounts of Sb and Gd on hot tearing susceptibility of Mg-5Al-3Ca alloy

The effects of addition of minor amount of(0.5 wt.%) antimony(Sb) or gadolinium(Gd) and combined addition of Sb and Gd(0.5 wt.%,respectively) on the hot tearing susceptibility(HTS) of Mg-5Al-3Ca alloy were investigated experimentally using a “T-shaped” hot tearing measuring system. Various solidification parameters of the alloys were measured and calculated through thermal analysis experiments. The microstructure, grain size, and morphology of the crack zone were characterized by scanning electron microscopy and electron backscatter diffraction, and the crystal phases of the alloys were analyzed by X-ray diffraction and energy-dispersive X-ray spectroscopy. The results showed that the addition of 0.5 wt.% Gd resulted in the increase in the vulnerable temperature range(Tv) and reduced the eutectic structure content that could participate in feeding, thereby improving the HTS of the alloy. However, addition of 0.5 wt.% Sb or combined addition of Gd and Sb(0.5 wt.%, respectively) to the Mg-5Al-3Ca alloy shortened the Tvand improved the skeleton strength of the alloy, thereby reducing HTS. Moreover, significantly refined structure of Mg-5Al-3Ca-0.5Gd-0.5Sb alloy improved the feeding ability of the eutectic structure, thus the alloy exhibited the lowest HTS.

煤泥浮选中Ca^(2+)吸附对高岭土和石英抑制作用的研究

为探清Ca^(2+)对煤泥中其他杂质矿物的抑制作用,改善浮选效果,采用CaCl_(2)为抑制剂,柴油为捕收剂,松醇油起泡剂,探索实验得到柴油和松醇油最佳用量分别为1000 g/t和300 g/t。利用煤泥浮选和人工混合矿浮选考察了Ca^(2+)对煤泥中高岭土和石英的抑制效果,浮选实验均采用单元浮选实验流程,人工混合矿为4 g纯煤与1 g高岭土或1 g石英的混合矿。浮选实验开始前矿浆中分别加入0 mmol/L,2 mmol/L,4 mmol/L,6 mmol/L,8 mmol/L,10 mmol/L的CaCl_(2)溶液。结果显示:煤泥浮选中Ca^(2+)浓度由0 mmol/L增加到4 mmol/L时,可燃体回收率增加了8.24%,抑制效果明显,Ca^(2+)浓度大于4 mmol/L时,精煤灰分含量显著提高,不利于浮选;纯煤与高岭土混合矿浮选时,随着Ca^(2+)浓度增加,可燃体回收率一直保持稳定上升趋势,回收率从87.16%增加至96.18%;纯煤与石英混合矿浮选时,Ca^(2+)浓度增加到4 mmol/L后,可燃体回收率在91%上下波动且精煤灰分含量开始明显增加;通过粒度分析、Zeta电位测试研究Ca^(2+)吸附对高岭土和石英抑制机理,发现Ca^(2+)浓度由0 mmol/L增加到10 mmol/L时,高岭土粒径和石英粒径分别增加了0.71μm和0.84μm,高岭土和石英Zeta电位绝对值分别降低了10.57 mV和7.98 mV,矿物颗粒之间静电斥力减弱,更易聚集;浓度适中的Ca^(2+)对高岭土和石英抑制效果较好,浓度过低的Ca^(2+)对高岭土和石英抑制效果不明显,浓度过高的Ca^(2+)会导致煤泥浮选选择性降低,精煤灰分含量升高,浮选效果变差。

A CSMA/CA based MAC protocol for hybrid Power-line/Visible-light communication networks:Design and analysis

Hybrid Power-line/Visible-light Communication(HPVC)network has been one of the most promising Cooperative Communication(CC)technologies for constructing Smart Home due to its superior communication reliability and hardware efficiency.Current research on HPVC networks focuses on the performance analysis and optimization of the Physical(PHY)layer,where the Power Line Communication(PLC)component only serves as the backbone to provide power to light Emitting Diode(LED)devices.So designing a Media Access Control(MAC)protocol remains a great challenge because it allows both PLC and Visible Light Communication(VLC)components to operate data transmission,i.e.,to achieve a true HPVC network CC.To solve this problem,we propose a new HPC network MAC protocol(HPVC MAC)based on Carrier Sense Multiple Access/Collision Avoidance(CSMA/CA)by combining IEEE 802.15.7 and IEEE 1901 standards.Firstly,we add an Additional Assistance(AA)layer to provide the channel selection strategies for sensor stations,so that they can complete data transmission on the selected channel via the specified CSMA/CA mechanism,respectively.Based on this,we give a detailed working principle of the HPVC MAC,followed by the construction of a joint analytical model for mathematicalmathematical validation of the HPVC MAC.In the modeling process,the impacts of PHY layer settings(including channel fading types and additive noise feature),CSMA/CA mechanisms of 802.15.7 and 1901,and practical configurations(such as traffic rate,transit buffer size)are comprehensively taken into consideration.Moreover,we prove the proposed analytical model has the solvability.Finally,through extensive simulations,we characterize the HPVC MAC performance under different system parameters and verify the correctness of the corresponding analytical model with an average error rate of 4.62%between the simulation and analytical results.

基于空间模型和CA的城市用地扩展模拟研究——以大庆市为例

基于ArcGIS空间分析建模工具,将城市发展适宜性模块、邻域影响模块、约束影响模块、随机影响模块进行集成,实现CA模型的构建,并以大庆市为例对城市建设用地未来发展进行模拟。研究认为:(1)将GIS空间分析和CA模型集成,模型结构清晰,避免二次程序开发;(2)根据大庆市特点,考虑资源开发因素对城市发展的影响和人口增长对随机因素的影响;(3)大庆市2015、2020年城市面积将继续扩展,城市重心将明显向北移动,并具有向东移动的趋势。

基于CA-Markov模型的藉河流域土地利用变化动态模拟

为了探讨黄土丘陵沟壑区藉河流域的土地利用变化规律及驱动力,基于1995和2008年两期遥感影像解译得到的土地利用数据,通过土地利用动态度模型和空间测算模型对藉河流域土地利用类型的动态变化程度进行分析,并运用CA-Markov模型对2022年土地利用空间格局进行预测。结果表明,空间分析测算模型由于同时考虑了各土地利用类型的空间转移及新增过程,能更为准确地测算出各种土地利用类型的动态变化程度与速率;CA-Markov模型预测结果表明,整个流域总体的Kappa系数为0.9515,预测结果可信;除草地和未利用地外,2008-2022年期间其他土地利用类型继续原有的变化趋势,到了2022年表现出坡耕地、草地、水域和未利用地面积减少趋势,梯田、林地和居民地面积呈增加趋势。黄土丘陵沟壑区水土流失严重,此研究有助于加强土地资源的保护和实施退耕还林还草等措施,为当地土地利用规划管理提供参考。

Mg-Ca合金表面氧化行为的研究

研究了几种不同Ca含量的Mg Ca二元合金表面氧化程度及其氧化膜形貌。合金表面氧化膜的XRD ,SEM ,TEM及其电子探针分析表明 ,Ca元素的加入可有效地减少镁合金熔体表面的氧化 ,且随着Ca含量的增加 ,氧化程度减弱 ,表面品质变好。含Ca镁合金熔体氧化膜由外到内分为MgO层、CaO层和MgO·CaO层。还从热力学角度探讨了Ca元素的阻燃机理。

基于CA-Markov模型的挠力河流域土地利用动态模拟

以三江平原腹地挠力河流域为研究对象,基于1990和2013年2期遥感数据,结合马尔科夫(Markov)转移矩阵、土地利用动态度模型和土地利用程度模型分析流域1990—2013年土地利用变化情况,运用CA-Markov模型对2025年土地利用格局进行模拟预测。结果表明:流域土地利用结构变化以耕地的内部和外部转换为主,水田化现象是最主要的景观变化特征,未利用地面积由于大量垦荒而大幅度减少;土地利用程度指数由1990年的251.46上升至2013年的270.48,土地开发利用程度不断加大;模型模拟显示流域Kappa系数为0.82,预测结果可信;2013—2025年流域土地利用类型变化趋势和速率与1990—2013年存在差异,林地变化幅度最大,水田面积仍然保持增长,但增长速度有所下降,单一动态度降为2%,旱地面积基本保持不变;未来12 a土地利用程度指数持续上升,流域受人类社会因素扰动作用的强度将会进一步加大。

基于CA-Markov模型的乌江下游地区土地利用变化情景分析

以乌江下游的涪陵等6个区县为研究区,基于1995年、2005年、2015年的Landsat影像解译数据,综合运用GIS空间分析技术、CA-Markov模型和MCE模型,实现研究区土地利用时空格局模拟。结合情景分析方法,探讨在"快速城镇化情景"、"现状延续情景"和"生态保护情景"三种模式下研究区2020年、2035年、2050年的土地利用格局。结果表明:(1)在"快速城镇化情景"下,建设用地急剧扩张,35年间其面积增加了一倍,达到1 390.46km2,且主要来源为耕地,约占转出耕地面积的一半;林地增长十分缓慢,草地和未利用地持续减少,到2050年分别减少了186.58km^2和69.40km^2,未利用地减少了一半。(2)在"现状延续情景"下,建设用地增长仍然较快,2050年增加了347.92km^2,增幅达37.92%;耕地减幅有所下降,林地增加也比"快速城镇化情景"要快,但草地和未利用地仍在持续减少,35年间分别减少了25.9%和44.3%。(3)在"生态保护情景"下,林地、草地、未利用地等生态用地不断恢复和增加,到2050年,生态用地总面积占研究区的64%;建设用地无序扩张得到限制,到2050年其总面积为1 171.42km^2,比同期"快速城镇化情景"减少了219.04km^2;耕地虽有减少,但逐渐趋于平衡,始终保持在6 000km^2以上。因此,"生态保护情景"是研究区未来经济、社会和环境协调发展较为理想的模式。研究结果可为该地区土地规划、区域可持续发展提供科学参考。