Subjects: Geosciences >> Geology submitted time 2023-08-23 Cooperative journals: 《中国科学院院刊》
Abstract： In order to implement the spirit of General Secretary Xi Jinping’s important speech on strengthening the comprehensive control of desertification and promoting key ecological engineering projects such as the “Three-North Shelterbelt Program”, this study is designated to make concrete efforts to win the battle against desertification on the edge of Hexi Corridor–Taklimakan Desert. The study deeply explores the situation of wind-blown sand flux and prevention tasks in the area. Based on the characteristics of desertified land and wind-blown sand activities on the edge of Hexi Corridor–Taklimakan Desert, the goal is set to effectively prevent the spread of sand and control dust sources. The core focus is on wind prevention, sand resistance, and dust control. The strategic thinking has been formulated for the counterattack battle on the edge of Hexi Corridor–Taklimakan Desert. By systematically analyzing the source areas and paths of “wind, sand, and dust” and targeting the key zones of the desert edge and areas requiring prevention, the key areas and tasks are proposed for desertification control on the edge of the Hexi Corridor–Taklimakan Desert, so as to provide scientific and technological support for winning the battle against desertification on the edge of Hexi Corridor–Taklimakan Desert.
Subjects: Statistics >> Social Statistics submitted time 2023-08-12 Cooperative journals: 《中国科学院院刊》
Abstract： In order to implement the spirit of General Secretary Xi Jinping’s important speech on strengthening the comprehensive control of desertification and promoting key ecological engineering projects such as the “Three-North Shelterbelt Program”, this study is designated to make concrete efforts to win the battle against desertification on the edge of Hexi Corridor–Taklimakan Desert. The study deeply explores the situation of wind-blown sand flux and prevention tasks in the area. Based on the characteristics of desertified land and wind-blown sand activities on the edge of Hexi Corridor–Taklimakan Desert, the goal is set to effectively prevent the spread of sand and control dust sources. The core focus is on wind prevention, sand resistance, and dust control. The strategic thinking has been formulated for the counterattack battle on the edge of Hexi Corridor–Taklimakan Desert. By systematically analyzing the source areas and paths of “wind, sand, and dust” and targeting the key zones of the desert edge and areas requiring prevention, the key areas and tasks are proposed for desertification control on the edge of the Hexi Corridor–Taklimakan Desert, so as to provide scientific and technological support for winning the battle against desertification on the edge of Hexi Corridor–Taklimakan Desert.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： Land degradation and desertification are the serious ecological problems and challenges to achieve global sustainable development goals. The Chinese government proposes to integrate the construction of the Silk Road Economic Belt with the environmental improvement of the Central Asia, to build an intimate community of shared destiny between China and the Central Asia countries, and to promote the green and sustainable development of the Silk Road Economic Belt. However, the ecological crisis in the Aral Sea causes a significant shrinking in water body, loss of biodiversity, salinization, desertification, and salt dust storm, which have become major environmental problems encountered in the construction of the Silk Road Economic Belt in the Central Asia. On the basis of sorting out the problems of land degradation and desertification caused by the ecological crisis in the Aral Sea,this study scientifically analyzed the development trend and causes of desertification and salinization land in the Aral Sea region in the past 30 years, discussed the spatial differences of vegetation stability and its carrying capacity in the Amu Darya Basin and the Aral Sea region, and put forward the directions, strategies, key technologies and innovative modes of ecological restoration for the desertification and salinized land. Solving the ecological crisis and desertification in the Aral Sea is one of the key points in the construction of the Green Silk Road, and also an important embodiment of building a community of shared future for mankind and practicing the global values of ecological civilization.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： The Belt and Road region crosses different geographic areas and ecological zones. Ecologic problems and hazards risks are complicated in these zones and they threat seriously the green development and economic corridors security along the Belt and Road region. Based on multiple data sources platform installation and experiment-demonstration researches and observations, the regional ecologic-environmental regulations of the Belt and Road region are well and scientifically recognized, key areas/zones and the ecologic-environmental security and risk response programmes of major projects are systematically integrated. The findings of the key advanced research project on the environment change and construction of the Green Silk Road of the Pan-Third Pole provide scientific and technical supports to the further promotion of the Green Belt and Road development, and they also serve the world successful cases for global environmental governance.
Subjects: Psychology >> Social Psychology submitted time 2023-03-27 Cooperative journals: 《心理学报》
Abstract： In China, disruptive sleep patterns and sleep deficiency are prevalent in preschool children. Literature has largely focused on the relationship between sleep duration and child development in adolescents and school-age children. Yet little is known about the impact of sleep duration in preschool children, for example, on their advanced neurocognitive function. Given that sleep need and sleep maturation develop rapidly in the first years of life, research findings in older children cannot be generalized to preschoolers.Developmental research indicates individual differences in sleep need. From a developmental perspective, it is crucial to explore whether children’s susceptibility to neurocognitive disruptions is associated with sleep problems. Temperament, one aspect of individual susceptibility, is shown to be relatively stable across situations and developmental periods. In this study, negative emotionality in preschool children was used to indicate temperament. The goal of this study was to examine the links between preschoolers’ initial sleep duration (i.e., total daily sleep duration, ratio of nighttime sleep to total daily sleep, and sleep compensation over the weekend) and later executive function and the moderating role of children’s negative emotionality in the links. The sample was composed of 78 preschool children (Mage = 6.31 years, SD = 0.35) and their mothers. Total daily sleep duration, ratio of nighttime sleep, sleep compensation over the weekend, and child negative emotionality were assessed using parental sleep diaries and mother reports. Child executive function was measured three months later using a set of standardized measurement procedures offered by the National Institutes of Health (NIH).The results of the present study indicated that controlling for children’s concurrent language ability, initial ratio of nighttime sleep significantly predicted children’s subsequent executive function. In addition, we found that negative emotionality significantly moderated the relation between sleep compensation and the three components of the executive function (working memory, inhibitory control, cognitive flexibility), in support of the differential susceptibility model. Specifically, sleep compensation was positively associated with performance in the executive function tests for preschool children with high negative emotionality whereas the association was nonsignificant for children with low negative emotionality. In conclusion, our findings suggested that children who sleep longer at night would be more advanced in their EF development. For children with high negative emotionality, sleep compensation over the weekend has a positive effect on their executive function skills. The results of this study provided important practical implications for Chinese preschoolers’ sleep arrangements.
Subjects: Biology >> Bioengineering submitted time 2018-03-13 Cooperative journals: 《中国生物工程杂志》
Abstract：目的 制备特异性抗人表皮生长因子受体(EGFR)的单链抗体（scFv），鉴定其生物学活性，为进一步研究基于单链抗体的免疫治疗奠定基础。方法 从分泌抗人EGFR单克隆抗体的杂交瘤细胞系提取总RNA，利用5’RACE技术扩增轻链和重链可变区（VL、VH）基因，构建具有VL、VH基因的单链抗体基因，并将构建的单链抗体基因克隆到真核细胞表达载体pcDNA3.1中进行表达和鉴定。ELISA鉴定单链抗体对抗原的特异性；Fortebio检测抗原抗体间的亲和力，流式细胞术检测单链抗体结合肺癌细胞系天然EGFR的功能活性。结果 获得唯一的轻重链可变区序列VL、VH，成功构建EGFR-scFv，特异性与天然EGFR蛋白结合，亲和力达3.22×10-9mol/L。结论 成功构建了抗人EGFR单链抗体，为肺癌免疫导向治疗研究奠定了基础。
Subjects: Biology >> Ecology submitted time 2017-11-29 Cooperative journals: 《中国生态农业学报》
Abstract： To achieve the optimum tillage depth of 22cm and soil bulk density of 1.1~1.3 g譪m-3 of topsoil layer for maize production, and solve the farmland soil structure issue of shallow topsoil layer (16cm), hard (bulk density 1.55~1.62 g譪m-3) and thick (45 cm) plow pan in Inner Mongolia Plain irrigation. The study was conducted on the four-year location experiment of deep tillage maize straw manure after harvest, the annual average maize straw returned to soil was 20�34.79 kg議m-2 and four experiment treatments (SF1-SF4) of deep tillage maize straw manure from one to four years and a control group (CK) of non-deepening straw were formed year by year. Result 1, it showed that in 0-40 cm layer soil, the average value of bulk density (SF1-SF4) was significantly reduced by 11.38%, 12.28%, 15.30% and 15.50% compared with CK, and the average value of soil compaction (SF1-SF4) was significantly decreased by 1�36 kPa, 1�63 kPa, 1�36 kPa and 1�55 kPa compared with CK. Result 2, it showed that in 0-20 cm layer, SF4 of more than 0.25mm aggregate content and geometric mean diameter was significantly reduced by 13.79% and 27.21% compared with CK; SF3 and SF4 of the mean weight diameter of aggregates was reduced by 8.25% and 19.59% compared with CK; SF1 of the damage rate of soil aggregates was significantly decreased by 9.56% compared with CK; SF1 of the sabotage water-stable aggregates was reduced by 9.56% compared with CK, SF4 of the fractal dimension of aggregates was significantly increased by 7.30% compared with CK. Result 3, it showed that in 20~40 cm layer, SF1 and SF2 of more than 0.25 mm aggregate content was significantly increased by 13.69% and 17.83% compared with CK; SF2 of the mean weight diameter and geometric mean diameter of aggregates was significantly increased by 23.92% and 53.38% compared with CK; SF1~SF4 of the damage rate of soil aggregates was significantly decreased by 9.20%, 3.02%, 8.38% and 3.16% compared with CK; SF1-SF4 of the sabotage water-stable aggregates was significantly increased by 13.58%, 16.49%, 22.67% and 25.42% compared with CK, SF2 of the fractal dimension of aggregates was significantly decreased by 7.39% compared with CK. Result 4, it showed that SF1~SF4 of the soil organic matter was significantly increased by 16.32%, 24.78%, 25.07% and 25.56% compared with CK; SF1-SF4 of the available nitrogen was significantly increased by 16.86%, 14.46%, 17.20% and 21.95% compared with CK; SF1~SF4 of the available phosphorus was significantly increased by 6.8%, 12.07%, 17.85% and 23.30% compared with CK; SF1~SF4 of the available potassium was significantly increased by 17.59%, 16.34%, 20.49% and 29.85% compared with CK; SF3 and SF4 of the soil pH was significantly decreased by 1.95% and 1.73%. There was a significant effect of deep tillage maize straw manure from one to four years on the soil structure of 0-40 cm soil layer. 2-year deep tillage maize straw manure was most suitable for improving the structure of soil plow pan; 3-year and 4-year deep tillage maize straw manure were most suitable for improving the structure of topsoil layer. In the application of deep tillage maize straw manure, it should be noted that the depth of plowing was 40cm, which should be reduced by 30 cm two years later. The reason was that the damage rate of soil aggregates of plow pan and the sabotage water-stable aggregatess were increased by the continuous 40cm deepening and the damage of soil plow pan structure was aggravated; the depth of plowing was reduced by 20cm, which maintained deep tillage maize straw manure on topsoil layer, the decomposition of straw and soil organic matter were increased, the damage rate of soil aggregates was decreased, and the sabotage water-stable aggregatess was decreased, which was conducive to cultivating topsoil layer.
Subjects: Materials Science >> Materials Science (General) submitted time 2017-03-31 Cooperative journals: 《金属学报》
Abstract：采用X射线衍射测定了GH3625合金热挤压管材在不同冷变形量下经过800 ℃下时效后δ相的析出含量，并用扫描电子显微镜（SEM）、能谱分析（EDS）及Image-Pro Plus金相分析软件等手段，研究了冷变形对δ相的析出规律及析出动力学的影响。结果表明，δ相首先在形变孪晶界、晶界以及变形带上形核并析出，随后在晶内形核并长大，并且随冷变形量的增加，δ相在变形带上析出量增加；随冷变形量的增加，δ相的形貌从针状向棒状或颗粒状转变；随着时效时间的延长，δ相的平均尺寸不断增大，并且长大规律符合LSW理论；当时效温度为800 ℃时，δ相的析出的含量与时效时间的关系满足Avrami方程，且随冷变形量的增加，δ相的含量增加，n值减小，α值增加，冷变形促进δ相的析出；Nb的溶质拖曳与δ相的钉扎共同作用抑制晶粒长大，其合金的硬度随保温时间的延长ε=35 %时增加，ε≥50 %时未发生明显变化。
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