Subjects: Statistics >> Social Statistics submitted time 2024-05-18 Cooperative journals: 《中国科学院院刊》
BIAN Wenyue
LIANG Xingjie
GE Chunlei
HUI Zhongyang
JIA Xiaoqi
LIU Si
YE Jing
CHEN Xiaoyi
WANG Wenjun
JU Huajun
Abstract： Nanoscale science and technology (nano S&T) are at the frontier of global strategic high-tech competition. After examining nearly 160 strategy and planning documents released by scientific and technological powerhouses from 2000 to 2023, the study finds ten common approaches adopted by the powerhouses to advance nano S&T as follows. (1) Recognizing nano S&T as a key area for the economy and global competition. (2) Establishing cross-department organizations to meet the cross-disciplinary nature of nano S&T. (3) Developing strategic plans to guide the development of nano S&T and implementing major programs with significant investment. (4) Establishing multidisciplinary nano S&T research centers based upon institutions with strength. (5) Building and maintaining physical and cyber R&D infrastructures for nano S&T. (6) Promoting convergence of nanotechnology, information technology, biotechnology, and cognition science. (7) Establishing facilities to accelerate the commercialization of promising discoveries. (8) Paying close attention to the possible effects of nano S&T on the environment and human health. (9) Developing a skilled workforce and recruiting overseas talents. (10) Engaging in international collaborations. The study also finds that the powerhouses have continued to pay close attention to nano S&T during the past three years, focusing on issues such as leveraging nano S&T to help address significant societal challenges and preparing for the oncoming data-intensive R&D paradigm. Moreover, the study discusses the progress and shortcomings of nano S&T in China and proposes suggestions for R&D in the future after taking account of the findings presented above. The suggestions include promoting the commercialization of promising R&D, building and maintaining nanomaterial databases, establishing nano S&T think tanks, and putting in place a system of developing talent who can adapt to scientific and technological trends and meet the demands of the development of nano S&T.
Subjects: Biology >> Botany submitted time 2022-10-27 Cooperative journals: 《广西植物》
Abstract： Phalaenopsis was the genus with the highest ornamental value and the best commercialization among orchids. Phalaenopsis with fragrance were rarely distributed in the market due to selection constraints, such as affinity, ploidy and breeding age. Researching on floral fragrance and transferring aroma traits into commercial Phalaenopsis are of great significance to the breeding of Phalaenopsis floral fragrance. In order to investigate the key aroma-causing components among different varieties of Phalaenopsis, the floral fragrance components of the eight new hybrid varieties in full blooming period were examined by headspace solid-phase microextraction and gas chromatography-mass spectrometry. The principal components, clustering and aroma quality analysis were performed based on the identification of floral substance components. The results were as follows: (1) 96 substances were detected in eight varieties of Phalaenopsis, mainly divided into eight categories of terpenes, aldehydes, esters, alcohols, ketones, ethers, phenols and aromatic compounds, among which terpenes were dominant in quantity and content and were the main volatile substances of Phalaenopsis. (2) Principal component analysis showed that eight varieties were divided into three quadrants. F2 had the most volatile components and the most quantity, terpenes were mainly 1,8-cineole, α-bergamotene, linalool and (+)-calarene; F1, F4, F5 and F8 were divided into a group without ketones, ethers or phenols, and they had the least volatile components and terpenes were mainly linalool; F3, F6 and F7 were divided into a group with more volatile components and the terpenes were mainly α-bergamotene. (3) The results of cluster analysis were consistent with the principal component analysis, and the eight varieties were clustered into three categories. F1, F4, F5 and F8 were more closely related to each other as floral odor types; F3, F6 and F7 were more closely related to each other as woody floral quality; F2 showed a long genetic distance from the other seven varieties, with complex floral components and relatively average contribution of volatile substances, and both woody, minty and fruity types. This study shows that floral fragrance substances can be used as potential trait markers to distinguish between groups of varieties with different fragrance characteristics and provide a theoretical basis for further development and utilization research through cross selection to achieve specific floral fragrance Phalaenopsis selection and product processing and production.
Subjects: Geosciences >> Geography submitted time 2021-06-13 Cooperative journals: 《干旱区研究》
Abstract：锡林郭勒草原是我国北方典型的干旱半干旱牧区，利用1959—2017年研究区不同地理位置逐日气温和降水数据，通过计算潜在蒸散量和水分盈亏量，结合趋势分析和R/S极差分析等方法，研究干旱半干旱牧区气候因子的时空分布特征及变化趋势，为北方牧区干旱的监测和预测提供科学支撑。研究表明：过去59 a，锡林郭勒草原气温呈显著增加趋势［0.39 ℃·(10a)-1］，降水呈缓慢减小趋势［-5.40 mm·(10a)-1］，气候逐渐趋于暖干化。研究区东南部的降雨量明显高于西北部，水分亏缺量由西向东逐渐递减，气温和潜在蒸散量则呈西南高、东北低的空间分布；不同地理位置关键致灾气候因子的年际变化差异显著，年内呈单峰型周期性变化，于7月份达到水热条件良好状态。锡林郭勒草原暖干化趋势的正持续性强烈，西部二连浩特地区荒漠化风险严重，东部西乌珠穆沁旗和中北部那仁宝力格地区降雨和水分盈亏量下降趋势显著，会对植被生长和生态环境产生不利影响。
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2019-09-11 Cooperative journals: 《干旱区研究》
Abstract：利用1971—2015年内蒙古地区52个气象站逐月降水量观测数据，采用降水量距平百分率(Pa)，从干旱频率和干旱变化趋势率分析了研究区近45 a来干旱时空分布特征。结果表明：从时间变化来看，年降水量呈微弱的下降趋势，并于1998年和2012年发生突变；春季、秋季和冬季降水量变化呈上升趋势，夏季降水量变化呈下降趋势；年尺度干旱主要发生在1999—2011年；季节尺度干旱发生频率为冬旱>春旱>秋旱>夏旱。从空间变化来看，多年平均降水量由东向西呈逐级递减趋势，降水分布地域特征明显，大兴安岭以东地区和巴彦淖尔市西部地区降水变化趋势率较高，呼伦贝尔市西北部、通辽市中南部、赤峰市中部、阿拉善盟西部地区降水变化趋势率较低；发生不同等级干旱的几率为轻旱>特旱>中旱>重旱，各级干旱易发生地区集中在呼伦贝尔市西部、赤峰市中北部、通辽市北部、锡林郭勒盟中西部以及阿拉善盟西部地区。Pa变化趋势率表现为，呼伦贝尔市中东部、巴彦淖尔市西部和阿拉善盟东部呈上升趋势，即干旱程度减轻；兴安盟南部至鄂尔多斯市、阿拉善盟中西部呈下降趋势，即干旱程度加重。
Subjects: Biology >> Zoology submitted time 2017-11-07 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究松针多糖对正常状态及脂多糖（LPS）刺激状态下小鼠腹腔巨噬细胞的免疫调节作用。试验采用不同浓度的松针多糖作用于正常的和经LPS刺激的小鼠腹腔巨噬细胞，设空白对照组（加入100 µL RPMI-1640培养基）、阳性对照组（加入100 µL终浓度为5 μg/mL的LPS）、松针多糖组（分别加入100 µL 25、50、100、200 µg/mL的松针多糖）和LPS+松针多糖组（加入与松针多糖组相同浓度的松针多糖和终浓度为5 μg/mL的LPS，液体终体积为200 µL）。噻唑蓝（MTT）比色法检测细胞活力，中性红吞噬试验检测巨噬细胞吞噬能力，Griess法检测一氧化氮（NO）的分泌量，酶联免疫吸附测定(ELISA)法检测巨噬细胞培养上清液中白细胞介素-1β（IL-1β）、肿瘤坏死因子-α（TNF-α）、白细胞介素-10（IL-10）的分泌量。结果表明：1）对空白对照组相比，各松针多糖组巨噬细胞相对增殖率均显著或极显著提高（P<0.05或P<0.01），50、100和200 µg/mL松针多糖组巨噬细胞中性红吞噬率显著或极显著提高（P<0.05或P<0.01），各LPS+松针多糖组巨噬细胞中性红吞噬率均极显著提高（P<0.01），200 µg/mL松针多糖组巨噬细胞NO分泌量极显著提高（P<0.01），50、100和200 µg/mL松针多糖组巨噬细胞TNF-α和IL-1β分泌量显著或极显著提高（P<0.05或P<0.01），50、100和200 µg/mL松针多糖组巨噬细胞IL-10分泌量极显著降低（P<0.01）。2）与阳性对照组相比，各松针多糖组巨噬细胞相对增殖率均极显著降低（P<0.01），100和200 µg/mL LPS+松针多糖组巨噬细胞中性红吞噬率极显著升高(P<0.01)，50、100和200 µg/mL LPS+松针多糖组巨噬细胞NO分泌量极显著提高（P<0.01），各LPS+松针多糖组巨噬细胞TNF-α分泌量显著或极显著提高（P<0.05或P<0.01），50、100和200 µg/mL LPS+松针多糖组巨噬细胞IL-1β分泌量显著或极显著提高（P<0.05或P<0.01），100和200 µg/mL LPS+松针多糖组巨噬细胞IL-10分泌量极显著降低（P<0.01）。由此可见，松针多糖通过发挥其促炎作用调节巨噬细胞的免疫功能，进而增强机体抗疾病的能力。
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